• Title/Summary/Keyword: System Production Process

Search Result 3,103, Processing Time 0.031 seconds

A Study on Reverse-water Gas Shift Reaction in Solid Oxide Water Electrolysis Cell-stack for CO2 Reduction (CO2 저감을 위한 고체산화물 수전해 스택의 역수성가스 전환 반응 고찰)

  • SANGKUK KIM;NAMGI JEON;SANGHYEOK LEE;CHIKYU AHN;JIN SOO AHN
    • Journal of Hydrogen and New Energy
    • /
    • v.35 no.2
    • /
    • pp.162-167
    • /
    • 2024
  • Fossil fuels have been main energy source to people. However, enormous amount of CO2 was emitted over the world , resulting in global climate crisis today. Recently, solid oxide electrolyzer cell (SOEC) is getting attention as an effective way for producing H2, a clean energy resource for the future. Also, SOEC could be applicable to reverse water-gas shift reaction process due to its high-temperature operating condition. Here, SOEC system was utilized for both H2 production and CO2 reduction process, allowing product gas composition change by controlling operating conditions.

Development of a Sortie Generation Rate Simulation Using Discrete Event Simulation (이산 사건 시뮬레이션을 이용한 소티 생성률 산출 시뮬레이션 개발)

  • Heechang Yoon;Seungheon Oh;Hyuk Lee;Sunah Jung;Junghoon Chung;Jonghoon Woo
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.61 no.4
    • /
    • pp.208-215
    • /
    • 2024
  • The Sortie Generation Rate (SGR), which measures the number of sorties that an airbase can produce per unit of time, is crucial for assessing operational capacity. However, the unique spatial and environmental constraints on aircraft carriers complicate the direct application of land-based SGR studies to maritime settings. This study introduces a framework for analyzing the Sortie Generation Process (SGP) on aircraft carriers, using discrete event simulation adapted to these constraints. This approach conceptualizes the SGP similar to a logistics and production system, wherein sorties are systematically generated through the operations of the aircraft. The proposed framework defines and implements the necessary simulation functions with the discrete event simulation method for the purpose of SGP analysis. Through a series of experiments, this study demonstrates the framework's effectiveness and its practical applicability to aircraft carrier operations, potentially enhancing sortie generation capabilities in naval aviation.

The process of modernization of Geomundo during Japanese colonial period : focused on social structure (일제강점기 거문도 근대화 과정 -사회구조를 중심으로 -)

  • Park, Min Joung;Park, Soon Ho
    • Journal of the Korean association of regional geographers
    • /
    • v.22 no.1
    • /
    • pp.36-48
    • /
    • 2016
  • This paper analyzed the process of modernization in terms of the social structure in Geomundo. Before modernization, social structure in Geomundo was traditional society by a village unit. A village had community rituals and organization. There were independent parallel spatial structure among villages. In the early Japanese colonial period, 'forced modernization' had been occurred by Japanese immigrants settling in a separate living space. The modernization was transplanted in a new established village and diffused into other villages. In the process of forced modernization, the connection among villages was reinforced, as the result of that modern social organization was emerged, and the characteristics of community rituals had been changed. During modernization indigenization period, advanced fishery technology and distribution system occurred capitalist production system helping to place modern norms in the general daily life. In the late Japanese colonial period, aided organizations from local government and informal organizations reversed the trend of modernization through helping colonial exploitation policy. The spatial structure in Geomundo had become to hierarchical structure with intensified connectivity as the result of extensive spread of community territory. Modernization in Japanese colonial period was 'forced modernization' and could not re-established the community spirits. The community spirit has been broken up by dissolving the existing self regulating and self motivated organization.

  • PDF

A Study on Evaluation of Target Region for the Agricultural Non-point Sources Management (새만금 유역 농업비점오염원 관리를 위한 우선지구 선정연구)

  • Jang, Nam-Jung;Kim, Bo-Guk;Im, Seoung-Hyun;Kim, Tae-Kyun
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.34 no.1
    • /
    • pp.23-31
    • /
    • 2012
  • Measures against non-point sources pollution in Saemangeum watershed should be established to control water quality of Saemangeum lake, because non-point sources pollution discharge portions of BOD (Biological Oxygen Demand) and TP (Total Phosphorous) in the watershed were 68.4 and 61.4%, respectively. In this study, target regions for the non-point sources pollution control were selected to apply BMP (Best Management Practices) for the agricultural area of Saemanguem watershed in terms of TP that caused eutrophication at the lake. Target regions were selected by the NPSI (Non-point source index) that was calculated by the total 12 indexes at the steps of non-point source production, emission and outflow. Weights of the indexes were determined by the watershed management experts oriented AHP (Analytic Hierarchy Process) analysis. The target region was selected at the unit of Korean basic administrative district 'Dong/Li'. At the results of NPSI calculations through the GIS (Geographical Information System) tools, two sets of 5 regions were selected in the Man-kyung River and Dong-gin River. The main reason for the selected target regions was livestock activity in the district. The results of this study can be useful for implementing the reduction projects of agricultural non-point sources pollution to control water quality in Saemangeum lake.

