• 토지주택연구
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• 제7권3호
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• pp.131-136
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• 2016

이 연구에서는 선행 연구에서 개발된 진동과 압력을 병합한 하이브리드 에너지하베스팅 블록의 성능을 개선하였다. 이와 같이 개선된 에너지블록의 발전 성능을 측정하고 앞서 개발된 제품들과의 에너지성능을 비교 분석하였다. 이전 모델에서는 중앙부에 압전체, 그리고 양측면에 진동인가형 전자기유도부를 배치했었다. 개선모델은 하나의 블록에 세 개의 단위모듈을 연속으로 배치하였다. 하나의 단위모듈의 상부에는 압전체를, 하부에는 세 개의 전자기부를 두는 방식으로 설계 변경하였다. 이와 같이 개선된 에너지블록에 대한 실험실 조건에서의 발전성능 평가결과, 1회 연속 가신 시에는 1.066W로 선행 대비 235%, 5회 연속 가진 시에는 1.830W로 선행대비 177%의 성능개선 효과를 얻을 수 있었다. 하이브리드 에너지블록의 개발목적은 주차장 출입부에 설치하여 차량이 에너지블록을 통과할 때 압력과 진동에 의해 전기를 생산하고자 하는 것이다. 이때 생산되는 전기는 주차장 출입구에 경광등과 LED 안내전광판 가동용으로 활용하고자 하는 것이다. 따라서 향후 실제 주차장에 설치를 통한 실험실조건과 실제조건에서의 발전성능을 검증할 필요가 있을 것으로 사료된다.

• 한국발생생물학회지:발생과생식
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• 제13권4호
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• pp.341-351
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• 2009

대하, Fenneropenaeus chinensis의 난소 성숙에 대한 serotonin(5-hydroxytryptamine, 5-HT), ecdysone(20-hydroxyecdysone, 20-E) 그리고 HCG(human chorionic gonadotropin)의 효과를 조사하였다. 대하에 5-HT(체중 g당 $5{\mu}g,\;20{\mu}g$), 20-E(체중g당 $5{\mu}g,\;10{\mu}g,\;20{\mu}g$) 그리고 HCG(체중 g당 5 IU, 10 IU)를 5일 간격으로 3회 주사한 후 10일이 더 지난 시점에 채집하여 성 성숙도지수(GSI)의 변화와 난소의 조직학적 변화를 조사하였다. 호르몬제의 효과를 비교하기 위해 멸균한 생리식염 수만을 주사한 대조구와 아무 것도 처리하지 않은 무처리구를 설정하였다. 20-E와 HCG를 처리한 실험구에서는 난소 성숙 효과가 전혀 나타나지 않았으나, 이른 봄에 5-HT를 체중 g당 $20{\mu}g$로 처리한 실험구에서는 유의한 난소 성숙효과를 보였다. 본 실험 결과에서 대하에 5-HT를 체중 g당 $20{\mu}g$ 이상 처리하면 난소성숙을 유도할 수 있다는 것을 보여주었으며, 이는 대하의 종묘 생산에 유용하게 사용될 수 있을 것이다.

• 한국대기환경학회지
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• 제22권5호
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• pp.574-589
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• 2006

Although concentrations of hazardous air pollutants(HAPs) are very low in the atmosphere, a growing attention has been paid on such compounds due to their high toxicity and bioaccumulation potentials into human body. In order to control and manage the amount of these materials in ambient air, it is necessary to construct monitoring system of them and to know the current concentration level of HAPs above all. In this work, a wide range of HAPs has been measured in metropolitan area to recognize the present state of HAPs in this area. The measured concentration of VOCs was higher in order of Jeonnongdong, Jeongdong, and Yangsuri. The regional difference of VOCs concentration was also highest in spring. Its total VOCs was ranged from $15.17{\sim}41.45$ ppb. Benzene $0.43{\sim}2.32$ ppb showed similar concentration level with the result of previous researches in Seoul. This value is a little higher than the average concentration 0.92 ppb for national ambient air quality standards in Japan. The concentration of aldehydes in this study was lower than those of other researches. Previous works in Seoul metropolitan area showed that the concentration of formaldehyde and acetaldehyde were higher than 5 ppb. The concentration of gaseous and particulate PAHs was high in order of winter, spring, and summer More than 90% of PAHs with low molecular weight such as 2-rings and 3-rings PAHs existed in gas phase. On the other hands, PAHs with high molecular weight more than 5-rings PAHs almost existed in particulate. In spring, the concentration of gaseous PAHs was 24.38 $ng/m^3$ in Jeongdong. Among the particulate PAHs, the concentrations of Naphthalene, Benzo(b)fluoranthene, and Benzo(g, h, i)perylene were higher than others. Especially, the concentration of Benzo(a)pyrene, a important carcinogenic pollutant, was highest in winter 0.5 $ng/m^3$ and ranged from 0.03 to 0.3 $ng/m^3$ in spring and summer, which is lower than the monitoring result in 90's. These components were mainly originated from the vehicle exhaust or heating equipment use.

