• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.6
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• pp.1186-1191
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• 2011

Composition which was used as a white smoke grenade consists of Aluminium(Al), Hexachloroethane(HCE) and Zinc Oxide(ZnO), etc. there is a possibility of misfire due to long term storage and there are very few reports on the mechanism behind misfire. In this study, an experimental method known as accelerated degradation testing is used to investigate the chemical mechanism resulting in misfire. The mechanism of chemical change during long term storage was analyzed with XRD and FT-IR. Analysis results suggest that a part of HCE consisting of the white smoke grenade disappeared and the other part was combined into $ZnCl_2$, $AlCl_3$, as a recycled intermediate product under closed system.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.1
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• pp.48-54
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• 2023

Guided missiles are a one-shot system that finishes their purpose after being used once, and due to the long-term storage until launch, the storage reliability is calculated during development, and performance is maintained through periodic inspections until the life cycle arrives. However, the reliability standards applied in the development of guided missiles were established by analyzing data accumulated by the United States during long-term operation in the country, and since they are different from our environment, the 00 guided missiles that have been deployed in the armed forces for more than 10 years under the premise that there is a difference from actual reliability. As a result of verifying the appropriateness of the current inspection cycle by analyzing the actual reliability of the missile, the necessity of changing the inspection period was derived because it was higher than the predicted reliability. It is proposed to build and utilize a lifespan management system that can systematically collect all data such as shooting and maintenance results by classification, and to establish a reliable reliability standard based on the accumulated data.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.287-295
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• 1996

To fulfill the requirements for establishing processes of canning low-acid foods, canned tuna packed in cottonseed oil (CTCO) sterilized at $110^{\circ}C$ for varying $F_0-values$ was subjected to microbial, sensory and chemical analyses. The investigation included the long-term quality stability of those products stored at $5^{\circ}C,\;25^{\circ}C\;and\;50^{\circ}C$ for 120 days. Longer sterilization $(F_0>5.18min)$ caused no remarkable changes in pH, amino nitrogen content, TBA value, POV and sensory scores of the CTCOs during storage at all experimental temperatures. But the sterilizing with $Fe\leq5.18min$ resulted generally poor quality in all experimental analyses. Consequently, $F_0-value$ 6.0 min may be applicable to sterilization of CTCO for long-term storage stability.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.4
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• pp.228-232
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• 2015

The water supply galvanized steel pipes of apartment buildings in Bucheon city constructed with building permission before 1994 have many problems such as leaks, the water containing rust, and low water pressure due to corrosion. Therefore, this study aims to find a way to renew the water supply pipes under investigation through a survey. As a result, when replacing the galvanized steel pipe with the corrosion-resistant pipe, the water supply system should also be changed from the gravity tank system to the booster pump system and the hygienic water storage tank. It is necessary to redraft the long-term repair plan including the replacement of the water supply system. Also, it is necessary to save the allowance reserve according to the modified long-term repair plan.

• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.172-177
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• 2008

This study was carry out evaluation of long-term performance for the decentralized desalination system with the solar thermal system and the photovoltaic power system. First operating demonstration system was set up in Cheju in 2006. These system comprises the desalination unit with designed daily fresh water capacity of $2m^3$ and is supplied by a $120m^2$ evacuated tubular solar collector, a $6m^3$ heat storage tank, and a 5kW photovoltaic power generation supply the electricity for hydraulic pumps to move the working fluids. In a clear day more than 400W/$m^2$, the daily fresh water showed to produce more than about 500liter, and from January, 2007 to October, 2008 for 2 years, solar irradiance daily averaged was measured 370W/$m^2$, the daily fresh water yield showed that can be produced about 330liter.

• Journal of Korean Society of Archives and Records Management
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• v.7 no.1
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• pp.145-170
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• 2007

Unlike paper records, accessing electronic records needs to be supported by specific combination of hardware and software. The electronic records have longer life span than the storage media, hardware, software and the formats that were used for the production of such records. Because the quality of electronic record can become deteriorated as time goes on, we need to have appropriate mechanisms to secure the long-term preservation and access to the digital information at a certain point in the future. Based on this reality, this study proposes the functions and the development method of the format registry, which efficiently supports the preservation strategy such as migration and emulation, collecting and managing technical information elements. These elements consist of the foundation of the long-term preservation of the electronic records.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.4
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• pp.469-477
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• 2021

