고성능 디지털전원장치에 관한 연구

김윤식(Y.S Kim),하기만(K.M Ha),이성근(S.G Lee),오진석(J.S Oh),이홍찬(H.C Lee) 한국마린엔지니어링학회 2006 한국마린엔지니어링학회 학술대회 논문집 Vol.2006 No.-

Digital power supply controller using the Digital Signal Processor (DSP) and Field Programmable Gate Array (FPGA) has been developed over the years. Recently, full digital power supply controller has been studied and tested. A new digital controller is designed under 3U euro-standard size and provides quiet better overall performance characteristics than the standards of ± 5 ppm short-term stability (< 1 min) and ± 25 ppm long-term stability (< 12 hours). The digital controller adopted digital PID current control algorithm with single pole digital filter and feed-forward voltage ripple compensation loop. By implementation of the digital controller, it has the ability of high step resolution (150 ps) Digital Pulse Width Modulation (DPWM) for FET or IGBT switch drivers and high resolution (18-bit, 400 kSPS/2 MSPS) analogue to digital conversion for current and voltage signal measurement. In this paper, the hardware and software structures of the developed digital controller and experimental results of digital power supply are described.

누에의 인공사육개발(人工飼育開發)에 관(關)한 연구(硏究)

김윤식 ( Y. S. Kim ) 한국잠사학회 1972 한국잠사곤충학회지 Vol.14 No.2

사료 조성에 건물량의 반량가량 상엽분말을 혼합하여 조제한 인공사료육에서 좋은 성적은 얻지 못했다고 할지라도 인공사료육은 가능하며 앞으로의 연구에 기대한다. 특히 무균사육은 잠사과학 연구 발전에 공헌할 수 있을 줄 생각된다. (1) 발육속도가 부진한 것은 사육온도와 사료의 물리적 성질과도 관계가 있다고 생각되며 사료의 수분율은 높고 누에의 사육온도는 섭식을 촉진할 수 있는 생리에 크게 해롭지 않는 적온 내지 30℃의 고온이 좋다고 생각된다. (2) 무균사육잠의 발육은 자연폭로의 인공사육잠보다 완만하며 이것은 방부제에 의한 장해라고 생각된다. It was first succeed in rearing the silkworm on the artificial diets in Japan in 1960. Since then, the researches on the artificial diets have been carried out intensively but the artificial diets have not been applied to the silkworm rearing practically till now. There are difficulties in rearing the silkworm on the artificial diets, such as uneven silkworm growth, higher production cost and decay. The results were not satisfactory, but the author hopefully expects that the artificial diet rearing would be possible for maintaining normal silkworm growth throughout improvement of diet composition, rearing techniques and aseptics add to the diets. Especially the author considered that the aseptic rearing will contribute to the research of sericultural science. Within a few years, the artificial diet rearing would be applied to the practical silkworm rearing.

2차원 날개 주위의 지면효과에 대한 난류 유동장 해석

김윤식(Y.S. Kim),이재은(J.E. Lee),신명수(M.S. Shin),강국진(K.J. Kang),권장혁(J.H. Kwon) 한국전산유체공학회 2006 한국전산유체공학회지 Vol.11 No.4

Two dimensional turbulent flow simulations on the low Mach number - high Reynolds number flow about the NACA 4412 airfoil are carried out as the airfoil approaches a ground. It has turned out that angle of attack between 2 and 8 degrees is recommended for the airfoil to utilize the benefit of ground effect. For the large angle of attack, the increment of lift due to the ground effect is faded away and negative aerodynamic effect such as destabilizing aspect in static longitudinal stability occurs and the separation point moves to forward as the airfoil approaches a ground.

상호 대화형 격자 생성 환경을 이용한 항공기 전기체 격자계 생성

김윤식(Y.S. Kim),권장혁(J.H. Kwon) 한국전산유체공학회 1999 한국전산유체공학회 학술대회논문집 Vol.1999 No.-

An Interactive grid generation program(KGRID) with graphical user interface(GUI) has been improved. KGRID works on the UNIX environment and GUI has been implemented with OSF /Motif and X Toolkit and the graphics language is OpenGL for visualization of the3D objects. It supports more convenient user environment to generate 2D and 3D multi-block structured grid systems. It provides various useful field grid generation methods ,which are the algebraic methods, the elliptic partial differential equations method and the predictor corrector method. It also supports 3D surface grid generation with NURBS(Non-Uniform Rational B-Spline) and various stretching functions to control grid points distribution on curves and surfaces. And some menus are added to perform flexible management for the objects. We generated surface and field grid system about full aircraft configuration using KGRID. The performance and stability of the KGRID is verified through the generation of the grid system about a complex shape.