• 한국축산식품학회지
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• 제40권5호
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• pp.795-812
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• 2020

Novel food sources have enormous potential as nutritional supplements. For instance, edible insects are considered as an alternative food source due to their higher protein content; moreover, they are economically efficient reproducers and have high in nutritional value. In this study, we investigated the toxicity of the freeze-dried powder of Locusta migratoria (fdLM), known to contain rich proteins as well as fatty acids. The objective of the present study was to evaluate the subacute toxicity of fdLM in male and female Sprague-Dawley (SD) rats. The SD rats were divided into four groups based on the dosage of fdLM administered: dosage of 0 (vehicle control), 750, 1,500, and 3,000 mg/kg/day were administered for 28 days. Toxicological assessments including observations on food consumption, body and organ weights, clinical signs, mortality, ophthalmologic tests, urinalyses, hematologic tests, clinical chemistry tests, gross findings, and histopathology tests were performed. Clinical signs, urinalyses, hematology, serum biochemistry tests, and organ weight examinations revealed no fdLM-related toxicity. The no-observed-adverse-effect level for fdLM was higher than 3,000 mg/kg/day in rats of both sexes; therefore, fdLM, in conclusion, can be considered safe as an edible alternative human and animal food source material.

• Journal of Periodontal and Implant Science
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• 제38권1호
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• pp.59-66
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• 2008

Purpose: It has been shown that the inorganic polyphosphate is effective for the regeneration of bones through the preliminary animal test of rabbits. The most effective concentration of the polyphosphate, however, is not known yet. Moreover, the effectiveness of carriers inside human body is not confirmed.. Materials and Methods: In this study, we examined the effect of the concentration of the inorganic polyphosphate on the process of the bone regeneration using the 6 weeks old rabbits with the weight of 2.0 kg in average. We performed the experiment using TR-ePTFE membrane(membrane) filled with collagen immersed in 4%, 8% of inorganic polyphosphate, respectively, following removal of the proper sized cortical bones from the rabbit calvaria. The experimental results were compared with the one of the following four groups: The negative control group for membrane only, the positive control group for membrane filled with collagen, the first experimental group for membrane filled with collagen immersed in 4% of inorganic polyphosphate, and the second experimental group for membrane filled with collagen immerse in 8% of inorganic polyphosphate. The fragments of the tissue with membrane obtained from each group of the sacrificed rabbits for 8 or 16 weeks sustained after surgery were then prestained by the Hematoxylin-Eosin stain and coated by resin to form non-decalcified specimens for the histologic examination and analysis. New bone formation was assessed by histomorphometric and statistical analysis. Results: 1. All groups have shown better bone regeneration at 16weeks than 8weeks. 2. Negative control group has shown more bone regeneration relative to the other groups at 8 and 16 weeks. 3. All experimental groups have shown better bone regeneration relative to positive control group. 4. At 16 weeks, the first experimental group has shown more bone regeneration compared to the second experimental group. Exophytic bone formation is not good at the first and the second experimental groups compared with negative control group. But, the use of 4% inorganic polyphosphate was more effective to bone formation than the use of 8% inorganic polyphosphate. Conclusion: With above results, it is suggested the use of inorganic polyphosphate with vehicle under TR-ePTFE membrane.

