• Journal of Intelligence and Information Systems
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• v.29 no.4
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• pp.229-256
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• 2023

The increase in telecommuting and household electricity demand due to the pandemic has led to significant changes in electricity demand patterns. This has led to difficulties in identifying KEPCO's PPA (power purchase agreements) and residential solar power generation and has added to the challenges of electricity demand forecasting and grid operation for power exchanges. Unlike other energy resources, electricity is difficult to store, so it is essential to maintain a balance between energy production and consumption. A shortage or overproduction of electricity can cause significant instability in the energy system, so it is necessary to manage the supply and demand of electricity effectively. Especially in the Fourth Industrial Revolution, the importance of data has increased, and problems such as large-scale fires and power outages can have a severe impact. Therefore, in the field of electricity, it is crucial to accurately predict the amount of power generation, such as renewable energy, along with the exact demand for electricity, for proper power generation management, which helps to reduce unnecessary power production and efficiently utilize energy resources. In this study, we reviewed the renewable energy generation forecasting system, its objectives, and practical applications to construct optimal aggregated power resources using data from 169 power plants provided by the Ministry of Trade, Industry, and Energy, developed an aggregation algorithm considering the settlement of the forecasting system, and applied it to the analytical logic to synthesize and interpret the results. This study developed an optimal aggregation algorithm and derived an aggregation configuration (Result_Number 546) that reached 80.66% of the maximum settlement amount and identified plants that increase the settlement amount (B1783, B1729, N6002, S5044, B1782, N6006) and plants that decrease the settlement amount (S5034, S5023, S5031) when aggregating plants. This study is significant as the first study to develop an optimal aggregation algorithm using aggregated power resources as a research unit, and we expect that the results of this study can be used to improve the stability of the power system and efficiently utilize energy resources.

• International Commerce and Information Review
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• v.16 no.4
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• pp.247-261
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• 2014

In this study, it investigates the highly controversial issue "low carbon car subsidy". Through the policy's intent, purpose, and necessity, it aims to present alternatives for automotive industry development. Introducing the low carbon car subsidy will bring a huge change to the vehicle purchase practices by changing vehicle purchase cost. It expects that this change will reduce greenhouse gas emission from vehicles. For successful settlement of the system, it shall set up the target sections for subsidy and levy appropriately in order to get the nation's consensus. Additionally, it has to conduct sufficient reviews the measures such as adjustment to the existing auto tax, divided payments of burden charge, etc before enforcing the system. In terms of the automobile industry, it must do their level best in technical development in order to meet the carbon dioxide emission level of imported cars until the enforcement. Also, the government has to strengthen its support to the industry.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.109.1-109.1
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• 2016

진공산업 분야에서 OLED 디스플레이가 큰 시장으로 성장하며 크라이오 펌프가운데서 특별히 수분만 집중적으로 배기할 수 있는 워터펌프(CWP or cold trap)가 각광받고 있다. 이에 현민지브이티(Genesis)는 중소기업청 중소기업개발지원사업의 일환으로 진행된 2014년도 구매조건부 신제품 개발사업에 선정되어 '극저온 G-M냉동기를 이용한 대용량 Cold Trap개발'과제를 수행하면서 32인치 급으로 수분에 대해서 30,000[L/s] 이상의 배기속도를 가지는 대형 CWP를 개발하고 있다. 그 일환으로 본 CWP에 장착할 80K에서 200W급 단단 G-M 냉동기를 2015년 국내 최초로 개발하였다. 본 HPS80200(200W @80K) 단단 G-M냉동기에 대한 성능시험을 수행하던 중 기존 평가방식에 보완할 부분이 있음을 확인하였다. 통상적으로 G-M냉동기의 냉동능력은 저온 스테이지 상단에 온도센서와 히터가 설치된 히터 블럭을 장착한 후 일정한 열부하를 인가하면서 77K 또는 80K에서의 냉동능력을 측정한다. 문제는 여기에 설치하는 온도센서의 장착 위치의 중요성이다. 즉, 어느 부위의 온도를 냉동기의 대표 온도로 정하느냐에 따라 냉동기의 성능 값에 큰 차이를 나타내기 때문이다. 실제 확인 결과, 온도는 히터블럭 내의 위치뿐 아니라 저온 스테이지 부위별로도 크게 차이를 보였다. 따라서 본 연구에서는 보다 합리적이고 정확한 냉동 능력 측정을 위해 77K 에서 냉동기의 질소 액화 능력으로 냉동능력을 평가하고자 하였다. 이를 통해 개발된 HPS80200냉동기의 보다 정확한 냉동능력(77K에서 200W 이상임을 확인함)을 측정할 수 있었고 냉동기의 저온 스테이지에서 대표온도로 설정할 수 있는 위치도 확인할 수 있었다.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.109.2-109.2
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• 2016

