• 한국항공우주학회지
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• 제36권4호
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• pp.384-392
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• 2008

위성의 전력계, 질량, 비용 등과 같은 형상 요소들의 개략적인 제원 도출은 본격적인 위성개발 전 반드시 수행되어야 할 중요한 과정이다. 본 논문에서는 최근 개발된 국내외 위성 개념설계 도구들의 주요한 특징들을 조사하고, 이를 바탕으로 초기 개념설계 절차를 정리하였다. 위성 개념설계는 탑재체와 임무에 근거하여 필요한 전력을 추정하고 위성운용에 필요한 태양전지판과 배터리와 같은 전력계를 추정한다. 다음으로 기존 위성들의 데이터베이스를 기반으로 탑재체질량에 따른 전체 위성 및 주요 서브시스템의 질량을 결정한다. 비용 역시 복잡한 계산 없이 기존 위성들의 데이터베이스를 바탕으로 대략적인 추정이 가능하다.

• 전기학회논문지
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• 제63권2호
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• pp.211-216
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• 2014

Construction of power plants and T&D facilities is so difficult because of the civil complaints and the additional cost according to the concerning field conditions. Therefore, various researches and methods have been considered to get solutions in the demand side and energy storage systems have been in the spotlight because of the various functions such as peak shaving, load shifting, and power system stabilizing, and so on. Residential small size batteries are considered in this paper and the economic analysis is carried out to evaluate the reasonable subsidy levels for the deployment of energy storage systems. Various economic parties are considered to find reasonable subsidy level comparing each other, which parties consist of utilities, participants and non-participants in general. The evaluation is based on California Standard Practice Test and the results are able to be used as subsidy guidelines.

• 보험의학회지
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• 제29권1호
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• pp.16-21
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• 2010

The measurement of prostate specific antigen (PSA) in screening for prostate cancer is recently performed as a routine check-up in clinical medicine and insurance medicine. Several factors may affect serum PSA levels. As prostate size increases with increasing age, the PSA concentration also rises. Increasing body mass index (BMI) is associated with a lower mean PSA concentration. Inhibitors of 5-alpha-reductase such as finasteride and dutasteride produce a 50 percent or greater decrease in serum PSA during the first three months of therapy, which persists as long as the drug is continued. Men who are regularly taking non-steroidal antiinflammatory drugs (NSAIDs) or acetaminophen have lower PSA levels. Emerging concepts regarding PSA testing that may help refine the interpretation of an elevated concentration include: PSA density, PSA velocity, and Free versus complexed or bound PSA. With many insurance companies, PSA level has become part of a standard battery of blood tests, along with HIV, cholesterol, liver enzymes, and other predictors of premature death. But, there is no clear proof of benefit, so we have to monitor the value of PSA test as a prostate cancer screening test in insurance medicine.

• The Journal of Asian Finance, Economics and Business
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• 제6권4호
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• pp.27-35
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• 2019

The paper examines the level of disclosure on Islamic banks' performance in the United Arab Emirates (UAE). The data was collected through content analysis of annual reports and financial statements of all fully-fledged Islamic banks working in the UAE over the period 2009 to 2013. Return on Assets is used as a proxy for the performance of Islamic banks while disclosure index is used as a proxy for Islamic banks' disclosure. Also, predetermined variables are used in the study like Size, Deposits, Non-Performing Investments and Capital to Risk Weighted Assets Ratio. Two-Stage Least-Square regression method is used to check the interdependence relationships between disclosure and performance of Islamic banks in the UAE. The results show a significant relationship between performance and disclosure in the UAE Islamic banks. Our regression results show that Islamic banks with higher levels of disclosure lead to higher operating performance. Furthermore, the performance has a great impact on the level of disclosure which means Islamic banks with high performance measures will disclose more information for investors and other institutions in order to reduce the cost of equity and increase their values in the market. This study is considered as a battery for further studies in the relationship between disclosure and financial performance of Islamic banks at a global level.

• Journal of Multimedia Information System
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• 제5권1호
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• pp.47-52
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• 2018

We have developed an electromagnetic generator to bury in subcutaneous area or abdominal cavity of the birds. As we can't use a solar battery, it is extremely difficult to supply a power for subcutaneous implantation such as biosensors under the skin due to the darkness environment. We are aiming to test the antigen-antibody reaction to confirm an avian influenza. One solution is a very small generator with the electromagnetic induction coil. We attached the developed coil to chickens and pheasants and recorded the electric potential generated as the chicken walked and the pheasant flew. The electric potential generated with physical simulator is equal to or exceeds the 7 V peak-to-peak at maximum by 560/min of flapping of wings. Even if we account for the junction voltage of the diode (200 mV), efficient charging of the double-layer capacitor is possible with the voltage doubler rectifier. If we increase the voltage, other problems arise, including the high-voltage insulation of the double-layer capacitor. For this reason, we believe the power generated to be sufficient for subcutaneous area of birds. The efficiency, magnetic 2 mm in length and coil 15mm in length, if axial direction is rectified, the magnetic flux density given to the coil could calculated to 7.1 % and generated power average 0.47mW. The improvements in size and wire insulation are expected in the future.

