• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.3
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• pp.116-124
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• 2011

In this study, a new method to estimate the bridge deflection is developed by using Wireless Tilt Sensor. Most of evaluations of structural integrity, it is very important to measure the geometric profile, which is a major factor representing the global behavior of civil structure, especially bridges. In the past, Because of the lack of appropriate methods to measure the deflection curve of bridges on site, the measurement of deflection had been done restrictly within just a few discrete points along the bridge. Also the measurement point could be limited to locations installed with displacement transducers. So, in this study, the deflection of the structure was measured by wireless tilt sensor instead of LVDT(Linear Variable Differential Transformer). Angle change of tilt sensor shows structural behavior by the change of the resistor values which is presented to voltage. Moreover, the maximum deflection was calculated by changing the deflection angle which was calculated as V(measured voltage) ${\times}$F(factor) to deflection. The experimental tests were carried out to verify the developed deflection estimation techniques. Because the base of tilt measuring is the gravity, uniform measurement is possible independent of a measuring point. Also, measuring values were showed very high accuracy.

• Korean Journal of Materials Research
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• v.22 no.12
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• pp.717-721
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• 2012

Manganese dioxide ($MnO_2$) is one of the most important cathode materials used in both aqueous and non-aqueous batteries. The $MnO_2$ polymorph that is used for lithium primary batteries is synthesized either by electrolytic (EMD-$MnO_2$) or chemical methods (CMD-$MnO_2$). Commonly, electrolytic manganese dioxide (EMD) is used as a cathode mixture material for dry-cell batteries, such as a alkaline batteries, zinc-carbon batteries, rechargeable alkaline batteries, etc. The characteristics of lithium/manganese-dioxide primary cells fabricated with EMD-$MnO_2$ powders as cathode were compared as a function of the parameters of a manufacturing process. The flexible primary cells were prepared with EMD-$MnO_2$, active carbon, and poly vinylidene fluoride (PVDF) binder (10 wt.%) coated on an Al foil substrate. A cathode sheet with micro-porous showed a higher discharge capacity than a cathode sheet compacted by a press process. As the amount of EMD-$MnO_2$ increased, the electrical conductivity decreased and the electrical capacity increased. The cell subjected to heat-treatment at $200^{\circ}C$ for 1 hr showed a high discharge capacity. The flexible primary cell made using the optimum conditions showed a capacity and an average voltage of 220 mAh/g and 2.8 V, respectively, at $437.5{\mu}A$.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.6 s.109
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• pp.574-586
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• 2006

Recently radio communication environment have being standarded by the leading nations against the various technology of communication. Therefore to manage the changing communication environment, research about technology standard and standardization has gone variously in our country. In this dissertation, we discuss the trends of policy and analyze the technical regulation for the extremely low power devices in other countries. In addition, this paper proposes a draft revision of technical regulation for new efficient electric field strength of extremely low power devices in accordance with the technical requirement of Electromagnetic Compatibility. Based on these researches, the contents of this study will be useful to contribute a domestic efficient expansion and development of extremely low power devices and strengthen a competitiveness on international communication markets.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.99-105
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• 2008

For large-scale projects, supply chain management of construction materials is a key to a successful construction project. Inefficient management would cause significant loss in project cost, quality problems (and possible re-work), delayed delivery, claims, etc. On the other hand, efficient supply chain management system can reduce risks even the given project suffers from tricky details and frequent changes thanks to reduced material loss, shortened delivery time, and the quality outcome; this is a win-win situation for both clients and contractors. This paper presents a next-generation intelligent supply chain management system, which is intended to support large-scale construction projects such as urban high-rise buildings, as a strategic vision of the future construction logistics.

