• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2001년도 The Pacific Aisan Confrence On Intelligent Systems 2001
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• pp.224-229
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• 2001

When a semiconductor package is assembled, various materials such as die attach adhesive, lead frame, EMC (Epoxy Molding Compound), and gold wire are used. For better preconditioning performance, the combination between the packaging materials by studying the compatibility of their properties as well as superior packaging material selection is important. But it is not an easy task to find proper packaging material sets, since a variety of factors like package design, substrate design, substrate size, substrate treatment, die size, die thickness, die passivation, and customer requirements should be considered. This research applies case-based reasoning(CBR) technique to solve this problem, utilizing prior cases that have been experienced. Our particular interests lie in building decision support model to aid the selection of proper die attach adhesive. The preliminary results show that this approach is promising.

• 한국안전학회지
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• 제30권2호
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• pp.27-34
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• 2015

Nowadays, remodeling cases for some apartment like Hyundai through the support of government are reported. Conventionally, balcony and aisle are extended for additional private area or balcony which is supported by new frame is extended. In extension work at site, dowel bar is conventionally inserted in old concrete slab for connection with old and new slab, however, an examination for structural safety is rarely performed prior to construction, if ever, vertical load is only considered for structural analysis. When conventionally connected structures are exposed to earthquake, the old and new structures have individual earthquake behavior with different mode, which may lead the elimination of resistance to earthquake in new structures. As of this reason, new detailing connection system which can have light weight and sufficient ductility performance is developed for application to domestic extension works. Additionally, user manual and specification are also developed for fertilization of application for the developed technology.

• 품질경영학회지
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• 제27권4호
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• pp.266-279
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• 1999

Today, Companies are facing the harsh realities of a competitive environment. This is no time for revolutionary change. Instead, Companies are instituting revolutionary change meant to have impact within a very short time frame. Bold steps are required to lead the industry into a future of improved efficiency and significant productivity gains. GE, as well as Intel, Motorola, and other companies adopted a program called Six Sigma, in order to make fundamental changes in the way the company operated to fulfill customers'expectations. Six sigma reduces the occurrence of defects from a 3 sigma level of 66,800 defects per million to a 6 sigma level-less than 4defects per million. The goals and metrics of the company's Six Sigma process clearly have had a positive effect on customer satisfaction and customer perception of the company.

• BMB Reports
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• 제45권11호
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• pp.604-611
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• 2012

Recent advances in genome and transcriptome analysis have enabled identification of numerous members of a new class of noncoding RNA, long noncoding RNA (lncRNA). lncRNAs are broadly defined as RNA molecules greater than 200 nt in length and lacking an open reading frame. Recent studies provide evidence that lncRNAs play central roles in a wide range of cellular processes through interaction with key component proteins in the gene regulatory system, and that alteration of their cell- or tissue-specific expression and/or their primary or secondary structures is thought to promote cell proliferation, invasion and metastasis. The biological and molecular characteristics of the large majority of lncRNAs remains unknown, and it is anticipated that improved understanding of the roles played by lncRNAs in cancer will lead to the development of novel biomarkers and effective therapeutic strategies.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1978.1_1979.1
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• 2009

In this paper, we have proposed and demonstrated a tonometry sensor array for measuring arterial pulse pressure. A sensor module consists of 7 piezoresistive pressure sensor array. Wire-bonded connection was provided between silicon chip and lead frame. PDMS(poly-dimethylsiloxane) was coated on the sensor array to protect fragile sensor while faithfully transmitting the pressure of radial artery to the sensor. Tonometric pulse pressure can be measured by this packaged sensor array that provides the pressure value versus the output voltage.

• International Journal of Precision Engineering and Manufacturing
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• 제2권1호
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• pp.26-32
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• 2001

An ecpert system for rotationally symmetric deep drawing products has been developed. The application for non-axisymmetric components, however, has not been reported yet. This study construsctus and expert system for non-axisymmetric motor frame which shape is classified into ellipse in deep draqing process and investigates process sequence design with elliptical shape. The developed system consists of four modules. The first is recognition of calculate surface area for non-axisymmetric products. The third is blank design module the creates an oval-shaped blank with the same surface area. The fourth is a processplanning module based on production rules that play the best important roles in an expert system for manufacturing .The production rules are generated and upgraded by interviewing field engineers. Especially, drawing coefficient, punch and die radii for elliptical shape products are considered as main design parameters. The constructed system for elliptical deep drawing product would be very useful to reduce lead time and improve accuracy for products.

• Structural Engineering and Mechanics
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• 제13권1호
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• pp.35-52
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• 2002

It was shown in the previous study (Lee and Bertero 1993) that incremental collapse can lead to the exhaustion of the plastic rotation capacity at critical regions in a structure when subjected to the number of load cycles and load intensities as expected during maximum credible earthquakes and that this type of collapse can be predicted using the shakedown analysis technique. In this study, a minimum-weight design methodology, which takes into account not only the prevention of this incremental collapse but also the requirements of the serviceability limit states, is proposed by using the shakedown analysis technique and a nonlinear programming algorithm (gradient projection method).

• Architectural research
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• 제2권1호
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• pp.47-54
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• 2000

The critical load of a continuous compression member was determined by the beam-analogy method. The proposed method utilizes the stress-analysis results of the analogous continuous beam, where imaginary concentrated lateral load changing its direction is applied at each midspan. The proposed method gives a lower bound error of critical load and can predict the span that buckles first. The effective length factors for braced frame columns can be easily determined by the present method, but result in the upper bound errors in all cases, which can lead to a conservative structural design.

• 한국방재학회 논문집
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• 제7권5호
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• pp.159-166
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• 2007

Large scale flood disasters bring human losses and properties, which lead to the decrease of our productive value and change social environment. Human loss and economic damage are considered to be the same system but they are viewed as separated systems. The total amount of human loss can be represented as the total amount of economic damage estimated in the frame of social system while it will be possible to make mutual changing by clearing the relations between social and economic systems. In this regard, an attempt to estimate economic loss considering per capita Gross Domestic Production (GDP) caused by flood-related mortality was carried out to the typhoon Rusa of 2002 in Kangwon-do. The proposed method tried to capture quantitative factors which are affecting the loss of per capita GDP. The approach has great importance not only to set up governmental policy but also methodological progress in the research due to impact of disaster-related mortality on GDP loss.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1993년도 추계학술대회 논문집
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• pp.49-54
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• 1993

This paper discusses the reliability of solder joints of electronic devices on printed circuit board. Solder application is usually done by screen printing method for the bonding between outer leads of devices and thick film(Ag/Pd) pattern on Hybrid IC as wel1 as Cu lands on PCB. As result of thermal stresses generated at the solder joints due to the differences of thermal expansion coefficients between packge body and PCB, Micro cracking often occurs due to thermal fatigue failure at solder joints. The initiation and the propagate of solder joint crack depends on the environmental conditions, such as storage temperature and thermal cycling. The principal mechanisms of the cracking pheno- mana are the formation of kirkendal void caused by the differences in diffusion rate of materials, ant the thermal fatigue effect due to the differences of thermal expansion coefficient between package body and PCB. Finally, This paper experimentally shows a way to supress solder joints cracks by using low-${\alpha}$ PCB and the packages with thin lead frame, and investigates the phenomena of diffusion near the bonding interfaces.