• Safety and Health at Work
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• 제11권2호
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• pp.178-186
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• 2020

Background: Cognitive impairment is a public health burden. Our objective was to investigate associations between work hours and cognitive function. Methods: Multi-Ethnic Study of Atherosclerosis (MESA) participants (n = 2,497; 50.7% men; age range 44-84 years) reported hours per week worked in all jobs in Exams 1 (2000-2002), 2 (2002-2004), 3 (2004-2005), and 5 (2010-2011). Cognitive function was assessed (Exam 5) using the Cognitive Abilities Screening Instrument (version 2), a measure of global cognitive functioning; the Digit Symbol Coding, a measure of processing speed; and the Digit Span test, a measure of attention and working memory. We used a prospective approach and linear regression to assess associations for every 10 hours of work. Results: Among all participants, associations of hours worked with cognitive function of any type were not statistically significant. In occupation-stratified analyses (interaction p = 0.051), longer work hours were associated with poorer global cognitive function among Sales/Office and blue-collar workers, after adjustment for age, sex, physical activity, body mass index, race/ethnicity, educational level, annual income, history of heart attack, diabetes, apolipoprotein E-epsilon 4 allele (ApoE4) status, birth-place, number of years in the United States, language spoken at MESA Exam 1, and work hours at Exam 5 (β = -0.55, 95% CI = -0.99, -0.09) and (β = -0.80, -1.51, -0.09), respectively. In occupation-stratified analyses (interaction p = 0.040), we also observed an inverse association with processing speed among blue-collar workers (adjusted β = -0.80, -1.52, -0.07). Sex, race/ethnicity, and ApoE4 did not significantly modify associations between work hours and cognitive function. Conclusion: Weak inverse associations were observed between work hours and cognitive function among Sales/Office and blue-collar workers.

• 대한지역사회영양학회지
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• 제10권6호
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• pp.905-919
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• 2005

This study raised the necessity of developing performance indicators for measuring the management efficiency and effectiveness of school food service, and as a means of helping its implementation, a balanced score card (BSC) approach developed by Norton and Kaplan was adopted. This study established BSC in seven phases through literature: Phase 1 Defining a school food service and the scope of working activities, Phase 2 Establishing the vision of a school food service, Phase 3 Setting strategic goals, Phase 4 Identifying critical success factors (CSFs), Phase 5 Developing Key Performance Indicators (KPIs), Phase 6 Extracting cause and effect relationship, and Phase 7 Completing a preliminary BSC. The preliminary BSC was fumed into a survey, which was administered to food service related people working at the Office of Education and School Food Service including 16 offices,209 dietitians, 48 school administrators both from self-operated and contract-managed, and 9 experts in areas related to school food service. They were asked questions about strategies from 4 different perspectives,12 CSFs, 39 KPls, and the cause and effect relationships among them. As a result, among the CSFs based on 4 different perspectives, all factors other than ' zero sum on profit/loss ' from the financial perspective turned out to be valid. In terms of KPIs, manufacturing cost percentages, casualty loss count/reduction rates, school foodervice participation rates, and sales goal achievement rates were found to be valid from the financial perspective, while student satisfaction index, faculty satisfaction index, leftover ratio, nutrition educational performance count, index of evaluating nutrition education, customer claim count/reduction rate, handling customer claim count/reduction rate, and parent satisfaction index were found to be valid from the customers' perspective. Besides, nutritional requirement sufficient ratio, nutritional management score, food poisoning outbreak count, employee safety accident count, sanitary inspection assessment index, meals per labor hour (productivity index), computerization ratio, operational management index, and purchase management assessment index were also found to be valid from the perspective of internal business processes. From the perspective of innovation and learning, employee turnover ratio/rate of absenteeism, annual education and training count, employee satisfaction index, human resource management assessment index, annual menu-related customer feedback, food service information index for employees and parents/schools were also found to be valid. The significance of this study is to present indices for measuring overall performance of school lunch food service operations without putting any limitation on types of school food service management, and to help correctly assess the contribution of the current types of school food service management to schools and students. (Korean J Community Nutrition 10(6) : $905\∼919$, 2005)

• 한국항해항만학회지
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• 제39권3호
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• pp.267-275
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• 2015

