• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제28회 추계학술대회
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• pp.221-226
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• 1998

The processing conditions for the mass production of platelet WS$_2$ lubricant powder were optimized. The mixture of tungsten and sulfur powders was sealed in a vacuum of 10$^{-3}$ torr and heat-treated at 850$\circ$C for 2 h. The internal pressure of reaction chamber was maintained at certain level by controlling the release valve automatically. The reaction product was the platelet WS$_2$ powder with an average size of 15 $\mu$m. The synthesized WS$_2$ powder was then coated on the wiper-blade of automobiles and the commercial deep-grooved ball bearing using wet and dry coating methods, respectively. High lubricity and wear resistance of wet coated wiper-blade were confirmed by the life test of 70,000 cycles. The life-time of the ball bearing assembled after WS$_2$ coating onto each part increased 50 times compared to the non-coated ball bearing.

• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1491-1497
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• 2007

Arginine deiminase (ADI, E.C. 3.5.3.6), one of the arginine deprivation enzymes, exhibits anticarcinogenic activities. The present study investigated the anti-inflammatory activities of the purified recombinant ADI originating from Lactococcus lactis ssp. lactis ATCC7962 (LADI). LADI dose-dependently inhibited lipopolysaccharide (LPS)-induced upregulation of inducible nitric oxide synthase and the production of nitric oxide in RAW 264.7 murine macrophages. The induction of cyclooxygenase-2 expression and subsequent production of prostaglandin $E_2$ by LPS was also attenuated by LADI treatment. Moreover, LADI inhibited the production of interleukin-6 in LPS-stimulated RAW 264.7 macrophages. These results indicate that LADI exerts anti-inflammatory effects, which may in part explain its chemopreventive potential.

• 경영과학
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• 제18권2호
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• pp.97-105
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• 2001

For the airplane manufacturing industry, to decide the sloe of developing airplane is very important because it affect the developing costs, the type of production industry like national independence production or international cooperation production, etc.. And the decision must be made by the base of national aviation industry, status of technology, economic factors and national and international demand, etc. This paper was studied to present a model for the application of AHP to the decision of optimum size of Korean developing airliner. For this study, a questionnaire was developed In respect to the criteria of developing airliner and given to 50 of professors, researchers and experts who participated in this part. The AHP software developed by Korean Advanced Institute of Science Technology (KAIST) was used to analyze the data.

• 한국정밀공학회지
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• 제18권2호
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• pp.111-118
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• 2001

Tungsten probe is the most important part of a probe card, which is widely used for the performance test of wafer chips. Electro chemical etching becomes an exclusive choice for mass production of the tungsten probes. In the mass production, not only the shape of the probe but also the shape distribution of machined probes is important. A new method is proposed for the mass production of the tungsten probes. Tungsten wires are separated by a distance, and dipped into electrolyte. The dipping rate is controlled to shape the probes. Several experimental tests are performed to study the machining characteristics. From the test results, machining parameters including electrical conditions and anode position showed significant influences on the shape, repeatability, precision and quality of sharp tips.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.747-749
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• 2006

SMS Meer GmbH, formerly Mannesmann and today part of the SMS Group, has been building powder presses since the early 1950s. The patents developed here in this field have long since documented the pioneering work carried out for the PM industry. The paper focuses on the challenge of reconciling the contradictory demands in the production of highly complex and crack-free PM parts. The process employed with the patented Controlled Punch Adapter (CPA) [1] counters possible cracking reliably and directly at the source. In this way is it possible to develop new and highly complex parts to series production maturity in a minimum of time even without simulation of the press cycle [2]. The quality data achieved in the production series, almost 100% crack and micro crack-free green parts with optimum density distribution over all press levels is unrivalled and thus gives the user a clear lead over the competition.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2001년도 춘계학술대회 논문집
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• pp.295-300
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• 2001

The progressive die performs a series of fundamental sheet metal working, particularly this study regards to develop the center carrier feeding type die for thick sheet metal(SS41, 2.5mm) production that is a specific division. In order to prevent defect on the production, the analysis of production part, optimum design of strip process layout, die design and die making and tryout etc. are necessary. In this study, we designed and predicted a progressive die of multi stages by wide collected data base and computer aided method.

• 한국자동차공학회논문집
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• 제13권4호
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• pp.26-31
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• 2005

ITR(Inne. Tie Rod) is one of the core parts in an automobile steering system. The front wheels are connected to the steering system, which are controlled by steering wheel through the ITR. Improvement of assembling ITR is needed f3r drivers' satisfaction. Therefore, the parameters influencing the rotational torque were studied and analyzed. The useful results can be obtained, and could be applied to manufacture ITR. Through these manufacturing technologies, high quality ITR have been manufactured with high productivity.

• 산업공학
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• 제6권2호
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• pp.53-65
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• 1993

This paper deals with the development of a software module for production planning and scheduling activities of an existing Flexible Machining and Assembly System (FMAS). The Production Planning Module uses the hierarchical and sequential scheme based on "divide and conquer" philosophy. In this module, routes are determined based on the production order, orders are screened, tools are allocated, and order adjustments are executed according to the allocated tools. The Scheduling Module allocates the resources, determines the task priority and the start and completion times of tasks. Re-scheduling can be done to handle unforeseen situations such as lumpy demands and machine breakdowns. Since all modules are integrated with a central database and they interface independently, it is easy to append new modules or update the existing modules. The result of this study is used for operating the real FMAS consisting of a machining cell with 2 domestic NC machines and a part feeding robot, an assembly cell with a conveyor and 3 robots, an inspection cell, an AGV, an AS/RS, and a central control computer.

• 대한방사성의약품학회지
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• 제1권2호
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• pp.98-103
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• 2015

Good manufacturing Practice (GMP) regulation for diagnostic and therapeutic radiopharmaceuticals was prepared at 2014. The mandatory GMP regulation becomes effective on $1^{st}$, July 2015,with two years of grace periods. Korean radiopharmaceuticals GMP regulation was consisted of quality management, personnel, premise and facility, documentation, production, quality control and self-audit and they have a very similar structure to European Union and PIC/S GMP regulation. Here, we describe detailed description of GMP regulation each part and application to radiopharmaceuticals production. And we also compare Korea, Japan and USA radiopharmaceuticals GMP regulation. GMP is a method to maintain quality of radiopharmaceuticals in daily production and it must be embedded on the manufacturing operation and management.

• 말소리와 음성과학
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• 제14권1호
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• pp.13-19
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• 2022

This study analyzed the pronunciations of Japanese fricative /s/ and affricate /ts/ by 24 Japanese and 40 Korean speakers using the rise and steady+decay durations of their frication part in order to clarify the characteristics of their pronunciations. Discriminant analysis revealed that Japanese speakers' /s/ and /ts/ were well classified by the acoustic boundaries defined by a discriminant function. Using this boundary, Korean speakers' production of /s/ and /ts/ was analyzed. It was found that, in Korean speakers' pronunciation, misclassification of /s/ as /ts/ was more frequent than that of /ts/ as /s/, indicating that both the /s/ and /ts/ distributions shift toward short rise and steady+decay durations. Moreover, their distributions were very similar to those of Korean fricatives and affricates. These results suggest that Korean speakers' classification error might be because of their use of Korean lax and tense fricatives to pronounce Japanese /s/, and Korean lax and tense affricates to pronounce Japanese /ts/.