• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.524-524
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• 2000

We have been developing a method to build one-step-ahead prediction models for time series using genetic programming (GP). Our model building method consists of two stages. In the first stage, functional forms of the models are inherited from their parent models through crossover operation of GP. In the second stage, the parameters of the newborn model arc optimized based on an iterative method just like the back propagation. The proposed method has been applied to various kinds of time series problems. An application to the seismic ground motion was presented in the KACC'99, and since then the method has been improved in many aspects, for example, additions of new node functions, improvements of the node functions, and new exploitations of many kinds of mutation operators. The new ideas and trials enhance the ability to generate effective and complicated models and reduce CPU time. Today, we will present a couple of financial applications, espc:cially focusing on gold price prediction in Tokyo market.

• 소성∙가공
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• 제8권6호
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• pp.541-553
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• 1999

Cold forging is a special type of forging process in which metal is forced to flow plastically under compressive force into a variety of shapes in room temperature. Gear blank, which is produced by cold forging, is concerned with the production method of transmission gear. Based on the results of simulation of the current four-stage process, the gear blank forging process for improving the conventional process sequence is designed. The rigid plastic finite element analysis for improving the conventional process. The new process consists of three stage operations with one annealing treatment after first operation. Based on the results of simulation of the proposed process, a required equipment could be selected. The new designed process appears to be more economical in producing the gear blank.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제5권3호
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• pp.274-279
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• 2005

For high-speed fuzzy control systems, an important problem is the improvement of speed for the fuzzy inference, particularly in the consequent part and the defuzzification stage. This paper introduces an algorithm to map real values of the fuzzy membership functions in the consequent part onto an integer grid, as well as a method of eliminating the unnecessary operations of the zero items in the defuzzification stage, allowing a center of gravity method to be implemented with only integer additions and one integer division. A VHDL implementation of the system is presented. The proposed system shows approximately an order of magnitude increase in speed as compared with conventional methods while introducing only a minimal error and can be used in many fuzzy controller applications.

• Clinical and Experimental Pediatrics
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• 제45권12호
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• pp.1534-1539
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• 2002

목 적 : Wilms 종양은 진행된 경우에서도 수술, 방사선 치료, 항암화학요법의 병합요법으로 치료 성적이 우수하지만 방사선 치료로 인한 후기 합병증이 문제가 될 수 있다. 본 연구에서는 진행된 Wilms 종양(병기 3기, 4기)에서 수술 전 화학요법을 시행하여 종양의 완전 절제율을 높임으로써 방사선 치료를 생략하고자 하였다. 방 법 : 저자들은 1998년 12월부터 2002년 7월까지 삼성서울병원에서 Wilms 종양으로 치료를 시작한 환자 중 침 생검 후 수술 전 화학요법을 시행하였던 환자를 대상으로 하였다. 진단 시 3기, 4기의 환자에서 침 생검이 가능한 경우 수술 전 항암화학요법(vincristine, adriamycin, dactinomycin)을 12주간 시행 후 종양의 크기가 감소하면 종양 절제술을 시행하였고 완전 절제가 된 경우 방사선 치료를 생략하고 수술 후 화학요법(vincristine, dactinomycin${\pm}$adriamycin)을 시행하였다. 침 생검이 기술적으로 어렵거나 위험하다고 생각되었던 경우에는 먼저 수술적으로 종양을 절제하고 방사선 치료와 화학요법을 시행하였다. 결 과 : 연구기간 중 삼성서울병원에서 치료를 시작한 17례의 Wilms 종양 중 3기, 4기는 12례였고 이중 2례에서는 침생검이 불가능하여 먼저 수술적으로 종양을 절제하였고 침생검이 가능하였던 경우는 10례였다. 이들의 진단 시 정중 연령은 21개월(5개월-103개월)이었고, 진단 후 정중 추적기간은 31개월(9개월-44개월)이었다. 수술 전 화학요법을 시행한 10례 중 2례를 제외한 8례에서 수술시 병기가 1기로 하향화되었으며, 수술시 병기가 2기였던 1례와 함께 총 9례에서 종양의 완전절제가 가능했고 방사선 치료도 생략할 수 있었다. 이들 중 4례에서는 adriamycin도 치료에서 제외하였다. 종양의 완전 절제에 실패한 1례는 결국 사망하였고, 1례는 재발하였으나 강화된 항암화학요법과 수술로 다시 관해에 도달하여 현재 10례 중 9례가 무병 생존 중이다. 결 론 : 진행된 Wilms 종양에서 수술 전 화학요법을 시행하여 종양의 완전 절제율을 높이고 방사선 치료를 생략할 수 있었으며, 일부 환자에서는 수술 후 화학요법의 강도를 감소시킬 수 있었다. 향후 생존율의 저하 없이 후기 합병증을 줄일 수 있을 지에 대한 연구가 필요할 것으로 사료된다.

