• 제목/요약/키워드: Production Volume Function

검색결과 80건 처리시간 0.026초

식물플랑크톤 일차생산력의 새로운 시간 적분 알고리즘 (Time Integration Algorithm for the Estimation of Daily Primary Production)

  • 박종규;김응권
    • 한국해양학회지:바다
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    • 제15권3호
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    • pp.124-132
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    • 2010
  • 해양 식물플랑크톤 일차생산력의 전 지구적 중요성에도 불구하고 자료 처리상의 어려움 때문에 국내에서는 신뢰할만한 자료가 많지 않다. 식물플랑크톤 일차생산력은 시간-수심 적분 과정을 거쳐 최종적으로 단위 면적당 하루 일차생산력을 구하지만, 시간 적분에 대한 연구결과는 많지 않은 편이다. 본 연구에서는 단위 시간당 일차생산력을 시간 적분하여 하루 일차생산력을 계산하는 수학적 모델을 제시하고 새만금호를 대상으로 모델의 실효성을 검정해 보았다. 검정 결과, 시간 적분 모델이 일사량 실측치를 대입하여 합산한 결과와 잘 일치하였다. 일차생산력 계산을 위한 기초 광량 자료는 변화가 심한 일 자료보다 한 달 또는 한 주간 평균 자료를 대입하는 것이 더 신뢰성 있는 결과에 도움이 되는 것으로 판단되었다. 일차생산력 수직적분은 수직적으로 불균일한 식물플랑크톤 분포 때문에 어려움이 있으나, 엽록소 분포를 몇 가지 유형으로 분류하여 수식화한 다음, 각 수식을 시간 적분한 일차생산력 모델과 합성하여 적분하면 해결할 수 있을 것으로 판단된다.

Comparative Investigation of the Hydrogen Production of Zinc/carbons Prepared from Non-activated Carbon and Surface-modified Activated Carbon by Treatment with Zinc Salts

  • Oh, Won-Chun
    • 한국세라믹학회지
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    • 제44권11호
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    • pp.607-612
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    • 2007
  • Zn-AC and Zn-H-AC series prepared from non- and surface-modified activated carbon were investigated in terms of their hydrogen production capacity. An increase in the concentration of the zinc salts used with these series was shown to lead to a decrease in the values of the surface textural properties. The existence of zinc complexes on the surface was confirmed from an analysis of XRD data. The SEM micrographs of the two different sample types showed that the transformation of the carbon surface with an acid pre-treatment significantly change the metal contents on the surfaces of the carbon matrix. The EDX spectra indicated that all of the samples were richer in the amount of oxygen and zinc compared to any other elements. The results obtained using the Boehm's titration method showed that the positive introduction of the acidic groups on the carbon surfaces with the acid treatment is correlated with an increase in the amounts of zinc complexes with variation of the acidic groups. In terms of the hydrogen production performance, the volume fractions of the Zn-H-AC series were found to produce higher amounts than the Zn-AC series as a function of the metal contents considering the effects of the acid treatment.

Hygrothermal sound radiation analysis of layered composite plate using HFEM-IBEM micromechanical model and experimental validation

  • Binita Dash;Trupti R Mahapatra;Punyapriya Mishra;Debadutta Mishra
    • Structural Engineering and Mechanics
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    • 제89권3호
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    • pp.265-281
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    • 2024
  • The sound radiation responses of multi-layer composite plates subjected to harmonic mechanical excitation in hygrothermal environment is numerically investigated. A homogenized micromechanical finite element (FE) based on the higher-order mid-plane kinematics replicating quadratic function as well as the through the thickness stretching effect together with the indirect boundary element (IBE) scheme has been first time employed. The isoparametric Lagrangian element (ten degrees of freedom per node) is used for discretization to attain the hygro-thermo-elastic natural frequencies and the modes of the plate via Hamilton's principle. The effective material properties under combined hygrothermal loading are considered via a micromechanical model. An IBE method is then implemented to attain structure-surrounding coupling and the Helmholtz wave equation is solved to compute the sound radiation responses. The effectiveness of the model is tested by converging it with the similar analytical/numerical results as well as the experimentally acquired data. The present scheme is further hold out for solving diverse numerical illustrations. The results revealed the relevance of the current higher-order FE-IBE micromechanical model in realistic estimation of hygro-thermo-acoustic responses. The geometrical parameters, volume fraction of fiber, layup, and support conditions alongside the hygrothermal load is found to have significant influence on the vibroacoustic characteristics.

