• KIPS Transactions on Computer and Communication Systems
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• v.1 no.1
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• pp.35-46
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• 2012

The development of wireless communication systems has resulted in the availability of several access technologies at any geographic area, such as 3G networks, wireless local area networks (WLANs) and wireless broadband networks. The development of these technologies is provided for users who have experienced mobile network environments which are slow or fast-movement environment and change distance between the AP(Access Point). This paper describes network performance issues in various environmental changes. Also, Fuzzy logic is applied to evaluate the performance in vehicle networks around users' environmental factors to focusing on the minimizing of transfer time and costs. First, WLAN and 3G networks fixed distance between AP, Second, WLAN and 3G networks random distance between APs, finally above two environmental with vehicle Ad hoc networks is analyzed. These V2I and V2V environmental condition are assumed. Results which based on Fuzzy logic suggest an optimal performance in vehicle network environments according to vehicle speed and distance between APs. Proposed algorithm shows 21% and 13% improvement of networks performance in V2I and V2V environment.

• The KIPS Transactions:PartD
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• v.11D no.4
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• pp.783-798
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• 2004

An e-business client application in ubiquitous mobile computing environment may become disconnected from the enterprise server due to broken communication connections caused by the limitation of mobile computing environments(limited battery life of the mobile device, low bandwidth communication, incomplete wireless communication infrastructure, etc). It Is even Possible that mobile client application Intentionally operates in disconnected mode to reduce communication cost and the power consumption of the mobile device. We use “data hoarding” as a means of providing local autonomy to allow transactions to be processed and committed on the mobile host despite of disconnection. The key problem to this approach is the synchronization problem that serialize potentially conflicting updates from disconnected clients on master objects of the server database. In this paper, we present a new transaction synchronizing method that splits a transaction into a set of independent component transactions and give the synchronization priority on each component taking the possibility of use and conflicts in the server into consideration. Synchronization is performed component by component based un synchronization priority. After the Preferred component of a no bile transaction succeeds in synchronization with the server, the mobile transaction can pre-commit at server. A pre-committed transaction's updated value is made visible at server before the final commit of the transaction. The synchronization of the component with low synchronization priority can be delayed in adaption to wireless bandwidth and computing resources. As a result, the availability of important data updated by mobile client is increased and it can maximize the utilization of the limited wireless bandwidth and computing resources.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.15-15
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• 2011

The radar observation system in Japan is operated by two governmental groups: Japan Meteorological Agency (JMA) and the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) of Japan. The JMA radar observation network is comprised of 20 C-band radars (with a wavelength of 5.6 cm), which cover most of the Japan Islands and observe rainfall intensity and distribution. And the MLIT's radar observation system is composed of 26 C-band radars throughout Japan. The observed radar echo from each radar unit is first modified, and then sent to the National Bureau of Synthesis Process within the MLIT. Through several steps for homogenizing observation accuracy, including distance and elevation correction, synthesized rainfall intensity maps for the entire nation of Japan are generated every 5 minutes. The MLIT has recently launched a new radar observation network system designed for flash flood observation and forecasting in small river basins within urban areas. It is called the X-band multi parameter radar network, and is distinguished by its dual polarimetric wave pulses of short length (3cm). Attenuation problems resulting from the short wave length of radar echo are strengthened by polarimetric wavelengths and very dense radar networks. Currently, the network is established within four areas. Each area is observed using 3-4 X-band radars with very fine resolution in spatial (250 m) and temporal (1 minute intervals). This study provides a series of utilization procedures for the new input data into a real-time forecasting system. First of all, the accuracy of the X-band radar observation was determined by comparing its results with the rainfall intensities as observed by ground gauge stations. It was also compared with conventional C-band radar observation. The rainfall information from the new radar network was then provided to a distributed hydrologic model to simulate river discharges. The simulated river discharges were evaluated again using the observed river discharge to estimate the applicability of the new observation network in the context of operations regarding flood forecasting. It was able to determine that the newly equipped X-band polarimetric radar network shows somewhat improved observation accuracy compared to conventional C-band radar observation. However, it has a tendency to underestimate the rainfall, and the accuracy is not always superior to that of the C-band radar. The accuracy evaluation of the X-band radar observation in this study was conducted using only limited rainfall events, and more cases should be examined for developing a broader understanding of the general behavior of the X-band radar and for improving observation accuracy.

