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The distinguishing structural feature of single-layered black phosphorus is its puckered structure, which leads to many novel physical properties. In this work, we first present a new parameterization of the Stillinger–Weber potential for single-layered black phosphorus. In doing so, we reveal the importance of a cross-pucker interaction term in capturing its unique mechanical properties, such as a negative Poisson's ratio. In particular, we show that the cross-pucker interaction enables the pucker to act as a re-entrant hinge, which expands in the lateral direction when it is stretched in the longitudinal direction. As a consequence, single-layered black phosphorus has a negative Poisson's ratio in the direction perpendicular to the atomic plane. As an additional demonstration of the impact of the cross-pucker interaction, we show that it is also the key factor that enables capturing the edge stress-induced bending of single-layered black phosphorus that has been reported in ab initio calculations.
Durch Reifungs- und Strukturbildungsprozesse kann es bei silikatischen und alumosilikatischen Bindern zu Rissbildung bei behinderter Verformung, Festigkeitsverlust und somit Verlust der Dauerhaftigkeit kommen. Die Bewertung dieser Prozesse erfolgt an silikatischen Materialien mit einem Ausblick auf die alumosilikatischen Binder.
Durch Reifungs- und Strukturbildungsprozesse kann es bei silikatischen und alumosilikatischen Bindern zu Rissbildung bei behinderter Verformung, Festigkeitsverlust und somit Verlust der Dauerhaftigkeit kommen. Die Bewertung dieser Prozesse erfolgt an silikatischen Materialien mit einem Ausblick auf die alumosilikatischen Binder
Patients and staff in hospitals are exposed to a complex sound environment with rather high noise levels. In intensive care units, the main noise sources are hospital staff on duty and medical equipment, which generates both operating noise and acoustic alarms. Although noise in most cases is produced during activities for the purpose of saving life, noise can induce significant changes in the depth and quality of sleep and negatively affect health in general. Results of a survey of hospital staff are presented as well as measurements in two German hospital wards: a standard two-bed room and a special Intermediate Care Unit (IMC-Unit), each in a different Intensive Care Unit (ICU). Sound pressure data were collected over a 48 hour period and converted into different levels (LAFeq, LAFmax, LAFmin, LAF 5%), as well as a rating level LAr, which is used to take tonality and impulsiveness into account. An analysis of the survey and the measured data, together with a comparison of thresholds of national and international regulations and standards describe the acoustic situation and its likely noise effects on staff and patients.
Im Aufsatz "Zwei Pater noster-Vertonungen von Melchior Vulpius und die Missa V. vocum super Pater noster qui es in Coelis Melchioris Vulpii von Georg Vintz" werden Pater noster-Vertonungen aus dem OPUSCULUM NOVUM SELECTISSIMARVUM CANTIONVM SACRARVM (Erfurt 1610) und aus der PARS PRIMA CANTIONVM SACRARVM (Jena 1602) des Weimarer Kantors und Komponisten Melchior Vulpius (1570 - 1615) besprochen und miteinander verglichen. Ebenso wird untersucht, in welcher Weise der Naumburger Organist Georg Vintz (ca. 1580 - ca. 1635) eine dieser Motetten als Grundlage für die Parodiemesse "MISSA V. VOCUM,Super Pater noster [...] Melchioris Vulpii" genutzt und bearbeitet hat.
Der Aufsatz beruht auf einem Vortrag bei einer Tagung über Vulpius, die 2015 in Meiningen stattfand. Der Tagungsband, den Maren Goltz herausgeben wird, erscheint vermutlich 2018. Da im Band nicht genügend Platz für ausführliche Notenbeispiele ist, werden die besprochenen Kompositionen vollständig als Noten- und Klangdateien durch diesen Permalink zur Verfügung gestellt.
La prima edizione di questo testo è apparsa, in tedesco, nel volume II.2.: Anthologie zum Städtebau. Das Phänomen Großstadt und die Entstehung der Stadt der Moderne, a cura di Vittorio Magnago Lampugnani, Katia Frey, Eliana Perotti, con il sostegno di Departement Architektur der Eidgenössischen Technischen Hochschule, Zürich (Gebr. Mann Verlag, Berlin 2014, pp. 1307-1390). Previ specifici accordi con l’editore, viene qui presentata la versione originaria, in italiano, dell’intero capitolo: Modernität und Emphase. Städtebau im italienischen Faschismus, e comprendente: i) una capiente saggio introduttivo – in una versione più ampia ed articolata (comprensiva della “Bibliografia sistematica”, di riferimento) del testo in tedesco; ii) la versione in italiano del repertorio antologico di riferimento – e comprensiva di una “Scheda introduttiva”, sull’Autore-Opera, e di una selezione del testo in esame.
Spazio sacro e fondazione della comunità. Il tragico òikos dei villaggi di fondazione del fascismo
(2007)
La prima edizione di questo testo è apparsa − in una versione più ridotta −, nel volume: Pasquale Culotta, Giuliano Gresleri, Glauco Gresleri (a cura di), Città di fondazione e “Plantatio Ecclesiae”, Compositori, Bologna 2007, pp. 214-236. Un nutrito pool nazionale, specializzato sulle “Città di fondazione”, in Italia e nelle sue ex-colonie, si è misurato sul tema con una complessa storiografia interdisciplinare, che poneva al centro della sua diagnosi una connotazione teologico-ecumenica – la Plantatio Ecclesiae, appunto – della fenomenologia urbana della fundatio.
Die Bauinformatik ist eine Säule der modernen Bau- und Umweltingenieurwissenschaften und befasst sich mit der Erforschung grundlegender informatorischer Methoden sowie mit der Anwendung und Weiterentwicklung der Informationswissenschaften im Bau- und Umweltbereich. Der Arbeitskreis Bauinformatik konstituiert sich aus Wissenschaftlern, die an Universitäten im deutschsprachigen Raum auf dem Fachgebiet Bauinformatik lehren und forschen. Ausgehend vom erreichten Entwicklungsstand der Bauinformatik skizziert dieses Positionspapier die Aufgaben des Arbeitskreises und formuliert eine Grundlage für eine abgestimmte Weiterentwicklung an den deutschsprachigen Universitäten.
Water substantially affects nearly all physical, chemical and biological processes on the Earth. Recent Mars observations as well as laboratory investigations suggest that water is a key factor of current physical and chemical processes on the Martian surface, e.g. rheological phenomena. Therefore it is of particular interest to get information about the liquid-like state of water on Martian analogue soils for temperatures below 0 °C. To this end, a parallel plate capacitor has been developed to obtain isothermal dielectric spectra of fine-grained soils in the frequency range from 10 Hz to 1.1 MHz at Martian-like temperatures down to −70 °C. Two Martian analogue soils have been investigated: a Ca-bentonite (specific surface of 237 m2 g−1, up to 9.4% w / w gravimetric water content) and JSC Mars 1, a volcanic ash (specific surface of 146 m2 g−1, up to 7.4% w / w). Three soil-specific relaxation processes are observed in the investigated frequency–temperature range: two weak high-frequency processes (bound or hydrated water as well as ice) and a strong low-frequency process due to counter-ion relaxation and the Maxwell–Wagner effect. To characterize the dielectric relaxation behaviour, a generalized fractional dielectric relaxation model was applied assuming three active relaxation processes with relaxation time of the ith process modelled with an Eyring equation. The real part of effective complex soil permittivity at 350 kHz was used to determine ice and liquid-like water content by means of the Birchak or CRIM equation. There are evidence that bentonite down to −70 °C has a liquid-like water content of 1.17 monolayers and JSC Mars 1 a liquid-like water content of 1.96 monolayers.
By allocating real estate investments into the logistics sector, investors highly participate in the economic development of the respective country or city. However, the submarket is very cyclical and special economic influences – such as growing online trade and new logistic networks – affect the performance of the properties. Important parameters on the potential returns are found not only within the real estate market, but also within the global economy and the development of specific industries. This paper aims at examining factors affecting the performance of logistics properties.
