시각정보를 이용한 선상물체모서리의 3차원 위치계측

이한식 충북대학교 산업과학기술연구소 1987 산업과학기술연구 논문집 Vol.1 No.1

In the paper, we describe the principle, the procedure and calculation of the measurement. Finally the experimental results are shown and discussions are given. A vertically mounted camera and a horizontal table ire used for the experiment, and the position errors for fine wires is less than 0.8 percent of the site of sight.

임계사고율법을 활용한 위험 가로구간 설정 (청주시를 사례로)

박병호 ( Byung Ho Park ) 충북대학교 산업과학기술연구소 2011 산업과학기술연구 논문집 Vol.25 No.2

This study deals with the geometric and traffic accident of road section. The purpose of the research is to analyze the hazardous road section using critical accident rate method and to clarify the reasons why they are dangerous. The main results analysed are as follows. First, results of determination of the hazardous road section using critical accident rate method, 177sectors of the total 496sectors was set at the hazardous road. Second, divided into the three stages degree of risk, low hazardous roads were 43sectors, medium hazardous roads were 57sectors, and high hazardous roads were 59sectors. Third, the hazardous roads are not differ between regular roads results from the test that hypothesis, hazardous roads has crossing number, enter the number, street lamps, and many entrances, also right turn and left turn lane are relatively longer length. finally, by the hazardous degree statistical analysis results, longer median strip length, fewer 굴곡점 수 high hazardous roads section.

첨가제를 함유한 미세물분무 소화시스템의 유류화재 소화특성

신창섭 ( Chang Sub Shin ),황석근 ( Suk Keun Hwang ) 충북대학교 산업과학기술연구소 2011 산업과학기술연구 논문집 Vol.25 No.2

Fire suppression system using fine water mist have been studied as substitution of Halon system because it is eco-friendly fire suppression agent. And also fine water system can be applied to local fire extinguishing system and has excellent extinguishing performance.In this study, the changes in physical properties of solution that restrains sodium carbonate were measured. And extinguishing experiment was carried out using n-Heptane pool fire in chamber, and the flame temperature and extinguishing characteristics of water mist containing sodium carbonate were measured.As a result, sodium carbonate was more effective at low pressure suppression system than high pressure system, and has enough freezing temperature.

도시부/지방부 회전교차로 사고모형

박병호 ( Byung Ho Park ),임진강 ( Jin Kang Lim ) 충북대학교 산업과학기술연구소 2011 산업과학기술연구 논문집 Vol.25 No.2

This study deals with the accident models of roundabout. The goals of the study are to analyze the characteristics of accidents by area and to develop the accident models. In pursuing the above, this study gives particular attentions to collecting the data of geometric structures and accidents of 39 roundabouts. The accident data are the 3-year data collected from Korea Road Traffic Authority(KoROAD). Using SPSS 17.0, the multiple linear regression models are developed. The main results are as follows. First, the accident model of urban roundabout which was statistically significant was developed. The independent variables were analyzed to be the ADT, average number of entry lane, average number of splitter islands and parking lot presence. Second, the accident model of rural roundabout which was statistically significant was developed. The independent variables were analyzed to be the ADT, ratio of HOV and average width of entry lane.

대직경 고장력볼트 마찰이음의 효율성 연구

김태철 ( Tae Choul Kim ),양건봉 ( Keun Bong Yang ),김경남 ( Kyoung Nam Kim ),정경섭 ( Kyoung Sup Jung ) 충북대학교 산업과학기술연구소 2011 산업과학기술연구 논문집 Vol.25 No.2

Many steel structures have been constructed with high-strength steels and ultra-thick steel plates in accordance with the development of steel materials. Steel structures such as steel bridges have to be connected with bolts or welding. The bolted joints are more frequently used in the field due to easy management. Domestic KS(Korea Standards) reads that bolted connection must be at least 75% of strength of member; however, it seems to be very conservative. This study aims to examine appropriateness of the conservative KS(Korea Standards) by analyzing formation of bridge under construction. Furthermore, more economic and efficient way without degrading any strength of bolted connections was suggested here.

