• Title/Summary/Keyword: Network efficiency

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Railway Governance and Power Structure in China

  • Lee, Jinjing
    • International Journal of Railway
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    • v.1 no.4
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    • pp.129-133
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    • 2008
  • Over the last $15{\sim}20$years, many countries have adopted policies of railway privatization to keep up with increasing competition from road and air transport. Although each country and case has its own history, market characteristics, political context as well as administrative process, railway privatizations (including railway restructure, concession etc.) in the west usually are accompanied with the establishment of new regulatory regimes. Therefore, railway governance has been innovating towards an interaction of government, regulator, industry bodies, user groups, trade unions and other interested groups within the regulatory framework. However, it is not the case in China. Although China had seen a partial privatization in some branch lines and is experiencing a much larger-scale privatization by establishing joint-ventures to build and operate high-speed passenger lines and implementing an asset-based securitization program, administrative control still occupies absolutely dominant position in the railway governance in China. Ministry of Railway (MOR) acts as the administrator, operator as well as regulator. There is no national policy that clearly positions railway in the transportation network and clarifies the role of government in railway development. There is also little participation from interested groups in the railway policy making, pricing, service standard or safety matter. Railway in China is solely governed by the mere executive agency. Efficiency-focused economic perspective explanation is far from satisfaction. A wider research perspective from political and social regime is of great potential to better explain and solve the problem. In the west, separation and constrains of power had long been established as a fundamental rule. In addition to internal separation of political power(legislation, execution and jurisdiction), rise of corporation in the 19th century and association revolution in the 20th century greatly fostered the growth of economic and social power. Therefore, political, social and economic organizations cooperate and compete with each other, which leads to a balanced and resonable power structure. While in China, political power, mainly party-controlled administrative power has been keeping a dominated position since the time of plan economy. Although the economic reform promoted the growth of economic power of enterprises, it is still not strong enough to compete with political power. Furthermore, under rigid political control, social organizations usually are affiliated to government, independent social power is still too weak to function. So, duo to the limited and slow reform in political and social regime in China, there is an unbalanced power structure within which political power is dominant, economic power expanding while social power still absent. Totally different power structure in China determines the fundamental institutional environment of her railway privatization and governance. It is expected that the exploration of who act behind railway governance and their acting strength (a power theory) will present us a better picture of railway governance as a relevant transportation mode. The paper first examines the railway governance in China and preliminarily establishes a linkage between railway governance and its fundamental institutional environment, i.e. power structure in a specific country. Secondly, the reason why there is no national policy in China is explored in the view of political power. In China, legislative power is more symbolic while party-controlled administrative power dominates political process and plays a fundamental role in Chinese railway governance. And then, in the part three railway finance reform is analyzed in the view of economic power, esp. the relationship of political power and economic power.

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Applicability for Detecting Trails by Using KOMPSAT Imagery (등산로 탐지를 위한 KOMPSAT 영상의 활용가능성)

  • Bae, Jinsu;Yim, Jongseo;Shin, Young Ho
    • Journal of the Korean Geographical Society
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    • v.50 no.6
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    • pp.607-619
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    • 2015
  • It is important to detect trails accurately for finding a proper management. We examined the applicability of KOMPSAT imagery to detect trails and found that it could be an efficient alternative to track trails correctly. We selected K2 and K3 imagery with different spatial resolution. Then, we processed each imagery to get NDVI, SAVI, and SC data. And then, we identified trails by object-based analysis and network analysis. Finally, we evaluated the potential trails with F-measurement and Jaccard coefficient which are based on correctness and completeness. The results show that the applicability is quite different in each case. Among them, especially the SC data with K3 shows the most highest value; correctness of detecting legal trails is 0.44 and completeness of that is 0.54. F-measurement and Jaccard coefficient are 0.49 and 0.32. In general, although there is a limit in detecting trails by using only KOMPSAT imagery, the usefulness of KOMPSAT imagery can be a higher considering its cost efficiency and availability of acquiring periodic data.

