• Title/Summary/Keyword: G(E)-function

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Theoretical Considerations on Fisheries Resource Management and Public Choice (어업자원 이용관리와 공공선택에 관한 이론적 고찰)

  • 박성쾌
    • The Journal of Fisheries Business Administration
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    • v.31 no.1
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    • pp.1-12
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    • 2000
  • The experience of many countries strongly suggests that bad governments and institutions have been a serious, if not the most serious, obstacle to economic growth and industry-structural adjustments. All public sectors pursue a mix of both predatory and productive activities-bad governments emphasizing the former, while good governments finding a way of promoting the later. In fishery public policy studies, much confusion exists about the roles of policy illustration and prescription. In general fishery public sectors involve collective actions by numerous individuals under conditions of uncertainty, complexity, bounded rationality, and imperfect information structure. All collective fisheries action organizations consist of a center(e.g., government), which leads fishery group actions, and peripheral participants(e.g., fishermen), which are controlled by the government. A paradigm is developed that gives both theoretical and empirical meaning to the constitutional determination of fisheries political preference function or fishery public sector governance structures. Three relevant spaces are specified: policy instrument, results, and constitutional. The collective-choice rules of the constitutional space structure the tradeoff between public and special fishery interest groups. Fishery public sectors seeking sustainable reductions in wasteful rent-seeking fishing activities should select constitutional principles and institutional structures that tend to promote resource sustainability. In particular, the effects of internal and external events on fisheries may result in a greater or lesser concentration of interest group power. Thus, the structure of the fishereis political power must be assessed in any prescriptive evaluation of alternative fishery governance weights.

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Verification of The Variable-Speed Wind Turbine Control System by Using the Simulator (시뮬레이터를 이용한 가변속 풍력발전기 제어시스템 검증)

  • Cha, Sam-Gon;Han, Sang-Yul;Cha, Jong-Hwan;Choi, Won-Ho;Lee, Seung-Kuh
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.06a
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    • pp.370-373
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    • 2007
  • For the development of wind turbine, generally simulator is used. Simulator include wind turbine components. e.g blades, pitch and pitching method, rotor, yaw system, tower, drive train and so on. Few the more, it include a external circumstance. e.g wind speed, wind direction, air density. these basic parameters be used for the control of wind turbine by wind turbine controller in wind turbine simulator. The wind turbine controller can be designed in the wind turbine simulator. But a developer must make the real control system that will be made using PLC or PC or other processor. The developer must verify the function of control system. that is control algorithm , I/O function, communication, sequence and so on. This verification is possible if we substitute the real wind turbine control system for wind turbine controller in the simulator.

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Grouping the Ginseng Field Soil Based on the Development of Root Rot of Ginseng Seedlings (유묘 뿌리썩음병 진전에 따른 이산재배 토양의 유별)

  • 박규진;박은우;정후섭
    • Korean Journal Plant Pathology
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    • v.13 no.1
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    • pp.37-45
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    • 1997
  • Disease incidence (DI), pre-emergence damping-off (PDO), days until the first symptom appeared (DUS), disease progress curve (DPC), and area under disease progress curve (AUDPC) were investigated in vivo after sowing ginseng seeds in each of 37 ginseng-cultivated soils which were sampled from 4 regions in Korea. Non linear fitting parameters, A, B, K and M, were estimated from the Richards' function, one of the disease progress models, by using the DI at each day from the bioassay. Inter- and intra-relationships between disease variables and stand-missing rate (SMR) in fields were investigated by using the simple correlation analysis. Disease variables of the root rot were divided into two groups: variables related to disease incidence, e.g., DI, AUDPC and A parameter, and variables related to disease progress, e.g., B, K and M parameters. DI, AUDPC, and DUS had significant correlations with SMR in ginseng fields, and then it showed that the disease development in vivo corresponded with that in fields. Soil samples could be separated into 3 and 4 groups, respectively, on the basis of the principal component 1 (PC1) and the principal component 2 (PC2), which were derived from the principal component analysis (PCA) of Richards' parameters, A, B, K and M. PC1 accounted for B, K and M parameters, and PC2 accounted for A parameter.

