• Title, Summary, Keyword: high hydrostatic pressure

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Effects of High Hydrostatic Pressure and Gamma Irradiation on Quality and Microbiological Changes of Kochujang-Gulbi. (고추장굴비의 품질과 저장성에 미치는 초고압처리와 감마선 조사 효과)

  • Kang, Seong-Gook;Park, Nan-Hee;Ko, Do-Ock;Li, Jing-Lei;Kim, Bo-Sub;Park, Yang-Kyun
    • Korean Journal of Food Preservation
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    • v.18 no.1
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    • pp.1-6
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    • 2011
  • Kochujang-gulbi, a Korean traditional food, was prepared with kochujang and freeze-dried gulbi slices. Kochujang-gulbi was treated with high hydrostatic pressure (200, 400 and 600 MPa) and gamma-irradiation (7, 10, 20 and 30 KGy) to improve its quality and shelf-life. The pH of high hydrostatic pressure and gamma-irradiation treated kochujang-gulbi samples did not significantly different compared to that of control. However, Hunter L value slightly increased, and Hunter a and b values decreased by high hydrostatic pressure and gamma-irradiation treatment. During storage, the pH and color of high hydrostatic pressure and gamma-irradiation treated kochujang-gulbi samples did not significantly changed. The VBN and TBA level decreased by the increase treatment of high hydrostatic pressure and then slowely increased during storage. The VBN and TBA level of kochujang-gulbi samples treated by the strong gamma ray emission slowely increased during storage. In particular, gamma-irradiation treatment was very effective to sterilize microorganisms when compared to that of high hydrostatic pressure in kochujang-gulbi products. In addition, the high hydrostatic pressure and gamma-irradiation treated kochujang-gulbi samples shown significantly lower total viable cell number than control for the 20 days of storage at room temperature with retort pouch packaging.

A Study on the Characteristics of the Hydrostatic Bearing by the Variation of the Orifice in Hydraulic Piston Motor (유압 피스톤 모터의 오리피스 변화에 따른 정압베어링의 특성에 관한 연구)

  • Kim, K.M.;Lee, Y.B.;Kim, T.S.
    • Transactions of The Korea Fluid Power Systems Society
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    • v.7 no.3
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    • pp.7-12
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    • 2010
  • In the case of hydraulic piston motor, hydrostatic bearing is designed to be adapted the hydrostatic bearing for the relative lubrication in the structural design. It's available to make it highly efficient and that's why it's widely used. The thing which largely influence the high pressure, the high efficiency, and the life is the hydrostatic bearing between a shoe and a swash plate. In this study, with the most general "hydrostatic bearing shoe" that has one recess as the subject of this research, I designed and made the 4 kind of piston shoe that have different orifice diameter each other, and studied the features of the hydrostatic bearing by observing the change of the leakage flow rate, the torque and the volumetric efficiency through experiments on the changes of the pressure & the speed of the revolution. As a result, the bigger diameter of the orifice, the less torque. And with an increase of the orifice diameter under the high pressure, the leakage flow rate decreased remarkably. Also it was observed the leakage flow rate increased linearly according to the increase of the supply pressure.

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Inactivation of Microorganisms and Browning Enzymes in Angelica keiskei Juice Using High Hydrostatic Pressure (초고압을 이용한 신선초 녹즙의 살균 및 갈색화 효소의 불활성화)

  • Lee, Dong-Un;Park, Ji-Yong;Lee, Yun-Bom;Yeo, Ick-Hyun
    • Korean Journal of Food Science and Technology
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    • v.27 no.6
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    • pp.991-996
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    • 1995
  • Effects of high hydrostatic pressure on microorganisms and browning enzymes in Angelica keiskei juice were investigated using response surface methodology. The optimum process condition for maximum reduction of total aerobes was $5700\;kg_f/cm^2$ (558.6 MPa) pressure and 7.16 min process time, and 3.44 log cycle reduction of total aerobes was predicted at the optimum condition. E. coli, initially $8.8{\times}10^3\;CFU/ml$, was completely inactivated by high hydrostatic pressure at all process conditions ($3800{\sim}6700\;kg_f/cm^2\;pressure;\;3{\sim}17\;min\;process\;time$). Polyphenol oxidase and peroxidase were partly inactivated by the high hydrostatic pressure. It was also indicated that inactivation of microorganisms and browning enzymes by hydrostatic pressure is dependent on pressure rather than process time.

