• 산업경영시스템학회지
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• 제39권4호
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• pp.1-6
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• 2016

As manufacturing industries become globalized, product design affects every area of organization. The design sets the goals for a number of different departments, so if it fails to effectively communicate these goals, the entire organization is less efficient. In addition, To communicate clearly, the design must represent a product that meets its technical specification. GD&T (Geometric Dimensioning and Tolerancing) is one of the most important factors, which has an effect on efficiency of manufacture system, in designing products. However, most of designers in different industries are prone to ignore the importance of GD&T. To analyse the importance of GD&T compliance with international standards for design drawing, a comparison analysis of the difference between two methods, composite profile control and multiple single segment profile control, is performed on three different cases and suggests how it used to be more suitable. Composite profile tolerance is specified by a dual feature control frame that has one profile symbol specified with two lines of tolerance information. Whereas a multiple single segment profile control is when two or more single segment profile callouts are used to define the location and/or orientation and/or size and/or form of a part feature. In this study, the following results will be provided : a clear definition and an obvious difference of the tolerance zone, datums and datums sequence and minimization of tolerances. On this study, composite profile tolerance and multiple single segment profile tolerance were discussed. Next steps of research will consist on reaching more accurate results for profile control. Further research will be focused on dealing with the remaining 14 symbols of GD&T.

• 한국세라믹학회지
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• 제32권6호
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• pp.659-668
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• 1995

Zirconium carbide was prepared from the mixture of metal zirconium and carbon powders in argon atmosphere by Self-propagating High-temperature Synthesis (SHS) in order to obtain the best carbon source and dilution contents. The most exellent result was obtained in the case that active carbon was added as a starting material, 20~30 wt% dilution content. From thermal profile analysis an apparent activation energy of 118 KJ/mol was calculated. The maximum heating rate achieved during 15 wt% ZrC reaction by product dilution method was approximately 1.54$\times$105 K/s. Coupling this value with the measured wave velocity of 1.026cm/s yielded a maximum thermal gradient fo $1.5\times$105 K/cm. Using the definition of t* and the measured wave velocity, the effective thermal diffusivity, $\alpha$, was calculated to be 0.62$\times$102 $\textrm{cm}^2$/s.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1518-1521
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• 2005

The application of focused ion beam (FIB) technology in micro/nano machining has become increasingly popular. Its usage in micro/nano machining has advantages over contemporary photolithography or other micro/nano machining technologies such as small feature resolution, the ability to process without masks and being accommodating for a variety of materials and geometries This paper focus to apply the sputtering technology accumulated by experiments to 3d structure fabrication with high resolution. Therefore some verifications and discussions of the characteristics of FIB sputtering results according to focal length were described in this paper. And we suggested the definition of rectangular pattern profile and made the verifications of sputtering results based on definition of it.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.643-652
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• 2009

This paper presents brief history and a state-of-the-art survey of Life Cycle Cost (LCC) analysis, in particular LCC analysis in the Urban Transit Vehicle, based on a internationl codes and standards related to LCC analysis. A main objective of the LCC analysis is to quantify the total cost of ownership of a product throughout its full life cycle, which includes research and development, construction, operation and maintenance, and disposal. The predicted LCC is useful information for decision making in purchasing a product, in optimizing design, in scheduling maintenance, or in planning overhaul. This paper presents a LCC procedure consisting of seven steps, which are "Problems definition", "Cost elements definition", "System modeling", "Data collection", "Cost profile development", "Evaluation", and "Verification". Sub-activities to be encompassed in the seven steps procedure are described.

• 산업경영시스템학회지
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• 제40권2호
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• pp.145-149
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• 2017

One of the challenges facing precision manufacturers is the increasing feature complexity of tight tolerance parts. All engineering drawings must account for the size, form, orientation, and location of all features to ensure manufacturability, measurability, and design intent. Geometric controls per ASME Y14.5 are typically applied to specify dimensional tolerances on engineering drawings and define size, form, orientation, and location of features. Many engineering drawings lack the necessary geometric dimensioning and tolerancing to allow for timely and accurate inspection and verification. Plus-minus tolerancing is typically ambiguous and requires extra time by engineering, programming, machining, and inspection functions to debate and agree on a single conclusion. Complex geometry can result in long inspection and verification times and put even the most sophisticated measurement equipment and processes to the test. In addition, design, manufacturing and quality engineers are often frustrated by communication errors over these features. However, an approach called profile tolerancing offers optimal definition of design intent by explicitly defining uniform boundaries around the physical geometry. It is an efficient and effective method for measurement and quality control. There are several advantages for product designers who use position and profile tolerancing instead of linear dimensioning. When design intent is conveyed unambiguously, manufacturers don't have to field multiple question from suppliers as they design and build a process for manufacturing and inspection. Profile tolerancing, when it is applied correctly, provides manufacturing and inspection functions with unambiguously defined tolerancing. Those data are manufacturable and measurable. Customers can see cost and lead time reductions with parts that consistently meet the design intent. Components can function properly-eliminating costly rework, redesign, and missed market opportunities. However a supplier that is poised to embrace profile tolerancing will no doubt run into resistance from those who would prefer the way things have always been done. It is not just internal naysayers, but also suppliers that might fight the change. In addition, the investment for suppliers can be steep in terms of training, equipment, and software.