Expected dependencies between macroeconomic factors and real estate economic indicators are examined for six major European logistics locations using econometric models, especially correlation and regression. Data series over a period of 25 years were used. The construction of an econometric model was an iterative process integrating both the statistical result and the economic causality.
This text proposes a genealogy of biopolitics based on Michel Foucault’s thought, and on an understanding of it as a philosophico-political notion. In order to elaborate this genealogy, the text takes as its starting point not only politics but also life, as the second component of the term. The hypothesis is the following: To understand what biopolitics means, we have to take seriously Foucault’s assertion of an indetermination of life, as the correlate of power and knowledge. This notion emerges in the epistemic break that takes place around 1800 and that entails the opening up of the notion of biopolitics under the name of governmentality, implying that life is not only the object of biopolitics but also serves as its model.
A coupled thermo-hydro-mechanical model of jointed hard rock for compressed air energy storage
(2014)
Renewable energy resources such as wind and solar are intermittent, which causes instability when being connected to utility grid of electricity. Compressed air energy storage (CAES) provides an economic and technical viable solution to this problem by utilizing subsurface rock cavern to store the electricity generated by renewable energy in the form of compressed air. Though CAES has been used for over three decades, it is only restricted to salt rock or aquifers for air tightness reason. In this paper, the technical feasibility of utilizing hard rock for CAES is investigated by using a coupled thermo-hydro-mechanical (THM) modelling of nonisothermal gas flow. Governing equations are derived from the rules of energy balance, mass balance, and static equilibrium. Cyclic volumetric mass source and heat source models are applied to simulate the gas injection and production. Evaluation is carried out for intact rock and rock with discrete crack, respectively. In both cases, the heat and pressure losses using air mass control and supplementary air injection are compared.
Tensile strain and compress strain can greatly affect the thermal conductivity of graphene nanoribbons (GNRs). However, the effect of GNRs under shear strain, which is also one of the main strain effect, has not been studied systematically yet. In this work, we employ reverse nonequilibrium molecular dynamics (RNEMD) to the systematical study of the thermal conductivity of GNRs (with model size of 4 nm × 15 nm) under the shear strain. Our studies show that the thermal conductivity of GNRs is not sensitive to the shear strain, and the thermal conductivity decreases only 12–16% before the pristine structure is broken. Furthermore, the phonon frequency and the change of the micro-structure of GNRs, such as band angel and bond length, are analyzed to explore the tendency of thermal conductivity. The results show that the main influence of shear strain is on the in-plane phonon density of states (PDOS), whose G band (higher frequency peaks) moved to the low frequency, thus the thermal conductivity is decreased. The unique thermal properties of GNRs under shear strains suggest their great potentials for graphene nanodevices and great potentials in the thermal managements and thermoelectric applications.
The Carbon journal is pleased to introduce a themed collection of recent articles in the area of computational carbon nanoscience. This virtual special issue was assembled from previously published Carbon articles by Guest Editors Quan Wang and Behrouz Arash, and can be accessed as a set in the special issue section of the journal website homepage: www.journals.elsevier.com/carbon. The article below by our guest editors serves as an introduction to this virtual special issue, and also a commentary on the growing role of computation as a tool to understand the synthesis and properties of carbon nanoforms and their behavior in composite materials.
Water content is a key parameter to monitor in nuclear waste repositories such as the planed underground repository in Bure, France, in the Callovo-Oxfordian (COx) clay formation. High-frequency electromagnetic (HF-EM) measurement techniques, i.e., time or frequency domain reflectometry, offer useful tools for quantitative estimation of water content in porous media. However, despite the efficiency of HF-EM methods, the relationship between water content and dielectric material properties needs to be characterized. Moreover, the high amount of swelling clay in the COx clay leads to dielectric relaxation effects which induce strong dispersion coupled with high absorption of EM waves. Against this background, the dielectric relaxation behavior of the clay rock was studied at frequencies from 1 MHz to 10 GHz with network analyzer technique in combination with coaxial transmission line cells. For this purpose, undisturbed and disturbed clay rock samples were conditioned to achieve a water saturation range from 0.16 to nearly saturation. The relaxation behavior was quantified based on a generalized fractional relaxation model under consideration of an apparent direct current conductivity assuming three relaxation processes: a high-frequency water process and two interface processes which are related to interactions between the aqueous pore solution and mineral particles (adsorbed/hydrated water relaxation, counter ion relaxation and Maxwell-Wagner effects). The frequency-dependent HF-EM properties were further modeled based on a novel hydraulic-mechanical-electromagnetic coupling approach developed for soils. The results show the potential of HF-EM techniques for quantitative monitoring of the hydraulic state in underground repositories in clay formations.
This paper presents a novel numerical procedure based on the combination of an edge-based smoothed finite element (ES-FEM) with a phantom-node method for 2D linear elastic fracture mechanics. In the standard phantom-node method, the cracks are formulated by adding phantom nodes, and the cracked element is replaced by two new superimposed elements. This approach is quite simple to implement into existing explicit finite element programs. The shape functions associated with discontinuous elements are similar to those of the standard finite elements, which leads to certain simplification with implementing in the existing codes. The phantom-node method allows modeling discontinuities at an arbitrary location in the mesh. The ES-FEM model owns a close-to-exact stiffness that is much softer than lower-order finite element methods (FEM). Taking advantage of both the ES-FEM and the phantom-node method, we introduce an edge-based strain smoothing technique for the phantom-node method. Numerical results show that the proposed method achieves high accuracy compared with the extended finite element method (XFEM) and other reference solutions.
We apply keyquery-based taxonomy composition to compute a classification system for the CORE dataset, a shared crawl of about 850,000 scientific papers. Keyquery-based taxonomy composition can be understood as a two-phase hierarchical document clustering technique that utilizes search queries as cluster labels: In a first phase, the document collection is indexed by a reference search engine, and the documents are tagged with the search queries they are relevant—for their so-called keyqueries. In a second phase, a hierarchical clustering is formed from the keyqueries within an iterative process. We use the explicit topic model ESA as document retrieval model in order to index the CORE dataset in the reference search engine. Under the ESA retrieval model, documents are represented as vectors of similarities to Wikipedia articles; a methodology proven to be advantageous for text categorization tasks. Our paper presents the generated taxonomy and reports on quantitative properties such as document coverage and processing requirements.
Many researchers are working on developing robots into adequate partners, be it at the working place, be it at home or in leisure activities, or enabling elder persons to lead a self-determined, independent life. While quite some progress has been made in e.g. speech or emotion understanding, processing and expressing, the relations between humans and robots are usually only short-term. In order to build long-term, i.e. social relations, qualities like empathy, trust building, dependability, non-patronizing, and others will be required. But these are just terms and as such no adequate starting points to “program” these capacities even more how to avoid the problems and pitfalls in interactions between humans and robots. However, a rich source for doing this is available, unused until now for this purpose: artistic productions, namely literature, theater plays, not to forget operas, and films with their multitude of examples. Poets, writers, dramatists, screen-writers, etc. have studied for centuries the facets of interactions between persons, their dynamics, and the related snags. And since we wish for human-robot relations as master-servant relations - the human obviously being the master - the study of these relations will be prominent. A procedure is proposed, with four consecutive steps, namely Selection, Analysis, Categorization, and Integration. Only if we succeed in developing robots which are seen as servants we will be successful in supporting and helping humans through robots.
Identity management provides PET (privacy enhancing technology) tools for users to control privacy of their personal data. With the support of mobile location determination techniques based on GPS, WLAN, Bluetooth, etc., context-aware and location-aware mobile applications (e.g. restaurant finder, friend finder, indoor and outdoor navigation, etc.) have gained quite big interest in the business and IT world. Considering sensitive static personal information (e.g. name, address, phone number, etc.) and also dynamic personal information (e.g. current location, velocity in car, current status, etc.), mobile identity management is required to help mobile users to safeguard their personal data. In this paper, we evaluate certain required aspects and features (e.g. context-to-context dependence and relation, blurring in levels, trust management with p3p integration, extended privacy preferences, etc.) of mobile identity management
A simple multiscale analysis framework for heterogeneous solids based on a computational homogenization technique is presented. The macroscopic strain is linked kinematically to the boundary displacement of a circular or spherical representative volume which contains the microscopic information of the material. The macroscopic stress is obtained from the energy principle between the macroscopic scale and the microscopic scale. This new method is applied to several standard examples to show its accuracy and consistency of the method proposed.
