• Journal of Radiation Protection and Research
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• v.36 no.2
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• pp.59-63
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• 2011

It is important to reduce indirect scattered neutron beside direct neutron of chosen energy for designing a neutron-reference-field laboratory with neutron produced from a nuclear reaction by a accelerator. Therefore MCNPX simulation was performed with various conditions for obtaining such condition. At first in the original laboratory condition we calculated the direct neutron flux which was inserted in chamber (virtual chamber composed of air) of 0 degree (proton moving direction) for neutron flux measurement and the scattered neutron flux which is inserted in the chamber after scattering wall or bottom. In the result, the scattered neutron which was inserted after scattering bottom is more than that which was inserted after scattering the others. Therefore MCNPX simulation was again performed with removing the concrete bottom and with removing the concrete bottom and digging 1 m in the ground. In the result of removing concrete bottom and digging 1 m in the ground, scattered neutron which was inserted after scattering bottom became less than that which was inserted after scattering the others.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.261-268
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• 2018

The use of electric cable was limited due to the installation time and large space as the increase of power demand and load quantity in side line. In order to solve these problems, the application of busway system which can supply the large current was increasing. But it was lack of methods of performance tests to evaluate the reliability and results of test for busway system. In this paper, we presented items to evaluate the reliability test for epoxy coated busway system with reference to IEC 61349-6. In addition, we proposed items to evaluate the reliability and long term life cycle test for the epoxy coated busway system. The combined acceleration deterioration test that reflects actual conditions of the survey as much as possible was conducted considering both thermal and electrical stresses. The deterioration condition was selected to satisfy fifty years life expectation and the insulation performance verification test of the busway system confirmed the long term life prediction. Furthermore, as test items for reliability assessment of compliance with the environment for the use of temperature, humidity and load current where busway system was installed, thermal overload test, water immersion test, cold shock temperature test and thermal cycle test were performed. And we examined changes in characteristics and abnormality after tests. From results, the test items presented to evaluate performance and reliability of the epoxy insulated busway system were confirmed to be appropriate in this paper, and the performance of the product was also confirmed to be excellent for reliability tests.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.246-252
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• 2020

Safety accidents have been reported due to falling accumulated snow from cables of cable-supported bridges. In addition to the direct damage caused by falling snow, secondary damage, such as traffic accidents, can occur. Various methods have been proposed to prevent these accidents, but there are still problems in safety and practicality. In this study, a cable robot type was selected as one of the active methods for removing accumulated snow on cables. An attempt was made to increase the climbing ability of the robot to improve the efficiency of snow removal. In addition, the available range of cable diameter for the robot can be adjusted flexibly to be applied to cables used in the field. A high-resolution camera was also installed to check the surface condition of the cable in real time to increase the utility, and be used as a cable inspection robot. A three-axis accelerometer and a tension conversion algorithm were added to measure the tension force of cables. To verify the performance, indoor and field experiments were conducted, and future improvements for the inspection robot were proposed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.63-72
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• 2012

The high-flowing concrete requires additionally or excessively more expensive admixture than conventional concrete. So, the concrete has not to be widely used in practical field due to the increase of production price, need of additional facilities, and excessive development of concrete strength in associate with addition of too much cementitious material even though it has more significant advantages than conventional concrete. Thus, this study aims at developing high-flowing concrete with general strength unlike high strength which has been carried out in conventional study. To observe the role of aggregate in the concrete quantitatively and to increase the performance of high-flowing concrete effectively, parametric studies were carried out such as W/C, s/a, fineness modulus of aggregate, contribution degree of particle sizes, and the effect of 13mm aggregate and fine stone powder as a partial replacement of aggregates. And the effect of these factors on performance of the concrete was evaluated by measuring slump-flow and gap of penetration height in U-typed instrument. As a result, it was found that flowability of high-flowing concrete depends upon grading of fine aggregate more significantly than that of coarse aggregate and is enhanced greatly as fineness modulus of fine aggregate decreases and the value of s/a increases. In addition, the application of 13mm aggregate and fine stone powder are expected as a partial replacement of aggregate in order to increase the performance of high-flowing concrete more effectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.663-668
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• 2000

To develop natural intermediate flavoring substances, optimal processing conditions and qualities for two stage enzyme hydrolysate (TSEH) from low-utilized small longfinned squid were investigated. The optimal conditions for TSEH method were found as digestion with Alcalase (0.2% w/w-sample, pH 8.0) at 55$^{\circ}C$ 3 hours at the 1st stage and with Neutrase (exo-peptidase, 0.2% w/w-sample, pH 6.0) at 45$^{\circ}C$ for 2~3 hours at the 2nd stage. Among the method of water extract, autolytic extract and various kinds yields, transparency and organoleptic taste. From the results of chemical experiments and sensory evaluation, longfinned squid TSEH is flavorable as the natural intermediate taste-active substances for fisheries products such as soup base, squid-taste pasty and snacks.

• Journal of the Korean Electrochemical Society
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• v.4 no.3
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• pp.132-137
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• 2001

Recently, the demand for notebook PC with lithium ion batteries has steadily increased and consumers require them to adopt a SBP(smart battery pack) able to predict the remaining capacity and the run time of batteries precisely. The SBP is composed of a protection If, by which safety of lithium ion batteries is maintained against overcharge, overdischarge and overcurrent, and a smart IC, which calculates the remaining capacity and the remaining run time. The protection IC shut abmormal current down by using overcharge/overdischarge FET. A SBS(smart battery system) is composed of a system host, a smart battery and a smart battery charger. The smart ICs for SBP will be required to provide a low cost, low current consumption and small size. There will need to develop a microcomputer control type IC and an optimum algorism which is able to predict the residual capacity and the residual run time precisely. SBS will apply to many kinds of industry fields such as an electric bicycle, an electric vehicle, a load levelling and a military.

• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.127-145
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• 1998

Unlike water or air quality standards that have been established by legislation using potential human health impact as the primary criterion, soil quality depends on the soils primary function and its relevant environmental factors, which is much more site- and soil specific. A properly characterized soil quality assessment system should serve as an indicator of the soil capacity to produce safe and nutritious food, to enhance human and animal health, and to overcome degrative processes. For our proposed example, a high quality soil with regard to maintaining an adequate soil productivity as a food production resources must accommodate soil and water properties, food chain, sustainability and utilization, environment, and profitability, that (i) facilitate water transfer and absorption, (ii) sustain plant growth, (iii) resist physical degradation of soil, (iv) produce a safe food resources, (v) cost-effective agricultural management. Possible soil quality indicators are identified at several levels within the framework for each of these functions. Each indicator is assigned a priority or weight that reflects its relative importance using a multi-objective approach based on principles of systems to be considered. To do this, individual scoring system is differentiated by the several levels from low to very high category or point scoring ranging from 0 to 10, And then weights are multiplied and products are summed to provide an overall soil quality rating based on several physical and chemical indicators. Tlne framework and procedure in developing the soil quality assessment are determined by using information collected from an alternative and conventional farm practices in the regions. The use of an expanded framework for assessing effects of other processes, management practices, or policy issues on soil quality is also considered. To develop one possible form for a soil quality index, we should permit coupling the soil characteristics with assessment system based on soil properties and incoming and resident chemicals. The purpose of this paper is to discuss approaches to defining and assessing soil quality and to suggest the factors to be considered.

• Journal of radiological science and technology
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• v.35 no.4
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• pp.321-326
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• 2012

Used as an ingredient in the hospital for orthopedic prosthetic stainless and titanium metal the same size as on the MRI diagnostic value of imaging were compared. Center of images, background high band portion of the video signal is converted into a weighted intensity values Normal images and compared. The area of normal slice and also the distortion of images and cross-sectional imaging of a range of quantitative and sagittal planes were compared. As a result, the periphery high band signal intensity values of Stainless video phantom 2, pig bone 1.8, Titanium imaging of phantom 1.7 has higher value than Normal video pig bone 1.3 times the signal strength rivers. MRI distortion of the shape and the distortions of the range, if the cross-sectional area compared to Normal Slice Stainless case of phantom 65.8 %, pig bone 61.5 %, Titanium distortion phantom 23.1 %, pig bone 38.5 % of the range of community found. In this experiment, as a result, MRI was found to be Titanium more diagnostic value than the specimen with respect to the signal intensity weighted value and low distortion range, Stainless.

• Applied Biological Chemistry
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• v.44 no.4
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• pp.262-268
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• 2001

Two commercial wood vinegar liquors prepared from Cryptomeria japonica and Quercus sp., which are used as a mineral fertilizer in Korea, were extracted using dichloromethane as a solvent, respectively. The extracts were separated into acidic, phenolic, neutral and basic fraction by acid or alkali treatment, and the compositions of each fraction were analyzed by means of GC and GC-MS. A total of 103 compounds including 26 acids, 32 phenols and 45 neutral compounds were identified. The major components were acetic, propionic and n-butyric acid, representing of $41{\sim}58%$ of the acidic fraction, guaiacol, 4-methylguaiacol and phenol, repersenting of $53.2{\sim}63.9%$ of the phenolic fraction, and furfural, 3-methyl-2-cyclopenten-2-one, 2,3-dimethyl-2-cyclopenten-1-one and 5-methyl-2-furfural in the neutral fraction. In addition to these compounds, phenolic fraction in dichloromathane extract from wood vinegar liquor of C. japonica included large amounts of vanillin, acetovanillone and tentatively identified ethylvanillyl ether while that of Quercus sp. included some amounts of syringol and 4-methylsyringol.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.207-213
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• 2003

Kochujang was prepared for this study with raw material inoculated by commercial enzyme of amylase and protease. Volati1e compounds of Kochujang were analyzed using a purge and trap method during fermentation and identified with GC-MSD. Total 54 kinds of volatile flavor components like 16 kinds of alcohol, 16 kinds of ester, 7 kinds of acid, 4 kinds of aldehyde, 2 kinds of alkane, 1 kind of benzene, 3 kinds of ketone, 1 kind of alkene, 2 kind of amine, 1 kind of phenol, other 1 were found. Total number of volatile flavor detected right after manufacturing were 23 kinds like 3 kinds of alcohol, 6 kinds of ester, 3 kinds of aldehyde. After 30 days storage, total number of volatile flavor went up to 31 kinds with addition of 4 kinds of alcohol, 1 kind of ester. The total number of volatile flavor after 120 days storage were increased to 49 kinds. Volatile flavor compounds detected during the storage period were total 20 kinds like 6 kinds of alcohol such as 2-methyl-1-propanol, ethanol, 3-methyl-1-butanol, 5 kinds of ester such as ethyl acetate, isoamyl acetate, ethyl butyrate, 3 kinds of aldehyde such as butanal, acetaldehyde and 6 kinds of others. Even though peak area % of flavor compound varied depends on fermentation period, ethanol, ethyl acetate, ethyl butyrate, ethenone, 2-methyl-1-propanol, 3-methyl-1-butanol were the main compounds that consisted of flavor from Kochujang which was made with enzyme treatment. Ethly acetate showed the highest result in the treatment of right after manufacturing, 3-methyl-1-butanol had up to 90th day and ether were the other days.