• Title/Summary/Keyword: Critical path

Search Result 602, Processing Time 0.026 seconds

Detection of Illegal U-turn Vehicles by Optical Flow Analysis (옵티컬 플로우 분석을 통한 불법 유턴 차량 검지)

  • Song, Chang-Ho;Lee, Jaesung
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.39C no.10
    • /
    • pp.948-956
    • /
    • 2014
  • Today, Intelligent Vehicle Detection System seeks to reduce the negative factors, such as accidents over to get the traffic information of existing system. This paper proposes detection algorithm for the illegal U-turn vehicles which can cause critical accident among violations of road traffic laws. We predicted that if calculated optical flow vectors were shown on the illegal U-turn path, they would be cause of the illegal U-turn vehicles. To reduce the high computational complexity, we use the algorithm of pyramid Lucas-Kanade. This algorithm only track the key-points likely corners. Because of the high computational complexity, we detect center lane first through the color information and progressive probabilistic hough transform and apply to the around of center lane. And then we select vectors on illegal U-turn path and calculate reliability to check whether vectors is cause of the illegal U-turn vehicles or not. Finally, In order to evaluate the algorithm, we calculate process time of the type of algorithm and prove that proposed algorithm is efficiently.

The Effect of Social Support on Elderly Women's Quality of Life (여성노인의 사회적 지지가 삶의 질에 미치는 영향)

  • Hong, Sung-Hee
    • Journal of Family Resource Management and Policy Review
    • /
    • v.19 no.2
    • /
    • pp.1-26
    • /
    • 2015
  • The purpose of this study was to analyze the quality of life (QoL) of elderly women and the effect of social support on their QoL. The data were used 'urvey on the Elderly in 2011', which was held from 'Ministry of Health & Welfare' and 'Korea Institute for Health and Social Affairs'. Among the total 15,146 respondents, 3,880 of elderly women whose age was over 65, and who did not live together with their married children were included in the analysis. Multiple regression analysis and path analysis were used to analyze the research model. The findings were as follows. First, from the fact that the elderly women showed the highest mean in 'contact frequency with friends' among social support, it seemed that the elderly women contacted their friends more than their children in their old age. Among the support types from their children, elderly women received emotional support, physical support, instrumental support in order and irregular cash as a way of economic support. Second, from the regression results, the most critical factor that affected the QoL of elderly women was 'subjective physical condition level' and 'subjective standard of living' comes next. Third, the most important factor was 'subjective standard of living' from path analysis results, and 'subjective physical condition level' and 'total amount of annual income' in order. Also, social supports such as 'phone call contact frequency with children', 'emotional support from children', phone call contact frequency with relatives', 'phone call contact frequency with friends' positively affected the QoL of elderly women. Therefore, raising social supports from children, relatives, and friends positively contributes to improve the QoL of elderly women directly and indirectly. The results show that social supporters, which is a part of the structural aspects of social support, and types of social support, which lies in functional aspects, directly affect QoL of the elderly women and turn out to be factors that improve the QoL as mediating variables. It is concluded that the social supports can be the most important resources that make up declining personal and social resources in old age and maintain the QoL of elderly women.

Development of Stochastic Decision Model for Estimation of Optimal In-depth Inspection Period of Harbor Structures (항만 구조물의 최적 정밀점검 시기 추정을 위한 추계학적 결정모형의 개발)

  • Lee, Cheol-Eung
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.28 no.2
    • /
    • pp.63-72
    • /
    • 2016
  • An expected-discounted cost model based on RRP(Renewal Reward Process), referred to as a stochastic decision model, has been developed to estimate the optimal period of in-depth inspection which is one of critical issues in the life-cycle maintenance management of harbor structures such as rubble-mound breakwaters. A mathematical model, which is a function of the probability distribution of the service-life, has been formulated by simultaneously adopting PIM(Periodic Inspection and Maintenance) and CBIM(Condition-Based Inspection and Maintenance) policies so as to resolve limitations of other models, also all the costs in the model associated with monitoring and repair have been discounted with time. From both an analytical solution derived in this paper under the condition in which a failure rate function is a constant and the sensitivity analyses for the variety of different distribution functions and conditions, it has been confirmed that the present solution is more versatile than the existing solution suggested in a very simplified setting. Additionally, even in that case which the probability distribution of the service-life is estimated through the stochastic process, the present model is of course also well suited to interpret the nonlinearity of deterioration process. In particular, a MCS(Monte-Carlo Simulation)-based sample path method has been used to evaluate the parameters of a damage intensity function in stochastic process. Finally, the present stochastic decision model can satisfactorily be applied to armor units of rubble mound breakwaters. The optimal periods of in-depth inspection of rubble-mound breakwaters can be determined by minimizing the expected total cost rate with respect to the behavioral feature of damage process, the level of serviceability limit, and the consequence of that structure.