VHB-JOURQUAL represents the official journal ranking of the German Academic Association for Business Research. Since its introduction in 2003, the ranking has become the most influential journal evaluation approach in German-speaking countries, impacting several key managerial decisions of German, Austrian, and Swiss business schools. This article reports the methodological approach of the ranking’s second edition. It also presents the main results and additional analyses on the validity of the rating and the underlying decision processes of the respondents. Selected implications for researchers and higher-education institutions are discussed.
Spatial time domain reflectometry (spatial TDR) is a new measurement method for determining water content profiles along elongated probes (transmission lines). The method is based on the inverse modeling of TDR reflectograms using an optimization algorithm. By means of using flat ribbon cables it is possible to take two independent TDRmeasurements from both ends of the probe, which are used to improve the spatial information content of the optimization results and to consider effects caused by electrical conductivity. The method has been used for monitoring water content distributions on a full-scale levee model made of well-graded clean sand. Flood simulation tests, irrigation tests, and long-term observations were carried out on the model. The results show that spatial TDR is able to determine water content distributions with an accuracy of the spatial resolution of about ±3 cm compared to pore pressure measurements and an average deviation of ±2 vol % compared to measurements made using another independent TDR measurement system.
Physicochemical forces are responsible for the swelling pressure development in saturated bentonites. In this paper, the swelling pressures of several compacted bentonite specimens for a range of dry density of 1.10–1.73 Mg/m3 were measured experimentally. The clay used was a divalent-rich Ca-Mg-bentonite with 12% exchangeable Na+ ions. The theoretical swelling pressure–dry density relationship for the bentonite was determined from the Gouy-Chapman diffuse double-layer theory. A comparison of experimental and theoretical results showed that the experimental swelling pressures are either smaller or greater than their theoretical counterparts within different dry density ranges. It is shown that for dry density of the clay less than about 1.55 Mg/m3, a possible dissociation of ions from the surface of the clay platelets contributed to the diffuse double-layer repulsion. At higher dry densities, the adsorptive forces due to surface and ion hydration dominated the swelling pressures of the clay. A comparison of the modified diffuse double-layer theory equations proposed in the literature to determine the swelling pressures of compacted bentonites and the experimental results for the clay in this study showed that the agreement between the calculated and experimental swelling pressure results is very good for dry densities less than 1.55 Mg/m3, whereas at higher dry densities the use of the equations was found to be limited.
The work has studied the structure and properties of gypsum compositions modified with the manmade modifier based on metallurgical dust and multi-walled carbon nanotubes. The results show that changing the structure of solid gypsum leads to the increase in bending and compressive strength by 70,5% and 138% correspondingly, the water resistance increasing and the softening factor reaching 0,85. Modifying gypsum composition with complex additive leads to the formation of amorphous structures based on calcium hydrosilicates on the surface of primary gypsum crystallohydrates that bond gypsum crystals and reduce the access of water.
Media anthropology is a new and interdisciplinary field of research with very different subjects and methods that seems to be already heavily informed by a comparatively narrow understanding of media as mass media (e.g. TV, Internet, social web, etc.). Therefore, most theories in this field, at least implicitly, employ a hierarchical and often dichotomic preconception of the two poles of media-human relations, by analysing the operationalities and ontologies of the human and the media independently from one another. This article deviates from this line of thought by advocating an expanded, symmetrical and relational understanding of the terms media and human, taking them as always already intermingled facets of a broader dynamic configuration. Starting from a consideration of the historically powerful, yet overlooked media of the so-called habitat diorama, the heuristic concept of “anthropomediality” is to be developed. Eventually, this relational approach may open up a new, interesting field for interrogation of (media-)anthropological analysis in general.
The article presents preliminary results and qualitative analysis obtained from the doctoral research provisory entitled “How do Brazilian ‘battlers’ reside?”, which is in progress at the Institute for European Urban Studies, Bauhaus Univer-sity Weimar. It critically discusses the contradictions of the production of residences in Brazil made by an emerging so-cial group, lately called the Brazilian new middle class. For the last ten years, a number of government policies have provoked a general improvement of the purchasing power of the poor. Between those who completely depend on the government to survive and the upper middle class, there is a wide (about 100 million people) and economically stable lower middle group, which has found its own ways of dealing with its demand for housing. The conventional models of planning, building and buying are not suitable for their technical, financial and personal needs. Therefore, they are con-currently planners, constructors and residents, building and renovating their own properties themselves, but still with very limited education and technical knowledge and restricted access to good building materials and constructive ele-ments, formal technicians, architects or engineers. On the one hand, the result is an informal and more or less autono-mous self-production, with all sorts of technical problems and very interesting and creative spatial solutions to every-day domestic situations. On the other hand, the repercussions for urban space are questionable: although basic infrastructure conditions have improved, building densities are high and green areas are few. Lower middle class neigh-bourhoods present a restricted collective everyday life. They look like storage spaces for manpower; people who live to work in order to be able to consume—and build—what they could not before. One question is, to what extent the lat-est economic rise of Brazil has really resulted in social development for lower middle income families in the private sphere regarding their residences, and in the collective sphere, regarding the neighbourhoods they inhabit and the ur-ban space in general.
A known phenomenon during laser welding of thin sheets is the deformation caused by thermally induced stresses. This deformation can result in a change of the gap width between the welded parts, which leads to an unstable welding process. Inducing displacements by using a second heat source will compensate for the change in gap width, hence optimizing the welding process. The base material is 1 mm thick austenitic stainless steel 1.4301, which is welded by a CO2 laser. The second heat source is a diode laser. The gap between the welded parts was set between 0.05 mm and 0.1 mm. The influence of the second heat source on the welding process and the welding result is described. The usage of a second heat source allows a higher gap width to be set prior to the welding process. The results of the numerical simulation were found to be corresponding to those of the experiments.
Strain measurement is important in mechanical testing. A wide variety of techniques exists for measuring strain in the tensile test; namely the strain gauge, extensometer, stress and strain determined by machine crosshead motion, Geometric Moire technique, optical strain measurement techniques and others. Each technique has its own advantages and disadvantages. The purpose of this study is to quantitatively compare the strain measurement techniques. To carry out the tensile test experiments for S 235, sixty samples were cut from the web of the I-profile in longitudinal and transverse directions in four different dimensions. The geometry of samples are analysed by 3D scanner and vernier caliper. In addition, the strain values were determined by using strain gauge, extensometer and machine crosshead motion. Three techniques of strain measurement are compared in quantitative manner based on the calculation of mechanical properties (modulus of elasticity, yield strength, tensile strength, percentage elongation at maximum force) of structural steel. A statistical information was used for evaluating the results. It is seen that the extensometer and strain gauge provided reliable data, however the extensometer offers several advantages over the strain gauge and crosshead motion for testing structural steel in tension. Furthermore, estimation of measurement uncertainty is presented for the basic material parameters extracted through strain measurement.
We conducted extensive molecular dynamics simulations to investigate the thermal conductivity of polycrystalline hexagonal boron-nitride (h-BN) films. To this aim, we constructed large atomistic models of polycrystalline h-BN sheets with random and uniform grain configuration. By performing equilibrium molecular dynamics (EMD) simulations, we investigated the influence of the average grain size on the thermal conductivity of polycrystalline h-BN films at various temperatures. Using the EMD results, we constructed finite element models of polycrystalline h-BN sheets to probe the thermal conductivity of samples with larger grain sizes. Our multiscale investigations not only provide a general viewpoint regarding the heat conduction in h-BN films but also propose that polycrystalline h-BN sheets present high thermal conductivity comparable to monocrystalline sheets.
