• 한국안전학회지
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• 제32권5호
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• pp.168-178
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• 2017

In order to prevent major and chemical accidents, some of the plants which would like to install and operate hazard chemicals handling facilities must submit Off-site Consequence Analysis due to recent arisen leak accidents since 2015. A lot of chemical industrials choose gas detectors as mitigation equipment to early detect gas vapor. The way of placement of gas detectors has two methods; Code-based Design(CBD) and Performance-based Design. The CBD has principles for gas detectors to be installed with consideration for the place that is expected to accumulate gas, and the leak locations according to legal standards and technical guidelines, and has a possibility to be unable to detect by these rules to locate gas detectors by vapor density information. The PBD has two methods; a Geographic Method and Scenario based Method. The Scenario-based Method has been suggested to make up for the Geographic Coverage Method. This Scenario-based Method draw the best optimum placement of gas detectors by considering leak locations, leak speed information, leak directions and etc. However, the domestic placement guidelines just refers to the CBD. Therefore, this study is to compare existing placement location of gas detectors by the domestic CBD with placement locations, coverages and the number of gas detectors in accordance with the Scenario-based Method. Also this study has measures for early detecting interest of Vapor Cloud and suitable placement of gas detectors to prevent chemical accidents. The Phast software was selected to simulate vapor cloud dispersion to predict the consequence. There are two cases; an accident hole size of leak(8 mm) from API which is the highst accident hole size less than 24.5 mm, and a normal leak hole size from KOSHA Guide (1.8 mm). Detect3D was also selected to locate gas detectors efficiently and compare CBD results and PBD results. Currently, domestic methods of gas detectors do not consider any risk, but just depend on domestic code methods which lead to placement of gas detectors not to make personnels recognize tolerable or intolerable risks. The results of the Scenario-based Method, however, analyze the leak estimated range by simulating leak dispersion, and then it is able to tell tolerable risks. Thus it is considered that individuals will be able to place gas detectors reasonably by making objectives and roles flexibly according to situations in a specific plant.

• Asian-Australasian Journal of Animal Sciences
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• 제30권11호
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• pp.1643-1650
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• 2017

Objective: The control of psychrotrophic bacteria causing milk spoilage and illness due to toxic compounds is an important issue in the dairy industry. In South Korea, Gangwon-do province is one of the coldest terrains in which eighty percent of the area is mountainous regions, and mainly plays an important role in the agriculture and dairy industries. The purposes of this study were to analyze the indigenous microbiota of raw milk in Gangwon-do and accurately investigate a putative microbial group causing deterioration in milk quality. Methods: We collected raw milk from the bulk tank of 18 dairy farms in the Hoengseong and Pyeongchang regions of Gangwon-do. Milk components were analyzed and the number of viable bacteria was confirmed. The V3 and V4 regions of 16S rRNA gene were amplified and sequenced on an Illumina Miseq platform. Sequences were then assigned to operational taxonomic units, followed by the selection of representative sequences using the QIIME software package. Results: The milk samples from Pyeongchang were higher in fat, protein, lactose, total solid, and solid non-fat, and bacterial cell counts were observed only for the Hoengseong samples. The phylum Proteobacteria was detected most frequently in both the Hoengseong and Pyeongchang samples, followed by the phyla Firmicutes and Actinobacteria. Notably, Corynebacterium, Pediococcus, Macrococcus, and Acinetobacter were significantly different from two regions. Conclusion: Although the predominant phylum in raw milk is same, the abundances of major genera in milk samples were different between Hoengseong and Pyeongchang. We assumed that these differences are caused by regional dissimilar farming environments such as soil, forage, and dairy farming equipment so that the quality of milk raw milk from Pyeongchang is higher than that of Hoengseong. These results could provide the crucial information for identifying the microbiota in raw milk of South Korea.

