家兎에서 局所貧血이 筋肉變化에 미치는 影響에 關한 實驗的 硏究

金昌洙,李弘鍵 고려대학교 의과대학 1982 고려대 의대 잡지 Vol.19 No.1

Early detection of muscular changes in ischemia should be the utmost important and urgent problem in management and recovery of the muscles before irreversible picture developes. In the relevant literatures, many authors have studied upon histological changes of muscles. in ischemia employing various staining methods, such as hematoxylin and eosin (H&E), van Gieson etc., and reported that the earliest possible time fot detection of morphological changer in muscles were 3 to 4 hours after ischemia took place. Other methods, such as measurement of pressure in the muscular tissue with wick catheter, never conduction time, electromyography, tissue fluid analysis, enzyme study of serum, lactic acid study, ^(99m)Tc stannous pyrophosphate, electronmicroscopic study did not provide valuable early detection of muscular changes in ischemia. The author has undertaken an experimental study upon morphological changes of the muscles, after ischsmia were produced artificially with ligation of vessels and using tourniquet, and tried to detect early changes in the ischemic muscle by histochemical staining method developed by Lie et al., hematoxylin basic fuchsinpicric acid (HBFP) staining method. Twenty rabbits, weighing 2,000-2,500gm were divided into two groups. In group 1, tourniquet was applied on the proximal thigh, and in group 2, the unilateral common iliac artery and vein were ligated. In each group, muscle biopsies were carried out of the belly of the anterior tibial muscles in 10 minutes, 30 minutes, 1 hour, 2 fours, 3 hours, 6 hours, 24 hours, and 48 hours, respectively, while the applied tourniquet or ligation was released 6hours after application. The biopsied samples were fixed in formalin and stained with H&E and HBFP stain for microscopic evaluation of muscle changes. The results are as follows: 1. In group 1, the earliest evidence of muscular degeneration were detected by HBFP staining-method as early as 30 minutes after application of tourniquet, whereas it was required at least 3 hours to detect such change by H&E staining method. 2. In group 2, the earliest evidence of muscular degeneration were detected by HBFP staining method as early as 10 minutes after ligation of the vessels, whereas it was required atleast 2 hour to detect such change by H&E staining method. 3. In group 2, the minimal elapse of the time to detect muscular necrosis after ligation of the vessel was 2 hours by HBFP staining method whereas it took 24 hours by H&E staining method. 4. The above findings suggest that the HBFP staining is the most practical method to detect not omly early degenerative change of muscle but the evaluation of the extent of the changes due to ischemia.

APPLICATION OF TRAVELING SALESMAN PROBLEM(TSP) FOR DECISION OF OPTIMAL PRODUCTION SEQUENCE

Chang, Kun Soo,Yeo, Yeong Koo,Chang, Jin Yang,Kim, Kil Su,Jeong, Eun Young,Oh, Sea Cheon 한국화학공학회 1997 Korean Journal of Chemical Engineering Vol.14 No.5

In the present study a reliable and structural decision system for production sequence of polymeric products is developed. Minimization of the amount of off-specs are the main objective in the decision of production sequence to maximize profit. Off-specs are generated when the production sequence of polymeric products is changed. The amount of off-specs depends on changes of product grades. In the present study we applied the traveling salesman problem (TSP) to achieve optimal decision of production sequence. To solve the optimal decision problem formulated by TSP, we employed three different approaches such as Branch and Bound (B&B) method. Dynamic Programming (DP) method and Hopfield Neural Network (HNN) method. Production sequences computed based on the actual plant off-spec data were compared with the sequences employed in the actual plant operation. From the comparison the decision method proposed in the present study showed increased profits and reduced off-specs.

콤바인 HST 전자제어시스템 개발

서신원(Sin-Won Seo),허윤근(Yun-Kun Huh),이제용(Je-Yong Lee),이창규(Chang-Kyu Lee),배근수(Keun-Soo Bae) 충남대학교 농업과학연구소 2011 농업과학연구 Vol.38 No.1

