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Experimental Test Results of Nine Scheduling Operational Modes of PV and Battery Hybrid System for the Development of Automatic Control Algorithm for Continual Operation without being shut-downed (태양광 배터리 Hybrid 전력공급시스템 9가지 운전 모드 시험결과 및 무고장 연속 운전을 위한 자동제어 알고리즘 개발)

  • Song, Taek Ho;Yang, Seung Kwon;Kim, Minjeong
    • KEPCO Journal on Electric Power and Energy
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    • v.5 no.1
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    • pp.25-32
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    • 2019
  • K-BEMS System was introduced to reduce peak load and to save total energy of the 200 buildings that KEPCO headquarter and branch offices use. And K-BEMS system is composed of PV, battery, and hybrid PCS. KEPCO research institute has carried out this K-BEMS research project for 3 years since January 2016. In this paper, the results of the project are shown. 9 modes of test results of K-BEMS system and are operational problems were analyzed. And measures to cure the trouble are also suggested. Batteries are operated more than 20% of SOC, and less than 20% of SOC battery protection switches are automatically shutting down the system and the system no longer respond to EMS, ending the supply of PV, and so therefore to continue the PV power supply it was turn out to be necessary that the EMS should automatically change its policy to change PV only supply mode automatically when the Battery Switch automatically operated. To operate the system continuously and automatically, it is necessary to modify the minimum operational SOC value, and in addition to that the EMS computer must remember the last shut-down SOC and Voltage which interrupted the system and add some margin to reflect the measurement error in the system.

Enhanced Strobilus Production and Metabolic Alterations in Larix kaempferi by Stem Girdling (환상박피 처리에 의한 일본잎갈나무의 착과유도 효과와 대사물질의 변화)

  • Lee, Wi Young;Park, Eung-Jun;Kang, Jin Taek;Ahn, Jin-Kwon
    • Journal of Korean Society of Forest Science
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    • v.100 no.3
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    • pp.367-373
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    • 2011
  • The demand for Japanese larch (Larix kaempferi) seeds has increased in Korea but their supply has been limited due to sporadic natural seed production. To enhance seed production, stem girdling was applied to 42-yearold Japanese larches, resulting in remarkable enhancement of strobilus production in terms of the rate of strobilusbearing tree and the number of strobilus per tree. Metabolic alterations in the girdled and the control trees were interrogated through GC/MS analysis. In the girdled tree, the contents of 14 individual metabolites including polar and non-polar compounds were significantly increased compared to the control. In the cambium and phloem tissues of girdled trees, the contents of pimaric acid, phosphoric acid, sucrose, and two different unknown compounds were enhanced, while the levels of malic acid, inositol, two different disaccharide, 11-trans-Octadecenoic acid and 4 different unknown compounds were decreased compared to the control. The girdled trees showed to be contained significantly higher amount of total nitrogen in the cambium and phloem tissues than that of control trees. Although the role of individual metabolites on enhanced strobilus production remains unclear, the approach presented in this study might provide useful information in elucidating metabolic network modulation induced by girdling and will be further applied for enhanced strobilus production in Japanese larch trees.

A Study on the Development of Topographical Variables and Algorithm for Mountain Classification (산지 경계 추출을 위한 지형학적 변수 선정과 알고리즘 개발)

