• Journal of Biosystems Engineering
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• 제41권3호
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• pp.177-183
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• 2016

Purpose: Mee (Madhuca longifolia) is an economically important tree growing throughout Sri Lanka. Its importance is mainly attributed to its oil with high nutritional and medicinal values. However, an inefficient extraction method limits its use. This study revealed the possibility of extracting oil from mee seeds by using a screw-type oil expeller. Methods: A popular screw-type oil expeller was used in the experiment. Extract bar clearance and speeds of the main spiral shaft were altered to increase the oil expelling efficiency of the machine. The quality of refined oil at the optimum oil yield was determined by measuring the refractive index, saponification value, iodine value, unsaponifiable matter, free fatty acid, and specific gravity. Results: An optimum yield of 35% oil was obtained when the machine capacity was 30 kg/h and energy consumption was 0.13 kWh/kg. This optimum machine condition was observed at an extract bar clearance of 0.5 mm and a main spiral shaft speed of 90 rpm. The refractive index, saponification value, iodine value, unsaponifiable matter, free fatty acid, and specific gravity of the oil were 1.4, 203, 59, 3.5%, 0.2%, and 0.907 g/cm3 respectively. Color of the mee oil was closer to yellow, which is revealed by the lightness value (L) of 24.93 and positive value (b) of 11.81. Conclusion: The screw-type oil expeller can be used for economically extracting mee oil on a commercial scale.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.1513-1514
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• 2011

• 한국잡초학회지
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• 제13권1호
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• pp.7-13
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• 1993

농산물(農産物) 수입개방화(輪入開放化)에 대처(對處)하여 농가(農家) 고소득(高所得) 작물중(作物中) 하나인 참깨의 수확(收穫)시 기계화(機械化) 작업(作業)에 의한 노동(勞動)의 효율(效率)과 대량생산(大量生産)에 따른 생산비(生産費) 절감(節減)을 위한 방법(方法)으로 비선택성(非選擇性) 제초제(除草劑)인 paraquat와 diquat를 예취(刈取) 3일전(日前)과 3시간전(時間前)에 각각(各各) 처리(處理)하여 참깨 수확(收穫)을 위한 건조제(乾燥劑)로서의 이용가능성(利用可能性)을 연구(硏究)할 목적(目的)으로 수행(遂行)한 실험결과(實驗結果)는 다음과 같다. 1. Paraquat와 diquat를 예취(刈取) 3일전(日前)과 3시간전(時間前)에 각각(各各) 처리(處理)한 결과(結果) 참깨 꼬투리의 수분함량(水分含量)은 무처리구(無處理區)에 비(比)해 빠르게 감소(減少)되어 건조효과(乾燦效果)가 뚜렷하였다. 2. 공시약제(供試藥劑)를 처리(處理)한 후(後) 수확(收穫)한 참깨의 수량(收量)과 참깨 종자(種子)의 발아율(發芽率)은 무처리구(無處理區)에 비(比)하여 유의차(有意差)가 없었다. 3. 참깨 종자중(種子中)의 약제(藥劑) 잔유량(殘留量)은 두 공시약제(供試藥劑) 모두 예취(刈取) 3일전(日前) 처리농도(處理濃度) 250ppm에서 검출(檢出)되지 않았다. 4. 예취후(刈取後) 일수(日數)에 따른 참깨꼬투리의 탈립율(脫粒率)은 건조제(乾燥劑) 처리(處理)로 무처리(無處理) 실행(慣行)에 비(比)하여 매우 높았다. 5. 탈곡회수(脫穀回數)에 따른 소요노동력(所要勞動力)도 크게 감소(減少)되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권12호
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• pp.1729-1735
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• 2011

The effect of flaxseed meal on broiler performance, carcass characteristics, alpha-linolenic acid contents, and organoleptic characteristics of chicken meat was studied during a 42 day experiment. Broiler chicks were randomly allotted to 4 experimental groups and fed iso-energetic and iso-nitrogenous diets containing flaxseed meal at 0, 5, 10 and 15%. Flaxseed meal did not affect the weekly body weight of broiler chicks during the first two weeks but thereafter weekly body weight reduced among flaxseed meal groups. At the end of $6^{th}$ week, birds fed on 15% flaxseed meal showed a reduction of 8% in body weight compared to the control group. Control group had significantly higher weight gain with slightly higher feed consumption and better feed conversion ratio (FCR), protein efficiency ratio (PER), and energy efficiency ratio (EER) than the flaxseed meal groups. Among the treatments, birds of 5 and 10% flaxseed meal groups had significantly better FCR, PER and EER compared to those of the 15% flaxseed meal group. The carcass characteristics data indicated a significant reduction in the eviscerated weight and breast yield at 15% flaxseed meal in the diet as compared to other dietary groups. However, the alpha-linolenic acid content in both breast and thigh meat was higher with an increasing level of flaxseed meal in the diets without affecting the sensory acceptability of meat. Based on the present study, up to 10% of flaxseed meal may be used in broiler diet to enhance the alpha-linolenic acid content in the broiler meat.