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A Study on the Communication of the Functional Family (기능적인 가족의 커뮤니케이션에 관한 이론적 접근)

  • 조윤경
    • Journal of Families and Better Life
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    • v.2 no.1
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    • pp.131-150
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    • 1984
  • The purpose of this study is to explore the family as an interaction system, concentrating on the mutual influences between communication and family development; (1) how Communication patterns affect family relationships, and (2) how relationships among family members affect communication. In order to do this Galvin, Brommel used the following frame work; family is a system in which communication regulates cohesion and adaptability by a flow of message patterns through a defined network of evolving interdependent relationships. A family system consists of members, the relationships among them, the family attributes, the members attributes and an environment in which family functions. Within the framework of common cultural communication patterns, each family has the capacity to develop its own communication code based on the experiences of individual members and the collective family experience. Most of us develop our communication skills within the family context learning both the general cultural language and the specific familial communication code. Communication may be viewed as a symbolic, transactional process as the process of creating and sharing meanings. To say that communication is a process implies a continuous interaction of an indefinite large numbers of variables with a concomitant,. continuous change in the values taken by these variables. Finally the process implies change, Family functions include the primary functions of cohesion and adaptability, and supporting functions of family images, themes, boundaries, and biosocial issues. The primary functions reveal concepts integrated family interaction and supporting function, along with those of cohesion and adaptability, give shape to family life. the characteristics of developed relationships of richness, uniqueness efficiency, substitutability, pacing , openness spontaneity, and evaluation are reflected in the verbal and nonverbal behaviors with which family members negotiated a set of common meanings and develop thier own unique message system. The message system is the major element of communication process and influences both the form and the content of thier relationship and in create and share meanings. Family systems need to provide order and predictability for thier members, specifically focusing on communication rules and the networks by which messages are transmitted. Most rules emerge as a result of multiful interactions. There are basic rules and rules about rules, or metarules. Perceiving the rules of family system is very difficult because often family members don't think about the basic rules, much less the metarules. Breaking the rule may result in the creation of a new set because the system may recalibrate itself to accept more variety of behavior. Families develop communication networks to deal with the general issue. Family adaptability may be seen through the degree of flexibility in forming and reforming networks and networks become a vital part of the decision- making process and relate to the power dynamics operating within the family. Networks also play an integral part in maintaining the roles and rules operating with the family system. Thus networks and rules have mutual influence. The family -of -origin issues influence all aspects of family communication and account for many of the communication patterns, rules and networks and the role of the family -of-origin influences as a primary force for communication on behavior of newly forming systems. Each family system develops its own communication meanings. There is not one right way to communicate within a family but may be indefinitly large change of family life and communication behavior. Study on functional family communication helps to gain a better understanding of dynamics of family communication and ability of a new insight into the family.

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On the Street System of Natural Villages in Seogwipo, Jeju (서귀포시 자연취락지의 도시가로망 구성)

  • 전명택;양성기
    • Journal of Environmental Science International
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    • v.11 no.3
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    • pp.139-148
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    • 2002
  • When the natural villages in Jeju province are incorporated into the district of city planning, they are considered to be a small-scale residential districts. Therefore, a garden city should be planned that considers the characteristics of the villages to implement an appropriate street system, to use the area effectively, and to harmonize the villages with the surrounding communities. There have been an especially large number of problems with the street system in the city of Seogwipo, which was notified as the area of natural settlement. This study analyzes the problems inherent in street planning and the present condition of roads whose construction has been postponed for a long time due to several problems including an inappropriately planned street system. Based on the research of various documents, a practical street system has been investigated. Most of the residents in natural settlement units demand use of the continued the existing roads as well as the implementation of an effective street system. They ask for street planning under which the involved construction would take only a short period of time and would result in only minimal damage to their existing properties. Therefore, the street system should be planned so as to preserve the nature-friendly features of natural settlements, their surroundings and tourism resources. Even after streets hwve been planned and their completion you has been established, the plan should be continuously evaluated, analyzed and compared with other alternatives. The street plan should continuously incorporate improvement measures which would satisfy various aspects of the street system including land use, traffic demand, and future population demands. Both the amount of money to be invested and economical efficiency should be considered for street planning since the street system has a great impact on many industries. Unnecessary costs related to excessive road construction should be avoided. The street network plan should also include the complete evaluation of the natural topography as well as the surrounding. Considering these views, the data concerning the current condition of the city and the related investigation play an important role in establishing a street plan. However, the investigation of future construction plans by the city is as of yet at a very early stage. Therefore, there is an urgent need for the investigational study of the current city development plans. The street system for the natural settlement area should be established only after the thorough investigation of all aspects of street planning. In addition, the plan should be flexible enough to consider the characteristics of Jeju.

