• Title/Summary/Keyword: storage safety

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Effects of Residual Phosphorus Content on color Reversion and Storage Stability of Corn Germ Oil (잔류 인함량이 옥배유의 변색및 저장안정성에 미치는 영향)

  • 김종승;이근보;이미숙
    • Journal of Food Hygiene and Safety
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    • v.12 no.2
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    • pp.107-110
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    • 1997
  • To examine the effects of residual phosphorus content on color reversion and storage stability of corn germ oil, the changes of Lovibond total color and stability of oxidation were determined according to the different storage periods at room and incubating temperature, respectively. The residual phosphorus content and storage temperature had the synergistic effect on color reversion during short time storage. The extent of color change was the greatest when oils were stored for 1.0∼1.5 years at room temperature and thereafter gradually tended to reverse color reversion. It is supposed that the double bonds of carotenoids in oils were oxidized and then turned to the volatiles such as epoxide, ionone, and etc. In contrast, the residual phosphorus content increased oxidation stability of oils. The residual phosphorus content was closely correlated with the color reversion and storage stability, respectively.

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A Study on Behavior of Rectangular Liquid Storage Structures (직사각형 단면을 갖는 유체 저장 구조물의 거동에 관한 연구)

  • 박장호
    • Journal of the Korean Society of Safety
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    • v.18 no.1
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    • pp.101-107
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    • 2003
  • Dynamic behavior of flexible rectangular liquid storage structures is analysed by the developed method. The rectangular liquid storage structures are assumed to be fixed to the ground and a moving coordinate system is used. The irrotational motion of invicid and incompressible ideal fluid is represented by two analytic solutions. One is the solution of the fluid motion in the rigid rectangular liquid storage structure due to ground motions and the other is the solution of the fluid motion by the motion of the wall in the flexible rectangular liquid storage structure. The motion of structure is modeled by finite elements. The fluid-structure interaction effect is reflected into the coupled equation of motion as added fluid mass matrix. The free surface sloshing motion and hydrodynamic pressure acting on the wall in the flexible rectangular liquid storage structure due to the horizontal ground motion are obtained by the developed method and verified.

The Development of Compressive Strength Estimation Equation for LNG Storage Tank using Rebound Hardness Method (반발경도법을 이용한 LNG 저장탱크 콘크리트의 압축강도 추정식 개발)

  • Kim, Jung-Hoon;Kim, Young-Gu;Jo, Young-Do
    • Journal of the Korean Institute of Gas
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    • v.21 no.3
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    • pp.26-32
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    • 2017
  • Outer tank concretes of LNG storage tank are composed of prestressed concrete structures that act as a protective wall. The danger such as the collapse of structures will exist if concrete structures is not secured due to the deterioration. Concrete compressive strength directly related to the safety of structures can be predicted by using estimation equation of compressive strength through rebound hardness test and ultrasonic wave velocity method. But, there is no the estimation equation of LNG storage tank for a relation between NDT data and real strength. In this study, to obtain more accurate real strengths for LNG storage tank, core specimens were sampled from walls of pilot LNG storage tank. The rebound hardness test of general NDT for concrete structures was carried out at each 3 positions for the four areas. The compressive strength estimation equation of LNG storage tank was developed by using the data for rebound hardness test of pilot LNG storage tank and compressive strength test of sampled concrete cores.

A Study on the Design Safety of Type III High-Pressure Hydrogen Storage Vessel (Type III 고압수소저장용기의 설계 안전성 연구)

  • Park, Woo Rim;Jeon, Sang Koo;Kim, Song Mi;Kwon, Oh Heon
    • Journal of the Korean Society of Safety
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    • v.34 no.5
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    • pp.7-14
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    • 2019
  • The type III vessel, which is used to store high-pressure hydrogen gas, is made by wrapping the vessel's liner with carbon fiber composite materials for strength performance and lightening. The liner seals the internal gas and the composite resists the internal pressure. The properties of the fiber composite material depends on the angle and thickness of the fiber. Thus, engineers should consider these various design variables. However, it significantly increases the design cost due to the trial and error under designing based on experience or experiments. And, for aluminum liners, fatigue loads due to using and charging could give a huge impact on the performance of the structure. However, fatigue failure does not necessarily occur in the position under the highest load in use. Therefore, for hydrogen storage vessel, fatigue evaluation according to design patterns is essential because stress distribution varies depend on composite layer patterns. This study performed an optimization analysis and evaluated a high-pressure hydrogen storage vessel to minimize these trial and error and improve the reliability of the structure, while simultaneously conducting fatigue assessment of all patterns derived from the optimization analysis process. The results of this study are thought to be useful in the strength improvement and life design of composite reinforced high-pressure storage vessels.

