Transverse Flexural Behaviour of Steel-Engineering Cementitious Composites (ECC) Composite Deck under Negative and Positive Bending Forces

Yanhua Guan,Jiajie Wu,Renjuan Sun,Hongzhi Zhang,Yanqiu Hu,Fei Wang 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.8

Orthotropic steel bridge deck system usually consists of an orthotropic steel deck and an asphalt overlay. Fatigue cracks of the orthotropic steel deck and premature damage of the asphalt overlay are frequently reported for such system. Engineering cementitious composites (ECC) was therefore proposed to replace the asphalt overlay to address the aforementioned issues. The current study presents an investigation on the transversal flexural behaviour of the ECC under bending forces. Influence of the bending force direction, cover thickness, the number of longitudinal reinforcement steel bars on the flexural performance was revealed. Responses with regard to the load-deflection curve, failure mode, the ultimate capacity, the cracking behaviour, the interfacial slip between ECC and steel deck and the nominal cracking stresses were analysed. The results showed that the load-deflection response under both negative and positive bending forces exhibits elastic stage, crack-developing stage and yield stage. Compared with the reinforcement ratio, cover thickness plays a more significant role on the flexural performances. When the cover thickness decreases from 35 mm to 25 mm, the peak load increases by 21% − 25%. ECC maintains its feature of being ductile, with high tensile and compressive strain capacity in the composite slab. From the design point of view, reducing the cover thickness and increasing the reinforcement ratio can improve the ultimate load and cracking stress, and reduce the internal slip, strain and crack width of the composite slab. It is expected that the current study can provide basic knowledge to the design and application of the steel-ECC composite deck system.

Application of Waste Plastic Disposals to Marine Diesel Engines

Wei haijun,Guan delin,Wang hongzhi 한국항해항만학회 2000 한국항해항만학회 학술대회논문집 Vol.5 No.2

This paper illustrates a new test and result of WPD oil applied to marine diesel engines. In recent years, we must make an effort to develop an advanced technique for recycling waste plastics in order to utilize scrapped plastics as fuel for diesel engine. It is very important and necessary for us to cope with the increasing calorific value and the growing need of environment protection. The experiment fuel oil was obtained by mixing of diesel oil, WPD and water.

Short-Term Holiday Travel Demand Prediction for Urban Tour Transportation: A Combined Model Based on STC-LSTM Deep Learning Approach

Wanying Li,Hongzhi Guan,Yan Han,Haiyan Zhu,Ange Wang 대한토목학회 2022 KSCE Journal of Civil Engineering Vol.26 No.9

Short-term prediction of holiday travel demand is a complex but key issue to the planning and management of tour transportation system in big cities. This paper develops an improved spatial and temporal correlation long short-term memory model (STC-LSTM) to forecast short-term holiday travel demand based on deep learning approach. Analysis results show six kinds of tourist flow correlations appears in different sets of tourist attractions, and 27.94 percent of the tourist attractions have mid- or high- positive tourist flow correlation with others, meaning that a positive synchronization mechanism exists between suburban tourist attractions in Beijing. The proposed model predicts the holiday travel demand on the basis of the historical data of the spatial and temporal related tourist flows, and the auxiliary data including meteorological data, temporal data, and Internet search index. Based on actual case study with tourist flow data of the suburban tourist attraction in Beijing, the proposed STC-LSTM is carried out to compared with other conventional prediction approaches. Results show that the proposed approach can improve the prediction accuracy and well capture the different spatial and temporal correlations of tourist flows.

Evolutionary Game Model of Private Capital Investment in Urban Public Transportation

Yunqiang Xue,Hongzhi Guan,Jonathan Corey,Heng Wei 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.9

To address the previous researches’ shortcomings on private capital investment in public transportation, a new private capital investment method in public transportation considering passenger value is proposed. An Evolutionary Game Model (EGM) is constructed to quantify the impacts of private capital investment. Evolutionary Game Theory (EGT) supposes players are bounded rational; therefore EGM is more in accordance with the real situation. Jinan city is detailed as a case study to show how public and private sectors change their strategies. Model results show that the proposed investment strategy is superior to the traditional one and is evolutionary stable, thus the strategy should be encouraged. The EGM established in this paper provides a quantitative analysis tool for administrators and researchers to guide investment strategies of private capital in public transportation and lays the foundation for further research.