항만물류산업은 교역과 부가가치 창출, 높은 경제적 효과를 지닌 중요한 산업으로 그 영역이 점차 확대되고 있다. 항만물류산업의 효율화는 국가 경쟁력을 증대할 수 있는 방안 중 하나이며, 다수의 선행연구에서 그 영향에 대해 연구가 진행되었다. 본 연구에서 산업 분류의 기준이 되는 한국표준산업분류의 9차 개정을 활용하고, 2010년 최초 시행된 경제총조사 자료를 활용하여 울산지역을 대상으로 항만물류산업이 지역경제에 미치는 영향을 분석하고, 우리나라 5대 항만도시간 항만물류산업을 비교하였다. 연구 결과, 첫째 2010년 기준 직접 항만물류산업은 종사자(11.7%)와 매출액(13.1%)에서 높은 비중을 보였으며, 지역 내 높은 고용과 경제적 영향이 있음을 나타냈다. 둘째, 5대 항만도시의 2007~2011년 기준 항만물류산업간 비교에서 광양(5.72%)과 울산(4.23%)은 전국평균(1.74%)보다 높은 사업체수의 연평균 증가와, 직접 항만물류산업의 종사자에서 울산(23.82%), 평택(25.74%)은 높은 연평균 증가를 나타냈다.

• 한국산업보건학회지
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• 제24권1호
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• pp.59-64
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• 2014

Objectives: The principal aim of this study is to investigate and analyze domestic usage amounts of insecticide in rice cultivation in order to provide fundamental data for establishing a job-exposure matrix(JEM) related to farmers working with agricultural insecticides. Materials and Methods: An investigation of domestic usage amounts of insecticides rice cultivation was performed through two methods. The first method utilized information on agricultural pesticides published annually by the Korea Crop Protection Association(KCPA). The second method made use of area of cultivation of rice as officially determined by Statistics Korea(SK). An estimation of domestic usage of insecticides in rice cultivation through the second method was determined by multiplying the total cultivation area of rice($m^2$) by the optimal spray volume of insecticides for rice cultivation per unit of cultivation area($kg/m^2$). Results: As a result of the analysis of public data regarding insecticides in rice cultivation, it was found that the domestic usage amount has decreased sharply from the first year of market sales(1969) to the final data year(2012). There is little difference in the annual usage trend of insecticides in rice cultivation between shipment and estimation. Also, the annual usage trends of insecticides in rice cultivation based on regional classification were nearly similar to those based on the overall aspect. Conclusions: The region which used the largest volume of insecticide in rice cultivation in Korea was the Jeolla Provinces, followed by the Gyeonsang Provinces, the Chungcheong Provinces, Seoul/Gyeonggi Province, Gangwon Province and Jeju Province. Substantially, the mean ratio of usage amounts of insecticide based on shipments and those based on estimation by cultivation area was $96{\pm}29%$, which indicates that the domestic usage amount of insecticide for rice cultivation corresponded to the optimal spray standard per unit area.

• 한국프랜차이즈경영연구
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• 제3권2호
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• pp.20-38
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• 2012

본 연구의 목적은 예비가맹사업자가 창업을 준비할 때 프랜차이즈가 성공할 수 있는 가맹본부를 선별할 수 있는 기준을 살펴보고, 프랜차이즈 사업의 위험요소 감소와 성공적인 방향을 제시하는데 의의가 있다. 특히 공정거래위원회에서 제시하고 있는 정보공개서 분석을 중심으로 도출된 2922 표본 중 2개년도, 가맹점 10개 이상 등의 조건과 결측치를 제외한 511개의 표본을 대상으로 분석하였다(2012년 8월 20일 기준). 선행연구를 통한 프랜차이즈 특성을 도출하였고, SPSS 18.1을 통해 빈도분석과 회귀분석을 실시하여 특성분석과 가맹점 사업성과 간의 영향을 살펴보았다. 연구결과, 첫째, 프랜차이즈 본부 특성은 전반적으로 소상공인이나 중소기업 규모(총점포 수, 재무재표 등)로 운영되고 있으며, 대부분 업종이 기타 외식에 집중되어 있었다. 특히 프랜차이즈의 영업지역의 보호라는 관점에서 비보호를 대부분 채택하고 있다. 둘째, 프랜차이즈 특성과 성과간의 관계에서 연평균매출액과 당기순이익에서는 영향을 미치는 것으로 나타났으나 성장률에 해당되는 가맹점증가율 지표에는 영향을 미치지 못하는 것으로 도출되었다. 마지막으로 프랜차이즈 특성들과 성과간의 차이분석에서는 업종구분을 제외한 대부분의 특성들이 연평균매출액과 연평균당기순이익에 차이가 있는 것으로 나타났으며, 가맹점증가율에는 차이가 없는 것으로 나타났다. 연구결과를 통해 지속가능한 성장이 될 수 있는 방안이 마련해야 하며, 프랜차이즈의 권익보호를 위한 발판을 마련할 필요가 있다. 본 연구는 공시된 데이터를 바탕으로 관계에 관한 연구를 해보았다는 점에서 의의가 있다.

