• 제목/요약/키워드: model based

검색결과 60,343건 처리시간 0.082초

Efficiency Analysis for Certified Integrated Logistics Warehousing firms Using DEA (DEA를 이용한 종합물류인증기업의 효율성 분석 : 물류창고업종을 중심으로)

  • Kang, Da-Yeon;Lee, Ki-Se
    • Journal of Navigation and Port Research
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    • 제43권4호
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    • pp.256-263
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    • 2019
  • The trade volume of Northeast Asian countries is increasing and with the advent of the 4th revolutionary era, minimizing the logistics costs of firm is becoming an important competitive factor. With respect to this, in 2006, the government introduced a certified Integrated logistics firm system to improve the competitiveness of local logistics firms and reduce the logistics costs of firms. They argued that the certified Integrated logistics firm system increased the reliability of logistics firms and increased the efficiency of the logistics industry. On the other side, they argue that the system puts a burden on firms and becomes a big business-oriented market consolidation. This study analyzed the efficiency of Warehousing firms using DEA model. The CCR, BBC efficiency and RTS (return to scale) of 15 Warehousing firms were evaluated. This study also suggested the Warehousing firms which can be benchmarked based on analyzed information.

Improvement of precipitation forecasting skill of ECMWF data using multi-layer perceptron technique (다층퍼셉트론 기법을 이용한 ECMWF 예측자료의 강수예측 정확도 향상)

  • Lee, Seungsoo;Kim, Gayoung;Yoon, Soonjo;An, Hyunuk
    • Journal of Korea Water Resources Association
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    • 제52권7호
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    • pp.475-482
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    • 2019
  • Subseasonal-to-Seasonal (S2S) prediction information which have 2 weeks to 2 months lead time are expected to be used through many parts of industry fields, but utilizability is not reached to expectation because of lower predictability than weather forecast and mid- /long-term forecast. In this study, we used multi-layer perceptron (MLP) which is one of machine learning technique that was built for regression training in order to improve predictability of S2S precipitation data at South Korea through post-processing. Hindcast information of ECMWF was used for MLP training and the original data were compared with trained outputs based on dichotomous forecast technique. As a result, Bias score, accuracy, and Critical Success Index (CSI) of trained output were improved on average by 59.7%, 124.3% and 88.5%, respectively. Probability of detection (POD) score was decreased on average by 9.5% and the reason was analyzed that ECMWF's model excessively predicted precipitation days. In this study, we confirmed that predictability of ECMWF's S2S information can be improved by post-processing using MLP even the predictability of original data was low. The results of this study can be used to increase the capability of S2S information in water resource and agricultural fields.

Numerical Study on the Characteristics of Fluid Flow and Pressure Fluctuation around Human Knuckle in Hydrogymnastics (수중 운동 시 손관절 부위의 유동 및 압력변동 특성에 대한 해석적 연구)

  • Choi, Ji-Hyun;Park, Sung-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제20권6호
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    • pp.390-395
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    • 2019
  • Hydrogymnastics so that sufficient exercise effect can be obtained using the resistance of water has a positive effect on patients who have to receive arthritis or rehabilitation treatment. However, the studies on the effect are insufficient, and the main cause of their effects has not been unclear yet. In this study, in order to identify the main cause of the effects of Hydrogymnastics, conducted Unsteady fluid flow simulation under the same conditions as the actual environment. The analysis model based on real hands, and the pressure fluctuation applied to the knuckle was analyzed by the computational fluid method. During the underwater movement of the hands, Various sizes of vortices were generated between fingers due to skin surface velocity and flow resistance. Pressure of about -500 Pa to +500 Pa is applied by the vortex flow. Also It was confirmed that the positive pressure and the negative pressure were continuously repeated up to maximum + 2000 Pa at the minimum of -2000 Pa at the portion where the direction was changed. Pressure fluctuations with a frequency of 20 Hz to 70 Hz were added continuously for each knuckle. These continuous pressure fluctuations provide a direct massage effect on the knuckles, an It is judged that the blood circulation at the relevant part is positively affected.

A Study on the Management Efficiency Analysis of IT high-growth Corporation: Using DEA (고성장 IT기업에 대한 경영 효율성 분석: 자료포락분석(DEA) 기법을 중심으로)

  • Lee, Ki-Se;Kang, Da-Yeon
    • Journal of Digital Convergence
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    • 제17권7호
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    • pp.27-34
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    • 2019
  • The IT industry has made rapid development and also had an economic impact on other industries Also, since the fourth industrial revolution has begun in recent years ago, so The convergence between IT and other industries is increasing. Therefore, the development of the IT industry will enhance the international competitiveness It will also have a major impact on the nation's economic growth. Therefore, IT firms should be more efficient in their production. so This paper analyzes the efficiency of High-growth IT firms using DEA model. We evaluate the CCR, BBC efficiency and RTS(return to scale) of 12 IT firms. As a result, there were 6 companies with BCC efficiency 1 and 4 companies with 1 CCR efficiency. The scale of profitability was analyzed by IRS as 7 companies and CRS as 5 companies. We also suggest the IT firms which can be benchmarked based on analyzed information. It is expected to provide investors and external stakeholders with very useful information on managerial management efficiency.

