• Journal of the Korean Geographical Society
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• v.44 no.2
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• pp.187-205
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• 2009

Failures on network components of a public transportation system can give rise to the severe degradation of entire system functionality. This paper aims at exploring how potential failures can affect the system flows and reliability of subway network systems in Metropolitan Seoul. To evaluate the range of impacts of disruptions, this research employs a probabilistic approach, network reliability. Network reliability measures the network resiliency and probability of flow loss under a variety of simulated disruptions of critical network components, transfer stations in subway system. By identifying the best and worst scenarios associated with geographical impact, as well as evaluating the criticality of transfer stations, this research presents some insights for protecting current subways systems.

• Journal of the Korean Operations Research and Management Science Society
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• v.22 no.3
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• pp.23-36
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• 1997

In the design of telecommunication network, the network configuration using hubbing topology is useful for designing and managing the network efficiently : i. e. all of central offices (COs) are grouped into clusters. Each cluster has one hub consisting of large-scale transmission facilities like digital cross-connect systems and ATMs. In clustering process, the community of interest and geographical factor should be considered. However, there exists a tradeoff between two factors. One is to minimize total link costs for geographical factor and the other is to maximize the total intra-cluster traffics for community of interest. Hence, this can be solved by multiobjective linear programming techniques. In this paper, the problem under considerations is formulated as two p-median subproblems taking into considerations total costs and total intra-traffics, respectively. Then we propose the algorithm to solve the problem based on the concept of cost-traffic tradeoff. The algorithm enables to identify efficient cost-traffic tradeoff pairs. An illustration is also presented.

• International Commerce and Information Review
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• v.9 no.1
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• pp.259-274
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• 2007

The paradigm of the global logistics network has been rapidly changing from traditional concept of productivity in cost terms, toward the new characteristics of innovative productivity in terms of economies of scale, economies of scope, and economies of network. As the ship or airplane becomes larger and speedier, the less logistics hub required. The more diverse logistics parties integrate each other horizontally or vertically, the higher synergy effects they get. The more systematic concurrent engineering available for global supply chain management such as Korean manufacturers in China, the higher productivity they get. The paper analyzes these three paradigms of logistics into the application for the Korean manufacturers in China and concludes that the Korean government, the companies in China should be more focused on the governance of the logistics and the intermediary such as the 4th party logistics(4PL) is definitely developed its role and functions based on three paradigms above mentioned.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.8
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• pp.709-716
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• 2005

As a way to build more efficient and intelligent container cranes for todays hub ports, communication networks are used to interconnect numerous sensors, actuators, controllers, and operator switches and consoles that are spatially distributed over a crane. Various signals such as sensor values and operator's commands are digitized and broadcast on the network instead of using separate wiring cables. This not only makes the design and manufacturing of a crane more efficient, but also easier implementation of intelligent control algorithms. This paper presents the performance evaluation of CAN(Controller Area Network), TTP(Time Triggered Protocol) and Byteflight that can be used for cranes. Through discrete event simulation, several important quantitative performance factors such as the probability of a transmission failure, average system delay (data latency) and maximum system delay have been evaluated.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.10
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• pp.4251-4256
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• 2015

Background: Exposure to cigarette may affect human health and increase risk of a wide range of diseases including pulmonary diseases, such as chronic obstructive pulmonary disease (COPD), asthma, lung fibrosis and lung cancer. However, the molecular mechanisms of pathogenesis induced by cigarettes still remain obscure even with extensive studies. With systemic view, we attempted to identify the specific gene modules that might relate to injury caused by cigarette smoke and identify hub genes for potential therapeutic targets or biomarkers from specific gene modules. Materials and Methods: The dataset GSE18344 was downloaded from the Gene Expression Omnibus (GEO) and divided into mouse cigarette smoke exposure and control groups. Subsequently, weighted gene co-expression network analysis (WGCNA) was used to construct a gene co-expression network for each group and detected specific gene modules of cigarette smoke exposure by comparison. Results: A total of ten specific gene modules were identified only in the cigarette smoke exposure group but not in the control group. Seven hub genes were identified as well, including Fip1l1, Anp32a, Acsl4, Evl, Sdc1, Arap3 and Cd52. Conclusions: Specific gene modules may provide better understanding of molecular mechanisms, and hub genes are potential candidates of therapeutic targets that may possible improve development of novel treatment approaches.

