로봇 팔의 제어를 위한 포텐셜미터를 이용한 팔 움직임 감지 시스템 개발

박기훈,박성훈,윤태성,곽군평,안호균,박승규,Park, Ki-Hoon,Park, Seong-Hun,Yoon, Tae-Sung,Kwak, Gun-Pyong,Ann, Ho-Kyun,Park, Seung-Kyu 한국정보통신학회 2012 한국정보통신학회논문지 Vol.16 No.4

본 논문은 사람 팔의 움직임 감지 시스템을 제안한다. 기존의 모션측정 장비들은 고가이거나 혹은 특수한 장소가 따로 필요하였다. 또한 측정한 데이터들을 필요한 데이터로 변환하는 추가적인 시간도 필요하였다. 본 논문에서는 사람이 입을 수 있으며 가격이 매우 저렴하고 추가적인 데이터 변환이 필요 없는 시스템을 개발 하였다. In this paper, an arm motion sensing system using potentiometer is developed. Most motion sensing systems use optical method for the quality of motion data. The optical method needs much cost for manufacturing capture system and takes much time for correcting the captured data. And mechanical method entails relativity low cost, but it uses the wires and takes much time for correcting the data like the optical method. For solving the problems, in this paper, an arm motion sensing system is newly developed using low cost potentiometer and based on the suggested simple calculation method for the joint angles and the angular velocities. For the verification of the performance of the developed system, practical experiments were executed using real human arm motion and a robot arm. The experimental results showed that the motion of the robot arm controlled by the output of the developed motion sensing system is much similar with the motion of human arm.

상용화제의 첨가에 따른 재생 폴리프로필렌/폐타이어 분말 복합체의 기계적 특성 분석

박기훈,김동학,정종기,김성길,방대석,오명훈,김봉석,Park, Ki-Hun,Kim, Dong-Hak,Jung, Jong-Ki,Kim, Seong-Gil,Bang, Daesuk,Oh, Myung-Hoon,Kim, Bong-Suk 한국자원리싸이클링학회 2014 資源 리싸이클링 Vol.23 No.1

In this study, waste polypropylene and waste ground rubber tire(WGRT) composites were prepared by using a modular intermeshing co-rotating twin screw extruder. The effect of three main factors such as WGRT contents, particle size, compatibilizers on the properties of waste PP/WGRT composites was extensively investigated. Tensile strength of the composites was decreased with an increase in WGRT contents, whereas elongation at break and impact strength were increased. The tensile strength, elongation at break and impact strength of the composites with the smaller size of the WGRT were more enhanced. Addition of PP-g-MA into waste PP/WGRT composites exhibited better tensile strength. However, elongation at break and impact strength were slightly decreased with increasing of PP-g-MA. On the other hand, tensile strength, impact strength and elongation at break of the composites were increased by adding the EPDM-g-MA and SEBS-g-MA. Especially, elongation at break was significantly increased compared to the composite with PP-g-MA. 본 연구에서는 이축 스크류식 치합형 압출기를 이용하여 재생 폴리프로필렌/폐타이어 분말 복합체를 제조하였다. 세 가지 주요 실험 변수 즉 폐타이어 분말 함량, 폐타이어 분말 크기, 상용화제의 종류 및 함량이 재생 폴리프로필렌/폐타이어 분말 복합체의 물성에 미치는 영향을 자세히 관찰하였다. 폐타이어 분말의 함량이 증가 할수록 인장강도는 감소하였으며 신장률과 충격강도는 증가하는 것이 관찰되었다. 또한 폐타이어 분말의 크기가 작아질수록 인장강도 및 신장률, 충격강도는 증가하였다. PP-g-MA를 첨가 하였을 시 복합체의 인장강도는 증가하였지만 신장률과 충격강도는 감소하였다. 반면에, 상용화제 EPDM-g-MA, SEBS-g-MA의 경우에는 복합체의 인장강도, 충격강도가 증가하였고 신장률은 PP-g-MA와 비교했을 때 매우 큰 폭으로 증가하는 것이 관찰되었다.

