• Title/Summary/Keyword: bulk method

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A case study of large - long tunnel using the charging mechanization system of the bulk emulsion explosives (Bulk Emulsion 기계화 장전시스템을 이용한 대단면 장대터널 시공사례연구)

  • Yoon, Ji-Sun;Jang, Young-Min;Lee, Sang-Hun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.11 no.2
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    • pp.107-115
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    • 2009
  • Lately, the length of tunnel, the number of large-long tunnel over three lanes are steeply increased because of the request for high speed and straight road. Therefore, the maximization of excavation efficiency is needed in tunnel construction. Bulk Emulsion explosives charging system is the spearhead equipment using the radio remote control $&$ mechanization system compare with a traditional method Cartridge type. This study introduced the bulk emulsion explosives which is new method in tunnel blasting and verified the efficiency of bulk emulsion explosives for long-large tunnel. And we tried to compare Cartridge type efficiency with bulk emulsion explosives efficiency by the field test.

Effect of Air Flow During Curing Process on Physical Properties of Bulk Cured Leaves (황색종 Bulk건조시 송풍량 조절에 따른 건조엽의 물리성 변화)

  • 이철환;진정의;한철수
    • Journal of the Korean Society of Tobacco Science
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    • v.21 no.1
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    • pp.5-9
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    • 1999
  • In recent years, the line of increase in policy on tobacco production triggered a rise in the loading volume per bulk curing barn, and manufacturers boosted the output of their blowers in order to prevent dirty leaves in the process of curing. for this reason, we studied the effect of the reducing air flow in bulk curing chamber from the color fixing stage to the stem drying stage of flue curing process on physical properties of cured leaves. The control of air flow was composed of the reducing air velocity of blower by means of a voltage regulator (slidac), and condition before color fixing stage was all the same with the conventional curing method. As a result, an effectiveness of improvement in the physical properties of cured leaves were observed. The leaves cured by this method were somewhat orange in color of upper stalk position, better bodied, and less brittle compared with the leaves produced by conventional curing. However, the leaves cured by this method had a little sharpness and harshness. As to the physical properties, there was decreased in occurrence of flat leaves than that of conventional ones. On the other hand, in case of reducing air flow during the curing process, increase of price per kg reached to about 5 % compared with those of conventional curing method.

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Estimation of Atmospheric Turbulent Fluxes by the Bulk Transfer Method over Various Surface (다양한 지표면 위에서 총체 전달 방법에 의한 대기 난류 플럭스 추정)

  • Kim, Min-Seong;Kwon, Byung-Hyuk;Kang, Dong-Hwan
    • Journal of Environmental Science International
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    • v.23 no.6
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    • pp.1199-1211
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    • 2014
  • The momentum flux and the sensible heat flux were measured with the scintillometers and ultrasonic anemometers at 6 sites of which surface characteristics like roughness length and zero-displacement are different each other. We estimated the momentum flux and the sensible heat flux based on the bulk transfer method with the drag coefficient and the heat transfer coefficient calculated from the temperature and wind speed at two heights. The variation of bulk transfer coefficients showed a remarkable difference depending on the atmospheric stability which is less influenced by the zero-displacement than the roughness length. The estimated sensible heat fluxes were in good agreement with those measured at 3 m, showing 23.7 $Wm^{-2}$ of the root mean square error that is less than 10% of its maximum. Since the estimated momentum flux is not only effected by drag coefficient but also by wind speed square, the determination of wind speed in the bulk transfer method is critical.

단위체 형상의 구조적 변화에 따른 오그제틱 회전 강체 구조의 기계적 특성에 대한 유한 요소 해석

  • Jo, Hyeon-Ho;Eom, Yun-Sik
    • Proceeding of EDISON Challenge
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    • 2017.03a
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    • pp.317-323
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    • 2017
  • Due to the unique characteristic of auxetic material, negative poisson's ratio, it has a variety of distinctive properties compared to conventional materials. Numerous researches have been conducted on the auxetic material in order to find out how to make auxetics. In this study, we analyzed triangular and rectangular patterned rotating rigid units using finite element method. Our purpose is to investigate the mechanical properties of the rotating rigid units and to show their auxetic behaviors. We studied the Poisson's ratio and the bulk modulus of the rotating rigid units depending on their unit cell sizes. The Poisson's ratio and the bulk modulus decreased as the number of unit cells increased. Also, when the geometry of the unit cell was changed, the tendency of the Poisson's ratio and the bulk modulus was also different from the previous case. The results of the Poisson's ratio and the bulk modulus referred that they were critically affected by the number of unit cells and the shape of unit cell.

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Incorporating mesh-insensitive structural stress into the fatigue assessment procedure of common structural rules for bulk carriers

  • Kim, Seong-Min;Kim, Myung-Hyun
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.7 no.1
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    • pp.10-24
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    • 2015
  • This study introduces a fatigue assessment procedure using mesh-insensitive structural stress method based on the Common Structural Rules for Bulk Carriers by considering important factors, such as mean stress and thickness effects. The fatigue assessment result of mesh-insensitive structural stress method have been compared with CSR procedure based on equivalent notch stress at major hot spot points in the area near the ballast hold for a 180 K bulk carrier. The possibility of implementing mesh-insensitive structural stress method in the fatigue assessment procedure for ship structures is discussed.

