@article{BanihaniRabczukAlmomani, author = {Banihani, Suleiman and Rabczuk, Timon and Almomani, Thakir}, title = {POD for real-time simulation of hyperelastic soft biological tissue using the point collocation method of finite spheres}, series = {Mathematical Problems in Engineering}, journal = {Mathematical Problems in Engineering}, doi = {10.1155/2013/386501}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170413-31203}, abstract = {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.}, subject = {Chirurgie}, language = {en} } @article{Cervantes, author = {Cervantes, Juan}, title = {Ideology, neoliberalism and sustainable development}, series = {Human Geographies}, journal = {Human Geographies}, doi = {10.5719/hgeo.2013.72.25}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170418-31300}, pages = {25 -- 34}, abstract = {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.}, subject = {Neoliberalismus}, language = {en} } @article{JiangZhuangRabczuk, author = {Jiang, Jin-Wu and Zhuang, Xiaoying and Rabczuk, Timon}, title = {Orientation dependent thermal conductance in single-layer MoS 2}, series = {Scientific Reports}, journal = {Scientific Reports}, doi = {10.1038/srep02209}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170418-31417}, abstract = {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.}, subject = {Mechanische Eigenschaft}, language = {en} } @article{LorekWagner, author = {Lorek, Andreas and Wagner, Norbert}, title = {Supercooled interfacial water in fine-grained soils probed by dielectric spectroscopy}, series = {Cryosphere}, journal = {Cryosphere}, doi = {10.25643/bauhaus-universitaet.3149}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170425-31490}, pages = {1839 -- 1855}, abstract = {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.}, subject = {Wasser}, language = {en} } @article{LorekWagner, author = {Lorek, Andreas and Wagner, Norman}, title = {Supercooled interfacial water in fine grained soils probed by dielectric spectroscopy}, series = {Cryosphere}, journal = {Cryosphere}, doi = {10.5194/tc-7-1839-2013}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170516-31840}, pages = {1839 -- 1855}, abstract = {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.}, subject = {Grundwasser}, language = {en} } @article{MullisSchipper, author = {Mullis, Daniel and Schipper, Sebastian}, title = {Die postdemokratische Stadt zwischen Politisierung und Kontinuit{\"a}t. Oder ist die Stadt jemals demokratisch gewesen?}, series = {sub\urban. Zeitschrift f{\"u}r Kritische Stadtforschung}, volume = {2013}, journal = {sub\urban. Zeitschrift f{\"u}r Kritische Stadtforschung}, number = {Band 1, Heft 2}, publisher = {sub\urban e.V.}, address = {Berlin}, doi = {10.36900/suburban.v1i2.97}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220112-45600}, pages = {79 -- 100}, abstract = {In der kritischen Stadtforschung wird die These der postdemokratischen Stadt aktuell immer wieder aufgegriffen und dabei eng mit Prozessen der Neoliberalisierung verkn{\"u}pft. Ausgehend von einer kritischen Diskussion der konzeptionellen Zug{\"a}nge bei Colin Crouch und Jacques Ranci{\`e}re geht der Beitrag anhand der Geschichte der kommunalen Selbstverwaltung in Frankfurt am Main dem Gehalt der beiden Begriffsbestimmungen in der konkreten historischen Analyse nach. Verwiesen wird dabei auf die unterschiedliche Analysetiefe der beiden Konzepte. Entgegen der bei Crouch vorherrschenden Annahme, dass es vor der neoliberalen Stadt eine demokratische Form st{\"a}dtischen Regierens gegeben hat, wird unter R{\"u}ckbezug auf die Argumentation Ranci{\`e}res zur Demokratie betont, dass der Fordismus keinesfalls als egalit{\"a}rer, inklusiver oder demokratischer charakterisiert werden kann. Vielmehr vertreten wir die These, dass die fordistische Stadt zwar aus anderen Gr{\"u}nden, aber vom Grundsatz her nicht weniger postdemokratisch gewesen ist als die neoliberale der Gegenwart und dass die demokratischen Momente am ehesten in den Br{\"u}chen und Spalten der sozialen Konflikte der 1970er und 1980er Jahre gefunden werden k{\"o}nnen.