• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.6
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• pp.130-137
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• 2010

Due to test facility and specialty, it is physically difficult to conduct the modal tests of large-sized structures such as truck, bus and airplane. So, in case of a large-sized truck, the mode analysis on a full vehicle model comprised of reliable cabin, frame, and deck has been generally performed. However, the reliability of overall vibrational characteristics of the analytic model has not been fairly guaranteed by the testified models of each subsystem owing to the existence of cab suspension and the nonlinear mounting between a chassis frame and a special deck system. In this paper, a method to find out the modal characteristics of a large-sized military truck is presented. New modal test equipment is developed to set the boundary conditions of three military truck variants as close as a free-free condition. And the mode analysis method using coupled structure and dynamic models is established to consider the above-mentioned dynamic non-linearities of the vehicle itself. The usefulness of the suggested method is verified by comparing with the modal test results. Finally, the modal parameters of the final variant are extracted using the proved analytic method.

• The Journal of Korean Medicine
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• v.17 no.2 s.32
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• pp.17-33
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• 1996

Chinese medical science with long history has experience and theory of cure and prevention as well as the perfect different system with western medicine. Western medical science also was introduced in recent times and has been used in fast development in China extensively. Therefore only China that coexist oriental and western medicine is used the term, the integration of oriental and western medicine. Its object is to make better treatment and prevention value with utilizing their strong point and weak point. That is, its great principle is to develop through interchange together without interference in the other science. For mutual growth of both medical science, national concern and support, medical staffs, administrative system and a lot of fruits, etc should be arranged simultaneously. This paper was obtained the as follows. 1. The system of public health administration is composed a sanitary department for a western medicine and a managing agency for a chinese one in the center. There are each local organization under the control both agency in the locality 2. The importance of the integration of chinese and western medicine is to get the merit of special chinese system through the interchange of both medicine and union with modem science and chinese pharmacy. 3. It is the long term and great project. So its important study field is illness treatment and cure, oriental medical remedy and theory, acupuncture and moxibution etc. 4. It makes steady progress in all the healthy medical field. It has studied its foundation, the education of medical staffs, scientific study and strengthening of skill management considerably. 5. The products are the development of new chinese medicines and many researches about traditional chinese medical science. In brief, the integration of chinese and western medical science is the historical stream. Besides it will contribute toward the cure and prevention of human illness for future 21 century.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.12
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• pp.994-1001
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• 2013

Process of helicopter development is divided in design, manufacture and test & evaluation phase. Test & evaluation is performed step by step in order of component test, rig test, system ground test and flight test. After completing ground test and before first flight, US military specification requires 50hrs-PFAT in order to assure flight safety. PFAT is the test which requires tie-down and severe load imposition and it needs special ground test vehicle which is similar to helicopter prototype as well as much cost and period. In case of KUH, we have performed tailored PFAT considering KUH development environment. In this paper, we propose a proper way to perform the PFAT in accordance with development environment by giving KHU PFAT procedure and result.

• Journal of the Korean Institute of Gas
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• v.20 no.1
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• pp.29-39
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• 2016

Electrical apparatuses for use in the presence of explosive gas atmospheres have to be special designed to prevent them from igniting the explosive gas. Flameproof design implies that electrical components producing electrical sparks are contained in enclosures and withstand the maximum pressure of internal gas or vapours. In addition, any gaps in the enclosure wall have to designed in such a way that they will not transmit a gas explosion inside the enclosure to an explosive gas or vapours atmosphere outside it. In this study, we explained some of the most important physical mechanism of Maximum Experimental Safe Gap(MESG) that the jet of combustion products ejected through the flame gap to the external surroundings do not have an energy and temperature large enough to initiate an ignition of external gas or vapours. We measured the MESG and maximum explosion pressure of propane and acetylene by the test method and procedure of IEC 60079-20-1:2010.When the minimum MESG is measured, the concentration of propane, acetylene in the air is higher than the stoichiometric point and their explosion pressure is the highest value.

• Safety and Health at Work
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• v.1 no.1
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• pp.29-36
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• 2010

This article describes a systematic roadmap master plan for advanced industrial safety and health policy in Korea, with an emphasis on. Since Korean industries had first emergence of industrial safety and health policy in 1953, enormous efforts have been made on upgrading the relevant laws in order to reflect real situation of industrial work environment in accordance with rapid changes of Korean and global business over three decades. Nevertheless, current policy has major defects; too much techniques-based articles, diverged contents in less organization, combined enforcement and punishments and finally enforcing regulations full of commands and control. These deficiencies have make it difficult to accommodate changes of social, industrial and employment environment in customized fashion. The approach to the solution must be generic at the level of paradigm-shift rather than local modifications and enhancement. The basic idea is to establish a new system integrated with a risk assessment scheme, which encourages employers to apply to their work environment under comprehensive responsibility. The risk assessment scheme is designed to enable to inspect employers' compliances afterwards. A project comprises four yearly phases based on applying zones; initially designating and operating a specified risk zone, gradually expanding the special zones during a period of 3 years (2010-2012) and the final zone expanded to entire nation. In each phase, the intermediate version of the system is updated through a process of precise and unbiased validation in terms of its operability, feasibility and sustainability with building relevant infrastructures as needed.