Uncertainty Analysis of BAG by GNSS Correction (해저지형 표면자료의 GNSS 보정방법에 따른 불확실도 연구)

  • OH, Che-Young;KIM, HO-Yong;LEE, Yun-Sik;CHOI, Chul-Uong
    • Journal of the Korean Association of Geographic Information Studies
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    • 제22권3호
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    • pp.1-9
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    • 2019
  • In the recent marine sector, the development and standardization regarding S-100, which is the universal hydrographical data model standard for development of marine space information, was progressed, and for the effectiveness of marine chart production work and the multi-purpose use of water level data in S-100, S-102(Bathymetric Surface grid) standard development and various studies of BAG formats combined with water level and uncertainty, property information is being progressed. Since the water level information that is important in the operation of the ship is provided based on S-102, the calibration method of the location information when producing S-102 is an important factor in deciding the water level. In this study, the hydrographical surveying was conducted by piloting the standardized method for the production of S-102 in Korea, and have compared the accuracy of water level information according to the GNSS post treatment calibration method. As a result of comparing the water level in 2 places in the rocky terrain of the study area, the northern water level of Namu-do was shown as DL 0.79~0.83m, the eastern water level of Daeho-do was DL 12.63~12.91m, and the horizontal position errors of the intermittent sunshine water level were confirmed to be within 1m. As a result, the intermittent sunshine water level according to the location calibration method when producing the BAG was confirmed that it was in the available range for a ship's safe voyage. However, the accuracy verification for the location of the ship when conducting hydrographical surveying was judged that there is a need for a various additional study about regional characteristics and environment factor.

Strategies for utilizing Urban Ventilation Corridor considering Local Cold Air in Watershed Areas - A Case Study of Uijeongbu and Gwacheon - (유역의 찬공기 특성을 고려한 도시 바람길 활용 전략 - 경기도 의정부 및 과천 일대를 사례로 -)

  • EUM, Jeong-Hee
    • Journal of the Korean Association of Geographic Information Studies
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    • 제22권2호
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    • pp.133-151
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    • 2019
  • This study aims to analyze cold air characteristics in the watershed areas and to suggest strategies for utilizing them in urban ventilation corridor plans. For this purpose, the Jungnangcheon watershed and Uijeongbu-si in the northern part of Gyeonggi province, and Anyangcheon watershed as well as Yangjaecheon Tancheon watershed and Gwacheon-si in the southern part were selected as study areas. We used KALM (Kaltluftabflussmodell), a cold air simulation model developed in Germany and identified both the cold air flow and the height of cold air layer generated during 6 hours at night. Uijeongbu City is located on the main stream of the Jungnangcheon watershed, and the local cold air from the southern outskirts is an important part of Uijeongbu-si's overall ventilation corridor planning. In addition, the cold air generated in the vicinity of Mt. Sapae flows into the central business district near the city hall and plays a major role in regulating the thermal environment of the city. But, the cold air flows in the eastern part of Uijeongbu-si was not smoothly. The cold air flow generated in the east of Gwanak Mountain and in the west of Cheonggye Mountain was the most active in the northern part of Gwacheon-si. This flow is also a major ventilation corridor in Anyangcheon watershed as well as Yangjaecheon Tancheon watershed. But, the southern part where the cold air flow is not smooth is planed to be developed as 'Gwacheon Knowledge Information Town Public Housing District', so rapid development is expected in the future. Hence, it is suggested that an additional ventilation corridor plan should be established based on the detailed local wind flow analysis.

A Study on Social Media Advertising of Plastic Surgery Using Eye-Tracking (아이트래킹을 활용한 성형외과 소셜 미디어광고의 시선 추적 연구)

  • Son, Jeong-Eun;Jung, Eui-Tay;Paik, Jin-Kyung
    • The Journal of the Korea Contents Association
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    • 제19권7호
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    • pp.1-12
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    • 2019
  • According to a survey on the frequency of access to medical ads by the Korea Press Foundation in 2017, the most commonly exposed ads among adult men and women are advertising about beauty, plasticity and obesity. As of 2011, South Korea had the largest number of cosmetic surgeries in the world, with 131 cosmetic surgeries per 10,000 people. As a result, as many as 1,414 plastic surgery clinics are operating in South Korea, and the number is also on the rise. Although there are various standards for evaluating people's appearance, the desire to pursue a better look is growing day by day. Then, one might wonder what factors influence consumers' choices among the numerous advertisements for plastic surgery clinics. Based on these questions, this study identified the examples of plastic surgery advertisements, analyzed their type, and identified the types of advertisements with the high visual appeal of the advertising consumer through eye tracking experiment. In total, seven eye-tracking tests of plastic surgery social media advertisements were conducted on 10 subjects. The results showed that the commercial model was the biggest factor that caught the attraction and attention of the ad recipient first and that the most focused and long-standing factor was the treatment contents. Therefore, it is important to select proper commercial models for hospital and clinic contents and to specify factual treatment contents when producing social media advertisements for plastic surgeons. We hope these findings will help create online advertising for plastic surgery clinics effectively.