  • Choi, Jungsun;Jang, Hyo Jin;Shim, Woo Jin;An, Yoosoon;Shin, Hyeshop;Lee, Seung-Jin;Park, Soo Jin
    • Journal of The Geomorphological Association of Korea
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    • v.25 no.3
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    • pp.1-18
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    • 2018
  • In Korea, 64% of the land is known as mountain area, but the definition and classification standard of mountain are not clear. Demand for utilization and development of mountain area is increasing. In this situation, the unclear definition and scope of the mountain area can lead to the destruction of the mountain and the increase of disasters due to indiscreet permission of forestland use conversion. Therefore, this study analyzed the variables and criteria that can extract the mountain boundaries through the questionnaire survey and the terrain analysis. We developed a mountain boundary extraction algorithm that can classify topographic mountain by using selected variables. As a result, 72.1% of the total land was analyzed as mountain area. For the three catchment areas with different mountain area ratio, we compared the results with the existing data such as forestland map and cadastral map. We confirmed the differences in boundary and distribution of mountain. In a catchment area with predominantly mountainous area, the algorithmbased mountain classification results were judged to be wider than the mountain or forest of the two maps. On the other hand, in the basin where the non-mountainous region predominated, algorithm-based results yielded a lower mountain area ratio than the other two maps. In the two maps, we was able to confirm the distribution of fragmented mountains. However, these areas were classified as non-mountain areas in algorithm-based results. We concluded that this result occurred because of the algorithm, so it is necessary to refine and elaborate the algorithm afterward. Nevertheless, this algorithm can analyze the topographic variables and the optimal value by watershed that can distinguish the mountain area. The results of this study are significant in that the mountain boundaries were extracted considering the characteristics of different mountain topography by region. This study will help establish policies for stable mountain management.

Comparison of carcass and meat quality traits between lean and fat Pekin ducks

  • Ding, Si-Ran;Li, Guang-Sheng;Chen, Si-Rui;Zhu, Feng;Hao, Jin-Ping;Yang, Fang-Xi;Hou, Zhuo-Cheng
    • Animal Bioscience
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    • v.34 no.7
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    • pp.1193-1201
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    • 2021
  • Objective: According to market demand, meat duck breeding mainly includes 2 breeding directions: lean Pekin duck (LPD) and fat Pekin duck (FPD). The aim of the present study was to compare carcass and meat quality traits between 2 strains, and to provide basic data for guidelines of processing and meat quality improvement. Methods: A total of 62 female Pekin ducks (32 LPDs and 30 FPDs) were slaughtered at the age of 42 days. The live body weight and carcass traits were measured and calculated. Physical properties of breast muscle were determined by texture analyzer and muscle fibers were measured by paraffin sections. The content of inosine monophosphate (IMP), intramuscular fat (IMF) and fatty acids composition were measured by high-performance liquid chromatography, Soxhlet extraction method and automated gas chromatography respectively. Results: The results showed that the bodyweight of LPDs was higher than that of FPDs. FPDs were significantly higher than LPDs in subcutaneous fat thickness, subcutaneous fat weight, subcutaneous fat percentage, abdominal fat percentage and abdominal fat shear force (p<0.01). LPDs were significantly higher than FPDs in breast muscle thickness, breast muscle weight, breast muscle rate and breast muscle shear force (p<0.01). The muscle fiber average area and fiber diameter of LPDs were significantly higher than those of FPDs (p<0.01). The muscle fiber density of LPDs was significantly lower than that of FPDs (p<0.01). The IMF of LPDs in the breast muscle was significantly higher than that in the FPDs (p<0.01). There was no significant difference between the 2 strains in IMP content (p>0.05). The polyunsaturated fatty acid content of LPDs was significantly higher than that of FPDs (p<0.01), and FPDs had higher saturated fatty acid and monounsaturated fatty acid levels (p<0.05). Conclusion: Long-term breeding work resulted in vast differences between the two strains Pekin ducks. This study provides a reference for differences between LPD and FPD that manifest as a result of long-term selection.

