최적설계 기법을 적용한 1톤 운반차용 P.T.O축 및 트랜스미션 개발에 관한 기초연구

김재열,심재기,최승현,정효희,김훈조,오현중,박경섭 한국공작기계학회 2007 한국공작기계학회 추계학술대회논문집 Vol.2007 No.-

Now, power tillers and cultivators which are spread among fruit tree households have usage, low application, and high accident risk. Therefore, the development of multi-purpose work vehicles is needed as an alternative for these problems. Especially, easy usage and the ability to easily change gears when driving and the development of the P.T.O for various tasks such as pruning, water lifting, pest control, application and, mowing are needed. In this research, we will develop a transmission with design on P.T.Oaxle for agricultural work vehicles including multi-purpose vehicles. We aim to develop a 4-wheel drive transmission of synchronous contact type for practical use in fruit tree households which is required to be a large-sized agricultural vehicle. Therefore, we have per performed as follows that are composed of load capacity from 500kg to 1,000kg, safety securing for passengers, and drive securing under bad conditions of the topography slope and swampy land and the rest. For this purpose, we have developed a prototype vehicle through strength analysis of transmission design. we have selected optimal design conditions (Optimal RPM and torque according to some works) on the power transmission with multi-purpose vehicle for various jobs: spraying, manure spreading, mowing, brush wood chopping. If development of the P.T.O containing variable RPM and torque is successful, the following tasks can be possible. Air pruning, air maintenance, water lift, pest control, application, mowing, spraying, and brush wood chopping are possible with this developed P.T.O. Methods and contents for research are followed. Therefore, we have achieved performance-tests through the prototype of the multi-purpose work vehicle and have improved on troubles by the analysis of results of R&D. Also, we provided solutions to problems in mass production in the future.

측두하악 관절의 재건을 위한 늑연골 이식의 효과

김태규,정기돈,신상훈,김성길,이성근,박상준,서종천 大韓顎顔面成形再建外科學會 1996 Maxillofacial Plastic Reconstructive Surgery Vol.18 No.3

We performed costochondral grafting in mmandibular reconstruction including condyle replacement in 5 patients which have 4 cases of ameloblastoma, 1 case of resorption of left condyle due to osteomyelitis. We harvested the 6 th costochondral cartilage of unaffected side. No specific complications were appeared with unexpected fracture of costochondral junction and infection of operation site, These patients show 30-45mm at month opening, near normal of affected side, near normal or normal of unaffected side at lateral excursion. Postoperative coureses was uneventful with improved cosmetic and functional results. Our report is indicated that the costochondral graft is satisfactory to reconstruct mandibular defect including condyle replacement, especially in growing patients.

사이토카인과 Lipopolysaccharide 자극에 의한 RAW 264.7 세포주의 nitric oxide 생성

김영덕,전창덕,이병순,이복수,박석돈,백상기,정헌택 충남대학교 생물공학연구소 1993 생물공학연구지 Vol.3 No.-

Macrophages have been implicated as a major class of effector in the host response to neoplasia. Cells of the monocyte-macrophage lineage are known to exhibit tumoricidal activity following stim-ulation by γ-interferon, tumor necrosis factor, BCG and bacterial products such as lipopoly-saccharide (LPS). While the mechanism involved remain obscure, the generation of reactive nitrogen intermediate (RNI) by activated macrophages is considered a maior participant in mediating the tumorstatic effect. But much of what is known about the induction and release of RNI has been elucidated by using freshly isolated cells from blood and other tissues of experimental animals. In this study, we used a murine macrophage cell line, RAW 264.7, and found that these cells showed above 99% positive of pan macrophage marker by immunohistochemical staining. These cells could produce nitric oxide (NO), when incubated with γ-IFN or poly I:C. Incubation of RAW 264.7 cells with γ-IFN for 48 hous in the presence of LPS agumented NO release in a dose dependent manner. Whereas, treatment of anti-TNE-α antibody or antisense TNF-α oligodeoxynucleotide inhibited the release of NO_2 by γ-IFN plus LPS activated macrophages. The production of NO was also inhibited reversibly or irreversibly by N^GMMA,NAA,arginase or DPI. Thease data suggest that RAW 264.7 cell line may be useful for the in vitro evalulation of biological response modifiers as well as the study of signal pathway of NO release by macrophages.

