• Transactions of the Korean Society of Machine Tool Engineers
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• 제17권1호
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• pp.21-28
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• 2008

The final polishing process is based on slurry, pad, conditioner, equipment. Therefore, the concept of wafer final polishing is also necessary for repeatability of results between polished wafers. In this study, the machining conditions have a pressure, table speed, machining time and slurry ratio. This research investigated the surface characteristics that apply variable machining conditions and response surface methodology was used to obtain more flexible and optimumal condition base on Taguchi method. On the base of estimated response surface curvature from the equation and results of Taguchi method, combined design of experiment was considered to lead to optimumal condition. Finally, polished wafer was obtained mirror like surface.

• Journal of the Korea Furniture Society
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• 제10권2호
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• pp.29-36
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• 1999

During a radio-frequency/vacuum plus press drying process of some hardwood veneers for decoration we investigated the effect of a grain and thickness of a veneer sheet on drying rates, variations of final moisture content within a bundle of veneer sheets, and formation of checking, end waving, and burning mark. About thirty three hundreds sheet of veneer could be dried in sixty five hours from green to in0-use moisture content, and a final moisture content was significantly effected by initial moisture content of veneer. There were nearly variations in a final moisture content among the veneer sheets in the same bundle. A checking was never found in a edge-sliced veneer, and very slight in a flat-sliced veneer of ash and red oak. There were no end waving and no burning mark in all veneer sheets.

• Proceedings of the KSPS conference
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• 대한음성학회 1996년도 10월 학술대회지
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• pp.476-481
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• 1996

This paper explores to identify the stem-final consonants of p- and t-irregular verbs in Korean within the framework of Government Phonology. Since the advent of Generative Phonology, the phenomenon of irregular verbal conjugation has been of great interest to Korean phonologists both in linear and non-linear approaches. When we examine these analyses, we find that one of the major issues concerns the identities of the stem-final consonants of p- and t-irregular verbs. The proposals concerning this issue vary considerably from one another. In this paper, I put forward a different view from those proposals in that the stem-fmal consonants of p- and tirregular verbs are tensed p' and t' respectively.

• Journal of Korean Society for Quality Management
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• 제22권4호
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• pp.79-101
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• 1994

In modern manufacturing, a product consists of many components created by different processes. Variations in the individual component dimensions and in the processes may result in unacceptable final assemblies. Thus, engineers have increased pressure to properly set tolerance specifications for individual components and to control manufacturing processes. When a proper variation stack-up analysis is not performed for all of the components in a functional system, all component parts can be within specifications, but the final assembly may not be functional. Thus, in order to improve the performance of the final assembly, a proper variation stack-up analysis is essential for specifying dimensional tolerances and process control. This research provides a detailed case example of the use of variation stack-up analysis using a Monte Carlo simulation method to improve the defect rate of a complex process, which is the commutator brush track undercut process of an armature assembly of a small motor. Variations in individual component dimensions and process mean shifts cause high defect rate, Since some dimensional characteristics have non-normal distributions and the stack-up function is non-linear, the Monte Carlo simulation method is used.

• Transactions of Materials Processing
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• 제14권2호
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• pp.153-159
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• 2005

Design modification of the stamping die for the upper member of a front end module carrier is carried out in order to improve the surface quality of the final product. The small inferiority induced by wrinkling near the wall of the upper member has been inspected after the draw-forming process. The finite element analysis is pursued with the whole geometry in order to consider the complicated shape. The simulation shows that the excess metal is developed by the irregular contact of the blank the tool and it remains after the final stroke. This paper proposes two guidelines for the modification. One is to add the draw-bead near the critical region in order to increase the draw-in force. The other is to modify the tool shape such as the forming shape at the wall in order to absorb the excess metal before the final stroke. Simulation results show that the proposed guidelines both guarantee the improved surface quality.

