• 한국유체기계학회 논문집
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• 제16권4호
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• pp.15-21
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• 2013

This study aims to estimate the fatigue resistance of small wind composite blade using the fatigue life estimation formula in the GL guideline. For this, firstly, we estimated a turbine blade's bending moment spectrum by using wind profile wind profile and BEMT. And fatigue tests were performed to obtain the S-N curve of composite materials used in blade. In addition, a finite element analysis was used to identify fatigue critical locations and fatigue stress spectrum. And the fatigue resistance of composite blade were evaluated using the rainflow cycle counting, and Goodman diagram and the fatigue life estimation formula in the GL guideline.

• 한국축산시설환경학회지
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• 제18권2호
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• pp.75-84
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• 2012

현재 우리나라 축산부문의 온실가스 배출량 계산은 1996년에 출판된 '1996년 IPCC 국가 온실가스 인벤토리 지침서 (1996 IPCC지침)'에 따라 계산하고 있으며 그 배출량 데이터는 국가 인벤토리 보고서에 사용하고 있다. 하지만 새로운 지침서, '2006년 IPCC 국가 온실가스 인벤토리 지침서 (2006 IPCC 지침)'가 2006년에 출판되었기 때문에 온실가스 배출량 계산을 위한 새로운 지침서를 적용하기 위한 준비가 필요하다. 본 연구에서는 축산에서 1996 IPCC 지침과 2006 IPCC 지침을 비교하였다. 또한 2000년부터 2008년 사이의 온실가스 배출량을 Tier 1 방법으로 계산하였다. 2006 IPCC 지침으로 계산한 온실가스 배출량은 1996 IPCC 지침을 이용할 때와 비교하여 1.27~1.33배 더 많았다. 이는 배출계수의 차이에 의한 것으로 나타났다. 국가 온실가스 인벤토리의 불확실성을 감소시키기 위해 더 많은 연구가 필요하다.

• 한국소음진동공학회논문집
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• 제24권5호
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• pp.363-373
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• 2014

In this study, computational multi-body dynamic analyses for the drivetrain system of a 5 MW class offshore wind turbine have been conducted using efficient equivalent modeling technique based on the design guideline of GL 2010. The present drivetrain system is originally modeled and its related system data is adopted from the NREL 5 MW wind turbine model. Efficient computational method for the drivetrain system dynamics is proposed based on an international guideline for the certification of wind turbine. Structural dynamic behaviors of drivetrain system with blade, hub, shaft, gearbox, supports, brake disk, coupling, and electric generator have been analyzed and the results for natural frequency and equivalent torsional stiffness of the drivetrain system are presented in detail. It is finally shown that the present multi-body dynamic analysis method gives good agreement with the previous results of the 5 MW class wind turbine system.

• Journal of Biosystems Engineering
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• 제40권4호
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• pp.305-313
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• 2015

Purpose: This study was performed to predict the fatigue life of a crank-type rotavator operated in domestic soil conditions using Recurdyn$^{(R)}$, a dynamic analysis program. Methods: Torque on the PTO shaft was measured using experiments conducted on the uplands and paddy fields in Korea. On the basis of the experimental and analytical results, the fatigue life of the crank-type rotavator was predicted by constructing an S-N curve according to the GL (Germanischer Lloyd Wind Energie GmbH) guideline. Results: The torques experienced by the PTO shaft in the paddy soil and the uplands were in the range of 472~797 N m and 313~430 N m, respectively, for every condition. In case of load condition, the peak torques (846 N m, 770 N m) were applied for severe conditions, resulting in a maximum (von Mises) stress of 75 MPa at the crank arm. The fatigue life of the crank-type rotavator was predicted to be 1,167 h that satisfies the target value of 1,110 h, by substituting the analysis results into an S-N curve of crank arm. Conclusions: The fatigue life of the crank-type rotavator was within the target life for the studied soil conditions; however, further field experiments for various soil conditions would be required to verify the prediction results.

• 농촌계획
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• 제23권2호
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• pp.75-86
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• 2017

IPCC Guidelines have been updated after the first official announcement to get more precise estimation of GHG emissions. The goal of this study is to evaluate the implications of the IPCC Guidelines improvements including equations of country-specific parameter values for estimating GHG emissions for rice cultivation on the agricultural sector. In addition, we analyze the effects of emission factors associated with organic amendment applications. The results of this study are as follows; (1) the total GHG emissions of rice cultivation based on 1996 IPCC GL are 28% lower than those estimated by 2006 IPCC GL with the same year data; (2) GHGs can be reduced up to 60% through the assumption of organic fertilizer applications; (3) Jeonnam and Chungnam are the worst regions for GHG emissions on rice cultivation and Chungbuk shows the highest reduction rate of GHG emissions, about 40%.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.331-334
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• 2007

