STD 61종 금형강의 이온질화처리에 관한 연구(Ⅰ)

안병만,김용길,차병묵,피윤섭,윤재홍,김진관 國立 昌原大學校 産業技術硏究所 1994 産技硏論文集 Vol.8 No.-

STD61종 열간금형강의 수명향상을 위하여 ion nitriding처리를 실시하였다. 이온질화전의 모재의 열처리시에는 1030˚C에서 quenching한 후 530˚C에서 2시간 tempering했을 때 Hv=600의 높은 경도값을 나타내었다. 580˚C, 600˚C에서 2시간 tempering했을 때는 각각 Hv=500, Hv=400으로 경도값이 오히려 감소했다. 이온질화 처리시에는 처리시간이 길고 N₂와 Ar첨가유량이 많을 수록 깊은 화합물층과 확산층을 얻었다. 그리고 각 처리조건에서 안정된 Hv=1150의 질화물층을 얻을 수 있다. Ion nitriding treatment has been practiced to improve the life of hot die steel of STD61. Before nitriding the parent STD61 tempered at 530˚C, 2hrs after quenching at 1030˚C, It showed the high hardness distribution of Hv=600. The hardness distribution has decreased by Hv=400, Hv=500 when tempered for 2hrs at 580˚C, 600˚C. In the ion nitriding, the more treat-time and the more N₂and Ar flux, the deeper the compounded layer and the diffused layer. The stable hardness, Hv=1150, of nitride layer was obtained at various treatment condition.

조합적 최적화 문제 해결을 위한 신경 회로망 모델 개발

柳秉學,鄭成鐘 全北大學校 1992 論文集 Vol.34 No.-

The Traveling Salesman Problem(TSP) is an important example of combinatorial optimization problem which is characterized by its large number of interacting degree of freedom. A neural network system using parallelism is proper to solve combinatorial optimization problem. In this thesis, We improve Mean Field Annealing(MFA) algorithm and propose a new objective function for solving TSP. Appling the algorithm to TSP of 10 cities, and 15 cities, its result converges in optimal solution or nearly optimal solution.

纖維素 分解酵素 生産性 絲狀菌과 그 酵素活性에 關한 硏究

申炳湜,鄭圭永 건국대학교 1979 論文集 Vol.10 No.1

Total 60 strains were isolated from various sources such as soils, composte, and rottenwood, debris using cellulase screen media from the isolated 60 strains in the first experiments 8 strains were first selected text as good ones and identified, cellulase activities were tested The results of these studies are as follows; 1.Identified of 8 strains SK -17 ; SO-2, SW-1 ; Trichoderma viride ST-1 ; Penicillium sp. SO-9 ; Aspergillus oryzae SW-2 ; Aspergillus niger SO-5 ; Aspergillus ochraceus SBN ; Neuropora sp. 2.The strongest of celluase activity is SW-2, SBN and SO-9. The Mark SBN is the strongest in Carboxy Methyl Cellulose liquefaction and SO-9 is higher activities in cup method reaction. 3.In the test of the 1'eaction time of substrate and enzyme. The enzyme activities are high as prorata of reaction time of 24hr, CMC liquefaction become a half of total substrate. 4.According to cultural periods, enzyme activity is reahced the hight one in the 4 or 5 days cultural time airier the 5 days cultural time period enzyme activities was dwindled. 5.At the volume of CMC liquefaction is much, the index of refraction is high by method of diffrential refractometer. 6.In the teat of variation pH of substrate, good results come out at pH 4.6-5.0 of substrate. The optimum temperature was 45-50℃.

韓國經濟의 不均衡的 所得分配에 관한 硏究

이병용 건국대학교 1985 商經論叢 Vol.- No.20

구리가 랫트 肝臟의 ITO細胞의 微細構造에 미치는 影響

장병준 건국대학교 1991 대학원 학술논문집 Vol.33 No.-

This study was undertaken in order to investigate the effects of copper on the perisinusoidal fat strong cells(Ito cells) in the Sprague-Dawley rat liver. 10mg CuSO_4/Kg body weight was injected into abdominal cavity daily for periods of 6,12,24 days. The morphological changes in the Ito cells were observed with electron microscope and the results were as follows: 1) The number of lipid droplets was decreased and they were atrophied. 2) The cisternae of rough endoplasmic reticulum were dilated and occupied with flocculent materials. 3) The large and small vacuoles were observed on the cytoplasm, but more frequently their arrangement were closely related with space of Disse. 4) The collagen fibrils were increased nearby the space of Disse and plasma membrane. 5) The cristae of mitochondria were arranged irregularly and autophagic vesicles were observed.

