• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1996.04a
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• pp.235-239
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• 1996

분류가 모서리에 충돌할 때 발생하는 순음성 소리인 쐐기소리(edgetone)는 공력음향의 대표적인 현상으로서 지금까지 수많은 연구가 있어 왔으며 그 대부분의 특성이 규명되었다고 할 수 있다. 쐐기소리의 발생기구인 되먹임(feedback) 이론을 처음으로 제안한 이는 Powell로서 그는 되먹임사이클의 위상조건에 의하여 주파수특성에 관한 모델을 제안하였으며, 최근 그 모델의 위상인자에 관하여 Kwon은 새로운 값을 제안한 바 있다. 그런데, 쐐기소리의 이론은 주로 분류가 쐐기나 벽에 충돌할 경우에 집중되어 왔으며 분류가 원통에 충돌하여 발생하는 경우에 관한 연구는 Krothapalli의 초음속분류에 관한 연구와 Mochizuki등의 아음속분류에서 원통지름의 영향에 관한 연구를 들 수 있을 뿐이다. Mochizuki등은 원통의 지름이 노즐의 높이보다 작은 경우에 쐐기 소리의 주파수가 원통의 와류이탈(vortex shedding) 주파수와 같은 것을 관찰하였다. 그러나 분류와 원통이 작용하여 발생하는 쐐기소리의 주파수 특성에 관한 이론적 해석을 시도한 연구는 없으며 또한 방사음장의 특성에 관하여도 Han과 Kwon에 의한 모델이 발표된 바 있으나 실험적으로 입증되지 못하였다. 따라서, 본 연구의 목적은 2 fig.1과 같이 2차원 분류가 원통에 충돌할 때 발생하는 쐐기소리의 주파수특성의 정량적인 모델을 세우고 방사음장의 지향특성의 이론 모델을 확립하는 것이다. 먼저 주파수특성을 실험하고 되먹임이론을 적용하여 분석하므로써 유효음원의 위치를 구하고 또한, 수직벽에 작용하여 발생하는 충돌음(impinging tone)의 경우를 실험하여 주파수특성을 비교 고찰하므로써 유효음원의 위치에 관한 이론을 입증한다. 아울러 원통과 평면벽의 각 경우에 방사음장의 지향특성을 측정하고 고찰한다.2,5,6]을 단계별로 고찰하여, 점점 까다로워져 가는 선박 진동규제[3,4]에 대처하고 승무원의 안락성에 대한 욕구, 구조물의 안전성, 장비의 성능보존이 만족되는 저진동 선박의 건조를 위해 향후 해결해야할 과제들을 도출하여 선박진동분야이 연구개발 방향을 제시하고자 한다. 하는 것은 진단의 정밀도에 문제가 있을 것으로 생각된다. 따라서 언어적진리치가 도입되어 [상당히 확실], [확실], [약간 확실] 등의 언어적인 표현을 이용하여 애매성을 표현하게 되었다. 본 논문에서는 간이진단 결과로부터 추출된 애매한 진단결과중에서 가장 가능성이 높은 이상원인을 복수로 선정하고, 여러 종류의 수치화할 수 없는 언어적(linguistic)인 정보ㄷㄹ을 if-then 형식의 퍼지추론으로 종합하는 회전기계의 이상진단을 위한 정밀진단 알고리즘을 제안하고 그 유용성을 검토한다. 존재하여도 모우드 변수들을 항상 정확하게 구할 수 있으며, 또한 알고리즘의 안정성이 보장된 것이다.. 여기서는 실험실 수준의 평 판모델을 제작하고 실제 현장에서 이루어질 수 있는 진동제어 구조물에 대 한 동적실험 및 FRS를 수행하는 과정과 동일하게 따름으로써 실제 발생할 수 있는 오차나 error를 실험실내의 차원에서 파악하여 진동원을 있는 구조 물에 대한 진동제어기술을 보유하고자 한다. 이용한 해마의 부피측정은 해마경화증 환자의 진단에 있어 육안적인 MR 진단이 어려운 제한된 경우에만 실제적 도움을 줄 수 있는 보조적인 방법으로 생각된다.ofile whereas relaxivity at high field is not affected by τS. On the other hand, the change in τV does not affect low field profile but strongly in fluences on both

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.22 no.1
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• pp.47-77
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• 2011

Due to the growth of people's use of the Internet as well as interests in health, people's needs of health information have rapidly increased in public libraries. Nevertheless, there are few studies in Korea about users' needs for health information and services that public libraries can offer to support these user groups. In the current study, a comprehensive literature review was conducted in order to understand the role of public libraries and librarians in serving users with health information and to identify the types of consumer health information(CHI) services available to users in public libraries. As for the CHI services that public libraries can offer for users, the current study emphasizes and discusses the directions and guidelines for improving the following six approaches: 1) CHI collection and information resource building, 2) CHI reference services, 3) CHI user education and training program development, 4) CHI services for minority/disability/cultural diversity groups of users, 5) CHI outreach program development, and 6) CHI network development with medical libraries, academic libraries, hospital, and medical institutions and associations. Although most of the discussion in the current study centers on cases and services provided in the United States or other countries, findings would be used to inform the importance of CHI services in public libraries, and to design and develop CHI services in Korea.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.3
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• pp.401-417
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• 1994