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Application of Biological industry using High Hydrostatic Pressure (HHP) system (초고압 시스템을 이용한 생물 산업의 적용)

  • Lee, Kwang-Jin;Choi, Sun-Do
    • KSBB Journal
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    • v.23 no.5
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    • pp.362-368
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    • 2008
  • High Hydrostatic Pressure assisted (HHP) process enhancement for food and allied industries are reported in this paper review. Recently, considerable research has been devoted to the improvement of mild thermal processing techniques and to the development of alternative mild processing technologies. HHP assisted can enhance existing extraction, processes and enable new commercial extraction opportunities and processes. New HHP processing approaches have been proposed, including, the potential for modification of plant cell material to provide improved bioavailability of micro nutrients while retaining the natural-like quality, simultaneous extraction. Therefore, High Hydrostatic Pressure assisted (HHP) technologies could have a strong presence in the future of the biotechnology industry.

Memory Enhancing Effect of Codonopsis lanceolata by High Hydrostatic Pressure Process and Fermentation (초고압 발효 더덕 추출물의 인지능력 개선 효과)

  • Weon, Jin Bae;Lee, Bohyoung;Yun, Bo-Ra;Lee, Jiwoo;Lee, Hyeon Yong;Park, Dong-Sik;Chung, Hee-Chul;Chung, Jae Youn;Ma, Choong Je
    • Korean Journal of Pharmacognosy
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    • v.44 no.1
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    • pp.41-46
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    • 2013
  • Alzheimer's disease (AD), most common form of dementia is characterized that memory deficit and loss of cognitive function. The Codonopsis lanceolata (C.lanceolata) was treated by high hydrostatic pressure process and fermentation. This study was evaluated cognitive enhancing effect C.lanceolata extract by high hydrostatic pressure process and fermentation and compared with common C.lanceolata extract using Morris water maze and passive avoidance test. And their neuroprotective effect on glutamate induced oxidative stress in HT22 cell was investigated by MTT assay. High hydrostatic pressure process and fermented C.lanceolata extract (HFCE) and common C.lanceolata extract (CCE) (100 and 300 mg/kg) were administered to mice. Results showed HFCE enhanced cognitive function than CCE as shown by decrease in escape latency time. HFCE increased the latency time of the passive avoidance test compared to CCE. Furthermore, HFCE showed significant neuroprotective effect against glutamate cytotoxicity in HT22 cells. These results indicate that high hydrostatic pressure process and fermented more improve spatial cognitive ability of C. laanceolata.

The Effect of High Hydrostatic Pressure Treatment on the Preservability and the Immunological Activity of Bovine Colostrum

  • Masuda, T.;Rehinarudo, H.Y.;Suzuki, K.;Sakai, T.;Morichi, T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.9
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    • pp.1323-1328
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    • 2000
  • Bovine colostrum, which contains a large quantity of immunoglobulins, is indispensable for newborn animals. The establishment of a new procedure for preserving colostrum without losing the immunological activity is significant. We examined the effect of high hydrostatic pressure treatment (100~500 MPa) on the preservability and the immunochemical activity of bovine colostrum. When high hydrostatic pressure treatment was 300 MPa or more, the increase of the total viable count, coliforms and psychrotrophic gram-negative bacteria was suppressed effectively. In particular, the number of coliforms in colostrum treated at 300 MPa or more hardly increased for 35 days at $4{^{\circ}C}$. At 400 MPa or more, both gelling of the colostrum and denaturation of immunoglobulins were observed. However, if the pressure was 300 MPa, immunoglobulins were scarcely influenced and the neutralizing titers against the bovine coronavirus did not decrease. Therefore, it was suggested that 300 MPa was the best pressure for good preservability of colostrum without reducing the immunochemical response.