The Effect of College Festival Participants' Experience on Festival Satisfaction, Re-participation and Peer Relation Enhancement: Focusing on College Life Participation (대학축제체험이 축제만족, 재참가의도, 교우관계에 미치는 영향: 대학생활 참여정도를 중심으로)

  • Yang, Soung-Hoon
    • The Journal of the Korea Contents Association
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    • 제19권7호
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    • pp.246-257
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    • 2019
  • This research aimed to verify possibly expanding college festival's performance to ordinary life. College festivals have consolidated student communities and created college culture. Recently, the festivals have been challenged for commercialization such as celebrity concert and company sponsorship. College festival is a text, which is based on ordinary college life and should served a role to restore college life. Pine & Gilmore's experience model was used to find that quality festival experience leads to satisfaction and satisfaction enhance peer relations. More participate school life, the better experience the festival program. Total 195 of questionnaires were administered to college festival participants and coding data were analyzed by regression and t test. Result found that College festival experience significantly affects festival satisfaction(H1), festival satisfaction affect re-participation(H2) and peer relations(H3). High level of school life participation group showed significant differences in festival experience and other variables in compare with low level group(H4). Theoretical /practical significances and research limitation were included.

Spatial Econometrics Analysis of Fire Occurrence According to Type of Facilities (시설물 유형에 따른 화재 발생의 공간 계량 분석)

  • Seo, Min Song;Yoo, Hwan Hee
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • 제37권3호
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    • pp.129-141
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    • 2019
  • In recent years, fast growing cities in Korea are showing signs of being vulnerable to more disasters as their population and facilities increase and intensify. In particular, fire is one of the most common disasters in Korea's cities, along with traffic accidents. Therefore, in this study, we analyze what type of factors affect the fire that threatens urban people. Fire data were acquired for 10 years, from 2007 to 2017, in Jinju, Korea. Spatial distribution pattern of fire occurrence in Jinju was assessed through the spatial autocorrelation analysis. First, spatial autocorrelation analysis was carried out to grasp the spatial distribution pattern of fire occurrence in Jinju city. In addition, correlation and multiple regression analysis were used to confirm spatial dependency and abnormality among factors. Based on this, OLS (Ordinary Least Square) regression analysis was performed using space weighting considering fire location and spatial location of each facility. As a result, First, LISA (Local Indicator of Spatial Association) analysis of the occurrence of fire in Jinju shows that the most central commercial area are fire department, industrial area, and residential area. Second, the OLS regression model was analyzed by applying spatial weighting, focusing on the most derived factors of multiple regression analysis, by integrating population and social variables and physical variables. As a result, the second kind of neighborhood living facility showed the highest correlation with the fire occurrence, followed by the following in the order of single house, sales facility, first type of neighborhood living facility, and number of households. The results of this study are expected to be useful for analyzing the fire occurrence factors of each facility in urban areas and establishing fire safety measures.

The Study for Analysis of Impact Force of Debris Flow According to the Location of Check Dam (사방댐 위치변화에 따른 토석류의 충격력 해석에 관한 연구)

  • Kim, Sung-Duk;Lee, Ho-Jin;Chang, Hyung-Joon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제20권1호
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    • pp.409-418
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    • 2019
  • Debris flows occur in mountainous areas due to heavy rains resulting from climate change and result in disasters in the downstream area. The purpose of this study is to estimate the impact force of a debris flow when a check dam according is installed in various locations in the channel of a highly mountainous area. A Finite Differential Element Method (FDM) model was used to simulate the erosion and deposition based on the equation for the mass conservation and momentum conservation while considering the continuity of the fluid. The peak impact force from the debris flow occurred at 0 to 5 sec and 15 to 20 sec. When the supplied water discharge was increased, greater peak impact force was generated at 16 to 19 sec. This means that when increasing the water supply, the velocity of the debris flow became faster, which results in increased energy of the consolidation between the particles of the water and the sediment made. If a number of check dams were to be set up, it would be necessary to investigate the impact force at each location of the check dam. The results of this study could provide useful information in predicting the impact force of the debris flow and in installing the check dams in appropriate locations.