• 한국생활과학회지
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• 제18권4호
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• pp.841-855
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• 2009

The main objective of this study is to examine the situations of group-homes for the elderly and clarify the problems of them. This study investigates the present conditions of welfare facilities and supply conditions. 4 group-homes were surveyed in Jeonju and Kwangju cities. Data was collected through various ways including the survey conducted by facility operators, the measurement of living space, and photo-takings. The major results of this study are as follows: 1) With the introduction of nursing care insurance in 2008, the increase of the demand and supply to group-home will be expected, due to less cost for recuperation. The care of elderly in homelike atmosphere is effective to the elderly suffering from dementia. Therefore, it is proper that the supply of group-homes for dementia will be needed. 2) Group-homes for the elderly are being supplied under the standards of welfare facilities in the present. Separate supply standards, however, are needed because they are not suitable for small scale group-homes. 3) To supply Group-homes for the elderly on a one-unit basis would cause various problems such as economical unreality, personnel distribution and so on. It is necessary to supply more than two units for more efficient management. 4) The management of group-homes for the elderly is financially unstable because the operating funds heavily depend on the users or people who are connected with the facilities through private networks. Therefore, additional support is needed to settle the financial problem. It would be helpful to build the public networking that provides information about the group-home for the elderly for the public. 5) In case of the increase in the supply of the group-home in a residential area, it could be helpful to promote the group-home to the public. 6) The operators state that the main problems of group homes for the elderly lie in financial difficulties and the shortage of professionals and volunteers. The financial, personnel, and material support for personnel and the supervision of management are required for the transparency and effectiveness of the facility management. In addition, the closer network and cooperation system with the community is required. 7) The present living environments for group-homes for the elderly leave much room for improvement, considering the physical condition of the elderly. The more careful selections in the color, shape, material, and equipment of the facilities should be made for the convenience of the elderly users.

• 한국정보통신학회논문지
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• 제21권10호
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• pp.1840-1848
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• 2017

선형 무선 센서 네트워크는 일반적으로 순차적 1:1 매핑을 통해 토폴로지가 구성되므로 네트워크의 신뢰성이 우수하여 국경감시, 철도선로 감시 등의 국가 주요 기반 시설 감시에 사용되고 있다. 이러한 선형 무선 센서 네트워크의 구성 요소인 센서노드의 위치를 식별하기 위한 기술들은 주로 GPS 활용 기법과 AOA 및 RSSI 활용 기법들이 제안되었다. 그러나 GPS나 AOA를 이용하는 것은 노드 크기 및 제작비용에 영향을 미치므로 실용적인 센서 네트워크 구축이 쉽지 않고, RSSI 등은 전파환경과 장비의 특성에 따라 위치 식별도의 편차가 커지므로 오류 보정 알고리즘이 복잡해지는 단점이 있다. 본 논문에서는 센서노드들의 메시지 송신 및 수신에 대한 시각소인에 기반한 계층적 거리측정 기법을 제안한다. 제안된 기법은 GPS, AOA, 그리고 RSSI 등을 활용하지 않고 노드간의 측정된 거리를 이용하여 그들의 위치를 식별할 수 있다. 노드간의 거리측정을 위해 수행되는 5개의 알고리즘은 300 MHz 이상의 수정 진동자인 경우에 최대 1m 이내의 오차 범위에서 거리측정이 가능할 것으로 기대된다.

• 한국건설관리학회논문집
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• 제16권3호
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• pp.68-77
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• 2015