A Study on the Development of Hydrostatic High Speed Spindle for Grinding Machine (고속 연삭기용 유정압 스핀들 개발에 관한 연구)

  • Kim, Jeong-Suk;Cho, Yong-Kwon;Park, Jin-Hyo;Moon, Hong-Man
    • Journal of The Korean Society of Manufacturing Technology Engineers
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    • v.20 no.1
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    • pp.96-100
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    • 2011
  • The hydrostatic bearings have a relatively small run-out comparing to its shape error by fluid film effect in hydrostatic state as like pneumatic bearing and have a high stiffness, load capacity and damping characteristics. As there is no maintenance and semipermanent in these bearing type, it has been usually adopted as main spindle bearing for grinding machine. In this thesis, to develop hydrostatic bearing for high speed spindle, the cooler setting temperature, bearing clearance and nozzle pressure of belt-driven hydrostatic bearing are investigated. The bearing temperature is decreased, as the cooler setting temperature is lower, nozzle pressure is higher and bearing clearance is wider. The front temperature of bearing is nearly $8^{\circ}C$ higher than the rear one up to 13,000 rpm of spindle revolution. The thermal deflection of X-axis is ${\pm}16\;{\mu}m$ in range of 12,000 rpm-13,000 rpm. Therefore, it is conformed that the built-in motor hydrostatic bearing can be used to high speed spindle.

A Comparison of Standard Methods for Evaluating the Water Resistance of Shell Fabrics

  • Kwon, Myoung-Sook;Nam, Youn-Ja
    • The International Journal of Costume Culture
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    • v.4 no.3
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    • pp.241-248
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    • 2001
  • Re water resistance of shell fabrics intended for we in outdoor apparel was measured using three different standard test methods, ASTM D 751, hydrostatic resistance, procedure A(Mullen test -- with and without a fabric support) and Procedure B (Hydrostatic head test). A database of information on their water resistance performance was created. The data collected with different methods were correlated and the advantages and disadvantages of each method were compared. The Mullen test with a support appears to give higher and more favorable water resistance values on shell fabrics preventing fabric rupture during the test. The hydrostatic head test gave lower hydrostatic pressure values than those measured on the two Mullen tests. The Mullen test is recommended for testing the water resistance of fabrics that high a relatively high water resistance because the Mullen tester applies a wide range of pressure. The hydrostatic head test is recommended for testing the fabrics that have relatively low water resistance. The area of the fabric sample that is in contact with the water is smaller in the Mullen test, so higher pressure levels can be reached and more samples should probably be tested to get a representative value for each fabric types. Furthermore, the hydrostatic head test was deemed more repeatable than the Mullen tests in his study.

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Pressure Ripple Reduction in Hydrostatic Transmissions by Using a Hydraulic Filter (맥동흡수용 유압필터에 의한 유압전동장치의 압력맥동 감쇠)

  • 김도태
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.11 no.3
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    • pp.33-38
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    • 2002
  • This paper deals with pressure ripple attenuation far separated-type Hydrostatic Transmission (HST) consisting ova variable axial piston pump connected in an open loop to a fried displacement axial piston motor. Pressure ripples in HST is major source of vibration which can lead to fatigue failure of components and cause noise. In order to reduce the pressure ripple, an annular tube tripe hydraulic filter is proposed to attenuate pressure ripples with the high frequencies components to achieve better noise reduction in HST. The basic principle of a hydraulic filter is allied to propagation of pressure wave, reflection, absorption in cross section of discontinuity and resonance in the hydraulic pipeline. It is experimentally shown that the hydraulic filter attenuates about 30∼40dB of pressure ripple with high frequencies. These results will assist in modeling and design of noise reduction in hydraulic control systems, and provide a means of designing a quieter HST.

The Design, Structural Analysis and High Pressure Chamber Test of a Thick Pressure Cylinder for 2000 m Water Depth (수심 2000m 용 두꺼운 내압용기의 설계, 구조해석과 내압시험)

  • Choi, Hyeuk-Jin;Lee, Jae-Hwan;Kim, Jin-Min;Lee, Seung-Guk;Maring, Kothilngam
    • Journal of the Society of Naval Architects of Korea
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    • v.53 no.2
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    • pp.144-153
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    • 2016
  • This paper aims to demonstrate the design, structure analysis, and hydrostatic pressure test of the cylinder used in 2000m water depth. The cylinder was designed in accordance with ASME pressure vessel design rule. The 1.5 times safety factor required by the general rule was applied to the design of the cylinder, because ASME rule is so excessive that it is not proper to apply to the hydrostatic pressure test. The finite element analysis was conducted for the cylinder. The cylinder was produced according to the design. The hydrostatic pressure test was conducted at the hyperbaric chamber in KRISO. The results of finite element analysis(FEM) and those of the hydrostatic pressure test were almost the same, which showed that the design was exact and reliable.