In this paper, a new testable design technique for domino CMOS circuits is proposed to detect stuck-at(s-at), stuck-open(s-op) and stuck-on(s-on) faults in the circuits by observing logic test reponses. The proposed technique adds one pMOS transistor per domino CMOS gate for s-op and s-on faults testing of nMOS transistors and one nMOS transistors and one nMOS transistor per domino gate or multilevel circuit to detect s-on faults in pMOS transistors of inverters in the circuit. The extra transistors enable the proposed testable circuit to operate like a pseudo static nMOS circuit while testing nMOS transistors in domino CMOS circuits. Therefore, the two=phase operation of a precharge phase and a evaluation phase is not needed to keep the domino CMOS circuit from malfunctionong due to circuit delays in the test mode, which reduces the testing time and the complexity of test generation. Most faults of th transistors in the proposed testable domino CMOS circuit can be detected by single test patterns. The use of single test patterns makes the testing of the proposed testable domino CMOS circuit free from path delays, timing skews, chage sharing and glitches. In the proposed design, the testing of the faults which, require test sequences also becomes free from test invalidation. The conventional automatic test pattern generators(ATPG) can be used for generating test patterns to detect faults in the circuits.

• Journal of Distribution Science
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• v.6 no.2
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• pp.5-19
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• 2008

This study aims to provide the present general state of basic data about refrigeration and freezing warehouses scold storages because basic data about refrigeration and freezing warehouses are insufficient and imperfect at the moment. Research contents include the present general state of cold storages such as sales amount, capital(money invested), storage possession state by type, keeping area, cold storage facility capacity, and facility state such as existence of rack, building structure and floor height, and possessed facility state. According to research results, it was found that 86.7% of refrigeration and freezing warehouses are located in the capital region and Busan region in terms of regional distribution, and the average keeping area was found to be bigger in these two regions than that of other regions. In addition, the research shows that more than 80% of companies possess bonded warehouses and there was no big difference in the size and capacity of refrigeration and freezing warehouses. Regarding building structure, most of them were found to be reinforced concrete. However, only 25% of companies installed racks, but there was no statistical significance between existence of rack and the amount of capital and sales. Possessed facilities were found in the order of freight elevator, information system and dock. When it comes to cargo gear, companies were found to possess 9.1 units of forklift and 2.2 units of reach stacker in average. This research is expected to lay a basis for investigating, predicting and developing the local cold storage industry, and more detailed studies will be needed in the future.

• Land and Housing Review
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• v.2 no.3
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• pp.249-258
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• 2011

In order to achieve an efficient urban regeneration of the nation, it is required to determine the extent of decline nation-wide and the declined areas for each district and also to evaluate the potentials of the concerned areas. For this task to be accomplished, a construction of a comprehensive diagnostic system based on spatial information considering diversity and complexity is required. In this study, a total information system architecture for urban regeneration is designed as part of the construction of such a diagnostic system. In order to develop the system, a city and district level unit decline diagnostic indicators has been constructed and a decline diagnostic system has been developed. Also, a scheme to promote the advancement of the system is proposed. The DB construction is based on the city and district level nation-wide and metadata for the concerned level is constructed as well. The system is based on the Open API and designed to be flexible for extension. Also, an RIA-based intuitive UI has been implemented. Main features of the system consist of the management of the indicators, diagnostic analysis (city and district level decline diagnosis), related information, etc. As for methods for the advancement, an information model in consideration of the spation relations of the urban regeneration DB has been designed and application methods of semantic webs. Also, for improvement methods for district unit analytical model, district level analysis models, GIS based spatial analysis platforms and linked utiliation of KOPSS analysis modules are suggested. A use of a total information system for urban regeneration is anticipated to facilitate concerned policy making through the identification of the status of city declines to identify and the understanding of the demands for regeneration.

• Journal of Food Hygiene and Safety
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• v.23 no.4
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• pp.330-337
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• 2008

Betarich carrots were washed at various hypochloric acid(HCA) concentration and steeping time and packed in PE bag keeping at $8^{\circ}C$ for 12 days, in order eventually to examine microbiology, firmness, surface color, whiteness index(WI) and sensory quality. It was found that total bacterial counts at T-II and T-III with the 3 minute steeping were $4.37{\pm}0.19\;\log\;CFU/g$ and $4.27{\pm}0.13\;\log\;CFU/g$ respectively, showing slight decrease compared to control condition. E. coli was not detected at all treatments but less coliforms were detected at the 8-day treatments of T-II and T-III. Treatment of 3-minute steeping showed smaller reduction in firmness than that of I-minute steeping at 12-days, and T-1 (T-3) had the largest (smallest) reduction among them. It was also found that during the treatment the L-value showed decreasing trend, but the parameter a- and b-value showed increasing trend. WI increased, and its change was small with the increase in HCA concentration. The sensory quality check after 8 day storage showed that evaluation of the off-flavor appeared to be significantly high (p<0.05) at both non-treatment and HCA treatment. On the basis of the results above, it is likely to be more effective to prolong the period of circulation of beta rich carrots if you use HCA over 50 ppm for washing betarich carrots. This study will contribute to improve safety and quality in circulation of beta rich carrots.