Knowledge and Educational Needs Related to COVID-19 Infection Control among 119 Paramedics (119구급대원의 COVID-19감염관리에 대한 지식 및 교육 요구도)

  • Park, Jeong-Hee;Lee, Mi-Hyang;Yoon, Byoung-Gil
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.3
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    • pp.65-73
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    • 2021
  • This study aimed to provide the basic data for the development of a simulation training program for new infectious diseases by analyzing the knowledge and educational needs of 119 paramedics regarding COVID-19 infection control. Data was obtained through a structured questionnaire survey of 186 paramedics from November 15th to 30th 2020. The study showed that 98 of the 119 paramedic subjects (52.7%) had not been educated regarding COVID-19. The knowledge level was 18.21±1.98 out of 25 points, with environmental control securing the lowest correct answers. The highest need for education was in the areas of prevention of transmission and spread, and employee safety control. The total average for educational needs was 3.81±.28 (4 point scale) with the highest educational need in the area of prevention of the spread and dispersion of the disease and employee safety management. There was a statistically significant difference in the knowledge of the general characteristics according to gender (t=-1.999, p=.047) and the educational demand was related to career (t=-1.999, p=.047) and, education levels (t=2.336, p=.021). Accordingly, it is necessary to plan a new infectious disease simulation education program that addresses the low-scoring areas and items with high educational needs which include the propagation path and spread prevention, environmental management, and employee safety management as per the findings of this study.

A Study on Status and Necessity of the Curriculum for the Department of Libraries and Information Sciences in Korea (문헌정보학 교과과정에 대한 현황조사 및 인식조사 연구)

  • Hong, Hyun-Jin;Noh, Younghee;Kim, Dongseok
    • Journal of the Korean Society for Library and Information Science
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    • v.55 no.1
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    • pp.5-36
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    • 2021
  • This study attempted to present the direction of development of the curriculum of Library & Information Science by investigating and analyzing the current status of the curriculum of Library & Information Science in Korea and the perception of the necessity of each major subject. To this end, the curriculum of the Department of Library and Information Sciences nationwide was thoroughly investigated. Based on the subjects, a questionnaire survey was conducted for all professors of the Department of Library and Information Science on the degree of consent for required and elective subjects. As a result, first, the total number of courses opened in the Department of Library and Information Science has recently decreased. It was confirmed that the proportion of the required subjects and basic subjects decreased, and the proportion of elective subjects increased. Second, it was found that the importance and weight of informatics are constantly increasing, and there is a high demand for new subjects such as big data, programming, and data analysis. Third, the proportion of library management in all subjects is decreasing, but the necessity of detailed subjects is highly recognized. Fourth, it was confirmed that the proportion of bibliography was gradually decreasing. Fifth, although records management was not a required major subject, its weight increased as an elective subject, while language subjects showed almost no awareness of the necessity.

Status of Groundwater Potential Mapping Research Using GIS and Machine Learning (GIS와 기계학습을 이용한 지하수 가능성도 작성 연구 현황)

  • Lee, Saro;Fetemeh, Rezaie
    • Korean Journal of Remote Sensing
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    • v.36 no.6_1
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    • pp.1277-1290
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    • 2020
  • Water resources which is formed of surface and groundwater, are considered as one of the pivotal natural resources worldwide. Since last century, the rapid population growth as well as accelerated industrialization and explosive urbanization lead to boost demand for groundwater for domestic, industrial and agricultural use. In fact, better management of groundwater can play crucial role in sustainable development; therefore, determining accurate location of groundwater based groundwater potential mapping is indispensable. In recent years, integration of machine learning techniques, Geographical Information System (GIS) and Remote Sensing (RS) are popular and effective methods employed for groundwater potential mapping. For determining the status of the integrated approach, a systematic review of 94 directly relevant papers were carried out over the six previous years (2015-2020). According to the literature review, the number of studies published annually increased rapidly over time. The total study area spanned 15 countries, and 85.1% of studies focused on Iran, India, China, South Korea, and Iraq. 20 variables were found to be frequently involved in groundwater potential investigations, of which 9 factors are almost always present namely slope, lithology (geology), land use/land cover (LU/LC), drainage/river density, altitude (elevation), topographic wetness index (TWI), distance from river, rainfall, and aspect. The data integration was carried random forest, support vector machine and boost regression tree among the machine learning techniques. Our study shows that for optimal results, groundwater mapping must be used as a tool to complement field work, rather than a low-cost substitute. Consequently, more study should be conducted to enhance the generalization and precision of groundwater potential map.