Characteristics of Buckling Load and Bifurcation in Accordance with Rise-span Ratio of Space Truss Considering Initial Imperfection (초기 불완전성을 고려한 공간 트러스의 분기좌굴과 라이즈-스팬 비에 따른 임계하중 특성)

  • Lee, Seung-Jae;Shon, Su-Deok
    • Journal of Korean Society of Steel Construction
    • /
    • v.24 no.3
    • /
    • pp.337-348
    • /
    • 2012
  • This study investigated the characteristics of bifurcation and the instability due to the initial imperfection of the space truss, which is sensitive to the initial conditions, and the calculated buckling load by the analysis of Eigen-values and the determinant of tangential stiffness. A two-free nodes model, a star dome, and a three-ring dome model were selected as case studies in order to examine the unstable phenomenon due to the sensitivity to Eigen mode, and the influence of the rise-span ratio and the load parameter on the buckling load were analyzed. The sensitivity to the imperfection of the two-free nodes model changed the critical path after reaching the limit point through the bifurcation mode, and the buckling load level was reduced by the increase in the amount of imperfection. The two sensitive buckling patterns for the model can be explained by investigating the displaced position of the free node, and the asymmetric Eigen mode was a major influence on the unstable behavior due to the initial imperfection. The sensitive mode was similar to the in-extensional mechanism basis of the simplified model. Since the rise-span ratio was higher, the effect of local buckling is more prominent than the global buckling in the star dome, and bifurcation on the equilibrium path occurring as the value of the load parameter was higher. Additionally, the buckling load levels of the star dome and the three-ring model were about 50-70% and 80-90% of the limit point, respectively.

Signal Level Analysis of a Camera System for Satellite Application

  • Kong, Jong-Pil;Kim, Bo-Gwan
    • Proceedings of the KSRS Conference
    • /
    • 2008.10a
    • /
    • pp.220-223
    • /
    • 2008
  • A camera system for the satellite application performs the mission of observation by measuring radiated light energy from the target on the earth. As a development stage of the system, the signal level analysis by estimating the number of electron collected in a pixel of an applied CCD is a basic tool for the performance analysis like SNR as well as the data path design of focal plane electronic. In this paper, two methods are presented for the calculation of the number of electrons for signal level analysis. One method is a quantitative assessment based on the CCD characteristics and design parameters of optical module of the system itself in which optical module works for concentrating the light energy onto the focal plane where CCD is located to convert light energy into electrical signal. The other method compares the design\ parameters of the system such as quantum efficiency, focal length and the aperture size of the optics in comparison with existing camera system in orbit. By this way, relative count of electrons to the existing camera system is estimated. The number of electrons, as signal level of the camera system, calculated by described methods is used to design input circuits of AD converter for interfacing the image signal coming from the CCD module in the focal plane electronics. This number is also used for the analysis of the signal level of the CCD output which is critical parameter to design data path between CCD and A/D converter. The FPE(Focal Plane Electronics) designer should decide whether the dividing-circuit is necessary or not between them from the analysis. If it is necessary, the optimized dividing factor of the level should be implemented. This paper describes the analysis of the electron count of a camera system for a satellite application and then of the signal level for the interface design between CCD and A/D converter using two methods. One is a quantitative assessment based on the design parameters of the camera system, the other method compares the design parameters in comparison with those of the existing camera system in orbit for relative counting of the electrons and the signal level estimation. Chapter 2 describes the radiometry of the camera system of a satellite application to show equations for electron counting, Chapter 3 describes a camera system briefly to explain the data flow of imagery information from CCD and Chapter 4 explains the two methods for the analysis of the number of electrons and the signal level. Then conclusion is made in chapter 5.