I/An electro-hydraulic transmission having advantages of convenience, safety, simple linking and high power, and an electronic control system were designed and fabricated. In this study, characteristics of the control system were investigated through outdoor tests for evaluation of installation of the system on a combine. Major findings were as followings. 1. Experiment for performance evaluation of the control system was conducted on concrete road. With steering lever in neutral position, driving HST swash plate and left/right wheel speed increased in proportion to driving lever angle. In case of steering control, steering swash plate angle changed in proportion to steering lever angle. This should cause increase in outer wheel speed, but it was observed that HST swash plate was controlled toward neutral to maintain the speed before steering. As a result, speed before steering was maintained despite the change in outer wheel speed by steering HST swash plate angle change. 2. It was observed that the HST system enabled steering with outer wheel maintained at constant speeds while inner wheel speed decreased, which was more stable than conventional mechanical links. In addition, for the selected 5 criteria, experiment showed satisfactory results and it was judged that installation on real vehicle would be feasible. 3. The control system showed response property of appropriate forward/reverse movement and lift/right steering, without causing any problems during experiment on concrete. Result of response property experiment on field operation also showed appropriate control over forward/reverse movement and left/right steering

Short Communication : Application of Traveling Salesman Problem (TSP) For Decision of Optimal Production Sequence

( Eun Young Jeong ),( Sea Cheon Oh ),( Yeong Koo Yeo ),( Kun Soo Chang ),( Jin Yang Chang ),( Kil Su Kim ) 한국화학공학회 1997 Korean Journal of Chemical Engineering Vol.14 No.5

In the present study a reliable and structural decision system for production sequence of polymeric products is developed. Minimization of the amount of off-specs are the main objective in the decision of production sequence to maximize profit. Off-specs are generated when the production sequence of polymeric products is changed. The amount of off-specs depends on changes of product grades. In the present study we applied the traveling salesman problem (TSP) to achieve optimal decision of production sequence. To solve the optimal decision problem formulated by TSP, we employed three different approaches such as Branch and Bound (B&B) method. Dynamic Programming (DP) method and Hopfield Neural Network (HNN) method. Production sequences computed based on the actual plant off-spec data were compared with the sequences employed in the actual plant operation. From the comparison the decision method proposed in the present study showed increased profits and reduced off-specs.

球狀黑鉛鑄鐵의 鹽浴窒化

張忠根,金水泳,李相益 충남대학교 자연과학연구소 1977 學術硏究誌 Vol.4 No.1

Liquid nitriding is being is used for machine parts to improve fatigue strength and resistance to wear and seizure in spheroidal graphite cist iron. The difference in matrixes with as cast, pesrlite or ferritic structure in the iron has an important effect on nitriding. in the present work, spheroidal graphite cast irons with different matrixes nitrided by the tufftride process at 570 C for 1-6 hrs for a bask study on the nitriding of spheroids1 graphite castiron. The relationship between maximun hardness and nitriding time can be obtained as follows. In ferritic matris, hardness of matrix increased from 250Hv for 6hrs of nitriding time. In pearlite matrix, hardness of matrix increased from 390Hv to 560Hv. for 6 hrs of nitrding time.

철-질소 2원계에서 r´-phase의성장에 관한 연구(Ⅱ)

장충근,김수영 충남대학교 자연과학연구소 1983 忠南科學硏究誌 Vol.10 No.2

In order to observe the effect of adding silicon and carbon in to the prepared Fe-Si and Fe-C alloyed specimens which were nitrided by using a nitrogen gas agent in the temperature range of 650-850℃. The effect of silicon and carbon on the frequency factor, activation energy and surface hardness of the specimens were also investigated. The relationships between the activation energy and the amount of silicon and carbon were obtained as Q(msi)=27.2 exp 23.92(msi) Kcal/mole Q(mc)=27.2 exp 30.70(mc) Kcal/mole The surface hardness of the specimens increased sharply by nitriding, but it decreased slightly when nitrided for a considerably long time, while the internal hardness increased.

개 시상하부의 Neuropeptides에 대한 면역조직화학적 연구

장인엽,정윤영,김종중,문정석,김준수,모근석,임용,유호진 朝鮮大學校 附設 醫學硏究所 1996 The Medical Journal of Chosun University Vol.21 No.1

