• Title/Summary/Keyword: Traffic Distribution

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Health monitoring of pedestrian truss bridges using cone-shaped kernel distribution

  • Ahmadi, Hamid Reza;Anvari, Diana
    • Smart Structures and Systems
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    • v.22 no.6
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    • pp.699-709
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    • 2018
  • With increasing traffic volumes and rising vehicle traffic, especially in cities, the number of pedestrian bridges has also increased significantly. Like all other structures, pedestrian bridges also suffer damage. In order to increase the safety of pedestrians, it is necessary to identify existing damage and to repair them to ensure the safety of the bridge structures. Owing to the shortcomings of local methods in identifying damage and in order to enhance the reliability of detection and identification of structural faults, signal methods have seen significant development in recent years. In this research, a new methodology, based on cone-shaped kernel distribution with a new damage index, has been used for damage detection in pedestrian truss bridges. To evaluate the proposed method, the numerical models of the Warren Type steel truss and the Arregar steel footbridge were used. Based on the results, the proposed method and damage index identified the damage and determined its location with a high degree of precision. Given the ease of use, the proposed method can be used to identify faults in pedestrian bridges.

The Impact of Auditor-Client Traffic Convenience on Earnings Management in China

  • YIN, Hong;DU, Yanbin
    • Asian Journal of Business Environment
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    • v.11 no.4
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    • pp.5-16
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    • 2021
  • Purpose: This study aims to investigate the impact of auditor-client traffic convenience on accrual -based and real earnings management of the client firms. Research design, data and methodology: Using a sample of firms listed in Shanghai and Shenzhen Stock Exchanges over the period of 2007 to 2018, this paper empirically investigates the association between auditor-client traffic convenience and earnings management. We use three measures of auditor-client traffic convenience: railway traffic convenience, expressway traffic convenience, and air traffic convenience. The accrual-based earnings management is measured by abnormal accruals estimated by industry and year using the Modified Jones Model. Results: Findings indicate that traffic convenience is conducive to detecting and restraining positive accrual earnings management and real earnings management. After changing the measurement of independent variable and dependent variable, including potential omitted variables, the results are statistically unchanged. Further, the research shows that traffic convenience can not only improve audit quality, but also lead to higher fee premiums. Auditors didn't share with clients the cost reduction benefits caused by traffic convenience. Conclusions: Traffic convenience provides auditors with easy access to the client firms, alleviating the information asymmetry and improving corporate earnings quality. The findings have implications for regulators, audit practitioners and stakeholders.

Development and Application of an Evaluation Method for a Freight Vehicle Route Management System (화물자동차 통행관리제도의 평가방법 개발 및 적용 (서울지역을 대상으로))

  • Kim, Yu-Chan;Park, Dong-Joo
    • Journal of Korean Society of Transportation
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    • v.26 no.4
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    • pp.17-28
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    • 2008
  • Favorable policies for freight vehicles (i.e., trucks), such as exclusive "Truck-ways," have been proposed, and at the same time restricted policies for freight vehicles have been suggested because transportation of goods by truck aggravates traffic congestion and environmental conditions in urban areas. This study discusses the limitations of assessment processes for freight vehicle route management systems which have been carried out from limited perspectives such as physical distribution efficiency and traffic circulation. The objective of this study is to propose an assessment method of truck route management systems in urban areas which includes more varied criteria. This research modified the two existing assessment indices of physical distribution efficiency and traffic circulation. In addition two new assessment indexes are proposed: (i) exposure indices for population directly influenced by nitrous oxide, a representative pollutant, and (ii) a friction index between trips for attending elementary school and freight vehicle trips. It was found that from the perspective of physical distribution efficiency and traffic circulation, the "before" alternative is better than "after". However, from the aspect of traffic safety and environmental impacts the "after" alternative is better than "before". It is expected that the proposed evaluation method in this study would be useful when identifying reasonable policies for truck route management in urban areas.

A Study on general logistic center of agriculture products for location selection model (농산물 종합물류센터조성을 위한 입지선정 평가요인 분석)

  • 김규창
    • Journal of Distribution Research
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    • v.3 no.1
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    • pp.145-158
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    • 1998
  • The selection of proposed sites for the general logistic center of agriculture products would be made the most suitable place by considering the spread of population as real consumers, the prospect of the demand, the expansion of traffic system, the regional, hourly and carring traffic volume and the use of land based urban planning, etc. As the preconsideration, the possible occupant companies have to be selected on the category of business and the district. After posing questions and having interview, several selected regions would be compared and analysed for deciding the most suitable place. The model for the general logistic center of agricultural products must be selected taking key factors approach for choosing key factors at first and referring to many documentary records. And the more, cooperating with the specialists for location selection and making objective questions to concerned companies, the most suitable place is selected by marking high score for the moderate land cost, the low traffic jam, the connection with the back cities and the possible expansion as the general logistic center of agriculture products.

