고속 HMC 이송계의 운동특성 평가 및 운동오차 예측

최헌종,허남환,강은구,이석우,홍원표 한국공작기계학회 2004 한국공작기계학회 추계학술대회논문집 Vol.2004 No.-

Recently, the evolution in production techniques (e.g. high-speed milling) and the complex shapes involved in modern production design has been increasingly popular. The key to the achievement is a drastic improvement of the dynamic behavior of the machine tool axes used in production machinery. The more complex these tool paths the higher the speed and acceleration requirements. But it is very difficult to reach the target for high speed machine tool because of the limitations of servo system and motion control system. However the direct drive design of machine tool axes, which is based on linear motors and which recently appeared on the market, is a viable candidate to meet the ever increasing demands, because of these advantages such as no backlash, less friction, more mechanical simplicity and very higher acceleration and velocity comparing to the traditional system. This paper focused on the performance tests of the high speed horizontal machine tool based on linear motor. Especially, dynamic characteristics were investigated through circular test and circular form machining test is carried out considering many important parameter. Therefore these several experiments is used to be evaluated the model for prediction of circular motion error and circular machined error.

한국의 지방자치제와 지방분권운동 : 부산지역을 중심으로

최원석 신라대학교 부산학연구센터 2018 부산연구 Vol.16 No.1

This paper begins with the recognition that local autonomy in Korea was not properly operated despite the resurgence of the local autonomy system in 1991, and that the development gap between the national capital region and the province grew larger. Therefore, this paper aims to examine followings: first, what role of central government, local governments and civil society organizations in the region was for the development of local autonomy and decentralization; second, what was the decentralization movements in Busan; third, what are the institutional reform tasks in the next. Despite the implementation of the local autonomy system, Korea stays in the '20 percent autonomy' because of the lack of awareness of the central government on the local autonomy and the lack of will to implement the local autonomy in the local government.There are two decentralization movement groups in Busan's: including “the Busan Innovation Center for Decentralization Movement” and “The Busan Citizens' Solidarity for Decentralization”. While these organizations are making great efforts to decentralize, their organizational capacity does not seem significant. On the other hand, an amendment to the constitution to be made in the future can be an important opportunity for the development of local autonomy and decentralization. Therefore, local governments, local NGOs, and local residents should endeavor for building institutional foundations for substantial development of decentralization, even if the achieving them is difficult. 이 글의 문제인식은 우리나라의 지방자치제가 부활했음에도 불구하고 지방자치는 제대로 시행되지 않았고, 수도권과 지방의 발전 격차는 더 커졌다는 것에서 출발한다. 따라서 이 글의 주요 목적은 첫째, 그러한 상황 속에서 중앙정부와 지방자치단체, 지역사회단체는 어떤 역할을 했는지, 둘째 부산의 지방분권운동은 어떠했는지, 셋째 앞으로 제도적 개선과제는 어떤 것들이 있는지를 살펴보는 것이다. 이를 위해 먼저, 우리나라의 지방자치의 역사와 부활에 대해 살펴보고, 다음으로 지방자치의 의의와 지방분권에 대해 살펴보고, 현재 우리나라 지방자치제도의 문제점과 한계에 대해 살펴보았다. 끝으로 시민운동으로서 부산지역 지방분권운동의 흐름에 대해 살펴보고 향후 제도적 개선과제에 대해 살펴보았다. 우리나라는 지방자치제를 실시했음에도 불구하고 지방자치에 대한 중앙정부의 인식 결여, 지방자치단체의 실천의지의 부족 등으로 ‘2할 자치’에 머무르고 있다. 부산의 분권운동 단체로는 「부산분권운동혁신본부」와 「지방분권부산시민연대」가 있다. 이들 단체들이 지방분권을 위해 많은 노력을 기울이고 있지만, 조직적 역량은 그리 커 보이지 않는다. 한편, 앞으로 있을 개헌은 지방 자치와 분권의 발전을 위한 중요한 계기가 될 수 있다. 그렇기에 지방정부, 지역 시민단체, 지역의 주민들이 많은 역량을 투입해서라도 실질적 지방분권을 마련할 수 있는 제도적 기반을 정초하는 데 앞장서야 한다.

고속가공에서 2중 신경망을 이용한 표면거칠기 예측과 가공DB 구축 효율화 방안

원종률,남성호,유송민,이석우,최헌종 한국공작기계학회 2004 한국공작기계학회 추계학술대회논문집 Vol.2004 No.-

In this paper, a double artificial neural network (ANN) approach and the efficient machining database building scheme are presented for the prediction of surface roughness in high-speed machining. In this approach, 4 machining parameters and used for the prediction of cutting force components, and the combinations of 4 parameters and the predicted cutting force components are finally used for the prediction of surface roughness. The experimental results comparing the these results with the predicted values using simple 4 input nodes have been also investigated to verify the effectiveness of the proposed approach.