표준물질 조제를 위한 퇴적물 중 유기염소제 농약 및 Poiychlorinated Biphenyls의 분석

김미옥,이성인,정기호,소헌영 부산대학교 환경문제연구소 2002 環境硏究報 Vol.20 No.-

Standard reference materials(SRM) have been used to certify the degree of accuracy for determining various kinds of analytes including environmental organic contaminants. In this study, we collected sediments from the Nakdong River estuary and Ulsan Bay. The levels of polychlorinated biphenyls(PCBs) and organochlorine pesticides were determined to investigate the availability of SRM and its homogeneity. The 8 congeners of PCBs and chlordane, p,p'-dichlorodiphenyldichloroethane(DDD), p,p'-dichlorodiphenyldichloroethylene(DDE), p,p'-dichlorodiphenyltrichloroethane(DDT), dieldrin, hexachlorobenzene(HCB) and oxychlordane were determined by using a capillary column gas chromatography/electron capture detector system. The environmental levels of these species md their relative standard deviations are discussed.

CT 스캔 영상재구성과 개인용 컴퓨터를 이용한 영상 재형성과의 비교에 관한 연구

김상준,김은경,정기훈 大韓口腔顎顔面 放射線學會 1994 Imaging Science in Dentistry Vol.24 No.2

Radiographic planning is needed for implant placement in order to determine implant length, jaw bone volume, anatomical stucture nd so on. Radiographic examination includes conventional radiography, conventional tomography and CT scan. The most accurate mesurement can be obtained from CT scan. For the cross-sectional view of mandible, CT scan reconstruction is generally needed. But the cross-sectional view of mandible can be reformed by personal computer. This study was performed to examine the clinical usefulness of reformed image using personal computer in comparison with CT scan reconstructed image. CT axial slices of 4 mandibles of 4 volunteers were used. Digital imaging system was composed of Macintosh Ⅱ ci computer, high resolution Sony XC-77 CCD camera, QuickCapture frame grabber board and "NIH Image" program. Seven reconstructed cross-sectional images within CT machine(CT group) were obtained. And seven reformed cross-sectional images(PC group) after digitization of CT axial slices into the personal computer were obtained. PC group was compared with CT group in the objective and subjective aspects. The results were as follow: 1.Measurement of mandibular height & width in both group showed insignificant difference(p>0.05). 2.Subjective assessment of the mandibular canal in both group showed insignificant difference(p>0.05). 3.Image reformation using personal computer could provide panoramic view, which could not be obtained in CT scan reconstruction.

치과병원에서 사용되는 진단영상에 대한 JPEG 2000 압축률에 대한 평가

정기훈,한원정,유동수,최순철,김은경 대한구강악안면방사선학회 2005 Imaging Science in Dentistry Vol.35 No.3

Purpose : To find out the proper compression ratios without degrading image quality and affecting lesion detectability on diagnostic images used in dentistry compressed with JPEG 2000 algorithm. Materials and Methods : Sixty Digora periapical images, sixty panoramic computed radiographic (CR) images, sixty computed tomographic (CT) images, and sixty magnetic resonance (MR) images were compressed into JPEG 2000 with ratios of 10 levels from 5 : 1 to 50 : 1. To evaluate the lesion detectability, the images were graded with 5 levels (1: definitely absent; 2: probably absent; 3: equivocal; 4: probably present; 5: definitely present), and then receiver operating characteristic analysis was performed using the original image as a gold standard. Also to evaluate subjectively the image quality, the images were graded with 5 levels (1: definitely unacceptable; 2: probably unacceptable; 3: equivocal; 4: probably acceptable; 5: definitely acceptable), and then paired t-test was performed. Results : In Digora, CR panoramic and CT images, compressed images up to ratios of 15 : 1 showed nearly the same lesion detectability as original images, and in MR images, compressed images did up to ratios of 25 : 1. In Digora and CR panoramic images, compressed images up to ratios of 5 : 1 showed little difference between the original and reconstructed images in subjective assessment of image quality. In CT images, compressed images did up to ratios of 10 : 1 and in MR images up to ratios of 15 : 1. Conclusion : We considered compression ratios up to 5 : 1 in Digora and CR panoramic images, up to 10 : 1 in CT images, up to 15 : 1 in MR images as clinically applicable compression ratios.

L - NAME 주입시 신 교감신경이 신혈류량 변화에 미치는 영향

민영기,양훈모,이석호,김종규 순천향의학연구소 2000 Journal of Soonchunhyang Medical Science Vol.6 No.2