Stonecutters and Sutong Bridge have pushed the world record for main span length of cable-stayed bridges to over 1000m. The design of these bridges, both located in typhoon prone regions, is strongly influenced by wind effects during their erection. Rigorous wind tunnel test programmes have been devised and executed to determine the aerodynamic behaviour of the structures in the most critical erection conditions. Testing was augmented by analytical and numerical analyses to verify the safety of the structures throughout construction and to ensure that no serviceability problems would affect the erection process. This paper outlines the wind properties assumed for the bridge sites, the experimental test programme with some of its results, the dynamic properties of the bridges during free cantilevering erection and the assessment of their aerodynamic performance. Along the way, it discusses the similarities and some revealing differences between the two bridges in terms of their dynamic response to wind action.
In Zeiten volatiler Immobilienmärkte und einer hohen Wettbewerbsintensität sind leistungsfähige Systeme der Analyse und Entscheidungsunterstützung unverzichtbar. Entscheidungen zu Investitionsstrategien und Einzelinvestitionen basieren zumeist auf mehreren entscheidungsrelevanten Kriterien. Unterschiedliche immobilienwirtschaftliche Entscheidungsalternativen können dabei durchaus Kriterienausprägungen aufweisen, die eine bestimmte Alternative nicht als stets besser bzw. stets schlechter ausweisen. Klassische finanzwirtschaftliche Modelle oder verbreitete qualitative Verfahren wie das Scoring können die gegebene Komplexität meist nicht angemessen berücksichtigen. Eine Weiterentwicklung immobilienwirtschaftlicher Entscheidungsmodelle ist durch die Übertragung und Spezifizierung multikriterieller Verfahren der Entscheidungsunterstützung möglich. Speziell die Untergruppe des Outranking beschäftigt sich mit der schrittweisen Strukturierung, Ordnung und Priorisierung von komplexen Auswahlalternativen. Als spezifische immobilienwirtschaftliche Fragestellung dient hier die Auswahl und Priorisierung von Zielmärkten im taktischen Portfoliomanagement eines institutionellen Immobilienportfoliosmit internationaler Ausrichtung. Die Formalisierung des Entscheidungsproblems „Priorisierung von Zielmärkten“ erfolgt mit dem ELECTRE-Verfahren.
Lack of Information technology applications on construction projects lead to complex flow of data during project life cycle. Building Information Modeling (BIM) has gained attention in the Architectural, Engineering and Construction (AEC) industry, envisage the use of virtual n-dimensional (n-D) models to identify potential conflicts in design, construction or operational of any facility. A questionnaire has been designed to investigate perceptions regarding BIM advantages. Around 102 valid responses received from diversified stakeholders. Results showed very low BIM adoption with low level of ‘Buzz’. BIM is a faster and more effective method for designing and construction management, it improves quality of the design and construction and reduces rework during construction; which came out as the top thee advantages according to the perception of AEC professionals of Pakistan.BIM has least impact on reduction of cost, time and human resources. This research is a bench mark study to understand adoption and advantageous of BIM in Pakistan Construction Industry.
Water substantially affects nearly all physical, chemical and biological processes on the Earth. Recent Mars observations as well as laboratory investigations suggest that water is a key factor of current physical and chemical processes on the Martian surface, e.g. rheological phenomena. Therefore it is of particular interest to get information about the liquid-like state of water on Martian analogue soils for temperatures below 0 °C. To this end, a parallel plate capacitor has been developed to obtain isothermal dielectric spectra of fine-grained soils in the frequency range from 10 Hz to 1.1 MHz at Martian-like temperatures down to −70 °C. Two Martian analogue soils have been investigated: a Ca-bentonite (specific surface of 237 m2 g−1, up to 9.4% w / w gravimetric water content) and JSC Mars 1, a volcanic ash (specific surface of 146 m2 g−1, up to 7.4% w / w). Three soil-specific relaxation processes are observed in the investigated frequency–temperature range: two weak high-frequency processes (bound or hydrated water as well as ice) and a strong low-frequency process due to counter-ion relaxation and the Maxwell–Wagner effect. To characterize the dielectric relaxation behaviour, a generalized fractional dielectric relaxation model was applied assuming three active relaxation processes with relaxation time of the ith process modelled with an Eyring equation. The real part of effective complex soil permittivity at 350 kHz was used to determine ice and liquid-like water content by means of the Birchak or CRIM equation. There are evidence that bentonite down to −70 °C has a liquid-like water content of 1.17 monolayers and JSC Mars 1 a liquid-like water content of 1.96 monolayers.
The mechanism and the kinetics of hydration reactions are important for the application of a salt hydrate as a thermochemical heat storage material. MgSO4·H2O and Na2SO4 were chosen in this study because they are both promising candidates for such an application. Considering that the hydration of these salts yields MgSO4·7H2O and Na2SO4·10H2O as the reaction products, the maximum overall heat effect can be calculated from the heat of condensation of water vapor (44 kJ mol–1) and the heats of hydration of 75 kJ·mol-1 (for MgSO4·H2O) and 81 kJ mol-1 (for Na2SO4). Based on the densities of the two hydrated phases, this results in the very high theoretical energy densities of 2.3 GJ·m-3 and 2.4 GJ·m-3, respectively, for MgSO4·7H2O and Na2SO4·10H2O. Not only the energy density is important for the dimensioning of a storage system, but also the kinetics of hydration reactions play a major role for the application as storage material. In the present study, hydration reactions under varying climatic conditions were investigated by using water vapor sorption measurements and in-situ Raman microscopy. Using the phase diagrams, it can be clearly shown that the mechanism and the kinetics depend on the climatic conditions. Below the deliquescence humidity of the lower hydrated phase the hydration proceeds as solid state reaction, whilst above the deliquescence humidity a through solution mechanism takes place.
Rice husk ash (RHA) is classified as a highly reactive pozzolan. It has a very high silica content similar to that of silica fume (SF). Using less-expensive and locally available RHA as a mineral admixture in concrete brings ample benefits to the costs, the technical properties of concrete as well as to the environment. An experimental study of the effect of RHA blending on workability, strength and durability of high performance fine-grained concrete (HPFGC) is presented. The results show that the addition of RHA to HPFGC improved significantly compressive strength, splitting tensile strength and chloride penetration resistance. Interestingly, the ratio of compressive strength to splitting tensile strength of HPFGC was lower than that of ordinary concrete, especially for the concrete made with 20 % RHA. Compressive strength and splitting tensile strength of HPFGC containing RHA was similar and slightly higher, respectively, than for HPFGC containing SF. Chloride penetration resistance of HPFGC containing 10–15 % RHA was comparable with that of HPFGC containing 10 % SF.
Flow velocity is generally presumed to influence flood damage. However, this influence is hardly quantified and virtually no damage models take it into account. Therefore, the influences of flow velocity, water depth and combinations of these two impact parameters on various types of flood damage were investigated in five communities affected by the Elbe catchment flood in Germany in 2002. 2-D hydraulic models with high to medium spatial resolutions were used to calculate the impact parameters at the sites in which damage occurred. A significant influence of flow velocity on structural damage, particularly on roads, could be shown in contrast to a minor influence on monetary losses and business interruption. Forecasts of structural damage to road infrastructure should be based on flow velocity alone. The energy head is suggested as a suitable flood impact parameter for reliable forecasting of structural damage to residential buildings above a critical impact level of 2m of energy head or water depth. However, general consideration of flow velocity in flood damage modelling, particularly for estimating monetary loss, cannot be recommended.
We present StarWatch, our application for real-time analysis of radio astronomical data in Virtual Environment. Serving as an interface to radio astronomical databases or being applied to live data from the radio telescopes, the application supports various data filters measuring signal-to-noise ratio (SNR), Doppler's drift, degree of signal localization on celestial sphere and other useful tools for signal extraction and classification. Originally designed for the database of narrow band signals from SETI Institute (setilive.org), the application has been recently extended for the detection of wide band periodic signals, necessary for the search of pulsars. We will also address the detection of week signals possessing arbitrary waveforms and present several data filters suitable for this purpose.