최근 초고층 건축물의 증가로 그에 따른 양중계획 및 양중장비의 효율적 관리에 대한 관심이 증대되고 있다. 건설 현장에서 폭넓게 사용되고 있는 전동 호이스트, 크레인 등과 관련된 재해사고가 빈번히 발생하고 있다. 특히 건설용 리프트는 안전 측면에서 정기점검이나 고장에 대비하는 것이 대단히 중요하나 사용시간에 따른 일률적인 정기검사를 수행하고 있는 실정이다. 리프트는 개별 부품의 사용시간 및 부하조건 등에 따라 그 수명이 달라질 수 있기 때문에 실효성이 매우 떨어지는 유지관리 방법이라고 할 수 있다. 본 연구에서는 이러한 문제점을 개선하고 사용자 편의성과 안전성을 증대시키기 위한 방안으로써 센싱 기술을 활용하여 리프트의 실제 사용시간을 측정하고 그에 따른 고장데이터를 분석하여 리프트의 주요 부품들에 대한 개별 점검주기를 산출하는 것을 목적으로 하였다. 연구의 결과물로 리프트의 주요 부품에 대한 점검주기를 산출하고, 리프트 실 사용시간 40시간, 90시간, 130시간, 400시간으로 나누어 그에 따른 점검 부품들을 구분하여 표로 작성하였다. 이를 통해 안전사고를 미연에 방지하고 작업자의 안전성을 향상시켜 효율적인 유지관리 방안을 제시할 수 있을 것으로 사료된다. 또한 리프트 고장으로 인한 공기지연 요소를 사전에 제거하여 공사의 생산성을 증대시킬 수 있을 것이다.

• Journal of East Asia Management
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• 제1권1호
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• pp.29-49
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• 2020

In an intensively competitive global market, small-and medium-sized firms are puzzled about how to develop sustainable competitive advantages against global rivalries, thus leading satisfactory economic performance. However, despite the roles and contributions of such small-and medium-sized firms in the local community and national economies in Japan, little guidance has been offered to the practical issues related to their strategic behaviors toward global management. To fill this notable knowledge gap, this study aims to investigate the conditions in which how Japanese small-and medium-sized could dominates global market, which is one of key challenges in the literature of small business and entrepreneurship. To obtain better insights to this research area, this study undertakes an in-depth interview survey with I.S.T (Industrial Summit Technology) Corporation that shows off the highest global market share (40 per cent) with seamless polyimide tube product widely used in office automation equipment (e.g., copiers and printers). This method of survey is designed to deeply understand historical considerations about how I.S.T Corporation could dominate in the global market of such seamless polyimide tube product. Based on findings drawn from an interview, this study identifies five major factors enabling I.S.T Corporation to be a competitive global hidden company: vision sharing through founder's entrepreneurship, core competence, strategic network, risk management, and employee engagement. Specifically, to become a global hidden champion, sharing the vision motivating employees to partake in shaping company's future will be the first step on the road to global success through founder's entrepreneurship. However, in order to achieve such a vision, the importance of company's core competence cannot be overemphasized, which differentiates your customer solution with those of competitors. As such, a group of experts will be naturally formed and demonstrates your expertise in the global market, thereby building sustainable competitiveness. On the other hand, to maintain sustainable competitiveness, it is necessary to make up for the weaknesses small-and medium-sized firms suffer from competitive resources while strengthening their own strengths through strategic networks with external organizations. Here, every company has to understand the critical role of risk management, which is essential in this process of being global company so as not to lose your own strengths. Last but not least, do not forget the significant effects of employee engagement in firm performance. To enhance employees' engagement, a company has to create an ideal organization culture which fits into company's history and personality. In doing so, such organization culture can allow the vision and strategy to be implemented into detailed business tactics while facilitating employees to challenge the status quo by experimenting with creative ideas.

• 화약ㆍ발파
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• 제22권3호
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• pp.57-64
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• 2004

