工業團地內 새마을運動 共同推進方案에 관한 硏究

金千鎰,裵源達,林德相,張晩植 효성여자대학교 새마을연구소 1989 새마을硏究論文集 Vol.9 No.-

닥터소음의 피드포워드제어에 관한 연구

김천덕,차경환 釜山水産大學校 1989 釜山水産大學 硏究報告 Vol.29 No.1-2

This paper has described the efficiency for the new method of the active control of the duct noise which is adaptive filtering application by experiment which set the additional sound source. Firstly the active noise control system becomes stable since the acoustic feed back quantity can be set under -30 dB by setting the additional sound source at an excite of duct and for the signal which is supplied to additional sound source by the setting the microphone at the upstream of duct. Secondly, since the noise of duct output and additional sound source constructs dipole source, radiating power will be decreasing over all the direction in comparison with the case without the additional sound source in the range of frequency which the distance between the duct and the additional sound source is shorter than wave length that is a center frequency of the duct noise. The result of noise cancelling amount for simulation and fan noise experiment by the active control system has been attenuated about 5∼6 dB by only using the proposed active control system and about 9∼10 dB can be attenuated by using adaptive filtering algorithm with the proposed active control system on the desired frequency band.

요하지통 환자에서 두 개의 캐눌라를 이용한 박동성 고주파 신경근 응고술의 임상 연구

김천숙,배재영,배덕구,강규식,안기량,권진형,김지은,유시현 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.1

Dorsal root ganglion(DRG) block by the local anesthetics and steroids which has done classically in low back pain(LBP) patients with radiculopathy has high incidence of recurrence rate and side effects of steroids. Recently a new technique of pulsed radiofrequency thermocoagulation(P-RFTC) was introduced and substituted for it because of the benefits such as relatively low recurrence rate, low risk of nerve injury and comfort during the procedure. We experienced 15 patients who had LBP with radiculopathy and no or little response to epidural steroid injection. When we performed DR ganglionotomy by P- RFTC under the C-arm guide in these patients, we tried to approach the exact DR ganglion using tow cannulas - the one for obtaining patient's subjective symptoms and injection of contrast dye, the other for making a RF lesioning after identifying the impedance of sensory and motor stimulation. In conclusion, DR ganglionotomy by P- RFTC using two cannulas in LBP patients is an easy and safe procedure with satisfactory results.

점화시기가 LPG 엔진의 배기특성에 미치는 영향

한덕수,장영민,전봉준,김성준 강원대학교 산업기술연구소 2006 産業技術硏究 Vol.26 No.A

As an automobile fuel, LPG has many environmental advantages compared to gasoline or diesel. However, current LPG engine which is provided with LPG fuel as gas form has lower power and worse fuel efficiency than gasoline engine. These problems of low power and bad fuel efficiency come from lower volumetric efficiency. Also there is a new rising problem of high failure ratio in an engine emission test. Although there are many factors which affect engine performance of exhaust gas emission, one believes that the fact that ECM of gasoline engine is used for LPG engine when retrofitting gasoline engine to LPG engine is one of the main problems, which lower engine power and emit more noxious gas due to wrong ignition timing. To solve these problems, one studied the effects of ignition timing on the exhaust gas to find out the optimum condition of ignition timing. The experimental results show that noxious exhaust gas is reduced and engine power is increased if the optimum control of ignition timing is applied in accordance to the revolution speed of engine.

점화시기가 LPG 엔진의 배기특성에 미치는 영향

한덕수,장영민,전봉준,김성준 강원대학교 산업기술연구소 2006 産業技術硏究 Vol.26 No.B

As an automobile fuel, LPG has many environmental advantages compared to gasoline or diesel. However, current LPG engine which is provided with LPG fuel as gas form has lower power and worse fuel efficiency than gasoline engine. These problems of low power and bad fuel efficiency come from lower volumetric efficiency. Also there is a new rising problem of high failure ratio in an engine emission test. Although there are many factors which affect engine performance of exhaust gas emission, one believes that the fact that ECM of gasoline engine is used for LPG engine when retrofitting gasoline engine to LPG engine is one of the main problems, which lower engine power and emit more noxious gas due to wrong ignition timing. To solve these problems, one studied the effects ignition timing on the exhaust gas to find out the optimum condition of ignition timing. The experimental results show that noxious exhaust gas is reduced and engine power is increased if the optimum control of ignition timing is applied in accordance to the revolution speed of engine.

