• Title/Summary/Keyword: reducing method

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Development and Applications of a Chemical Method for Sequential Analysis of Reducing Oligosaccharides

  • Hong, Seon-Pyo;Lee, Yong-Moon;Hiroshi-Nakamura
    • Archives of Pharmacal Research
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    • v.20 no.2
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    • pp.184-190
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    • 1997
  • A new method based on the chemical reaction has been devised for the sequential analysis of reducing oligosaccharides using 8-amino-2-naphthalenesulfonic acid (ANS), a fluorescent precolumn derivatization reagent for reducing saccharides. The procedure established includes 1) the derivatization of a reducing oligosaccharide to produce a Schiff base, 2) the reduction of the base with sodium cyanoborohydride $(NaBH_3/CN), 3)$ the methoxycarbonylation of the resultant secondary amino group, 4) the cleavage of the glycoside bond next to the reducing end, based on the intramolecular acid hydrolysis by the action of a sulfonic acid group of the ANS derivative, 5) the identification of the liberated reducing end by high-performance liquid chromatography (HPLC), and finally 6) the recovery of the resultant oligosaccharide fragment from the cleavage reaction mixture. The extensive examination of the conditions for the sequential analysis of reducing oligosaccharides resulted in the procedure of simplicity , high selectivity and high recovery. This procedure was found to be useful for the sequential analysis of di-, tri- and tetrasaccharides.

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A new Method for Reducing Harmonics in Input AC Line Currents of Converter by 2-4 Switching taps on Interphase Reactor (상간리액터의 2-4? 변환 방식에 의한 콘버어터 입력 전류의 고조파 저감에 관한 연구)

  • 유철로;이공희;이성룡
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.37 no.1
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    • pp.25-32
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    • 1988
  • In this paper, a new method for reducing harmonics in input AC line currents of converter is presented, which is due mainly to the equipment of 2-4 switching taps on interphase reactor. When this method is applicable to conventional 12 pulse converter, the 24 pulse converter, the 24 pulse or 48 pulse converter is controlled by firing angles. The former is performe in 2 tap method when less than 15 degrees, and the letter in 4tap method when more than 15 degrees. Therefore, the proposed method has the advantages of reducing harmonics in full range of control angle and comparison with the conventional 3 tap method. We proved the validity of that theoretically and experimentally.

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A Study on Reducing Speed Control of Hydraulic Motor of Textiles Supply Rolling Equipment (섬유공급 롤링장치의 유압모터 감속도 제어에 관한 연구)

  • 이재구;김도태;김성동
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2001.10a
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    • pp.62-67
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    • 2001
  • The textiles supply rolling equipment is a part of inspection machine which inspect finished textiles and it check up textiles through rolling hydraulic equipment. This study suggests a method to select the capacity and initial gas pressure of accumulator to control reducing speed of the hydraulic motor to a desired degree. An accumulator in hydraulic systems is hydraulic machinery which stores kinetic energy of inertia body during braking. A series of computer simulations were done for the brake action and the selection method was based upon a trial and error approach. The results of the simulation work were compared with those of experiments and these results show that the proposed method can be applied effectively to control reducing speed of the hydraulic motor when braking action in textiles rolling system.

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A Study on Bacterial Leaching of Low-Grade Copper Mineral(V) (저품위 동광석의 세균침출에 관한 연구 5)

  • 민봉희;박원구;이강순
    • Korean Journal of Microbiology
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    • v.12 no.1
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    • pp.25-30
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    • 1974
  • It was convinced that with a relatively small capital investment and with a low operating cost, appreciable amounts of cement copper could be produced from low-grade minerals by the application of a bacterial leaching method. For the recovery of cement copper from the impure pregnant solution, direct precipitation of copper with tin plates by a bacterial leaching method was feasible. The results obtained were as follows: 1)In order to remove the cement copper from the reducing metal, aeration and agitation method were more effective and economic than shaking method. 2)The rate of copper recovery from the pregnant solution was accerelated according to increasing quantities of reducing metal. However, the excess of reducing metal reduced the grade of cement copper. 3)Among the comparative experiments of copper recovery at each reaction temperature of $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$, the recovery rate of copper at $30^{\circ}C$from the pregnant solution was highest. 4)Direct cementation method on iron-containing metal was an excellent method for the recovery of cement copper in bacterial leaching.