펄스 반복률에 의한 반도체 소자의 오동작 모드와 고장률에 관한 연구

박기훈,방정주,김륙완,허창수,Park, Ki-Hoon,Bang, Jeong-Ju,Kim, Ruck-Woan,Huh, Chang-Su 한국전기전자재료학회 2015 전기전자재료학회논문지 Vol.28 No.6

Electronic systems based on solid state devices have changed to be more complicated and miniaturized as the electronic systems developed. If the electronic systems are exposed to HPEM (high power electromagnetics), the systems will be destroyed by the coupling effects of electromagnetic waves. Because the HPEM has fast rise time and high voltage of the pulse, the semiconductors are vulnerable to external stress factor such as the coupled electromagnetic pulse. Therefore, we will discuss about malfunction behavior and DFR (destruction failure rate) of the semiconductor caused by amplitude and repetition rate of the pulse. For this experiment, the pulses were injected into the pins of general purpose IC due to the fact that pulse injection test enables the phenomenon after the HPEM is coupled to power cables. These pulses were produced by pulse generator and their characteristics are 2.1 [ns] of pulse width, 1.1 [ns] of pulse rise time and 30, 60, 120 [Hz] of pulse repetition rate. The injected pulses have changed frequency, period and duty ratio of output generated by Timer IC. Also, as the pulse repetition rate increases the breakdown threshold point of the timer IC was reduced.

곡면형 압전 복합재료 작동기 LIPCA 개발

박기훈(Ki Hoon Park),윤광준(Kwang Joon Yoon),박훈철(Hoon Cheol Park) 한국항공우주학회 2002 韓國航空宇宙學會誌 Vol.30 No.5

조사료용 다수성 총체밀 품종 ‘청우’

김경훈(Kyeong-Hoon Kim),서재환(Jae-Hwan Seo),박태일(Tae-Il Park),한옥규(Ouk-Kyu Han),박기훈(Ki-Hun Park),송태화(Tae-Hwa Song),박종철(Jong-Chul Park),박철수(Chul-Soo Park),강천식(Chon-Sik Kang),박형호(Hyoung-Ho Park),박남건(Nam-Gun Pa 한국육종학회 2015 한국육종학회지 Vol.47 No.3

“Cheongwoo”, a white winter wheat (Triticum aestivum L.) cultivar was developed by the National Institute of Crop Science, RDA. It was derived from the cross“Kanto75/8/Tapdong/4/Bb#1/Jangkwang//STRAMCHO/3/Suwon220/5/Suwon185/ CI12703//Kanto75///Suwon219/7/F1277” and “Keumkang” in 1998 at RDA. “Keumkang” is a semi-hard white winter wheat with high yield. And mother plant is a winter wheat with long culm length, high yield. “Cheongwoo” was evaluated as “Iksan326” in Advanced Yield Trial Test in 2007. It was tested in the regional yield trial test between 2008 and 2009. “Cheongwoo” is first whole crop wheat with long culm length, high-yield. The Heading date of “Cheongwoo” was similar to “Keumkang”. The average forage yield of “Cheongwoo” was about 14.8 ton ha-1 in dry matter in paddy field. This dry matter was higher than dry matter of “Keumkang” (13.2 ton ha-1). The cultivar had 97 cm of culm length, 1,070 spikes per m2 and it showed better rate of culm. Culm length of “Cheongwoo” were longer than “Keumkang”. This cultivar would be suitable for the area above the daily minimum temperature of -10°C in January in Korean peninsula. Our research will improve good-quality of silage by using winter cereal crops.

Krackow 봉합술을 이용한 아킬레스 건 급성 파열의 치료

김형년,박기훈,박용욱,Kim, Hyong-Nyun,Park, Ki-Hoon,Park, Yong-Wook 대한족부족관절학회 2009 대한족부족관절학회지 Vol.13 No.1