A Study on the Safety of Small LPG Storage Tanks at External Fires (외부화재시 LPG 소형저장탱크의 안전성에 관한 연구)

  • Yim, Ji-Pyo;Ma, Byung-Chol;Chung, Chang-Bock
    • Journal of the Korean Society of Safety
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    • v.30 no.4
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    • pp.64-72
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    • 2015
  • The purpose of this study is to study the safety of a small LPG storage tank with a capacity less than 3 ton when it is exposed to an external fire. First, simulation studies were carried out using ASPEN Plus and PHAST to demonstrate that overpressurization in the tank can be relieved by discharging the LPG through an adequately sized safety valve, but the release may lead to the secondary risk of fire and explosion around the tank. Next, the temporal variations of the temperatures of the lading and tank wall were obtained using AFFTAC, which showed that the tank wall adjacent to the vapor space could be overheated in about 11 min to such a point that the weakened strength might cause a rupture of the tank and subsequent BLEVE. The consequences of the BLEVE were estimated using PHAST. Finally, several practical measures for preventing the hazards of overheating were suggested, including an anti-explosion device, sprinkling system, insulation, heat-proof coating, and enhanced safety factor for tank fabrication. The effectiveness of these measures were examined by simulations using AFFTAC and ASPEN Plus.

Study on Filling Capacity of Self-Consolidating Concrete for Modular LNG Storage Tank (모듈형 LNG 저장탱크용 자기 충전 콘크리트의 충전 성능평가 실용화 연구)

  • Lee, Dong Kyu;Lee, Keon Woo;Choi, Myoung Sung
    • Journal of the Korean Society of Safety
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    • v.33 no.6
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    • pp.50-57
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    • 2018
  • The purpose of this study is to evaluate the practical application of the self consolidating concrete for the steel concrete pannel (SCP) in module LNG storage tank proposed in the previous research. We evaluated the physical properties and filling performance of developed concrete for the SCP module. First, a slump flow test was conducted to evaluate the performance of the proposed guidelines for the filling test. As a result, all of the concrete used showed satisfactory performance. Based on the results of the previous study, it was found that the reliability of the required time measured by the $T_{500}$ test and the rheometer results measured before and after pumping was 0.94 which means the separation and blocking should not occur. The L-box test and the U-box test were conducted before and after pumping. All of the guidelines suggested showed satisfactory performance. SCP module for LNG storage tanks was fabricated on actual size scale to evaluate the practical application at the final site. As a result, it was confirmed that satisfactory filling performance was obtained in all the specimens.

Review of Spent Nuclear Fuel Dry Storage Demonstration Programs in US (미국의 사용후핵연료 건식저장 실증연구의 과거와 현재)

  • Lee, Sanghoon;Yook, Daesik
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.2
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    • pp.135-149
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    • 2017
  • Demonstration programs for spent nuclear fuel dry storage have been carried out to produce important and confirmatory data to support safety of dry storage systems and integrity of spent nuclear fuel stored in dry condition. The US initiated the dry storage of spent nuclear fuel and has strict and explicit regulatory stipulations on the integrity of spent nuclear fuel in dry storage. The US has carried out several notable demonstration programs for the initiation and license extension of dry storage. At the very early stage of dry storage, the demonstration programs were focused on proof of the safety of dry storage systems and a demonstration project called the dry cask storage characterization project was performed for the license extension of low burn-up fuel dry storage. Currently, a demonstration program for the license extension of high burn-up fuel dry storage is under way and is expected to continue for at least 10 years. Korea has not yet begun the dry storage of PWR fuel and the US programs can be a good reference and can provide lessons to safely begin and operate dry storage in Korea. In this paper, past and current demonstration programs of the US are analyzed and several recommendations are provided for demonstration programs for the dry storage of spent nuclear fuel in Korea.

