• Title/Summary/Keyword: simultaneous equations

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순환식 병류형 유채씨 건조 시뮬레이션 (Circulating Concurrent-flow Drying Simulation of Rapeseed)

  • 한재웅;금동혁;김웅;레안득;조성호;김훈
    • Journal of Biosystems Engineering
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    • 제35권6호
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    • pp.401-407
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    • 2010
  • In this study, computer simulations were conducted to assess the use of a circulating concurrent-flow dryer for rapeseed drying and to determined the effect of this drying method on the germination ratio of rapeseed after the drying process was complete. The simultaneous heat and mass transfer between air and rapeseed in a concurrent-flow dryer was examined by simulation. The drying simulation was based on several parameters with sequent time series. Equations concerning air psychrometrics, physical properties, thermal properties, equilibrium moisture content, thin layer drying of rapeseed, etc. were all combined to solve the simulation models. Based on energy and mass transfer in the concurrent-flow drying model, a simulation program for the circulating concurrent-flow rapeseed dryer was built along with a detailed description of the mathematical solution to the model. A pilot scale circulating concurrent-flow dryer(200 kg/batch) was used to verify the fitness of the simulation program. A comparison between the experimental data and the model predicted results was presented and discussed. The drying parameters and germination ratio were analyzed and the accuracy of the simulation program was evaluated. The simulation program proved to be reliable and was shown to be a convenient tool for predicting rapeseed drying and germination ratio of rapeseed in a concurrent-flow dryer.

LC-MS/MS를 이용한 계지복령환(桂枝茯苓丸)의 동시분석 및 항산화 효능 연구 (Quantitative Analysis and Antioxidant Effects of Gyejibokryeong-hwan)

  • 서창섭;김온순;신현규
    • 생약학회지
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    • 제45권3호
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    • pp.240-248
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    • 2014
  • Gyejibokryeong-hwan (GJBRH) has been used for treatment of patients with climacteric syndrome. In this study, an ultra-performance liquid chromatography-electrospray ionization-mass spectrometer (UPLC-ESI-MS) method was established for the simultaneous quantification of seven marker compounds in GJBRH extract. In addition, we assessed the antioxidant effects of GJBRH. All analytes were separated by gradient elution using two mobile phases on a UPLC BEH $C_{18}$ column and maintained at $45^{\circ}C$. The antioxidant activities of GJBRH were evaluated by measuring free radical scavenging activities on 2,2'-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) and 1-1-diphenyl-2-picrylhydrazyl (DPPH). The inhibitory effects on low-density lipoprotein (LDL) oxidation were evaluated by the formation of thiobarbituric acid relative substances (TBARS) and relative electrophoretic mobility (REM). Regression equations of the seven compounds were acquired with $r^2$ values ${\geq}0.9988$. The amounts of the seven compounds, amygdalin, albiflorin, paeoniflorin, coumarin, cinnamic acid, cinnamaldehyde, and paeonol in GJBRH water extract were 21.71, 2.16, 17.17, 1.97, 0.40, 0.78, and 3.42 mg/g, respectively. The GJBRH showed the radical scavenging activity in a dose-dependent manner. The concentration required for 50% reduction ($RC_{50}$) against ABTS and DPPH radicals were $54.18{\mu}g/mL$ and $79.53{\mu}g/mL$. Furthermore, GJBRH reduced the oxidation properties of LDL induced by $CuSO_4$.

개방화가 한국의 경제성장과 환경오염에 미치는 영향 분석 (An Analysis on the Effects of Economic Growth and Environmental Pollution by Openness)