Purpose: We try to evaluate the clinical results of the acute Achilles tendon rupture treated with Krackow suture technique. Materials and Methods: We reviewed 27 patients with acute Achilles tendon rupture treated between October 2005 and September 2007. There were 26 complete ruptures and 1 incomplete rupture. All were ruptured at tendinous area. There were 21 men and 6 women, and mean age was 38 years. We repaired ruptured Achilles tendon with Krackow suture technique. The results were evaluated with Arner-Lindholm scale for patients' satisfaction, strength of calf muscle power, calf circumference, and ankle motion. The average follow-up was 29 months. Results: The patients' subjective clinical results was excellent in 25 cases and good in 2 cases. There were 15 cases of less than 1 cm, 6 cases of 1${\sim}$3 cm, and 1 case of more than 3 cm in the calf circumference difference between the normal and affected leg. There were 20 cases of less than 5 degrees, and 2 cases of more 5 degrees in the difference of range of motion between the normal and affected ankle. We had an experience of postoperative deep infection in one diabetic patient. Conclusion: We had a good clinical result for acute Achilles tendon rupture treated with Krackow suture method. So we recommand Krackow suture technique for acute Achilles tendon rupture.

Antitumor Sterol Isolated from the Fruiting Body of Pleurotus eryngii

이영훈,박기훈,이병원,조용운,최영주,갈상완,Lee Young-Hoon,Park Ki-Hun,Lee Byong-Won,Cho Yong-Un,Choi Young-Ju,Gal Sang-Wan Korean Society of Life Science 2006 생명과학회지 Vol.16 No.2

새송이버섯으로부터 활성추적법으로 항암활성이 있는 물질인 에르고스테롤 프록사이드를 분리하였다. 이 스테롤의 구조는 분광법과 NMR법으로 확인하였으며 분자식은 $C_{28}H_{44}O_3$이었다. 폐암과 난소암에 $IC_{50}$값은 각각 $7{\mu}M$과 $14{\mu}M$이었다. DNA단편화 실험에서 이 화합물은 암세포의 chromosimal DNA 를 사닥다리모양으로 분해하였고, 세포 분열주기의 억제실험에서 G1단계를 억제함을 관찰하였다. Activity-guided fractionations led to the isolation of antitumor compound, ergosterol peroxide ($5{\alpha},\;8{\alpha}-epideoxy-24(R)-methylcholesta-6,\;22-dien-3{\beta}-ol$) from the fruiting body of Pleuratus eryngii that was cultivated artificially. This sterol structure was established by using spectroscopic methods ($^1H\;and\;^{13}C$ nuclear magnetic resonance and high resolution mass spectra). The purified compound showed a molecular formular of $C_{28}H_{44}O_3$ displaying characteristic features of epidioxy sterols. The 50% inhibitory concentrations ($IC_{50}$) of ergosterol peroxide against human lung cancer cell line (A549) and human ovarian cell line (SK-OV3) were $7{\mu}M\;and\;14{\mu}M$, respectively. In the DNA fragmentation assay, the compound showed the programmed cell death causing the chromosomal DNA fragmentation. It reveals that ergosterol peroxide arrests G1 phase of the cell division cycle.

릴레이 접점 열화에 따른 바운싱 현상 분석

류재만,최순호,박기훈,허창수,Ryu, Jae-Man,Choi, Sun-Ho,Park, Ki-Hoon,Huh, Chang-Su 한국전기전자재료학회 2014 전기전자재료학회논문지 Vol.27 No.6

The relay used is gradually increased. Because it is possible to easily control the high voltage and current. Bounce phenomenon is generated in contact during operation relay. As the result, arc is generated at the contact, thereby shortening the contact lifetime. In this study, we analyzed the bouncing phenomenon due to deterioration. It can be seen from the experimental results, and it is minimized at about 100,000 times. Bouncing phenomenon to increase again after the minimization. Consequently, the bouncing related to contact weight and shape of contact surface.

탄소나노튜브와 스테인레스강 단섬유를 함유한 폴리프로필렌 복합체의전기저항 및 기계적 특성

정종기(Jong Ki Jung),박기훈(Ki Hun Park),방대석(Dae Suk Bang),오명훈(Myung Hoon Oh),김봉석(Bong Seok Kim),이종근(Jong Keun Lee) 한국고분자학회 2014 폴리머 Vol.38 No.2