• Geomechanics and Engineering
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• 제20권4호
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• pp.275-285
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• 2020

Excavation usually induces considerable ground settlement in soft ground, which may result in damage of adjacent buildings. Generally, the settlement is predicted through elastic-plastic finite element method and empirical method with defects. In this paper, an analytical solution for predicting ground settlement induced by excavation is developed based on the definition of three basic modes of wall displacement: T mode, R mode and P model. A separation variable method is employed to solve the problem based on elastic theory. The solution is validated by comparing the results from the analytical method with the results from finite element method(FEM) and existing measured data. Good agreement is obtained. The results show that T mode and R mode will result in a downward-sloping ground settlement profile. The P mode will result in a concave-type ground settlement profile.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2004년도 가을 학술발표논문집 Vol.31 No.2 (1)
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• pp.292-294
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• 2004

이동통신사가 선택한 컨텐츠만이 사용자들에게 서비스 될 수 있는 환경에서 다양한 컨텐츠 서비스의 제공을 기대하기는 어려운 실정이다. 이 같은 문제를 해결하기 위해 서비스 제공자들은 이동통신회사의 전송망을 대여하여 자신들의 모바일 포털 서비스를 통해 사용자들에게 다양한 컨텐츠를 제공할 수 있다. 그러나 개별적으로 관리되는 사용자 인증 서버를 통한 인증과정은 사용자들에게 반복적인 인증정보제공절차를 강요한다. 이러한 보안정보의 빈번한 노출로 인하여 잠재적인 보안 취약성이 야기된다. 단일인증이 보안정보 노출의 최소화를 위한 대안이 될 수 있지만 모바일 기기들의 성능적인 제약은 모바일 및 유비쿼터스 환경에 단일인증을 적용하는데 걸림돌이 되고 있다. 본 논문에서는 유무선 통합 환경에서 단일인증을 제공하기 위해 모바일 단말기와 유선도메인 간에 인증정보를 교환하는 profile을 정의하여 모바일 단말기의 성능적인 제약을 극복하기 위한 방안을 제시한다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2004년도 추계학술발표논문집(상)
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• pp.341-344
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• 2004

본 연구는 소프트웨어 재사용을 효과적으로 수행하기 위해 사용자 검색 피드백을 지원할 수 있는 유저 프로필을 정의하였다. 컴포넌트 검색을 위해 퍼지 함수를 이용한 신뢰값을 사용하였으며, 사용자 집단의 요구에 능동적으로 반응할 수 있도록 퍼지 함수를 변화시켜 컴포넌트의 검색 우선순위를 변경시키는 방법을 사용하였다. 본 연구에서는 사용자 피드백을 반영하는 퍼지화 함수에 유저 프로필을 적용하여 사용자 등급에 따라 사용자 의견이 시스템에 반영되는 정도를 다르게 해주었다. 본 연구의 사용자 검색 피드백 방법은 퍼지 기법을 적용한 퍼지화 함수와 유저 프로필을 이용하여 시스템을 장기간에 걸쳐 서서히 변화시킬 수 있도록 하였다.

• 대한의생명과학회지
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• 제18권3호
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• pp.260-267
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• 2012

Obesity is associated with cardiovascular risk factors, such as dyslipidemia, hypertension and diabetes. However the presence of the obesity related deranged metabolic profiles varies widely among obese individuals. These individuals, known as 'metabolically healthy obese phenotype (MHO)', despite having excessive body fatness, display favorable metabolic profiles characterized by insulin sensitivity, no hypertension, as well as less dyslipidemia, less inflammation. The purpose of this study was to compare cardiac characterization and clinical profile of MHO and Non-MHO (nonmetabolically healthy obese) subjects in men. We measured treadmill exercise capacity (METs) and maximum blood pressure (BP) in 210 subjects through a medical checkup at J General Hospital. Metabolic syndrome was defined according to the modified Adult Treatment Panel III definition criteria. Both MHO and Non-MHO subjects showed statistically significant changes in the left ventricular mass index (P<.001, P<.01, respectively), A-velocity (P<.01, P<.001, respectively), E/A ratio (P<.01, P<.001, respectively), E'-velocity (P<.001, P<.001, respectively), HOMA-IR (P<.01, P<.001, respectively) and maximum systolic BP (P<.01, respectively) compared with the MH-NO (metabolically healthy non obese) subjects. In conclusion, MHO participants were at increased risk of cardiovascular disease and partly metabolic disorder.

• 한국정밀공학회지
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• 제23권2호
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• pp.88-96
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• 2006

A gerotor pump is suitable for oil hydraulics of machine tools, automotive engines, compressors, constructions and other various applications. Especially the pump is an essential machine element of an automotive engine to feed lubricant oil. The subject of this paper is the theoretical analysis of the internal lobe pump which is a particular type of positive displacement pump. The main components of the pump are rotors; usually the outer rotor profile is characterized by lobes with circular shape, while the inner rotor profile is determined as conjugate as the outer rotor profile. For this reason the topic presented here is the definition of the geometry of the rotors starting from the design parameters. The choice of these parameters is subject to some limitations in order to avoid cusp and loop between rotors. And the integrated system which is composed of three main modules has been developed through AutoLISP & Visual Basic and CAD considering various design parameters. It generates automatically an designed model for a general type of a gerotor pump and allows us to calculate two performances indexes commonly used for the study of positive displacement pumps: the flow rate and flow rate irregularity. Results obtained using the system enable the designer and manufacturer of oil pump to be more efficient in this field.