• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.937-944
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• 2022

Electric vehicles (EVs) have been growing to reduce energy consumption and greenhouse gas (GHG) emissions in the transportation sector. The increasing number of EVs requires adequate recharging infrastructure, and at the same time, adopts low- or zero-emission electricity production because the GHG emissions are highly dependent on primary sources of electricity production. Although previous research has studied solar photovoltaic (PV) -integrated EV charging stations, it is challenging to optimize spatial areas between where the charging stations are required and where the renewable energy sources (i.e., solar photovoltaic (PV)) are accessible. Therefore, the primary objective of this research is to support decisions of siting EV charging stations using a spatial data clustering method integrated with Geographic Information System (GIS). This research explores spatial relationships of PV power outputs (i.e., supply) and traffic flow (i.e., demand) and tests a community in the state of Indiana, USA for optimal sitting of EV charging stations. Under the assumption that EV charging stations should be placed where the potential electricity production and traffic flow are high to match supply and demand, this research identified three areas for installing EV charging stations powered by rooftop PV in the study area. The proposed strategies will drive the transition of existing energy infrastructure into decentralized power systems. This research will ultimately contribute to enhancing economic efficiency and environmental sustainability by enabling significant reductions in electricity distribution loss and GHG emissions driven by transportation energy.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.10-10
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• 2022

The concern about food security is rising as the unstable situation of food supply and demand due to the Covid-19 pandemic, climate change, and turbulent political situation. Korea's global food security index (GFSI), analyzed by the Economist Group, is considered good, but the level continuously decreases in comparing food security levels by country. In particular, Korea is highly dependent on food imports, and food and grain self-sufficiency rates continuously decrease. Therefore, increasing those rates to strengthen food security is urgent. Among the major grains, the self-sufficiency of wheat, com, and soybeans, except rice, is relatively low. Unlike the decrease in the annual rice consumption, the annual wheat consumption has been continuously maintained or increased, which is required public-private efforts to increase the self-sufficiency rate of wheat. Applying the government's policies implemented to increase the self-sufficiency rate of rice in the past will help increase the self-sufficiency rate of wheat. In other words, expanding wheat production and infrastructure, stabilizing supply and demand, and establishing a distribution system can be applied. However, the processing capability of wheat and rice is different, which is necessary to improve wheat quality and processing technology to produce consumer-preferred wheat-based products. The wheat and flour quality can be improved through breeding, cultivation, post-harvest management, and milling. In addition, research on formulation, processes, packaging, and storage to improve the quality of wheat-based products should be done continuously. Overall, food security could be strengthened by expanding wheat production and consumption, improving wheat quality, and increasing wheat self-sufficiency.

• 대한토목학회논문집
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• 제39권1호
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• pp.81-91
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• 2019

도시철도역사 이용자는 철도역 주변의 토지이용계획에 많은 영향을 받으나, 우리나라는 이와 관련된 연구는 미진한 상태로 토지이용계획에 상관없이 일률적으로 출입구 너비를 산정하여 일부 출입구에서는 대기행렬이 발생 하거나 이용자가 거의 없는 등 편차를 보인다. 따라서 본 연구에서는 도시철도역 출입구별 이용수요 추정 모형을 정립하고자 하며, 이를 위해 도시철도역 20개소를 대상으로 출입구별 이용수요, 토지이용면적, 사회경제지표 등을 철도역 중심으로 200 m, 500 m로 조사하여 다중회귀모형을 정립하였다. 모형의 종속변수(반응변수)를 1일, 첨두 1시간, 첨두 시간대 5분 동안의 철도역 방향별 유출입 이용수요로 설정하고, 철도역 반경 500 m, 200 m 범위의 토지용도(주거, 상업 업무, 공업, 교육, 공원) 면적과 사회경제지표(인구, 고용자, 종사자, 학생)를 독립변수(설명변수)로 설정하였다. 그 결과 도시철도 중심 반경 500 m 내 토지용도별 이용면적을 독립변수, 철도역 1일 유출입 이용수요를 종속변수로 사용하는 것이 모형의 적합도가 통계적으로 더 유의한 것으로 분석 되었다. 본 연구는 도시철도역의 이용자 및 교통약자의 이동 편의성 개선을 위해 도시철도 출입구 적정 규모 산정을 위한 기초 연구로 추후 교통약자 이용자 수를 반영하여 출입구별 이용자 수 추정, 교통약자 편의시설 적정 규모 산정 시 활용 가능할 것으로 보인다.