A Study on Development Strategies of the Korean Fisheries Outlook Project based on AHP (AHP 기법을 이용한 우리나라 수산업관측사업의 추진방향에 관한 연구)

  • Nam, Jong-Oh;Nho, Seung-Guk
    • The Journal of Fisheries Business Administration
    • /
    • v.41 no.1
    • /
    • pp.25-52
    • /
    • 2010
  • The purpose of this paper is to suggest major strategies and necessary new projects for the medium- and long-term development of the Korean Fisheries Outlook Project. To suggest the Korean Fisheries Outlook Center with the above purpose, this paper employs Analytic Hierarchy Process analysis based on surveys obtained by special groups related with the KFOP. The survey is broadly composed of two goals; the medium- and long-term development directions and setting up of new furtherance projects. Each goal has upper and lower strategies respectively. The first goal, the medium- and long-term development directions, has four factors as upper strategies. The upper strategies are composed of accuracy, efficiency, timeliness, and political effectiveness of the fisheries outlook information. In addition, each upper strategy has three lower strategies respectively. For example, accuracy of the fisheries outlook information includes strength of data collection function, strength of satellite photography function, and strength of data analysis function. The second goal, setting up of new furtherance projects, has three factors as upper strategies. The upper strategies consist of accuracy promotion of outlook information using high-technique, field expansion of outlook species, and strength of analyzing function on oversea fisheries information. Each upper strategy has three lower strategies respectively. For instant, accuracy promotion of outlook information using high-technique has strength of information analysis function covered from production to consumption, strength of satellite information function, and structure of forecasting model on demand and supply by outlook species. The above upper and lower strategies were analytically drawn out through insightful interviews with special groups such as officials of the government, presidents of the producer and distributor groups, and researchers of the Korea Maritime Institute and other research institutes. As a result of AHP analysis, first, priorities of upper strategies with the medium- and long-term development directions are analyzed as accuracy, timeliness, political effectiveness, and efficiency in order. Also, priorities of all lower strategies reflecting priorities of upper strategies are examined as includes strength of data collection function on the fisheries outlook information, delivery of rapid information on outlook products for all people interested, strength of data analysis function on fisheries outlook information, strength of consumption outlook function on fish products, and strength of early warning system for domestic fish products in order. Second, priorities of upper strategies with the setting up of new furtherance projects are analyzed as accuracy promotion of outlook information using high-technique, field expansion of outlook species, and strength of analysis function on oversea fisheries information in order. In addition, priorities of all lower strategies reflecting priorities of upper strategies are examined as building up of forecasting model on demand and supply by outlook species, strength of information analysis function covering all steps from production to consumption, expansion of consumption outlook for consumers, strength of movement analysis function of oversea farming industry, and outlook expansion of farming species.

The Current Status of Use and the Difference of Awareness by User Groups in the Cheongryongsan Vegetable Garden Park (청룡산 텃밭공원의 이용실태와 이용주체간 의식 차이)

  • Son, Yong-Hoon;Lim, Jung-Eon
    • Journal of Korean Society of Rural Planning
    • /
    • v.20 no.2
    • /
    • pp.71-80
    • /
    • 2014
  • This study intended for Cheongryongsan Community Garden in Gwanak-gu, one of the demonstration places for 'Community Garden' Project recently implemented by the Seoul Government. This study had two major purposes: investigating the current status of the management and usage and identifying its characteristics; investigating users' awareness to consider the construction and operation directions of sustainable community gardens. This study was conducted based on several surveys such as an investigation into the spatial configuration and the management system of parks through a field study, a use survey through a questionnaire survey for vegetable garden users and an awareness survey about the construction direction of gardens direction preferred by users through the analytical hierarchy process (AHP). As a result of a questionnaire survey for vegetable garden users, the usage status was summarized as follows: Considering the common trends in the 2012 and the 2013 user survey, women used Cheongryongsan Vegetable Garden more than men. Over fifties used it most of all users. Users were mostly neighborhood residents. They used to visit there three to five times a week and stayed for about 30 minutes to one hour. Users differently responded to the question related to the order of priority for the use of the garden in the 2012 and the 2013 survey. They had increasingly used it for individuals' production activities more than social exchanges. As a result of making an AHP analysis for general park users, vegetable garden users there were clear differences in the targets which each subject put emphasis on in relation to the construction and operation of vegetable gardens. General park users recognized a vegetable garden as a park where park functions and the functions of the vegetable garden coexisted. On the other hand, vegetable garden users viewed it as a space where they attached importance to the functions of the vegetable garden like an allotment. Last, this study contemplated subjects related to the construction and operation of vegetable gardens which had to be considered in the future. Vegetable gardens tended to be biased as personal hobby places. It was viewed that the main reason was insufficient support activities for vegetable garden education and exchange programs originally planned when vegetable gardens had been constructed. Vegetable garden users recognized vegetable gardens as places for individuals' farming activities like allotments. For the desirable operation of vegetable gardens, it would be necessary to give priority to the park management before the production activities in individuals' vegetable gardens. The important role of the government would be to build the base through the provision of education and opportunities so that a local resident organization could actively participate in the management of a vegetable garden after a vegetable garden was constructed. It would be necessary to make a use survey and an awareness survey for users conducted in this study on a regular basis because the surveys could be important basic data in the decision-making process for the sustainable operations of the vegetable garden.