• Journal of Food Hygiene and Safety
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• v.33 no.3
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• pp.162-167
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• 2018

The objective of this study was to find out a nomenclature and a code number for fruit commodities from the Codex Alimentarius Commission (Codex) corresponding with a commodity name used in South Korea. In addition, nomenclature or classification for commodity that needs an alteration or detailed examination domestically was determined. In this study, 'Food Code (Korean and English version)' and 'Pesticide MRLs in Food' from the Ministry of Food and Drug Safety and 'Codex Classification of Foods and Animal Feeds' were used. As results, regarding a nomenclature or classification used in South Korea, it appeared that alteration or further examination was needed for the following (English name of commodity, coming from an English version of Food Code). First, reconsiderations for classification of Chinese matrimony vine, fig, five-flavor magnolia vine, and pomegranate are needed as they are classified differently between Korea and Codex. Second, in any case of Korean or English language, nomenclature of commodity is different even within Korea or when it is compared with Codex. Such commodities are: Asian citron, Chinese bush cherry, Chinese matrimony vine, coconut, crimson glory vine, date palm, five-flavor magnolia vine, five-leaf chocolate vine, Japanese apricot, Japanese cornelian cherry, jujube, kiwifruit (golden kiwi), Korean black berry, Korean raspberry, kumquat, lychee, mandarin, persimmon, plum, quince, raspberry, and trifoliate orange. Third, reconsiderations for peach and raspberry nomenclatures are needed as it is currently unclear whether 'peach' includes nectarine and an English nomenclature, 'raspberry', is used in Korea for both various varieties (red, black) and one specific variety.

• Journal of the Korean Society for Library and Information Science
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• v.45 no.2
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• pp.415-437
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• 2011

The increased interest in consumer health information(CHI) has brought about a rapid increase in CHI resources. There are diverse means for obtaining such information, and one CHI acquisition route is the public library. In the U.S. public libraries, the demand for CHI reference services is increasing, and a variety of projects to promote these services are in progress. On the other hand, Korean public library services for CHI is at a very basic level, and thus a very small amount of such research could be found. This study drew suggestions from a literature review of research studies in the U.S. and Canada, and analyzed public library CHI services in Korea. The findings are as follows. 1) Only 17.25% of public libraries in Korea provided CHI service, and it evidences very low needs and awareness for CHI services in Korea. 2) Only three kinds of services including CHI-related websites, users training, and promotional and marketing were provided, and only 13(1.74%) of libraries surveyed offered more than two kinds of services. 3) There were no CHI librarians, nor did any librarians receive CHI-related education. 4) ILL services, outreach services, and cooperation with CHI- and medical-related institutions for CHI services were not found. Therefore, this study suggests that more research on delivery strategies for CHI services should be conducted in the future.

• Journal of Korea Water Resources Association
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• v.46 no.4
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• pp.345-359
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• 2013

In order to manage water quality efficiently and systematically through TMDL (Total Maximum Daily Load), the demand for the construction of spatial data for stream networks has increased for use with GIS-based water quality modeling, data management and spatial analysis. The objective of this study was to present an improved KRF (Korean Reach File) design as framework data for domestic stream networks to be used for various purposes in relation to the TMDL. In order to achieve this goal, the US EPA's RF (River Reach File) was initially reviewed. The improved design of the graphic and attribute data for the KRF based on the design of the EPA's RF was presented. To verify the results, the KRF was created for the Han River Basin. In total, 2,047 stream reaches were divided and the relevant nodes were generated at 2,048 points in the study area. The unique identifiers for each spatial object were input into the KRF without redundancy. This approach can serve as a means of linking the KRF with related database. Also, the enhanced topological information was included as attributes of the KRF. Therefore, the KRF can be used in conjunction with various types of network analysis. The utilization of KRF for water quality modeling, data management and spatial analysis as they pertain to the applicability of the TMDL should be conducted.

• Clean Technology
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• v.18 no.1
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• pp.1-13
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• 2012

Starting with textile products in the middle of 1990, environmental requirements on prohibition of hazardous substances in products have been led by EU member countries and expanded to electrical and electronic equipment with implementaion of RoHS (Restriction of the use of certain hazardous substances in electrical and electronic equipment) in 2006. Under EU REACH (Registration, Evaluation and Authorization of CHemicals), the concept of SVHC (Substances of Very High Concern) and resulting regulatory duties regarding it have been introduced to the supply chain of almost all industry sectors. In this technical review, kinds of hazardous substances, reasons for restrictions and related directives and regulations are reviewed with its influence on the international market. Suggestions are made how to cope with environmental regulations as well as mid-to-long term market strategy to secure global market competitiveness.