Traditionally, buildings in the Inner Himalayan valleys of Bhutan were constructed from rammed earth in the western regions and quarry stone in the central and eastern regions. Whilst basic architectural design elements have been retained, the construction methods have however changed over recent decades alongside expectations for indoor thermal comfort. Nevertheless, despite the need for space heating, thermal building performance remains largely unknown. Furthermore, no dedicated climate data is available for building performance assessments. This paper establishes such climatological information for the capital Thimphu and presents an investigation of building physics properties of traditional and contemporary building types. In a one month field study 10 buildings were surveyed, looking at building air tightness, indoor climate, wall U-values and water absorption of typical wall construction materials. The findings highlight comparably high wall U-values of 1.0 to 1.5 W/m²K for both current and historic constructions. Furthermore, air tightness tests show that, due to poorly sealed joints between construction elements, windows and doors, many buildings have high infiltration rates, reaching up to 5 air changes per hour. However, the results also indicate an indoor climate moderating effect of more traditional earth construction techniques. Based on these survey findings basic improvements are being suggested.
We investigate the thermal conductivity in the armchair and zigzag MoS2 nanoribbons, by combining the non-equilibrium Green's function approach and the first-principles method. A strong orientation dependence is observed in the thermal conductivity. Particularly, the thermal conductivity for the armchair MoS2 nanoribbon is about 673.6 Wm−1 K−1 in the armchair nanoribbon, and 841.1 Wm−1 K−1 in the zigzag nanoribbon at room temperature. By calculating the Caroli transmission, we disclose the underlying mechanism for this strong orientation dependence to be the fewer phonon transport channels in the armchair MoS2 nanoribbon in the frequency range of [150, 200] cm−1. Through the scaling of the phonon dispersion, we further illustrate that the thermal conductivity calculated for the MoS2 nanoribbon is esentially in consistent with the superior thermal conductivity found for graphene.
In this study, an application of evolutionary multi-objective optimization algorithms on the optimization of sandwich structures is presented. The solution strategy is known as Elitist Non-Dominated Sorting Evolution Strategy (ENSES) wherein Evolution Strategies (ES) as Evolutionary Algorithm (EA) in the elitist Non-dominated Sorting Genetic algorithm (NSGA-II) procedure. Evolutionary algorithm seems a compatible approach to resolve multi-objective optimization problems because it is inspired by natural evolution, which closely linked to Artificial Intelligence (AI) techniques and elitism has shown an important factor for improving evolutionary multi-objective search. In order to evaluate the notion of performance by ENSES, the well-known study case of sandwich structures are reconsidered. For Case 1, the goals of the multi-objective optimization are minimization of the deflection and the weight of the sandwich structures. The length, the core and skin thicknesses are the design variables of Case 1. For Case 2, the objective functions are the fabrication cost, the beam weight and the end deflection of the sandwich structures. There are four design variables i.e., the weld height, the weld length, the beam depth and the beam width in Case 2. Numerical results are presented in terms of Paretooptimal solutions for both evaluated cases.
Processes underlying crowding in visual letter recognition were examined by investigating effects of training. Experiment 1 revealed that training reduces crowding mainly for trained strings. This was corroborated in Experiment 2, where no training effects were obvious after 3 days of training when strings changed from trial to trial. Experiment 3 specified that after a short amount of training, learning effects remained specific to trained strings and also to the trained retinal eccentricity and the interletter spacing used in training. Transfer to other than trained conditions was observed only after further training. Experiment 4 showed that transfer occurred earlier when words were used as stimuli. These results thus demonstrate that part of crowding results from the absence of higher level representations of the stimulus. Such representations can be acquired through learning visual properties of the stimulus.
The laser beam is a small, flexible and fast polishing tool. With laser radiation it is possible to finish many outlines or geometries on quartz glass surfaces in the shortest possible time. It’s a fact that the temperature developing while polishing determines the reachable surface smoothing and, as a negative result, causes material tensions. To find out which parameters are important for the laser polishing process and the surface roughness respectively and to estimate material tensions, temperature simulations and extensive polishing experiments took place. During these experiments starting and machining parameters were changed and temperatures were measured contact-free. The accuracy of thermal and mechanical simulation was improved in the case of advanced FE-analysis.
The laser beam is a small, flexible and fast polishing tool. With laser radiation it is possible to finish many outlines or geometries on quartz glass surfaces in the shortest possible time. It's a fact that the temperature developing while polishing determines the reachable surface smoothing and, as a negative result, causes material tensions. To find out which parameters are important for the laser polishing process and the surface roughness respectively and to estimate material tensions, temperature simulations and extensive polishing experiments took place. During these experiments starting and machining parameters were changed and temperatures were measured contact-free.
Cyber security has become a major concern for users and businesses alike. Cyberstalking and harassment have been identified as a growing anti-social problem. Besides detecting cyberstalking and harassment, there is the need to gather digital evidence, often by the victim. To this end, we provide an overview of and discuss relevant technological means, in particular coming from text analytics as well as machine learning, that are capable to address the above challenges. We present a framework for the detection of text-based cyberstalking and the role and challenges of some core techniques such as author identification, text classification and personalisation. We then discuss PAN, a network and evaluation initiative that focusses on digital text forensics, in particular author identification.
Urban and building energy simulation models are usually driven by typical meteorological year (TMY) weather data often in a TMY2 or EPW format. However, the locations where these historical datasets were collected (usually airports) generally do not represent the local, site specific micro-climates that cities develop. In this paper, a humid sub-tropical climate context has been considered. An idealised “urban unit model” of 250 m radius is being presented as a method of adapting commonly available weather data files to the local micro-climate. This idealised “urban unit model” is based on the main thermal and morphological characteristics of nine sites with residential/institutional (university) use in Hangzhou, China. The area of the urban unit was determined by the region of influence on the air temperature signal at the centre of the unit. Air temperature and relative humidity were monitored and the characteristics of the surroundings assessed (eg green-space, blue-space, built form). The “urban unit model” was then implemented into micro-climatic simulations using a Computational Fluid Dynamics – Surface Energy Balance analysis tool (ENVI-met, Version 4). The “urban unit model” approach used here in the simulations delivered results with performance evaluation indices comparable to previously published work (for air temperature; RMSE <1, index of agreement d > 0.9). The micro-climatic simulation results were then used to adapt the air temperature and relative humidity of the TMY file for Hangzhou to represent the local, site specific morphology under three different weather forcing cases, (ie cloudy/rainy weather (Group 1), clear sky, average weather conditions (Group 2) and clear sky, hot weather (Group 3)). Following model validation, two scenarios (domestic and non-domestic building use) were developed to assess building heating and cooling loads against the business as usual case of using typical meteorological year data files. The final “urban weather projections” obtained from the simulations with the “urban unit model” were used to compare the degree days amongst the reference TMY file, the TMY file with a bulk UHI offset and the TMY file adapted for the site-specific micro-climate (TMY-UWP). The comparison shows that Heating Degree Days (HDD) of the TMY file (1598 days) decreased by 6 % in the “TMY + UHI” case and 13 % in the “TMY-UWP” case showing that the local specific micro-climate is attributed with an additional 7 % (ie from 6 to 13 %) reduction in relation to the bulk UHI effect in the city. The Cooling Degree Days (CDD) from the “TMY + UHI” file are 17 % more than the reference TMY (207 days) and the use of the “TMY-UWP” file results to an additional 14 % increase in comparison with the “TMY + UHI” file (ie from 17 to 31 %). This difference between the TMY-UWP and the TMY + UHI files is a reflection of the thermal characteristics of the specific urban morphology of the studied sites compared to the wider city. A dynamic thermal simulation tool (TRNSYS) was used to calculate the heating and cooling load demand change in a domestic and a non-domestic building scenario. The heating and cooling loads calculated with the adapted TMY-UWP file show that in both scenarios there is an increase by approximately 20 % of the cooling load and a 20 % decrease of the heating load. If typical COP values for a reversible air-conditioning system are 2.0 for heating and 3.5 for cooling then the total electricity consumption estimated with the use of the “urbanised” TMY-UWP file will be decreased by 11 % in comparison with the “business as usual” (ie reference TMY) case. Overall, it was found that the proposed method is appropriate for urban and building energy performance simulations in humid sub-tropical climate cities such as Hangzhou, addressing some of the shortfalls of current simulation weather data sets such as the TMY.