  • PDF

The Relationship among Media use, Political cynicism, Voting Behavior in 2012 General Elections (2012 국회의원 총선에서 나타난 미디어 이용, 정치 냉소주의, 투표 참여 간의 관계에 관한 연구)

  • Kwon, Hyok-Nam
    • Korean journal of communication and information
    • /
    • v.60
    • /
    • pp.28-51
    • /
    • 2012
  • This study explored the influence of media use on the audiences' intention to vote as well as their political cynicism in 2012 General elections. I offered three research questions: Research Question 1: What is the impact of media use on the political cynicism? Research Question 2: What are the impact of political intersest, political knowledge, media malaise, political efficacy on the political cynicism? Research Question 3: What is the impact of political cynicism on vote behavior? This study analysed survey data. Based on the results of hierarchial regression analysis and path analysis(AMOS), Internet news use was found to have a significant impact on the political cynicism. But the use of newspaper, TV news were not related to political cynicism. The political efficacy decreased political cynicism effectively, The findings from this study indicate that the relationship between media use and political cynicism is contingent on many factors and that cynicism has a negligible impact on citizen participation. This study also found that persons higher in efficacy were less cynical than low in efficacy. This suggest that cynicism is not always bad thing, that it may in fact be an indication of "an interested and critical citizenry". In conclusion this study showed that we need more in-depth analyses on the relationships among attention to media use, political cynicism and voting behavior to activate political participation.

  • PDF

Computation of the Shortest Distance of Container Yard Tractor for Multi-Cycle System (다중 사이클 시스템을 위한 실시간 위치 기반 컨테이너 야드 트랙터 최단거리 계산)

  • Kim, Han-Soo;Park, Man-Gon
    • Journal of Korea Multimedia Society
    • /
    • v.13 no.1
    • /
    • pp.17-29
    • /
    • 2010
  • A container terminal productivity is maximized by a minimized time for processing containers. So, we have been elevated the container terminal productivity through an improvement of computing system, but there are a limitation because of problems for transportation management and method. A Y/T(Yard Tractor), which is a representative transportation, is able to do only one process, loading or unloading, at one time. So if the Y/T can do loading and unloading step by step at a same time, the processing time would be shortened. In this paper, we proposed an effective operating process of Y/T(Yard Tractor) Multi-Cycle System by applying RTLS(Real Time Location System) to Y/T(Yard Tractor) in order to improve the process of loading and unloading at the container terminal. For this, we described Multi-Cycle System. This system consists of a real time location of Y/T based on RTLS, an indicating of Y/T location in real time with GIS technology, and an algorithm(Dijkstra's algorithm) of the shortest distance. And we used the system in container terminal process and could improve the container terminal productivity. As the result of simulation for the proposed system in this paper, we could verify that 9% of driving distance was reduced compared with the existing rate and 19% of driving distance was reduced compared with the maximum rate. Consequently, we could find out the container performance is maximized.

The Impact of Competitive Environments on the Configuration of e-Biz Integration Determinants and the Business Performance (경쟁적 환경이 e-Biz통합의 결정요인 구성과 경영성과에 미치는 영향)

  • Han, Bong-Ho;Kim, Chul-Soo;Seo, Chang-Soo
    • Asia pacific journal of information systems
    • /
    • v.21 no.2
    • /
    • pp.59-87
    • /
    • 2011
  • These days, firms are focusing on the improvement of relationships with business partners. The supply chain integrations are taking critical role in improving the relationships with business partners. In accordance with the development of the IT technology, it became possible for firms not only to integrate inner parts of the organization, but also to integrate the company with other organizations in the supply chain. Therefore, in e-Biz environments, it is imperative for firms to strengthen the core capacity through the supply chain, and to precisely determine the components of the determinants of e-Business integration which impact the firm performance. This study analyzed determinants that have impacts on e-business integration in e-business capacity perspectives in competitive environments. This study based on the premise that the resources and capacities that Grant(1991) and Hart(1995) emphasized do not directly influence the corporate performance. This study focused on the fact that corporate must create core competencies based on these capacities to establish competitive edge. Therefore, this study model analyzed to find out which e-Biz competencies are needed to integrate e-Biz according to competitive environment elements. This study designed to empirically analyze the impact of the e-Biz competencies to the e-Biz integration and to the corporate performance. Independent variables of this study-IT management, partner management, e-Biz knowledge, e-Biz establishment and proliferation, process innovation-are selected based on precedent studies on e-Biz competencies. We selected intermediate variables to verify that e-Biz competencies do not have direct impact on the corporate performance, but have impact on the e-Biz integration, which is intermediate effect. That is to verify that if the components of supply chain improve the integration level using e-Biz competencies, the overall supply chain performances will improve. Dependent variables are selected to verify that e-Biz integration has impacts on corporate performances. This study used factor analysis, path analysis, moderating effect analysis as statistical tests. First, we used exploratory factor analysis and confirmatory factor analysis to analyze reliability and validity. Because e-Biz competencies are presented variously by preceding studies, we used SPSS16.0 to verify if survey questionnaire used by theoretical backgrounds is properly composed. Second, we tested the property of structure model by AMOS. We did path analysis using AMOS16.0 to test structure that is composed of e-Biz competencies and e-Biz integration. Last, we tested moderating effects of measure factors. We analyzed 163 domestic companies to find out many significant suggestive points. First, relationship improvement capacity, e-business knowledge sharing capacity with business partners, and process innovation capacity are adopted as determinants of differentiation and competitive edges against competing firms. Second, e-business knowledge sharing capacity, and process innovation capacity are analyzed as the determinants of e-business integration in the firm which demand fluctuation in the market is high. On the other hand, among the determinants that require capturing ideas on new products, and strengthening the technological power, process innovation capacity are adopted as the determinants. These results provide us the foundation that the determinants that we have analyzed can impact the supply chain integration strategies which take into account the competitive environments.