A Reliability Verification of Screening Time Prediction Reporting of 'Cine-Hangeul'

  • Jeon, Byoung-Won
    • Journal of Multimedia Information System
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    • 제7권2호
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    • pp.141-146
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    • 2020
  • Cine-Hangeul is a program that can predict the running time of a movie based on the screenplay before production. This paper seeks to verify the prediction reporting function of Cine-Hangeul, which is the standard Korean screenplay format. Moreover, this paper presents a method to increase the accuracy of the Cine-Hangeul reporting function. The objective of this paper is to offer a correction method based on scientific evidence because the current Cine-Hangeul reporting function has many errors. The verification process for five scenarios and movies confirmed that the default setting value of Cine- Hangeul's screening time prediction reporting was many errors. Cine-Hangeul analyzes the amount of textual information to predict the time of the scene and the time of the dialogue and helps predict the total time of the movie. Therefore, if a certain amount of text information is not available, the accuracy is unreliable. The current Cine-Hangeul prediction report confirms that the efficiency is high when the scenario volume is about 90 to 100 pages. As a result, prediction of screening time by Cine-Hangeul, a Korean scenario standard format program, confirmed the verification that it could secure the same level of reliability as the actual screening time by correcting the reporting settings. This verification also affirms that when applying about 50 percent of the basic set of screening time reporting, it is almost identical to the screening time.

탄소저장(炭素貯藏) 및 목재생산효과(木材生産效果) 중심(中心)의 산림경영계획(山林經營計劃)을 위한 다목적(多目的) 선형계획법(線型計劃法)의 응용(應用) (Optimal Forest Management Planning for Carbon Sequestration and Timber Production Using Multiobjective Linear Programming)

  • 박은식;정주상
    • 한국산림과학회지
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    • 제89권3호
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    • pp.335-341
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    • 2000
  • 이 연구에서는 탄소저장 및 목재생산효과를 동시에 고려하여 최적 산림경영계획을 수립하기 위한 다목적 선형계획수식모형을 개발하고, 사례연구를 통해 탄소저장과 목재생산효과의 선호도에 따른 최적 산림수확계획의 변화 경향을 분석하였다. 연구대상지로는 홍천의 가리산 지역을 선정하였으며, 선형계획수식모형에는 비감소수확, 수확벌채량 및 수확면적의 최대, 최소범위, 계획기간말의 임상구조 등을 제약하는 다수의 조건들을 포함시켰다. 또한 탄소저장 및 목재생산효과와 같이 상충적인 요소를 경영계획에 반영하기 위한 합리적 절충방안의 하나로 경영목적의 선호도에 따른 결합생산가능곡선을 제시하였다.

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A Design Method of Gear Trains Using a Genetic Algorithm

  • Chong, Tae-Hyong;Lee, Joung sang
    • International Journal of Precision Engineering and Manufacturing
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    • 제1권1호
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    • pp.62-70
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    • 2000
  • The design of gear train is a kind of mixed problems which have to determine various types of design variables; i,e., continuous, discrete, and integer variables. Therefore, the most common practice of optimum design using the derivative of objective function has difficulty in solving those kinds of problems and the optimum solution also depends on initial guess because there are many sophisticated constrains. In this study, the Genetic Algorithm is introduced for the optimum design of gear trains to solve such problems and we propose a genetic algorithm based gear design system. This system is applied for the geometrical volume(size) minimization problem of the two-stage gear train and the simple planetary gear train to show that genetic algorithm is better than the conventional algorithm solving the problems that have continuous, discrete, and integer variables. In this system, each design factor such as strength, durability, interference, contact ratio, etc. is considered on the basis of AGMA standards to satisfy the required design specification and the performance with minimizing the geometrical volume(size) of gear trains

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공적분·벡터오차수정모형을 활용한 벙커유 가격의 장기균형 수렴에 관한 실증분석 (An Empirical Analysis on the Long-term Balance of Bunker Oil Prices Using the Co-integration Model and Vector Error Correction Model)

  • 안영균;이민규
    • 무역학회지
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    • 제44권1호
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    • pp.75-86
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    • 2019
  • This study performs a factor analysis that affects the bunker oil price using the Co-integration model and Vector Error Correction Model (VECM). For this purpose, we use data from Clarkson and the analysis results show 17.6% decrease in bunker oil price when the amount of crude oil production increases at 1.0%, 10.3% increase in bunker oil price when the seaborne trade volume increases at 1.0%, 1.0% decrease in bunker oil price when total volume of vessels increases at 1.0%, and 0.003% increase in bunker oil price when 1.0% increase in world GDP, respectively. This study is meaningful in that this study estimates the speed of convergence to long-term equilibrium and identifies the price adjust mechanism which naturally exists in bunker oil market. And it is expected that the future study can provide statistically more meaningful econometric results if it can obtain data during more long-periods and use more various kinds of explanatory variables.