• Journal of Korea Port Economic Association
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• v.24 no.1
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• pp.23-39
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• 2008

This paper outlines a plan to promote South Jeonnam region's logistics capability in connection with the regional logistics bases such as Gwangyang Port, Jangseong Integrated Freight Terminal, Mokpo Port and Muan International Airport. The capability of regional innovation bodies, and industrial innovation generally, needs to be improved by establishing a systematic regional innovation plan. Smaller import and export logistics bases, presently scattered in downtown Gwangju and its suburban area, need to be integrated as soon as possible, in advance of the completion of a traffic network connecting all of the triangle logistics bases. Moreover, plans to develop Muan International Airport to the status of a hub airport need to be established, and its function as an air freight terminal should be strengthened. Gwangyang Port and Mokpo Port should be developed as Korea's key harbors with international logistics bases the two ports, presently conducting simple cargo work, should be transformed into general logistics ports conducting logistics, assembling, trading, and international business by developing their surrounding areas.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.4
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• pp.433-442
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• 2010

In this paper, self-calibration algorithm based on covariance matrix is proposed for compensating amplitude/phase mismatch in multi-baseline interferometer direction finding system. The proposed method is a solution to nonlinear constrained minimization problem which dramatically calibrate mismatch error using space sector concept with cost function as defined in this paper. This method, however, has a drawback that requires an estimated initial angle to determine the proper space sector. It is well known that this type of drawback is common in nonlinear optimization problem. Superior calibration capabilities achieved with this approach are illustrated by simulation experiments in comparison with interferometer algorithm for a varitiety of amplitude/phase mismatch error. Furthermore, this approach has been found to provide an exceptional calibration capabilities even in case amplitude and phase mismatch are more than 30 dB and over $5^{\circ}$, respectively, with sector spacing of less than $50^{\circ}$.

• 한국디지털정책학회:학술대회논문집
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• 2005.11a
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• pp.351-364
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• 2005

오늘날은 정보의 홍수라고 표현이 될 만큼 많은 양의 정보를 어디서나 얻을 수 있다. 이러한 많은 양의 정보 중 사람들은 그들이 필요한 정보를 얻기 위하여 인터넷을 사용하며 대부분의 사용자들이 포털 사이트의 검색 서비스를 통하여 그들이 원하는 정보를 검색하고 얻고 있다. 그러나 전통적인 여과 과정을 통해 검증된 인쇄 자원과는 다르게 인터넷상에 있는 자원은 대부분 여과되어 있다고 볼 수 없다. 인터넷상에서 발견되는 정보가 주로 여과되지 않은 상태라는 점을 이해하는 것도 정보를 얻는 사용자 입장에서 매우 중요하다. 그런 의미에서 웹에서는 제공되는 정보에 대한 선정, 조직화, 검색에 대한 표준화가 아직 없기 때문에, 단순히 웹 검색 엔진을 이용한 검색의 결과만을 통해서 원하는 정보를 찾는 것은 쉽 지가 않다(Spink et al, 1999). 비록 원하던 정보를 얻었다 해도 획득한 정보가 신뢰할 만한 것인지를 판단하기가 어렵다. 본 연구에서는 그러한 요구에 부응하기 위해 검색 서비스에 대한 사용자 선호 요인을 선별하고 설문 조사를 통해 검증하고자 한다. 본 연구는 크게 문헌 연구와 실증 연구로 구별되며, 실증 분석에서는 검색 서비스를 사용해 본 경험이 있는 인터넷 사용자를 대상으로 설문을 인터넷 사이트와 설문지를 배부하는 형식으로 진행하여, 통계 패키지를 이용 결과를 분석하였다. 문헌 연구에 따르면 인터넷 사이트를 사용하는데 있어서, 사용자 선호에 영향을 미치는 요인으로 정보 품질, 서비스 연계성, 인지된 유용성, 흥미성, 시스템 품질, UI의 편의성이 있으며 본 연구에서도 이러한 요인을 중심으로 연구 모형을 정하였다. 이러한 요인들에 대하여 가설을 정해 실증 분석을 한 결과, 기본적으로 검색 서비스에 대한 인지된 유용성과 UI의 편의성은 사용자 선호에 영향을 미치는 것으로 나타났다. 반면에 정보 품질, 서비스 연계성, 흥미 성, 시스템 품질은 사용자 선호에 영향을 미치지 못하는 것으로 나타났다. 그러나 정보 품질과 시스템 품질의 결과는 유의 수준에서 크게 넘어가지 않는 결과가 나와 반드시 영향을 미치지 못하는 것은 아니라고 조사되었다. 본 연구는 검색 서비스라는 특정 서비스에 대해서 사용자 선호에 영향을 미치는 요인에 대해서 알아보고자 하였다. 이는 학문적인 측면에서 기존의 통합적인 웹사이트 평가에 대한 연구의 확장을 가능케 하였고, 개인사용자 측면에서는 좀더 좋은 정보를 제공하는 검색 서비스에 대한 이해를 높일 수 있는 계기가 되었다고 할 수 있다.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.3
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• pp.381-387
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• 2011