Efficient Coverage Guided IoT Firmware Fuzzing Technique Using Combined Emulation (복합 에뮬레이션을 이용한 효율적인 커버리지 가이드 IoT 펌웨어 퍼징 기법)

  • Kim, Hyun-Wook;Kim, Ju-Hwan;Yun, Joobeom
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.30 no.5
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    • pp.847-857
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    • 2020
  • As IoT equipment is commercialized, Bluetooth or wireless networks will be built into general living devices such as IP cameras, door locks, cars and TVs. Security for IoT equipment is becoming more important because IoT equipment shares a lot of information through the network and collects personal information and operates the system. In addition, web-based attacks and application attacks currently account for a significant portion of cyber threats, and security experts are analyzing the vulnerabilities of cyber attacks through manual analysis to secure them. However, since it is virtually impossible to analyze vulnerabilities with only manual analysis, researchers studying system security are currently working on automated vulnerability detection systems, and Firm-AFL, published recently in USENIX, proposed a system by conducting a study on fuzzing processing speed and efficiency using a coverage-based fuzzer. However, the existing tools were focused on the fuzzing processing speed of the firmware, and as a result, they did not find any vulnerability in various paths. In this paper, we propose IoTFirmFuzz, which finds more paths, resolves constraints, and discovers more crashes by strengthening the mutation process to find vulnerabilities in various paths not found in existing tools.

The Seamless Handoff Algorithm based on Multicast Group Mechanism among RNs in a PDSN Area (PDSN 영역내의 여러 RN간 멀티캐스트 그룹 메커니즘 기반의 Seamless 핸드오프 알고리즘)

  • Shin, Dong-Jin;Kim, Su-Chang;Lim, Sun-Bae;Oh, Jae-Chun;Song, Byeong-Kwon;Jeong, Tae-Eui
    • The KIPS Transactions:PartC
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    • v.9C no.1
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    • pp.97-106
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    • 2002
  • In 3GPP2 standard, MIP is used and a PDSN performs the function of FA to support macro mobility. When a MS is roaming from a PDSN area to another, the mobility supported is called macro mobility, while it is called micro mobility when a MS is roaming from a RN area to another in a PDSN area. Since a PDSN performs the function of FA in 3GPP2 standard, it is possible to support mobility but its mechanism is actually for supporting macro mobility, not for micro mobility, thus it is weak in processing fast and seamless handoff to support micro mobility. In this paper, we suggest the seamless handoff algorithm barred on multicast group mechanism to support micro mobility. Depending on the moving direction and velocity of a MS, the suggested algorithm constructs a multicast group of RNs on the forecasted MS's moving path, and maximally delays RNs'joining to a multicast group to increase the network efficiency. Moreover, to resolve the buffer overhead problem of the existent multicast scheme, the algorithm suggests that each RN buffers data only after the forecasted handoff time. To prove deadlock freeness and liveness of the algorithm. we use state transition diagrams, a Petri-net modeling and its reachability tree. Then, we evaluate the performance by simulation.

A Study of the image integration of Product in the digital age (디지털 시대의 제품 이미지 통합화 방안에 관한 연구)

  • 김기수;정병로
    • Archives of design research
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    • v.12 no.4
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    • pp.89-98
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    • 1999
  • The application of tool which has grown rapidly by the age was used for the product development, however as today the computer digitalization has been fixed to the necessary process in every factory-made mass production, making the sensitive desire of designer the digitalization through systematic, rational information database building from the planning level of product to the final mass production in such a environment change. It should satisfy a variety of needs of consumer. The enterprise that hopes to get a winner in the present age brought in computer with useful tool to process information efficiently. The computer has displayed much more excellent computation ability than human to come up to their expectation and the growth of electronic technology was possible to make the computer's high-efficiency, economy and integration. No matter what we have a good economy and integration. No matter what we have a good information there is no meaning unless we are able to use it' so we should take it out by the our need. Therefore, this paper observes a future-oriented possibility of computer & Telecommunication in information society, information-oriented design environment and the trends of minimal and integrated computer. We will improve the designer's ability to develop a novel product that have the diversification of them using application, aiming at computer utilization and image identification design strategy of product in the age of network telecommunication.