• Journal of architectural history
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• v.25 no.2
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• pp.7-19
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• 2016

Shenyang was one of the representative transportation hub of Northeast China during the modern period. The formation and development of the railway network gave great influence on Shenyang's city development. In order to understand the relationship between railway and city development, first, we classified Shenyang's city development period by the railway network's formation and expansion process. Then, we analyzed the relationship between railway and city space by five categories. The results of this study are as follows. First, before railway was constructed, Shenyang was a castle city, which also was the economic center of Northeast China. This was the main reason Shenyang was chosen as a railway zone. During the modern period, the castle structure became an obstacle to city transportation and environment, therefore, it was disposed. During the period of railways' expansion, South Manchuria, Jingfeng and Shenhai railway line was constructed in Shenyang. Since each line had different operation organizations, city sites along the railways were planned separately. However, these operation organizations had one common purpose, which was to use railway as an accelerator for economic development. During the period of railway's military usage, railway was reorganized as military supply transport for the Japanese, which also was used as a tool for the expansion of colonialism. Second, after Shenyang's city space was reconstructed along the railway, it created a close connection with city structure, city facilities, landscape and city transportation system. Hence, the railway system played a key role in modern city planning.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.454-465
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• 2015

This research analyzed characteristics of networks among stakeholders related to forest trail management. Results of analysis showed that Jiri way and Uljin trail had council-led network. As both trails were supported by government, the government had much power to make decisions and manage trail. But parts that mediated differences of interests among various stakeholders were insufficient. To manage forest trails effectively, it is necessary that hub organization which can have networks and make decision considering different interests have to develop and it have to authorize hub organization to take a right role for management of forest trails.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.285-288
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• 2005

Neural networks are known as kinds of intelligent strategies since they have learning capability. There are various their applications from intelligent control fields; however, their applications have limits from the point that the stability of the intelligent control systems is not usually guaranteed. In this paper we propose a neuro-adaptive controller for robot manipulators using the radial basis function network(RBFN) that is a kind of a neural network. Adaptation laws for parameters of the RBFN are developed based on the Lyapunov stability theory to guarantee the stability of the overall control scheme. Filtered tracking errors between the actual outputs and desired outputs are discussed in the sense of the uniformly ultimately boundedness(UUB). Additionally, it is also shown that the parameters of the RBFN are bounded. Experimental results for a SCARA-type robot manipulator show that the proposed neuro-adaptive controller is adaptable to the environment changes and is more robust than the conventional PID controller and the neuro-controller based on the multilayer perceptron.

• The Journal of Information Systems
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• v.18 no.3
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• pp.47-70
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• 2009

Social network is one of the representative analytical method of the complexity theory and this research analyzed various and unique strategic alliance model of e-business domain using social network technique. A lot of small and medium firms of e-business field had developed many useful type of strategic alliances for the firms tried to maximize the effect of advertisement, marketing and to make up for their weak points and to compete with huge company with capital strength long before. But it is too rare to analyze the structure of the firm networks and to study the evolution and extension of business model considered the role of each company in the network. Social network analysis helps each firm's network easily visualized and completely modelized. Additionally, this paper cries to analyze the relationship between the role of hub and broke in the firm networks for strategic alliance, and financial performance. We demonstrate the firm with finer business model to the business environment can make higher financial performance. This implies that the firm that can create new finer business model, will lead the network of e-business firms and evolve the industry of e-business.

• Journal of Navigation and Port Research
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• v.40 no.1
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• pp.43-50
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• 2016

Amid of the logistics hub center competition is going to intensifying between the world major port, it is essential to pre-occupied the base in the logistics hub world take advantage of advanced technology of logistics equipment than other ports. In existing container terminal, when container moves the terminal use the omnidirectional and directional antenna in order to exchange data information on the basis of 802.11 wireless network system. Case of loading height of exceeding, the blind sport will occur and a limited frequency channel can't help using in the area. A limited frequency channel usage and nested areas happen to use the closed terminal, it has a great influence to operate the terminal working. In this paper, LTE network is configured provided by the specified company ('L' Corp,.Ltd) and terminal data extracted through LBO (Local Breakout) in the cell site which is configured directly with container terminal operation server. Using this method, container terminal yard equipment operate without overlapping arises with uninterrupted data presented for ways to efficiently. I would suggest both the existing wireless AP LAN configuration of container terminal and new LTE system and applied to the real yard operating devices situations. Through these methods presented comparative the existing network traffic with new constructed LTE configuration. I admired to suggest that wireless network LTE introduction is fundamental factors to get rid of the blind spot, the problem of limited frequency channel and overlapping arises. These essential points can be a continual improving terminal services and more efficient terminal operational management.