현민지브이티(Genesis)는 중소기업청 중소기업개발지원사업의 일환으로 진행된 2014년도 구매조건부 신제품 개발사업에 선정되어 '극저온 G-M냉동기를 이용한 대용량 Cold Trap개발'과제를 수행하면서 32인치 급으로 수분에 대해서 30,000[L/s] 이상의 배기속도를 가지는 대형 CWP를 개발하고 있다. 1차년도(2015년) 목표는 80K에서 200W급 단단 G-M극저온 냉동기를 개발하는 것이고, 2차년도(2016년) 목표는 이를 장착하여 30,000[L/s]의 물 배기속도 능력을 갖춘 32인치(800mm)급 직부형(appendage) CWP를 개발하는 것이다. 여기에서 가장 큰 문제점은 CWP 시스템의 물 배기속도를 실제로 측정하는 것이다. 왜냐하면 지금까지는 물(H2O)이 가진 독특한 물리적 특성으로 인해 배기속도 측정에 많은 어려움이 있어 이론적으로 계산한 값을 사용해 왔다. (심지어 크라이오 펌프 제조사 조차도 실험하지 않고 이론적인 계산 값을 일반적으로 사용한다.) 그러나 최근 본 과제 외에 물 배기속도 측정에 관한 요구사례와 일부 크라이오 펌프 제조사에서 수행하고 있다는 보고가 있는 바, 실제 물배기속도 시스템을 구축하여 이론과 실제 사이의 차이와 측정의 어려움 등에 관해 규명하고자 하였다. 물 배기속도 측정 방법은 크게 2가지로 나눌 수 있다. 첫째, 시스템으로 흘리는 물의 양을 Liquid MFC를 이용하여 먼저 측정한 후 Vaporizer로 보내어 기화 시키며 배기속도를 측정하는 방법. 둘째, 물을 Vaporizer로 먼저 기화시킨 후에 High Temp. MFM으로 기체 유량을 측정하며 배기속도를 측정하는 방법이 그것이다. 이에 국내 최초로 두 가지 방법 모두를 사용하여 표준화 된 물 배기속도 측정 설비를 구축하였고, 20인치(500mm) 크라이오 펌프와 인라인(inline)형 CWP 모델에 대한 물 배기속도 측정을 성공적으로 완료할 수 있었다. 향후 본 시험 방법과 결과를 토대로 32인치(800mm) 직부형 CWP 모델에 대한 물 배기속도 측정시험을 수행하고자 한다.

• Journal of Energy Engineering
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• v.19 no.2
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• pp.92-102
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• 2010

Plug-in hybrid electric vehicle(PHEV) is a hybrid electric vehicle (HEV) with more added battery capacity that can be recharged from the electric power grid. Plug-in battery electric vehicle(PBEV) is a pure electric vehicle that uses only electric motor using electricity from battery that recharged from the power grid. PHEV and PBEV requires recharging of batteries in the vehicles from electric power grid. Recently, PHEVs and PBEV are being developed around the world. It is important to understand how these electric vehicles affect power demands and carbon dioxide emissions. From vehicle customer viewpoint, running energy cost will be imporatnt factor to consider. This paper analyzes the potential impacts of PHEVs and PBEVs on electric power demand, and associated CO2 emissions in 2020 with an projection that the vehicles will be penetrated with 10% market share. Energy costs for the vehicles are also calculated and compared with the conventional combustion vehicle.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.9
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• pp.876-883
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• 2008

A clearly defined e-catalog (or product) information is a key foundation for an e-commerce system. A classification (or categorization) is a core information to build clear e-catalogs, can play an important role in quality of e-commerce systems using e-catalogs. However, as the wide use of online business transactions, the volume of e-catalog information that needs to be managed in a system has become drastically large, and the classification task of such data has become highly complex. In this paper, we present an e-catalog classifier system, and report on our effort to improve an e-catalog management process and to standardize e-catalogs for enterprises by use of automated approach for e-catalog classifier systems. Also we introduce some of the issues that we have experienced in the projects, so that our work may help those who do a similar project in the future.

