• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.2
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• pp.51-57
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• 2013

The current expanding mobile markets incessantly demands small form factor, low power consumption and high aggregate throughput for silicon-level integration such as memory to logic system. One of emerging solution for meeting this high market demand is 3D through silicon stacking (TSS) technology. Main challenges to bring 3D TSS technology to the volume production level are establishing a cost effective supply chain and building a reliable manufacturing processes. In addition, this technology inherently help increase number of IOs and shorten interconnect length. With those benefits, however, potential signal and power integrity risks are also elevated; increase in PDN inductance, channel loss on substrate, crosstalk and parasitic capacitance. This paper will report recent progress of wide IO memory to high count TSV logic device assembly development work. 28 nm node TSV test vehicles were fabricated by the foundry and assembled. Successful integration of memory wide IO chip with less than a millimeter package thickness form factor was achieved. For this successful integration, we discussed potential signal and power integrity challenges. This report demonstrated functional wide IO memory to 28 nm logic device assembly using 3D package architecture with such a thin form factor.

• Journal of Sensor Science and Technology
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• v.21 no.2
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• pp.114-120
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• 2012

This paper describes the design, fabrication and testing of a micromachined resonant accelerometer consisting of a symmetrical pair of proof masses and double-ended tuning fork(DETF) oscillators. Under the external acceleration along the input axis, the proof mass applies forces to the oscillators, which causes a change in their resonant frequency. This frequency change is measured to indicate the applied acceleration. Pivot anchor and leverage mechanisms are adopted in the accelerometer to generate larger force from a proof mass under certain acceleration, which enables increasing its scale factor. Finite element method analyses have been conducted to design the accelerometer and a silicon on insulator(SOI) wafer with a substrate glass wafer was used for fabricating it. The fabricated accelerometer has a scale factor of 188 Hz/g, which is shown to be in agreement with analysis results.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.5
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• pp.463-474
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• 2003

In this research, adult women＇s shoulder types were Classified through direct and indirect measurements to present a judging individual body size according to the type. Also, regression formula by shoulder types were calculated and presented the basic bodice pattern. The results were as follows: 1. The result of factor analysis indicated that 6 factors were extracted through factor analysis and those factors comprised 66.1 to of total variance. 2. By using factor scores, cluster analysis was carried out and subject were classified into 5 clusters. Type 1 was the inclined shoulders, wide shoulders and passive posture. Type 2 was the front type shoulders and active posture. Type 3 was the thick shoulders and back type shoulders. Type 4 was the narrow shoulders. Type f was the drooped shoulders, thin shoulder and sway posture. 3. The body types of individuals were judged by discriminant analysis. 4. After setting 4 items such as the bust girth, posterior waist length, neck base girth and waist girth as representative items and regression formulas were presented. the superiority of the final basic bodice patterns were demonstrated by high approval rate of the subjects who participated in testing.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.11
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• pp.1362-1376
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• 2011

This study examines the effect of the structural properties of F/W wool knit fabrics for woman's knitwear on the perceptions of textures and sensible images of consumers and present basic data for textile designing by analyzing the relationship among the structural properties, mechanical properties, objective hand measurements and preferences. A total of 12 kinds of knit fabrics were prepared and investigated in terms of the differences in the subjective, mechanical properties and objective hand measurements according to the structural properties of knit fabrics. The data were analyzed by t-test. The subjective hand attributes of wool knits through factor analysis are categorized into 6 factors. In particular, the 'active/comfort' factor is a meaningful result that reflects the unique characteristics of knit fabrics compared to woven fabrics. Mechanical properties and objective hand measurements have a greater effect on textures than on sensible images; in addition, the structural properties, 'gauge' was the most important factor to influence the subjective evaluation.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.6
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• pp.379-386
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• 2012

The purpose of this study was to evaluate whether berberine (BER) administration could attenuate depression- and anxiety-like behaviors and increase corticotrophin-releasing factor (CRF) and tyrosine hydroxylase (TH) expression following chronic morphine withdrawal in rats. Male rats were exposed to chronic, intermittent, escalating morphine (10~50 mg/kg) for 10 days. After the last morphine injection, depression- and anxiety-like beahvior associated with morphine discontinuation persisted for at least three days during withdrawal without any change in ambulatory activity. Daily BER administration significantly decreased immobility in the forced swimming test and increased open-arm exploration in the elevated plus maze test. BER administration also significantly blocked the increase in hypothalamic CRF expression and TH expression in the locus coeruleus (LC) and the decrease in hippocampal brain-derived neurotrophic factor (BDNF) mRNA expression. Taken together, these findings demonstrated that BER administration significantly reduced morphine withdrawal-associated behaviors following discontinuation of repeated morphine administration in rats, possibly through modulation of hypothalamic CRF and the central noradrenergic system. BER may be a useful agent for treating or alleviating complex withdrawal symptoms and preventing morphine use relapses.

• Journal of Navigation and Port Research
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• v.31 no.2
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• pp.133-139
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• 2007

Relative importance of maritime transport that takes charge of main current of freight in country' economy is very large. Especially, port and facility carry out important role which treats freight of import and export smoothly and improves international trade as turning point, to achieve key role on connection and association between sea and land. For such reason, enlargement of port facilities or development of port needs to grasp exactly the utilization of port, attributes and selective factors of shipper. On the other hand, the amounts of physical distribution on Mokpo port located in Korean west coast are increasing, with fast economic growth of East Asian including China. This study uses discrete choice model that is measuring to analyze attribute and characteristic of Mokpo port, and analyzes port selection by decision factors of shipper. This paper composed a questionnaire using the result of preceding research, to decide port selection factor among competitive ports. Through factor analysis on a basis of the questionnaire' result, five principal components were extracted. These are resorted out by Logit model, to grasp competitive elements of port. This research fin present direction which raises competitive power of ports in west coast of Korea, especially on alternative and concentration of middle-class port as Mokpo may be useful.