Laser Doppler Vibrometer using the Bulk Homodyne Interferometer (호모다인 간섭계를 이용한 레이저 진동 측정기의 개발)

  • 라종필;경용수;왕세명;김경석;박기환
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.397-402
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    • 2003
  • The FM demodulation method for a bulk homodyne laser interferometer is presented. The Doppler frequency that represents the surface velocity of a vibrating object is obtained by using the bulk homodyne laser interferometer, and converted to the voltage signal by using the proposed analogue FM demodulation circuit. The DC offsets of the interferent signals that are obtained from the bulk homodyne interferometer are eliminated by using a simple subtraction. The new method for compensation of the asymmetry of each channels is presented. The light power variation of the interferometer is normalized by using the Auto Gain Controller(AGC). The proposed FM demodulation algorithm is proved by the theoretical method, and validated by the experimental results. In experiments, the proposed FM demodulation algorithm is compared with the conventional demodulation methods.

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Fabrication of Bulk High-Tc Superconductor (벌크형 고온 초전도 합성)

  • Lee, Sang Heon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.34 no.5
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    • pp.333-336
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    • 2021
  • Oxide YBCO bulk superconductors are manufactured using the melt process. Because seed crystal growth method utilizes a slow-spreading layer-by-layer reaction, a long-term heat treatment is required to manufacture a single-crystal specimen of several cm. In this study, the melt process method was applied to compensate for the shortcomings of the seed crystal growth method. The thickness of the upper and lower pellets of the YBCO bulk was molded to 40 mm, and YBCO superconductor was produced by heat treatment. The measurement results of capture magnetism was in line with the literature. This results in a relationship that the higher the growth of Y211 particle in the YBCO, the higher the superconducting properties. We analyzed the YBCO superconductor, focusing on the Y2BaCuO5 particle distribution.

Optimization of the Lowry Method of Protein Precipitation from the H. influenzae Type b Conjugate Vaccine Using Deoxycholic Acid and Hydrochloric Acid

  • Kim, Hyun-Sung;Kim, Sang-Joon;Kim, Hui-Jung;Kim, Han-Uk;Ahn, Sang-Joem;Hur, Byung-Ki
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.11 no.3
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    • pp.215-222
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    • 2006
  • The Lowry method was used in this study to measure protein in Haemophilus influenzae type b (Hib) conjugate vaccines (polyribosylibitol phosphate-tetanus toxoid; PRP-TT) using deoxycholic acid (DOC) to induce protein precipitation. Trichloroacetic acid (TCA) did not induce precipitation adequately from the Hib conjugate bulk and the freeze-dried Hib conjugate product. Its yield was approximately 50%. The matrix structure of Hib conjugate inhibits precipitation by TCA. Although the Lowry method can be carried out without precipitation in Hib conjugate bulk when no residual impurities (adipic acid dihydrazide [ADH], 1-ethyl-3-(3-dimethylamino-propyl) carbodiimide-HCI [EDAC], phenol and cyanogens bromide [CNBr], etc.) are present, it cannot be used for Hib conjugate products that contain sucrose 8.5%, because 8.5% concentration of sucrose enhanced the protein concentration. DOC- and HCl-induced precipitation is an alternative method for evaluating the protein content of the Hib conjugate bulk and the Hib conjugate product. The precipitation was optimal with a final concentrate of 0.1% for DOC at $4^{\circ}C$ and pH 2. This Lowry method, using DOC/HCI precipitation to induce protein precipitation, was confirmed a consistent, reproducible, and valid test for proteins in Hib conjugate bulk and its freeze-dried product.

Effect of Air Flow on Chemical Properties of Cured Leaves in Bulk Curing Process (황색종 Bulk건조과정의 송풍량과 건조엽의 화학성분 특성)

  • 이철환;진정의
    • Journal of the Korean Society of Tobacco Science
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    • v.21 no.2
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    • pp.182-187
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    • 1999
  • A bulk curing experiment was carried out to evaluate the effect of air flow reduction in the bulk barn from color fixing stage in the chemical properties of cured leaves, The air flow was controlled by reducing air velocity of a blower from 0.3m/sec to 0.2m/sec using a boltage regulator(Slidac). The bulk curing before color fixing stage was processed in the conventional curing method. Reduction of air circulation in bulk barn did not affected so much on change of the contents of the main chemical components in cured leaved, such as nicotine, total sugar, total nitrogen, petroleum ether extract, and organic acids. Only a slight increase in essential oil contents, such as solanone, damascenone, damascone, $\beta$-ionone, and megastigmatrienone isomer, could be observed in leaves cured in the reduced air flow.

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NONCONVEX BULK TRANSPORTATION PROBLEM

  • Arora, S.R.;Ahuja, Anu
    • Management Science and Financial Engineering
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    • v.7 no.2
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    • pp.59-71
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    • 2001
  • In the present paper, we present method to solve a Fractional Bulk Transportation Problem(FBTP) in which the numerator is quadratic in nature and the denominator is linear. A related (FBTP) is formed whose feasible solutions are ranked to reach an optimal solution of the given problem. The method to find these feasible solutions makes use of parametric programming wherein a series of Ordinary Bulk Transportation Problems are solved by the usual methods.

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