• 한국의학물리학회:학술대회논문집
• /
• 한국의학물리학회 2002년도 Proceedings
• /
• pp.121-122
• /
• 2002

The main principle of radiation therapy is to deliver optimum dose to tumor to increase tumor cure probability while minimizing dose to critical normal structure to reduce complications. RTP system is required for proper dose plan in radiation therapy treatment. The main goal of this research is to develop dose model for photon, electron, and brachytherapy, and to display dose distribution on patient images with optimum process. The main items developed in this research includes: (l) user requirements and quality control; analysis of user requirement in RTP, networking between RTP and relevant equipment, quality control using phantom for clinical application (2) dose model in RTP; photon, electron, brachytherapy, modifying dose model (3) image processing and 3D visualization; 2D image processing, auto contouring, image reconstruction, 3D visualization (4) object modeling and graphic user interface; development of total software structure, step-by-step planning procedure, window design and user-interface. Our final product show strong capability for routine and advance RTP planning.

• 대한안전경영과학회지
• /
• 제1권1호
• /
• pp.101-110
• /
• 1999

QFD is a market driven design and development methodology for products and services to meet or exceed customer's needs and expectations, This method enables to specify clearly the customer's needs and then evaluate the product capability in terms of its impact on meeting those needs. Process of satisfying customers begins with effectively soliciting their different needs and wants which may be non-technical and imprecise in nature. Although the HoQ is a comprehensive tool for showing the relationships between attributes, it lacks the flexibility to deal with the inherent inexactness and vagueness in the voice of customer. In this paper, fuzzy theory is introduced to overcome this limitation. Qualitative customer requirements are interpreted quantitative data through fuzzy inference procedure, and then target value is determined.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 2005년도 춘계학술대회 논문집
• /
• pp.278-281
• /
• 2005

Today, manufacturing capability at the micro or nano scale production field is requested strongly in view of parts and product miniaturization. Miniaturized parts and products will introduce lots of benefits in terms of high precision functionality and low energy consumption. This paper presents the results of micro milling machine tool development for micro machining process. Finite element analysis has been performed to know the relationship between design dimensional variables and structural stiffness in terms of static, dynamic, thermal aspects. Performance evaluation through machining has been tested and discussed for achievable machining characteristics.

• 한국생산제조학회지
• /
• 제18권6호
• /
• pp.681-689
• /
• 2009

Disk grinding was often applied to deburring process in order to enhance the final product quality. Inherent chamfering capability of the flexible disk grinding process in the early stage was analyzed with respect to various process parameters including workpiece length, wheel speed, depth of cut and feed. Initial chamfered edge defined as arc zone was characterized with local radius of curvature. Averaged radius and arc zone ratio was well evaluated using neural network system. Additional neural network analysis adding workpiece length showed enhance performance in predicting arc zone ratio and curvature radius with reduced error rate. A process condition design parameter was estimated using remaining input and output parameters with the prediction error rate lower than 2.0% depending on the relevant input parameter combination and neural network structure composition.

• 청정기술
• /
• 제24권1호
• /
• pp.15-20
• /
• 2018

Hexafluoropropyleneoxide ($C_3F_6O$, HFPO) is highly expensive and it may be used as a raw material for the synthesis of various fluorine based compounds. Currently, extractive distillation method has gained considerable attention to collect the HFPO from a mixture of HFPO / hexafluoropropylene ($C_3F_6$, HFP). Optimized operating conditions are studied using a theoretical method for the extraction process. Among available solvents for the purification process, the use of 1,1-dichloro-1-fluoroethane exhibits a high purity of HFPO as a top product and minimize the required heat duty. Since the boiling point of the solvent increases as the pressure in the column increases, the enhanced extractive capability of the solvent led to the high purity of HFPO at the high pressure.