• 마케팅과학연구
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• 제19권1호
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• pp.37-46
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• 2009

The Census Bureau of the Department of Commerce announced in May 2008 that U.S. retail e-commerce sales for 2006 reached $ 107 billion, up from $ 87 billion in 2005 - an increase of 22 percent. From 2001 to 2006, retail e-sales increased at an average annual growth rate of 25.4 percent. The explosive growth of E-Commerce has caused profound changes in marketing channel relationships and structures in many industries. Despite the great potential implications for both academicians and practitioners, there still exists a great deal of uncertainty about the impact of the Internet channel introduction on distribution channel management. The purpose of this study is to investigate how the ownership of the new Internet channel affects the existing channel members and consumers. To explore the above research questions, this study conducts well-controlled mathematical experiments to isolate the impact of the Internet channel by comparing before and after the Internet channel entry. The model consists of a monopolist manufacturer selling its product through a channel system including one independent physical store before the entry of an Internet store. The addition of the Internet store to this channel system results in a mixed channel comprised of two different types of channels. The new Internet store can be launched by the independent physical store such as Bestbuy. In this case, the physical retailer coordinates the two types of stores to maximize the joint profits from the two stores. The Internet store also can be introduced by an independent Internet retailer such as Amazon. In this case, a retail level competition occurs between the two types of stores. Although the manufacturer sells only one product, consumers view each product-outlet pair as a unique offering. Thus, the introduction of the Internet channel provides two product offerings for consumers. The channel structures analyzed in this study are illustrated in Fig.1. It is assumed that the manufacturer plays as a Stackelberg leader maximizing its own profits with the foresight of the independent retailer's optimal responses as typically assumed in previous analytical channel studies. As a Stackelberg follower, the independent physical retailer or independent Internet retailer maximizes its own profits, conditional on the manufacturer's wholesale price. The price competition between two the independent retailers is assumed to be a Bertrand Nash game. For simplicity, the marginal cost is set at zero, as typically assumed in this type of study. In order to explore the research questions above, this study develops a game theoretic model that possesses the following three key characteristics. First, the model explicitly captures the fact that an Internet channel and a physical store exist in two independent dimensions (one in physical space and the other in cyber space). This enables this model to demonstrate that the effect of adding an Internet store is different from that of adding another physical store. Second, the model reflects the fact that consumers are heterogeneous in their preferences for using a physical store and for using an Internet channel. Third, the model captures the vertical strategic interactions between an upstream manufacturer and a downstream retailer, making it possible to analyze the channel structure issues discussed in this paper. Although numerous previous models capture this vertical dimension of marketing channels, none simultaneously incorporates the three characteristics reflected in this model. The analysis results are summarized in Table 1. When the new Internet channel is introduced by the existing physical retailer and the retailer coordinates both types of stores to maximize the joint profits from the both stores, retail prices increase due to a combination of the coordination of the retail prices and the wider market coverage. The quantity sold does not significantly increase despite the wider market coverage, because the excessively high retail prices alleviate the market coverage effect to a degree. Interestingly, the coordinated total retail profits are lower than the combined retail profits of two competing independent retailers. This implies that when a physical retailer opens an Internet channel, the retailers could be better off managing the two channels separately rather than coordinating them, unless they have the foresight of the manufacturer's pricing behavior. It is also found that the introduction of an Internet channel affects the power balance of the channel. The retail competition is strong when an independent Internet store joins a channel with an independent physical retailer. This implies that each retailer in this structure has weak channel power. Due to intense retail competition, the manufacturer uses its channel power to increase its wholesale price to extract more profits from the total channel profit. However, the retailers cannot increase retail prices accordingly because of the intense retail level competition, leading to lower channel power. In this case, consumer welfare increases due to the wider market coverage and lower retail prices caused by the retail competition. The model employed for this study is not designed to capture all the characteristics of the Internet channel. The theoretical model in this study can also be applied for any stores that are not geographically constrained such as TV home shopping or catalog sales via mail. The reasons the model in this study is names as "Internet" are as follows: first, the most representative example of the stores that are not geographically constrained is the Internet. Second, catalog sales usually determine the target markets using the pre-specified mailing lists. In this aspect, the model used in this study is closer to the Internet than catalog sales. However, it would be a desirable future research direction to mathematically and theoretically distinguish the core differences among the stores that are not geographically constrained. The model is simplified by a set of assumptions to obtain mathematical traceability. First, this study assumes the price is the only strategic tool for competition. In the real world, however, various marketing variables can be used for competition. Therefore, a more realistic model can be designed if a model incorporates other various marketing variables such as service levels or operation costs. Second, this study assumes the market with one monopoly manufacturer. Therefore, the results from this study should be carefully interpreted considering this limitation. Future research could extend this limitation by introducing manufacturer level competition. Finally, some of the results are drawn from the assumption that the monopoly manufacturer is the Stackelberg leader. Although this is a standard assumption among game theoretic studies of this kind, we could gain deeper understanding and generalize our findings beyond this assumption if the model is analyzed by different game rules.