Exploring Resident’s Daily Activity-Travel Behavior: Activity Pattern, Duration and Competition

Wanying Li,Hongzhi Guan,Yan Han,Haiyan Zhu,Pengfei Zhao 대한토목학회 2021 KSCE Journal of Civil Engineering Vol.25 No.8

This paper aims to deeply analyze the regularity of residents' daily activity-travel behaviors to help traffic management departments predict travel demand and evaluate transportation policies. Taking time use data in American as empirical analysis, the influencing factors such as residents’ activity pattern, duration and competition were discussed and analyzed based on the competing risk model. Results can be concluded that: a) people feel happy and meaningful during most of the activities, while they feel sad or pain in relatively rare occasions; b) there is no significant difference between young people and the elderly as for the total number of activities during one day; c) estimation results show that personal, household and activity characteristics have significant influence on activity duration and pattern, and the pattern of last activity (N) has a great influence on the occurrence of next activity (N+1); d) the competition between residents' daily activities is confirmed based on the competing risk model, and travel is closely related to various activities and can be seen as the derived demand of various activities. In all combinations of activity-travel chain schedule, personal - household (30.0%), household - recreation (25.9%), work - travel (45.2%), purchase - travel (33.7%), recreation - travel (22.5%), volunteer - travel (55.3%) and travel - purchase (28.4%) have the highest proportion respectively.

废塑料油在船用柴油机上的燃烧特性及适用性研究

魏海军,(Wei haijun),关,德林(Guan delin),王宏志(Wang hongzhi) 한국항해항만학회 2000 한국항해항만학회 학술대회논문집 Vol.5 No.2

This paper illustrates a new test and result of WPD oil applied to marine diesel engines. In recent years, we must make an effort to develop an advanced technique for recycling waste plastics in order to utilize scrapped plastics as fuel for diesel engine. It is very important and necessary for us to cope with the increasing calorific value and the growing need of environment protection. The experiment fuel oil was obtained by mixing of diesel oil, WPD and water.

Cooperative Optimization of Bus-Subway-Shared Bicycle Based on Uncertainty Theory

Yunqiang Xue,Tong He,Xiangming Yao,Bing Zhang,Hongzhi Guan,Yang Qiu 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.4

This research considered the uncertainty of the operation time of shared bicycle, constructed the urban coupling network, and established the optimization model for the cooperative operation of conventional buses, subways and shared bikes. In the programming model, the optimization objective is to minimize the total travel time of passengers, and by optimizing and adjusting the departure intervals of conventional buses and subways as well as the stopping time of vehicles, the travel efficiency of passengers is improved. The interchange cooperative system composed of Nanchang Metro Line 1 and Bus 520 and the surrounding shared bicycle concentration area was taken as the case study. According to the optimization results, the passenger waiting time, passenger transfer time, and total passenger on-board time are effectively reduced by 21.5%, 23.2%, and 7.37%; ultimately, the total travel time is reduced by 8.2% at a confidence level of 95%. Case analyses show that the conventional bus stopping time has the greatest impact on the total travel time of the passengers as compared to the other variables. The research is of positive practical significance for promoting the efficient and coordinated development of urban transportation networks and facilitating the travel of residents.

Detection of Listeria monocytogenes in CSF from Three Patients with Meningoencephalitis by Next-Generation Sequencing

Ming Yao,Jiali Zhou,Yicheng Zhu,Yinxin Zhang,Xia Lv,Ruixue Sun,Ao Shen,Haitao Ren,Liying Cui,Hongzhi Guan,Honglong Wu 대한신경과학회 2016 Journal of Clinical Neurology Vol.12 No.4

Background and Purpose Encephalitis caused by Listeria monocytogenes (L. monocyto¬genes) is rare but sometimes fatal. Early diagnosis is difficult using routine cerebrospinal flu¬id (CSF) tests, while next-generation sequencing (NGS) is increasingly being used for the detection and characterization of pathogens. Methods This study set up and applied unbiased NGS to detect L. monocytogenes in CSF collected from three cases of clinically suspected listeria meningoencephalitis. Results Three cases of patients with acute/subacute meningoencephalitis are reported. Magnetic resonance imaging and blood cultures led to a suspected diagnosis of L. monocy¬togenes, while the CSF cultures were negative. Unbiased NGS of CSF identified and se¬quenced reads corresponding to L. monocytogenes in all three cases. Conclusions This is the first report highlighting the feasibility of applying NGS of CSF as a diagnostic method for central nervous system (CNS) L. monocytogenes infection. Routine application of this technology in clinical microbiology will significantly improve diagnostic methods for CNS infectious diseases.