• Journal of Chest Surgery
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• 제17권4호
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• pp.740-746
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• 1984

Mucoepidermoid tumor arising from the bronchial tree as one of the bronchial adenoma is a extremely rare in incidence. And its clinical and histopathologic behavior has been reported as varying degree of benign to extremely malignant. Because symptoms are usually related to the bronchial obstruction or obstructive pneumonitis followed by endobronchial growth of tumor, frequently error is made in diagnosis of this tumor as entity of obstructive lung disease. We present a case of mucoepidermoid tumor with review of relevant literatures arising from the right middle lobe bronchus extending to intermediate bronchus in 47 years old housewife and was surgically removed by middle and lower Iobectomy.

• Journal of Chest Surgery
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• 제26권5호
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• pp.417-421
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• 1993

Congenital diaphragmatic hernia through Bochdalek foramen, posterolateral diaphragmatic hernia, is the result of a congenital malformation of the posterolateral region of the diaphragm. Bochdalek hernia is the most common type of congenital diaphragmatic hernia, but it is a extremely rare anomaly which is detected in adulthood because it has severe cardiopulmonary and gastrointestinal symptoms after birth immediately.We experienced two cases of Bochdalek hernia which were detected in adulthood. Among them, one was a 43 years old man who was treated with simple closure in left Bochdalek hernia and the other was 41 years old woman who was treated with patch closure using silastic sheet in right Bochdalek hernia. Their postoperative courses were uneventiful. So we report two cases of rare Bochdalek hernia which was detected in adulthood with review of literatures.

• 한국경영과학회지
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• 제24권3호
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• pp.13-26
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• 1999

Recently, information technology and information system(IS) are rapidly diffused throughout the world. In the global competitive environment, the success of IS becomes the important one among the critical success factors(CSF) of the firm. For achieving it, the firm must continually involve itself in the quality evaluation and improvement of IS. The quality concept was changed into the customer-oriented quality one. There is no exception to the quality of IS. In the past, IS quality was determined by the IS developer or IS department offering service. Now it is evaluated by the user of IS service, and then the customer-oriented user satisfaction becomes an important issue. The purpose of this study is to develope the total quality evaluation model of IS through TQM approach. First, all success factors of the domestic IS are extracted from the foreign and domestic literatures of IS success factors contained the technical and behavioral aspects. And the extracted factors are classified with evaluation levels for quality evaluation and developed into a total quality evaluation model. Finally the model usefulness is analyzed.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1996년도 추계학술대회발표논문집; 고려대학교, 서울; 26 Oct. 1996
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• pp.135-138
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• 1996

In solving the Travel Salesman Problem(TSP), we easily reach local optimal solutions with the existing methods such as TWO-OPT, THREE-OPT, and Lin-Kernighen. Tabu search, as a meta heuristic, is a good mechanism to get an optimal or a near optimal solution escaping from the local optimal. By utilizing AI concepts, tabu search continues to search for improved solutions. In this study, we focus on developing a new neighborhood structure that maintains the feasibility of the tours created by exchange operations in TSP. Intelligent methods are discussed, which keeps feasible tour routes even after exchanging several edges continuously. An extended tabu search model, performing cycle detection and diversification with memory structure, is applied to TSP. The model uses effectively the information gathered during the search process. Finally, the results of tabu search and simulated annealing are compared based on the TSP problems in the prior literatures.

• 한국경영과학회지
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• 제12권1호
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• pp.175-175
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• 1987

Business reengineering (BR) is an emerging idea that attempts to restructure inefficient, current business processes through redesigning jobs and exploiting new information technology (IT), and helps achieving significant improvements in white-collar productivity and returns of IT investment. This research analyzed order-taking and purchasing processes of a company (a coil distributor) using BR concepts, models and principles. We also made proposals for reengineering the present business processes. For this, BR literatures were reviewed to derive BR models and principles to be used for analyses. We applied these ideas to six(6) types of order-taking and purchasing processes of Company T. For each type, current processes, BR analyses, and proposals for BR were described. Finally, findings were summarized and discussed.

• 경영과학
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• 제32권4호
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• pp.81-96
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• 2015

This paper models knowledge diffusion on an inter-organizational network. Based on literatures related to knowledge diffusion, the model considers critical factors that affect diffusion behavior including nodal property, relational property, and environmental property. We examine the relationships among network structure, knowledge search, and diffusion performance. Through a massive simulation runs based on the agent-based model, we find that the average path length of a network decreases a firm's cumulative knowledge stock, whereas the clustering coefficient of a firm has no significant relationship with the firm's knowledge. We also find that there is an interaction effect of network structure and the range of knowledge search on knowledge diffusion. Specifically, in a network of a larger average path length (APL) the marginal effect of search conduct is significantly greater than in that of a smaller APL.

• Journal of Pharmaceutical Investigation
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• 제1권1호
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• pp.62-69
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• 1971

The method of assessing drug availability has been the subject of much concern and the equation is presented to estimate the drug availability of dosage forms and to calculate the desirable rates of drug absorption in a model. $Xmax/X_0=(k_1/k_2)^{{\frac{1}{1-^-k_1/k_2}}}$ To facilitate the calculations involved in the equation, a program in Fortran with Format was used in the IBM 1130 digital computer system. Using availability, $Xmax/X_0$, and the given rates of elimination from the blood, the desirable rates of drug absorption in the model were calculated and shown in detail. Applicabiliy of the equation to estimate the drug availability of dosage forms in the model was demonstrated with different sets of data from the literatures.

• 한국압력기기공학회 논문집
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• 제9권1호
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• pp.70-76
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• 2013

Several finite element models for the leak-before-break (LBB) assessment of overlay dissimilar metal weldment were constructed and analyzed to develop a simple finite element modeling method. The J-integral, crack opening displacement (COD) and J-integral distribution along the crack front in thickness direction due to the applied moment were obtained from the analysis results of the constructed finite element models, and studied compared to the previous literatures. It is concluded that the modeling with base material only is simple and produces a slightly conservative results compared to the complex modeling composed with weld metal and base metal in the calculation of J-integrals and COD values which are used for the calculation of fracture toughness and postulated leakage crack length respectively.

• 한국자동차공학회논문집
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• 제12권3호
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• pp.177-183
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• 2004

The out-of-positioned small female drivers are most likely to be injured during airbag deployment due to their stature and proximity to the steering wheel and airbag module. In order to investigate the injury mechanisms, some experimental studies with Hybrid III 5% female dummy and with female cadavers could be found from the open literatures. However, the given information from those experimental studies is quite limited to the standard conditions and might not be enough to estimate the airbag inflation aggressiveness regarding on the occupant responses and injury. In this study, a finite element analysis has been performed in order to investigate the airbag-induced injuries. A finite element 5% female human model in anatomical details has been developed. The validation results of the model are also introduced in this paper.

• 한국자동차공학회논문집
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• 제8권6호
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• pp.122-129
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• 2000

This paper describes a hybrid dynamic system(HDS) modeling method and result for the drivertrain of a parallel hybrid electric vehicle(PHEV) which consists of a gasoline engine, an electric machine, and a continuous variable transmission (CVT) and proposes a drivetrain control system. The control system has an engine controller, a motor controller, a CVT controller and a supervisory controller for the coordination of all system. The controller keep the speed of engine wheel and the output torque within the optimal operation range based on the experimental data. We also developed a MATLAB/SIMULINK program for the performance simulation of PHEV drivetrain model and controllers and compared the simulation result with the experiment result in the recent literatures.