• Clinical and Experimental Pediatrics
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• 제49권7호
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• pp.718-725
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• 2006

The pubertal activation of gonadotrophin releasing hormone(GnRH) requires coordinated changes in excitatory or inhibitory amino acids, growth factors, and a group of transcriptional regulators. The age of onset of puberty is progressing to younger age. Factors affecting early puberty include genetic traits, nutrition(body fat) and exposure to endocrine disrupting chemicals. In rapidly progressing central precocious puberty, gonadotrophin releasing hormone(GnRH) agonists(GnRHa) appear to increase final height if treated early stage. Further large scaled long-term follow-up study of the effects of GnRHa on final height is needed.

• Journal of applied mathematics & informatics
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• 제28권3_4호
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• pp.639-649
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• 2010

In this paper, a definition of interval-valued fuzzy regular language (IVFRL) is proposed and their related properties studied. A model of finite automaton (DFA and NDFA) with interval-valued fuzzy transitions is proposed. Acceptance of interval-valued fuzzy regular language by the finite automaton (DFA and NDFA) with interval-valued fuzzy transitions are examined. Moreover, a definition of finite automaton (DFA and NDFA) with interval-valued fuzzy (final) states is proposed. Acceptance of interval-valued fuzzy regular language by the finite automaton (DFA and NDFA) with interval-valued fuzzy (final) states are also discussed. It is observed that, the model finite automaton (DFA and NDFA) with interval-valued fuzzy (final) states is more suitable than the model finite automaton (DFA and NDFA) with interval-valued fuzzy transitions for recognizing the interval-valued fuzzy regular language. In the end, interval-valued fuzzy regular expressions are defined. We can use the proposed interval-valued fuzzy regular expressions in lexical analysis.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.184-187
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• 2002

Lovastatin is a cholesterol-lowering agent, which plays a role of an inhibitor of 3-hydroxy-3- methylglutaryl coenzyme A reductase (HMG-CoA). When thiamine was supplemented in 3L batch fermentation, the production of lovastatin was improved. At the same time, the levels of pyruvic acid and NAD(P)H were estimated in the course of the fermentation of A. terreus. For the high level production of lovastatin, semi fed-batch fermentation was performed. And the thiamine level was maintained to a concentration of 20 mg/L and glucose was supplied. The final dry cell weight was lowered by 30 % and final lovastatin concentration was increased by 33 %. Final lovastatin concentration of 3.3 g/L was achieved in 8 days.

• Journal of the Korean Institute of Landscape Architecture
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• 제28권4호
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• pp.105-116
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• 2000

The purpose of this paper is to minimize differences between landscape detailed design (hereafter 'design') and final landscape construction products in working sites (hereafter 'products'). Ten landscape sites constructed in recent two years were selected to examine the differences. Differences in quantities and quality between design and products were surveyed and the results were analyzed with the 'differential analysis method'. The method employed in this paper can be used as an optimization model to minimize the differences between design and products. This paper suggests that every landscape field should mark less than 13.672% calculated from the 10% of total amount for excellent construction products. This should be approved by the president, according to the Clause 20 of General Conditions of the Contract, divided by the ratio of quantities affecting mainly he average Difference in Value between Design and Construction(DVDC). This value can be the critical point from the differential analysis method for the optimal maximum DVDC between landscape design and final landscape construction products in fields.

• Phonetics and Speech Sciences
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• 제8권1호
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• pp.19-24
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• 2016

The Korean high back vowels /o/ and /u/ have been reported to be in a state of near-merger especially among young female speakers. Along with cross-generational changes, the vowel position within a word has been reported to render different phonetic realization. The current study examines native English speakers' ability to attend to the phonetic cues that distinguish the two merging vowels and the positional effects (word-initial vs. word-final) on the identification accuracy. 28 two-syllable words containing /o/ or /u/ in either initial or final position were produced by native female Korean speakers. The CV part of each target word were excised and presented to six native English speakers. The results showed that although the identification accuracy was the lowest for /o/ in word- final position (41%), it increased up to 80% in word-initial position. The acoustic analyses of the target vowels showed that /o/ and /u/ were differentiated on the height dimension only in word-initial position, suggesting that English speakers may have perceived the distinctive F1 difference retained in the prominent position.