• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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• pp.230-234
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• 2009

It is significant technique to increase competitiveness that solar cells have a high energy conversion efficiency and cost effectiveness. When making high efficiency crystalline Si solar cells, evaporated Ti/Pd/Ag contact system is widely used in order to reduce the electrical resistance of the contact fingers. However, the evaporation process is no applicable to mass production because high vacuum is needed. Furthermore, those metals are too expensive to be applied for terrestrial applications. Ni/Cu/Ag contact system of silicon solar cells offers a relatively inexpensive method of making electrical contact. Ni silicide formation is one of the indispensable techniques for Ni/Cu/Ag contact sytem. Ni was electroless plated on the front grid pattern, After Ni electroless plating, the cells were annealed by RTP(Rapid Thermal Process). Ni silicide(NiSi) has certain advantages over Ti silicide($TiSi_2$), lower temperature anneal, one step anneal, low resistivity, low silicon consumption, low film stress, absence of reaction between the annealing ambient. Ni/Cu/Ag metallization scheme is an important process in the direction of cost reduction for solar cells of high efficiency. In this article we shall report an investigation of rapid thermal silicidation of nickel on silngle crystalline silicon wafers in the annealing range of $350-390^{\circ}C$. The samples annealed at temperatures from 350 to $390^{\circ}C$ have been analyzed by SEM(Scanning Electron Microscopy).

• 제어로봇시스템학회논문지
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• 제21권5호
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• pp.393-400
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• 2015

This paper describes the development of a chest-wearable robot that can efficiently perform self walking rehabilitation without a helper. The features of the developed robot are divided into three parts. First, as a mechanical characteristic, the conventional elbow crutch is attached at the forearm. However, the proposed robot is attached to the patient's chest, enabling them to feel free to use their hands and eliminate the burden of the arms. Second, as a characteristic of the driving algorithm, pressure sensors attached to the chest automatically perceive the patient's walking intention and move the robot-leg thereafter. Also, for safety, it stops operating when an obstacle is found in front of the patient by using ultrasonic sensors and generates a beeping sound. Finally, by using the scotch yoke mechanism, supporting legs are moved up and down using a rotary servo motor without excessive torque that is generated by large ground reaction forces. We showed that the developed robot can effectively perform self walking rehabilitation through walking experiments, and its performance was verified using Electromyograph (EMG) sensors.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.267-273
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• 2012

Solar reforming of methane with CO2 was successfully tested with a direct irradiated absorber on a parabolic dish capable of 5kWth solar power. And the new type of double-layer absorber-the front layer, porous metal foam which absorbs the radiation and transfers the heat from material to gas, and the back layer, catalytically-activated metal foam-was prepared, and its activity was tested by using electric furnace. Ni was applied as the active metal on the gamma-Al2O3 coated Ni metal foam for the preparation of the catalytically-activated metal foam layer. Compared to conventional direct irradiation of the catalytically activated metal foam absorber, this new type of double layer absorber is found to exhibit a superior reaction and thermal storage performance at the fluctuating incident solar radiation. In addition, unlike direct irradiation of the foam absorber, double layer absorber has better thermal resistance, which prevents the emergence of cracks caused by mechanical or thermal shock. The total solar power absorbed reached up to 3.25kW and the maximum CH4 conversion was almost 59%.

• 재활복지공학회논문지
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• 제9권1호
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• pp.67-72
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• 2015

팔의 사용이 자유롭지 못한 장애인들을 위하여 발의 움직임 검출을 통하여 로봇 팔을 제어할 수 있는 시스템을 구현하였다. 발의 움직임에 대한 영상을 얻기 위하여 양쪽 발 앞에 두 대의 카메라를 설치하였으며, 획득된 영상에 대해 LabView 기반 Vision Assistant를 이용하여 다중 관심영역을 설정한 후, 좌/우영역내에서 검출된 좌/우, 상/하 엣지를 기반으로 발의 움직임을 검출하였다. 좌/우 두발의 영상으로부터 좌/우 엣지와 상/하 엣지 검출 수에 따라 6관절 로봇 팔을 제어할 수 있는 제어용 데이터를 시리얼 통신을 통해 전송한 후 로봇 팔을 발로 상/하, 좌/우 제어할 수 있는 시스템을 구현하였다. 실험 결과 0.5초 이내의 반응속도와 88% 이상의 동작 인식률을 얻을 수 있었다.