Economic Restructuring and Regional Disparity after the IMF Crisis in Korea (IMF 경제위기 이후 경제재구조화와 지역격차)

  • Yim, Seok-Hoi
    • Journal of the Korean association of regional geographers
    • /
    • v.8 no.4
    • /
    • pp.513-528
    • /
    • 2002
  • This paper aims to explore the recent economic restructuring and regional disparity after the IMF crisis in Korea in terms of uneven regional development. The so-called IMF crisis brought about changing Korean society and economy greatly. Although the Korean economy has been almost completely recovered from the IMF crisis, some structural problems remain. In particular, regional disparity has been deepening in the process of economic restructuring for overcoming the IMF crisis. While the Seoul metropolitan area including Kyunggi province has recovered from the crisis relatively fast and industrial production in the area has been kept active, the productive activities of local areas such as Pusan, Taegu, Kwanju and Ulsan province have shrunk significantly. On the contrary, the economic situation of Taejun province is not so bad in comparison with other local areas. The recent deepening of regional disparity after the IMF crisis can be seen as a process of economic restructuring to overcome the crisis. However, it is necessary to point out that production system has already been gradually transformed from Fordism toward post-Fordism since the early 1990s. In this context I argue that the IMF crisis, as an accelerating trigger of such spatial reconfiguration, has deepen regional disparity.

  • PDF

An Evaluation Scheme on Feasibility in Public Sector for 3D Geo-Spatial Information - Focusing on Production of Digital Mapping (3차원 공간정보의 공공부문 사업성 평가 방안 - 2차원 수치지도 제작 업무를 대상으로)

  • Joo, Yong Jin;Kim, Kang Soo;Hahm, Chang Hahk
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.20 no.3
    • /
    • pp.73-82
    • /
    • 2012
  • In order to carry out efficient investment and successful business in national geo-spatial industry, economic assessment on the field of 3D geo-information has recently emerged as a serious issue. Therefore, this study is intended to offer cost-effective evaluation scheme which are proper for 3D geo-spatial information, especially focusing on development of orthophoto and DEM. The study is organized as follows. The first section clarifies preliminary rules for feasibility by defining target work and category in order to estimate benefit. Then, this paper will be limited to consideration of production of digital mapping for target business which is expected to create high value and its benefit from cost reduction is suggested. Drawing from the AHP(Analytic Hierarchy Process) methods, this study comprehensively described final result and implication to examine business value. Consequently, this study can suggest economical evaluation methods on 3D geo-spatial information industry, which takes up a considerable part of immaterial benefit and has difficulties in economic assessment and estimation. preventing a variety of errors in system operation in advance.

A Study on the Intelligent Quick Response System for Fast Fashion(IQRS-FF) (패스트 패션을 위한 지능형 신속대응시스템(IQRS-FF)에 관한 연구)