分散形 電子交換方式에 관한 硏究

朴炳哲 成均館大學校 1982 論文集 Vol.31 No.-

Usual switching control systems using multi processors have some problems and one of the problems is traffic of inter processors that is competition to common use of Bus. In this paper, processors take not used of Bus, but speed path. In practice, the distribted switching system share functions with a processor and load with processors. The size in this system depend upon a number of subscribers and analyze for assembler.

Coacervation-상분리법으로 만든 Ethyl Cellulose 마이크로캅셀의 Glibenclamide 방출특성 및 수용성 첨가제의 영향

김병조,장정수,이문주,김상헌,최영욱 중앙대학교 약학연구소 1996 약학 논총 Vol.10 No.-

Glibenclamide (GBC) is a well-known antidiabetic agent, which stimulates the secretion of endogenous insulin by pancreatic βcells. However, administration of GBC at a high dose can occasionally induced the fatal hypoglycemia, especially in the patients with impaired liver function. Therefore, in order to develop an oral sustained-release preparation which reduces the side effect, microcapsulation of GBC has been carried out in this experiment. Microcapsules of GBC were prepared by coacervation-phase separation method with ethylcellulose as a wall-forming material in cyclohexane, using polyisobutylene as a coacervation-inducing agent. Different amounts of hydrophilic additives. L-arginine(ARG) and polyethylene glycol 4000 (PEG), were added to the microcapsule wall, in order to alter the porosity of the wall and hence to enhance the release of the core material. The microcapsules prepared were examined for physical properties by scanning electron microscopy (SEM) and particle size analysis. The release of the poorly water-soluble GBC was found to be very slow from the microcapsules and strongly dependent on the core to wall ratio of the microcapsules, but it was accelerated considerably with increasing amount of PEG or ARG. In general, on the basis of dissolution kinetics, GBC releases from microcapsules were followed apparent first-order kinetics, while the dissolution data of GBC powder conformed to Hixon-Crowell's cube root law. Therefore, in conclusion, it might be possible to design the sustained-release formulation by the combination of both GBC powder and microcapsules of different core wall ratio with or without hydrophilic additives.

실시간 물리 시뮬레이션 구현 방안 연구

李奉來,李銀姬 弘益大學校 産業技術硏究所 2005 産業技術 Vol.15 No.-

The real-time simulation means that calculation method of the state expressed an object on real time. The real-time simulation calculates motion of objects on real time using the solutions as the model based physics, equation of motion, differential equation, etc. while the animation makes use of joined stationary image continuously. By the development of technology, the real-time simulation based on physics is being watched with keen interest. This paper makes researches into the technology of physics simulation on game using the real-time simulation based on physics and the mathematical method.

Tufftride處理 後 高周波 硬化處理된 軟鋼의 機械的 性質및 高周波 硬化 特性에 관한 硏究

田炳旭,李相允 東亞大學校 大學院 1984 大學院論文集 Vol.8 No.2

A combined heat treatment of tufftride and induction-hardening treatment for mild steel specimens has been carried out to investigate into the improvement in mechanical properties and some induction-hardening characteristics. The results obtained from this experiment are given below; 1. Optical micrographs have shown to vary as changes in the rate of travel at a given output power during induction-hardening, resulting in the decomposition of compound layer and the formation of the Fe-C-N martensitic structure when the travel rate of 3.1 mm/sec. is maintained. 2. Hardness measurements have revealed that specimens treated at the travel rate of 6.2 mm/sec. show an increase in hardness compared to specimens tufftride-treated due to the fact that the content of solute atom dissolved in ferrite increases during induction-hardening, whereas for travel rates of 4.4 mm/sec. and 3.1 mm/sec. the formation of martensitic structure gives a considerable increase in hardness. 3. It has been found that for a given output power as the rate of travel decreases hardness increases, and that the travel rate of 3.1 mm/sec. shows a great increase in surface hardness and effective hardening depth as compared to the travel rate of 4.4 mm/sec. 4. Specimens tufftrided, induction-hardened, and then tempered have shown a somewhat decrease in hardness and an increase in toughness compared to that obtained before tempering treatment. 5. Tensile test has shown that the tensile strength of mild steel specimens treated by this combined heat treatment increases as tufftride treating time increases and as the rate of travel decreases. 6. It has been shown that for a given rate of travel under the same panel control during induction-hardening the output power increases with increasing the diameter of specimens, and smaller specimens generally shows a higher hardness value.

牧會指導者의 指導力 原泉에 對한 硏究

조병창 聖潔大學校 聖潔神學硏究所 1996 聖潔神學硏究 Vol.1 No.-