Analysis and Reproduction of Fragrance Components of Lavandula Angustifolia Flower and Essential Oil (라벤더 꽃과 에센셜 오일의 향기 성분 분석 및 재현)

  • Ko, Eun sung;Kim, Hyung mook;Kwak, Byeong mun;Lee, Mi Gi;Bin, Bum ho
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.47 no.2
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    • pp.93-98
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    • 2021
  • This study aims to find a discriminatory way that can lower the dependence on imports of aroma essential oils and increase the value of herb plants that are growing in domestic demand and cultivation. To this end, through a study that analyzes and reproduces fragrance components without damaging the original material of domestically grown lavender flowers using the SPME method, we are trying to confirm the difference in fragrance composition from lavender essential oil and find the fragrance originality of domestically grown herb plants. A total of 38 kinds of lavender essential oils and 27 kinds of lavender flowers were analyzed as fragrance ingredients, Among them, the common ingredients were myrcene, d-limonene, 1,8-cineol, ocimene, p-cymene, α-terpinolene, camphor, linalool, linalyl acetate, bornyl acetate, 4-terpineol, and a-terpineol. In addition, among the fragrance components of the two samples, it was confirmed that the type and content of allergens of domestically cultivated lanvender flowers were low. As a result of the sensuality evaluation of 15 panels, domestic cultivated lavender flower reproduction scent was higher in favor of lavender essential oil, which has been used in the industry until now. It is also believed that lavender fragrance, which lowers the content of allergy-causing ingredients, can expand industrialization.

The Show up Time in the Development of the Korean Pilots Fatigue Management Program (한국형 운항승무원 피로관리 프로그램의 출두시간에 관한 연구)

  • Lee, Seungyoung;Chung, Seung Sup;Kim, Hyeon Deok
    • Journal of Advanced Navigation Technology
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    • v.25 no.4
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    • pp.280-285
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    • 2021
  • The significance of pilots' fatigue and the attributed risk management had continuously increased over time as the airline industry expanded. Research and legislation efforts associated with pilot fatigue are being taking place actively all over the world. In the developed world such as the United States and European Union etc., the airline pilot fatigue is already being managed by considering the show up time, the number of take offs and landings made, resting period, jet lag etc., when computing flight duty time. In Korea, the flight duty time is only limited by the total number of hours per given period regardless of the flight conditions and environment. Such lack of regulation demand development of a fatigue management program. According to the survey taken from the airline pilots in Korea, it has been found that acquiring foreign policies directly may in turn, increase the risk of fatigue. This research suggest future studies regarding fatigue management program adapted exclusively to Korean domestic flight environment and culture.

A Survey on the Consumer Preferences for Improving Retort Food Packaging of Samgyetang on Domestic Market in Korea (국내 레토르트 삼계탕 제품의 포장 개선을 위한 소비자 기호도 조사)

  • Lee, Myungho;Kim, Minhwi;Lee, Youn Suk
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.27 no.3
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    • pp.129-139
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    • 2021
  • We studied the consumer preference for the packaging of "Samgyetang" retort product in order to improve its function and design. A total of 319 eligible respondents (male 175, female 144) were surveyed with a questionnaire asking on the general characteristics for the preference of the packaging function, type of retort package, packaging design, convenience, cooking method of retort product and characteristics of "Samgyetang" retort product. The collected data was analyzed using a chi-square (X2) statistical test in SPSS program. The results showed that the retort packages with opacity and microwaveable types were preferred. Also, most respondents expressed that it needs to be improved for cooking convenience. Another question results showed that the consumers are considering the taste and cost of a product more important than the brand of its product when purchasing. Based on the results of the questionnaire, the study suggested that many consumers want the convenience of packaging and product protection for high value added product. The results help to provide consumer's demand for packaging development and to provide the greatest advantages in terms of production and marketability of "Samgyetang" retort product.