• Journal of the Korean Society for Precision Engineering
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• v.28 no.5
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• pp.559-564
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• 2011

For the safety of railway, it should be evaluated for the running safety by measuring the derailment coefficient. Although railway has run the fixed and maintained rail, some of railway is derailed. This report shows the results that performed the static load test, main line running test on the basis of the derailment theory and experience. It is executed main line test into more than 90km/h for estimating the curving performance and running safety of depressed center flat car of 3-axle bogie. As the test results, could confirm the curving performance and running safety of depressed center fiat car of 3-axle bogie from the results of the wheel unloading, lateral force, derailment coefficient etc. Derailment coefficient was less than 0.6, and lateral force allowance limit and wheel load reduction ratio were enough safe.

• Land and Housing Review
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• v.11 no.2
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• pp.69-74
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• 2020

The purpose of this study is to investigate the effect of floor area ratio incentive system for Long-life housing certification system by simulation of five recently built apartment complexes. Apartments that are certified as superior in Long-life housing can receive 10% of the floor are incentive in Seoul. However, the difference between base and permitted floor area ratio are in general residential area of class 2 and 3 is not more than 20%. limit of feasible allowance incentive is limited. Even if there is an unrealized permitted floor area ratio, there is no reason to apply the Long-life housing certification system preferentially. Because the items of the floor area ratio incentive provided by the District Unit Plan are various, it shows that the floor space ratio incentive for Long-life housing certification system has little effectiveness. To enhance the feasibility of incentives for the Long-life housing certification system, improvement in the urban planning level, including district unit planning, including the design criteria for apartments in Seoul, is needed.

• Journal of the Korean Institute of Landscape Architecture
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• v.22 no.2
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• pp.39-52
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• 1994

Existing natural resources were analyzed in regional scale in order to suggest natural park guidelines as a previous step of conservation plan. Results of both existing natural resources and land potentiality in preceding paper were combined to suggest comprehensive and qualitative method for understanding of natural land. Regional characteristics of natural park were, then, analyzed by this method, and specific planning guidelines were discussed. The existing natural resources were analyzed by the degree of location quotient, which were found by comparison of the grade of vegetation naturalness and the bio-physical land unit in preceding paper. Then, allowance of existing natural resources was identified, and importance of protection was described based on this result. The bio-physical land unit on Tokyo Province was found to be composed by smaller land units, which had a variety of relationship with grade of vegetation naturalness: from the specific(1st) to many stages(5th). This meant a characteric of each land unit. By this combined approach, the characteristics and spatial distribution of natural land were discussed in the regional scale, and characteristic of nateral park were analyzed in terms of natural location. National park were located in the land unit where both land capability and importance of portection were the 6th. Quasi national park and 1 province natural park were located in the land unit where land capability was the 6th and importance of protection were the 5th. Seven province natural parks were located in the land unites were both criteria under the 5th were mixed. based on the results of this study, the followings were suggested for specific planning guidelines in the case of Takao quasi nation park: (a) conservative land use within the limit of carrying capacity of this area by the conservation of biotic and abiotic natural resources, (b) conservation of both natural and semi-natural vegetation, (c) utilization of this area as a urban forest.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.913-917
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• 2000

Sixteen adult Barbari bucks were divided into 4 homogeneous groups, each group was offered wheat straw (WS) at levels 75, 100, 125 and 150 per cent of ad libitum intake in a factorial randomized complete block design. All goats were uniformly fed a supplement ($13.5g\;DM/kg\;W^{0.75}$) to fulfill their requirement for protein at maintenance level. The experimental feeding of goats at different levels for 21 days was followed by a digestion trial of 6 days and determination of rate of passage of digesta for 144 h duration, respectively. Intake ($g/kg\;W^{0.75}$) of dry matter (DM), organic matter (OM), digestible DM and digestible OM increased with increase in amount of WS offered. The levels of WS refusals for obtaining upper limit of intake was found to be above 30% of DMO. Concentration of ADF and lignin was significantly lower and CP was higher (p>0.05) in food ingested relative to food offered or refused in response to increasing allowance of WS. Dietary means of particulate rate of passage from rumen, transit time and total mean retention time ranged from 0.032 to 0.036/h, 19.10 to 21.72/h and 58.61 to 61.53/h respectively and did not show significant differences (p>0.05) irrespective of dietary level of WS. The results suggest that DMI and quality of ingested WS would improve with higher rates of offer and refusals (${\geq}30%$ of DMO) without any pronounced effect on passage kinetics of digesta, because of the greater opportunity afforded to goats for selective feeding.