• The KIPS Transactions:PartD
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• v.19D no.2
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• pp.127-132
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• 2012

In the Seoul metropolitan bus network, it may be necessary for a bus passenger to pick up a parcel, which has been purchased through e-commerce, at his or her convenient bus stop on the way to home or office. The flow-capturing location-allocation model can be applied to select pickup points for such bus stops so that they maximize the captured passenger flows, where each passenger flow represents an origin-destination (O-D) pair of a passenger trip. In this paper, we propose a fast heuristic algorithm to select pickup points using a large O-D matrix, which has been extracted from five million transportation card transactions. The experimental results demonstrate the bus stops chosen as pickup points in terms of passenger flow and capture ratio, and illustrate the spatial distribution of the top 20 pickup points on a map.

• The Journal of Bigdata
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• v.4 no.2
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• pp.115-126
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• 2019

There have been many discussions on export indices in trade exports, but there is no definite trade export index which can be explained by objective indicators. Korea International Trade Association (KITA), Korea Trade-Investment Promotion Agency (KOTRA), etc., but we are currently in the process of thinking about ways to express the capabilities of exporting companies. In this study, we constructed the AI data sets by setting the activity indicators such as the size of the company and the credit score, the number of transaction customers, the number of transactions, the number of items, the transaction volume, and the transaction period as features, Lightgbm. Using the Graph Neural Network as an industrial cluster classification model, the export live index which expresses the exportable capacity among companies, items, and business groups was calculated. This includes the past activity of the company from the current calculating index Objectivity.

• Asia pacific journal of information systems
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• v.16 no.4
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• pp.49-70
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• 2006

In recent, Open markets are booming up rapidly. Open markets are one of the online marketplaces which mainly concentrated on spot transactions of commodities, and are differentiated from integrated internet shopping stores with market participants, trading rules and so on. This study investigated on factors affecting satisfaction with and preference on open markets by comparing open markets with integrated internet shopping stores, and aimed to figure out the reasons why open markets are growing up so rapidly and to forecast the future of open markets. To investigate the factors affecting buyers' satisfaction with and preference on internet shopping channel. I extracted several factors through literature reviews. The factors include the pros (cost saving and time saving), the cons (security concerns and privacy concerns), and decision making support suggested by Simon's research as well. Then, I constructed research model and related research hypotheses. To verify research hypotheses, I conducted field survey targeting on online buyers and analyzed research data using structural equation model. According to data analysis result, open markets have competitive advantages over integrated internet shopping stores with respect to cost saving, time saving, and decision making support. However, online buyers are still concerning privacy issues within open markets. In summary, buyers are considering that open markets are cheaper, faster, and more efficient internet shopping channel, compared with integrated internet shopping stores. However, open markets are required to dedicate to lessen buyers' privacy concerns to rebirth as more satisfying and preferable internet shopping channel and to prosper in the future.

• Journal of the Korea Society of Computer and Information
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• v.25 no.11
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• pp.167-178
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• 2020

This study attempted to find out the difference in the patterns of jeogori between commercially available Shinhanbok brands by comparing and analyzing the patterns of the changing Shinhanbok jeogori in consideration of material characteristics, fit, and fastening. After purchasing and disassembling 6 products, analysis was conducted with the disassembly pattern. As a result of analyzing the shape of the jeogori, the 1st, 3rd and 6th brands showed no darts. In the case of the 5th brand, the three-dimensional effect of the human body was expressed with a princess line. As a result of the appearance evaluation, the 5 brands were evaluated as the highest in most items except for the space of the front width and the group wrinkles of back sleeve armhole, and the appearance was analyzed to be the best. As a result of evaluating the clothing pressure, it was analyzed that the chest circumference of the first brand was smaller than that of the other brands, and the shoulder width and shoulder length were also shorter, and pulling occurred even after wearing. As the demand for new hanbok increases, it is believed that it is necessary to establish a size system for ready-made clothes.