• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.535-543
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• 2017

For column-beam gussets of wooden structures, slit-processed members inserted with a steel plate are used in general. In this study, a rigid portal frame bonded with a joint was fabricated and a semi-rigid portal frame was fabricated by making a wooden gusset, a replacement for steel plate, of which a half was integrated into the column member and the other half was joined with the beam member by drift-pins. The lateral strength performance of the wooden portal frame was compared with that of the steel plate-inserted joint portal frame. The lateral strength performance was evaluated through a perfect elasto-plasticity model analysis, sectional stiffness change rate, and short-term permissible shear strength. As a result of the experiment, the maximum strength of the rigid portal frame was lower than that of the steel plate-inserted joint portal frame. The yield strength and ultimate strength were calculated as 0.58 and 0.48, respectively, but the measurements of initial stiffness and cumulative ductility improved by 1.35 and 1.1, respectively. As a result of the perfect elasto-plasticity model analysis of the semi-rigid portal frame, the maximum strength was lower than that of the rigid portal frame, but the toughness after failure was excellent. Thus, the ultimate strength was higher by 1.05~1.07. The steel plate-inserted portal frame showed rapid decrease in stiffness with the progress of repeated tests, but the stiffness of the portal frames with a wooden joint decreased slowly.

• Journal of Korean Society for Atmospheric Environment
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• v.3 no.1
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• pp.27-33
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• 1987

The environment and biological studies of tritium have been carried out in the advanced countries since the mid 1950's. In the case of a potential tritium exposure, the usual procedure is trifium bioassay (as HTO) in human urine in order to determine the amount of tritium deposited in the body called tritium body burden. The maximum permissible body burden(MPBB) of tritium in total body is about $30{\mu}Ci/{\ell}$ for body tissue. In the bioassay, the most common investigation level for detection of tritium in urine is 1/10th of MPBB. For this bioassay project, the first priority is given to obtaining a quench correction curve. This consideration is necessary because of the variability in color of human urine specimens. Quenching effect in this case mainly is caused by the absorption of scintillation light flashes by the urine sample. By the least squares method on the statistical basis, an estimated formula for quench correction curve was determined to be Y = 0.771 + 1.836 ${\tmes}10^{-4}$X, where the efficiency(Y) was ranged from about 12% to 31% in the liquid scientillation counting. In this paper, a brief theory concerning the biological half-life of tritium and the retention formula to apply to systematically distributed tritium are described.

• Journal of Environmental Impact Assessment
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• v.16 no.2
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• pp.143-156
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• 2007

This study has researched the management status and the pollution level of water, soil, stream sediments of 11 abandoned coal mines out of a total of 12 within Obong-Dam area except Bukyung mine, which was submerged when constructing Obong-Dam, and selected areas which are in needs to have pollution control facilities in the first place. From the results of examination on the runoff at the waste rock pile and mineheads, the runoff from Sueun mine (pH, Fe, Al), Samwon mine (pH, Al), Wangdo mine (pH, Al), Mose mine (pH, Fe, Al) and Daeryeong mine (pH) exceeded the permissible discharge standards of the water quality, but the water at merging point with Obong-Dam after joined with Doma branch satisfied both Water Quality Standards and Drinking Water Quality Standards. In regard to groundwater contamination, it is found that areas where exceeded the Drinking Water Quality Standards are Wangdo mine (pH), Jangjae mine (pH, Zn), Daeryeong mine (pH) whereas all areas satisfied Soil Contamination Warning Standards of Soil Environmental Conservation Law. When comparing a research result on underwater sediments of branches of abandoned mines to the EPA Guidelines for classification of great lakes harbor sediments, Dongguk Gaerim (Fe), Jungwon mine (Fe), Daebo mine (Mn), Samwon mine (Mn) and Daeryeong mine (Mn) showed mid-level of contamination, whereas Sueun (Fe, Mn), Daebo mine (Fe), Woosung mine (Fe, Mn), Wangdo mine (Fe, Mn), Mose mine (Fe) and Daeryeong mine (Fe) showed high-level of contamination. In addition, contamination levels of underwater sediments in Wangsan and Doma branch where abandoned mine's branches merge together, Wangsan branch showed no contamination at all whereas Doma branch shows mid-level of contamination which reflect the Doma branch is affected by waste rock pile and minehead runoff of the abandoned mines in the Doma branch area. It is concluded that Mose mine and Sueun mine required treatment of acid mine drainage. and Wangdo, Jungwon, and Samwon mines were in need of mine tailing and erosion control work. The Samwon mine additionally required a control system for closed minehead runoff. Although the Samwon mine reached a high concentration of Al, Mn $Ca^{2+}$, $SO{_4}^{2-}$ in the runoff, the levels decreased after it was combined with a tributary. It has been concluded that after further monitoring of the cause of pollution, a preventive measure system may be needed to be built.