본 연구에서는 이축 스크류식 압출기를 이용하여 폴리프로필렌(PP)에 도전성 필러인 다중벽 탄소나노튜브(MWNT)와 스테인레스강 단섬유(SSF)를 첨가하여 복합체를 제조하였으며, 이에 대한 표면저항 및 기계적 특성을조사하였다. 표면저항을 측정한 결과 PP/MWNT에 소량의 SSF를 첨가하였을 때 더 낮은 MWNT 함량에서percolation threshold가 나타났다. 그리고 제조된 복합체에 대한 인장시험 결과 순수 PP와 비교해서 파괴점 신장률은 감소하였으나 탄성률과 강도는 증가하였다. 또한 동역학분석을 통하여 MWNT와 SSF 복합체의 저장탄성률과tan δ에 미치는 영향을 조사하였으며, SEM을 이용하여 필러들의 모폴로지 및 복합체의 파단면을 관찰하였다. Polypropylene (PP) composites containing conductive multi-walled carbon nanotube (MWNT) and stainless steel short fiber (SSF) were manufactured using a twin screw extruder and characterized their surface resistivity and mechanical properties in this work. Surface resistivity measurements showed that the percolation threshold appeared at a lower MWNT loading when a small amount of SSF was added to PP/MWNT composites. Tensile modulus and strength of the composites increased but elongation-at-break decreased greatly compared to pure PP. Also, the effects of MWNT and SSF on storage modulus and tan δ from dynamic mechanical analysis for the composites were examined, and the morphologies of fractured surface and the fillers were observed using a scanning electron microscope.

포도와 오이즙액을 이용한 동충하초(Paecilomyces japonica) 균사체 배양액의 피부 주름개선효과

이영훈,최우식,박기훈,최영주,갈상완,Lee Young-Hoon,Choi U-Sic,Park Ki-Hoon,Choi Young-Ju,Gal Sang-Wan 한국생명과학회 2006 생명과학회지 Vol.16 No.3

포도와 오이즙액에 동충하초 균사체 배양액을 화장품으로서의 이용가능성을 조사하였다. 콜라겐 생성촉진 효과에서는 사람의 섬유아세포에서 시험물질 $0.1{\sim}0.5%$ 농도에서 콜라겐 생합성을 증가시키는 것을 관찰하여 동충하초 균사체 배양액은 적절한 농도에서 세포내 콜라겐 생성을 증가시키는 것으로 판단하였다. 포도와 오이즙액에 동충하초 균사체 배양액의 항산화효과에서는 항산화제인 Vit. C와 함께 SOD 활성능을 측정한 결과 동충하초 균사체 배양액이 0.01% 부터 1.0% 범위에서 농도의존적으로 SOD 활성을 증가시켜 0.1% 에서는 약 50% 정도 1.0% 에서는 90% 정도의 슈퍼옥사이드 라디칼을 소거시키는 것으로 나타났다. 항 혈액응고제로 알려진 퀘르세틴의 함량증가에서는 최초 포도와 오이즙액보다 배양 후의 농도가 약 15배 이상 증가하여 피부의 항 혈액응고에도 효과가 있을 것으로 판단되며, 이를 인체에 대한 자극시험을 실시한 결과 30명의 피검자 모두에게서 피부자극이 전혀 일어나지 않음을 확인하여 인체에 무해한 것으로 판단되었다. 따라서 포도와 오이즙액에 동충하초 균사체 배양액은 피부에 대한 부작용이 전혀 없으며 주름개선효과 및 항산화 활성을 갖는 기능성 화장재료로서의 이용 가치가 매우 높을 것으로 사료된다. The possibility of usage as cosmetic resource of the mycelial culture broth of P. japonica in the mixture of cucumber and grape extracts was investigated. In the effect of collagen synthesis promotion in human fibroblast cells, the culture broth of P. japonica of 0.1, 0.5 and 1.0% concentration increased the amount of collagen synthesis than that of control cells. The culture broth increased the SOD activity in the concentration dependant manner of 0.01% to 1.0% in the antioxydation activity test. About 90% of superoxide radical was eliminated by 0.5% concentration of the culture supernatant in the antioxydation test. Anticoagulant quercetin in the course of mycelial growth in the mixture of cucumber and grape extract was accumulated to 15 folds than that of pre-culture. In the skin safety test of the culture broth, there is no any skin damage signal in the tested 30 people. Taken together, we concluded that the culture broth of P. japonica in the mixture of grape and cucumber extracts can be used as a cosmetic resource.