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Asymptotic cell loss decreasing rate in an ATM multiplexer loaded with heterogeneous on-off sources

  • Choi, Woo-Yong;Jun, Chi-Hyuck
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1996.04a
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    • pp.543-546
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    • 1996
  • Recently, some research has been done to analyze the asymptotic behavior of queue length distribution in ATM (Asynchronous Transfer Mode) multiplexer. In this paper, we relate this asymptotic behavior with the asymptotic behavior of decreasing cell loss probability when the buffer capacity is increased. We find with reasonable assumptions that the asymptotic rate of queue length distribution is the same as that of decreasing cell loss probability. Even under different priority control schemes and traffic classes, we find that this asymptotic rate of the individual cell loss probability of each traffic class does not change. As a consequence, we propose the upper bound of cell loss probability of each traffic class when a priority control scheme is employed. This bound is computationally feasible in a real-time. The numerical examples will be provided to validate this finding.

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Dynamic Load-Balancing Algorithm Incorporating Flow Distributions and Service Levels for an AOPS Node

  • Zhang, Fuding;Zhou, Xu;Sun, Xiaohan
    • Journal of the Optical Society of Korea
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    • v.18 no.5
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    • pp.466-471
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    • 2014
  • An asynchronous optical packet-switching (AOPS) node with load-balancing capability can achieve better performance in reducing the high packet-loss ratio (PLR) and time delay caused by unbalanced traffic. This paper proposes a novel dynamic load-balancing algorithm for an AOPS node with limited buffer and without wavelength converters, and considering the data flow distribution and service levels. By calculating the occupancy state of the output ports, load state of the input ports, and priorities for data flow, the traffic is balanced accordingly. Simulations demonstrate that asynchronous variant data packets and output traffic can be automatically balanced according to service levels and the data flow distribution. A PLR of less than 0.01% can be achieved, as well as an average time delay of less than 0.46 ns.

A Study on the Appropriateness in Applying the Trip Distribution Model - in Kwangju City - (통행량 분포모형의 적용 타당성에 관한 연구 - 광주광역시를 중심으로 -)

  • Hwang, Eui-Jin
    • Journal of Korean Society for Geospatial Information Science
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    • v.12 no.3 s.30
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    • pp.43-50
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    • 2004
  • This study has an object of searching for appropriateness in applying the trip distribution model by studying the changes of the character of parameter which the model contains and by analyzing and evaluating trip distribution technique out of few steps of pre-estimate technique for the traffic demand through computer simulation centering around Kwangju. Method of this study is investigating the basic theory for trip distribution model and with this grounding, I rearranged it as research data for trip distribution model compatible for Kwangju, using data such as research data on actual state, the statistics annual report and basic plan for traffic full equipment of Kwangju. So, The most stable measure of the type of trip distribution of Kwangju city was produced in Fratar and Detroit model, however, gravity model has a little bit low reliance in sharing of estimation and actual survey although it is astringent in short period.

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A Study on the Performance Analysis of Broadband ISDN Traffic (광대역 ISDN의 트래픽 성능분석에 관한 연구)

  • 구창회;박광채;이재호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.7
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    • pp.980-988
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    • 1993
  • In this paper, performance of 8-ISDN traffic for the buffer size which is requested of important parameters in switch/multiplexer of B-ISDN with multimedia traffic is analyzed. Multimedia traffic is modeled as a traffic, which is composed of poisson distribution traffic and burst traffic with exponential/geometric ON time duration(Burst duration) Performance of traffic which is modeled as a multimedia traffic is analysed and buffer size, can provide the high quality service, is presented for the cell loss probability. It is simulated using event scheduling approach method which is provided by simulation package, PC SIMSCRIPT II.5. Simulation program is composed of PREAMBLE, MAIN, INITIAL, ARRIVAL, DEPARTURE and STOP·SIM modules. Specially, in case of mixed traffic simulation, ARRIVAL module is composed of ARRIVAL I and ARRIVAL II, and cells are generated independently by each module.

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Road Traffic Noise Assessment of the Urban Area using LiDAR Data (LiDAR 자료를 이용한 도심지의 도로 교통소음 영향평가)

  • Lee, Dong-Ha;Lee, Seung-Heon;Yun, Hong-Sic;Cho, Jae-Myung;We, Gwang-Jae
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2007.04a
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    • pp.475-478
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    • 2007
  • In this study, we estimated the effect of the traffic noise in urban area using the LiDAR data. The propagation of noise has a strong relationship between distance and shape of surface. Therefore, it is necessary to consider the distribution of buildings for estimating noise assessment in urban area because noise propagations will be affected by buildings. For this, we were developed DEM and DBM using the LiDAR data in order to analyze the propagation of traffic noise precisely in urban area. The level of traffic noise were calculated by investigating the real volume of traffic in study area. The SoundPLAN S/W and RLS90 algorithm was used for traffic noise assessment.

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An evaluation of Marine Traffic Congestion in Pusan Port by Simulation Method (부산항 해상교통 혼잡도 평가에 관하여)

  • 석상문;여기태;이홍걸;이철영
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 1998.10a
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    • pp.323-329
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    • 1998
  • In Pusan port, the studies, which analysis container cargo volumes by using forecasting methods and research about container logistics system, etc., have been continuously performed. But, in Pusan port, this study on an evaluation of traffic congestion has been scarcely performed until now. Especially, when changing and extending a berth, and constructing a new port, it is very important to examine this field. And it should be considered. Thus, this paper aims to analysis the effect of ship traffic condition in 2011, to evaluate marine traffic congestion, according to changing ship traffic volumes in Pusan port. To analysis it, we used simulation method and examined the results

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