• 소성∙가공
• /
• 제12권5호
• /
• pp.421-432
• /
• 2003

The dies & molds are a very economical production tool and a high value-added product because of its mass production capability compared to other production methods. Due to the very stiff international competitiveness, the industries meet many obstacles. For the promotion of the industry, the status and the international trends of the industry are measured. The vision and strategy are driven. In Korea, large portion of dies and molds are still low value-added and make large number of tools. In order to advance this industry to the high-tech area and gain competitiveness in the global marketplaces, effective means of resource investment and strategy should be properly provided.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제13권1호
• /
• pp.8-14
• /
• 2013

A low density parity check (LDPC) decoder provides a most powerful error control capability for mobile communication devices and storage systems, due to its performance being close to Shannon's limit. In this paper, we introduce an efficient overlapped LDPC decoding algorithm using a upper dual-diagonal parity check matrix structure. By means of this algorithm, the LDPC decoder can concurrently execute parts of the check node update and variable node update in the sum-product algorithm. In this way, we can reduce the number of clock cycles per iteration as well as reduce the total latency. The proposed decoding structure offers a very simple control and is very flexible in terms of the variable bit length and variable code rate. The experiment results show that the proposed decoder can complete the decoding of codewords within 70% of the number of clock cycles required for a conventional non-overlapped decoder. The proposed design also reduces the power consumption by 33% when compared to the non-overlapped design.

• 한국항공운항학회지
• /
• 제21권3호
• /
• pp.9-14
• /
• 2013

Continuous airworthiness system is comprised of regulations and procedures to assure the safety and reliability through the total stage of development, certification and operation of aircraft. The purpose of this system is not only to provide the guidelines that should be kept by manufacturers and operators, but also to evaluate the maintenance capability in every activity of safety related procedures. During the development process of the mid and large size aircraft, operational experience should be reflected systematically for a safer and more reliable product by using the meaningful data base from operation. The relationship of safety roles between manufacturer and operator is mutually complementary, and the roles of each function have an influence to the next step. Overall structure of the procedure contains the concept of continuous analysis and feedback to achieve highest degree of safety and reliability during the entire life of aircraft. Finally, this paper describes how the feedback is made and used for aircraft design from operational experience under the continuous analysis and surveillance system.

• 정보처리학회논문지D
• /
• 제19D권1호
• /
• pp.29-38
• /
• 2012

국내 최초로 소프트웨어 글로벌화 품질관리(Globalization Quality Management, GQM) 프레임워크를 설계하고 실제 산업 현장에 적용하였다. GQM은 글로벌화 경험이 미약한 국내 소프트웨어 업체를 대상으로 글로벌화 기술 적용 결과를 국제 표준에 적합한 수준으로 끌어올리기위한 지원 및 점검을 위한 도구이다. 소프트웨어 개발 주기에 따른 체크포인트 기반의 품질관리 프로세스, 글로벌화 기술지원 모델 및 품질점검 모델로 구성된 GQM은 폭포수를 비롯한 계획주도방법론과 애자일을 포함한 반복점증방법론을 모두 지원한다. GQM에 기반하여 31개 소프트웨어 업체를 대상으로 글로벌화 수준진단을 수행하고 5점 척도로 평가한 결과, 글로벌화 역량이 2.47, 글로벌화 준비도가 2.55로 나타났다. 또한, 글로벌화 기술 도입을 위한 선결요건은 국제화 기술을 반영한 제품 설계(32.9%)와 글로벌 요구사항 분석(28%)으로 조사되었다.

• 정보화연구
• /
• 제9권3호
• /
• pp.275-285
• /
• 2012

모의기반획득 과정에서 물리적으로 분산되어 있는 기관들 간의 상호운용성을 향상 시키기 위해서는 데이터 교환 서식(DIF: Data Interchange Format)을 필요로 한다. 데이터 교환서식은 분산제품 기술서(DPD: Distributed Product Description)의 템플릿 역할을 하며, 분산제품 기술서의 각종 정보 및 M&S 자원을 입력 및 출력하게 함으로써 별도의 변환 과정 없이 정보를 바로 이용할 수 있게 하는 장점이 있다. 이러한 특징은 모의기반획득을 지원하는 통합협업환경이 상호운용성을 제공하기 위하여 반드시 필요하다. 본 논문에서는 모의기반획득의 제반 절차 단계 중에서 설계 및 제조와 관련된 형상 데이터를 대상으로 데이터 교환서식 개발을 위한 프레임워크 및 단계별 산출물을 제안하고, 이를 바탕으로 데이터 교환서식 모델 설계에 대한 연구를 수행하였다. 또한 제안된 데이터 교환서식 모델을 기반으로 XML 기반의 데이터 교환서식 모델을 구현하고, 사례를 통하여 데이터 교환서식을 이용한 데이터 변환을 시연함으로써 제안된 데이터 교환서식의 성능을 검증하였다.