• Restorative Dentistry and Endodontics
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• 제17권1호
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• pp.10-21
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• 1992

The purpose of this study was to investigate the analgesic effect of eugenol, capsaicin and demethoxy-NE. Young adult cats, weighing 2.0 to 3.0kg, were used. Each animal was anesthetized (${\alpha}$-chloralose 60mg per kg body weight) and divided into four groups; control, eugenol, capsaicin and demethoxy-NE group. The anterior digastric muscles were exposed and a pair of electrodes was inserted to record the electromyograms. To expose the pulp, each canine teeth was prepared with a low speed bur under cooling and used for recording anterior digastric muscular EMGs evoked by noxious stimulation of dental pulp. To observe effects on jaw opening reflex, inferior alveolar nerve of both sides were exposed for drug application and wire electrodes were inserted in anterior digstric muscle for recording the EMGs. To observe effects on action potential, saphenous nerves of both sides were exposed and three tissue pools were made from surrounding tissue. The most distal pool was used for applying stimulation, the most proximal one for recording of action potential, and the other one for drug application. One side of inferior alveolar nerve and saphenous nerve were used for eugenol, capsaicin, or demethoxy-NE application, the other side of nerve for control experiments(only vehicle application). Anterior digastric muscular EMGs evoked by noxious stimulation of dental pulp were recorded before drug application, immediate after drug application, at 60 and 120 minutes, and 5 days after drug application. Action potentials were recorded before drug application, immediate after 30 minutes drug application, at 30, 60 and 120 minutes after drug had been washed out. The results were as follows; 1. Eugenol had a continuous blocking effect on the anterior digastric muscular EMGs evoked by noxious pulp stimulation and after 5 days, showed completely blocking effect. 2. After 5 days, demethoxy-NE applied to dental pulp had a considerable blocking effect on the jaw opening retlex evoked by noxious stimulation but capsaicin had no significant effect. 3. After 5 days, eugenol group showed the strongest blocking effect among the all experimental groups on the jaw opening reflex evoked by noxious stimulation of dental pulp and capsaicin group showed the weakest blocking effect. 4. Eugenol had a completely blocking effect on the action potential conductivity of peripheral nerve. Capsaicin and demethoxy-NE had the blocking effect on the action potential conductivity of ${\alpha}$-and C-nerve fibers. 5. Capsaicin, demethoxy-NE and eugenol applied to inferior alveolar nerve surppressed the jaw opening reflex evoked by noxious stimulation of dental pulp.

• 한국식품영양과학회지
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• 제45권3호
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• pp.313-320
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• 2016

본 연구에서는 라벤더, 캐모마일, 레몬버베나, 타임, 바질의 복합 열수 추출물이 수면을 촉진하고 스트레스를 완화하는지 확인하기 위하여 농도에 따라 동물모델에 미치는 효과를 관찰하였다. 허브 복합추출물(HME)을 10, 30, 100 mg/kg의 농도로 3주간 구속 스트레스 모델과 수면장애 모델에 각각 경구투여 하였고, 실험 결과 구속 스트레스를 유도한 동물모델에서 HMEII군(30 mg/kg)과 HMEIII군(100 mg/kg)은 혈장 내 코티졸과 IL-6 함량을 감소시켰으며, HMEIII군은 체중 대비 부신 무게도 유의적으로 회복시킨 것을 확인하였다. 수면장애 모델에서는 HMEIII군이 대조군에 비해 체중이 증가하였고, HME II, III군은 혈장 내 멜라토닌 수치를 높였으며 코티졸 수치를 감소시켰다. 이러한 결과를 통해 본 실험에서 사용한 허브 복합추출물이 농도에 따라 스트레스 완화와 수면장애 개선에 효과가 있음을 확인하였다.

• 대한한방부인과학회지
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• 제30권3호
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• pp.1-19
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• 2017