국내에서 적용되는 수중발파는 교량의 기초를 위한 수중 우물통 발파와 항만의 수로 증심 또는 준설을 위하여 적용되고 있다 그 중 교각의 기초를 위한 우물통 발파는 우물통내 물을 인위적으로 배수시켜 건조한 상태에서의 천공과 장약을 실시한 후 물을 다시 채운 후 수중에서의 발파를 수행하고 있어 전체적인 작업이 일반 노천발파와 동일하다 할 수 있다. 그러나 항만의 수로 증심과 준설을 위한 수중 발파는 수중 천공이 가능하도록 고안된 바지선을 이용하여 수중에서 천공과 장약 발파 작업이 이루어지는 특수성을 가지고 있다. 따라서 일반 터널이나 벤치발파와는 다르게 장약의 방법과 결선의 방법에 주의를 기울이지 않으면 수압에 의한 사압 등 어려운 조건하에서 불발이 야기될 수 있다. 본 사례연구는 국내 부산항 증심 준설공사에서 수중발파의 특수성을 고려하여 다이너마이트 (메가마이트 I)를 이용한 수중 발파의 장약량 선정과 파이프를 이용한 장약의 방법, 그리고 TLD를 이용한 기폭시스템이 수면위에서 기폭 될 수 있도록 부이를 이용한 결선방법을 적용하여 수중발파를 실시하고 사례별 결과를 비교하였다. 그 결과, 수중발파 장약량 설계에 따른 지발당장약량에 따른 진동의 예측과 실 계측을 통하여 예측 진동식의 타당성을 검증하였으며, 장약의 방법과 결선방법에 따라 발생될 수 있는 불발을 최소화시킬 수 있을 것이다. 따라서, 최적발파 효과와 안전한 발파를 수행하기 위하여, 천공경은 150mm이상, 화약은 고성능 수중 다이너마이트(메가마이트 II), 그리고 뇌관은 비전기뇌관을 적용하는 것이 가장 유리할 것으로 판단된다.

• 대한교통학회지
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• 제27권6호
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• pp.29-44
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• 2009

실시간 교통자료 수집 기술의 혁신을 위해 유비퀴터스 환경기반의 교통정보시스템을 구성하는 인프라(RSE)의 적정 설치간격을 설정하는 방법론을 연구하였다. 적정설치간격을 도출하기 위해 연속류 교통상황 모니터링에 효과적으로 사용될 수 있는 구간통행시간을 평가척도로 설정하고, 인프라(RSE)의 통신반경 내에 위치하는 개별차량의 주행자료에서 속도자료를 추출하여 구간통행시간을 산출하였다. 교통상황에 따른 생성정보의 정확도와 적정 설치간격을 분석하기 위해 정상교통류와 교통사고로 인한 혼잡교통류 상황을 설정하여 개별차량 주행궤적을 수집하였다. RSE 설치간격, MPR(Market Penetration Rate), Time window를 주요변수로 정의하고 산출된 구간통행시간의 정확도를 MAPE(Mean Absolute Percentage Error)를 이용하여 평가하였다. 인프라(RSE) 설치간격 값은 1km에서 0.5km씩 증가시키면서 2.5km까지 적용하였다. 구간통행시간의 평가결과 2.5km의 간격으로 인프라(RSE)를 설치할 때 생성된 구간정보의 정확도가 급격히 감소되었다. 분석결과의 통계적 유의성을 평가하기 위해 분산분석을 수행하였다. 적정수준의 정확도가 확보된 구간정보의 생성이 가능하면서 인프라(RSE)를 최대간격으로 설치하기 위한 RSE 적정간격 설치방법론을 제시하였다. 본 연구에서 제시한 RSE의 적정설치간격 도출 방법론은 향후 차세대 교통수집체계인 유비퀴터스 환경기반 교통정보시스템의 요구사항 수립을 위해 효과적으로 사용될 것으로 기대된다.