In vielen öffentlichen Gebäuden besteht ein hohes wirtschaftliches Einsparpotenzial bei den relevanten Energieträgern Wärme und Strom. Projekte zur energetischen Optimierungen refinanzieren sich häufig nach wenigen Jahren. Die notwenigen Investitionsmittel stehen jedoch nur begrenzt zur Verfügung. Zielgerichtete Analysen und Potenzialschätzungen sind erforderlich, um eine Priorisierung optionaler Maßnahmen zu erreichen. Die Studie zeigt anhand eines öffentlichen Portfolios notwendige Untersuchungsschritte auf. Die Einzelpotenziale werden über geeignete Benchmarks ermittelt. Auf Portfolioebene werden u. a. spezifische Potenzial-Matrizen genutzt. Die kennzahlenbasierte Priorisierung von Maßnahmen ist umso wichtiger, je stärker das Potenzial auf wenige Objekte konzentriert ist.
This paper examines the interactions between issues such as ideology, neoliberalism, institution-building and sustainable development. The central focus of the paper is to demonstrate that the neoliberalism hasn’t succeeded just because it is an economic strategy which better serves the interests of the capitalist class (though it must be stressed that this fact has obviously contributed) but mainly because it has been promoted as an attractive economic strategy by respected, well organized and transnationalized institutions all around the globe, and understand the reasons behind this institutional support. After reviewing the interrelationships between the Bretton-Woods institutions and their relationship with the concepts of neoliberalism and sustainable development, the paper concludes claiming that the so-called neoliberal ideology operates behind the discourses of growth, progress and sustainability and that it is in charge of softening domination by diffusing legitimating ideas and granting concessions to subordinate forces, thus implying significations and values that transcend the possible manipulation of the world as an object.
Broadband electromagnetic frequency or time domain sensor techniques present high potential for quantitative water content monitoring in porous media. Prior to in situ application, the impact of the relationship between the broadband electromagnetic properties of the porous material (clay-rock) and the water content on the frequency or time domain sensor response is required. For this purpose, dielectric properties of intact clay rock samples experimental determined in the frequency range from 1 MHz to 10 GHz were used as input data in 3-D numerical frequency domain finite element field calculations to model the one port broadband frequency or time domain transfer function for a three rods based sensor embedded in the clay-rock. The sensor response in terms of the reflection factor was analyzed in time domain with classical travel time analysis in combination with an empirical model according to Topp equation, as well as the theoretical Lichtenecker and Rother model (LRM) to estimate the volumetric water content. The mixture equation considering the appropriate porosity of the investigated material provide a practical and efficient approach for water content estimation based on classical travel time analysis with the onset-method. The inflection method is not recommended for water content estimation in electrical dispersive and absorptive material. Moreover, the results clearly indicate that effects due to coupling of the sensor to the material cannot be neglected. Coupling problems caused by an air gap lead to dramatic effects on water content estimation, even for submillimeter gaps. Thus, the quantitative determination of the in situ water content requires careful sensor installation in order to reach a perfect probe clay rock coupling.
Building Information Modeling is a powerful tool for the design and for a consistent set of data in a virtual storage. For the application in the phases of realization and on site it needs further development. The paper describes main challenges and main features, which will help the development of software to better service the needs of construction site managers
The point collocation method of finite spheres (PCMFS) is used to model the hyperelastic response of soft biological tissue in real time within the framework of virtual surgery simulation. The proper orthogonal decomposition (POD) model order reduction (MOR) technique was used to achieve reduced-order model of the problem, minimizing computational cost. The PCMFS is a physics-based meshfree numerical technique for real-time simulation of surgical procedures where the approximation functions are applied directly on the strong form of the boundary value problem without the need for integration, increasing computational efficiency. Since computational speed has a significant role in simulation of surgical procedures, the proposed technique was able to model realistic nonlinear behavior of organs in real time. Numerical results are shown to demonstrate the effectiveness of the new methodology through a comparison between full and reduced analyses for several nonlinear problems. It is shown that the proposed technique was able to achieve good agreement with the full model; moreover, the computational and data storage costs were significantly reduced.
This study is focused on finite element analysis of a model comprising femur into which a femoral component of a total hip replacement was implanted. The considered prosthesis is fabricated from a functionally graded material (FGM) comprising a layer of a titanium alloy bonded to a layer of hydroxyapatite. The elastic modulus of the FGM was adjusted in the radial, longitudinal, and longitudinal-radial directions by altering the volume fraction gradient exponent. Four cases were studied, involving two different methods of anchoring the prosthesis to the spongy bone and two cases of applied loading. The results revealed that the FG prostheses provoked more SED to the bone. The FG prostheses carried less stress, while more stress was induced to the bone and cement. Meanwhile, less shear interface stress was stimulated to the prosthesis-bone interface in the noncemented FG prostheses. The cement-bone interface carried more stress compared to the prosthesis-cement interface. Stair climbing induced more harmful effects to the implanted femur components compared to the normal walking by causing more stress. Therefore, stress shielding, developed stresses, and interface stresses in the THR components could be adjusted through the controlling stiffness of the FG prosthesis by managing volume fraction gradient exponent.
The node moving and multistage node enrichment adaptive refinement procedures are extended in mixed discrete least squares meshless (MDLSM) method for efficient analysis of elasticity problems. In the formulation of MDLSM method, mixed formulation is accepted to avoid second-order differentiation of shape functions and to obtain displacements and stresses simultaneously. In the refinement procedures, a robust error estimator based on the value of the least square residuals functional of the governing differential equations and its boundaries at nodal points is used which is inherently available from the MDLSM formulation and can efficiently identify the zones with higher numerical errors. The results are compared with the refinement procedures in the irreducible formulation of discrete least squares meshless (DLSM) method and show the accuracy and efficiency of the proposed procedures. Also, the comparison of the error norms and convergence rate show the fidelity of the proposed adaptive refinement procedures in the MDLSM method.
Different types of data provide different type of information. The present research analyzes the error on prediction obtained under different data type availability for calibration. The contribution of different measurement types to model calibration and prognosis are evaluated. A coupled 2D hydro-mechanical model of a water retaining dam is taken as an example. Here, the mean effective stress in the porous skeleton is reduced due to an increase in pore water pressure under drawdown conditions. Relevant model parameters are identified by scaled sensitivities. Then, Particle Swarm Optimization is applied to determine the optimal parameter values and finally, the error in prognosis is determined. We compare the predictions of the optimized models with results from a forward run of the reference model to obtain the actual prediction errors. The analyses presented here were performed calibrating the hydro-mechanical model to 31 data sets of 100 observations of varying data types. The prognosis results improve when using diversified information for calibration. However, when using several types of information, the number of observations has to be increased to be able to cover a representative part of the model domain. For an analysis with constant number of observations, a compromise between data type availability and domain coverage proves to be the best solution. Which type of calibration information contributes to the best prognoses could not be determined in advance. The error in model prognosis does not depend on the error in calibration, but on the parameter error, which unfortunately cannot be determined in inverse problems since we do not know its real value. The best prognoses were obtained independent of calibration fit. However, excellent calibration fits led to an increase in prognosis error variation. In the case of excellent fits; parameters' values came near the limits of reasonable physical values more often. To improve the prognoses reliability, the expected value of the parameters should be considered as prior information on the optimization algorithm.
We demonstrate how logical operations can be implemented in ensembles of protoplasmic tubes of acellular slime mold Physarum polycephalum. The tactile response of the protoplasmic tubes is used to actuate analogs of two- and four-input logical gates and memory devices. The slime mold tube logical gates display results of logical operations by blocking flow in mechanically stimulated tube fragments and redirecting the flow to output tube fragments. We demonstrate how XOR and NOR gates are constructed. We also exemplify circuits of hybrid gates and a memory device. The slime mold based gates are non-electronic, simple and inexpensive, and several gates can be realized simultaneously at sites where protoplasmic tubes merge.