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A Study on the Loss Reduction Method of Reinforcing Bar through Case Study

  • Park, U-Yeol;Jung, Hyeon-Ok;Kang, Tai-Kyung;Cho, Hun-Hee
    • Journal of the Korea Institute of Building Construction
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    • v.10 no.4
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    • pp.123-132
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    • 2010
  • Rebar work accounts for approximately 30% of the total construction costs for rebars and concrete. Recently, the high rising prices of rebars have become one of the principle factors of rising construction costs. Therefore, construction companies are putting much effort into loss reduction of rebars. Consequently, in this study, we wished to present loss reduction methods of rebars before the preparation of the placing drawings. To devise such methods, we collected previous case studies and analyzed methods that were applied for loss reduction. As a result of the analysis, we were able to find the following methods for loss reduction of rebars: method of reducing the number of splices at the mat foundation, method of reducing splice length at the internal columns or walls of the underground parking lot, method of reducing cap-ties of internal beams of basement floors excluding perimeter beams, and method of reducing anchorage length at the internal column or wall of the underground parking lot. Based on those analysis results, we presented our own loss reduction methods of rebars. Applying our methods resulted in considerable loss reduction.

Scene-based Nonuniformity Correction for Neural Network Complemented by Reducing Lense Vignetting Effect and Adaptive Learning rate

  • No, Gun-hyo;Hong, Yong-hee;Park, Jin-ho;Jhee, Ho-jin
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.7
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    • pp.81-90
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    • 2018
  • In this paper, reducing lense Vignetting effect and adaptive learning rate method are proposed to complement Scribner's neural network for nuc algorithm which is the effective algorithm in statistic SBNUC algorithm. Proposed reducing vignetting effect method is updated weight and bias each differently using different cost function. Proposed adaptive learning rate for updating weight and bias is using sobel edge detection method, which has good result for boundary condition of image. The ordinary statistic SBNUC algorithm has problem to compensate lense vignetting effect, because statistic algorithm is updated weight and bias by using gradient descent method, so it should not be effective for global weight problem same like, lense vignetting effect. We employ the proposed methods to Scribner's neural network method(NNM) and Torres's reducing ghosting correction for neural network nuc algorithm(improved NNM), and apply it to real-infrared detector image stream. The result of proposed algorithm shows that it has 10dB higher PSNR and 1.5 times faster convergence speed then the improved NNM Algorithm.

Estimation Method of Noise Reducing Devices Installed on the Noise Barrier(2) - Estimation by Sound Pressure Level - (방음벽 상단소음저감장치의 성능평가 방법에 관한 연구(2) - 음압레벨에 의한 평가 -)

  • Kim, Chul-Hwan;Chang, Tae-Sun;Lee, Ki-Jung;Kim, Dong-Joon;Jeong, Tae-Ryang;Chang, Seo-Il;Kim, Bong-Seok
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.11a
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    • pp.1125-1128
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    • 2007
  • In order to improve the acoustic performance of a noise barrier without increasing its height, various type of acoustic devices are suggested but, there is no proper method to estimate the performance in Korea. For this, an outdoor test facility was established in Expressway and Transportation Technology Institute(ETTI) of Korea Expressway Corporation for testing the acoustical performance of noise reducing devices installed on the top of a noise barrier. Noise measurements before and after installation of the noise reducing devices were carried out by using sound pressure level for long distance range from the barrier, from 10m to 40m. For considering the directivity effects of noise reducing devices, multivariate regression analysis was attempted.

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Current Variation Method for Reducing Torque Ripples of Linear Motor (선형 전동기의 상전류 조정을 통한 토크리플 저감법)

  • Kim, Min-Jae;Lim, Jae-Won;Jung, Hyun-Kyo
    • Proceedings of the KIEE Conference
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    • 2009.04b
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    • pp.85-87
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    • 2009
  • Linear motor is an energy conversion device which makes kinetic energy from electrical energy. This paper presents a method to reduce torque ripples by variation of the current. The torque ripples are basically caused by detent force so this method has a focus on reducing detent force. The torque ripples were calculated by finite element method.

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A New Converter System of Reducing Harmonics by 2-3 Switching Taps on Interphase Reactor (2-3 ? 변환방식에 의한 새로운 고조파 저감형 컨버어터 시스템)

  • Lee, Seong-Ryong
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.4
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    • pp.658-666
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    • 1987
  • In this paper, a new mehtod of reducing harmonics that involved in input AC line currents or in output DC voltage of the converter system is presented. which is due mainly to the quipment of 2-3 switching taps on interphase reactor. In case that the 3 tap method is applicable to conventional 12 pulse converter, it could not bring to an effect of reducing harmonics under firing angle 15\ulcorner To solve these problems, 24 pulse or 36 pulse converter is controlled by microprocessor. The former is performed in 2 tap method when \ulcorneris less than 15\ulcorner the latter in 3 tap method when it is more then 15\ulcorner Therefore the originality of this paper liea in microprocessor based equipment of the 2-3 switching taps on interphase reactor. I applied this method to the 12 pulse converter, and proved validity of that theoretically and experimentally.

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