  • 조성택;조용성
    • 국제지역연구
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    • 제13권3호
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    • pp.269-286
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    • 2009
  • 환경과 개방화 그리고 경제성장에 대한 전통적 주장과 이를 반박하는 주장간의 논쟁은 끝나지 않고 있고, 두 가설을 검증할 수 있는 명확한 이론과 연구가 부재한 상황이다. 본 논문에서는 경제성장, 오염수준, 개방화를 설명하는 변수들을 설정하여 한국에서의 개방화와 경제성장, 오염수준과의 관계를 살펴보고 환경쿠즈네츠 곡선 가설을 검증하였다. 검증결과 한국에서는 개방화가 진전될수록 GDP가 상승하였고 개방화와 경제성장이 환경에 부정적 영향을 준다는 전통적 입장과 달리 환경수준과 개방화 및 경제성장은 정(正)의 관계로 나타났다. 즉, 개방화와 경제성장이 진행될수록 환경수준이 높아졌다. 이는 한국으로 유입되는 외국 자본의 성격이 오염집약적 산업이라기 보다는 친환경기술을 보유한 첨단기술산업임을 시사한다. 결론적으로 우리나라의 경우, 개방화와 외국자본의 유치는 환경오염을 가속화시킨다는 전통적인 가설과 달리 우리 경제를 성장시키고 환경수준을 높이는 효과를 가져온 것으로 추측된다. 아울러 교역이 증가해도 환경수준이 악화되지 않으며, 환경규제가 경제성장의 요인인 개방화를 감소시키지 않는다는 결론을 도출하였다. 이 결과는 수출경쟁력 약화 혹은 경제성장 둔화를 발생시키지 않고도 환경규제를 통해서 오염수준을 개선시킬 수 있음을 시사한다.

한국정부의 공공보건정책 투자사업이 경제성장에 미치는 영향 (An Empirical Study on the Effect of Public Health Investment on Economic Growth in Korea - focusing on the period of 2002 to 2006 -)

  • 임재영
    • 국제지역연구
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    • 제13권3호
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    • pp.239-267
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    • 2009
  • 공공보건정책사업에 대한 투자는 국민들의 건강수준을 향상시켜 미래의 의료비 절감효과가 나타날 것이며 질병부담 감소로 인한 생산성 손실이 감소할 것이며, 이러한 공공보건정책사업에 의한 건강증진효과는 경제성장을 촉발시키는 원동력이 될 것으로 사료된다. 본 논문에서는 공공보건정책사업의 투자효과를, 사업시행의 결과로 국민들의 질병으로 인한 사회경제적 비용이 감소했는지의 여부와 그 정도로 측정했으며, 특히 구축된 시계열 자료를 토대로 미시적 분석을 수행하기 위해, 질병으로 인한 사회경제적 비용규모가 가장 큰 5대 질환군 및 각 연령대별 인구집단을 대상으로 시행된 공공보건정책사업의 건강증진효과와 이들 효과가 경제성장에 미친 영향을 분석하였다. 분석결과를 요약하면, 질환별로는 호흡기계, 소화기계, 순환기계 및 감염성 질환 등에서 정책효과가 유의했고, 연령대별로는 0~9세, 10~19세, 40~49세, 50~59세, 60~69세 및 70세 이상 연령대에서 유의한 효과를 보였다. 아울러 이들 질병으로 인한 사회경제적 비용의 절감은 실질국내총생산의 증가에 통계적으로 유의하게 영향을 미쳤음을 알 수 있었다.

합성거동을 위한 유공판형 전단연결재의 강도평가에 관한 연구 (A Study on the Evaluation of Shear Resisting Capacity for the Various Perforated Shape Shear Connector)

  • 김영호
    • Composites Research
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    • 제21권5호
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    • pp.1-8
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    • 2008
  • 강합성교량에서 스터드 전단연결재 및 Perfobond 전단연결재와 관련된 문제를 해결하고, 콘크리트와 전단연결재가 동시에 파괴되도록 유도하기 위해 역 L형 유공판 전단연결재가 개발되었으며, FRP-콘크리트 합성바닥판에서는 FRP의 재료적 특성과 펄트루젼 생산방식을 고려하여 콘크리트와 FRP의 합성방안으로 Perfobond 형 FRP 전단연결재를 적용하고 있다. 이 연구는 기존 강재 Perfobond 전단연결재에 대한 문헌분석, 2면전단실험, 유한요소해석 등의 방법을 통해 역 L형 유공판 전단연결재, FRP 전단연결재에 대한 각각의 강도를 추정할 수 있는 강도평가식을 제안하였고, 제안한 평가식의 결과와 실험결과를 비교하여 타당성을 검증하였다.