원전 안전등급 비상디젤발전기 속도제어시스템 성능개선 및 분석에 관한 연구

김윤식(Y.S Kim),전일영(I.Y Jeon),이성근(S.G Lee),김창국(C.K Kim),안진우(J.W Ahn) 전력전자학회 2005 전력전자학술대회 논문집 Vol.- No.-

The paper is final report for speed control upgrade and analysis report which recently performed on PWR NPP safety related EDG KHNP Ulchin NPP No.2 Unit. The upgraded system includes more beneficial function like as "Slow start with starting ramp", "Generator load sensing & control capability" and "Emergency ramp during slow start". This paper shows functional operation of slow start regime according to NRC regulatory guide which guide regulation to NPP safety related environment.

잠종(蠶種)의 질(質)이 잠작(蠶作)에 미치는 영향에 관한 연구(硏究)

김윤식 ( Y. S. Kim ),김문협 ( M. H. Kim ),박광의 ( K. E. Park ),이상풍 ( S. P. Lee ),강석권 ( S. K. Kang ),성수일 ( S. I. Seong ) 한국잠사학회 1972 한국잠사곤충학회지 Vol.14 No.2

춘추잠기를 통하여 잠기별로 성적이 좋은 항목과 여타항목 성적간의 관계를 보면 일정한 경향을 발견할 수가 없으므로 종합적인 고찰을 하기가 지극히 곤란하나 대략 다음과 같이 요약할 수 있겠다. (1) 월년잠종 냉장입고시의 배자 발육계제와 부화율 및 실용부화율간에는 어떠한 경향을 발견할 수가 없다. 그러나 부화율이 좋지 못한 잠종은 실용부화율이 낮을 뿐만 아니라 상견수견량이 적고 또한 화용률도 낮다. 실용부화율이 좋지 못한 잠종은 유화율이 약간 낮은 경향이 있으나 상견수견량과 부화율은 평균치 이상이거나 평균치에 근사하다. 따라서 실용부화율은 누에의 건강과는 관계가 적다고 할 수 있겠다. (2) 오교율은 상견수견량과 화용율에 영향을 미치리라고 생각되며 오교율이 높아지면 원잠이나 원잠견의 혼입률이 높아지는 것이다. 그리고 오교율은 잠견제조에 속하는 문제이며 양잠의 양적 및 질적 생산에 영향을 미치는 요인이라고 하겠으나 여건에 따라서는 원종과 교잡종간에 현격한 차가 나타나지 않는 것이라고 생각된다. 또한 월년잠종과 불월년잠종간의 평균오교율차는 교잡원종의 순도에 기인한 것이라 생각된다. (3) 상견수견량이 적은 잠종은 화용율이 낮은 경향이 있으니 상견수견량과 화용율간에다 관계가 있다고 생각된다. (4) 견층비율이 낮은 잠종은 화용율이 낮아지는 경향이 있다고 하겠다. 따라서 견층비율은 잠품종적인 문제 이외에 잠작과도 유관하다고 생각된다. The authors studied on the effect of silkworm eggs collected from the whole silkworm egg producers in Korea to know the cocoon crops, and the results are as follows. There was no remarkable correlation on the effect of silkworm eggs quality for the cocoon crops but can be concluded as follows. 1) There was a weak correlation between the hatching ratio and economical hatching ratio but no correlation between economical hatching ratio and cocoon crops. In other word, hatching ratio couldn`t be influenced for the silkworm health. 2) Non-hybrid ratio (miss-crossing ratio) influenced to the amount of reelable cocoons and pupation ratio but on this experiment, there was a little influence for the cocoon crops. The authors found that there is no difference between origin and its F1 crops under the more suitable conditions. Non-hybrid ratio can be determined the silkworm eggs quality, but notice that the ratio decrease only when used pure origin. 3) There is some correlation between harvesting amounts of reelable cocoon and pupation ratio. In general, the eggs which harvest small amounts of reelable cocoon are lower on the pupation ratio. 4) The influence of cocoon layer ratio is based on the variety absolutely but cocoon crops also has a little influence on the cocoon layer ratio.