• Advances in pediatric surgery
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• 제18권2호
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• pp.75-82
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• 2012

In one-stage transanal endorectal pull-through operation (TERPT) for Hirschsprung disease, preoperative evaluation by contrast enema (CE) is important tool in aspect of planning of surgical procedure as well as diagnosis. This study was to evaluate the significance of CE for identifying the extent of aganglionic bowel. A retrospective analysis was performed in 40 patients who underwent TERPT between 2003 and 2011. The authors reviewed the CE studies and their correlation with pathologic extent of aganglionosis. Total 66 contrast enemas were performed in 40 patients. Twenty patients underwent single CE, but 20 patients required multiple CEs. In single CE group, 17 had clear radiographic transition zone, but 3 had less definite transition zone. In multiple CE group, 17 patients who had equivocal finding in first or second CE had definite radiographic transition zone, but 3 patients of this group had less definite radiographic transition zones. Overall, 34 patients (85%)had clear radiographic transition zone by single or repeated CE. One (2.9%) out of 34 patients with clear radiographic transition zone had discordance between radiographic and pathologic transition zone. In contrast 4 (66.7%) out of 6 patients with equivocal radiographic transition zone had discordance between radiographic and pathologic transition zone. Observation of clear radiographic transition zone is important in preparation of TERPT, and repeated CE is helpful to reduce the discordance between radiographic and pathologic transition zone. Awareness of the possibility of discordance is also important if radiographic transitional zone is not clear.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 제5회 박판성형 SYMPOSIUM
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• pp.68-71
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• 2006

Traditional section-based method develops blank along section planes and find trimming line by generating loop of end points. This method suffers from inaccurate results for regions with out-of-section motion. In this study, new fast method to find feasible trimming line is proposed. One step FEM is used to analyze the flanging and incremental development method is proposed to handle bad-shaped mesh and undercut part. Also in order to remedy mesh distortion during development, energy minimization technique is utilized. The proposed method is verified by shrink/stretch flange forming and successfully applied to the complex industrial applications such as door outer flanging process.

• 대한기관식도과학회지
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• 제3권2호
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• pp.327-331
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• 1997

One of the most difficult airway problems is a subglottic stenosis combined with a tracheal stenosis. Laryngotracheal stenosis has not been completely solved with classic methods like cricotracheal split with autogenous cartilage graft, thyrotracheal anastomosis, and free hyoid or hyoid-sternohyoid myo-osseous flap reconstruction. A 28-near-old male patient who had had laryngotracheal stenosis was successfully treated by laryngotracheal reconstruction using vascularized clavicle. This method has a several advantages: the vascularized clavicle harvesting in the same operative fields, one stage operation, less restenosis due to plentyful blood supply, md prevention of airway collapse due to a clavicle provided framework. It is too early to make a definite conclusion, but the authors suggested that this method could become one of the most effective methods of laryngotracheal stenosis.

• Journal of Korean Neurosurgical Society
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• 제37권5호
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• pp.375-379
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• 2005

Rarely, rupture of a cerebral aneurysm causes an acute subdural hematoma(SDH) in addition to subarachnoid hemorrhage(SAH). We report clinical and radiological characteristics of five cases, as well as potential pitfalls in the diagnosis and the treatment of this life-threatening condition. The patients ranged in age from 42 to 76 years. The Hunt-Hess grade on admission was grade III in one patient, grade IV in two, and grade V in two. All five patients un-derwent one-stage operation (both SDH evacuation and clipping of the aneurysm). The outcome was good recovery in two patients, persistent vegetative state in two, and death in one. Patients with a good outcome had a better Hunt-Hess grade on admission, with less amount of SDH.

• 산업공학
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• 제25권3호
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• pp.338-346
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• 2012

Regarding the green environment, it is important to boost the spread of environmentally friendly vending machines and to operate the vehicles for their inventory replenishments while minimizing emissions of greenhouse gases. In general, the vending machine management company lacks capability to operate the supply chain effectively in an integrated way under the dynamic, complex, and stochastic environment. This paper presents a decision support system, termed DSSVM, for the operations of the general and smart vending machine supply chains with stock-out-based, one stage item substitution in a green logistics environment. The DSSVM supports the estimation of item demand and substitution probabilities, determination of operation parameters, supply chain analysis, what-if analysis, and $CO_2$ analysis for which various analytical models are employed.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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• pp.763-768
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• 1994

A hierarchical Petri- net is utilized in supervising an automated vehicle system, The supervisory system is supported by computer networking in order to facilitate necessary processing, and consists of control flow level and computer allocation level so that a designer and an operator can easily build and/or access to each level. There are two modes of utilizing Petri net here in this paper. One is to employ it in designing the control system, in order to optimally allocate computers in every stage of processing. The other is for supervision of the system in operation, in order for the operator to be in a easy-to-comprehend environment of operation. The effect of these two modes of utilizing Petri net is examined.