• 제목/요약/키워드: Jiang model

검색결과 391건 처리시간 0.022초

BIM-GIS Interoperability for Highway Traffic Information Sharing

  • Hu, Xiaoqiang;Bao, Jieyi;Jiang, Yi;Li, Shuo
    • 국제학술발표논문집
    • /
    • The 9th International Conference on Construction Engineering and Project Management
    • /
    • pp.1051-1058
    • /
    • 2022
  • Information sharing is the main purpose of realizing interoperability between the application domains of Geographic Information System (GIS) and Building Information Modeling (BIM). This paper presents and describes the workflow of BIM-GIS interoperability for highway traffic information sharing. An innovative and automatic Dynamo process was presented to transfer the shapes and attributes of the shapefile from GIS to BIM. On the basis of the transformed BIM model, the detailed traffic data was added and expressed in the form of families and sheets to expand traffic information. Then, the shapes of the model were swept as solid geometries in the BIM environment applying Dynamo. The expanded BIM model was transferred back to the GIS system using the Industry Foundation Classes (IFC) scheme. The mutual communication between BIM and GIS was achieved based on Dynamo and IFC. This paper provides a convenient and feasible way to realize BIM-GIS interoperability for highway traffic information sharing according to the characteristics of highways in terms of graphic expression and model creation.

  • PDF

Model test method for dynamic responses of bridge towers subjected to waves

  • Chengxun Wei;Songze Yu;Jiang Du;Wenjing Wang
    • Structural Engineering and Mechanics
    • /
    • 제86권6호
    • /
    • pp.705-714
    • /
    • 2023
  • In order to establish a dynamic model test method of bridge pylons subjected to ocean waves, the similarity method of hydroelastic model test for bridge pylons were analyzed systematically, and a model design and production method was proposed. Using this method, a dynamic test model of a bridge pylon was made, and then a free vibration test on the model structure and a dynamic response test of the model structure under wave actions were conducted in a wave flume. The results of the free vibration test show that the primary natural frequencies of the structure by the model test are close to the design frequencies of the prototype structure, indicating that the dynamic characteristics of the bridge pylon are well simulated by the model structure. The results of the dynamic response test show that wave induced base shear forces and motion responses on the model structure are consistent with the numerical results of the prototype structure. The model test results confirm that the proposed model test design method is feasible and applicable. It has application and reference significances for model testing studies of such marine bridge structures.

The System Performance of Wireless CSMA/CA Protocol with Capture Effect

  • Dai, Jiang-Whai
    • Journal of Communications and Networks
    • /
    • 제6권3호
    • /
    • pp.226-234
    • /
    • 2004
  • This work presents a deterministic channel that rules according to inverse a power propagation law. The proposed channel model allows us to derive the lower bound and upper bound of packet's capture probability in Rayleigh fading and shadowing cellular mobile system. According to these capture probabilities, we analyze the system performance in the case of finite stations and finite communicated coverage of a base station. We also adopted a dynamic backoff window size to discuss the robustness of IEEE 802.11 draft standard. Some suggestions and conclusions from numerical results are given to establish the more strong CSMA/CA protocol.

A spatial displacement model for horizontally curved beams

  • Jiang, Z.G.;Luo, Q.Z.;Tang, J.
    • Structural Engineering and Mechanics
    • /
    • 제15권1호
    • /
    • pp.151-157
    • /
    • 2003
  • A new approach to the analysis of horizontally curved beams is presented in this paper. The proposed method simplifies a two-dimensional structure into a one-dimensional structure just like a normal beam for structural analysis and, therefore, reduces the computational effort significantly.

A New Solution for Stochastic Optimal Power Flow: Combining Limit Relaxation with Iterative Learning Control

  • Gong, Jinxia;Xie, Da;Jiang, Chuanwen;Zhang, Yanchi
    • Journal of Electrical Engineering and Technology
    • /
    • 제9권1호
    • /
    • pp.80-89
    • /
    • 2014
  • A stochastic optimal power flow (S-OPF) model considering uncertainties of load and wind power is developed based on chance constrained programming (CCP). The difficulties in solving the model are the nonlinearity and probabilistic constraints. In this paper, a limit relaxation approach and an iterative learning control (ILC) method are implemented to solve the S-OPF model indirectly. The limit relaxation approach narrows the solution space by introducing regulatory factors, according to the relationship between the constraint equations and the optimization variables. The regulatory factors are designed by ILC method to ensure the optimality of final solution under a predefined confidence level. The optimization algorithm for S-OPF is completed based on the combination of limit relaxation and ILC and tested on the IEEE 14-bus system.

Simulating the Response of a 10-Storey Steel-Framed Building under Spreading Multi-Compartment Fires

  • Jiang, Jian;Zhang, Chao
    • 국제초고층학회논문집
    • /
    • 제7권4호
    • /
    • pp.389-396
    • /
    • 2018
  • This paper presents a numerical investigation on the structural response of a multi-story building subjected to spreading multi-compartment fires. A recently proposed simple fire model has been used to simulate two spreading multi-compartment fire scenarios in a 10-story steel-framed office building. By assuming simple temperature rising and distribution profiles in the fire exposed structural components (steel beams, steel column and concrete slabs), finite element simulations using a three-dimensional structural model has been carried out to study the failure behavior of the whole structure in two multi-compartment fire conditions and also in a standard fire condition. The structure survived the standard fire but failed in the multi-compartment fire. Whilst more accurate fire models and heat transfer models are needed to better predict the behaviors of structures in realistic fires, the current study based on very simple models has demonstrated the importance and necessity of considering spreadingmulti-compartment fires in fire resistance design of multi-story buildings.

