• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2006년도 춘계학술대회
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• pp.149-152
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• 2006

In this paper, We study several method of CTQ measurement for improvement of Quality. Measurement are cornerstone of basic improvement of Science and Technology and are considered continuous thesis. In this paper, we survey measure several variable for CTQ for Six sigma. We introduce Taguchi's SN ration Which is important example good measure for improve quality Improvement are succeed by good select measure variable which is called CTQ which should agree problem define and final goal.

• 대한수학회보
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• 제49권1호
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• pp.155-163
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• 2012

Let E be an elliptic curve over $\mathbb{Q}$. Using Iwasawa theory, we give what seems to be the first general upper bound for the order of vanishing of the p-adic L-function at s = 0, and the $\mathbb{Z}_p$-corank of the Tate-Shafarevich group for all sufficiently large good ordinary primes p.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 추계학술대회 논문집
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• pp.489-496
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• 1998

Although the surface of aluminum alloy has good corrosion resistance property, the surface of the aluminum rolling stock should be painted for good appearance and protection of the body. For better painting of the aluminum carbody, the surface must also be well pretreated. In this paper, painting process of the aluminum rolling stock is described and the test results of the painted surface is presented. As accumulated data concerning to the painting technology for the aluminum rolling stocks are absent in our country, the presented test results will be helpful for mass production of aluminum rolling stocks in the near future.

• 한국정밀공학회지
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• 제14권1호
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• pp.29-51
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• 1997

The purpose of the survey is to identify possible new areas of research relating to nanotechnology and in particular areas in which the established facilities of the Centre for Metrology can be employed to good effect. This survey indicates that nanotechnology, a sub set of the more embracing Nano Science, is a rapidly developing discipline with good potential for Electronic and Mechanical Engineering. Nanotechnology includes three areas: Nanometrology, Nanometer positioning and Control, and Nanomanufacturing. In each of the areas, the current research situation and developing trends have been summarised. Possibilities for future work indicated.

• International Journal of Internet, Broadcasting and Communication
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• 제15권4호
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• pp.44-50
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• 2023

For Wi-Fi and IoT wireless systems, high-capacity wireless communication technology is being applied using MIMO OFDM. Because of virtu0al subcarriers in the practical MIMO OFDM system, the pilot subcarriers cannot be spaced equally. Thus, it is difficult to obtain a good mean square error (MSE) performance of the channel estimate. This paper proposes applicable methods and the newly discovered locations of pilot subcarriers in four transmitted antennas resulting in a good MSE performance with proposed optimization algorithms.

• Journal of Microbiology and Biotechnology
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• 제21권1호
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• pp.37-42
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• 2011

A new versatile acrylonitrile-bioconverting strain isolated from a petroleum-contaminated sludge sample and identified as Rhodococcus ruber AKSH-84 was used for optimization of medium and biotransformation conditions for nitrilase activity to produce acrylic acid. A simple and rapid HPLC protocol was optimized for quantification of acrylic acid, acrylamide, and acrylonitrile. The optimal medium conditions for nitrilase activity were pH of 7.0, temperature of $30^{\circ}C$, agitation of 150 rpm, and inoculum level of 2%. Glycerol as a carbon source and sodium nitrate as the nitrogen source provided good nutritional sources for achieving good biotransformation. Nitrilase activity was constitutive in nature and was in the exponential growth phase after 24 h of incubation under optimal conditions without addition of any inducer. The substrate preference was acrylonitrile and acetonitrile. The present work demonstrates the biotransformation of acrylonitrile to acrylic acid with the new strain, R. ruber AKSH-84, which can be used in green biosynthesis of acrylic acid for biotechnological processes. The nitrilase produced by the isolate was purified and characterized.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2623-2626
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• 2012

A series of functionalized furans were synthesized by way of a palladium-catalyzed coupling reaction of 2,3,5-trisubstituted furans with aryl chlorides through C-H bond cleavages at C-4 position. The feature of the reaction was facilitative preparation of furan derivatives with good functional group tolerance. All reactions gave the desired products in moderate to good yields in the presences of $BuAd_2P$ and t-BuOK in DMF at $120^{\circ}C$ after 15 h.

• Journal of Electrochemical Science and Technology
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• 제3권3호
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• pp.135-142
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• 2012

Over the past few years, $LiFePO_4$ has been actively studied as a cathode material for lithium-ion batteries because of its advantageous properties such as high theoretical capacity, good cycle life, and high thermal stability. However, it does not have a very good power capability owing to the low lithium-ion diffusivity and poor electronic conductivity. Reduction in particle size of $LiFePO_4$ to the scale of nanometers has been found to dramatically enhance the above properties, according to many earlier reports. However, because of the intrinsically low tap density of nanomaterials, it is difficult to commercialize this method. Many studies are being carried out to improve the volumetric energy density of this material and many methods have been reported so far. This paper provides a brief summary of the synthesis methods and electrochemical performances of micro-spherical $LiFePO_4$ having high volumetric energy density.

• 품질경영학회지
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• 제35권2호
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• pp.45-52
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• 2007

The danger of self-ignition of single base propellants will increase with time. Therefore, a good prediction of the safe storage time is very important. In order to determine the remaining shelf-life of the propellants, the content of stabilizer is determined. The propellants stored under normal storage conditions about 10 to 18 years were investigated and accelerated aging test was carried out by storing propellant sample at higher temperature. Finally, we analyzed the results by various methods in order to show the best way to predict the realistic shelf-life. The safe storage life of the propellants will be 24 years, at least 15 years. In case of applying Arrhenius's law, using the reaction rate constant at 28$^{\circ}C$ to 30$^{\circ}C$ to predict the shelf-life by accelerated aging test is reasonable for a good prediction.

• 한국군사과학기술학회지
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• 제12권6호
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• pp.808-814
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• 2009

Numerical flow-filed computations have been conducted around a projectile with a triangular ballute at Mach numbers of 0.3 ~ 0.9 and angles of attack of $0^{\circ}\;{\sim}\;30^{\circ}$. The expansion shape of a triangular ballute has been determined from both the manufacturing dimensions and the wind tunnel test results. It has been assumed that the shape does not alter after the ballute has been expanded completely. The computed results showed a good agreement with the wind tunnel test results. A sensitivity analysis on the aerodynamic coefficients has been performed to evaluate the quantitative effects on the flight performance. Trajectory simulation results were also in good agreement with the flight test results.