• Journal of Korea Port Economic Association
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• v.25 no.3
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• pp.183-206
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• 2009

The purpose of this study is to suggest the new strategies for strengthening the competi tiveness of Incheon port. To measure the calling factors and satisfaction of ports, this study developed a list of 24 items using a seven-point Likert scale through the previous literature reviews, pilot test and emerging factors. Factor analysis, regression analysis, one sample T-test, IPA and SPSS were conducted to verify the determinants choosing ports and customer satisfaction. The result of an empirical study revealed that the cargo volume and information system, etc. in Incheon port was evaluated as satisfied factors and berth availability and port charge, etc. as dissatisfied factors. Based on the outcomes of this study, to strengthen the competitiveness of Incheon port, several strategies were advised such as the inducement of North American and European cargo, port infrastructure, dedicated terminal and GTO inducement, hinterland construction, logistics companies inducement and cooperation with neighboring ports.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.27 no.4
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• pp.76-86
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• 2014

Objective : This study was performed to find out the differential points of the pattern identification for Acne vulgaris and suggest them to the clinic setting Methods : We searched the papers that suggest patterns identification for Acne vulgaris through China National Knowledge Infrastructure(CNKI), Oriental Medicine Advanced Searching Integrated System(OASIS), Korean Traditional Knowledge Portal(KTKP), Korean Studies Information Service System(KISS). We looked through all the papers, excluded unintended papers, and finally chose some papers that are suitable for inclusion. Then, We extracted all the patterns of Acne vulgaris and chose frequently suggested patterns. Finally we extracted symptoms from selected patterns and arranged them in order of frequency. Results and Conclusions : 1. We found 215 papers and chose 17 papers (Korean : 6, Chinese : 11). 2. We extracted total 67 demonstrations and chose Patterns of Wind-Heat, Damp-Heat, Phlegm and Static blood, Disharmony of the Thoroughfare and Controlling vessels. 3. In Acne vulgaris, the pattern of Wind-Heat tends to have a red papule, sometimes pustule, pain with itching, burning sensation, tidal reddening of the cheeks, white head or black head. The pattern of Damp-Heat tends to have a pustule, node, redness and swelling, pain and greasy skin. The pattern of Phlegm and Static blood has a tendency to be a nodule or cystoma that is hard, dark, painful, long lasting and hard to recover and easy to recur with a scar, pimple, pigmentation. The pattern of Disharmony of the Thoroughfare and Controlling vessels tends to be exacerbated before menstruation, have a small papule that is not easily treated under the chin or around the mouth.

• Journal of Convergence for Information Technology
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• v.11 no.9
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• pp.35-42
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• 2021

The purpose of this paper is to review the small unmanned aerial system (sUAS) safety policy promoted by the United States(US) government. Therefore, in this paper, along with sUAS risk factors, the risk factors of sUAS that the US government is interested in are described. In addition, the risk factors were classified into physical and non-physical factors, and provisions mentioned in the Federal Aviation Administration(FAA) Relicensing Act were reviewed. Other risk scenarios were analyzed focusing on target scenario items that the FAA is interested in, such as flight operation disruption, infrastructure damage, and facility trespassing. Of course, we looked at the risk management principles promoted by the US FAA. In this paper, as a research method, the direction and contents of the FAA's sUAS policy were studied and reviewed from the analysis of major foreign journals and policy. In the research result of this paper, by analyzing the FAA sUAS safety risk management policy, the integrated operation and safety policy, physical risk management policy, operation and safety regulation, and sUAS policy and technology direction necessary for establishing the sUAS safety risk management guide in Korea are presented. The contribution of this study is to identify the leading US sUAS safety policy direction, and it can be used as basic data for deriving future domestic policy directions from this. Based on the research results presented in the future, policy studies are needed to derive detailed implementation plans.