  • Park, Hyun-Sung;Park, Kwang-Ho
    • Journal of Intelligence and Information Systems
    • /
    • v.16 no.3
    • /
    • pp.163-179
    • /
    • 2010
  • Recentlythe concept of fast fashion is drawing attention as customer needs are diversified and supply lead time is getting shorter in fashion industry. It is emphasized as one of the critical success factors in the fashion industry how quickly and efficiently to satisfy the customer needs as the competition has intensified. Because the fast fashion is inherently susceptible to trend, it is very important for fashion retailers to make quick decisions regarding items to launch, quantity based on demand prediction, and the time to respond. Also the planning decisions must be executed through the business processes of procurement, production, and logistics in real time. In order to adapt to this trend, the fashion industry urgently needs supports from intelligent quick response(QR) system. However, the traditional functions of QR systems have not been able to completely satisfy such demands of the fast fashion industry. This paper proposes an intelligent quick response system for the fast fashion(IQRS-FF). Presented are models for QR process, QR principles and execution, and QR quantity and timing computation. IQRS-FF models support the decision makers by providing useful information with automated and rule-based algorithms. If the predefined conditions of a rule are satisfied, the actions defined in the rule are automatically taken or informed to the decision makers. In IQRS-FF, QRdecisions are made in two stages: pre-season and in-season. In pre-season, firstly master demand prediction is performed based on the macro level analysis such as local and global economy, fashion trends and competitors. The prediction proceeds to the master production and procurement planning. Checking availability and delivery of materials for production, decision makers must make reservations or request procurements. For the outsourcing materials, they must check the availability and capacity of partners. By the master plans, the performance of the QR during the in-season is greatly enhanced and the decision to select the QR items is made fully considering the availability of materials in warehouse as well as partners' capacity. During in-season, the decision makers must find the right time to QR as the actual sales occur in stores. Then they are to decide items to QRbased not only on the qualitative criteria such as opinions from sales persons but also on the quantitative criteria such as sales volume, the recent sales trend, inventory level, the remaining period, the forecast for the remaining period, and competitors' performance. To calculate QR quantity in IQRS-FF, two calculation methods are designed: QR Index based calculation and attribute similarity based calculation using demographic cluster. In the early period of a new season, the attribute similarity based QR amount calculation is better used because there are not enough historical sales data. By analyzing sales trends of the categories or items that have similar attributes, QR quantity can be computed. On the other hand, in case of having enough information to analyze the sales trends or forecasting, the QR Index based calculation method can be used. Having defined the models for decision making for QR, we design KPIs(Key Performance Indicators) to test the reliability of the models in critical decision makings: the difference of sales volumebetween QR items and non-QR items; the accuracy rate of QR the lead-time spent on QR decision-making. To verify the effectiveness and practicality of the proposed models, a case study has been performed for a representative fashion company which recently developed and launched the IQRS-FF. The case study shows that the average sales rateof QR items increased by 15%, the differences in sales rate between QR items and non-QR items increased by 10%, the QR accuracy was 70%, the lead time for QR dramatically decreased from 120 hours to 8 hours.

Evaluation for the simultaneous Removal of Organic Matters and Nutrients by the RBC and tapered Aeration Processes with Bacillus sp. for the high Strength of Dairy Wastewater (바실러스 미생물을 이용한 고농도 유가공 폐수처리에 있어서 유기물질과 영양염류의 동시제거에 대한 평가)

  • Lee, Sang-Ho
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.24 no.2
    • /
    • pp.195-202
    • /
    • 2010
  • The evaluation of organic matters and nutrients removal was investigated for the synthetic wastewater and the high strength of dairy wastewater. Two different systems were performed for this research. System A composing of a single RBC with tapered aeration was fed with the synthetic wastewater for 74 days with 173L/day of influent, 200% of internal return and 100% of sludge return for the period 1 and 2. The feed conditions were maintained 346L/day of influent, 50% of internal return and sludge return for the period 3. The dairy wastewater was introduced to evaluate treatment efficiency for system B composing of dual RBCs and tapered aeration tanks for 50 days of experimental run time, in which hydraulic rates were maintained at the constant ratios of 346L/day, 50% of internal return and 50% of sludge return. The spiral string media made of nylon fibre was attached by Bacillus sp. in RBC for both systems. The specific area of string media was $1.4m^2$/m and biomass was maintained at the concentrations of 23g/m. The synthetic wastewater was supplied by 1,800mg/L of glucose, 500mg/L of $NH_4Cl$, and 500mg/L of $KH_2PO_4$ to system A. The dairy wastewater was supplied to system B from dairy production plant. The average influent concentrations were 1,334mg/L of BOD, 2,014mg/L of CODcr, 160mg/L of T-N, and 12mg/L of T-P in system A. The average influent concentrations of parameters were 1,006 mg/L for BOD, 1,875mg/L for $COD_{cr}$, 51.6mg/L for T-N and 8.9mg/L for T-P in system B. Results indicated that removal efficiencies of BOD and $COD_{cr}$ were more than 90% however, the removal efficiency of T-N was 87%, and that of T-P was 82% for system A. Removal efficiencies were 98.5% of BOD, 91.3% of nitrogen and 89% of phosphorus for system B. The removal efficiencies of organic matters, T-N and T-P were higher in system B than in system A. The effluent quality issued by the stringent national legislations for the discharge of the high strength of dairy products wastewater can be improved using sequential RBCsand tapered aeration reactors rather than a single RBC and tapered aeration reactors with Bacillus sp.