Sensor Density for Full-View Problem in Heterogeneous Deployed Camera Sensor Networks

  • Liu, Zhimin;Jiang, Guiyan
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제15권12호
    • /
    • pp.4492-4507
    • /
    • 2021
  • In camera sensor networks (CSNs), in order to better identify the point, full-view problem requires capture any facing direction of target (point or intruder), and its coverage prediction and sensor density issues are more complicated. At present, a lot of research supposes that a large number of homogeneous camera sensors are randomly distributed in a bounded square monitoring region to obtain full-view rate which is close to 1. In this paper, we deduce the sensor density prediction model in heterogeneous deployed CSNs with arbitrary full-view rate. Aiming to reduce the influence of boundary effect, we introduce the concepts of expanded monitoring region and maximum detection area. Besides, in order to verify the performance of the proposed sensor density model, we carried out different scenarios in simulation experiments to verify the theoretical results. The simulation results indicate that the proposed model can effectively predict the sensor density with arbitrary full-view rate.

CAN TRUST BETWEEN AN OWNER AND A CONTRACTOR BE ESTABLISHED: A PRINCIPAL-AGENT PERSPECTIVE

  • Jiang-wei Xu;Sungwoo Moon
    • 국제학술발표논문집
    • /
    • The 3th International Conference on Construction Engineering and Project Management
    • /
    • pp.1474-1478
    • /
    • 2009
  • The cooperation and trust among the project participants play a critical role in the success or failure of any delivery system in construction industry. But it is very difficult to establish trust between an owner and a contractor when rational people only pursue only their own material self-interest. Based on the principal-agent theory, this paper will introduce the altruistic behavior into the traditional principal-agent model, and model the reciprocal behavior between the owner and contractor. We will show that both the owner and the contractor benefit from their reciprocal behavior, and hence trust establishing between them is possible. More importantly, we will proof that the higher the project uncertainty is, the more important trust establishing is.

  • PDF

Dexmedetomidine alleviates blood-brain barrier disruption in rats after cerebral ischemia-reperfusion by suppressing JNK and p38 MAPK signaling

  • Canmin Zhu;Dili Wang;Chang Chang;Aofei Liu;Ji Zhou;Ting Yang;Yuanfeng Jiang;Xia Li;Weijian Jiang
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제28권3호
    • /
    • pp.239-252
    • /
    • 2024
  • Dexmedetomidine displays multiple mechanisms of neuroprotection in ameliorating ischemic brain injury. In this study, we explored the beneficial effects of dexmedetomidine on blood-brain barrier (BBB) integrity and neuroinflammation in cerebral ischemia/reperfusion injury. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 1.5 h and reperfusion for 24 h to establish a rat model of cerebral ischemia/reperfusion injury. Dexmedetomidine (9 ㎍/kg) was administered to rats 30 min after MCAO through intravenous injection, and SB203580 (a p38 MAPK inhibitor, 200 ㎍/kg) was injected intraperitoneally 30 min before MCAO. Brain damages were evaluated by 2,3,5-triphenyltetrazolium chloride staining, hematoxylin-eosin staining, Nissl staining, and brain water content assessment. BBB permeability was examined by Evans blue staining. Expression levels of claudin-5, zonula occludens-1, occludin, and matrix metalloproteinase-9 (MMP-9) as well as M1/M2 phenotypes-associated markers were assessed using immunofluorescence, RT-qPCR, Western blotting, and gelatin zymography. Enzyme-linked immunosorbent assay was used to examine inflammatory cytokine levels. We found that dexmedetomidine or SB203580 attenuated infarct volume, brain edema, BBB permeability, and neuroinflammation, and promoted M2 microglial polarization after cerebral ischemia/reperfusion injury. Increased MMP-9 activity by ischemia/reperfusion injury was inhibited by dexmedetomidine or SB203580. Dexmedetomidine inhibited the activation of the ERK, JNK, and p38 MAPK pathways. Moreover, activation of JNK or p38 MAPK reversed the protective effects of dexmedetomidine against ischemic brain injury. Overall, dexmedetomidine ameliorated brain injury by alleviating BBB permeability and promoting M2 polarization in experimental cerebral ischemia/reperfusion injury model by inhibiting the activation of JNK and p38 MAPK pathways.

A hardening model considering grain size effect for ion-irradiated polycrystals under nanoindentation

  • Liu, Kai;Long, Xiangyun;Li, Bochuan;Xiao, Xiazi;Jiang, Chao
    • Nuclear Engineering and Technology
    • /
    • 제53권9호
    • /
    • pp.2960-2967
    • /
    • 2021
  • In this work, a new hardening model is proposed for the depth-dependent hardness of ion-irradiated polycrystals with obvious grain size effect. Dominant hardening mechanisms are addressed in the model, including the contribution of dislocations, irradiation-induced defects and grain boundaries. Two versions of the hardening model are compared, including the linear and square superposition models. A succinct parameter calibration method is modified to parametrize the models based on experimentally obtained hardness vs. indentation depth curves. It is noticed that both models can well characterize the experimental data of unirradiated polycrystals; whereas, the square superposition model performs better for ion-irradiated materials, therefore, the square superposition model is recommended. In addition, the new model separates the grain size effect from the dislocation hardening contribution, which makes the physical meaning of fitted parameters more rational when compared with existing hardness analysis models.