• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.5
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• pp.901-909
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• 2021

Since mobile devices have limited computational resources, it tends to use the cloud to compute or store data. As real-time becomes more important due to 5G, many studies have been conducted on edge clouds that computes at locations closer to users than central clouds. The farther the user's physical distance from the edge cloud connected to base station is, the slower the network transmits. So applications should be migrated and re-run to nearby edge cloud for smooth service use. We run applications in docker containers, which is independent of the host operating system and has a relatively light images size compared to the virtual machine. Existing migration studies have been experimented by using network simulators. It uses fixed values, so it is different from the results in the real-world environment. In addition, the method of migrating images through shared storage was used, which poses a risk of packet content exposure. In this paper, Containers are migrated with Secure CoPy(SCP) method, a data encryption transmission, by establishing an edge computing environment in a real-world environment. It compares migration time with Network File System, one of the shared storage methods, and analyzes network packets to verify safety.

• Composites Research
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• v.36 no.6
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• pp.435-440
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• 2023

This study aimed to enhance the thermal conductivity of B₄C/Al composite materials, commonly used in transport/storage containers for spent nuclear fuel, by incorporating both boron carbide (B₄C) and cubic boron nitride(cBN) as reinforcing agents in an aluminum (Al) matrix. The composite materials were successfully manufactured through a stir casting process and practical neutron-absorbing materials were obtained by rolling the fabricated composite ingot. The evaluation of the thermal conductivity of the fabricated composites was carried out because thermal conductivity is critical for neutron absorbing materials. The thermal conductivity measurement results indicated an approximately 3% increase in thermal conductivity under the same volume fraction when compared to composite materials using only B₄C particles. Through neutron absorption cross-sectional area calculations, it was confirmed that the neutron absorption capability decreased to a negligible level. Based on the findings of this study, new design approaches for neutron absorption materials are proposed, contributing to the development of high-performance transport/storage containers.

• Tribology and Lubricants
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• v.34 no.5
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• pp.197-207
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• 2018

Thermal deterioration of fuel due to long-term storage influences engine performance and causes malfunctions. Fuel stability is usually evaluated via heat resistance and thermal stability during a brief heat shock at high temperature; storage stability in this scenario means that there is very little change in the quality of the fuel during long-term storage. In addition, rubber-based products such as oil seals, O-rings, and rubber hoses can influence the quality of the fuel. When these rubber products are in contact with fuel, they can swell, mechanically weaken, and occasionally crack, thus leaking low molar weight rubber and additives including plasticizer and antioxidant into the fuel to degrade its properties and shorten its useful lifetime. This study determines the thermal stabilities of three kinds of synthetic fuels by evaluating their low temperature kinematic viscosities, chemical composition changes via GC analyses, gross heat of combustion, and color changes. We evaluate the compression set of O-rings by immersing one NBR and two FKM rubber O-rings in the three synthetic fuel samples in airtight containers at variable storage temperatures for six months; from this, we estimate the lifetimes of the O-rings using the Power law model. There were very little changes in the chemical compositions and gross heat of combustion after six months of the experiment. The lifetimes are thus dependent on the materials of the rubber products, and in particular, the FKM O-ring was calculated to have a theoretical lifetime of 200 to 5,700 years. These results indicate that the synthetic fuels maintain their physical properties even after long-term storage at high temperatures, and the FKM O-ring is suitable for long-term sealing of these fuels.

• Korean Journal of Plant Resources
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• v.22 no.2
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• pp.136-144
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• 2009