목 적: 본 연구는 녹용대보탕이 안와정맥총 방혈로 유발시킨 랫트의 아급성 출혈성 빈혈 모델에 대해 항빈혈 및 조혈촉진 효과를 확인하였다. 방 법: 본 실험에서는 안와 정맥총에서 혈액을 채혈하여 아급성 출혈성 빈혈을 유발시켰으며, 녹용대보탕 추출물을 경구투여하고, 체중 및 조혈 관련 장기(대퇴골 골수, 비장 및 간) 중량, 적혈구 관련 혈액학적 지표의 변화, 혈액 도말 표본의 세포학적 변화, 조혈관련 장기의 조직병리학적 변화와 함께 조혈장기 내 혈구형성 줄기세포의 수적 변화를 면역조직화학적으로 관찰하였다. 또한 철분 보충제의 대표적 부작용인 소화 장애, 특히 변비 유발 여부를 확인하기 위해 탄분을 이용해 위장관 운동성을 평가하였으며, 결장내 분변 표면의 점막 두께와 결장점막 내 점액생산세포 및 결장 점막 두께 변화를 조직병리학적으로 평가하였다. 결 과: 본 실험에서 유발된 아급성 출혈성 빈혈 소견이 모든 세 용량의 녹용대보탕 추출물의 용량 의존적으로 현저히 억제되었다. 또한 세 용량의 녹용대보탕 투여군에서는 정상 대조군 및 아급성 출혈성 빈혈 대조군에 비해 위장관 운동성 변화 및 결장 및 결장내 분변의 점액성분의 유의미한 변화는 없었다. 결 론: 이상의 결과에서, 녹용대보탕의 경구투여는 아급성 출혈성 빈혈 유발 랫트에서 단순 철분 보충제의 부작용인 소화관 장애 없이, 조혈관련 장기들에서 혈구형성줄기세포의 증식 촉진을 통해 투여 용량 의존적으로 철 결핍성 빈혈의 증상을 현저히 완화시키는 것으로 관찰되었다. 따라서 녹용대보탕은 새로운 개념의 조혈촉진 빈혈치료제로서의 개발 가치가 충분할 것으로 판단된다.

• 한국산학기술학회논문지
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• 제19권11호
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• pp.561-567
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• 2018

본 연구는 동력분산형 고속열차의 승차감을 개선하기 위하여 진행되었다. 동력분산형 고속열차 시제차량의 동역학 해석을 통해 300km/h이상의 임계속도를 갖는 등가 답면구배의 범위는 0.05에서 0.25사이임을 확인하였다. 초기에 적용된 차륜 프로파일 S1002는 4만km이상의 누적주행거리에도 불구하고 등가 답면구배는 0.033 정도였고, 안정적인 운행을 위해서는 등가 답면구배가 0.061이 넘는 XP55가 더 적합함을 확인하였다. 동력분산형 고속열차의 승차감을 개선하기 위한 방안으로 요댐퍼의 설치 각도를 $7.35^{\circ}$에서 $0^{\circ}$로 변경하고, 민감도 분석과 최적화를 통해 도출된 공기스프링 횡 및 상하방향 강성 30% 감소, 2차 수직댐퍼 및 횡댐퍼 댐핑계수를 50% 증가시키는 방안을 제안하였다. 이를 적용하면 차체 가속도를 평균 20%정도 개선시킬 수 있을 것으로 예상되었다. 도출된 승차감 개선 방법의 일부인 요댐퍼 설치각도를 $0^{\circ}$로 변경하고 횡댐퍼의 댐핑계수를 30% 증가시킨 후 경부고속선에서 300km/h 속도로 시운전을 진행하였을 때, 차체 횡가속도는 평균 34.3% 개선되었고, 본 연구에서 제안된 추가적인 개선 방안은 향후 시운전 시험 시에 적용될 예정이다. 본 연구에서 사용된 승차감 개선 프로세스는 향후 동력분산형 고속열차의 상업 운행 시에 발생할 수 있는 승차감 관련 문제 해결에 사용될 수 있다.

• 한국해양공학회지
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• 제33권2호
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• pp.168-177
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• 2019

KRISO (Korea Research Institute of Ship & Ocean Engineering) started a project to develop the core algorithms for autonomous intervention using an underwater robot in 2017. This paper introduces the development of the robot platform for the core algorithms, which is an ROV (Remotely Operated Vehicle) type with one 7-function manipulator. Before the detailed design of the robot platform, the 7E-MINI arm of the ECA Group was selected as the manipulator. It is an electrical type, with a weight of 51 kg in air (30 kg in water) and a full reach of 1.4 m. To design a platform with a small size and light weight to fit in a water tank, the medium-size manipulator was placed on the center of platform, and the structural analysis of the body frame was conducted by ABAQUS. The robot had an IMU (Inertial Measurement Unit), a DVL (Doppler Velocity Log), and a depth sensor for measuring the underwater position and attitude. To control the robot motion, eight thrusters were installed, four for vertical and the rest for horizontal motion. The operation system was composed of an on-board control station and operation S/W. The former included devices such as a 300 VDC power supplier, Fiber-Optic (F/O) to Ethernet communication converter, and main control PC. The latter was developed using an ROS (Robot Operation System) based on Linux. The basic performance of the manufactured robot platform was verified through a water tank test, where the robot was manually operated using a joystick, and the robot motion and attitude variation that resulted from the manipulator movement were closely observed.