Life Cycle Integration of Building Information Modeling in Infrastructure Projects

Building Information Modeling (BIM) can provide solutions to many challenges of asset management, such as missing data, incompatible software, and an unclear business process. However, current implementation of BIM in infrastructure projects has only considers limited factors, such as technology application and digital information delivery, while issues of system compatibility and information needs are still missing. Different aspects of a business are interdependent and an incompatible development of various factors might result in different levels of BIM implementation or even project failure. Comprehensive research is needed to explore the key factors and challenges of BIM implementation in infrastructure projects. This study conducted interviews and surveys with key stakeholders of infrastructure projects to explore the challenges and potential solutions of BIM implementation. Interviews were conducted with 37 professionals and surveys were conducted with 102 professional stakeholders, including owners, designers, contractors, and software vendors. Four main factors, challenges, and potential solutions were identified from content analysis of the interviews and further validated by the surveys. These factors include process factor (when), technology factor (how), people factor (who), and information factor (what). Corresponding solutions are proposed to refine the current workflow and practices

Life Cycle Integration of Building Information Modeling in Infrastructure Projects

Building Information Modeling (BIM) can provide solutions to many challenges of asset management, such as missing data, incompatible software, and an unclear business process. However, current implementation of BIM in infrastructure projects has only considers limited factors, such as technology application and digital information delivery, while issues of system compatibility and information needs are still missing. Different aspects of a business are interdependent and an incompatible development of various factors might result in different levels of BIM implementation or even project failure. Comprehensive research is needed to explore the key factors and challenges of BIM implementation in infrastructure projects. This study conducted interviews and surveys with key stakeholders of infrastructure projects to explore the challenges and potential solutions of BIM implementation. Interviews were conducted with 37 professionals and surveys were conducted with 102 professional stakeholders, including owners, designers, contractors, and software vendors. Four main factors, challenges, and potential solutions were identified from content analysis of the interviews and further validated by the surveys. These factors include process factor (when), technology factor (how), people factor (who), and information factor (what). Corresponding solutions are proposed to refine the current workflow and practices

A robust free-standing MoS2/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) film for supercapacitor applications

Two-dimensional molybdenum disulfide (MoS2) is a promising energy storage material due to its high surface area and unique electronic structure. Free-standing flexible MoS2-based electrode is of importance for use in flexible energy storage devices, whereas there are limited reports available. In this work we developed a robust hybrid film, MoS2 incorporated with highly conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate). This free-standing film possesses excellent mechanical properties with a fracture strength of 18.0 MPa and a Young\u27s modulus of 2.0 GPa. It can deliver a large volumetric capacitance of 141.4 F cm-3, a high volumetric energy density of 4.9 mWh cm-3, and a capacitance retention rate of 98.6% after 5000 charge/discharge cycles. This film has demonstrated its application in an all-solid-state bendable supercapacitor as well

A robust free-standing MoS2/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) film for supercapacitor applications

Two-dimensional molybdenum disulfide (MoS2) is a promising energy storage material due to its high surface area and unique electronic structure. Free-standing flexible MoS2-based electrode is of importance for use in flexible energy storage devices, whereas there are limited reports available. In this work we developed a robust hybrid film, MoS2 incorporated with highly conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate). This free-standing film possesses excellent mechanical properties with a fracture strength of 18.0 MPa and a Young\u27s modulus of 2.0 GPa. It can deliver a large volumetric capacitance of 141.4 F cm-3, a high volumetric energy density of 4.9 mWh cm-3, and a capacitance retention rate of 98.6% after 5000 charge/discharge cycles. This film has demonstrated its application in an all-solid-state bendable supercapacitor as well

Evaluation of Infrastructure-based Warning System on Driving Behaviors-A Roundabout Study

Smart intersections have the potential to improve road safety with sensing, communication, and edge computing technologies. Perception sensors installed at a smart intersection can monitor the traffic environment in real time and send infrastructure-based warnings to nearby travelers through V2X communication. This paper investigated how infrastructure-based warnings can influence driving behaviors and improve roundabout safety through a driving-simulator study - a challenging driving scenario for human drivers. A co-simulation platform integrating Simulation of Urban Mobility (SUMO) and Webots was developed to serve as the driving simulator. A real-world roundabout in Ann Arbor, Michigan was built in the co-simulation platform as the study area, and the merging scenarios were investigated. 36 participants were recruited and asked to navigate the roundabout under three danger levels (e.g., low, medium, high) and three collision warning designs (e.g., no warning, warning issued 1 second in advance, warning issued 2 seconds in advance). Results indicated that advanced warnings can significantly enhance safety by minimizing potential risks compared to scenarios without warnings. Earlier warnings enabled smoother driver responses and reduced abrupt decelerations. In addition, a personalized intention prediction model was developed to predict drivers' stop-or-go decisions when the warning is displayed. Among all tested machine learning models, the XGBoost model achieved the highest prediction accuracy with a precision rate of 95.56% and a recall rate of 97.73%.Comment: 23 pages, 10 figure