Measurement controller that acquire and control and observe data from scattering sensors is organic with central control room. Therefore, measurement controller is efficient wireless network than wire network. But, serious problem is happened in security from outside if use wireless network. Therefore, this paper proposed suitable MS-WP cryptographic system to measurement control wireless network to augment network efficiency of measure controller. Result that implement proposed MS-WP cryptographic system by chip level and achieve a simulation, confirmed that 130% processing rate increase and system efficiency are increased double than AES algorithm. Proposed MS-WP cryptographic system augments security and is considered is suitable to measurement controller because that low power is possible and the processing speed is fast.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.6
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• pp.1047-1053
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• 2007

As the acceleration of digital convergence has been deepen and extended to convergence of human, things, and space, the various forms of convergence have been appeared and extended. This paper presents the aim of the system's change which embodies the collaborative electronic government of the application service, which applies the UIT as the changed feature from e-Gov to u-Gov and attains the administrative idea which the u-Gov pursues. It analyzes and applies the propulsive plan of the policies to u-Gov, which is resulted from the variation of the convergence community, and the feature of the UIT, and then it proposed the service model of the new u-Gov with circulation instance adumbration which applies the UIT as the objective realization means of the ultimate administration.

• Journal of Distribution Science
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• v.12 no.6
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• pp.59-65
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• 2014

Purpose - The competitiveness of logistics in the 21st century rests on ensuring the efficiency and effectiveness of its local hub. While considering entry into a niche market in local logistics, it is pertinent to note that Budapest is emerging as a hub in EU enlargement in Eastern Europe. Big, small, and medium-sized businesses in Korea entered Hungary in the early 1990s since then, there has been a significant increase in Korean presence, of approximately 130 times. This study aimed to identify the key distribution issues that have emerged in relation to Eastern Europe. Research design, data, and methodology - This study indicates that 33 major Korean companies were located in Hungary, which serves as an out post to enter the European marketplace. However, Korea's exports to Hungary have declined (-32.0% in 2012) because of a loss of competitiveness against multinational corporations, due to factors such as the rise in current local distribution costs and wages. Hungary, on the other hand, through diversification and expansion of foreign trade with the non-EU markets, including Korea, is increasing its exports. Strategies of emerging countries are compared and reviewed in this study, by examining the vicissitudes of Hungary's distribution methods. Results - There are issues regarding Hungary's innovative ability. Hungary has a history of low wages and high skilled labor. However, the outflow of high-quality human resources for high-wages has become more extensive, and this underlines concerns that the CEE's trade hub is moving to neighboring countries. After the European financial crisis in 2010, the Hungarian economy is now developing, because of the IMF's measures, and it is being transformed into a trade surplus nation, while regaining distribution volumes rapidly. However, if there is continued lack of investment, the supply chain is weakened and exports decline amidst competition with TNCs or with China's distribution networks. Conclusions - It is necessary to create a new logistics approach for increasing trade between Korea and Hungary. First, Korean small and medium enterprises (SMEs) should build trust by working with advanced Hungarian talent, and they should expand into state-of-the-art fields instead of being confined to traditional sectors. Second, this study focuses on limiting and lowering their high expectations for success according to foreign direct investment (FDI) inflows and the role in the CEE distribution hub Korea should try to strengthen the distribution hub with its centralized population, using better, more highly educated human resources, thereby sustaining more innovative ability. Further, the positive effects of these measures are manifested in enhanced business on both sides of Hungary, namely, the EU and non-EU nations such as Turkey and emerging markets around Europe, and a better engagement in the core placement of culture and industry. For this, Korea can contribute to, and benefit from, a Hungarian logistics center, for adopting the high-tech cluster systems and commercializing distribution technology such as RFID·USN.