• Progress in Superconductivity and Cryogenics
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• v.16 no.2
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• pp.42-46
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• 2014

In this study we investigated ac transport current losses in the face to face stack for the anti-parallel current flow, and compared the electromagnetic properties with those of the single SC tape as well as those of the same stack for the parallel current path. The gap between the SC tapes in the stack varied in order to verify the electromagnetic influence of the neighbors when current flows in opposite direction, and the model was implemented in the finite element method program by the commercial software, COMSOL Multiphysics 4.2a. Conclusively speaking, the loss was remarkably decreased for the anti-parallel current case, which is attributed the magnetic flux compensation between the SC layers due to the opposite direction of the current flows. As the gap between SC tapes was increased, the loss mitigation became less effective. Besides, the current density distribution is very flat cross the sample width for the narrower gap case, which is believed to be benefit for the power electric system. These results are all in good agreement with those predicted theoretically for an infinite bifilar stack.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.5
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• pp.951-959
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• 2014

In the past few years, data leakage of information assets has become a prominent issue. According to the National Intelligence Service in South Korea, they found 375 cases of data leakage from 2003 to 2013, especially 49 of cases have been uncovered in 2013 alone. These criminals are increasing as time passes. Thus, it constitutes a reason for establishment and operation of ISMS (Information Security Management System) even for private enterprises. But to be ISMS certified, there are many exposed or unexposed barriers, moreover, sufficient amount of studies has not been conducted on the barriers of ISMS Certification. In this study, we analyse empirically through exploratory factor analysis (EFA) to find the obstacle factors of ISMS Certification. The result shows that there are six obstacle factors in ISMS Certification; Auditing difficulty and period, Consulting firm related, Certification precedence case and consulting qualification, Internal factor, CA reliability and auditing cost, Certification benefit.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.171-174
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• 2006

A large number of service providers in countries all over the world have established GNSS reference station networks in the last years and are using network software today to provide a correction stream to the user as a routine service. In current GNSS network processing, all the geometric related information such as ionospheric free carrier phase ambiguities from all stations and satellites, tropospheric effects, orbit errors, receiver and satellite clock errors are estimated in one centralized Kalman filter. Although this approach provides an optimal solution to the estimation problem, however, the processing time increases cubically with the number of reference stations in the network. Until now one single Personal Computer with Pentium 3.06 GHz CPU can only process data from a network consisting of no more than 50 stations in real time. In order to process data for larger networks in real time and to lower the computational load, a federated filter approach can be considered. The main benefit of this approach is that each local filter runs with reduced number of states and the computation time for the whole system increases only linearly with the number of local sensors, thus significantly reduces the computational load compared to the centralized filter approach. This paper presents the technical aspect and performance analysis of the federated filter approach. Test results show that for a network of 100 reference stations, with the centralized approach, the network processing including ionospheric modeling and network ambiguity fixing needs approximately 60 hours to process 24 hours network data in a 3.06 GHz computer, which means it is impossible to run this network in real time. With the federated filter approach, only less than 1 hour is needed, 66 times faster than the centralized filter approach. The availability and reliability of network processing remain at the same high level.

• KIPS Transactions on Computer and Communication Systems
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• v.1 no.3
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• pp.193-204
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• 2012

This paper specifies a low-cost global mobility management architecture and protocol procedure called LC-$GM^2$, which is based on Proxy Mobile IPv6. In LC-$GM^2$, mobility management is performed by the network entity. The benefit is the elimination of the wireless link data delivery tunnel overhead between a mobile node and the access router. To compare with the well-known Hierarchical Mobile IPv6 mobility management protocol and GPMIP, the location update, packet delivery, and total cost functions generated by a mobile node during its average domain residence time are formulated for each protocol based on Fluid-flow mobility model. Then, the impacts of various system parameters on the cost functions are analyzed. The analytical results indicate that the proposed global mobility management protocol can guarantee lower total costs.

• The Transactions of the Korea Information Processing Society
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• v.7 no.2
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• pp.347-354
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• 2000

This paper presents the efficient mechanisms for concurrency control and writing authority control in collaborative writing system are represented by the tree structures which consist of the logical objects and the content objects connected to the terminal objects of trees. For concurrency control, we adopted the approach to extend the multiple-granularity-locking-scheme. This scheme allows us to lock any objects at each level of the hierarchy. We also defined the locking compatibility table by analysing the operations applicable to any objects at each level of the hierarchy. We finally suggest the extended-multiple-granularity-locking mechanism which uses the locking compatibilility table for deciding to lock an object. This scheme gives the benefit to maximize the possibility of concurrent accessing to the shared objects. In addition, we suggest a mechanism for writing authority control which prohibits the Non-Group users from modifying the shared objects based on the concept of Group/Non-Group The proposed mechanism allows us to protect copyright very reasonably.