Study on derivation from large-amplitude size dependent internal resonances of homogeneous and FG rod-types

  • Somaye Jamali Shakhlavi;Reza Nazemnezhad
    • Advances in nano research
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    • 제16권2호
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    • pp.111-125
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    • 2024
  • Recently, a lot of research has been done on the analysis of axial vibrations of homogeneous and FG nanotubes (nanorods) with various aspects of vibrations that have been fully mentioned in history. However, there is a lack of investigation of the dynamic internal resonances of FG nanotubes (nanorods) between them. This is one of the essential or substantial characteristics of nonlinear vibration systems that have many applications in various fields of engineering (making actuators, sensors, etc.) and medicine (improving the course of diseases such as cancers, etc.). For this reason, in this study, for the first time, the dynamic internal resonances of FG nanorods in the simultaneous presence of large-amplitude size dependent behaviour, inertial and shear effects are investigated for general state in detail. Such theoretical patterns permit as to carry out various numerical experiments, which is the key point in the expansion of advanced nano-devices in different sciences. This research presents an AFG novel nano resonator model based on the axial vibration of the elastic nanorod system in terms of derivation from large-amplitude size dependent internal modals interactions. The Hamilton's Principle is applied to achieve the basic equations in movement and boundary conditions, and a harmonic deferential quadrature method, and a multiple scale solution technique are employed to determine a semi-analytical solution. The interest of the current solution is seen in its specific procedure that useful for deriving general relationships of internal resonances of FG nanorods. The numerical results predicted by the presented formulation are compared with results already published in the literature to indicate the precision and efficiency of the used theory and method. The influences of gradient index, aspect ratio of FG nanorod, mode number, nonlinear effects, and nonlocal effects variations on the mechanical behavior of FG nanorods are examined and discussed in detail. Also, the inertial and shear traces on the formations of internal resonances of FG nanorods are studied, simultaneously. The obtained valid results of this research can be useful and practical as input data of experimental works and construction of devices related to axial vibrations of FG nanorods.

철근 콘크리트 전단벽에서 면외 하중이 면내 전단성능에 미치는 영향 (The Effect of Out-of-Plane Load on the In-Plane Shear Capacity of Reinforcement Concrete Shear Wall)

  • 신혜민;박준희
    • 한국지진공학회논문집
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    • 제28권2호
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    • pp.77-83
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    • 2024
  • The design shear strength equations of RC shear walls have been developed based on their performance under in-plane (IP) loads, thereby failing to account for the potential performance degradation of shear strength when subjected to simultaneous out-of-plane (OOP) loading. Most of the previous experimental studies on RC walls have been conducted in one direction under quasi-static conditions, and due to the difficulty in experimental planning, there is a lack of research on cyclic loading and results under multi-axial loading conditions. During an earthquake, shear walls may yield earlier than their design strength or fail unexpectedly when subjected to multi-directional forces, deviating from their intended failure mode. In this paper, nonlinear analysis in finite element models was performed based on the results of cyclic loading experiments on reinforced concrete shear walls of auxiliary buildings. To investigate the reduction trend in IP shear capacity concerning the OOP load ratio, parametric analysis was conducted using the shear wall FEM. The analysis results showed that as the magnitude of the OOP load increased, the IP strength decreased, with a more significant effect observed as the size of the opening increased. Thus, the necessity to incorporate this strength reduction as a factor for the OOP load effect in the wall design strength equation should be discussed by performing various parametric studies.