• 한국운동역학회지
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• 제22권1호
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• pp.17-24
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• 2012

This study is for providing fundamental data of sport biomechanics in GRF & plantar pressure of stepping foot of skilled & unskilled players' at the soccer instep shooting moments. Wearing Pedar-x of Novel, the study has drawn the following conclusion after measuring and analyzing the impact on the GRF and plantar pressure of stepping foot at the instep shooting moments. First, maximum vertical GRF showed higher in the skilled group than in the unskilled group. The results showed significantly different. This study reached the conclusion that the players in the skilled group performed faster and stronger stepping foot motions that the ones in the unskilled(p<.01). Second, since the plantar pressure of the skilled group appeared significantly higher than that of the unskilled, it has brought us to the conclusion that the skilled group performed faster and stronger stepping foot motions than the unskilled group (p<.05). Third, at the moment of instep kicking, the skilled group's average maximum plantar foot pressure of stepping foot was higher than the unskilled. Though the difference was not statistically significant, it can be concluded that the skilled group performed faster and stronger stepping foot motions than the unskilled group(p>.05). Fourth, for the COP moving route of stepping foot while instep kicking, the skilled people performed accurate and strong shooting motions directly toward the target direction with stable postures, no matter how it's left, right, front or back.

• Parasites, Hosts and Diseases
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• 제40권2호
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• pp.75-81
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• 2002

We investigated population densities of mosquitoes infected with sporozoites in three highly epidemic areas of Josan-ri and Jangpa-ri (Paju City) and Dongjung-ri (Yeoncheon County) in Korea. Anopheline mosquitoes were collected front both indoors and outdoors by human baiting collection method during the period of the first week of June to the second week of September 1999. Total 13,296 female mosquitoes were collected and 8,650 (65.1%) were Anophelines. Thirty seven percent (3,199) of the Anopheline mosquitoes were captured outdoors and 63.9% (5,531) indoors. Employing a sandwich enzyme-linked immunosorbent assay (ELISA), we analyzed a total of 7,820 Anopheline mosquitoes and found that 7 Anopheline mosquitoes were infected with sporozoites. The positive rate in Josan-ri was 0.14% (5/3,500) and 0.15% (2/1,370) in Jangpa-ri. The total positive rate in all three surveyed areas was 0.09% (7/7,820). The mosquitoes infected with the sporozoites were detected on June $28^{th}$ (n=2), July $5^{th}$ (n=1), July $19^{th}$ (n=1), August $9^{th}$ (n=1), September $6^{th}$ (n=1), and the last one on September $13^{th}$ (n=1). They were all classified as Anopheles sinensis, which showed positive reaction in ELISA test. Therefore it might be concluded that Anopheles sinensis plays an important role in re-emerging malaria transmission in Korea.

• 한국항공우주학회지
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• 제30권6호
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• pp.61-68
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• 2002

초음속 유동장 내 수소 연료의 이중 분사가 갖는 연소 특성에 대한 수치연구를 수행하였다. 연료 이중 분사 유동 구조를 수치적으로 모사하기 비평형 화학반응을 포함한 3차원 Navier-Stokes 방정식과 k-$\omega$ SST난류 모델을 사용하였다. 이중 분사기 사이의 변화에 따른 연소특성의 변화를 이해하기 위해서 파라메터 연구를 수행하였다. 이중 수직분사의 연소특성은 단일 수직분사의 연소특성과 상당히 다른 양상을 보이는 것으로 나타났다. 이중 분사에서 두 분사유동의 연소특성은 서로 다른 것으로 나타났는데, 후방 분사류의 연소 특성은 전방 분사류의 유동 및 연소특성에 크게 영향을 받는 것으로 밝혀졌다. 분사기 사이의 거리가 어떤 특정 거리가 되기 전까지 증가할수록 연소율이 증가하는 것으로 나타났다. 하지만, 그 이후에는 연소율의 증가가 관찰되지 않았으며 오히려 정체압력의 감소가 커져서 전체적인 연소특성은 악화되는 것으로 나타났다. 이는 최적의 연소특성을 위한 두 분사기 사이의 거리가 존재함을 의미하는 것으로 판단된다.