Design Study for the Improvement of Storage Space in the Problem of Domestic Ambulances (국내 구급차 내 수납공간의 문제점과 개선방안을 위한 디자인 연구)

  • Shin, Dong-Min;Kim, Seung-Yong;Hann, Boong-Gi;Han, Yong-Taek
    • Journal of the Korean Society of Safety
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    • v.30 no.1
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    • pp.79-86
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    • 2015
  • This research proposed a design direction for the ambulance interior storage space based on the placement and access to the equipment to facilitate an emergency medical practice taking into account the safety and efficiency by the emergency medical technician ergonomic factors. Therefore, through a field survey for the current derivation of the storage space problem 'placement', 'enable', 'management' like these three items resulting clarity, accessibility, simplicity and functionality of the four functional elements by targeting ambulances in operation in this country. First, there is a need to improve standardized of cabinet sizes fit to loaded meet emergency equipment standards. Currently, the equipment designed to use a simple storage cabinet has had problems in the usability. Second, it must be located in the continuous exposure in progress to the user's traffic line. Third, the problem was the insufficient function of the cabinet to ensure the safety of patients by paramedics from the emergency rescue equipment and due to the leaning of the ambulance driving. Besides, it was pointed out that in addition to the proposed alternatives, including the agenda, states that safety belt replacement equipment, emergency personnel and patients with the handle of a guardian for the efficient use storage space within the 119 ambulance. However, in the present study suggest that there is a state proceeds mainly limited usability in the field, having been installed.

Appropriate Distribution Temperature for the Quality of Unwashed Eggs Inoculated with Salmonella Enteritidis onto Shells (Salmonella Enteritidis가 접종된 비세척 계란의 품질 유지를 위한 적절 유통온도)

  • Ji-Hoon An;Hee-Seok Lee
    • Journal of Food Hygiene and Safety
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    • v.38 no.5
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    • pp.332-337
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    • 2023
  • This study aimed to assess the effect of temperature alterations on the preservation of egg quality and determine suitable temperature management practices for unwashed eggs contaminated with Salmonella Enteritidis on their shells in an actual distribution environment. Unwashed eggs inoculated with Salmonella Enteritidis were stored for 7 d under six different conditions, constant temperature storage at 25℃ and five different temperature-changing storage conditions. For the temperature-changing conditions, the eggs were initially stored at 25℃, and then the temperature was changed to either 10 or 35℃. The indicators of egg quality, air cell height, weight loss, and specific gravity were preserved in the initial measurements when the storage temperature was lowered from 25 to 10℃ from day 3 to 4 after inoculation with Salmonella Enteritidis. In addition, the thick albumen ratio did not show significant alteration caused by the storage conditions when compared with that of fresh eggs. These findings indicate that lowering the storage temperature from 25 to 10℃ is appropriate for the safety management of unwashed eggs during actual distribution.

Quality Changes During Storage of Cook-chilled Soybean Sprouts

  • Koo, Kyoung-Mo;Kim, Hyoun-Wook;Lee, Dong-Sun;Lyu, Eun-Soon;Paik, Hyun-Dong
    • Food Science and Biotechnology
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    • v.17 no.3
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    • pp.540-546
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    • 2008
  • Sous vide and packaged cook-chilled soybean sprouts were evaluated for physicochemical quality changes and microbial safety during storage for the purposes of shelf-life extension and industrial application. The physicochemical changes assessed were color, texture, and ascorbic acid concentration. The quality of soybean sprouts became worse with increased periods of storage and better in storage temperature of $3^{\circ}C$ more than in $10^{\circ}C$. The concentration of aerobic bacteria decreased from $2.1{\times}10^8$ to $6.0{\times}10^2\;CFU/g$ after pasteurization, but increased during storage. These bacteria are the same shape as anaerobic and hsychrophilic bacteria, but none of these other organisms were detected after heat treatment. The physicochemical qualities of soybean sprouts and microbial safety were better for products stored at $3^{\circ}C$ than at $10^{\circ}C$. In the case of short storage periods, heat treatment at $70^{\circ}C$ for 2 min was most effective for quality and microbial safety.