• Transactions of Materials Processing
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• v.17 no.2
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• pp.124-129
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• 2008

Net shape forging technologies give many effects into the costs and qualities for the finished products. So, the studies to reduce the additional machining amount are very important in forging industry. Specially, there are two main topics in cold forging industry, such as, tool life and precision forging. In this study, new forging technique was proposed to eliminate the machining process for fixing up the length and improve the lead accuracy of gear. The luck-up hub is manufactured through many processes, such as upsetting, piercing and direct extrusion. The gear is formed in direct extrusion process; however, lead accuracy of the gear is over allowance limit. Therefore, the additional sizing process must be added. In this study, process design for closed-die forging of a lock-up hub used for a component of automobile transmission was made using three-dimensional finite element simulations, and the strain distributions and velocity distributions are investigated through the post processor. The rigid-plastic finite-element method for back pressure forging has been used in order to reduce development time and die cost. Using the FEM simulation, we found the optimum value of back pressure. The prototypes of lock-up hub parts were forged into the net-shape. In the experiment, lead precision of tooth are measured by the CCMM(Contact Coordinate Measuring Machine). The dimensional accuracy of forged part was improved up to the 40% when back press was applied.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.379-384
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• 2019

This study was to investigate the sorbic acid, benzoic acid and sulfur dioxide in commonly consumed beverages, snacks and instant ramens in Korea. A total of 150 food samples including 50 beverages, 50 snacks and 50 instant ramens were examined using the Korea Food Code method. Sorbic and benzoic acid were analyzed by the HPLC method, whereas sulfur dioxide was measured by Monnier-Williams method. Our results indicated that benzoic acid was detected in six beverages samples, and its concentration was in the range of 3.08-11.94 mg/kg. The contents of both sorbic and benzoic acid in 50 beverage samples did not exceed the residue allowance standards set by the Ministry of Food and Drug Safety (MFDS). Sulfur dioxide was detected in 12 beverages samples, but its content was lower than the detection limit specified in the method by the Korea Food Code. On the other hand, sorbic acid was not detected all samples. These results provide a basic data regarding sorbic acid, benzoic acid and sulfur dioxide in commonly consumed beverages, snacks and instant ramens in Korea.

• Journal of Convergence for Information Technology
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• v.9 no.6
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• pp.35-43
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• 2019

This study was conducted in order to identify consumption and experience of adverse effects of high-caffeine energy drink among high school students. This study was a descriptive survey including 245 students in D city. Data were analyzed using descriptive statistics and ${\chi}^2$ test. In the results, 79.5% of the students had previous experience of energy drink consumption. 50.6% of students were experienced adverse effects, mainly palpitation. Among the general characteristics, there was a significant difference according to the experience of high-caffeine energy drink consumption depending on monthly allowance(p=.019) and drinking(p=.033), and a significant difference from adverse effects depending on gender(p=.001) and health condition(p=.006). Also, there was a significant difference according to the experience of adverse effects depending on drinking reason(p=.040) and drinking time(p=.005). After, policy measures are needed to limit the sale of high-caffeine energy drinks and continuous health education is needed to foster the ability of students to control themselves.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.229-235
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• 2021

To dispose of waste, there are methods such as landfill, incineration, recycling, and sea discharge. Since the landfill wastes accumulate, there is a limit to the landfill site to accommodate them. In this paper, a time series analysis and current status of landfill allowance was analyzed over 20 years of landfills distributed throughout the country using GIS to understand the status of waste reclamation. As a result, the emissions of waste were gradually increasing, and as the emissions increased, the amount of landfill increased. The landfills in the Seoul metropolitan area have been saturated and need to be resolved as soon as possible.

• Journal of Food Hygiene and Safety
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• v.35 no.4
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• pp.398-410
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• 2020

In this study, the contents of soluble vitamins B₁ (thiamin), B₂ (riboflavin), and B₃ (niacin) in 13 kinds of rice, 11 kinds of noodles, and 15 kinds of sauces were identified. The limit of detection (LOD) and limit of quantification (LOQ) were checked to determine the reliability of the experimental results, and the accuracy of the results through the standard reference material (SRM 1849a) was verified to show excellent indicators. As for thiamin, japchaebab (stir-fried glass noodles with rice) was found to contain the highest content among rice dishes, makguksu (buckwheat noodles) among noodle dishes, and tomato spaghetti sauce among sauces. Riboflavin was identified as having the highest content in slightly spicy jajangbab (black-bean sauce with rice), bibimguksu (spicy noodles) for noodles, and spicy curry with turmeric for sauces. Niacin was highest in content in the deep and rich flavors of spicy chicken-fried rice, janchiguksu (banquet noodles), and black-bean sauce, respectively. As a result of checking the amount of recommended daily intake of water-soluble vitamins for Korean adult men and women, the highest content of riboflavin was 217.40% for men and 271.75% for women. Through this study, we are going to establish a database of nutrients for the water-soluble vitamins contained in rice, noodles, and sauces to provide the necessary dietary data concerning the content of the water-soluble vitamins contained in foods for daily recommended intake.

• Fire Science and Engineering
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• v.33 no.6
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• pp.105-113
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• 2019

This study investigates the toxicity characteristics of two Non-Class 1E Cables (For security reasons, we refer to company A and company B) used in nuclear power plants according to the accelerated deterioration period. In accordance with NES 713 test equipment and standards, tests were carried out on non-aged cables and the cables subjected to 20- and 40-year-accelerated-deterioration; each of the cables was further classified into sheath and insulation. The test results showed that the toxicity indices of 20- and 40-year-accelerated-aged cables were higher than those for the non-aged cables, and 20-year-aged cables of both A and B companies showed the highest toxicity indices. This is attributed to the extensive emissions of carbon monoxide and halide gases such as hydrogen chloride and hydrogen bromide. Furthermore, to analyze the toxicity indices of sheath and insulation in detail, the US Department of Defense standard (MIL-DTL) was applied to determine whether the Toxicity index (T.I.) allowance was exceeded, and the results showed that the insulating materials emitted considerably more than the allowable limit.