Looking at our face in a mirror is one of the strongest phenomenological experiences of the Self in which we need to identify the face as reflected in the mirror as belonging to us. Recent behavioral and neuroimaging studies reported that self-face identification not only relies upon visual-mnemonic representation of ones own face but also upon continuous updating and integration of visuo-tactile signals. Therefore, bodily self-consciousness plays a major role in self-face identification, with respect to interplay between unisensory and multisensory processing. However, if previous studies demonstrated that the integration of multisensory body-related signals contributes to the visual processing of ones own face, there is so far no data regarding how self-face identification, inversely, contributes to bodily self-consciousness. In the present study, we tested whether selfother face identification impacts either the egocentered or heterocentered visuo-spatial mechanisms that are core processes of bodily self-consciousness and sustain selfother distinction. For that, we developed a new paradigm, named Double Mirror. This paradigm, consisting of a semi-transparent double mirror and computer-controlled Light Emitting Diodes, elicits selfother face merging illusory effect in ecologically more valid conditions, i.e., when participants are physically facing each other and interacting. Self-face identification was manipulated by exposing pairs of participants to an Interpersonal Visual Stimulation in which the reflection of their faces merged in the mirror. Participants simultaneously performed visuo-spatial and mental own-body transformation tasks centered on their own face (egocentered) or the face of their partner (heterocentered) in the pre- and post-stimulation phase. We show that selfother face identification altered the egocentered visuo-spatial mechanisms. Heterocentered coding was preserved. Our data suggest that changes in self-face identification induced a bottom-up conflict between the current visual representation and the stored mnemonic representation of ones own face which, in turn, top-down impacted bodily self-consciousness.
Paraffin Nanocomposites for Heat Management of Lithium-Ion Batteries: A Computational Investigation
(2016)
Lithium-ion (Li-ion) batteries are currently considered as vital components for advances in mobile technologies such as those in communications and transport. Nonetheless, Li-ion batteries suffer from temperature rises which sometimes lead to operational damages or may even cause fire. An appropriate solution to control the temperature changes during the operation of Li-ion batteries is to embed batteries inside a paraffin matrix to absorb and dissipate heat. In the present work, we aimed to investigate the possibility of making paraffin nanocomposites for better heat management of a Li-ion battery pack. To fulfill this aim, heat generation during a battery charging/discharging cycles was simulated using Newman’s well established electrochemical pseudo-2D model. We couple this model to a 3D heat transfer model to predict the temperature evolution during the battery operation. In the later model, we considered different paraffin nanocomposites structures made by the addition of graphene, carbon nanotubes, and fullerene by assuming the same thermal conductivity for all fillers. This way, our results mainly correlate with the geometry of the fillers. Our results assess the degree of enhancement in heat dissipation of Li-ion batteries through the use of paraffin nanocomposites. Our results may be used as a guide for experimental set-ups to improve the heat management of Li-ion batteries.
Previous publications about biochar in anaerobic digestion show encouraging results with regard to increased biogas yields. This work investigates such effects in a solid-state fermentation of bio-waste. Unlike in previous trials, the influence of biochar is tested with a setup that simulates an industrial-scale biogas plant. Both the biogas and the methane yield increased around 5% with a biochar addition of 5%-based on organic dry matter biochar to bio-waste. An addition of 10% increased the yield by around 3%. While scaling effects prohibit a simple transfer of the results to industrial-scale plants, and although the certainty of the results is reduced by the heterogeneity of the bio-waste, further research in this direction seems promising.
Purpose of this study is to evaluate safety impact of the deceleration lane at the Upstream Zone of at-grade U-turns on 4-lane divided Thai highways. A substantial speed reduction is required by vehicles for diverging and making U-turn, and the deceleration lanes are provided for this purpose. These lanes are also providing a storage space for the U-turning vehicles to avoid unnecessary blockage of through lanes and reduce the potential of rear-end collisions. The safety at the U-turn is greatly influenced by the proper or improper use of the deceleration lanes. Subject to their length, full or partial speed adjustment can occur within the deceleration lane also the road users’ behavior is influenced. To assess the safety impact, the four groups of U-turns with the varying length of deceleration lanes were identified. Owing to limitation of availability and reliability of road crash data in Thailand, widely accepted Traffic Conflict Technique (TCT) was used as an alternative and proactive methodology. The U-turns’ geometric data, traffic conflicts and volume data were recorded in the field at 8 locations, 8 hours per location. Severity Conflict Rate (SCR) was assessed by applying a weighing factor (based on the severity grades according to the Czech TCT) to the observed conflicts related to the conflicting traffic volumes. A comparative higher value of SCR represents a lower level of safety. According to the results, increase in the functional length of the deceleration lane yields a lower value of SCR and a higher level of the road safety.
To assess the safety impact of auxiliary lanes at downstream locations of U-turns, the Traffic Conflict Technique was used. On the basis of the installed components at those locations, four types of U-turns were identified: those without any auxiliary lane, those with an acceleration lane, those with outer widening, and those with both an acceleration lane and outer widening. The available crash data is unreliable, therefore to assess the level of road safety, Conflict Indexes were formulated to put more emphasis on severe crashes than on slight ones by using two types of weighting coefficients. The first coefficient was based on the subjective assessment of the seriousness of the conflict situation and the second was based on the relative speed and angle between conflicting streams. A comparatively higher Conflict Index value represents a lower level of road safety. According to the results, a lower level of road safety occurs if two components apply or if a location is without any auxiliary lane. The highest level of road safety occurs if the layout includes only a single component, either an acceleration lane or outer widening.
Assessing Essential Qualities of Urban Space with Emotional and Visual Data Based on GIS Technique
(2016)
Finding a method to evaluate people’s emotional responses to urban spaces in a valid and objective way is fundamentally important for urban design practices and related policy making. Analysis of the essential qualities of urban space could be made both more effective and more accurate using innovative information techniques that have become available in the era of big data. This study introduces an integrated method based on geographical information systems (GIS) and an emotion-tracking technique to quantify the relationship between people’s emotional responses and urban space. This method can evaluate the degree to which people’s emotional responses are influenced by multiple urban characteristics such as building shapes and textures, isovist parameters, visual entropy, and visual fractals. The results indicate that urban spaces may influence people’s emotional responses through both spatial sequence arrangements and shifting scenario sequences. Emotional data were collected with body sensors and GPS devices. Spatial clustering was detected to target effective sampling locations; then, isovists were generated to extract building textures. Logistic regression and a receiver operating characteristic analysis were used to determine the key isovist parameters and the probabilities that they influenced people’s emotion. Finally, based on the results, we make some suggestions for design professionals in the field of urban space optimization.
The current study attempts to recognise an adequate classification for a semi-rigid beam-to-column connection by investigating strength, stiffness and ductility. For this purpose, an experimental test was carried out to investigate the moment-rotation (M-theta) features of flush end-plate (FEP) connections including variable parameters like size and number of bolts, thickness of end-plate, and finally, size of beams and columns. The initial elastic stiffness and ultimate moment capacity of connections were determined by an extensive analytical procedure from the proposed method prescribed by ANSI/AISC 360-10, and Eurocode 3 Part 1-8 specifications. The behaviour of beams with partially restrained or semi-rigid connections were also studied by incorporating classical analysis methods. The results confirmed that thickness of the column flange and end-plate substantially govern over the initial rotational stiffness of of flush end-plate connections. The results also clearly showed that EC3 provided a more reliable classification index for flush end-plate (FEP) connections. The findings from this study make significant contributions to the current literature as the actual response characteristics of such connections are non-linear. Therefore, such semirigid behaviour should be used to for an analysis and design method.
