• Title/Summary/Keyword: production function

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국가혁신시스템의 기능분석 -시스템이론의 접목을 통한 탐색적 개념연구-

  • 임윤철
    • Proceedings of the Technology Innovation Conference
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    • 1996.12a
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    • pp.241-264
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    • 1996
  • This article introduces the five functions of the national innovation system (NIS). As the national innovation system is a kind of social systems in the national level, the five generic functions of open system-production boundary spanning, maintenance, adaptation management functions-are applied to the NIS. The production function is the primary process, which produces innovative products and services of the NIS. The boundary spanning function is the function of procuring the input and disposing the innovation output or aiding in these process. Experienced R&D human resources, R&D funds, technology etc. belong to the input of the NIS. The maintenance function is responsible for the smooth operation and upkeep of the system in terms of various conditions. The adaptive function is to help the system change and adapt, scan the environment for problems, opportunities, and technological developments. It faces outward for the survival of the system from the long-term view. The management function carries out planning and controlling the overall activities for the other four functions in order to run the system. Finally it discuses implications for the diagnosis and the decision making process of S&T policy.

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Estimation of smooth monotone frontier function under stochastic frontier model (확률프런티어 모형하에서 단조증가하는 매끄러운 프런티어 함수 추정)

  • Yoon, Danbi;Noh, Hohsuk
    • The Korean Journal of Applied Statistics
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    • v.30 no.5
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    • pp.665-679
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    • 2017
  • When measuring productive efficiency, often it is necessary to have knowledge of the production frontier function that shows the maximum possible output of production units as a function of inputs. Canonical parametric forms of the frontier function were initially considered under the framework of stochastic frontier model; however, several additional nonparametric methods have been developed over the last decade. Efforts have been recently made to impose shape constraints such as monotonicity and concavity on the non-parametric estimation of the frontier function; however, most existing methods along that direction suffer from unnecessary non-smooth points of the frontier function. In this paper, we propose methods to estimate the smooth frontier function with monotonicity for stochastic frontier models and investigate the effect of imposing a monotonicity constraint into the estimation of the frontier function and the finite dimensional parameters of the model. Simulation studies suggest that imposing the constraint provide better performance to estimate the frontier function, especially when the sample size is small or moderate. However, no apparent gain was observed concerning the estimation of the parameters of the error distribution regardless of sample size.

Effects of acute reducing salt supplementation on cardio-respiratory function, blood pressure and serum nitric oxide production in elite players

  • Kim, Hag-Lyeol;Ueda, Hideo;Son, Yeon-Hee;Lee, Sam-Jun;Kim, In-Cheol
    • Korean Journal of Exercise Nutrition
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    • v.14 no.2
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    • pp.95-101
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    • 2010
  • The purpose of this study was to evaluate changes of body composition, cardio-respiratory function in ventilation threshold (VT) and maximal state exercise, systolic (SBP) and diastolic blood pressure (DBP) and serum nitric oxide (NO) production during acute reducing salt (RS) supplementation in college elite athletes. Variables of cardio-respiratory function during rest, ventilation threshold and maximal exercise was not shown a significantly difference between RS supplementation and non-supplementation, there was shown a significant increase in ventilation threshold time (p<0.05) and exhaustion time (p<0.05) during RS supplement compared to non-supplement. SBP and DBP were not shown a significant difference between RS supplement and non-supplement. This result suggests that acute intake of RS is not increased a blood pressure. Serum NO production was not significant difference in the RS supplement group, but it was shown a significantly increased levels (p<0.01, vs. recovery 30 min.) immediately after maximal exercise in the non-supplement group. This result suggests that acute intake of RS have important role in inhibition of serum NO production during maximal exercise. Conclusively, This study suggest that acute intake of RS was not influence in body composition variables, but it was positive effect in ventilation threshold time, exhaustion time, maintenance of blood pressure and inhibition of serum NO production in maximal treadmill exercise.