셀프 피어싱 리벳의 형상 설계를 위한 유한요소해석

조해용 ( Hae Yong Cho ),김동범 ( Dong Bum Kim ),김관우 ( Kwan Woo Kim ) 충북대학교 산업과학기술연구소 2011 산업과학기술연구 논문집 Vol.25 No.1

Self-piercing riveting(SPR) is a sheet joining method that can be used for materials which are difficult or unsuitable to weld, such as aluminum alloy and different steel sheet metals. No pre-drilled hole is needed for SPR; the rivets are pushed directly into the sheets clamped together between a blank holder and a die in a press tool. In this paper, self-piercing rivet and anvil were designed for four joining conditions with dissimilar sheet metals. SPR was simulated by using commercial FEM code DEFORM-2D. In simulation of SPR process, various strengths of self-piercing rivet were considered. The mechanical properties could be determined by tensile test for quenched rivets and sheet metals. The designs of rivet and anvil were modified by comparisons of simulated results.

노즐 이송속도에 따른 전도성 잉크의 패턴성형 특성

이인환 ( In Hwan Lee ),강준희 ( Jun Hee Kang ) 충북대학교 산업과학기술연구소 2011 산업과학기술연구 논문집 Vol.25 No.1

Additive manufacturing (AM) technology is widely used to manufacture prototype, mold and products. There are various AM technologies according to the materials and plastic, metal, ceramic and paper are the major materials. These materials are used alone for each AM technology; hence there are limitations to produce various applications. This is a fundamental research for the multi-material AM technology which composed of stereolithography and direct writing technology. In this research, pattern generation characteristics of the conductive material direct writing is conducted experimentally. From the experimental results, it was found that a smaller nozzle diameter is favorable for a smaller width of the conductive ink rather then faster nozzle speed and/or lower flow rate of the ink. And there are a certain range of nozzle speed and flow rate for a given nozzle speed to fabricate a stable line width fabrication. A sample pattern was fabricated successfully using experimental results.

유한요소법에 의한 Self-Piercing Rivet의 단조 공정설계

조해용 ( Hae Yong Cho ),김동범 ( Dong Bum Kim ),박진용 ( Jin Yong Park ) 충북대학교 산업과학기술연구소 2011 산업과학기술연구 논문집 Vol.25 No.1

Self-piercing rivet is sheet joining method. It is being used more to join aluminum sheets. Self-piercing riveting is a large-deformation process that involves piercing. The self-piercing rivet, under the press from the punch, pierces the top sheet and forms a mechanical interlock with the bottom sheet. In this study, the forging process was designed for manufacturing self-piercing rivet. Forging process has been simulated by using commercial FEM code DEFORM-2D. In simulation of forging process for manufacturing rivet, process sequence, formability, forging load, distributions of stress and strain were investigated. The suitable forging process could be designed by comparisons of simulation results. The developed process consists of four stages: upsetting, first chamfering, back extrusion, second chamfering. The simulated results for forging process were confirmed by experimental trials with the same condition.

스타팅블록을 이용한 반응나이 측정 시스템 개발

주진원 ( Jin Won Joo ),정홍식 ( Hong Sik Chung ) 충북대학교 산업과학기술연구소 2011 산업과학기술연구 논문집 Vol.25 No.2

Recently, Many people has an interest in health and physical age. In this paper, a modified starting block which can be used to prevent fraud from start in training, and at the same time, reaction ages indicators to measure the physical age has been developed. To this end, the load cell mounted on the starting blocks of a program that can handle signals in real time was developed. In addition, to predict the records of 100 m sprint pace, a measuring device and signal processing program was developed. The test results show that measuring error by loadcell and signal processing to actual force is within 0.03% tolerance, which is relativerly small compare to general error of 0.05% in application of loadcell. Enhancement of software and more samples would provide this product to be used usefully in health management to determine physical age.

생체형상을 이용한 관절연골 재생 시스템의 개발

황보태영 ( Taeyoung Hwangbo ),이인환 ( In Hwan Lee ),이승재 ( Seung Jae Lee ) 충북대학교 산업과학기술연구소 2011 산업과학기술연구 논문집 Vol.25 No.2

Recent experimental observations support the hypothesis that mechanical stimuli play a role in regulating specialized molecules expression in articular cartilage in vitro and in vivo. These specific molecules might be induced by the initiation of relative motion between the articular cartilage surfaces. Other studies have demonstrated that the continuous passive motion (CPM) bioreactor for whole joint can provides a platform for possible future in vitro studies and applications including possible interactions of biomechanical and biochemical signals. The objectives of this study were to develop the biomimetic bioreactor could be used to stimulate a whole joint during culture. This system consists of a joint culture chamber and a CPM-like stimulation device. This system could be used to investigate the effects of rehabilitative joint motion in dynamic culture..