• Journal of the military operations research society of Korea
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• v.33 no.1
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• pp.1-18
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• 2007

In the early stage of weapon system acquisition process, acquisition policy is necessarily established to acquire weapon system in a faster, better, cheaper way. Several alternatives, such as "buy", "domestic research and development", and "technical corporative production", can be considered for the best acquisition policy making. However, the comparison factors for those alternatives have different metrics and values. Therefore, the aim of this paper is to suggest KAAM(Knowledge-based Alternatives Analysis Model) as a scientific method to compare the alternatives having such different metrics and values and giving a weighted and normalized single measurement for the easy comparison. KAAM is a hybrid model incorporating Satty technique, Delphi/Shang method, Consensus method, and SAW method. KAAM is implemented on Microsoft Excel environment and provided tabular form user interface. Finally, an illustrative example is shown using KAAM.

• The Mathematical Education
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• v.49 no.4
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• pp.501-522
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• 2010

In this study, 'Instruments of the achievement attribution in mathematical learning' was develop to investigate the reasons of mathematical learning achievement by reflecting Korean middle school and high school students' psychological characters and learning context in mathematical learning. To develop the appropriate items for the achievement attribution in mathematical learning, after reviewing attribution literature thoroughly, first version of the instrument was developed and Exploratory Factor Analysis and Confirmatory Factor Analysis were conducted. Then, to reduce the effect of the gender difference and achievement level difference, Differential Item Functioning was performed. Also, using Multiple group Confirmatory Factor Analysis, this instrument was investigated to see whether this can be used for both middle school and high school. The final items for success attribution are 3 items for luck, 3 items for effort, 2 items for ability. The failure attribution were composed of 3 items for luck, 3 items for effort, 2 items for ability, and 2 items for other. The instrument was developed by using large samples and psychometric analysis. Therefore, mathematic teachers can use this instrument efficiently to make a foundation for better learning environment so students' cognitive area and affective area can be harmonized.

• Structural Engineering and Mechanics
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• v.72 no.1
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• pp.31-41
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• 2019

Structural integrity assessment of piping components is of paramount important for remaining life prediction, residual strength evaluation and for in-service inspection planning. For accurate prediction of these, a reliable fracture parameter is essential. One of the fracture parameters is stress intensity factor (SIF), which is generally preferred for high strength materials, can be evaluated by using linear elastic fracture mechanics principles. To employ available analytical and numerical procedures for fracture analysis of piping components, it takes considerable amount of time and effort. In view of this, an alternative approach to analytical and finite element analysis, a model based on relevance vector machine (RVM) is developed to predict SIF of part through crack of a piping component under fatigue loading. RVM is based on probabilistic approach and regression and it is established based on Bayesian formulation of a linear model with an appropriate prior that results in a sparse representation. Model for SIF prediction is developed by using MATLAB software wherein 70% of the data has been used for the development of RVM model and rest of the data is used for validation. The predicted SIF is found to be in good agreement with the corresponding analytical solution, and can be used for damage tolerant analysis of structural components.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.189-189
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• 2015

본 연구는 기후변화의 영향을 고려한 포아송 강우생성모형의 일종인 MBLRP(Modified Bartlett-Lewis Rectangular Pulse)를 개발하고, 대한민국 주요 도시에 대해 향후 100년간 강우의 변화를 살펴보았다. 기존 MBLRP 모형에서 기후변화에 따른 강우량 변화를 고려할 수 있도록 GCM 모형의 강우 자료를 활용하였고, GCM 모형으로부터 발생하는 불확실성을 고려하기 위해 IPCC의 RCP(Representative Concentration Pathways) 시나리오를 모의한 16개의 GCM 모형을 사용하였다. 2007년부터 2099년까지의 미래기간을 3개의 시 구간으로 구분하고, 16개 GCM 앙상블을 사용하여 미래기간 동안 대한민국 16개 도시에 대해 1000개의 샘플을 BWA 방법을 이용하여 생성하였다. 제어기간(1973-2005) 대비 미래기간(2007-2099)의 변화율을 나타내는 FOC(factor of change)와 온도의 연별 변화율을 나타내는 SF(scaling factor)의 개념을 결합하여 미래기간에 대한 CF(correction factor)를 산정하였다. 이때 CF는 16개 도시의 연 단위 강우량 변화 비율을 월별로 나타내며, 제어기간의 월 강우 관측치와 CF를 몬테카를로 모의를 실시하여 미래기간의 강우 시나리오를 산정한다. 이를 통해 월 평균 강우량 통계치를 연 단위로 얻을 수 있으며, 월 평균 강우량이 월 평균 분산, 무강우확률, 자기상관계수와 가지는 선형 관계를 통해 강우 통계치를 산출한다. 이와 같은 강우 통계치는 가상강우생성모형인 MBLRP 모형에 입력 자료로 활용되어 월 강우량을 시 단위의 강우 시계열 자료로 생성해낸다. 최종적으로 MBLRP 모형으로 산정된 시 단위 강우 시계열은 기후변화 영향을 고려한 GCMs 앙상블로 생성된 강우 시나리오를 기반으로 산출되기 때문에 향후 수자원 분석에 활용 가능할 것이라 기대된다.