수술로 유도된 관절원판의 전방변위시 하악과두 관절연골의 Proteoglycan과 결합단백의 변화에 대한 연구

최원석 대한 두개하악 장애학회 1997 대한두개하악장애학회지 Vol.9 No.1

The purpose of this study was to test the hypothesis that surgical induction of anterior disc displacement(ADD) in the rabbit craniomandibular joints(CMJ) will lead to degenerative osteoarthritic changes in the articular cartilage of the rabbit mandibular condyle by analyzing alterations of proteoglycan molecules and link protein. The quantities of cartilage proteoglycans such as chondrooitin-4-sulfate(C4S), chondroitin-6-sulfate(C6S), keratan sulfate(KS) and link protein(LP) were measured using immunogold labeling technique at the electron microscopic level. The right joint of each of five rabbits was exposed surgically, and all discal attachments were severed except for the posterior attachment. The disc was then displaced anteriorly and sutured to the zygomatic arch. The left joint served as a sham-operated control. Ten additional joints were used as non-operated controls. Deeply anesthetized rabbits were perfused with 2% buffered formalin two weeks after surgery. The mandibular condyles were excised and decalcified in ethylenediaminetetraacetic acid(EDTA). Water-soluble plastic embedded sections were incubated in monoclonal antibuodies directed against C4S, C6S, KS and LP. After incubation in the appropriated colloidal gold conjugated secondary antibodies, tissue sections were studied with electron microscope. The results of the immunocytochemistry using colloidal gold conjugates at the electron microscopic level showed statistically significant declines in C4S, C6S, KS, LP (p<0.05) in the osteoarthritic cartilage. It is concluded that surgical induction of ADD in the rabbit CMJ leads to alterations of the proteoglycan molecules in the articular cartilage of the mandibular condyle similar to those described previously in human ADD and in osteoarthritis of other synovial joints. The results of this study provide evidence that the loss of the shock absorber function of the disc, and the exposure of the condyles to overloading may cause the injured chondrocytes to secrete degenerative cytokines as indicated by the loss of proteoglycans and LP. These molecular changes are expressed at the subcellular and cellular levels as osteoarthritis or degenerative joint disease.

증편 반죽의 냉동 가능성에 관한 연구

최원석,노정옥,우경자 동아시아식생활학회 2003 동아시아식생활학회지 Vol.13 No.6

This study was carried out in order to investigate the possibility of frozen rice batter for the manufacturing of Jeung-pyun. Despite of its unique taste and texture, Jeung-pyun is not consumed much because it needs long time to make. The physicochemical, sensory, rheological and surface characteristics of Jeung-pyun were analyzed to develop the easy manufacture method. The storage condition of rice batter was used at -20℃ up to 4 weeks. Statistical data analysis was completed using a SAS program. The results are summarized as follow: The pH, brix% and sugar content of all samples which added low-temperature tolerance raw yeast or regular raw yeast decreased during the fermentation. Kind of yeast did not influence on the moisture content of the Jeung-pyun batter. Specific volume and carbon dioxide evolution of Jeung-pyun batter were highest when the rice batter was frozen for 1 week regardless of the kind of yeast. Overall quality of frozen batter of Jeung-pyun at -20℃ for 4 weeks had the highest score among different samples. As the test results of mechanical characteristics, cohesiveness, gumminess, brittleness, hardness and springiness did not show any significant differences statistically. The result clearly suggests that freezing the rice batter is a possibile way to manufacture Jeung-pyun.