• 산업진흥연구
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• 제5권4호
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• pp.15-28
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• 2020

본 연구에서는 방산시장의 시장구조와 경쟁현황을 측정하기 위한 방법 및 방위산업과 방산시장의 특징을 살펴보고, 연도별 주요 방산업체 매출액을 바탕으로 시장점유율 및 상위 기업집중률, 허핀달-허쉬만 지수를 적용하여 시장구조와 경쟁현황을 분석해 봄으로써 국내 방산시장이 독과점구조에서 벗어나 경쟁지향적 시장 형태로 변화하도록 개선방안을 제안하고자 한다. 이를 위해 방산시장과 유사한 형태의 시장들을 비교·분석하였으며, 그 결과를 바탕으로 방산업체의 다양한 공급능력 구비를 위한 정부의 지원정책 추진, 정부 주도하 방산제품의 공급 시기, 규모, 기간을 고려한 기업 선정, 군 소요에 대한 정보 제공 등의 개선사항을 제안하였다. 이는 정부가 정책을 추진하는데 있어 근본적인 시장구조 개선 및 산업 차원의 정책개발을 통해 공정하고 원칙에 맞는 방산시장을 조성하여 기업 운영의 효율성을 추구하기 위함에 있다.

• 복식문화연구
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• 제24권2호
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• pp.248-262
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• 2016

Most Korean companies in the fashion industry are SMEs, and the role of the CEO and management ownership is important for enhancing the firm's competence and developing strategies. The study aims to examine the effect of management ownership on company financial growth. In particular, the study focuses on the moderating effect of company age and size on Korean fashion SMEs' financial outcomes. Financial data based on company financial statements from 2012 to 2014 was collected by the Data Analysis, Retrieval and Transfer System of Korea's Financial Supervisory Service. A total of 295 companies' (domestic fashion businesses) data was analyzed by the bootstrap method. The median sales value in the financial year 2014 was 47,492,403,958 KRW, and the company size was divided by it. The companies were in business for an average of 20 years. According to the results, the management ownership had a negative effect on Compound Annual Growth Rate (CAGR) for the three-years, and the relationship between the two variables was moderated by company age. Additionally, the interaction effect of management ownership and company age on 3-CAGR was also moderated by company size. When the companies had spent only a few years in business, a negative effect of management ownership for small firms and a positive effect of management ownership on financial growth for medium firms were found. These results suggest that small companies starting business need to manage their company governance structure to make flexible decisions, and after retaining financial growth, the companies can expand their businesses based on strong ownership.

• 신재생에너지
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• 제16권1호
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• pp.47-57
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• 2020

In Floating PV (Photovoltaic) systems, PV modules are installed on water by utilizing the surface of idle water such as a reservoir and multipurpose dam. A floating PV system, therefore, has the advantage of efficiency in national land use and improved energy yield owing to cooling effect compared to on-land PV systems. Owing to the limitation of installation environment for a floating PV system, the system, however, has the disadvantage of an increase in transmission distance of DC (Direct current) cables. A longer transmission distance of a DC cable results in greater power loss due to a voltage drop. This leads to a decline in economic feasibility for the floating PV system. In this paper, the economic analysis for 10 floating PV systems installed in a reservoir has been conducted in terms of a change in annual power sales according to the variation of transmission losses depending on the factors affecting the voltage drop, such as transmission distance, cross-section area of underwater cable, the presence of joint box, and PV capacity.

• 한국물환경학회지
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• 제32권6호
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• pp.628-648
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• 2016

Increased attention has been paid to the presence of veterinary antibiotics in various environmental matrices due to their toxicological behavior in the ecosystem and development of antibiotic-resistant strains of pathogenic bacteria. In the this review, 37 target antimicrobials were selected based on annual sales of antibiotics for livestock in South Korea 2014. Also, extraction and clean-up methods for the determination of the antibiotic residues in liquid samples including water, milk, and honey were comprehensively reviewed in the literature. Solid-phase extraction (SPE) was commonly used as a pre-treatment method for the samples. Most of the analytes were extracted in acidic conditions (2.5~4.0) except for aminoglycosides, which were extracted in neutral conditions (7.0~8.0). ${\beta}-Lactams$ showed the highest recoveries in neutral pH due to their degradation characteristics in acidic media. Starta-X, Oasis HLB, and Oasis MCX were frequently applied as an SPE cartridge and Oasis HLB showed the highest recoveries for the majority of antibiotic classes. The homogenized honey and milk were extracted by mixing with acids for deproteinization. Solids and other interfering substances in the extract were eliminated by centrifugation followed by membrane filtration or SPE before injection into HPLC.