• 문화기술의 융합
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• 제8권6호
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• pp.655-660
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• 2022

본 논문은 공급 업체(Supplier), 소매 업체(retailer) 및 고객(Cuistomer)으로 구성된 2 단계 공급망(Supply Chain)에서 소매 업체의 경제적 주문량(로트 크기)에 대한 문제를 분석하고자 한다. 이와 같은 2 단계 공급망에서 공급 업체는 경쟁 기업과의 가격 차별화 전략으로 소매 업체가 지불해야 할 상품 구입비용에 대해 일정 기간 지불 유예를 허용하기도 한다. 또한 식품, 곡물 등의 소비재의 경우 일반적으로 최종 고객의 수요는 소매 업체의 진열된 재고 수준에 따라 종속적으로 나타나는 것을 흔히 볼 수가 있다. 따라서 본 연구에서는 이와 같은 관점에서 공급업체가상품 구입비용에 대해 소매 업체에 일정 기간 지불 유예를 허용하는 경우에 고객의 수요가 소매 업체의 재고 수준에 크기에 따라 증가하는 함수라는 가정 하에 소매 업체의 재고 문제를 분석 해 보고자 한다. 공급 업체가 허용하는 지불 유예 기간이 소매 업체의 재고 정책에 미치는 영향을 분석하기 위하여 몇 가지 지불 유예 기간에 대한 소매 업체의 경제적 주문량을 결정 해 봄으로써 상품 구입비용에 대한 지불 유예 기간의 길이가 소매 업체의 재고 정책에 미치는 영향에 대하여 계량적으로 분석 해 보고자 한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.759-762
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• 2005

Recently, Intelligent Transportation System(ITS) has been applied to satisfy increasing traffic demand every year and to solve many traffic problems. Especially, Advanced Traveller Information System(ATIS) is a transportation system to optimize the trip of each other vehicle. It is important to provide the driver with quick and comfortable path from source to destination. However, it is difficult to provide a shortest path in a road network with dynamic cost. Because the existing research has a static cost. Therefore, in this paper we propose an operator for searching traffic dependent shortest path. The proposed operator finds the shortest path from source to destination using a current time cost and a difference cost of past time cost. Such a method can be applied to the road status with time. Also, we can expect a predicted arrival time as well as the shortest path from source to destination. It can be applied to efficiently application service as ITS and have the advantages of using the road efficiently, reducing the distribution cost, preparing an emergency quickly, reducing the trip time, and reducing an environmental pollution owing to the saving the fuel.

• 산학경영연구
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• 제4권
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• pp.281-295
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• 1991

Nothing is more incorrect than forecasting. Nevertheless, forecasting is one of the most important business activities for the effective management. There has been rapid changes of the growth rate in every respect of the Korean hospitaity industry, especially the hotel industry, before and after the 88 Olympic Games. Therefore, the hoteliers shall be in need of more-than-ever accourate demand forecasting for the more systematic management and control. Under the above circumstances, this study suggested the best forecasting technique and method for the better sales and operations of the hotel rooms. The number of rooms sold is selected as a dependent variable of this study which is regarded as the best representative factor of measuring the growth rate of the rooms division performance of the hotels. The first step was to select the most verifiable independent variable diferently from the other countries or other areas of Korea. As a result, the number of foreign visitors was chosen. Empirical research, i.e. correlation and multiple regression analysis, shows that this independent variable has a strong relationship with the dependent variable told above. The second procedure was to estimate the number of rooms will be sold in 1991 on the basis of the formula calculated through the multiple regression analysis. Time series technique was conducted using the data of the number of foreign visitors by purpose of travel from 1987 to 1990. For the more correct forecasting, however, it would be desirable to adopt the data from 1989 considering the product or the industry life cycle. In addition, deeper analysis for the monthly or seasonal forecasting method is needed as a future research.

