步速變化에 따른 미끄러짐의 생체역학적 연구

서국웅,윤양진,서국은,이중숙,김용재,이언석,이훈식 釜山大學校 附設 體育科學硏究所 1992 體育科學硏究所 論文集 Vol.8 No.-

The purpose of this study was to analyze walking steps to prevent unnecessary energy consuming and prevention of injury from sliding when someone was walking. The questionnaire, high speed video system, E.M.G. system, and force platform system were used to analyze sliding mechanism in biomechanical perspective. Several results were found as following: 1. According to questionnaire regarding sliding, 93.3% of participants have sliding experiences. People have sliding experiences by greasy floor(48.4%) and obstacle (22.5%). Sliding types were found from different kinds of shoes such as sneakers (48.8%) and boots (34.2%). The results were presented as following 44.6% of participants were fall down front direction and 40.3% of people fell down rear side. 2. According to the high speed video system analyzer, step sliding increased with increasing step speed from distance and acceleration speed experiment with 80 steps/min, 100 steps/min, 120 steps/min. Also, the most sliding were occurred with sneakers, boots, and bare feet as order. 3. According to E.M.G. test results, the vastus lateralis M., the vastus medialis m., and the tibialis anterior m. of electric action potential presented strongly when participants fell front, rear, and right side. The vastus lateralis m. and the tibialis anterior m. of electric action potential presented strongly when someone fell left side, but the vastus medialis m. and the gastrocnemius m. of electirc action potential presented as weaker. 4. According to the force platform test results, the most big change of floor antipower of x-axis presented when someone fell the left side. The most of big change of floor antipower of y-axis presented when someone fell down rear side. The most of big change of floor antipower of z-axis presented similarly when someone fell the front, rear, left, and right side.

Biochemical Characteristics and Antimicrobials Susceptibility of Salmonella gallinarum Isolated in Korea

Ki-seuk Kim,Young-ju Lee,Yong-kuk Kwon,Ryun-bin Tak 대한수의학회 2003 Journal of Veterinary Science Vol.4 No.2

Characteristics and Antimicrobials Susceptibility of Salmonella gallinarum Isolated in KoreaYoung-ju Lee, Ki-seuk Kim1,*, Yong-kuk Kwon and Ryun-bin Tak1Avian Disease Division, National Veterinary Research and Quarantine Service, Anyang 430-824, Korea1College of Veterinary Medicine, Kyungpook National University, Daegu 702-701, KoreaReceived February 13, 2003 / Accepted April 30, 2003J. Vet. Sci. (2003), 4(2), 161-166JOURNAL OFVeterinaryScience*Corresponding author: Ki-seuk Kim College of Veterinary Medicine, Kyungpook National University, Daegu 702-701, Korea Tel: 82-53-950-5962, Fax: 82-53-950-5955 E-mail: kimkiseuk@knu.ac.kr

Study on Microstructure and Mechanical Properties of the Al–25Cr–5Si (at%) Alloy Powder Using Gas-Atomization and SPS Process

Yong‑Ho Kim,Hyo‑Sang Yoo,Jeong‑Han Lee,Ik‑Hyun Oh,Hyun‑Kuk Park,Hyeon‑Taek Son 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.7

In order to investigate the microstructure and mechanical properties on Al–25Cr–5Si (at%) alloy, a mixed powder with pureelements and an alloy powder using a gas atomization process were used. Fine and high purity Al–25Cr–5Si (at%) alloypowder was successfully prepared by gas atomization and densified using a spark plasma sintering (SPS) process. The overallpowder size distribution of the mixed Al, Cr, and Si elemental powders was in the range of 10–15 μm. The atomized Al–Cr–Sialloy powder was fine and spherical in morphology and difficult to be formed by intermetallic formation. Densification wasclearly confirmed at 1000 °C, with almost isolated pores formed, by clear removal of pores between particles, deformationof particles, an increase in the number of contacts, and a change in size between particles. As a result of XRD analysis ofthe sintered compacts, single phase was observed using the mixed powder, but the compact using gas atomization remainedthe alloy phase even at the process temperature. The Vickers hardness of the compacts by mixed powder was observed at59.70 Hv and the compact using gas atomized powders on the temperature 1000 °C of the Vickers hardness increased to702.6 Hv. The compressive yield strength of the compact with mixed powder was 195.24 MPa and the compressive strengthof the compact with gas atomized powder increased to 802.07 MPa. It is considered not to be decomposed by the AlCrSi,Al13Cr4Si4and Al8Cr5phases sintering process, resulting from the improvement of mechanical properties.