• Archives of design research
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• v.17 no.3
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• pp.421-430
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• 2004

The aim of this research is to develop communication model and tools that would help in incorporating user experience into information appliance product development. To do so, this research suggested three major modelling techniques, including user-experience model, design strategy model and experience product model. Using these modelling tools, any members in design teams (investigator and designers) will be able to communicate their own ideas and research results each other at any period of the product development process. Each tools have distinct factors that would help identify elements in the user research stages, idea generation stages and product development stages. To verify the efficiency of these models, the case study was conducted with final year students at their studio class. As a result, the benefit of using these tools were identified as 1) these tools accelerate the communication between user researchers, designers and engineers and 2) evaluation process of the product is much more dearer that before. and 3) various user research techniques can be explored.

• Archives of design research
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• v.17 no.3
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• pp.245-254
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• 2004

In Accordance with the change of design paradigm, the design process has changed into user-centered workflow from designer-centered workflow. Since the purpose of the past research methods is quantitative analysis or the understanding of the present situation, it doesn't fit in practical design that expressed the user's needs. Therefore, the real data about what they see and how they feel will be useful for the user-centered design. This paper's objective is to analyze eye-movement recordings and pupil size of user for mobile interface design. For this objective, it was experimented on that the user's eyegaze data of using a mobile phone by the Eyegaze Interface System, and analyzed three levels of user's task performance. The results provided evaluation of new developed and old existing interface design of mobile phone by the experiment of eye-movement recordings and pupil size. The benefit of results is compliment of the limitation of current usability test through visual characteristics of design and qualitative data of user.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.598-601
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• 2008

The people, who can't deal with urine and feces by themselves because they can't recognize it, deal with urine and feces with help of protector (Or nurse). For the case of urine and feces, disease of ulcerated flesh of hip like unpleasant feeling, pressure sore, humid tetter due to wetness of diaper can be prevented by changing diaper instantly. However, those people can't be possible to express their opinion, so they can't express their opinion on urine and feces or endure sense of shame. So there is a problem which can't check presence of urine and feces instantly. Accordingly, in order to solve this problem, qualitative improvement of nursing service can be generated by developing u-Care product which instantly let know urine and feces to protector (Or nurse) by perceiving automatically, and benefit of welfare on social dependent class like low income old people and solitude old people can be increased by reducing social welfare expense with increment of nursing expense.

• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.195-208
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• 2009

A network design problem (NDP) formulated as a mathematical program is generally used to find an optimum value to minimize or to maximize some objectives such as total travel time, social benefit, or others. NDP has, however, some limits of describing components of travel patterns like activities and trip generation due to its modeling simplicity, and also it has difficulty in including attributes of regional planning. In order to cope with such limits, this paper extends NDP to the urban planning field and proposes a mathematical program which can describe the interactions between urban social activities and transportation planning. Based on this model the authors try to optimize both urban activities and the transportation system. The model developed in this paper is tested to assess its application with a real-size regional transportation network.

• Journal of Society of Preventive Korean Medicine
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• v.23 no.3
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• pp.109-119
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• 2019

Background : Germany is the first country in the world to introduce modern systems of public health insurance, and the country which most widely uses complementary alternative medicine(CAM) in Europe. In early 21^st century, a large evaluation studies were conducted to include acupuncture in health insurance payments, which were eventually decided. Objectives : This study is to investigate and analyze the process of public policy determination on insurance coverage for acupuncture in German health insurance system. Methods : We collected the data and information through the literature search and from the websites of German government departments and health insurance organizations. To obtain contextual information, German experts of health insurance and acupuncture clinical study were interviewed. Results : As use of acupuncture had been growing, German public health insurers wanted to evaluate the validity of acupuncture coverage and sponsored three evaluation projects for clinical effectiveness of acupuncture using randomized clinical trials, systematic reviews, and pragmatic trials from 2001 to 2005. For some pain condition, acupuncture was founded not to be effective than sham acupuncture, but more effective than standard care. The federal joint committee of health insurance decided to cover acupuncture for chronic pain of lumbar spine and chronic pain in at least one knee joint due to gonarthrosis. Conclusions : Considering the controversial subject matter in the process of acupuncture's health insurance coverage in Germany, expanding the benefits of Korean medicine in Korea needs to come up with ways to overcome the difficulties of placebo effect, standardization and lack of literature evidence.