Recently it is known renal medullar will be play a important role of blood pressure control and pressure natriuresis. Renomedullary antihypertensive mechanism is activated by increasing perfusion pressure of kidney and can be inhibited by sympathetic nerve stimulation or blockade of nitric oxide(NO) formation. It is important to know what is affect on renal regional blood flow, especially renal medullary blood flow(MBF). For the purpose of investigating the effect of the renal sympathetic nerve on regional blood flow during infusion of blocking NO synthesis(by N^(ω)-nitro-L-arginine methylester:L-NAME) in spontaneous hypertensive rat(SHR) and Wistar rats normal control, Mean arterial pressure(MAP), total renal blood flow(TRBF), midcortical blood flow(CBF), inner medullary blood flow were measured in innervated or denervated renal sympathetic nerve group of SHR and Wister rats. All group that received the L-NAME were seen increasing MAP while TRBF, CBF and MBF decreased and the decrease of TRBF in SHR is more marked than in Wistar rat. In spite of increasing the MAP, MBF in all four group decreased, respectively C: 220 ± 3 U, 205 ± 2 U Wi : 215 ± 4 U, 165 ± 12 U Wd :218 ± 3 U, 170 ± 10 U Si :195 ± 4 U, 98 ± 15 U Sd : 200 ± 3 U, 120 ± 14 U, especially the most remarkable decrease about 50 % in SHR innervated group. Thus, according to these result, NO seems to maintain the MBF and the partial interaction between renal sympathetic nerve and NO in medullary blood flow can be suggested in innervated SHR.

실시간 차량경로결정을 위한 동적 최단경로 알고리즘

宋省薰,金基燮 弘益大學校 科學基術硏究所 1999 科學技術硏究論文集 Vol.10 No.2

During times of traffic congestion, the traffic network in a transient, time-dynamic state resembles a dynamic network. In addition, in the context of Intelligent Transportation Systems(ITS), the network can accurately detect such transient behavior using traffic sensors, and several other information gathering devices. In the time-varying traffic situation, the rapid calculation of user-optimal, system optimal and multiple optimal routes is necessary. In this research, several existing shortest path algorithms were reviewed. And we suggest a systematic procedure to find a dynamic shortest path using k-shortest path algorithm and genetic algorithm. The suggested procedure can be also applied to calculate user-optimal path for vehicle scheduling and dispatching problems.

O-링 테스트의 정량화에 관한 연구

최기훈,여인철,김영탁 중앙대학교 생산공학연구소 2000 생산공학연구소 논문집 Vol.9 No.2

신체의 건강진단을 위해서는 값비싼 장치의 전문지식이 요구된다. 따라서 장비를 갖춘 병원과 같은 특정 장소에서 전문지식을 가진 의사를 만나기 위해 시간과 노력을 들여 이동해야만 한다. 그러나 최근에는 간단하게 진단을 할 수 있는 장치가 개발되어 있다. 0-링 테스트는 특별한 장치가 없이도 간단한 지식으로 건강진단 및 약물이나 음식물의 이해 여부를 판단할 수 있는 유효한 진단방법으로 인식되고 있다. 하지만 이 테스트 법은 검사자의 경험과 주관에 의존하므로 결과에 대한 신뢰성과 객관성이 문제시되고 있다. 본 연구에서는 0-링 테스트 시스템을 고안하여 테스트결과가 객관적이고 정량적으로 나타나도록 하여, 손쉽게 결과를 판단 할 수 있게 하고자 한다. It is usual that the medical examination of human body need special knowledge and equipments. Thus we have to spend time and energy on going to special place such as hospital where doctors and equipments are. Which often cause missing a good chance of medical treatment as well as giving us inconvenience. However many simple and convenient equipments were developed for checking our health conditions recently. 0-ring test is accepted as one of useful methods to examine our health conditions. Also the test is recognized as a useful means to judge, without any special equipment and medical knowledge, if some medical substances or foods are beneficial or harmful to our health. However, the judgement may be incorrect because it depend on doctor's subjective point of view. In this study, we developed an automatic 0-ring test machine which enable us to check our health conditions objectively and quantitatively. The validity of the idea to develope the machine was proved by experiments.

특이한 악관절 강직증 : 진성 악관절 강직증과 상악골과 하악골 사이의 골성 유합

서재훈,조세인,여환호,이기혁,김영균 大韓顎顔面成形再建外科學會 1995 Maxillofacial Plastic Reconstructive Surgery Vol.17 No.2

TMJ ankylosis is classified with true and false type. A true ankylosis is defined as any condition that produces fibrous or bony adhesions between the articular surfaces of the temporomandibular joint. The main causes of true ankylosis are trauma or infection. A false ankylosis results from pathologic conditions outside the joint that limit mobility of the mandible such as myogenic disorders, coronoid impingement or rare direct bony fusion between maxilla and mandible. The treatment of choice of TMJ ankylosis is surgical intervention. We experienced the male patient with complete mouth opening limitation since 45 years before. This patient has true TMJ ankylosis and rare bony synostosis between maxilla and mandible in the right posterior region. We performed surgical intervention and had a favorable result.