• The Korean Journal of Archival Studies
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• no.13
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• pp.233-285
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• 2006

The Study overviews the development process throughout the foundation procedure of the records centres of the urban Construction. The other purpose of the study is to look over the managing process of urban construction records in the Shanghai Municipal Urnan Construction Archives. As the late of 1950s in China, the principle was set up as the special work in every stage of the urban construction, differently general public records. so records centres is established at the agency where is in charge of the records of urban-construction that has managed the records of the urban-construction intensively and unitarily. During the Great Culture Revolution, while Records Management has ceased. after Revolution, Records management for urban construction developed unprecedentedly. As the 1980s in China, urban construction archives instead of records centres existing started to manage records of urban construction. urban construction archives was established at the 332 of 467 urban the whole country in the 1990s. Shanghai Municipal Urban Construction Archives founded in 1987 where has preserved urban construction records of 230,000 files by abiding by the Provisional Regulation of Management of Urban Construction Archives in Shanghai and other regulations. recently urban construction records management looks forward to new aspect. at first, Managing system setting up for affordable new environment (market economy, modernization of information disclosure)is core stage. second, developing the contents as well as managing records is important. finally making a profit is priority for records management.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.95-104
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• 2021

This study was conducted for the purpose of convergence reconstruction of the transition education model for students with disabilities in Korea. Ultimately, this study was also conducted with the aim of enhancing the perspective of the development of a lifelong education support system for the disabled in connection with schools and communities. The research method consisted of a procedure with a meeting of experts based on the procedure of analyzing the previous research literature that tried to materialize the transition education model for students with disabilities from the viewpoint of connection between school age and adulthood. The contents of this study were reflected in the dimension of ensuring consistent connectivity validity based on the viewpoint of school-centered, community-centered, education, and welfare between special education and lifelong education for the disabled in order to reconstruct the conversion transition education model constructed in the current special education field. Accordingly, the transition education model for students with disabilities built in the field of special education centered on school age minimizes the tendency of a fragmented approach between school age and adulthood, and presents a standard basis and structure that can be linked to the entire adulthood. The transition education model was reconstructed convergence in terms of content.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.7
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• pp.4828-4834
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• 2015

From the moment that a firing pin triggers the detonator to the moment that a grenade leaves a barrel is called Action Time. Since a loading and percussion of 40mm grenade happens simultaneously, action time should be within a certain time in order to prevent a Jamming malfunction. Previously, unreliable action time device of 40mm grenade made it difficult to improve quality assurance of K4 Grenade Machine Gun. Here, various sensors were compared and a special device was designed to seek an accurate measurement on action time. In this device, the gap between a signal from an optical sensor in Firing Pin and that from Eddy current probe in the barrel was recorded and data were sent to a computer in real time. Confirming if action time is within the criteria, it is expected that action time plays an important role in quality assurance on 40mm grenade.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.44-52
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• 2017

In this paper, we propose a DFD (Digital Frequency Discriminator) design that has better frequency discrimination and a smaller size. Electronic warfare equipment can analyze different types of radar signal such as those based on Frequency, Pulse Width, Time Of Arrival, Pulse Amplitude, Angle Of Arrival and Modulation On Pulse. In order for electronic warfare equipment to analyze radar signals with a narrow pulse width (less than 100ns), they need to have a special receiver structure called IFM (Instantaneous Frequency Measurement). The DFD (Digital Frequency Discriminator) is usually used for the IFM. Because the existing DFDs are composed of separate circuit devices, they are bulky, heavy, and expensive. To remedy these shortcomings, we use a three delay line ($1{\lambda}$, $4{\lambda}$, $16{\lambda}$) in the DFD, instead of the four delay line ($1{\lambda}$, $4{\lambda}$, $16{\lambda}$, $64{\lambda}$) generally used in the existing DFDs, and apply the microwave integrated circuit method. To enhance the frequency discrimination, we detect the pulse amplitude and perform temperature correction. The proposed DFD has a frequency discrimination error of less than 1.5MHz, affording it better performance than imported DFDs.

• Journal of Preventive Medicine and Public Health
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• v.35 no.1
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• pp.49-56
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• 2002

Objectives : To identify the relationship between the use of medical services by workers with three types of respiratory diseases(total respiratory diseases, acute upper respiratory infections and chronic lower respiratory diseases) and exposure to hazardous agents after controlling for other factors affecting medical services use, such as characteristics of the enterprises(scale, industry type) and employee demographics (sex, age). Methods : The study population comprised 28,882 workers who had undergone general or special medical examinations at the industrial health center at least once between Jan 1995 and Dec 1997 and had possessed medical insurance during the period. We combined medical examination data with medical insurance data in order to analyze the relationship between exposure to hazardous agents and respiratory diseases, Results : Among the 28,882 study subjects, 17,454 employees(60.4%) used medical services more than once during 3-year study period, owing to more than one kind of respiratory diseases. In logistic regression analysis, sex, age and the size of the enterprises proved to be significant variables on the use of medical services for all three types of respiratory disease; The use of medical services increased with employee age. Women used more medical services than men and the employees in the large-scale enterprises used more services than employees in small-scale enterprises. However, exposure to dust or organic solvents did not affect medical service use due to total respiratory diseases or acute upper respiratory infections. Only in the case of chronic lower respiratory diseases did workers exposed to dusts(OR=1.12, 95% CI=1.01-1.24) or organic solvents(OR=1.19, 95% CI=1.05-1.35) use more medical services than those not exposed. Conclusions : Workers exposed to dusts or organic solvents are particularly apt to suffer from chronic lower respiratory diseases and use medical services more often than those not exposed. That is, chronic exposure to hazardous agents such as dusts and organic solvents is believed to be harmful and to cause respiratory symptoms and diseases.