삼각피판법과 밀라드씨법을 겸한 술식에 의한 선천 성구순열교정의 치험예

강동훈,전건수,김덕래 大韓成形外科學會 1987 Archives of Plastic Surgery Vol.14 No.1

There are several well established methods of primary cleftlip repair. Nowadays, traingular flap method and rotation advancement flap method are most widely used and regarded as a method of choice for the repair of cleft lip. However, in cases with severe vertical height difference between cleft side and non cleft side, both methods have some problems. With the Millard`s method for the repair in these cases, the incision of rotation flap must be extended to the philtral column on the noncleft side. This induces a break in the upper part of philtrum and it is not always easy to achieve smooth continuity of the Cupid`s bow. With the triangular flap method for the repair in these cases, large traingular flap has to be designed for lengthening. It produces fairly noticeable scar on the philtrum and divides the philtrum into two parts. Onizuka reported a method in which a small triangular flap was added together with that of Millard in 1966. Y, Nishimura modified Onizuka method in 1978. We performed a method in which triangular flap was put on the end of vermilion ridge with Millard`s method for the repair of cleft lip in cases which vertical hight differences are severe, usually more than 5mm in length in the infant. The result of this method is proved to be very successful and eliminates or reduces the problems previously described. ―Advantages of this method― 1. Permit lengthening even in severe forms without making large z-plasty scar in the philtrum. 2. Preserve philtral dimple and column better than triangular flap method. 3. Natural appearence of the upper part of philtrum. 4. Better correction of nasal deformties than triangular flap method. 5. Good muscle anatomic realignment. 6. In the Second stage operation of bilateral cleft lip, expected lengthening can be achieved without making protrusion of the lower margin of the prolabium.

소형 DC 모터의 음향신호 분석에 관한 연구

이채봉,김천덕 東西大學校 2002 동서논문집 Vol.8 No.-

The detection of small DC motor has been carried out mainly by field engineering using their ears or sense, but it is not resonable. This paper describes a study on development of real time flaws discrimination system in small DC motor using their sound signal analysis. On this subjects, some automatic methods have been researched, which are based on the analysis of the periodicity of the acoustic signal over a time window longer than the repetition interval of the signal. But it is hard to detect the signal by those methods. And those methods have not yet reseached the stage or practical use. A new method is proposed, in which the envelope of the power of narrow band signals are calculated, and periodicity of the interval of the signal is detected. The method can be applied in the cases where the period of flaw pulse is irregular and/or the frequency of flaw pulse is apart from the distinguished frequency components of the acoustic signal.

전기자극이 건의 치유에 미치는 영향에 관한 실험연구

홍성철,김덕래,김태연,정전은,박길홍 大韓成形外科學會 1991 Archives of Plastic Surgery Vol.18 No.1

The mechanism of tendon healing has been a controversial issue. Although there seems to be a dipolarizing opinion regarding the tendon healing, it is well known to us that the tendon has both intrinsic and extrinsic healing capacity which has proved in vivo and in vitro studies. Tendon adhesion is a common sequella after tendon repair, particularly after the ling period of immobilization. This can be explained by one wound concept or extrinsic tendon healing. If we can modify the natural healing process of the tendon by augmenting the intrinsic capacity, we can reduce the period of immobilization to allow early motion for better gliding. in this study, we used the electrical stimulation technique, which has been known to have good growth stimulatory effect on the living cells, to investigate its effect on tendon healing in organic culture for 6 weeks. Total 64 flexor tendons were harvested from 8 rabbit paws and they were cultured in separate petri-dishes.: 32 tendons were used for the control group and the rest 32 were used for the electric stimulation group. Tendons through which a continuous 7 μAmp current was passed at the repair site were compared with the non stimulated controls. In reference to the histologic study with Hematoxylin ?? Eosin stain and van Gieson stain, the following results were obtained. 1. There was found no necrosis in the specimens of the control as well as the elctrical stimulation group during 6 weeks' culture period. 2. Starting from 1 week, there was prominent increase of fibroblastic proliferation and collagen production in electrical stimulation group and these active repair processes persisted up to 6 weeks. Accordingly, I conclude that the intrinsic tendon healing capacity can be enhanced by the electrical stimulation in vitro.

PCB조립 라인의 준비 시간 단축 및 재고품 감소를 위한 스케줄링 전략

이영해,김덕한,전성진 한국경영과학회 1997 韓國經營科學會誌 Vol.22 No.1

Printed circuit board (PCB) assembly line configuration is characterized by very long set-up times and high work in process(WIP) inventory level. The scheduling method can significantly reduce the set-up times and WIP inventory level. Greedy sequence dependent scheduling (GSDS) method is proposed based on the current methods. The proposed method is compared with the current method in terms of three performance measures: line throughput, average WIP inventory level, and implementation complexity.

동전형 수중스피커의 전기(동)임피던스 해석에 의한 등가회로 모델링

이채봉,이창영,김천덕 동서대학교부설연구센터 2001 연구센터논문집 Vol.4 No.1

Fisheries policy change from catching to farming requires more intensive consideration for aquaculture industry. The oceanic farm is a desirable cost effective aquaculture method. However, in order to gather fish in the oceanic farm, eating sound or any attracting sound should be radiated through underwater loudspeaker. In this paper, we researched the frequency range responding to fish and electrical impedance estimated by computer simulation on prototype underwater loudspeaker using equivalent circuit technique. It has been found in literature that the frequency range responding to fish is about 16Hz to 13kHz but sensitive frequency range is about 150Hz to 2kHz and sound pressure level is about 100dB to 150dB reference 1μbar. Therefore, frequency range and output sound level of designed underwater loudspeaker has been specified as 150Hz to 3kHz and 100dB to 145dB reference 1μbar, respectively. Electrical impedance of computer simulation is founded 789 for 629Hz using equivalent circuit technique.