• 한국추진공학회지
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• 제18권4호
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• pp.43-49
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• 2014

국소적 정상초음파장의 교란이 관내 메탄/공기 예혼합화염의 전파속도 및 화염구조에 미치는 영향을 규명하기 위한 실험적 연구를 수행하였다. 슐리렌가시화기법을 이용하여 정상초음파 유무에 따른 화염선단 발달과정의 변이를 상세히 관찰하였다. 정상초음파가 개재할 때, 기연부에서 가로방향의 줄무늬가 생성되었고, 연소반응의 촉진으로 화염의 속도는 증가하였으며, 화염의 발달과정이 부력의 영향으로부터 자유로워져 화염선단의 상하 대칭성을 유지하려는 경향을 보인다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.80-86
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• 2011

Solar reforming of methane with CO2 was successfully tested with a direct irradiated absorber on a parabolic dish capable of 5kWth solar power. And the new type of double-layer absorber - the front layer, porous metal foam which absorbs the radiation and transfers the heat from material to gas, and the back layer, catalytically-activated metal foam - was prepared, and its activity was tested by using electric furnace. Ni was applied as the active metal on the gamma-Al2O3 coated Ni metal foam for the preparation of the catalytically-activated metal foam layer. Compared to conventional direct irradiation of the catalytically activated metal foam absorber, this new type of double layer absorber is found to exhibit a superior reaction and thermal storage performance at the fluctuating incident solar radiation. In addition, unlike direct irradiation of the foam absorber, double layer absorber has better thermal resistance, which prevents the emergence of cracks caused by mechanical or thermal shock. The total solar power absorbed reached up to 3.25kW and the maximum CH4 conversion was almost 59%.

• 한국운동역학회지
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• 제16권2호
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• pp.121-134
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• 2006

The purpose of this study was to analyze the effect of different types of rehabilitation training program on the kinetic and kinematic parameters during sit-to-stand movement(STS) in chronic stroke patients. Two groups of hemiparetic patients, experimental and control, participated in the study. The experimental group participated in a 10-week training program (three sessions/wk, $1{\sim}1.5\;hr/session$) consisting of a warm-up, aerobic exercises, lower extremity strengthening. and a cool-down. The control group participated in an aerobic exercise. Three dimensional kinematic analysis and force platform; were used to analyze the duration of STS, lower extremity angle, and weight bearing ability. The experimental group which had more strength of lower extremity displayed decrease in duration of STS. However, the control group showed increases in duration during sit-to-stand movement. The control group flexed their trunk more than the group did Therefore, it took more time to extend their trunk during STS. The duration in sit-to-stand was affected by the strength of lower extremity and the angle of trunk movement. The angles of ankle and knee joint had an influenced on duration of STS. The post experimental group performed with their feet near the front leg of the chair during sit-to-stand, therefore the duration was decreased. The repetitive sit-to-stand movements as a resistance exercise was effective to hemiparetic patients in learning mechanism of sit-to-stand. The control group showed decreased differences in the vertical ground reaction forces between paretic and non-paretic limbs. Their training program included strengthening exercise that may help improving weight bearing ability. The control group showed increases in the center of pressure in the anteroposterior and mediolateral displacement. This means that the stability of movement was low in the control group. Their training program which combined aerobic and strengthening exercises that are more effective to improve the stability of movement.