• 보건행정학회지
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• 제8권1호
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• pp.155-182
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• 1998

There exists a remarkable differences in use of MRI scanning among income classes. The poor can hardly utilize it. This is because, among high cost technnologies, MRI is the only equipment not covered under health insurance benefits in Korea. This study was designed 1) to reveal the status of nation-wide MRI installation, customary charges and per unit annual scanning performance, and 2) to analyse factors influencing the above variables. The data for this study came from "MRI Prevalence Survey" conducted by the National Federation of Medcial Insurance(NFMI) in 1997, and were analyzed through SAS packages for T-test, analysis of variance and stepwise multiple regression. Data were collected from 188 hospitals equipped with MRI scanners. Major findings are summarized as follows : The number of MRI scanners has increased from 69 in 994 to 158 in 1996(2.3 times) while per unit annual scanning performance has risen by 11.2% from 2,173 cases in 1994 to 2,417 cases in 1996. Such a rapid increase was made possible mainly due to the inclusion of CT scanning under the health insurance benefit package. The customary charges for MRI scanning with or without contrast media, on average, amounted to 484,000 Won and 402,000 Won, respectively, with the percentile increase of 17.8% and 8.1% each during the same time. Korea ranks the third worldwidely in terms of number of MRI installations, 4.8 scanners per one million persons, only next to Japan and United States. Geographical variation of MRI, however, was rather high, 7.91 unit, in Cheju area compared to 1.82 in Kyongnam area. Variations of customary charges of MRI scanning can be explained as much as by 44.8% by both the total amount of claims to NFMI and geographical variable. The charges were more likely to be higher in metropolitan areas like Seoul and in hospitals with a bigger amount of claims. While those of per unit annual scanning performance can be explained as much as by 30.7% by both MRI installation cost and level of MRI-installed organizations. Per capital scannig performance was higher in tertiary hospitals and hospitals equipped with more expensive scanners than hospitals with less expensive scanners. Two measures are called for the remedying the existing excessive abundance in MRI units in korea : One is to set a ceiling of MRI units in an area like a province or a metropolitan district. The other is to establish a committee on introduction of high cost technologies for reviewing its effective use.ctive use.

• 대한지역사회영양학회지
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• 제12권5호
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• pp.617-629
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• 2007

To ensure the microbiological safety of food items prepared after cooking process, this study was aimed to identify the hazards related with cooked foods donated to foodbanks through quantitative microbial analysis. Five foodbanks located in Incheon and Gyeonggi area among government-dominant foodbanks were surveyed from February to June, 2007. Manager, recipient, donator, type and quantity of donated foot and facility and equipment were examined for the general characteristics of foodbank. The time and temperature of food md environment were measured at steps from after-production to before-distribution, and the microbial analysis was performed mainly with indicator organism and major pathogens. The amount of cooked foods donated to each foodbank was about 20 to 30 servings and consisted of 80% of total donated foods. Only three foodbanks had separate offices for foodbank operation and four institutions had at least one temperature-controlled vehicle. The flow of donated foods was gone through the steps; production, meal service and holding at donator, collection by foodbank, transport (or holding after transport) and distribution to recipients. It took about 3.8 to 6.5 hours at room temperature from after-production to before-distribution. Only aerobic plate counts (APC) and coliforms were found in microbial analysis. The APC after production were relatively high in $8.2{\times}10^5,\;7.4{\times}10^5,\;6.9{\times}10^5$ and $4.2{\times}10^5 CFU/g$ while $2.8{\times}10^6, \;9.4{\times}10^5,\;1.0{\times}10^6$ and $5.4{\times}10^5CFU/g$ before distribution in mixed Pimpinella brachycarpa, mixed chard mixed amaranth and mixed spinach, respectively. The levels of coliforms in mixed chard and mixed spinach were complied with the standards of the Ministry of Education and Human Resources Management The level of APC in boiled pork was increased from $< 1.0{\times}10 CFU/g$ to $4.0{\times}10^2 CFU/g$. One of delivery vessels was shown $6.2{\times}10^3 CFU/100 cm^2$ in APC, which was over the standards for environment. One of serving tables also showed the high level of $1.2{\times}10^3 CFU/100 cm^2$ in APC and $6.6{\times}10^2 CFU/100 cm^2$ in coliforms. These results suggest the sanitary management of holding at donator and the time-temperature control are key factors to ensure the safety of cooked foods donated to foodbank.