Quantitative analysis method for zingiber officinale water extract using high-performance liquid chromatography

  • Mohd S. Md Sarip;Nik M.A. Nik Daud;Mohd A. Mohd Zainudin;Lokman H. Ibrahim;Syahrul A. Saidi;Zuhaili Idham;Adilah Anuar
    • Advances in materials Research
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    • 제13권3호
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    • pp.233-241
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    • 2024
  • Quantitative analysis of the Zingiber Officinale sample using subcritical water extraction (SWE) was developed employing High-Performance Liquid Chromatography (HPLC) to bolster the advancement of this innovative green extraction process. This research focuses on three principal ginger bioactive compounds: 6-gingerol, 6-shagoal, and 10-gingerol. Various stages were undertaken to establish the quantitative analysis method, encompassing the optimisation of HPLC operating conditions and the formulation of standard calibration curves, yielding individual compound equations. A robust correlation within the calibration curve was achieved, exhibiting an r2 value of 0.9814 and an RSD of 5.00%. A simultaneous, swift, and dependable method was established with an injection time of 20 minutes and an 8-minute delay between injections, in contrast to the previous HPLC analysis requiring a 45-minute injection time for detecting and quantifying all components. Notably, no post-treatment was applied after the SWE process. This advancement allows for potential future online measurement of Zingiber Officinale bioactive compounds extracted using subcritical water extraction through this technology.

NIRS AS AN ESSENTIAL TOOL IN FOOD SAFETY PROGRAMS: FEED INGREDIENTS PREDICTION H COMMERCIAL COMPOUND FEEDING STUFFS

  • Varo, Ana-Garrido;MariaDoloresPerezMarin;Cabrera, Augusto-Gomez;JoseEmilioGuerrero Ginel;FelixdePaz;NatividadDelgado
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1153-1153
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    • 2001
  • Directive 79/373/EEC on the marketing of compound feeding stuffs, provided far a flexible declaration arrangement confined to the indication of the feed materials without stating their quantity and the possibility was retained to declare categories of feed materials instead of declaring the feed materials themselves. However, the BSE (Bovine Spongiform Encephalopathy) and the dioxin crisis have demonstrated the inadequacy of the current provisions and the need of detailed qualitative and quantitative information. On 10 January 2000 the Commission submitted to the Council a proposal for a Directive related to the marketing of compound feeding stuffs and the Council adopted a Common Position (EC N$^{\circ}$/2001) published at the Official Journal of the European Communities of 2. 2. 2001. According to the EC (EC N$^{\circ}$ 6/2001) the feeds material contained in compound feeding stufs intended for animals other than pets must be declared according to their percentage by weight, by descending order of weight and within the following brackets (I :< 30%; II :> 15 to 30%; III :> 5 to 15%; IV : 2% to 5%; V: < 2%). For practical reasons, it shall be allowed that the declarations of feed materials included in the compound feeding stuffs are provided on an ad hoc label or accompanying document. However, documents alone will not be sufficient to restore public confidence on the animal feed industry. The objective of the present work is to obtain calibration equations fur the instanteneous and simultaneous prediction of the chemical composition and the percentage of ingredients of unground compound feeding stuffs. A total of 287 samples of unground compound feeds marketed in Spain were scanned in a FOSS-NIR Systems 6500 monochromator using a rectangular cup with a quartz window (16 $\times$ 3.5 cm). Calibration equations were obtained for the prediction of moisture ($R^2$= 0.84, SECV = 0.54), crude protein ($R^2$= 0.96, SECV = 0.75), fat ($R^2$= 0.86, SECV = 0.54), crude fiber ($R^2$= 0.97, SECV = 0.63) and ashes ($R^2$= 0.86, SECV = 0.83). The sane set of spectroscopic data was used to predict the ingredient composition of the compound feeds. The preliminary results show that NIRS has an excellent ability ($r^2$$\geq$ 0, 9; RPD $\geq$ 3) for the prediction of the percentage of inclusion of alfalfa, sunflower meal, gluten meal, sugar beet pulp, palm meal, poultry meal, total meat meal (meat and bone meal and poultry meal) and whey. Other equations with a good predictive performance ($R^2$$\geq$0, 7; 2$\leq$RPD$\leq$3) were the obtained for the prediction of soya bean meal, corn, molasses, animal fat and lupin meal. The equations obtained for the prediction of other constituents (barley, bran, rice, manioc, meat and bone meal, fish meal, calcium carbonate, ammonium clorure and salt have an accuracy enough to fulfill the requirements layed down by the Common Position (EC Nº 6/2001). NIRS technology should be considered as an essential tool in food Safety Programs.