종견(種繭)의 절개(切開)와 발아율(發蛾率) (탈견율(脫繭率))간(間)의 관계연구(關係硏究)

김윤식 ( Y. S. Kim ) 한국잠사학회 1971 한국잠사곤충학회지 Vol.13 No.2

In the silkworm egg production, cutting of the cocoon`s edge formed by silkworms forced to aid the emergence, and emergence is related to the amount of alkaloid liquid in the sucking stomach in certain varieties. In this study, there was no difference between cutting of portion and sex, and no significant between cutting of both sides and one side cocoons when comparing their emergence ratio. Expenditures and emergence ratio between both sides and one side cutting off must be studied in coming future.

지도가 주어진 실내 주차장에서 레이저 센서를 이용한 자차 위치인식 알고리즘

김윤식(Y. S. Kim),홍대희(D. Hong) 한국정밀공학회 2016 한국정밀공학회 학술발표대회 논문집 Vol.2016 No.10월

탈피(脫皮) Hormone의 누에 숙화(熟化) 촉진(促進)에 관(關)한 연구(硏究)

김윤식 ( Y. S. Kim ) 한국잠사학회 1971 한국잠사곤충학회지 Vol.13 No.2

1. Ecdysterone의 숙화 촉진작용은 5령 성식기이후에 유효하다. 2. Ecdysterone은 누에의 숙화를 촉진하고 또 초숙잠과 종숙잠간의 시차폭을 축소시킨다. 3. Ecdysterone의 숙화 촉진작용은 Ecdysterone의 식하량과 비례한다. 4. Dodecyl alcohol 주제의 DAT는 등족작용을 촉진한다. 5. Ecdysterone과 Dodecyl alcohol의 병용은 숙화와 등족을 촉진하여 자연상족을 가능케 하며 상족기술 개량에 공헌할 줄 믿는다. It is very important to make mounting numerous silkworms by their normal growth when considering the sericultural management. There were several studies on the utilization of repellent to the matured silkworms to mounting, studies concerning forcing maturity of silkworms were developed considerably after studies on the insect ecdysis hormone. Commercial named MSH(II) (Inoksterone) similar substance of ecdysterone and DAT repellent (Dodesil alcohl) were used for this study, and the results can be summarized as follows; 1. MSH (II) mixed with the mulberry leaves shown the matured effect on the growth of silkworms and increased amount of MSH (II) shortened the last stage in their growth. 2. MSH (II) mixed with the mulberry leaves when 5% of early matured silkworms appeared were most effective. 3. DAT was hastened their mounting. 4. Utilization of MSH (II) and DAT together were hastened silkworms mounting and those chemicals can be used practically in the silkworm rearing.

인위적(人爲的) 유발(誘發)에 의(依)한 가잠(家蠶) 중장형다각체병(中腸型多角體病)의 연구(硏究)

김윤식 ( Y. S. Kim ) 한국잠사학회 1964 한국잠사곤충학회지 Vol.4 No.-

本試驗은 中腸型多角體病이 果然 우리나라에서도 傳染하는가를 알기 爲하여 實施한 것이다. 그 結果 우리나라에서도 이것이 傳染함을 알았기에 이를 報告한다. 1. 여러 가지 人爲的 誘發處理에 依하여 中腸形多角體病이 誘發되며 其中에서도 5領 起蠶을 餉食 適期에 低溫處理한 것이 (5℃, 24時間) 가장 效果的이었다. 2. 秋蠶期 普通飼育蠶에서도 該蠶病이 發生하였으니 飼育中의 모든 惡條件의 總和가 誘因이 되어서 發病한 것이라고 하겠다. It is well known that the mid gut polyhedroses can be a cause of serious disease of silkworm in Japan. In our country, however, this disease has not been discussed up to the present. Author made the experiments to know whether this disease was infectious or not in our country. The results are as follows: 1. The mid-gut polyhedroses was induced by some artificial treatments, of which the most effective one was low temperature treatment (at 5℃ for 24 hours) at the 5th instar before first feeding. 2. Author found a few infected silkworms which were reared by a farmer in fall in 1964. It was supposed that the induction of this disease was due to the cumulative effects of the bad conditions on the silkworms. Especially the great cause of this disease depended on the quality of the mulberry leaves.