TY - JOUR A1 - Nagel, Falk A1 - Simon, Flaviu A1 - Kümmel, Benjamin A1 - Bergmann, Jean Pierre A1 - Hildebrand, Jörg T1 - Optimization Strategies for Laser Welding High Alloy Steel Sheets JF - Physics Procedia N2 - 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. KW - Edelstahl KW - Laserschweißen KW - Laser Welding; CO2; Diode; Distortion; Finite Element Analysis; Thermal Analysis; Mechanical Analysis; Numerical Model Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170425-31554 SP - 1242 EP - 1251 ER - TY - JOUR A1 - Meyer-Kohlstock, Daniel A1 - Haupt, Thomas A1 - Heldt, Erik A1 - Heldt, Nils A1 - Kraft, Eckhard T1 - Biochar as Additive in Biogas-Production from Bio-Waste JF - ENERGIES N2 - 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. KW - Festphasen-Fermentation KW - Biogasanlage KW - Organischer Abfall Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170406-31119 ER - TY - JOUR A1 - Meel, Inder P. A1 - Satirasetthavee, Dussadee A1 - Kanitpong, Kunnawee A1 - Taneerananon, Pichai T1 - Using Czech TCT to Assess Safety Impact of Deceleration Lane at Thai U-turns JF - ENGINEERING JOURNAL-THAILAND N2 - 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. KW - Verkehrssicherheit KW - Highway Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170406-31097 SP - 121 EP - 135 ER - TY - JOUR A1 - Morgenthal, Guido A1 - Yamasaki, Y. T1 - Aerodynamic Behaviour of Very Long Cable-Stayed Bridges during Construction JF - Procedia Engineering N2 - 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. KW - Kabelbrücke KW - Windkanal KW - Cable-stayed bridges; wind engineering; wind tunnel testing; construction Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170425-31525 SP - 1463 EP - 1471 ER - TY - JOUR A1 - Chubukov, A. A1 - Kapitanov, Valeriy A1 - Monina, Olga A1 - Silyanov, Valentin A1 - Brannolte, Ulrich T1 - Calculation of Traffic Capacity of Signaled Intersections JF - Transportation Research Procedia 20 N2 - In order to calculate traffic capacity of signaled intersections, it was suggested to apply an approach based on the concept of congestions. The paper states examples of traffic capacity calculation. KW - Verkehr KW - congestion; signaled intersections; traffic capacity Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170401-30964 UR - http://www.sciencedirect.com/science/article/pii/S2352146517300327 SP - 125 EP - 131 ER - TY - JOUR A1 - Meel, Inder P. A1 - Brannolte, Ulrich A1 - Satirasetthavee, Dussadee A1 - Kanitpong, Kunnawee T1 - Safety impact of application of auxiliary lanes at downstream locations of Thai U-turns JF - IATSS Research N2 - 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. KW - Verkehrssicherheit KW - Beschleunigungsstreifen KW - Auxiliary lane; Conflict Indexes; Road safety; Traffic Conflict Technique; U-turn Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170401-31016 UR - http://www.sciencedirect.com/science/article/pii/S0386111216300140 ER - TY - JOUR A1 - Wang, Quan A1 - Arash, Behrouz T1 - Announcement of a virtual special issue on computational carbon nanoscience JF - Carbon N2 - 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. KW - Kohlenstoff KW - Nanowissenschaften KW - Verbundwerkstoff Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170428-31695 SP - 370 EP - 372 ER - TY - JOUR A1 - Bremer, K. A1 - Wollweber, M. A1 - Weigand, F. A1 - Rahlves, M. A1 - Kuhne, Michael A1 - Helbig, R. A1 - Roth, B. T1 - Fibre Optic Sensors for the Structural Health Monitoring of Building Structures JF - Procedia Technology 26 N2 - 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. KW - Structural Health Monitoring KW - crack sensor; fibre optic sensor; humidity sensor; SHM Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170331-30912 UR - http://www.sciencedirect.com/science/article/pii/S2212017316304121 SP - 524 EP - 529 ER - TY - JOUR A1 - Masood, R. A1 - Kharal, M. K. N. A1 - Nasir, A.R. T1 - Is BIM Adoption Advantageous for Construction Industry of Pakistan? JF - Procedia Engineering N2 - 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. KW - Building Information Modeling KW - Bauindustrie KW - Pakistan KW - BIM, BIM Adoption, BIM Advantages , Construction Industry, Pakistan Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170425-31509 SP - 229 EP - 238 ER - TY - JOUR A1 - Meunier, David A1 - Walther, Christoph A1 - Worsley, Tom A1 - Dahl, Alexander A1 - Le Maître, Hélène T1 - Evolutions of the Reference Values Used in Transport CBA National Guidelines of 3 Countries and What they Reveal JF - Transportation Research Procedia 13 N2 - The paper presents, analyses and compares the evolution of reference values used in national guidelines issued for cost-benefit analysis of transport infrastructure projects, over the last fifty years, in France, UK and Germany. KW - Verkehrsinfrastruktur KW - Kosten-Nutzen-Analyse KW - Richtlinien Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170406-31106 UR - http://www.sciencedirect.com/science/article/pii/S2352146516300114 SP - 100 EP - 113 ER -