The Estimation of Production Cost of Local Public Goods with Environmental Difference (환경요인에 따른 지역공공재 생산비용의 격차 추정)

  • 최영호;박상우
    • Journal of the Korean Regional Science Association
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    • v.12 no.2
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    • pp.21-36
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    • 1996
  • This thesis focused on the extent of the area-by-area gap of the unit production cost that should be taken into account without exception in supply of the local public goods production cost. With the advent of the local autonomy era, what should be considered in the local governmen's production of the local public goods are the government's fiscal capacity and the environmental difference that shows up in accordance with the area's characteristics. Though with the same level of the fiscal capacity, an occurrence of environmental difference will lead inevitably to the different level of actual supply of the local public goods. The method of analysis used in this thesis was first to bring out implicit price, to combine this with induced expenditure function, to separate demand function parameter and cost function parameter, and then to analyzed the impact of environmental variables on the production cost. The environmental variables were set on the basis of the ones that affected expenditure per person of the public goods. The analysis was conducted in distinction of city areas and county areas. The results showed that, in cases of cities, more production cost of the public goods was in presence in urban areas and in areas where there was sluggish development. In other words, distinction could be drawn between areas where there was a large consumption of production cost resulting from poor environmental sparked by slow development and those where additional costs were required due to population concentration caused by a certain level of accomplished development. In the meantime, in cases of county areas, the results were around the same. However, a comparison between city areas and county ones told that overall difference between city areas was not that big in the production cost while that in county areas was large enough. In times ahead, in implementation of grant-in-aid scheme, production cost index for local public goods could be used as it was written in consideration of environmental characteristics of areas concerned.

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Management of small yellow croaker stock in Korean waters based on production value-per-recruit analysis (가입당 생산액 분석에 의한 한국 해역 참조기 Larimichthys polyactis 자원의 관리)

  • Zhang, Chang-Ik;Lee, Eun-Ji;Kang, Hee-Joong
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.50 no.4
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    • pp.467-475
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    • 2014
  • This study was performed to estimate optimum fishing mortality (F) and the age at first capture ($t_c$) for small yellow croaker in Korean waters. We first estimated optimum F and $t_c$ using traditional yield-per-recruit (YPR) analysis, and the results were 0.8/year and 2.5 years old, respectively. However, the individual fish price per unit weight of small yellow croaker in Korea increases dramatically by size. Thus, we developed an alternative method, which is called as production value-per-recruit (PPR) analysis. We developed two types of the PPR analysis, that is, the discrete function and the continuous function method. We estimated optimum F and $t_c$ using the two types of the PPR analysis and compared the results. The optimum F and $t_c$ from the discrete function method, were 0.3/year and 5.0 years old, respectively, while those from the continuous function method were 0.5/year and 3.5 years old, respectively. These PPR estimates were much more conservative for the stock management than the traditional YPR analysis, which can prevent the fish stock from the economic overfishing. As a result, the PPR analysis could be more proper approach for stock assessment in the case that the individual fish price per unit weight increases dramatically by size like small yellow croaker in Korea.

A Model for Production Planning in a Multi-item Production System -Multi-item Parametric Decision Rule- (다품목(多品目) 생산체제(生産體制)의 생산계획(生産計劃)을 위한 모델)

  • Choe, Byeong-Gyu
    • Journal of Korean Institute of Industrial Engineers
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    • v.1 no.2
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    • pp.27-38
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    • 1975
  • This paper explores a quantitative decision-making system for planning production, inventories and work-force in a multi-item production system. The Multi-item Parametric Decision Rule (MPDR) model, which assumes the existence of two types of linear feed-back rules, one for work-force level and one for production rates, is basically an extension of the existing method of Parametric Production Planning (PPP) proposed by C.H. Jones. The MPDR model, however, explicitly considers the effect of manufacturing progress and other factors such as employee turn-over, difference in work-days between month etc., and it also provides decision rules for production rates of individual items. First, the cost relations of the production system are estimated in terms of mathematical functions, and then decision rules for work-force level and production rates of individual items are establised based upon the estimated objective cost function. Finally, a direct search technique is used to find a set of parameters which minimizes the total cost of the objective function over a specified planning horizon, given estimates of future demands and initial values of inventories and work-force level. As a case problem, a hypothetical decision rule is developed for a particular firm (truck assembly factory).