• Journal of Communications and Networks
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• 제18권6호
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• pp.902-912
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• 2016

Recent advances in energy harvesting (EH) technology have motivated the adoption of rechargeable mobile devices for communications. In this paper, we consider a point-to-point (P2P) wireless communication system in which an EH transmitter with a non-ideal rechargeable battery is required to send a given fixed number of bits to the receiver before they expire according to a preset delay constraint. Due to the possible energy loss in the storage process, the harvest-use-and-store (HUS) architecture is adopted. We characterize the properties of the optimal solutions, for additive white Gaussian channels (AWGNs) and then block-fading channels, that maximize the energy efficiency (i.e., battery residual) subject to a given rate requirement. Interestingly, it is shown that the optimal solution has a water-filling interpretation with double thresholds and that both thresholds are monotonic. Based on this, we investigate the optimal double-threshold based allocation policy and devise an algorithm to achieve the solution. Numerical results are provided to validate the theoretical analysis and to compare the optimal solutions with existing schemes.

• Agribusiness and Information Management
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• 제3권1호
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• pp.11-22
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• 2011

This study describes the development of a web-based system that collects all data generated in the research conducted to set pre-harvest residue limits (PHRLs) for agricultural product safety control. These data, including concentrations of pesticide residues, limit of detection, limit of quantitation, recoveries, weather charts, and growth rates, are incorporated into a database, a regression analysis of the data is performed using statistical techniques, and the PHRL for an agricultural product is automatically computed. The development and establishment of this system increased the efficiency and improved the reliability of the research in this area by standardizing the data and maintaining its accuracy without temporal or spatial limitations. The system permits automatic computation of the PHRL and a quick review of the goodness of fit of the regression model. By building and analyzing a database, it also allows data accumulated over the last 10 years to be utilized.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2013년도 임시총회 및 하계학술연구발표회
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• pp.18-18
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• 2013

A FeRh alloy is a well-known efficient magnetocaloric material and some experimental and theoretical studies of bulk FeRh have been reported already by several groups. In this study we report first-principles calculations on magnetic properties of different thickness FeRh thin films in order to investigate the possibility to enhance further the magnetocaloric efficiency. We used Vienna Ab-initio Simulation Package (VASP) code. We found that the FeRh thin films have quite different magnetic properties from the bulk when the thickness is thinner than 6-atomic-layers. While bulk FeRh has a G-type antiferromagnetic (AFM) state, thin films which are thinner than 6-atomic-layers have an A-type AFM state or a ferromagnetic(FM) state. We will discuss possibility of magnetic phase transitions of the FeRh thin films in the view point of a magnetocaloric effect. And we found 4-, 5-, 6-layers films with Fe surface and 7-layers film with Rh surface are FM and they have dozens eV magnetocrystalline anisotropy (MCA) energy. MCA energy leads to determine energy barrier when magnetic states are changed by external magnetic field.

• 설비공학논문집
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• 제14권1호
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• pp.31-37
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• 2002

This paper is concerned with the development of a new method for making and separating ice and saving floated ice by installing an evaporation plate at in-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating a formed ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. A new harvest-type method shows very good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, but these components are not necessary in a new method. In this study two kinds of ice storage systems are experimentally investigated to study the thermal characteristics of ice storage tanks. The results showed discharge of cold capacity of new type indicated the high values about 30~40% based on five time of drive, the temperature difference of inlet/outlet occurred the big range about $1.3^{\circ}C$. So, the new type which makes ice in water showed superiorly.

• 에너지공학
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• 제25권4호
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• pp.184-189
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• 2016

$CO_2$ 배출 규제와 에너지 소비 절감의 요구가 늘어남에 따라, 버려지는 열을 수확하여 전기를 생산하기 위한 열전발전 연구가 최근 활발히 이루어지고 있다. 본 연구에서는 폐열 에너지 회수장치로 사용하기 위한 열전모듈의 발전 특성을 분석하였다. Bismuth telluride로 제작된 열전모듈에 다양한 온도 조건을 부여하며 이에 따른 열전 거동을 분석하였다. 또한 다양한 온도 조건에서의 열전모듈의 발전 효율을 실험 및 이론에 의해 분석하였다. 이로 부터, 열전모듈로 열에너지를 보다 효율적으로 회수하기 위한 최적의 작동조건을 제시하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.75.1-75.1
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• 2010

Dye sensitized solar cells(DSSCs) have been extensively studied due to their various advantages such as low production cost, colorful design, and eco-friendly process. Long optical path length is one of the most effective method to improve light harvest efficiency for DSSCs. Multi-layered $TiO_2$ nano-structured film with scattering layer has been studied to generate scattering effect by many researchers. It was expected that the difference of refractive index between $TiO_2$ particles and glass frit would generate the light scattering effect and provide the long optical path length. Therefore, to enhance the scattering effect, the frits of $Bi_2O_3-B_2O_3$-ZnO glass system that has the different refractive index were added to $TiO_2$ pastes in this study. First of all, the absorbance and haze factor of $TiO_2$ electrode with dyes and the refractive index of glass frit and $TiO_2$ were measured, respectively. To study the effect of frits, the efficiencies of DSSCs added glass frit and without glass frit were compared. Our results showed slightly higher efficiency with the different absorbance and haze factor of $TiO_2$ and glass frit. It was considered that the light scattering effect would be improved with adding frits to $TiO_2$ paste. Our preliminary studies will be useful for increasing efficiency of DSSCs.