• Journal of agricultural medicine and community health
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• v.46 no.4
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• pp.218-229
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• 2021

Objectives: The purpose of this study was to suggest the direction of the Healthy Village project for rural residents in accordance with the prolonged COVID-19 by investigating the digital environment for major health problems, the role of a health leader, necessary projects, and non-face-to-face projects for Healthy Village members in the COVID-19 epidemic. Methods: Telephone interview surveys were conducted with 585 residents from November 30, 2020 to December 21, 2020. Results: Health problems perceived by residents were in the order of concerns about infection (48.5%), depression (32.5%), difficulties in using medical services (9.4%), and lack of exercise (7.7%). The role of the health committee in the COVID-19 situation was "encouraging people to follow quarantine rules" with 91.3%. As a necessary health village project, there was a high demand for the provision of health products and mental health projects. 17.9% said that there is a computer or smart device connected to the Internet in their home, and 42.2% said that there is someone in the village who can easily get help if there is a problem in accessing and using Internet information. 36.9% were able to watch videos, and 22.2% were able to use the Internet through public facilities. Conclusion: In a public health crisis, where the provision of public health and medical services to rural residents is not smooth, it is necessary to manage health and quarantine through health leaders in the village, and it is required to establish a digital environment infrastructure that can conduct community participatory health village projects in a non-face-to-face environment.

• International Journal of Computer Science & Network Security
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• v.21 no.12spc
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• pp.459-462
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• 2021

The article examines the main problems of land market formation in Ukraine. The article is devoted to the study of problems and prospects of land market introduction after the abolition of the ban on alienation. The advantages and disadvantages of lifting the moratorium on the purchase and sale of agricultural land are highlighted. The experience of such European countries as France, Germany, Latvia, Romania and Poland in regulating the market of agricultural lands is analyzed. The historical stages of market formation, features of state policy in this area are considered. The authors found that in these countries the market for agricultural land is well developed and works effectively, which has positive consequences for the economy of these countries. After analyzing the experience, we identified common elements of an effective mechanism for regulating the land market in European countries, which can be implemented in Ukraine. It is emphasized that after the opening of the land market it is necessary to prevent the concentration of a large number of agricultural lands in the hands of one person or close persons and it is necessary to create an effective supervisory body, whose main functions will be supervising sales prevention of speculation in the land market. Emphasis is placed on the need to improve legislation in the field of land, organizational and informational conditions for land reform. The Law of Ukraine "On Amendments to Certain Legislative Acts of Ukraine Concerning the Circulation of Agricultural Land" was analyzed, the adoption of which put an end to the systematic extension of the moratorium on the sale of agricultural land. The positive aspects of such reservations are noted, such as the gradual introduction of the land market, quantitative restrictions, the lower limit of the value equivalent, which can not be less than the normative monetary value. At the same time, the problem is that the lack of an imperative norm on termination of the lease agreement in case of refusal of the lessee to purchase such land at a price not lower than expert assessment, will negatively affect its price formation and actually make the landlord hostage.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.161-168
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• 2021

This paper is a maintenance system for bridge represented by Class 3 and other than by law bridges. Domestic bridge are divided into Class 1 & 2 bridges and Class 3 & other than by law bridges. The number of type 3 and other than by law bridges is very large. But, it is considered to be of relatively low importance compared to Class 1 & 2 Bridge Bridge. So, in this paper is propose a maintenance system and procedure for small & medium-sized bridges. However, because the number of small & medium-sized bridges is large, it is not possible to evaluate the performance of all bridges like Class 1 & 2 bridge. The reason is the lack of manpower and budget. Based on the Risk Matrix method, a maintenance procedure was created to select the bridge for which performance evaluation should be performed first. For this purpose, basic information of the bridge is used. And, the developed maintenance procedures were applied to the bridges in actual use.

• Korean Journal of Construction Engineering and Management
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• v.20 no.2
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• pp.113-118
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• 2019

Recently, the maintenance concept of infrastructure has been changed from the stability management of the structure determined by the safety inspection of the existing facilities to the asset management related to evaluating and managing the performance of the facilities. For management of the property of the facilities, it is necessary to efficiently classify their information for the maintenance and service level of the facilities and to manage them. In the case of power plant facility, especially, it is a complex structure, which is constructed in a various component and detail. In this study, therefore, the components of power plant facility were classified into facilities, spaces, parts, and elements considering the type of integrated construction classification system in Korea. To reflect the deterioration rate of the facility in accordance with environmental conditions such as airborne salt and humidity etc., it was classified by adding direction, interior, and exterior condition of each component not to be considered in the existing classification system for its effective and systematic maintenance, since it is generally located in the coastal area due to the operation of the power generation structure. The classification system developed in this study can be used as fundamental data for development of the computer system for asset management of power plant facility.