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Alternatives for Strengthening the Function of Free Trade Zone in Gwangyang Bay Area (광양만권 자유무역지역의 기능 강화 방안에 관한 연구)

  • Kim, Hyun-Duk
    • Journal of Navigation and Port Research
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    • v.35 no.6
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    • pp.533-538
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    • 2011
  • Recently, Free Trade Area generally moves toward a complex and total zone carrying out the logistics and production function simultaneously. Nevertheless, Free Trade Area of Gwangyang Bay Area performs a traditional logistics function only without a introduction of production function. Therefore, the purpose of this research is to suggest alternatives for strengthening the function of Free Trade Area of Gwangynag port. The main findings of this research is summarized as followings. First, a complex and total Free Trade Area through enhancing a production function is to be established. Second, for an efficient management & operation of Free Trade Area, a cooperative system establishment between Free Trade Areas and a single operation system is necessary.

A Dynamic Production and Transportation Model with Finite Number of Multiple Transportation Modes (유한 대수의 다종 수송수단을 고려한 동적 생산-수송 모형)

  • Sohn, Kwon-Ik
    • Journal of Industrial Technology
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    • v.29 no.A
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    • pp.183-190
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    • 2009
  • This study deals with the single-product production and transportation model with dynamic demand over finite time horizon, in which the optimal production(order) quantities, transportation modes and the number of each vehicles are determined simultaneously. The finite number of identical vehicles with capacity constraint is given to each mode. Production and transportation costs are assumed to be concave function for generality. For a relevant mathematical model formulated, the theorems and properties are discussed to present the efficient algorithm. A numerical example is solved to illustrate the algorithm developed.

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An Empirical Analysis on the Productivity of Coastal Fishery (연안어업 생산성에 관한 실증연구)

  • Eh, Young-Yang;Song, Dong-Hyo;Hwang, Seon-Jae;Park, Bo-Gyeong
    • The Journal of Fisheries Business Administration
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    • v.51 no.1
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    • pp.19-36
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    • 2020
  • The purpose of this paper is to analyze the productivity of the costal fisheries in Jeonnam Province. In this study, the operational characteristics and Cobb-Douglas production function of coastal fisheries were examined based on a research on the actual condition of costal fisheries (RACF). The statistical analysis of RACF data reveals that Cobb-Douglas production function consists of the three variables: fishing quantity per ton-age, the number of fisherman per ton-age and fishing equipment cost per ton-age. The results of this study show us that the relation and productivity between labor and capital of the operational equipment in the coastal fisheries. If extensive comparable biological and market data become available, analysis model can be widely applied to yield more accurate results.

Defect classification of refrigerant compressor using variance estimation of the transfer function between pressure pulsation and shell acceleration

  • Kim, Yeon-Woo;Jeong, Weui-Bong
    • Smart Structures and Systems
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    • v.25 no.2
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    • pp.255-264
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    • 2020
  • This paper deals with a defect classification technique that considers the structural characteristics of a refrigerant compressor. First, the pressure pulsation of the refrigerant flowing in the suction pipe of a normal compressor was measured at the same time as the acceleration of the shell surface, and then the transfer function between the two signals was estimated. Next, the frequency-weighted acceleration signals of the defect classification target compressors were generated using the estimated transfer function. The estimation of the variance of the transfer function is presented to formulate the frequency-weighted acceleration signals. The estimated frequency-weighted accelerations were applied to defect classification using frequency-domain features. Experiments were performed using commercial compressors to verify the technique. The results confirmed that it is possible to perform an effective defect classification of the refrigerant compressor by the shell surface acceleration of the compressor. The proposed method could make it possible to improve the total inspection performance for compressors in a mass-production line.