}, subject = {Stadtplanung}, language = {de} } @article{Stratmann, author = {Stratmann, Bernhard}, title = {Wissenschaft, Forschung und Forschungsprozess - Eine Einf{\"u}hrung}, doi = {10.25643/bauhaus-universitaet.1849}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20130212-18498}, pages = {1 -- 33}, abstract = {Der Artikel behandelt f{\"u}nf f{\"u}r das wissenschaftliche Arbeiten besonders relevante Themenfelder: 1) Ziele und Gegenstand wissenschaftlichen Arbeitens, 2) der Zusammenhang von Wissenschaft, Erkenntnis und Fortschritt, 3) eine Darstellung der Forschungslandschaft in Deutschland unter Ber{\"u}cksichtigung der Wissenschaftsorganisation, 4) eine ausf{\"u}hrliche, praxisorientierte Erl{\"a}uterung des typischen Ablaufs eines Forschungsprozesses, 5) eine Skizze zur literaturbasierten Forschung. Der Beitrag stellte zahlreiche Bez{\"u}ge zur Stadtforschung her und nutzt Beispiele zur Illustration der Inhalte.}, subject = {Forschungsprozess}, language = {de} } @article{VuBacNguyenXuanChenetal., author = {Vu-Bac, N. and Nguyen-Xuan, Hung and Chen, Lei and Lee, C.K. and Zi, Goangseup and Zhuang, Xiaoying and Liu, G.R. and Rabczuk, Timon}, title = {A phantom-node method with edge-based strain smoothing for linear elastic fracture mechanics}, series = {Journal of Applied Mathematics}, journal = {Journal of Applied Mathematics}, doi = {10.1155/2013/978026}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170426-31676}, abstract = {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.}, subject = {Finite-Elemente-Methode}, language = {en} } @article{VoelkerBeckmannKoehlmannetal., author = {V{\"o}lker, Conrad and Beckmann, Julia and Koehlmann, Sandra and Kornadt, Oliver}, title = {Occupant requirements in residential buildings - an empirical study and a theoretical model}, series = {Advances in Building Energy Research}, journal = {Advances in Building Energy Research}, number = {7 (1)}, doi = {10.25643/bauhaus-universitaet.3813}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20181015-38137}, pages = {35 -- 50}, abstract = {Occupant needs with regard to residential buildings are not well known due to a lack of representative scientific studies. To improve the lack of data, a large scale study was carried out using a Post Occupancy Evaluation of 1,416 building occupants. Several criteria describing the needs of occupants were evaluated with regard to their subjective level of relevance. Additionally, we investigated the degree to which deficiencies subjectively exist, and the degree to which occupants were able to accept them. From the data obtained, a hierarchy of criteria was created. It was found that building occupants ranked the physiological needs of air quality and thermal comfort the highest. Health hazards such as mould and contaminated building materials were unacceptable for occupants, while other deficiencies were more likely to be tolerated. Occupant satisfaction was also investigated. We found that most occupants can be classified as satisfied, although some differences do exist between different populations. To explain the relationship between the constructs of what we call relevance, acceptance, deficiency and satisfaction, we then created an explanatory model. Using correlation and regression analysis, the validity of the model was then confirmed by applying the collected data. The results of the study are both relevant in shaping further research and in providing guidance on how to maximize tenant satisfaction in real estate management.}, subject = {Post Occupancy Evaluation}, language = {en} } @article{WagnerBoreRobinetetal., author = {Wagner, Norman and Bore, Thierry and Robinet, Jean-Charles and Coelho, Daniel and Taillade, Frederic and Delepine-Lesoille, Sylvie}, title = {Dielectric relaxation behavior of Callovo-Oxfordian clay rock: A hydraulic-mechanical-electromagnetic coupling approach}, series = {Journal of Geophysical Research: Solid Earth}, journal = {Journal of Geophysical Research: Solid Earth}, doi = {10.1002/jgrb.50343}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170428-31681}, pages = {4729 -- 4744}, abstract = {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.}, subject = {Lehm}, language = {en} }