• Biomolecules & Therapeutics
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• 제20권2호
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• pp.207-213
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• 2012

The present study examined the effects of krill-derived phosphatidylserine (Krill-PS) on the learning and memory function and the neural activity in rats with trimethyltin (TMT)-induced memory deficits. The rats were administered vehicle (medium-chain triglyceride: MCT) or Krill-PS (50, 100 mg/kg, p.o.) daily for 21 days. The cognitive improving efficacy of Krill-PS in TMT-induced amnesic rats was investigated by assessing the Morris water maze test and by performing choline acetyltransferase (ChAT), acetylcholinesterase (AChE) and cAMP responsive element binding protein (CREB) immunohistochemistry. The rats with TMT injection showed impaired learning and memory of the tasks and treatment with Krill-PS produced a significant improvement of the escape latency to find the platform in the Morris water maze at the $2^{nd}$ and $4^{th}$ day compared to that of the MCT group (p<0.05). In the retention test, the Krill-PS+MCT groups showed increased time spent around the platform compared to that of the MCT group. Consistent with the behavioral data, Krill-PS 50+MCT group significantly alleviated the loss of acetylcholinergic neurons in the hippocampus and medial septum compared to that of the MCT group. Treatment with Krill-PS significantly increased the CREB positive neurons in the hippocampal CA1 area as compared to that of the MCT group. These results suggest that Krill-PS may be useful for improving the cognitive function via regulation of cholinergic marker enzyme activity and neural activity.

• 한국항공운항학회지
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• 제22권3호
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• pp.68-73
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• 2014

Research is being carried out at Korea Aerospace Research Institute with aim of design a HALE UAV(High Altitude Long Endurance Unmanned Air Vehicle). HALE UAVs are ideally suited to provide surveillance, remote sensing and communication relay capabilities for both military and civilian applications. HALE UAVs typically cruise at an altitude between 15 km and 20 km, travelling at low speed and circling specific area of interest. Airframe structural point of view, weight reduction of the airframe structure is the most important method to improve the flight efficiency. High modulus CFRP(Carbon Fiber Reinforced Polymer) has been used in designing the structure in order to minimize the airframe weight. With respect to structural design and analysis, the key question is to decide an adequate airworthiness certification base to define suitable load cases for sizing of various structural components. In this study, FAR(Federal Aviation Regulation) 23 have constituted the guidance and benchmark throughout all structural studies. And the MSC/FlightLoads was introduced to analyze the flight loads for the HALE UAV. The MSC/FlightLoads can compute the flexible air load and analyzed loads are distributed on structural model directly. A preliminary structural concept was defined in accordance with the estimated inertial and aerodynamic loads. A FEM analysis was carried out using the MSC/Nastran code to predict the static and dynamic behaviour of UAV structure.

• 한국분무공학회지
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• 제25권1호
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• pp.27-33
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• 2020

NOx, PN and CO emissions from diesel trucks make up a significant portion of domestic air pollutant emissions. Therefore, test vehicles with various emission standards and driving modes were selected to evaluate the emission characteristics of regulated pollutants (NOx, PN, CO) in medium-duty trucks. As a result of test, all test vehicles were satisfied with Euro 5 or 6 regulation. NOx emissions of Euro 6 vehicles with after-treatment of LNT + DPF were lower than those of Euro 5 vehicles with DPF. In WLTC mode, all vehicles have high NOx emissions at section of extra high speeds, which are determined by increased fuel consumption and high combustion temperatures. CO and PN emissions from all vehicles were found to be low at section of low speeds. Also, The NO₂/NOx ratio was analyzed at 7-23% in each mode, and the NO₂/NOx ratio increased as the average vehicle speed increased. In NIER 9 mode, the CO, HC, and PN emissions were higher under cold conditions of engine than hot conditions of engine. In addition, vehicles with after-treatment system of LNT have similar NOx emissions level in this study.