• 전력전자학회논문지
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• 제10권3호
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• pp.241-247
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• 2005

본 논문에서는 플라이휠의 저장에너지를 이용한 다이나믹 무정전 전원장치를 제안하고 동작기능을 분석하였다. 배터리를 에너지 저장요소로 사용하고 있는 기존의 무정전 전원장치에 비해 플라이휠 방식의 무정전 전원장치는 수명이 길고, 효율이 높으며, 환경공해가 거의 없으며, 크기도 작고, 특히 유지보수 비용이 현저히 작다는 장점을 갖는다. 무정전 기능뿐 아니라 전압보상 기능도 갖는 시스템에 대한 동작특성을 해석하였으며, 순간정전 후 전압이 복귀되는 시점에서의 위상변동을 신속히 추종하는 특성도 살펴보았다. 시뮬레이션과 실험을 통해서 시스템의 유용성을 검증하였다.

• 한국세라믹학회지
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• 제41권5호
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• pp.388-394
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• 2004

균일하게 혼합된 LiNO$_3$와 Co 금속분말을 알곤 분위기 하에서 SHS 공정으로 리튬이차전지용 양극활물질인 LiCoO$_2$분말을 합성하였다. 여러 가지 반응변수에 따라 제조된 분말의 특성과 전기화학적 특성평가를 수행하였는데, 반응온도 및 속도와 제조된 분말의 입도는 각각 Li/Co 몰비와 시료의 냉각속도 변화로 제어 가능하였다. Li/Co 몰비가 1.05일 때 최대방전용량인 145 mAh/g을 나타냈으며, 10회 충ㆍ방전 실험 후 6.4%의 낮은 용량감소를 갖는 비교적 안정된 cycling 특성을 보였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권12호
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• pp.6152-6168
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• 2017

Recently, the biometric-based authentication systems such as FIDO (Fast Identity Online) are increased in mobile computing environments. The biometric-based authentication systems are performed on the mobile devices with the battery, the improving energy efficiency is important issue. In the case, the size of images (i.e., face, fingerprint, iris, and etc.) affects both recognition accuracy and energy consumption, and hence the tradeoff analysis between the both recognition accuracy and energy consumption is necessary. In this paper, we propose an energy-efficient way to authenticate based on biometric information with tradeoff analysis between the both recognition accuracy and energy consumption in multimedia IoT (Internet of Things) transmission environments. We select the facial information among biometric information, and especially consider the multicore-based mobile devices. Based on our experimental results, we prove that the proposed approach can enhance the energy efficiency of GABOR+LBP+GRAY VALUE, GABOR+LBP, GABOR, and LBP by factors of 6.8, 3.6, 3.6, and 2.4 over the baseline, respectively, while satisfying user's face recognition accuracy.

• Asian-Australasian Journal of Animal Sciences
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• 제6권2호
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• pp.253-258
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• 1993

The study on the nutritive value and the potential use of two kinds (local vs. import) of sesame meal (SSM) in layer diets as substitute for soybean meal (SBM) at 25, 50, and 75% was carried out. Three hundred and thirty six layers were kept individually on a battery cage and fed isonitrogenous diets, 16% crude protein (CP), for 252 days. The local and the imported SSM contained on air dry basis 35.7 and 36.3% CP, 24.7 and 9.1% ether extract (EE), respectively. Their amino acid contents are all lower than those reported by NRC (1984). The local material contained remarkably lower lysine (0.44 vs. 0.94), methionine + cystine (1.06 vs. 1.75) and threonine (0.52 vs. 1.22) than the imported meal. Imported SSM could be substituted for SBM as high as 50% in layer ration without statistically adverse effect on egg production, feed intake, body weight gain, average egg weight and egg size, while local SSM was inferior to the control in all aspects. However, when production performance of the groups fed either kind of SSM was compared, no significant difference was found at the two lower substitution levels.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.125-128
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• 2007

In these recent years, low cost and stable battery electrode materials have been studied for HV/HEV application. Spinel cathode material $LiMn_2O_4$ is widely studied as a promising cathode material of lithium ion secondary batteries because of it is low cost, easily to be prepared and capable to be operated in high voltage range. In this study, $LiMn_2O_4$ was undergoing surface modification with spinel lithium titanium oxide by sol-gel method in order to enhance its capacity retention. Properties of both unmodified and surface-modified $LiMn_2O_4$ were characterized by XRD, SEM, particle size analyzer while their cycling performance was tested with charge and discharge tester.