Egypt is a nation of 4000 years of civilization, which was known for its ancient architecture that occupied the highest rank of importance, but how long will our neglected heritage sites survive in our recent era? This is a rising debate. This paper is based on a hypothesis whether the conservation of the neglected or isolated heritage sites, particularly in the inhabited areas, can bind the citizens to their past. For this reason, the research provides scenes of many applied conservation practices in other countries. The study calls for developing a new applied approach of conservation that takes the interaction between citizens and the city heritage zones into consideration.
The paper gives the results of scientific research, which, being based on probabilistic and statistical modeling, identifies the relationship of certain socio-economic factors and the number of people killed in road accidents in the Russian Federation regions. It notes the identity of processes in various fields, in which there is loss of life. Scientific methods and techniques were used in the process of data processing and study findings: systematic approach, methods of system analysis (algorithmization, mathematical programming) and mathematical statistics. The scientific novelty lies in the formulation, formalization and solving problems related to the analysis of regional road traffic accidents, its modeling taking into account the factors of socio-economic impact.
The fire resistance of concrete members is controlled by the temperature distribution of the considered cross section. The thermal analysis can be performed with the advanced temperature dependent physical properties provided by 5EN6 1992-1-2. But the recalculation of laboratory tests on columns from 5TU6 Braunschweig shows, that there are deviations between the calculated and measured temperatures. Therefore it can be assumed, that the mathematical formulation of these thermal properties could be improved. A sensitivity analysis is performed to identify the governing parameters of the temperature calculation and a nonlinear optimization method is used to enhance the formulation of the thermal properties. The proposed simplified properties are partly validated by the recalculation of measured temperatures of concrete columns. These first results show, that the scatter of the differences from the calculated to the measured temperatures can be reduced by the proposed simple model for the thermal analysis of concrete.
In this work different fibre optic sensors for the structural health monitoring of civil engineering structures are reported. A fibre optic crack sensor and two different fibre optic moisture sensors have been designed to detect the moisture ingress in concrete based building structures. Moreover, the degeneration of the mechanical properties of optical glass fibre sensors and hence their long-term stability and reliability due to the mechanical and chemical impact of the concrete environment is discussed as well as the advantage of applying a fibre optic sensor system for the structural health monitoring of sewerage tunnels is demonstrated.
Development of sustainable urban environments assumes processing of large amount of data from various sources. It could be field study observations, results of simulations or information provided by modeling. This paper focuses on processing modeled data of pedestrian movement based on existed axial maps of particular environment. Introduced component allows further analysis by calculation of set of metrics based on inverted graph, which is built from given paths.
Die thermodynamischen Grundlagen der Hydratation von Hüttensand als Hauptbestandteil von Zementen werden erforscht. Hierbei werden thermodynamische Bildungs- und Reaktionsdaten experimentell bestimmt und berechnet. Darüber hinaus wird der Prozess der Feststoffauflösung von Hüttensand in wässrigen Lösungen untersucht. Lösungs- und Fällungsprozesse werden unter verschiedenen Konditionen gemessen, ausgewertet und diskutiert. Die Ergebnisse werden im weiteren Verlauf zur Bestimmung der Hydratationsgrades in Pasten sowie zum besseren Verständnis in der Wechselwirkung zwischen Hüttensanden und Mahlhilfsstoffen genutzt und angewandt.
Augmented Urban Model: Ein Tangible User Interface zur Unterstützung von Stadtplanungsprozessen
(2011)
Im architektonischen und städtebaulichen Kontext erfüllen physische und digitale Modelle aufgrund ihrer weitgehend komplementären Eigenschaften und Qualitäten unterschiedliche, nicht verknüpfte Aufgaben und Funktionen im Entwurfs- und Planungsprozess. Während physische Modelle vor allem als Darstellungs- und Kommunikationsmittel aber auch als Arbeitswerkzeug genutzt werden, unterstützen digitale Modelle darüber hinaus die Evaluation eines Entwurfs durch computergestützte Analyse- und Simulationstechniken.
Analysiert wurden im Rahmen der in diesem Arbeitspapier vorgestellten Arbeit neben dem Einsatz des Modells als analogem und digitalem Werkzeug im Entwurf die Bedeutung des Modells für den Arbeitsprozess sowie Vorbilder aus dem Bereich der Tangible User Interfaces mit Bezug zu Architek¬tur und Städtebau. Aus diesen Betrachtungen heraus wurde ein Prototyp entwickelt, das Augmented Urban Model, das unter anderem auf den frühen Projekten und Forschungsansätzen aus dem Gebiet der Tangible User Interfaces aufsetzt, wie dem metaDESK von Ullmer und Ishii und dem Urban Planning Tool Urp von Underkoffler und Ishii.
Das Augmented Urban Model zielt darauf ab, die im aktuellen Entwurfs- und Planungsprozess fehlende Brücke zwischen realen und digitalen Modellwelten zu schlagen und gleichzeitig eine neue tangible Benutzerschnittstelle zu schaffen, welche die Manipulation von und die Interaktion mit digitalen Daten im realen Raum ermöglicht.
Dieses Arbeitspapier beschreibt, wie ausgehend von einem vorhandenen Straßennetzwerk Bebauungsareale mithilfe von Unterteilungsalgorithmen automatisch umgelegt, d.h. in Grundstücke unterteilt, und anschließend auf Basis verschiedener städtebaulicher Typen bebaut werden können. Die Unterteilung von Bebauungsarealen und die Generierung von Bebauungsstrukturen unterliegen dabei bestimmten stadtplanerischen Einschränkungen, Vorgaben und Parametern. Ziel ist es aus den dargestellten Untersuchungen heraus ein Vorschlagssystem für stadtplanerische Entwürfe zu entwickeln, das anhand der Umsetzung eines ersten Softwareprototyps zur Generierung von Stadtstrukturen weiter diskutiert wird.
Aktionsräume in Dresden
(2012)
In vorliegender Studie werden die Aktionsräume von Befragten in Dresden über eine standardisierte Befragung (n=360) untersucht. Die den Aktionsräumen zugrundeliegenden Aktivitäten werden unterschieden in Einkaufen für den täglichen Bedarf, Ausgehen (z.B. in Café, Kneipe, Gaststätte), Erholung im Freien (z.B. spazieren gehen, Nutzung von Grünanlagen) und private Geselligkeit (z.B. Feiern, Besuch von Verwandten/Freunden). Der Aktionsradius wird unterschieden in Wohnviertel, Nachbarviertel und sonstiges weiteres Stadtgebiet. Um aus den vier betrachteten Aktivitäten einen umfassenden Kennwert für den durchschnittlichen Aktionsradius eines Befragten zu bilden, wird ein Modell für den Kennwert eines Aktionsradius entwickelt. Die Studie kommt zu dem Ergebnis, dass das Alter der Befragten einen signifikanten – wenn auch geringen – Einfluss auf den Aktionsradius hat. Das Haushaltsnettoeinkommen hat einen mit Einschränkung signifikanten, ebenfalls geringen Einfluss auf alltägliche Aktivitäten der Befragten.
Volumerendering ist eine Darstellungstechnik, um verschiedene räumliche Mess- und Simulationsdaten anschaulich, interaktiv grafisch darzustellen. Im folgenden Beitrag wird ein Verfahren vorgestellt, mehrere Volumendaten mit einem Architekturflächenmodell zu überlagern. Diese komplexe Darstellungsberechnung findet mit hardwarebeschleunigten Shadern auf der Grafikkarte statt. Im Beitrag wird hierzu der implementierte Softwareprototyp "VolumeRendering" vorgestellt. Neben dem interaktiven Berechnungsverfahren wurde ebenso Wert auf eine nutzerfreundliche Bedienung gelegt. Das Ziel bestand darin, eine einfache Bewertung der Volumendaten durch Fachplaner zu ermöglichen. Durch die Überlagerung, z. B. verschiedener Messverfahren mit einem Flächenmodell, ergeben sich Synergien und neue Auswertungsmöglichkeiten. Abschließend wird anhand von Beispielen aus einem interdisziplinären Forschungsprojekt die Anwendung des Softwareprototyps illustriert.