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Assortment Optimization under Consumer Choice Behavior in Online Retailing

  • Lee, Joonkyum;Kim, Bumsoo
    • Management Science and Financial Engineering
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    • v.20 no.2
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    • pp.27-31
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    • 2014
  • This paper studies the assortment optimization problem in online retailing by using a multinomial logit model in order to take consumer choice behavior into account. We focus on two unique features of online purchase behavior: first, there exists increased amount of uncertainty (e.g., size and color of merchandize) in online shopping as customers cannot experience merchandize directly. This uncertainty is captured by the scale parameter of a Gumbel distribution; second, online shopping entails unique shopping-related disutility (e.g., waiting time for delivery and security concerns) compared to offline shopping. This disutility is controlled by the changes in the observed part of utility function in our model. The impact of changes in uncertainty and disutility on the expected profit does not exhibit obvious structure: the expected profit may increase or decrease depending on the assortment. However, by analyzing the structure of the optimal assortment based on convexity property of the profit function, we show that the cardinality of the optimal assortment decreases and the maximum expected profit increases as uncertainty or disutility decreases. Therefore, our study suggests that it is important for managers of online retailing to reduce uncertainty and disutility involved in online purchase process.

On the Volumetric Balanced Variation of Ship Forms (체적 밸런스 선형변환방법에 대한 연구)

  • Kim, Hyun-Cheol
    • Journal of Ocean Engineering and Technology
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    • v.27 no.2
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    • pp.1-7
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    • 2013
  • This paper aims at contributing to the field of ship design by introducing new systematic variation methods for ship hull forms. Hull form design is generally carried out in two stages. The first is the global variation considering the sectional area curve. Because the geometric properties of a sectional area curve have a decisive effect on the global hydrodynamic properties of ships, the design of a sectional area curve that satisfies various global design conditions, e.g., the displacement, longitudinal center of buoyancy, etc., is important in the initial hull form design stage. The second stage involves the local design of section forms. Section forms affect the local hydrodynamic properties, e.g., the local pressure in the fore- and aftbody. This paper deals with a new method for the systematic variation of sectional area curves. The longitudinal volume distribution of a ship depends on the sectional area curve, which can geometrically be controlled using parametric variation and a variation that uses the modification function. Based on these methods, we suggest a more generalized method in connection with the derivation of the lines for a new design compared to those for similar ships. This is the so-called the volumetric balanced variation (VOB) method for ship forms using a B-spline modification function and an optimization technique. In this paper the global geometric properties of hull forms are totally controlled by the form parameters. We describe the new method and some application examples in detail.

Effective Factors on Association between Liver/kidney Function and Blood-Cd Level in the Korean Urban People (도시거주자의 혈중 카드뮴 농도와 간 및 신장 기능과의 상관성 평가)

  • 김호현;임영욱;임종한;양지연;신동천
    • Environmental Analysis Health and Toxicology
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    • v.18 no.1
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    • pp.33-44
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    • 2003
  • The possibility that liver and kidney function is adversely affected by current levels of environmental exposure to cadmium (Cd) as investigated in adult men and women in the general population in Seoul. From February to August in 2001, blood and morning spot urine samples were collected from 136 not occupationally exposed group (age range 20∼75 years) at 4 survey sites throughout seoul. Liver and kidney function parameters in serum and urine were examined by conventional methods. The questionnaire included factors, i.e. sex, age, smoking, alcohol, diet habit etc. The geometric mean values for Cd in blood (Cd-B) were 1.43 $\mu\textrm{g}$/1, It seemed prudent to conclude that liver and kidney function as not disturbed by the current environmental exposure to Cd in study.

A Short-term Forecasting of Water Supply Demands by the Transfer Function Model (Transfer Function 모형을 이용한 수도물 수요의 단기예측)

  • Lee, Jae-Joon
    • Journal of Korean Society of Water and Wastewater
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    • v.10 no.2
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    • pp.88-103
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    • 1996
  • The objective of this study is to develop stochastic and deterministic models which could be used to synthesize water application time series. Adaptive models using mulitivariate ARIMA(Transfer Function Model) are developed for daily urban water use forecasting. The model considers several variables on which water demands is dependent. The dynamic response of water demands to several factors(e.g. weekday, average temperature, minimum temperature, maximum temperature, humidity, cloudiness, rainfall) are characterized in the model by transfer functions. Daily water use data of Kumi city in 1992 are employed for model parameter estimation. Meteorological data of Seonsan station are utilized to input variables because Kumi has no records about the meteorological factor data.To determine the main factors influencing water use, autocorrelogram and cross correlogram analysis are performed. Through the identification, parameter estimation, and diagnostic checking of tentative model, final transfer function models by each month are established. The simulation output by transfer function models are compared to a historical data and shows the good agreement.