EINFLUSSE DES PRAGER PARLERKREISES AUF DIE ARCHITEKTONISCHE PLASTIK AUS ILOK

In elem maler ischen syrmischen Stacltchen I lok ani h o hen Ufer cler Donau, umgeben von mi t telalterlichen Mauern, steht clie trot z cler t u r k ischen Her rschaft ( 1 526.— 1688.) erhalten gebliebene Franziskanerkirche cles hl . Johann Kapistran. Diese Kirche, die f ruher ei n ancleres Patrozinium hat te, wurde einige Male umgebaut ,im 18. Jh. barockisiert, und Anfang cles 20 Jhs. neugotisch restauriert. Bei clieser Gelegenheit wurcle ihr architektonisch- plastischer Schmuck e n t fernt , c ler s i c ht s eit dem Jahr 1912. in Zagreb befindet ( jetzt im Hi stor ischen Museum) . ln der Ki rche verblieb cine Konsolemit cler Jahreszahl 1468., nach welcher vor e iner halben Jahrhundert J. Br unšmid auch die Ubrigen erhaltenen Konsolen in clie zweite Halfte des 15. Jhs. clatierte. De r S t i l e i n iger von ihnen spr icht j ecloch fur cine andere Entstehungszeit. Es werden anschliessend st i l istische Merkmale dreier clieser Denkmaler untersucht: einer Konsole mit Laubwerk (42x42x59 cm), einer Konsole mi t Teufelskopf (46x37x47 cm) und einer Konsole mit dem Kopfe eines Monstrums (29x48x48 cna), die alle aus Sanclstein gemeisselt sincI. Ein Vergleich mi t Ko nsolen in cler Kathedrale i n Prag, sowie auch nai t v erwancltem Mater ial i n Zagreb, Slowenien, Osterreich uncI i n Ungarn (Budapest), welches unter elena Einfluss c ler Werkstatt der Par ler i n Pr ag entstanden i s t , z e i gt , class auch clie Konsolen aus Ilok Zuge aufweisen, die fur elen von der prager Parlerwerkstatt gemeisselten architektonisch-plastischen Schmuck kennzeichnend sind. Es wircl vorausgesetzt, class cliese Einflusse nicht auf di rektem Wege von Prag nach I lok gelang sincI, sondern uber Buclapest. Dort haben — nach Gerevich — n ach elem Jahre 1385.,nachclem c!er Chor cler Katheclrale in Prag fer t iggestellt war , al tere Meister cler ersten Generation gearbeitet ( si e konnten etwa 60 Jahre alt gewesen sein). Diese Meister sincI wahrscheinlich auf j ener alteren St i lstufe stehengeblieben, die ihr e Werke f u r clie prager Katheclrale kennzeichnet, bevor sie in di e Wel t h i nausz ogen. Danti t k o nnt e ma n d i e archaischen Zuge der Konsolen aus Ilok erklaren, clie — b edingt durch clieubrigen Zustancle im Lancle — t rot z ihrer archaischen Zuge in clieser provinziellen Umgebung in c(er Zeit cles Ubergangs vom 14. ins 15. Jh. ent stanclen sein konnten. Als Vermi t t ler kamen Konig Sigisniuncl von Luxemburg uncI Nikola Gor janski i n Bet racht . Konig Sigismund war f i m J a hre 1394. elen Aufstancl Paližna\u27s uncI der Br uder Ho r vat n iecle, und I ehrte nach cler Schfacht bei Nikopolis im Jahre 1397. aus cler Gerangenschaft i n s ei n L anel zuruck. Nikola Gor janski, Sigismuncl\u27s treuer Anhanger, war Banus von Kroatien (1397.1401.), uncI sei t elem Jahr e 1402. der ma cht ige Palatin von Ungarn, elem unter v ielen ancleren Gutern auch I lok gehor te. Bis jetzt war Zagreb al s cler sgcllichste Punkt bekannt, l>is zu welchem clie Ein f lusse cler beruhnnten Werkstatt cler Parl in Prag reichten. Nach elem Dargelegten ware jetzt I lok i n suclostlicher Richtung cler entfernteste Punkt i n cler kunstlerischen Geographie Europas, bi s z u we l chem s ic h d i e Erfahrungen <lieser Werkstatt er st reckte

