• Wind and Structures
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• v.29 no.1
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• pp.43-53
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• 2019

Vortex-induced vibration of three circular cylinders (each of diameter D) in an equilateral triangular arrangement is investigated using the immersed boundary method. The cylinders, with one placed upstream and the other two side-by-side downstream, are free to vibrate in the cross-flow direction. The cylinder center-to-center spacing L is adopted as L/D = 2.0. Other parameters include the Reynolds number Re = 100, mass ratio $m^*=2.0$, reduced velocity $U_r=2{\sim}15$ and damping ratio ${\zeta}=0$. Cylinder vibration responses are dependent on $U_r$ and classified into five regimes, i.e. Regime I ($U_r{\leq}3.2$), Regime II ($3.2<U_r{\leq}5.0$), Regime III ($5.0<U_r{\leq}6.4$), Regime IV ($6.4<U_r{\leq}9.2$) and Regime V ($U_r>9.2$). Different facets of vibration amplitude, hydrodynamic forces, wake patterns and displacement spectra are extracted and presented in detail for each regime.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.4 no.1
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• pp.9-14
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• 2010

According to graying of population and income enlargement of people, interest about U-Healthcare of new form fusing with IT technology are enlarged. Need a estimation technology and standard of test method for safety and performance considering usage environment of U-Healthcare medical device. In this research, developed the standard of test method for usage environment safety and performance of U-Healthcare medical device referring IEC standards and KS standards.

• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.39-47
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• 2009

Currently, the minimum breadth as a point available for U-turn setup is designated as "over 9m for one way" in the traffic safety facilities practical manuals, and vehicles allowed to make a U-turn are limited to passenger cars. However, as passenger cars have recently become larger and SUVs (Sports Utility Vehicles) are being popularized, they fail to make a U-turn in one attempt. This causes a traffic jam and a problem with traffic safety. This study proposed, compared, and tested the measured values of actual differences in the turning radius of U-turn by actual cars with estimated values by using PC-Crash, a car accident simulation program. Then, the study forecasted the turning radius of U-turns of Korean passenger cars by using PC-Crash, and proposed appropriate breadth for U-turn setup.

• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.343-343
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• 1999

• The Journal of Information Systems
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• v.19 no.4
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• pp.51-63
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• 2010

U-City applies ubiquitous information technologies such as RFID, GPS, USN to various components of city functions and services. The concept of U-City was popularized especially in Korea and currently more than 40 projects have been carrying out all over country. U-City incorporates advanced information communication technologies into ubiquitous information services to provide better quality of life. The purpose of this study is to analyze preferences for the U-City services by surveying experts in U-City developing companies. This study employs Analytic Hierarchy Process which is very useful tool for performing multi-criteria decision making. Total of 28 responses were used in the analysis. The results indicated that the first 7 most preferred items were from transportation and safety area and environment and healthcare area and 4 out of 6 items in transportation and safety area were ranked among them. It implies that respondents consider countering anxiety caused by congested traffic, natural disasters, crimes, etc most important aspect that U-City should deal with. On the other hand, U-Port, U-Convention, U-Logistics, U-Public Administration and U-City Portal were listed as the least preferred services.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.179-186
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• 2017

For more efficient and proactive safety control of imported food, new trend in U.S. is emerging, which assesses the food safety control systems of exporting countries using Systems Recognition Assessment Tool and helps ensure safety of imported foods. This study examines trends in development and application of assessmemnt tool and country assessment reports in U.S. where an active discussion on this issue is in progress. The expert interviews were also conducted. U.S. Systems Recognition Assessment Tool was developed by FDA to recognize the potential value in leveraging the expertise of foreign food safety systems and help ensure safety of imported food. The tool is comprised of ten standards and provides an objective framework for determining the robustness of trading partners' overall food safety systems. Using its own tool, the U.S. FDA conducted a preliminary assessment of the food safety control systems of New Zealand and Canada. According to the U.S.-New Zealand and the U.S.-Canada assessment reports, the overall structure of the systems was similar between the countries. In summarizing the opinions of experts, such a trend in National Food Safety Control System Assessment may be utilized in the sanitary assessment and the control of imported food border inspection frequency before importing food. It would contribute to more effective distribution of national budget and increased public trust. Additionally, international collaboration as well as securing of qualified experts and sufficient budget appear to be crucial to further increase the utility of National Food Safety Control Systems Assessment. In conclusion, firstly, it is critically important for the competent authority of South Korea to proactively respond to international trend in National Food Safety Control System Assessment by identifying the details of its background, assessment purpose, core assessment elements, and assessment procedures. Secondly, it is necessary to identify and complement the weaknesses of Korea's food safety control system by reviewing it with U.S. Systems Recognition Assessment Tool. Thirdly, by adapting the assessment results from imported countries' food safety control systems to the imported food inspection intensity, the resources previously used in inspecting the imported food from accredited countries can be redistributed to inspecting the imported food from unaccredited countries, and it would contribute to more efficient imported food safety control. Fourthly, the competent authority of South Korea should also consider developing its own assessment tool designed to reflect the unique characteristics of its food safety control system and international guidelines.

• Journal of the Korea Safety Management & Science
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• v.12 no.2
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• pp.99-105
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• 2010

In this paper, the uAPSS(u-APartment Service System) that is based on location-aware technology is designed and implemented for a luxury apartment. On the real luxury apartment the developed system has been employed and tested to provide convenient and secure living for residents. It provides services such as emergency call, intelligent elevator operation, and hands-free door access based on the location of the residents with personal device as called smart tag. It can also be applied to other service areas such as the location-aware u-Service for hospitals, high-rising complex buildings, silver towns, etc.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.11a
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• pp.525-526
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• 2018

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.49 no.2
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• pp.55-62
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• 2012

Convergence of information technology (IT) and medical devices enables people to measure health-related information ubiquitously, such as measuring blood glucose at home and checking cardiac signals during exercise and it allows us to access to medical care anywhere and anytime. Nowadays, the market for U-healthcare medical devices is growing rapidly, but guidelines for the evaluation of safety and effectiveness of such devices remain to be formulated. We performed a study on the development of safety and performance evaluation method for portable, hand-held, U-healthcare medical devices. We reviewed current guidelines and standards for home-health devices from the Korea Food and Drug Administration (KFDA) and related international committees such as the ISO/IEEE and CE. We summarized the test methods and items for the evaluation of safety and performance related to U-healthcare medical devices from the above guidelines and standards. We defined requirements for a U-healthcare medical device to demonstrate good performance. In conclusion, we propose an evaluation method for U-healthcare medical devices, which will help improve the safety and reliability of these devices.

• International Journal of Safety
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• v.11 no.2
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• pp.1-4
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• 2012

The falling accidents have increased in the structure and heavy industries. Therefore, a various falling prevention systems with safety block and lanyard have been supplied in order to prevent falling accidents and acquire the long life and cost down for the maintenance. However, there are not the reliable and domestic the falling prevention system until now. Almost systems were imported from U.S.A, Japan, U.K and Germany. The structural safety of the imported safety block is satisfied sufficiently, but it has heavy weight due to the cover with the aluminum and thickness. So, many workers are not feeling themselves. Thus, the aim of this work is to develop a commercial safety block that has a light weight and strength. And the cost efficiency of the system and safety for workers also will be improved remarkably.