Developing algorithms for providing evacuation and detour route guidance under emergency conditions (재난.재해 시 대피 및 우회차량 경로 제공 알고리즘 개발)

  • Yang, Choong-Heon;Son, Young-Tae;Yang, In-Chul;Kim, Hyun-Myoung
    • International Journal of Highway Engineering
    • /
    • v.11 no.3
    • /
    • pp.129-139
    • /
    • 2009
  • The transportation network is a critical infrastructure in the event of natural and human caused disasters such as rainfall, snowfall, and terror and so on. Particularly, the transportation network in an urban area where a large number of population live is subject to be negatively affected from such events. Therefore, efficient traffic operation plans are required to assist rapid evacuation and effective detour of vehicles on the network as soon as possible. Recently, ubiquitous communication and sensor network technology is very useful to improve data collection and connection related emergency information. In this study, we develop a specific algorithm to provide evacuation route and detour information only for vehicles under emergency situations. Our algorithm is based on shortest path search technique and dynamic traffic assignment. We perform the case study to evaluate model performance applying hypothetical scenarios involved terror. Results show that the model successfully describe effective path for each vehicle under emergency situation.

  • PDF

The Asymptotic Throughput and Connectivity of Cognitive Radio Networks with Directional Transmission

  • Wei, Zhiqing;Feng, Zhiyong;Zhang, Qixun;Li, Wei;Gulliver, T. Aaron
    • Journal of Communications and Networks
    • /
    • v.16 no.2
    • /
    • pp.227-237
    • /
    • 2014
  • Throughput scaling laws for two coexisting ad hoc networks with m primary users (PUs) and n secondary users (SUs) randomly distributed in an unit area have been widely studied. Early work showed that the secondary network performs as well as stand-alone networks, namely, the per-node throughput of the secondary networks is ${\Theta}(1/\sqrt{n{\log}n})$. In this paper, we show that by exploiting directional spectrum opportunities in secondary network, the throughput of secondary network can be improved. If the beamwidth of secondary transmitter (TX)'s main lobe is ${\delta}=o(1/{\log}n)$, SUs can achieve a per-node throughput of ${\Theta}(1/\sqrt{n{\log}n})$ for directional transmission and omni reception (DTOR), which is ${\Theta}({\log}n)$ times higher than the throughput with-out directional transmission. On the contrary, if ${\delta}={\omega}(1/{\log}n)$, the throughput gain of SUs is $2{\pi}/{\delta}$ for DTOR compared with the throughput without directional antennas. Similarly, we have derived the throughput for other cases of directional transmission. The connectivity is another critical metric to evaluate the performance of random ad hoc networks. The relation between the number of SUs n and the number of PUs m is assumed to be $n=m^{\beta}$. We show that with the HDP-VDP routing scheme, which is widely employed in the analysis of throughput scaling laws of ad hoc networks, the connectivity of a single SU can be guaranteed when ${\beta}$ > 1, and the connectivity of a single secondary path can be guaranteed when ${\beta}$ > 2. While circumventing routing can improve the connectivity of cognitive radio ad hoc network, we verify that the connectivity of a single SU as well as a single secondary path can be guaranteed when ${\beta}$ > 1. Thus, to achieve the connectivity of secondary networks, the density of SUs should be (asymptotically) bigger than that of PUs.