Effects of aflatoxin B1 combined with ochratoxin A and/or zearalenone on metabolism, immune function, and antioxidant status in lactating dairy goats

  • Huang, Shuai;Zheng, Nan;Fan, Caiyun;Cheng, Ming;Wang, Shang;Jabar, Adil;Wang, Jiaqi;Cheng, Jianbo
    • Asian-Australasian Journal of Animal Sciences
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    • 제31권4호
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    • pp.505-513
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    • 2018
  • Objective: This experiment investigated the effects of aflatoxin B1 (AFB1) alone or mixed with ochratoxin A (OTA) and/or zearalenone (ZEA) on the metabolism, immune function, and antioxidant status of dairy goats. Methods: Fifty lactating Laoshan dairy goats were randomly assigned to one of five treatment groups (n = 10) for 14 days. Goats were fed no additive (control) or administered with $50{\mu}g\;AFB1/kg$ dry matter (DM) (AFB1), $50{\mu}g\;AFB1/kg$ $DM+100{\mu}g\;OTA/kg$ DM (AFB1+OTA), $50{\mu}g\;AFB1/kg$ $DM+500{\mu}g\;ZEA/kg$ DM (AFB1+ZEA), or $50{\mu}g\;AFB1/kg$ $DM+100{\mu}g\;OTA/kg$ $DM+500{\mu}g\;ZEA/kg$ DM (AFB1+OTA+ZEA). Results: Dry matter intake and milk production were lower in goats fed AFB1+OTA+ZEA than in controls. Supplementation with AFB1, OTA, and ZEA significantly decreased red blood cell count, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, and mean platelet volume, and significantly increased white blood cell count, when compared with the control group. Compared with control, the combination of AFB1, OTA, and ZEA significantly increased alanine aminotransferase (ALT) and alkaline phosphatase (ALP) activities, total bilirubin (TBIL), interleukin-6, and malondialdehyde (MDA), but significantly reduced immunoglobulin A concentration, the activities of superoxide dismutase (SOD) and glutathione peroxides (GSH-Px), and total antioxidant capacity (T-AOC) in serum. Administration of AFB1 combined with OTA led to higher ALP, ALT, TBIL, and MDA, as well as lower milk production, SOD and GSH-Px activities, and T-AOC, than administration of AFB1 combined with ZEA. Conclusion: The mixture of AFB1, OTA, and ZEA exerted the greatest adverse effects on dairy goats, meanwhile the deleterious damage of the other mycotoxin combinations were in varying degrees. The findings of this study could provide guidance for the prevention and treatment of the consequences of contamination of animal feeds with combinations of mycotoxin.

Letrozole, an aromatase inhibitor, improves seminal parameters and hormonal profile in aged endangered Markhoz bucks

  • Rezaei, Ako;Vaziry, Asaad;Farshad, Abbas
    • Animal Bioscience
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    • 제35권11호
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    • pp.1666-1674
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    • 2022
  • Objective: Letrozole, a potent aromatase inhibitor, is known to have the potential to modify male reproductive function by altering sex hormone levels. This study aimed to evaluate the semen and testicular characteristics and hormonal profile of aged Mrakhoz bucks (Capra hircus) treated with letrozole. Methods: Twelve Markhoz male goats, aged between 4.5 to 5.5 years with an average body weight (BW) of 61.05±4.97 kg were used for the study. Animals were randomly divided into two equal groups and subcutaneously received either 0.25 mg/kg BW of letrozole or a control every week for 2 months. The semen collections were performed every 10 days, and blood samples and testicular biometric records were collected at 20 days intervals. Results: Letrozole causes increased testosterone and follicle-stimulating hormone levels, testosterone to estradiol ratio, semen index and reaction time during the period from 20th to 60th days (p<0.05). Furthermore, letrozole-treated bucks had higher semen volume, sperm concentration, and total sperm per ejaculate from 30th to 60th days (p<0.05). However, no differences occurred between the groups in scrotal circumference, relative testicular volume, semen pH, abnormality, acrosome integrity, and membrane integrity of sperm during the study (p>0.05). The serum luteinizing hormone levels, sperm viability, motility, and progressive motility increased, and estradiol levels decreased after 40th to 60th days of letrozole treatment (p<0.05). Conclusion: Letrozole application to aged Markhoz bucks provokes reproductive hormonal axis which, in turn, induces enhancement of semen production and quality.

멀티 셀 유연생산환경을 위한 통합운용시스템 (An Integrated Shop Operation System for Multi-Cell Flexible Manufacturing Systems under Job Shop Environments)

  • 남성호;류광열;신정훈;권기억;이석우
    • 한국정밀공학회지
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    • 제29권4호
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    • pp.386-394
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    • 2012
  • Recent trends in the flexible manufacturing systems are morphing cell control for the shop-wide production operation system and providing the integrated operation and execution system together with vendor-specific FMC/FMS platform. In these requirements, the shop-floor level operation system plays a role of coordinating the control activity of each cell, and has to provide flexibility for the complexity of mixed operations of various cells. This paper suggests a system architecture for the mixed environments of multi-cells and job shop, its corresponding enabling technologies based on comparative studies with other related studies and commercialized systems. This approach includes a process definition model considering the integration with upper BOM-BOP and external service modules, and reconfigurable device-level interface which provides dynamic interconnections with machine tools and cell controllers. The function modules and their implementation results are also described to provide the feasibility of the proposed approaches as the flexible shop-floor operation system for the multi-cell environments.