Safe storage of spent nuclear fuel in deep underground repositories necessitates an understanding of the long-term alteration of metal canisters and buffer materials. A small-scale laboratory alteration test was performed on metal (Cu or Fe) chips embedded in compacted bentonite blocks placed in anaerobic water for 1 year. Lactate, sulfate, and bacteria were separately added to the water to promote biochemical reactions in the system. The bentonite blocks immersed in the water were dismantled after 1 year, showing that their alteration was insignificant. However, the Cu chip exhibited some microscopic etch pits on its surface, wherein a slight sulfur component was detected. Overall, the Fe chip was more corroded than the Cu chip under the same conditions. The secondary phase of the Fe chip was locally found as carbonate materials, such as siderite (FeCO₃) and calcite ((Ca, Fe)CO₃). These secondary products can imply that the local carbonate occurrence on the Fe chip may be initiated and developed by an evolution (alteration) of bentonite and a diffusive provision of biogenic CO₂ gas. These laboratory scale results suggest that the actual long-term alteration of metal canisters/bentonite blocks in the engineered barrier could be possible by microbial activities.

• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.4
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• pp.5-11
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• 2011

The present study investigated the actual conditions of physical therapy rooms at long-term hospitals in Korea and conducted a comparative analysis to develop an efficient floor plan and facility improvement measures. 1. At hospitals surveyed, physical therapy services were used at a high frequency but they did not have enough space for rehab treatment and long paths of patient flow were found to make patient management inconvenient. Therefore, physical therapy units should be conveniently located both in terms of distance and direction so as to be accessible from patient rooms or wards. The space should be organized in a concentrated layout for efficiency of physical therapy, and floor planning for therapy units should ensure the best possible viewing angle to therapists. 2. With regard to the disease characteristics of patients, many physical therapy rooms were in difficult circumstances because of poor facilities, so they need to secure skilled personnel, supplement apparatuses and equipment and have rooms for functional recovery, hydrotherapy and operation treatment. In addition, each of the curtained or partitioned areas for treatment should be set up with consideration for the amount of space taken up by medical equipment. The area under each bed should be designed for patient convenience so that it can be used as storage space for patient's belongings and shoes. 3. Patients complained about the lack of physical therapy space, resting places or exercise areas and demanded the expansion of rehab programs and facilities. Physical therapy facilities need to be improved for patient privacy and effective natural ventilation. 4. At most of the long-term hospitals surveyed, physical therapy units were found to have small areas and treatment equipment and devices were insufficient compared to the number of patients. Therefore, it is required to secure more space (at least 138.24 sq. meters per 100 beds) and improve facilities for better physical therapy services.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.224-231
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• 2011

Effects of 1-methylcyclopropene (1-MCP) treatment and controlled atmosphere (CA) storage was analyzed for the export quality of 'Fuji' apples after 8-month storage. Apples were harvested from two orchards located in different regions at relatively late stage of maturity for long-term storage. Fruit were treated with 1 ${\mu}L{\cdot}L^{-1}$ 1-MCP and then stored in $0^{\circ}C$ air or CA with 1.5 kPa $O_2$ and < 1.0 kPa $CO_2$ for 8 months. To simulate poststorage export process such as 2-week refrigerated container shipment plus 7-day local distribution, fruit were put in $0^{\circ}C$ air storage for additional two weeks and then on the shelf for 7 days at $20^{\circ}C$. Both the 1-MCP treatment and CA storage reduced respiration and ethylene evolution after storage and shipping simulation, and successfully maintained titratable acidity and flesh firmness even after the export process. In 'Fuji' apples harvested after adequate stage of maturity for long-term storage, however, 1-MCP treatment alone seemed not to be satisfactory for the maintenance of sensorial fruit texture for export market. CA storage or 1-MCP treatment/CA storage combination program should be applied for lately harvested 'Fuji' apples exported after eight months storage.

• Food Science and Preservation
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• v.3 no.2
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• pp.105-111
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• 1996

The conditions of cold stroage of Citrus unshiu Marc. var. okitsu produced in Cheju were investigated. The changes of peel moisture contents soluble solids, total sugar, vitamin C and density were slightly occured, and decay ratio was below 20% on keeping freshness relatively till late of March during cold storage. After thats decayed citrus fruits were increased gradually mainly from cold injury with lower temperature and high humidity. The loss of fruit weight, decrease of fruit hardness, and decrease of acid content were occured gradually during cold stroage. Because of the difficulty of long term storage for Citrus unshiu, the conditions and periods of cold storage would be determined after considering the physicochemical properties of fruits every year.