• 제목/요약/키워드: Demand-Supply Model

검색결과 804건 처리시간 0.025초

발전기 출력특성을 고려한 최적전원구성 연구 (A Study of Optimal Fuel-Mix Considering Power Generation Operation)

  • 정영범;김길신;박창호;윤용범
    • 조명전기설비학회논문지
    • /
    • 제25권10호
    • /
    • pp.28-37
    • /
    • 2011
  • Though Korea has introduced CBP(Cost Based pool) power trading system since 2001, long-term Generation system planning has been executed by government for Cost minimization every 2 years. Until currently the model which is used for Generation system planning and best-mix only considers cost minimization and total yearly or quarterly electricity demand every year. In a view point of one day power supply operation, technical characteristics, like the ramp up/down rate of total generation system, minimum up/down time and GFRQ(Governor Free Response Quantity), are very important. this paper analyzes Optimal Fuel-Mix for 2022 Korea generation system satisfying these constraints of each fuel type and considering pump storage plants, construction cost and $CO_2$ emission charge Using MILP(Mixed Integer Linear Programming) method. Also the sensitivity analysis which follows in future power industry environmental change accomplished.

모성보호법 개정과 가임기 여성의 노동시장 성과 (Changes in Korean Maternity Protection Law and Labor Market Outcomes for Young Women)

  • 김인경
    • 노동경제논집
    • /
    • 제33권3호
    • /
    • pp.47-88
    • /
    • 2010
  • 정부는 2001년 산전후휴가 기간 확대와 산전후휴가와 육아휴직 기간 동안의 보조금 지급을 골자로 하는 모성보호법 개정을 단행하였다. 본 연구는 삼중차감기법을 통해 가임기 여성을 위한 이러한 추가 혜택이 가임기 여성의 고용과 시간당 임금에 미친 영향을 분석한다. 젊은 남성, 나이든 여성, 나이든 남성을 통제집단으로 간주하였을 때, 모성보호법 개정으로 인한 가임기 여성의 고용과 시간당 임금 변화는 없었다. 이는 모성보호법 개정이 가임기 여성의 노동공급과 기업의 가임기 여성에 대한 노동수요에 어떠한 변화도 초래하지 않았음을 의미한다.

  • PDF

항만물류 전문인력 양성을 위한 중등교육과정의 우선순위 도출 (Identifying Priority of Subjects for Training Port Logistics Professionals in Secondary Education)

  • 이창훈;강다연;장명희
    • 한국항해항만학회지
    • /
    • 제35권10호
    • /
    • pp.837-846
    • /
    • 2011
  • 항만물류 전문인력을 양성하기 위한 교육은 항만물류분야의 영역과 그 범위가 매우 광범위하여 국가와 기업이 요구하는 능력을 갖춘 인력을 양성하기란 현실적으로 한계를 보이고 있다. 본 연구는 항만물류 전문인력 양성을 위한 중등교육에 필요한 중요 교과목을 도출하기 위해서 인력 수요 및 공급에 대한 현황 및 예측치를 살펴보고, 국내의 선행연구를 바탕으로 평가모형을 구축하여 교과목의 우선순위를 제시함으로써 의사결정의 판단근거를 제공하는데 목적이 있다.

Fiber Mat 의 Sand Mat 대체가능성평가를 위한 실험적 연구 (A Study on the experimental estimation of substitutability of Fiber Mat for Sand Mat)

  • 이송;정용은
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
    • /
    • pp.280-285
    • /
    • 2005
  • At present, there are several problems related with sand mat which is used as a way to accelerate consolidation settlement, act like an underground drainage layer and increase trafficability simultaneously. First of all, the unbalance oft he demand and supply of sand is the one of the biggest problems, which makes not only price advance of sand but also delays a term of total construction work. Secondly, the damage of ecosystem and scenery is triggered by thoughtless sand dredging or mining. So, the need that the sand for sand mat should be replaced with a new environmental friendly material has been increased. Fiber mat may be one of the proper materials that suits the need. Therefore, we intended to compare the drainage properties of sand mat with those of fiber mat by experimental model tests. On the basis of the test results, fiber mat took shorter period of consolidation than sand mat and it's amount of settlement showed a little bit bigger than the other. In conclusion, the substitutability of fiber mat for sand mat could be placed highly in view of drainage efficiency. Furthermore, when Fiber mat is used, it has an advantage that spoil soil of the construction site or nearby site can be used for the purpose of increasing trafficability in addition to a role of drainage layer.

