• Title/Summary/Keyword: Maximum quantity

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Bioeconomic Management Policy for Fisheries Resources (생물경제학적 어업자원 관리정책에 관한 연구)

  • PYO, Hee-Dong;KWON, Suk-jae
    • Journal of Fisheries and Marine Sciences Education
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    • v.16 no.1
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    • pp.84-98
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    • 2004
  • Due to a publicly owned resources, the overexploitation of the fisheries resources can result in externalities in the form of reduced future levels of yield. These problems can be theoretically improved through effective management of the fishery. The paper illustrates maximum sustainable yield(MSY), maximum economic yield(MEY) and F0.1 level of fishing mortality as the concept of optimal yield, and it theoretically shows that MSY is more appropriate for the optimal yield than MEY where prices increase even though MEY achieves the maximization of economic rent in a fishery assuming constant prices. And the paper presents several fisheries management tools and policies such as input controls, output controls and taxes. As the traditional approach to fishery management, input controls involve restrictions on the physical inputs into the production process(e.g. capital, time or technology) and output controls involve limits on the quantity of fish that can be landed. To introduce user cost into the harvest decisions of rent-seeking fishers, taxation, as a bioeconomic management policy of the fisheries, directly addresses the problems associated with the resource being unpriced. As most fisheries management plans, however, have increasing fisher income as an objective, taxes have not been introduced into any fisheries management policies despite their theoretical attraction.

Effect of Nitrogen Sources on the Production of Polyols by Aureobasidium pullulans

  • Yun, Jong-Won;Kang, Sun-Chul;Song, Seung-Koo
    • Journal of Microbiology and Biotechnology
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    • v.6 no.1
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    • pp.60-62
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    • 1996
  • Aureobasidium pullulans produced three kinds of extracellular polyols e.g. glycerol, mannitol, and sorbitol from either sucrose, glucose, fructose or mannose. Sorbitol was selectively produced when urea was used as a sole nitrogen source, and the amounts of sorbitol produced rapidly reached a plateau after 50 h where its maximum quantity was about 20 g/l with sucrose.

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Parameter Estimation in a Complex Non-Stationary and Nonlinear Diffusion Process

  • So, Beong-Soo
    • Journal of the Korean Statistical Society
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    • v.29 no.4
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    • pp.489-499
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    • 2000
  • We propose a new instrumental variable estimator of the complex parameter of a class of univariate complex-valued diffusion processes defined by the possibly non-stationary and/or nonlinear stochastic differential equations. On the basis of the exact finite sample distribution of the pivotal quantity, we construct the exact confidence intervals and the exact tests for the parameter. Monte-Carlo simulation suggests that the new estimator seems to provide a viable alternative to the maximum likelihood estimator (MLE) for nonlinear and/or non-stationary processes.

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A Study on Reliability Evaluation of Application Software using Binomial-Type Model (이항형 모형을 이용한 응용 소프트웨어 의 신뢰성 평가에 관한 연구)

  • 조성건;이상철
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.15 no.25
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    • pp.53-62
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    • 1992
  • Computer software users develop and utilize their application software by themselves since Processing methods are different by quantity and qualify of the information The developed model needs input data and error numbers generated during the testing phases. However. total error numbers of the existing model and each error time was needed as data for developing the new model. But, maximum likelihood estimation must be used to exponential model of binomial-type and estimating of parameters by using the searched data. Parameter estimation can be done with trial and error or simulation.

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Seasonal Fluctuation of Phytoplankton in Inchon Dock-Autumn, 1976 (인천항 선거내 식물성 플랑크톤의 추계동태에 대하여)

  • 정영호
    • Journal of Plant Biology
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    • v.20 no.3
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    • pp.135-140
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    • 1977
  • A series of observations of phytoplankton were made at seven station with two control stations in Inchon Dock to clarify the quantity, quality and standing crop of phytoplankton from Oct. to Nov., 1976. Thirty seven species of phytoplankton, representing 18 genera, 36 species, 1 forma were taken in this research. Chaetoceros decipiens, Rhizosolenia delicatula, Hemiaulus sinensis, Chaetoceros affinis and Skeletonema costatum were the dominant species in this area during two moths. By the ecological division, the neritic species occupied 86.5% of total phytoplankton composition. Standing crop of phytoplankton represented much variation: ranging from 263 to 1, 614, 832 cells/l. The maximum happened at station 1 on November.