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A Integrated Model of Land/Transportation System

  • 이상용
    • 대한교통학회:학술대회논문집
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    • 대한교통학회 1995년도 제28회 학술발표회
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    • pp.45-73
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    • 1995
  • 토지이용규모와 교통수요의 크기, 그에 따른 혼잡정도를 이들간의 동적상호작용 올 시률레이션화하여 동시에 산출할 수 있는 시스템다이나믹스(System Dynamics)모델 이 제시된다. 이 모렐은 토지이용과 교통에 관계되는 물리적, 사회경제적, 정책적 변수들 간의 상호관계를 나타내는 다양한 함수와 피드백 루프(feedback loop)구조로 이루어져 있다. 전체모텔은 크게 인구, 인구이동, 가구변동, 부문별 고용 및 토지개발, 주택개발, 통 행수요, 혼잡레벨의 7개 서브모렐로 구성되며 각 서브모텔은 다시 부문별로 세분된다. 시스템다이나믹스모델의 주요 장점은 다음과 같다. 첫째, 토지이용과 교통시스템 올 둘러싼 복잡한 변수들 간의 동적 상호작용올 효과적으로 다룰 수 있으며 어떤 정책 에 대하여 시간적 변화에 따른 효과를 평가할 수 있다. 둘째, 시스템다이나믹스모텔은 시 블레이션에 의해 모텔의 결과가 산출되므로 종래의 모텔에서와 같이 토지이용과 교통체 계의 균형상태(equilibrium state)를 가정할 필요가 없다. 세번째로, 시스템다이나믹스모텔 은 다수의 분리된 수식(equations)으로 구성되므로 새로운 변수 -- 특정한 정책, 새로운 현상, 다른 방법론에 기초한 테크늬, 등 -- 들올 도입하기 쉽다. 논문의 앞부분(I, II, III장)에서는 모델의 전반적인 구조를 Causal Loop Flow D Diagram올 중심으로 논하고 있다. 구체적인 수식과 DYNAMO 프로그램, 모델계수의 추정 풍 기술적인 내용은 생략되었다. 이에 대하여는 저자의 박사학위논문을 참조하기 바란다 .. V장이 옹용부분으로서, 도로교통시설의 증대가 토지이용 및 교통수요, 그리고 교 통혼잡에 각 년도별로 어떻게 그 영향이 나타나는가를 메릴랜드의 Montgomery County 지역올 대상으로 검증하였다. 분석결과에 의하면, 도로용량중대의 교통유발효과 ( (Demand-inducing Effect)는 비 교척 낮은 것으로 나타났다. 또, 도로용량이 같더 라도 일 반도로보다 Freeway의 교통유발이 훨씬 큰 것으로 나타났다. 도로용량증대가 토지이용 에 미치는 효과를 보면 용량중대가 없었던 경우와 비교할 때 단기적으로는 차이가 거의 없으나 장기적으로는 큰 차이를 미치고 있다. (인구증가의 경우 도로시설올 설치하지 않 올 경우보다 4년후에는 8% 차이에 불과하나 19년후에는 15.5%의 차이를 보여주고 있다.) 이 논문은 다이나믹 시스템시율레이션올 이용하여 토지이용과 교통수요 및 혼잡 도 간의 상호작용을 종합적으로 다룬 첫번째 시도라 생각된다. 이 토지이용/교통모텔은 광범위한 규모를 다룬 매크로시률레이션모델로서 정교한 수준까지 발전시키려면 아직 많 은 후속작업이 필요할 것으로 보이지만, 현재까지의 결과로 볼 때 복잡한 토지이용과 교 통시스템을 종합적으로 다룰 수 있는 유력한 도구가 될 수 있올 것으로 평가된다.

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