• 전자공학회논문지SC
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• 제44권1호
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• pp.50-58
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• 2007

본 논문에서는 로봇이 태스크와 관련된 부분에 시각 집중을 하도록 하기 위해서 기존의 상향식 주목 알고리즘을 확장한 질의 기반 시각 집중 알고리즘을 제안한다. 질의 기반 시각 집중 알고리즘은 로봇이 수행 할 태스크와 관련한 물체를 질의하면 그 물체의 속성을 분석하여 여러 종류의 도드라짐(Conspicuity) 영상 지도에 적용될 가중치 값을 작성한다. 그리고 가중치를 이용하여 도드라짐 영상 지도를을 합성한 Saliency 영상 지도를 작성하여 기존의 주목 알고리즘과 비교 평가를 수행하였다. 여기서는 일예로서 질의 물체의 속성을 색으로 사용하였다.

• 산업경영시스템학회지
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• 제43권1호
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• pp.70-78
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• 2020

Under the situation which customer orders are cancelled unless all products in the order are delivered all at once, this paper concentrates on the purchase dependent demands and explores the systematic approach to implant the purchase dependence into the multi-product inventory model. First, by acknowledging that it is a challenging task to formulate a suitable inventory model for the purchase dependence, we derive the optimal solution condition using an EOQ model and extend the optimal solution condition to periodic review models. Then, through the comparison simulation of four inventory policies regarding several degrees of purchase dependence, we demonstrate that the inventory models which consider the purchase dependence generate less total cost than the inventory models which ignore the purchase dependence. In general, the inventory models which consider the purchase dependence reduce the loss of sales by maintaining more inventories, which results in reducing the total cost. Consequently, the simulation result supports the effectiveness of this paper's approach. In addition, this paper uses the individual order period and joint order period obtained from the EOQ model for the multi-product inventory model. Through the in-depth analysis of comparing the two models, we observe that the model of using the joint order period produces less total cost when the degree of purchase dependence is high, but the model of using the individual order period produces less total cost when the degree of purchase dependence is low.

• 사회경제평론
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• 제38호
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• pp.199-240
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• 2012

포스트케인즈학파(PK) 내생화폐이론에 따르면, 기업은 신규투자를 수행하기 위해 은행에 대한 대부수요를 만들고, 이에 대한 은행의 대출공급으로 예금화폐가 창조된다. 은행의 자산 측면에서의 신용창조가 부채측면에서 화폐창조로 이어지면서 은행의 대차대조표에서 실물과 화폐가 연결된다. 이 글은 은행의 기능을 중심으로 황재홍(2005)에 대한 비판적 고찰을 통하여 케인즈와 PK 내생화폐이론을 살펴보고자 한다. 이로써 다음과 같은 결론이 도출된다. 첫째, PK 내생화폐이론의 기반을 케인즈에게서 찾을 수 있다. 둘째, 케인즈의 화폐내생성과 빅셀의 그것은 본질적 측면에서 서로 다르다. 마지막으로, PK 내부의 수평주의자와 구조주의자의 논쟁을 이들의 논의의 결론이 아닌 분석상의 차이점에 초점을 두고 보면, 내생화폐이론과 유동성 선호이론은 케인즈 이론 체계에서 양립가능한 이론이 될 수 있다.

• 유통과학연구
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• 제20권4호
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• pp.95-100
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• 2022

Purpose: This study aimed to investigate whether distribution and service companies maintained their accounting information quality and provided reliable information despite the economic changes occurring after the outbreak of the COVID-19 pandemic in Korea. The distribution industry has enjoyed increased demand as many companies expanded their untact distribution channels, including to online sales. However, as the pandemic drags on, their future prospects remain uncertain. Research design, data, and methodology: In this study, we define 2018-2019 as the "pre COVID-19 period" and 2020 as the "post COVID-19 period." An empirical analysis was performed using a regression model that includes POST, the independent variable, indicating the post COVID-19 period, and discretionary accruals(DA), a proxy for earnings management, as a dependent variable. Results: The analysis shows that the coefficient of POST is significantly positive (+) for the dependent variable DA. This finding suggests that distribution and service companies engaged in more earnings management during the post COVID-19 period than during the pre COVID-19 period, indicating their awareness of the uncertainty of future business performance as the pandemic persists. An additional analysis confirmed that smaller companies with fewer stakeholders and higher information asymmetry tend to engage more in earnings management than larger companies.