• 한방비만학회지
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• 제15권2호
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• pp.104-110
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• 2015

Objectives: The herb of Agastache rugosa (AR) is a traditional herbal medicine used for colds, vomiting and furuncles. However, there are few reports to investigate the inhibitory effects of AR on obesity. In this study, the effects of AR on high fat diet (HFD)-induced obesity and its mechanism of actions were investigated in experimental animals. Methods: The mice were fed HFD for 4 weeks to induce obesity. After randomly divided into normal fat diet, HFD and AR groups, 200 mg/kg of AR was administrated for 4 weeks with continuous HFD feeding while vehicle was orally treated to HFD group. Food intake and body weight were recorded weekly. Results: Increased body weight by HFD was improved by AR treatment. AR administration inhibited an increase of visceral fat weight as well as adipocyte hypertrophy. Hepatic steatosis was ameliorated in AR-treated mice. In addition, treatment of AR attenuated the expression of adipogenic transcription factor, peroxisome proliferator-activated receptor (PPAR)-gamma in the epididymal adipose tissue. Also the increased serum leptin level by HFD was maintained in AR group, leading to inhibition of food intake. Conclusions: AR treatment showed inhibitory effects on HFD-induced obesity by inhibition of PPAR-gamma and reduction of food intake. AR could be an alternative treatment for obesity.

• Archives of Pharmacal Research
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• 제28권3호
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• pp.351-357
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• 2005

Endosulfan is one of the organochlorine pesticides, which are well-known endocrine disruptors (EDs), and it acts as an estrogen agonist. Estrogen is a group of hormones that play an important role in mammary gland function and are implicated in mammary carcinogenesis. In the present study, we studied the effects of endosulfan on nodule like alveolar lesion (NLAL) formation in mouse mammary gland development using a mouse mammary gland organ culture (MMOC) system. Although endosulfan-treated mammary glands did not form NLALs, more alveolar buds were formed in this group than in the negative control (vehicle-treated) group. In addition, telomerase reverse transcriptase (TERT) mRNA expression levels were increased in endosulfan-treated mammary glands in a dose-dependent manner. Telomerase can be activated by estrogen, therefore, we examined the effects of endosulfan on telomerase activity, and found that the telomerase activity in estrogen receptor-positive MCF-7 cells was up-regulated by endosulfan treatment. Moreover, this activation was accompanied by the up­regulation of the TERT mRNA expression. Also, transient expression assays using CAT reporter plasm ids containing various fragments of the TERT promoter showed that this imperfect palindromic estrogen-responsive element is almost certainly responsible for the transcriptional activation by endosulfan. These results may help elucidate the endocrine disrupting mechanism of endosulfan.

• 대한한의학회지
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• 제36권1호
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• pp.75-85
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• 2015

Objectives: Type 2 diabetes mellitus is a metabolic disease characterized by insulin resistance and high blood glucose level from progressive insulin secretory defect. The rhizome of Atractylodes japonica Koidz. (AJ) has been used for treatment of retention of water in oriental medicine. The aim of this study is to examine the effects of AJ on type 2 diabetes rats. Methods: Type 2 diabetes was induced by 60% high fat diet and low dose streptozotocin. Rats were divided into 4 groups (n = 6); Nor (normal control group), Con (diabetic group treated with vehicle), Met (diabetic group treated with 200 mg/kg metformin) and AJ (diabetic group treated with 100 mg/kg AJ). The body weights and food intakes were measured during the treatment period. After 4 weeks treatment, blood glucose level, HOMA-IR, and protein expressions of IRS-1, p-IRS-1, PPAR-${\gamma}$, and GLUT4 were measured, and histopathological examination of beta cell was performed. Results: Compared with the control group, blood glucose level and HOMA-IR were reduced in rats treated with AJ. Impaired beta cells in pancreas of rats were recovered and phosphorylation of IRS-1 was increased in rats treated with AJ. And also, protein expressions of PPAR-${\gamma}$ and GLUT4 were increased by treatment of AJ. Conclusions: The results suggest that Atractylodes japonica Koidz. may have anti-diabetic effect on type 2 diabetic rats through regulation of blood glucose level and insulin resistance. Therefore Atractylodes japonica Koidz. may have positive effects on patients with type 2 diabetes.

• 한국지리정보학회지
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• 제20권4호
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• pp.39-54
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• 2017

본 연구는 1998년부터 2010년까지 84개 시군에 대한 지하시설물 전산화가 완료되고 2011년부터 신규로 배관공사가 이루어지거나 기존관로 유지보수 갱신 배관공사에 대하여 2010년 개정된 국토지리정보원 고시 공공측량작업규정 제134호의 지하시설물도 작성시기에서 정확도 확보를 위하여 되메우기 전 노출관로에 대한 위치 및 심도측량으로 지하시설물도를 작성하게 되어있다. 실시간으로 작성하게 되어 있는 지하시설물도의 작성기법에 대하여 기존 방식과 대비 더욱 효율적이면서 부가가치가 높은 방식으로써 예산절감효과를 도출하여 현업에 적용 할 수 있는 응용기술을 모색하는데 그 목적이 있다. 최적화 된 드론영상자료를 기본으로 지상기준점 배치가 최대한 균등하게 분포되도록 이미지 프로세싱을 수행하여 오차범위에서 벗어난 지상기준점을 소거하고 재프로세싱 하여 양질의 성과를 도출함으로써 드론방식의 지하시설물도를 작성, 허용오차 범위 내에서 수용되는 검증결과를 수립하고, 프로세싱방법의 표준화가 될 수 있는 새로운 작업방법을 제시하고자 한다.