Wind turbine is composed by 3 major parts, rotor ass'y, nacelle ass'y and tower. There are two major point in nacelle cover analysis one is nacelle cover itself the other is cover support structure. Both of them are required strength proof with light weight. For the design of structure, the loads are calculated according to GL wind guideline Ed. 2003 and by the commercial F.E. codes,

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.295-298
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• 2008

The major function of the nacelle cover is protecting the inside equipments. Therefore, it is required not only sufficient strength and stability but also light weight. In this paper, design loads are calculated according to the GL Wind guideline Ed. 2003. To ensure the structural safety, a composite structure is selected. The structural design is processed by two steps which are preliminary design and detail design. In the preliminary design step, a structural analysis is performed with initial thickness, 5mm. As reviewing above analysis results, weak regions of the nacelle cover reinforced using the spar cap structure which is same as the blade structure. In the analysis model, the support structure is connected with the nacelle cover and analyzed its structural safety at the same time.

• 풍력에너지저널
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• 제5권1호
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• pp.43-49
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• 2014

Primarily, tower loads of a wind turbine arise from aerodynamic effect and a top head mass. But sometime asymmetric loads of rotor also affect on the tower loads. Especially ice formation on two blades out of three causes the asymmetric loads, because the ice formation on blades lead to large rotating mass imbalance. This rotating mass imbalance of rotor affects tower fatigue loads. So design load cases of ice formation on blade should be considered in the fatigue design loads of the tower according to GL guideline 2010. This paper describes the change of tower fatigue loads following increase of tower height in the condition of ice formation. Finally, the optimal operation strategy is examined in order to reduce tower fatigue design loads.

• 융합정보논문지
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• 제11권2호
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• pp.107-116
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• 2021

본 연구에서는 동물식품 내 잔류하는 동물의약품 중 성장보조제인 에스트라디올(Estradiol-17��), 테스토스테론(Testosterone), 프로게스테론(Progesterone)에 대한 분석법을 개발하고자 하였다. 분석대상 물질은 액체크로마토그라피를 사용하여 분리하였고, electrospray ionization(ESI) 과정을 거쳐 질량분석기에 주입되어 multiple reaction monitoring(MRM) 모드로 검출하였다. 개발된 분석법은 CODEX CAC/GL 71-2009에 근거하여 유효성을 검증하였고, 분석의 실효성 허용범위를 충족함을 확인하였다. 국내 유통되는 소고기, 돼지고기, 닭고기에 대해 확립된 분석법으로 분석을 진행하여 실제시료 적용성을 확인하였다. 이를 통해 개발된 분석법이 국내 유통 축산물에서 확인되고 있는 성장보조제 일부에 대해 신속하고 신뢰성 높은 분석이 가능함을 확인하였다. 후속 연구를 통해 확립된 분석법을 기반으로 분석대상 성장보조제의 범위를 확장하고, 이를 모두 포함시켜 동시분석법을 확립한다면 활용성이 높은 분석법이 완성될 것으로 확신한다.

• 한국환경농학회지
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• 제38권4호
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• pp.321-331
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• 2019

BACKGROUND: Pinoxaden is the phenylpyrazoline herbicide developed by Syngenta Crop Protection, Inc. and marketed on 2006. The maximum residue levels for wheat and barley were set by import tolerance. Thus, Ministry of Food and Drug Safety (MFDS) official analytical method determining Pinoxaden residue was necessary in various food matrixes. Satisfaction of international guideline of CODEX (Codex Alimentarius Commission CAC/GL 40) and National Institute of Food and Drug Safety Evaluation-MFDS (2017) are additional pre-requirements for analytical method. In this study, liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was investigated to analyze residue of Pinoxaden (M4), which is defined as pesticide residue in Korea, in foods. METHODS AND RESULTS: Pinoxaden (M4) was extracted followed by acid digestion (2hr reflux with 1N HCl) and pH adjusting (pH 4-5 with 3% ammonium solution). To remove oil, additional clean-up step with hexane saturated with acetonitrile was required to high oil contained sample before purification. HLB cartridge and nylon syringe filter were used for purification. Then, samples were analyzed by LC-MS/MS using reserve phase column C₁₈. Five agricultural group representative commodities (mandarin, potato, soybean, hulled rice, and red pepper) were used to verify the method in this study. The liner matrix-matched calibration curves were confirmed with coefficient of determination (r²) > 0.99 at calibration range 0.002-0.2 mg/kg. The limits of detection and quantitation were 0.004 and 0.01 mg/kg, respectively, which were suitable to apply Positive List System (PLS). Mean average accuracies of pinoxaden (M4) were shown to be 74.0-105.7%. The precision of pinoxaden and its metabolites were also shown less than 14.5% for all five samples. CONCLUSION: The method investigated in this study was suitable to CODEX (CAC/GL 40) and National Institute of Food and Drug Safety Evaluation-MFDS (2017) guideline for residue analysis. Thus, this method can be useful for determining the residue in various food matrixes in routine analysis.