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A FAMILY OF HOLOMORPHIC FUNCTIONS ASSOCIATED WITH MUTUALLY ADJOINT FUNCTIONS

  • K.R. KARTHIKEYAN;G. MURUGUSUNDARAMOORTHY;N.E. CHO
    • Journal of applied mathematics & informatics
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    • v.42 no.4
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    • pp.997-1006
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    • 2024
  • In this paper, making use of symmetric differential operator, we introduce a new class of ℓ-symmetric - mutually adjoint functions. To make this study more comprehensive and versatile, we have used a differential operator involving three-parameter extension of the well-known Mittag-Leffler functions. Mainly we investigated the inclusion relation and subordination conditions which are the main results of the paper. To establish connections or relations with earlier studies, we have presented applications of main results as corollaries.

Kinetic Studios of Milk Gelification (Part 1) (우유의 Gel화에 관한 동력학적 연구 (제1보))

  • LEE Keun-Tai
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.19 no.3
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    • pp.177-182
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    • 1986
  • The dynamic mechanical properties of milk gel were examined as function of temperature, concentrations of milk and enzyme. The real and imaginary parts of the complex rigdity G' and G' were measured at $2\%$ strain and 5 rad/s of frequency. The results showed that the rigidity of milk gel was dependent on the concentration of milk (C) in such a way that $\sqrt{G'}{\propto}C$. It was found that gel point ($t_g$) was dependent on the concentration of milk as $t_g{\propto}C$, and on the concentration of enzyme as $t_g{\propto}\;1/(E)$, The activation energy of enzymatic reaction stage and coagulation stage were $21.1{\pm}5.8\;kcal/mol$ and $26.4{\pm}1.14\;kcal/mol$, respectively.

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Influence of Intracerebroventricular Ketanserin on Rabbit Renal Function (가토신장기능에 미치는 뇌실내 Ketanserin의 영향)

  • Kook, Young-Johng;Kim, Kyung-Keun;Lim, Young-Chai;Kim, Yoo-Nam;Kook, Hoon
    • The Korean Journal of Pharmacology
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    • v.26 no.2
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    • pp.153-160
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    • 1990
  • 5-Hydroxytryptamine (5-HT) was reported to elicit natriuresis and diuresis when given intracerebroventricularly (icv) and these effects were shown to be abolished by icv methysergide, $5-HT{_1}$ antagonist, thus suggesting that central tryptaminergic system may also participate in the regulation of renal function. We tried in this study to elucidate the role of $5-HT_2$ receptors in the central tryptaminergic regulation of renal function, observing the effects of icv ketanserin, a specific $5-HT_2$ antagonist. Ketanserin (KET) icv in doses of $120{\mu}g$ $(=0.3\;{\mu}moles)/kg$ produced significant natriuresis without affecting renal hemodynamics, indicating that it resulted from decreased tubular Na reabsorption. Systemic blood pressure decreased slightly but significantly. When given iv, no significant effect was observed. 5-HT, $200{\mu}g/kg$ icv, produced mild but significant natriuresis and diuresis. However, after KET, $40{\mu}\;g/kg$ icv, a dose which minimally affects renal function, the natriuresis and diuresis by 5-HT was greatly augmented, with the fractional excretion of filtered sodium reaching 9.3%. The renal effects of other biogenic amines administered icv, such as norepinephrine, dopamine and histamine, were not significantly affected by the KET pretreatment. These observations suggest that central tryptaminergic system influences renal function in dual ways, i.e., natriuretic and diuretic influence via $5-HT_1$ receptors, whereas $5-HT_2$ subtypes mediate the antinatriuretic and antidiuretic effects, and that the central tryptaminergic system plays a role in the regulation of rabbit renal function.

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