  • PDF

패션 산업에서의 친환경 디자인 (Design for Environment within Fashion Industry)

  • 장남경;김윤정;주잔나
    • 복식문화연구
    • /
    • 제15권6호
    • /
    • pp.952-964
    • /
    • 2007
  • This study is about the design for environment which is central social interest in recent days. This study focused on both experimental designs which convey meanings and practical designs which can be produced within the fashion industry and then influence on the wide range of consumer, human and surrounding environment. The purposes of this study are to categorize national and global fashion designs for environment, to analyze data based on the fashion pipeline from planning to discard, to suggest systematic actions, and to establish fashion design for environment model. Through these processes, this study helps in making fashion designs for environment more understandable, and demonstrates one future direction for using environment as fashion industry's innovative strategy. This study attempts to create business and at the same time suggests design actions based on social belief. The results of this study are following. Fashion designs for environment were categorized by organic fabric, new-to-the-world fabric, reduce, multi-function, reproduce, order-made, recycle, and reuse. The results show that fashion designs for environment have been implemented throughout the fashion pipeline, and applied the concepts of design for environment including green, sustainable slow, and natural design principles. Furthermore, labelling and service from supply side, green purchasing from demand side, and integration from both sides are suggested as company's and society's systematic actions.

  • PDF

A Prediction of Nutrition Water for Strawberry Production using Linear Regression

  • Venkatesan, Saravanakumar;Sathishkumar, VE;Park, Jangwoo;Shin, Changsun;Cho, Yongyun
    • International journal of advanced smart convergence
    • /
    • 제9권1호
    • /
    • pp.132-140
    • /
    • 2020
  • It is very important to use appropriate nutrition water for crop growth in hydroponic farming facilities. However, in many cases, the supply of nutrition water is not designed with a precise plan, but is performed in a conventional manner. We proposes a forecasting technique for nutrition water requirements based on a data analysis for optimal strawberry production. To do this, the proposed forecasting technique uses linear regression for correlating strawberry production, soil condition, and environmental parameters with nutrition water demand for the actual two-stage strawberry production soil. Also, it includes predicting the optimal amount of nutrition water requires according to the heterogeneous cultivation environment and variety by comparing the amount of nutrition water needed for the growth and production of different kinds of strawberries. We suggested study uses two types of section beds that are compared to find out the best section bed production of strawberry growth. The dataset includes 233 samples collected from a real strawberry greenhouse, and the four predicted variables consist of the total amounts of nutrition water, average temperature, humidity, and CO2 in the greenhouse.

Metabolic Analysis of Poly(3-Hydroxybutyrate) Production by Recombinant Escherichia coli

  • WONG, HENG HO;RICHARD J. VAN WEGEN;JONG-IL CHOI;SANG YUP LEE
    • Journal of Microbiology and Biotechnology
    • /
    • 제9권5호
    • /
    • pp.593-603
    • /
    • 1999
  • Poly(3-hydroxybutyrate) (PHB) production by fermentation was examined under both restricted- and ample-oxygen supply conditions in a single fed-batch fermentation. Recombinant Escherichia coli transformed with the PHB production plasmid pSYLl07 was grown to reach high cell density (227 g/l dry cell weight) with a high PHB content (78% of dry cell weight), using a glucose-based minimal medium. A simple flux model containing 12 fluxes was developed and applied to the fermentation data. A superior closure (95%) of the carbon mass balance was achieved. When the data were put into use, the results demonstrated a surprisingly large excretion of formate and lactate. Even though periods of severe oxygen limitation coincided with rapid acetate and lactate excretion, PHB productivity and carbon utilization efficiency were not significantly impaired. These results are very positive in reducing oxygen demand in an industrial PHA fermentation without sacrificing its PHA productivity, thereby reducing overall production costs.