Germination tests on 3 species that have potential for use as sprout vegetables, such as Coreopsis tinctoria, Saussurea pulchella, and Matricaria recutica, were conducted for 20 days under different temperatures of $15{\sim}30^{\circ}C$, and conditions of light and dark. C. tinctoria showed germination of 83% under $15^{\circ}C$ and dark condition after 4 days, S. pulchella 51.7% under $25^{\circ}C$ and light condition after 20 days, and M. recutica 90.3% under $25^{\circ}C$ and dark condition after 4 days. To investigate optimum plantlet size before greening treatment, seeds germinated were allowed to grow under darkness. The optimum growth of C. tinctoria was obtained under $30^{\circ}C$ after 5 days, S. pulchella under $25^{\circ}C$ after 6 days, and M. recutica under $20^{\circ}C$ after 6 days. Greening treatment resulted in diminished longitudinal growth, but C. tinctoria and S. pulchella showed more vigorous latitudinal growth. Days required before marketing as sprout vegetables were different according to species - Three days of greening was good for C. tinctoria, 2 for S. pulchella, no greening for M. recutica. Generally, tightly sealed containers for minimum water loss were recommended for storage of sprout vegetables after harvest. However, storage methods for each species were different depending on various factors like temperature of storage, presence of ventilation holes of storage packages and forms of marketing. More detailed research for above 3 species is proposed.

• The Journal of the Korea Contents Association
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• v.7 no.10
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• pp.157-164
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• 2007

Human made a vessel which was made naturally to store something being hunted and picked, which was a great invention.(n modern times, society changed and development of science gave us convenience in making a vessel and various kinds of store instruments which was made of pure natural material), They have built the house which became to be a part of nature, and studied a method of storing food to eat for four seasons, then displayed a storage house and storage containers everywhere of the house. Now Korean has the custody of kimchi in refrigerator at every house. With hot wind of well-being, Korean food is becoming to be globalized, according to this the world shows concern seriously about the pottery This study have three purposes, the first. checking documents about the development history of pottery which is a kind of ceramic, and then the second, through an scientific experiment, with studying characteristic of pottery being built by the wisdom of ancestors, informing the merit of pottery and necessity to the world, and futhermore, the third, working up the development of close environmental vessels putting to use the characteristic of pottery.

• Nuclear Engineering and Technology
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• v.53 no.12
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• pp.4137-4141
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• 2021

As NPPs continue to operate, liquid waste continues to be generated, and containers are needed to store and transport them at low cost and high capacity. To transport and store liquid phase very low-level radioactive waste (VLLW), a container is designed by considering related regulations. The design was constructed based on the existing container design, which easily transports and stores liquid waste. The radiation shielding calculation was performed according to the composition change of barium sulfate (BaSO₄) using the Monte Carlo N-Particle (MCNP) code. High-density polyethylene (HDPE) without mixing the additional BaSO₄, represented the maximum dose of 1.03 mSv/hr (<2 mSv/hr) and 0.048 mSv/hr (<0.1 mSv/hr) at the surface of the inner container and at 2 m away from the surface, respectively, for a 10 Bq/g of ⁶⁰Co source. It was confirmed that the dose from the inner container with the VLLW content satisfied the domestic dose standard both on the surface of the container and 2 m from the surface. Although it satisfies the dose standard without adding BaSO₄, a shielding material, the inner container was designed with BaSO₄ added to increase radiation safety.

• Journal of the Korean Institute of Gas
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• v.26 no.3
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• pp.38-44
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• 2022

As the supply of hydrogen charging stations for hydrogen supply accelerates due to the hydrogen economy revitalization policy, the risk of accidents is also increasing. Since most hydrogen explosion accidents lead to major accidents, it is very important to secure safety when using hydrogen energy. In order to utilize hydrogen energy, it is essential to secure the safety of hydrogen storage containers used for production, storage, and transportation of liquid hydrogen. In this paper, in order to evaluate the structural safety of a hydrogen-filled pressure vessel, the behavioral characteristics of gas pressure were analyzed by finite element analysis. SA-372 Grade J / Class 70 was used for the material of the pressure vessel, and a hexahedral mesh was applied in the analysis model considering only the 1/4 shape because the pressure vessel is axisymmetric. A finite element analysis was performed at the maximum pressure using a hydrogen gas pressure vessel, and the von Mises stress, deformation, and strain energy density of the vessel were observed.