칼라센서를 이용한 도정도 측정장치 개발

이용국,이대원,윤두현,이재현 성균관대학교 생명과학자원연구소 1996 生命資源科學硏究 Vol.3 No.2

A whiteness measurement system was designed and constructed using the color sensor. The results of its performance were compared with commercial product (Japan, Kett Co.). A degree of rice milling grading is very closely related to the rice color. Measuring and evaluating the small amount of the reflectance depend on the system including color sensor, light source, detector sensitivity, and its geometric shapes. The main components of prototype included lamps as a light source, Amorphous full color sensor with three filters, D. C. power supply, amplifier, A/D converter, and compatible PC computer. Based on the results of this research the following conclusions were made: [1] It was considered suitable that the amorphous full color in the system was used in rice milling degree measurement. [2] The results of comparison between prototype and the Kett whiteness meter were showed that correlation coefficient of prototype was 0.9687 and that of the commercial whiteness meter was 0.9954.

3중 적층형 압전 트랜스듀서의 주파수 특성

李鎔國,李海龍,韓得永 건국대학교 1995 學術誌 Vol.39 No.2

Frequency characteristics of a three-layered piezoelectric transducer are analyzed with three piezoelectric ceramic disk vibrators and two sheets of thin isolator. The electric input voltage near its fundamental resonant frequency is applied to the center vibrator and the output voltages across the left and the right vibrators are connected in parallel or in series to the resister load. Moreover, equivalent circuits are derived from the Mason's model for parallel connection and series connection. Also, equations of voltage ratio, resonant frequency, phase angle between the Input and output voltages, and bandwidth have been derived. Computed values from those equations are compared with measured values. Both are shown to agree well each other. Key words : Three-layered piezoelectric transducer(3중 적층형 압전 트랜스듀서), Equivalent circuit(등가회로), Parallel connection(병렬연결), Series connection(직렬연결), Resonant frequency(공진주파수), Bandwidth(대역폭)

오이 특징점 인식을 위한 영상처리 알고리즘 개발

이원희,이대원,이용국 성균관대학교 생명과학자원연구소 1997 生命資源科學硏究 Vol.4 No.1

An image processing algorithm was designed and constructed to recognize and measure the geometric shapes of a cucumber for a short real time using a computer vision system. The main components of the vision system included fluorescent lighting equipment as a light source, CCD (charge coupled device) camera, VGA (video graphics array), PC computer to grade a stationary cucumber. The algorithm was developed to recognize geometric features of a cucumber and also to reduce the processing time of them. Total image processing time was about 0.5 second, where only grabbing time was required more than 0.3 second. Geometric features include straight length, chord length, bending length, area, bending angle, maximum thickness and minimum thickness. Qualitative performance of the algorithm proved to be a reliable algorithm for geometric features of a cucumber.