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(${\lceil}$Effects of Ni addition on the Structure and Strength of gray cast iron containing aluminium${\rfloor}$ (("저(低)알루미늄 합금주철(合金鑄鐵)의 응고조직(凝固組織)과 기계적(機械的) 성질(性質)에 미치는 니켈의 영향(影響)")

  • Kang, Nak-Won;Kang, In-Chan
    • Journal of Korea Foundry Society
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    • v.7 no.4
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    • pp.352-357
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    • 1987
  • Recently there were many studies on the development of cast iron for increasing strength, thermal resistance and mechanical properties, etc. The effects on mechanical properties and variation of solidification structure of hypo-eutectic cast iron was investigated when Ni(Al) was added with a fixed quantity of Al(Ni) content. The conclusions are as follows. 1) Tensile strength was the maximum(over 41 kg/ $mm^2$) when Al is added about 0.72%. 2) Torsional strength and angle were increased with increasing Al content and represents maximum value, when Al and Ni content are 1.5 and 2.0%. 3) With increasing Ni content, tensile strength decreased because of the effect of graphite coarsening. But torsional strengths were increased with the appropriate addition of (Ni%+Al%) content because of the effect of strengthened matrix.

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Tracking Control of Maximum Power Point of Photovoltaic Array by using the Microprocessor (Microprocessor를 이용한 태양전지의 최대 출력점 추적 제어)

  • Han, K.H.;Jang, K.H.;Kwon, H.;Kim, D.K.;Lee, W.K.;Kang, S.W.
    • Proceedings of the KIEE Conference
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    • 1991.07a
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    • pp.492-495
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    • 1991
  • This paper proposes the microprocessor-based step-up chopper system used for the battery charge from the photovoltaic arrays. The proposed scheme tracks the maximum power point by analyzing the voltage and power phasors which vary as the solar irradiation quantity. In this system, protection for the overcharge and overdischarge in also provided.

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Storage of Waste-Brown Seaweed and Degradation of Alginate Using Microorganism (미생물을 이용한 미역폐기물의 저장 및 알긴산염 저분자화)

  • An, Sang Jun;Kim, Yeong Suk;Park, Gwon Pil
    • Journal of Environmental Science International
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    • v.13 no.3
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    • pp.313-318
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    • 2004
  • We studied a storage of waste-brown seaweed at room temperature and degradation of alginate in seaweed by microorganism DS-02. The seaweeds, mixed with 5.0 wt% DS-02 and sealed in vinyl package without any other treatment, could be stored longer than 1 year without spoilage at room temperature. During the storage process, the alginate of seaweed was decomposed by enzyme of DS-02 and the molecular weight of alginate decreased to about 1/10 of initial quantity. DS-02 growed as fast as it had maximum weight after 24 hour culture and it's enzyme had a maximum activity of alginate degradation at $40^{\circ}C.$ The seaweed sample became particles in DS-02 culture solution and the M. W of alginate decreased to about 1/10 of initial value after 24 hour decomposition. The effect of alginate degradation with DS-02 was similar to that of degradation with 3.0 M HCI solution for 24 hour.

Symbiotic Nitrogen Fixation Activity and Environmental Factors of Robinia Pseudo-acacia L. (아까시나무 ( Robinia pseudo - acacia L. ) 의 공생적 질소고정 활성과 환경요인)

  • Hong, Sung-Jin;Song, Seung-Del
    • The Korean Journal of Ecology
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    • v.13 no.2
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    • pp.93-100
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    • 1990
  • The activity of symbiotic -fixation and environmental factors of Robinia pseudo-acacia L., bearing root nodules, were quantitatively analyzed during the growing period. Among changes of total nitrogen and phosphorus contents of each organ, leaves showed prominent decreases from the highest quantity of the early growing period to the lowest of the late period. The rhizosphere showed acidic pH and low level of nitrogen, phosphorus and organic matter contents during the growing period. -fixation activity of nodules initiated from April and showed the maximum value of 190 $\mu$/g DW/hr in late June and than decreased to 50$\mu$M/g DW/hr during the rainy and dry season. Another peak of the activity attained 246$\mu$M/g DW/hr in the late growing stage of September. The maximum value of nitrogen fixation activity was observed at the conditions of pH7, $25\{\circ}C$ of temperature and 20 Kpa of oxygen partial pressure.

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A Study on the Applicability of Shrinkage Reduction Effect of Light-weight Aggregate Concrete (경량골재 콘크리트의 수축 저감효과에 관한 적용성 연구)

  • Lim, Sang-Jun;Bang, Chang-Joon;Park, Jong-Hyok
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.11a
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    • pp.175-176
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    • 2011
  • Applying previous studies performed in the moisture transportation characteristics and shrinkage of lightweight concrete application of shrinkage reduction is to discuss. Applicability of shrinkage reduction effect of lightweight concrete applies for the analysis of PSC girder bridge beam placed on the construction site. Stress of the concrete bridge deck, rebar quantity is calculated by effective elastic modulus method and crack risk is assessed by moisture transport and differential shrinkage analysis. After approximately 10 days maximum tensile stress occurs 6MPa, similar to the case of normal concrete, a maximum tensile stress occurs 3MPa in lightweight concrete and comparing to normal concrete stress was reduced to approximately 50%. Normal and lightweight concrete crack index, respectively, is reduced 1.6 to 1.2, 1.2 to 0.9 in surface and boundary region. Therefore, reduction in shrinkage of concrete were able to confirm reduction of crack risk.

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