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Quality Metric with Video Characteristics on Scalable Video Coding (영상 특성을 고려한 스케일러블 비디오 기반 품질 메트릭)

  • Yoo, Ha-Na;Kim, Cheon-Seog;Lee, Ho-Jun;Jin, Sung-Ho;Ro, Yong-Man
    • Journal of Broadcast Engineering
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    • v.13 no.2
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    • pp.179-187
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    • 2008
  • In this paper, we proposed the qualify metric based on SVC and the subjective quality. The proposed quality metric is for a general purpose. It means we can use it for any video sequences regardless of its temporal and spatial characteristics. The Quality of Service(QoS) is one of the important issues in heterogeneous environment which has diverse restrictions such as limited network bandwidth and limited display resolution. Scalable Video Coding(SVC) is the efficient video coding skill in heterogeneous environment. Because SVC can be adapted to various quality bitstreams using three scalabilities(spatial, temporal, and SNR) from one bitstream which has full scalability. To maximize the QoS in this environment, we should consider the subjective quality which is the viewer response. And also we should consider temporal and spatial characteristics of video sequence because the subjective quality is affected by temporal and spatial characteristics of video sequence. To verify the efficiency of the proposed method, we perform subjective assessments. The experimental results show that the proposed method has high correlation with subjective quality. The proposed method can be a decision tool of SVC birstream extraction.

A Study on the Planning Technique of High-rised Housing Estates Applying Smart Green City Concept : Focus on Multi-functional Administrative City 2-1 Neighborhood (스마트 그린시티 개념을 적용한 고층주거단지 계획기법에 관한 연구 : 행정중심복합도시 2-1생활권을 중심으로)

  • Lee, Seo-Jeong;Lee, Eung-Hyun;Oh, Deog-Seong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.5
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    • pp.379-387
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    • 2016
  • The goal of this research is to identify the planning techniques of high-rise housing estates applying a smart green city concept in order to understand the necessity of integrating 'planning & building' planning techniques and 'smart system' planning techniques and to analyze the current status of application. For the research, firstl, the definition of smart green city was established and high-rise housing estates planning was categorized according to a three space hierarchy, seven planning directions and 17 major features through literature review. Second, 28 'planning & building' planning techniques and 'smart system' planning techniques were derived through literature review and FGI analysis. Last, four cases in Multi-functional Administrative City were analyzed for the current status of application of planning techniques. In conclusion, planning techniques in 'Transportation Network', 'Environment-friendly layout planning of housing', 'Revitalization of green transportation', 'Utilization of new & renewable energy', 'Crime prevention and accident reduction', 'Use of high performance, and efficiency facility' main feature were identified as important planning techniques for Smart Green City and its implications were estimated.

A study on vulnerability analysis and incident response methodology based on the penetration test of the power plant's main control systems (발전소 주제어시스템 모의해킹을 통한 취약점 분석 및 침해사고 대응기법 연구)

  • Ko, Ho-Jun;Kim, Huy-Kang
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.24 no.2
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    • pp.295-310
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    • 2014
  • DCS (Distributed Control System), the main control system of power plants, is an automated system for enhancing operational efficiency by monitoring, tuning and real-time operation. DCS is becoming more intelligent and open systems as Information technology are evolving. In addition, there are a large amount of investment to enable proactive facility management, maintenance and risk management through the predictive diagnostics. However, new upcoming weaponized malware, such as Stuxnet designed for disrupting industrial control system(ICS), become new threat to the main control system of the power plant. Even though these systems are not connected with any other outside network. The main control systems used in the power plant usually have been used for more than 10 years. Also, this system requires the extremely high availability (rapid recovery and low failure frequency). Therefore, installing updates including security patches is not easy. Even more, in some cases, installing security updates can break the warranty by the vendor's policy. If DCS is exposed a potential vulnerability, serious concerns are to be expected. In this paper, we conduct the penetration test by using NESSUS, a general-purpose vulnerability scanner under the simulated environment configured with the Ovation version 1.5. From this result, we suggest a log analysis method to detect the security infringement and react the incident effectively.