The distribution and localization of somatostatin(SOM), neuropeptide Y(NPY), vasopressin(VP), and oxytocin(OT) were studied with a immunohistochemical technique in the canine hypothalamus. The SOM-immunoreactive perikarya were concentrated in the anterior periventricular and the arcuate nuclei. Immunoreactive terminals were observed in the arcuate, the ventromedial hypothalamic, the suprachismatic nuclei and the external layer of the median emmence. A great number of NPY-immunoreactive cell bodies were found in the arcuate nucleus and NPY fibers were located throughout the hypothalamus with the highest concentration especially in the paraventricular (PVN) and the acuate nuclei. Moderately or densely stained fibers were also observed in the median eminence, the suprachiasmatic. the periventricular, the ventromedial hypothalamic, the dorsomedial hypothalamic and the medial preoptic nuclei, and the stria terminalis. Both VP-and OT-containing perikarya were found mainly in the PVN and supraoptic nucleus(SON). but a few were seen in the perifornical area, the lateral hypothalamus, the dorsal hypothalamic and the periventricular nucleus. The fibers originated from the PVN were projected to the SON via ventral or dorsal area of the fornix.

평행선 공리의 독립성

장건수 연세대학교 교육대학원 1982 연세교육과학 Vol.21 No.-

Euclid's axiom of parallels looks more like a theorem than an axiom. It was suspected for a long time that the axiom of parallels could be proved from the other axioms of Euclidean geometry. The question was settled first around 1830 by three mathematicians who worked independently of each other, the German Gauss, the Hungarian Bolyai and the Russian Lobachewski. Each of them constructed a geometry, logically possessing equality of rights with Euclidean geometry, where the axiom of parallels was replaced by the following axiom: Suppose that s is a straight line and that A is a point not lying on s. Then there exists more than one straight line that passes through A and is parallel to s. The resulting geometry is called hyperbolic geometry. This geometry is a non-Euclidean geometry. Around 1870 the French mathematician Poincare´ constructed a model for hyperbolic geometry within Euclidean geometry. It follows that if hyperbolic geometry will ever lead to a contradiction, then Euclidean geometry also will. In this paper we shall study a model for hyperbolic geometry that is closely related to Poincare´'s model.

Wiener측도 공간

장건수 연세대학교 교육대학원 1981 연세교육과학 Vol.18 No.-

The most interesting measure on a function space is Wiener measure. It was introduced by Nobert Wiener by using Brownian motion. Brownian motion was observed first by Robert Brown in 1827. In 1905, a theoretical and quantitative approach to Brownian motion was given for the first time by Albert Einstein. In this paper we introduce the concepts of Riemann integral and Lebesgue integral and then construct Wiener measure space. We examine the relations between Letesgue measure and Wiener measure. Finally the scale-invariant measurability in Wiener Space which was introduced recently by G.W. Johnson and D.L. Skoug will be discussed

FC-25계 회주철의 Boro-Nitriding 복합 표면처리에 따른 표면특성과 고온산화거동에 관한 연구

허인창,손근수,윤재홍,조동율,박봉규,김현수,김인수 대한금속재료학회 2005 대한금속·재료학회지 Vol.43 No.2

Surface properties and oxidation behavior were studied for FC-25 gray cast iron (GCI), ion nitrided CCI (N CCI), powder boronized CCI (B GCI) and powder boronized N CCI (B-N GCI). A boride (Fe2B and FeB) layer with a tooth shape was formed by boronizing GCI at 650℃. The thickness and hardness of the layer were proportional to boronizing temperature and time. The hardness was decreased as the depth of the boronized layer increased. The activation energy for boride formation was about 74 kJ/mol. The thickness of the graphite layer formed by boronizing was increased by increasing temperature and time. A silicon layer insoluble to borides accumulated beneath the boride layer. The major phases were Fe4N, Fe3N and FeN in the nitride layer formed by ion nitriding. The thickness and hardness of the layer increased with increasing nitriding temperature and time under the Fe4N decomposition temperature of 680℃. The hardness was maximum at the surface and decreased with increasing nitrided depth on B-N GCI at 700℃, above the Fe4N decomposition temperature. Hardness of B-N GCI at the layer depth of 10 μm was 1000 Hv, which was lower than that of the B GCI at the same condition. Also the layer thickness was 50 gm; 10 μm deeper than that of B GCI. The reason was that the nitrogen gas given off by the decomposition made the layer porous and facilitated the diffusion of oxygen and other reactants. The samples were oxidated at 800℃ for 48hrs under atmospheric air. Oxidation rate was in decreasing order of N GCI, GCI, B GCI and B-N GCI. Oxidation rates were greatly influenced by the diffusion of nitrogen gas formed by Fe4N decomposition over the decomposition temperature of 680℃ and the oxidation barrier of the less corrosive boride layer. (Received October 29, 2004)