• 한국주거학회논문집
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• 제18권5호
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• pp.73-84
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• 2007

Permanent rental housing, the construction of which was strongly financed by the central government, is regarded as a social housing for those who fall within the lowest income bracket. Differing from "public rental housing", offered to tenants for sale after a five year rental period, this type of housing is intended for rental use on a long-tenn basis. At present, about 190,000 permanent rental housing units exist in Korea. According to a statistics, 15.6% of its residents did not pay their management fee and rental payment in 4 or more months in 2005, which places stress on the housing management. Based on the "eviction condition" stipulated in the tenancy agreement for permanent rental housing, a householder owning assets or a vehicle which is not used as his means of living, who is overdue with his management fee and rental payment for a long time, may be evicted from the house. However, there are many conflicts and problems between administrators/housing managers and residents in the process of enforcing this regulation. The purpose of this study is to explore the key issues associated with the present situation and the reasons why so many management fee and rental payment for permanent rental housing are overdue. For the purpose of research, data were collected from 10,990 permanent rental housing residents nationwide via a questionnaire survey in February 2007. One third of the respondents had an experience of more than 2 months overdue since they have moved in current residence. For further analysis, the respondents were divided into three groups, based on their working ability. The major finding showed that the group of respondents who have working ability required a more practical plan, such as employment, to have a sustainable life, while the other group of no labor force indicated a need for more housing allowance from the government. To suggest more specific alternatives for the subject of housing payment overdue, further comparison study should be performed between the residents of permanent rental housing and other low income tenants in private housing sector.

• 한국가스학회지
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• 제11권4호
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• pp.54-58
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• 2007

본 연구에서는 13L급 전자제어식 디젤 엔진을 혼소 엔진으로 개조하여 얻은 결과를 다루고 있다. 혼소 엔진 개조 후 차량의 출력, 연료경제성, 운전성 등을 파악하기 위하여 일정한 경로의 고속도로를 주행하였다. 개조된 차량은 최대 85%의 대체율을 가지며 500 km의 거리를 혼소 모드로 주행하였다. 차량의 주행성능은 디젤 모드의 경우와 거의 동일하였으나, 추월 가속성능이 약간 떨어지는 경향이 있었다. 엔진의 최대출력, 열효율, 배기가스 측정을 위하여 차량 시험과는 별도로 엔진 시험도 동시에 수행하였다. ND-13모드에서 배출가스 배출량 측정 실험을 수행한 결과, 산화촉매를 장착한 혼소모드에서의 배출가스 배출량은 디젤모드에서와 출력은 동일하게 유지하면서 K2006 규제를 만족함을 알 수 있었다.

• 한국전자통신학회논문지
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• 제7권6호
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• pp.1479-1485
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• 2012

주차관리 시스템은 주차장에서 주차 정보를 제공하여 운전자에게 주차의 편리성을 제공한다. 동시에 다수의 센서, 디스플레이와 제어모듈을 이용하여 아주 소량의 전기 에너지 만을 소모한다. 친환경 빌딩 설계의 요구가 점차 증가함에 따라 주차관리 시스템의 운용 전력 감축 문제가 이슈화 되고 있다. 본 논문에서는 주차관리 시스템의 감지기와 디스플레이 장치의 설계와 소비 전력 감축의 결과를 제시한다. 이 시스템은 무선 Park Tile 과 Park Disk를 사용하여 전력소비를 감축 시키고, 여러 개의 주차 공간 감지기와 자동차 카운터, 정보 디스플레이 장치, 안내 터미널과 제어장치로 구성되어 있다. 그리고 시스템구조 설계와 통신망 설계, 주차 정보 서비스 시나리오 계획, 배터리 수명 제어, 운영전력 평가 등이 수행되었다. 주차장당 운영전력은 0.93KW로 평가 되었으며, 이는 기존 시스템의 20%정도 이고 매년 유지비는 기존 시스템에 비해 18%에 해당된다.