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4146-4158
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• 2022

Ultra-high performance concrete (UHPC) has been widely utilized in military and civil protective structures to resist intensive loadings attributed to its excellent properties, e.g., high tensile/compressive strength, high dynamic toughness and impact resistance. At present, aiming to improve the defects of the traditional vertical concrete cask (VCC), i.e., the external storage facility of spent fuel, with normal strength concrete (NSC) shield, e.g., heavy weight and difficult to fabricate/transform, the feasibility of UHPC applied in the shield of VCC is numerically examined considering its high radiation and corrosion resistance. Firstly, the finite element (FE) analyses approach and material model parameters of NSC and UHPC are verified based on the 1/3 scaled VCC tip-over test and drop hammer test on UHPC members, respectively. Then, the refined FE model of prototypical VCC is established and utilized to examine its dynamic behaviors and damage distribution in accidental tip-over and end-drop events, in which the various influential factors, e.g., UHPC shield thickness, concrete ground thickness, and sealing methods of steel container are considered. In conclusion, by quantitatively evaluating the safety of VCC in terms of the shield damage and vibrations, it is found that adopting the 300 mm-thick UHPC shield instead of the conventional 650 mm-thick NSC shield can reduce about 1/3 of the total weight of VCC, i.e., about 50 t, and 37% floor space, as well as guarantee the structural integrity of VCC during the accidental drop simultaneously. Besides, based on the parametric analyses, the thickness of concrete ground in the VCC storage site is recommended as less than 500 mm, and the welded connection is recommended for the sealing method of steel containers.

• Food Science and Preservation
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• v.15 no.2
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• pp.174-184
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• 2008

The quality and storage characteristics of low salted onion and five cereals-doenjang (DFO) were investigated. At the DFO, soybean koji ($57{\sim}62%$), onion (3%) and salt (8%) were mixed with equal amount of rice, barley, glutinous millet and glutinous indian millet ($10{\sim}30%$), and water ($7{\sim}12%$). The storage of DFO was done by vacuum packing in polypropylene tube, and sterilized at $121^{\circ}C$. The fermentation and storage was conducted for 60 days at $25^{\circ}C$ at each condition. Control doenjang (GD) was the salinity of 16% soybean doenjang that was not sterilized and packed in plastic containers for storage. During the fermentation, pH of DFO was lower than GD. The pH maintained stability during the storage, and revealed to be lowered, as the proportion of mixed cereals was higher. During the fermentation of DFO, the brix degree revealed to be higher than GD and maintained s1ability during the storage. During the fermentation and storage, the amino nitrogen content of DFO was ranged $400{\sim}470mg%$ by showing higher content than GD and maintained stable content during the storage. During the fermentation, the activities of protease and ${\beta}$-amylase were maintained to be high at DFO, but the activities during the storage were high at GD. The color $L^*$ value of DFO during fermentation and storage maintained higher values than GD, but $a^*$ value revealed lower pattern. Total free amino acids of DFO was ranged $1,918{\sim}2,290mg%$ which was higher than GD that recorded 1,291 mg%. When the sensory evaluation was conducted for DFO that was fermented and stored for 60 days, the DFO mixed with $20{\sim}30%$ of cereals resulted to have more savory taste, flavor, and sweeter than GD, and overall acceptability for color and overall taste was high.

• Journal of the Korean Institute of Navigation
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• v.11 no.1
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• pp.39-65
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• 1987

Since the middle of 1950's, containerization has been rapidly spread over the world in virtue of great merits providing to interensts, and the fundamental changes in port management and prot operations are resulted. As the container terminal is a complex system which is consisted of various subsystems, the treatment for improving the productivity is required in a comprehensive fashion, both in each of its parts and as an integrated system. This paper aims to make an intensive analysis of the Busan Container Terminal system, especially focusing on its subsystems such as ship operation system, storage system and transfer system. First of all, the intrinsic capacity of various subsystems is calculated and it is checked whether the current operation is being performed effectively through the formal analysis. Secondly, the suggestion is presented to improve the operation by considering the throughput that the port of Busan will have to accept in the near future. The results are as follows; 1) As the inefficiency is due to the imbalance between various subsystems at Busan terminal, transfer equipment level must be up to 31% for straddle carrier and 67% transfer crane above all. 2) The yard capacity must be increased by reducing the free dwell time of containers in order to accept the traffic volume smoothly in the near future. 3) The better way to reduce the port congestion is to change berthing rule from the FIFP to the Pre-allocated system by considering the ship arrival pattern.