양측성 관상동정맥루 1예

최용원,오석규,이재훈,이상재,권경희,최은경,김남호,정진원 圓光大學校 醫科學硏究所 2002 圓光醫科學 Vol.17 No.1

저자들은 호흡곤란, 흉부불쾌감, 심계항진 등을 주소로 내원한 환자에서 경흉부 및 경식도 심초음파 검사상 주폐동맥에서 이완기에 전행하는 지속적인 혈류의 흐름을 관찰하고, 관상동맥 조영술을 통해 좌전하행지 중간부위와 우관상동맥 근위부에서 각각 기시하여 공통경로를 이루면서 주폐동맥으로 유입되는 양측성 관상동정맥루를 보이는 드문 1예를 경험하였기에 문헌 고찰과 함께 보고하는 바이다. A coronary arteriovenous fistula is infrequently encountered vascular communication between a coronary artery and a cardiac chamber, a great artery or the vena cava. It is the most common congenital anomaly that can affect coronary perfusion. Bilateral involvement of coronary fistula constitutes an uncommon subgroup of coronary arteriovenous fistulas. A 69 year-old female patient presented with chest discomfort, palpitation, and dyspnea. In the echocardiography, doppler color flow imaging visualized abnormal flow signals with mosaic appearance in the main pulmonary artery during diastolic phase. Coronary angiography revealed arteriovenous fistula arising from the left anterior descending artery and the right coronary artery. Both coronary arteriovenous fistulas drained into the main pulmonary artery. We report a case of bilateral coronary arteriovenous fistula that was confirmed by echocariography and coronary angiography.

사후분해 시체에 대한 법의학적 접근

최영식,이상용,김유훈,조갑래,이봉우,양경무,정낙은,서중석,이한영,이원태,강현욱 大韓法醫學會 2000 대한법의학회지 Vol.24 No.2

Disposal of a homicide victim by dismemberment is rare, but individual cases are on record in most major medicolegal departments. Recognition of postmortem mutilation may be of importance in the interpretation of certain murders committed by sexual perverts and other mentally deranged individuals and sometimes performed for the sole reason of easier disposal of the body. Postmortem dismemberment is usually readily recognizable as such; The edges of the injuries are dry and lack evidence of bleeding. The joints may be disarticulated without fracture, or the use of an axe or saw may be evident from examination of bones. Parallel horizontal or oblique furrows in the bone surface are caused by skipping of the saw prior to establishing depth. Such patterns on the bone may assist in identifying the particular saw involved. So we report 25 dismembered corpses that autopsied in National Institute of Scientific Investigation. This paper can help in attempting to establish not only the first criminal investigation steps but also the medicolegal approach methods in unidentified and dismembered deaths.

시판어묵의 관능적, 기계적 조직감 측정방법간의 비교

최원석,정재현 忠州大學校 2003 한국교통대학교 논문집 Vol.38 No.2

The optimum conditions for the measurement of texture profile of commercial Kamabokoes were investigated by Texture analyser and the data were compared to those of sensory evaluations. Significant correlations between sensory evaluation and mechanical measurement were observed in hardness, cohesiveness, chewiness and gumminess. The optimum conditions for the mechanical measurement instead of sensory evaluations of Kamaboko were the 70% compression ratio with a flat probe(φ 24.6 mm) at 2.4 mm/s cross head speed

FIB를 이용한 나노가공공정 기술 개발

최헌종,강은구,이석우,홍원표 한국공작기계학회 2004 한국공작기계학회 춘계학술대회논문집 Vol.2004 No.-

The application of focused ion beam (FIB) technology in micro/nano machining has become increasingly popular. Its use in micro/nano machining has advantages over contemporary photolithography or other micro/nano machining technologies, such as small feature resolution, the ability to process without masks and being accommodating for a variety of materials and geometries. This paper presents that the recent development and our research goals in FIB nano machining technology are given. The emphasis will be on direct milling, or chemical vapor deposition techniques (CVD), and this can distinguish the FIB technology from the contemporary photolithography process and provide a vital alternative to it. After an introduction to the technology and its FIB principles, the recent developments in using milling or deposition techniques for making various high-quality devices and high-precision components at the micro/nano meter scale are examined and discussed. Finally, conclusions are presented to summarize the recent work and to suggest the areas for improving the FIB milling technology and for studying our future research.

혐기 및 2단 교호(交互) 간헐포기조를 이용한 하수고도처리에 관한 연구 : 파일럿 규모의 실험결과를 중심으로 A Pilot-scale Study

최용수,홍석원,권기한 한국물환경학회 2004 한국물환경학회지 Vol.20 No.3

The performance of a newly designed wastewater treatment process equipped with an anaerobic and two intermittent aeration tanks operated alternately was investigated. During the experimental period, several types of cyclic operating schedules with different aeration and non aeration time were examined for the optimization. At all modes, the removals of organic matter and SS were highly achieved. With respect to T-N removal, however, the cycle length for aeration on/off affected the efficiencies. At the optimal operating mode, the ORP bending point indicating the disappearance of nitrate was observed. Considering the influent wastewater characteristics and cyclic operating schedules, it can be suggested that T-P removal is much more BOD/T-P ratio and/or its load dependant rather than the aeration on/off time. The results obtained from pilot-scale test showed the competitive advantage of this alternating process through an omission of nitrate recycle and operational flexibility against influent load variations when comparing with other continuous flow processes.