벼 재배기간중 전남동부지역 농촌하천의 수질과 분포초종

이도진,조주식,국용인,안호근 한국환경농학회 2003 한국환경농학회지 Vol.22 No.1

전남 동부권에 위치하는 농경지 주변 4개 하천에 대하여 벼 재배기간을 전후한 시기에 하천수질의 특성과 분포하는 초종을 조사한 결과는 다음과 같다. 하천수질 특성은 다양하였으며 조사기간중 각 하천수의 pH는 6.5~8.3 범위였고, EC는 벌교천(162~4,910 μS/cm)에서 가장 높았으며 보성천(114.7~286.6 μS/cm), 송광천(74.8~147.4 μS/cm), 이사천(61.6~82.1 μS/cm)순이었다. 조사기간중 총질소 함량은 보성천(1.9~7.4 mg/L), 벌교천(2.1~3.9 mg/L), 송광천(2.4~3.4 mg/L), 이사천(1.7~2.6 mg/L)순으로 호소수질 환경기준 1등급(0.2 mg/L)과 농업용수 수질기준(1 mg/L)을 모두 초과하였다. 그 밖의 대부분 조사항목(K, Ca, Mg, Na, Cl^- 등)은 하천에 따른 함유량 고저 차이는 있었으나 모내기를 전후한 시기에 영양염류 함량이 가장 높게 나타나 보성천에서는 5월, 송광천과 이사천에서는 6월이었다. 4개 하천의 조사지점에서 관찰된 초종수는 모두 16과 30종이었으며 송광천, 보성천, 이사천, 벌교천에서 각각 18종, 19종, 15종 및 5종으로서 다년생은 17종, 일년생과 2년생은 13종이 출현하였다. 침수성 초종은 검정말, 말즘, 물수세미, 부유성 초종은 개구리밥과 좀개구리밥, 추수성 초종은 갈대, 고마리, 미나리, 여뀌, 줄 등이 관찰되었다. 물가와 주변에서는 개구리자리, 개피, 달뿌리풀, 돌소리쟁이, 물억새, 미국가막사리, 바늘골, 방동바니대가리, 뱀딸기, 사마귀풀, 삿갓사초, 살갈퀴, 선피막이, 소리쟁이, 쇠방동사니, 여뀌바늘, 큰도꼬마리, 토끼풀, 환삼덩쿨, 황새냉이 등의 20종이 관찰되었으며 그 중 고마리, 소리쟁이, 환삼덩쿨은 하천의 모든 조사지점에 출현하였다. The characteristic of the quality of stream water and the nlparlan vegetation during rice cultivation in the rural area of the eastern Jeonnam province was surveyed from April to November, 2000. The water quality of the streams during rice cultivation was variable. The pH of these water bodies ranged from 6.5~83. Electro conductivity (EC) at each water body ranged from 162~4,910 μS/cm for Beolgyo-cheon, 114.7~286.6 μS/cm for Boseong-cheon, 74.8~147 μS/cm for heon, and 61.6~82.1 μS/cm for Isa-cheon. Total nitrogen and other parameters (K, Ca, Mg, Na, CT, SS) were higher at May (Boseong-cheon) through June (Songgwang-cheon, Isa-cheon) during the transplanting season than these same parameters at August, October and November. Thirty weed species of sixteen families were found in the survey areas of Songgwang-cheon, Boseong-cheon, Isa-cheon and Beolgyo-cheon. Nine annual weeds, four biennial weeds, and seventeen perennial weeds were found, several different life forms were identified. Of those species three were submerged, two were free floating, five were emerged, and twenty were water-side weeds.

로봇 포도수확기를 위한 엔드이펙터 개발

이대원,김현태,이용국 성균관대학교 생명공학연구소 2001 生命工學硏究 Vol.7 No.1

Most of fruits need laboring greatly to harvest fruit in the period of harvest season. Grape also needs requiring a lot of labor to harvest in time, since harvesting of grape is cut and graped by hand. At abroad, especially, a harvester of grape, which is not eat freshly raw grape fruit but is processed to be made wine, was developed in France. However, a harvester of grape which can eat freshly raw grape fruit haven't not been developed. Therefore, this study was designed and constructed to develope an end effector of the robotic harvesting system. In order to find average and standard deviation of size and shape of a bunch grape, the grape farm was visited and investigated to find out the important factors for end effector to be designed and built. The efficient end-effecter should reach very well a bunch of grape without touching obstacles, such as leaf and stem in the grape vine. Also, it was made as simple, small and light as possible. Therefore, It was made of duralumin, which was lighter material than iron, to reach easily fresh grape fruit and reduce a torque. After finding the optimum initial speed, slew speed, ramp speed, the end effector proved to be a smooth operating end effector. For verifying efficiency of the end-effecter, the control board was designed and manufactured, and also developed the software to control the motors of the end effector.

21C 부산체육의 활성화를 위한 시설 및 프로그램 연구

이상봉,김용재,서국웅,양점홍 釜山大學校 附設 體育科學硏究所 1996 體育科學硏究所 論文集 Vol.12 No.-

This research investigated Institution and Program for the Development of the Pusan Sports in 21C by examining literatures. Conclusiona from the results as follows. 1. We should provide a long period propulsion project in three stage with planning, diffusion and development stage for the bring development and diffusion of Program. 2. We should establish a specialty research institution, the exclusive responsibility of program's development and research. 3. We should provide various participation programs not that for an elite athlete but that for all nation. 4. Enlarge the same taste club and we must support with various administration and financial. 5. Cultivate a specialty leader and we must take interested in the study and training with continual.

코크스 오븐에서 에너지 효율 향상을 위한 통합연소진단시스템 개발

이지수,이용국,이성우,심재우 한국공업화학회 2004 응용화학 Vol.8 No.1

In making coke through carbonization process, it is possible to produce the required high quality coke in blast furnace and reduce the cost of energy as well as increase the life of coke oven if we maintain the desired coke oven temperature by means of optimal combustion management (CM). In this study, hybrid combustion diagnostic expert system (HCDES) was developed through analyzing the trend and temperature distribution of flues in the oven and combining the domain expert's knowledge. The model also considered and incorporated the characteristics and the structure of the oven. In developing the diagnostic system, a general and accessible expert language, CLIPS (C Language Integrated Production System) was used.