  • PDF

Impacts of the Real Effective Exchange Rate and the Government Deficit on Aggregate Output in Australia

  • Hsing, Yu
    • The Journal of Asian Finance, Economics and Business
    • /
    • 제4권1호
    • /
    • pp.19-23
    • /
    • 2017
  • Based on a simultaneous-equation model consisting of aggregate demand and short-run aggregate supply, this paper estimates a reduced-form equation specifying that the equilibrium real GDP is a function of the real effective exchange rate, the government deficit as a percent of GDP, the real interest rate, foreign income, labor productivity, the real oil price, the expected inflation rate, and the interactive and intercept binary variables accounting for a potential change in the slope of the real effective exchange rate and shift in the intercept. Applying the exponential GARCH technique, it finds that aggregate output in Australia has a positive relationship with the real effective exchange rate during 2003.Q3 - 2013.Q2, the government deficit as a percent of GDP, U.S. real GDP, labor productivity and the real oil price and a negative relationship with the real effective exchange rate during 2013.Q3 - 2016.Q1, the real lending rate and the expected inflation rate. These results suggest that real appreciation was expansionary before 2013.Q3 whereas real depreciation was expansionary after 2013.Q2 and that more government deficit as a percent of GDP would be helpful to stimulate the economy. Hence, the impact of real appreciation or real depreciation on real GDP may change overtime.

풀흐름라인에서 변동성전파원리에 대한 증명 : 존재와 측정 (Proof of the Variability Propagation Principle in a Pull Serial Line : Existence and Measurement)

  • 최상웅
    • 한국경영과학회지
    • /
    • 제27권4호
    • /
    • pp.185-205
    • /
    • 2002
  • In this study, we consider infinite supply of raw materials and backlogged demands as given two boundary conditions. And we need not make any specific assumptions about the inter-arrival of external demand and service time distributions. Under these situations, the ultimate objective of this study is to prove the variability propagation principle in a pull serial line and is to measure it in terms of the first two moments of the inter-departure process subject to number of cards in each cell. Two preparations are required to achieve this objective : The one is to derive a true lower bound of variance of the inter-departure process. The other is to establish a constrained discrete minimax problem for the no backorder (backlogging) probabilities in each cell. We may get some fundamental results necessary to a completion for the proof through the necessary and sufficient conditions for existence of optimal solution of a constrained discrete minimax problem and the implicit function theorem. finally, we propose a numeric model to measure the variability propagation principle. Numeric examples show the validity and applicability of our study.

물류혁신을 위한 자재통합공동물류 시행에 관한 연구(A사 물류시스템 개선사례를 중심으로) (A Study of Trials on Material Integration Pool System for Logistics Rationalization - Basing on the Improvement a precedent about Logistics System of 'A' Enterprise -)

  • 원유존;강경식
    • 대한안전경영과학회:학술대회논문집
    • /
    • 대한안전경영과학회 2006년도 추계공동학술대회
    • /
    • pp.373-383
    • /
    • 2006
  • Logistics is one of the most important factors to manage a stream of materials in economic environment. Establishing effective logistics system needs to consider some constraints which are fluctuation of materials volume, a long distance between makers and consumers, one way logistics and small quantity batch production. It is estimated that Unit Load System should be a powerful method to cope with those problems. It helps to realize the key issues which are Standardization and Logistics Pool System The Material Unification of Logistics System is able to participate in all kinds of industries including manufacturing, distribution and logistics. This system has some merits which are a long distance transportation cost down, product recovery, and treatment in the unbalance of demand and supply caused by unstable materials volume. Four strategies of Material Logistics Model are Packing Rationalization, Logistics Pool System, JIT System application and establishing effective infrastructure. The Material Unification Of Logistics System based on Unit Load System achieves efficiency of logistics and largely decreases moving cost.

  • PDF