A Novel Double Cluster and Principal Component Analysis-Based Optimization Method for the Orbit Design of Earth Observation Satellites

The weighted sum and genetic algorithm-based hybrid method (WSGA-based HM), which has been applied to multiobjective orbit optimizations, is negatively influenced by human factors through the artificial choice of the weight coefficients in weighted sum method and the slow convergence of GA. To address these two problems, a cluster and principal component analysis-based optimization method (CPC-based OM) is proposed, in which many candidate orbits are gradually randomly generated until the optimal orbit is obtained using a data mining method, that is, cluster analysis based on principal components. Then, the second cluster analysis of the orbital elements is introduced into CPC-based OM to improve the convergence, developing a novel double cluster and principal component analysis-based optimization method (DCPC-based OM). In DCPC-based OM, the cluster analysis based on principal components has the advantage of reducing the human influences, and the cluster analysis based on six orbital elements can reduce the search space to effectively accelerate convergence. The test results from a multiobjective numerical benchmark function and the orbit design results of an Earth observation satellite show that DCPC-based OM converges more efficiently than WSGA-based HM. And DCPC-based OM, to some degree, reduces the influence of human factors presented in WSGA-based HM

Flutter reliability analysis of Xiangshan Harbor Highway Cable-Stayed Bridges in Service

With the development of bridge structures towards being light weight and having a large span , the overall flexibility, and, hence, wind sensitivity, of the bridge increases. Flutter is one of the pivotal factors considered in the design and operation stage for long-span cable-stayed bridges due to its devastating impact, often intrigued by relatively low instability caused by wind speed. This paper presents a reliability theory-based numerical analysis on bridge flutter stability and its influence law of key parameters using a real bridge, the Xiangshan Harbor highway cable-stayed bridge in China. The analysis starts with creating a full scale of finite element model for the bridge in service to calculate the flutter derivative and time-dominated combining rational function in order to obtain the critical-flutter wind speed, and then the aerodynamic self-excited forces on the bridge and flutter time-history response are calculated to identify the flutter critical wind speed. Further, the influence of key parameters for flutter reliability, including the stiffness of the main girder, wire breaking rate, damping ratio and cable breakage location are analyzed comprehensively to achieve the change law of critical flutter wind speed with these parameters. Considering the uncertainty of the actual parameters, these parameters are taken as random variables, and the reliability index and failure probability of bridge flutter are calculated according to their probability distribution and the Latin hypercube sampling method. On this basis, a few suggestions are put forward for flutter risk-control during the service of this cable-stayed bridge, which can further enhance the design theory for long-span flexible bridges

A novel electrode with multifunction and regeneration for highly efficient and stable symmetrical solid oxide cell

Authors acknowledge financial support from National Key Research & Development Project (2016YFE0126900), National Natural Science Foundation of China (51672095, U1910209), and China Scholarship Council (201806160178). The work is also partially supported by State Key Laboratory of Materials Processing and Die & Mould Technology, Huazhong University of Science and Technology (P2019-004).Symmetrical solid oxide cells (SSOCs) have been extensively recognized due to their simple cell configuration, low cost and reliability. High performance electrode is the key determinant of SSOCs. Herein, a multifunctional perovskite oxide La0.6Ca0.4Fe0.8Ni0.2O3-δ (LCaFN) is investigated as electrode for SSOCs. The results confirm that LCaFN shows excellent oxygen reduction reaction (ORR), oxygen evolution reaction (OER), carbon dioxide reduction reaction (CO2-RR) and hydrogen oxidation reaction (HOR) catalytic activity. In SOFC mode, the SSOCs with LCaFN achieve good electrochemical performance with maximum power density of 300 mW cm−2 at 800 °C. For pure CO2 electrolysis in SOEC mode, polarization resistance of 0.055 Ω cm2 and current density of 1.5 A cm−2 are achieved at 2.0 V at 800 °C. Besides, the cell shows excellent stability both in SOFC mode and SOEC mode. Most importantly, SSOCs with symmetrical LCaFN electrodes show robust and regenerative performance under anodic or cathodic process during the switching gas, showing the great reliability of the SSOCs. The results show that this novel electrode offers a promising strategy for operation of SSOCs.PostprintPeer reviewe