• The Journal of Korean Society for Radiation Therapy
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• v.11 no.1
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• pp.43-48
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• 1999

Purpose : For practical application of the MR image for stereotactic radiosurgery, the target point achieved by acquisition of MR image in a relatively homogeneous phantom has to agree with the actual isocenter of irradiation in real radiosurgery and the amount of distortion of the MR image should be known. Materials and Methods : A dosimetric film with a random target point was inserted into a radish vertically and horizontally on axis Z and they were fixed with a headring. After image acquisition by stereotactic radiosurgery planning system, we achieved stereotactic coordinate of the target point and examined irradiation using the coordinate acquired as isocenter. After the irradiation, the film in the radish was developed and processed and the degree of coincidence between the target point marked on the film and the center of the radiation distribution. In order to measure the degree of distortion of the MR image in a different way, an acryl phantom was made and punctures were made at intervals of 1 cm and a drop of oil was dropped into it. Then, it was inserted into the radish vertically and horizontally on axis Z to acquire the MR image. Each coordinate was achieved and the estimation of distortion of MR image was made both in vertical and horizontal directions Results : The film from the radio was developed and for the one inserted vertically on axis Z, there was a good coincidence in the discrepancy between the target point marked on the film and the center of the radiation distribution. For the one inserted horizontally, the discrepancy between them was under 0.5 mm. As a result of estimating distortion of MR image using acryl, the discrepancy was under 0.45 mm in the case of the phantom inserted vertically on axis Z, and that of the one inserted horizontally was 1.4 mm. Conclusion : We were able to confirm good coincidence in homogeneous phantom in actual treatment position of radiosurgery using the MR image and the discrepancy measured in the analysis of distortion of the MR image did not exceed the permissible level. Therefore, it was evident the system of the hospital is suitable for radiosurgery using MR image.

• Journal of Embryo Transfer
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• v.21 no.4
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• pp.339-344
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• 2006

This study was to investigate the optimal short-term storage diluents for goat spermatozoa. Semen was collected with electro-ejaculation from two goats. The collected semen was diluted in BTS and centrifuged at 500 g for 5 minutes. The supernatant was discarded and diluted with BTS, Modena or Triladyl$^{(R)}$ and stored at 4 or $17^{\circ}C$ for 8 days. The motility of spermatozoa in BTS and Modena stored at $4^{\circ}C$ was rapidly decreased at day 1. The motility of spermatozoa in BTS at $17^{\circ}C$ was decreased to 30$\sim$45% at day 2. In Modena at $17^{\circ}C$, the inappropriate motility fur artificial insemination (AI) was reached at day 4. The spermatozoa stored in Triladyl$^{(R)}$ at 4 or $17^{\circ}C$ were more viable and higher motility up to day 4. In conclusion, liquid storage of goat spermatozoa in Triladyl$^{(R)}$ at 4 or $17^{\circ}C$ for 4 days showed permissible viability for AI.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.1
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• pp.1-5
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• 2011

Purpose: Measurement of the horizontal and vertical prism diopter was investigated which was occurred due to distance differences between the optical inter-centeral distance (OC) and the interpupillary distance (PD) of the prescribed glasses. Methods: We surveyed 96 subjects (192 eyes) at the average age of 21.56 years old. The PD was measured by using the PD measurement system (DONGYANG PD-85, Korea), and the OC of the glasses was measured by using the projective peak refractive power measurement system (TOPCON CL-200, Japan). The OH value was measured by using Penlight and the PD ruler. Results: The PD which had been measured by the PD system and the OC of the glasses revealed 78.1% of differences. 62.5% of the objects were base-in value prescribed glasses; 58.3% were out of permissible error. Only 8 subject showed concurrence between the prescribed glasses and the OH value, and 82.3% of the objects were induced vertical prism of over 1 (prism diopter). Conclusions: In order to improve the vision function of people who wear glasses, it is necessary to advance the accuracy of PD, OH measurement and making glasses as well.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.3
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• pp.409-420
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• 2017

The amount of ventilation required in making the tunnel ventilation plan is an important factor for determining the capacity of the ventilation system. The amount of pollutant emission for each type of vehicle (basic emission amount for the design of ventilation volume) for estimating the required ventilation amount is based on the 'Standard for Allowing the Emission for the car manufacturing', proposed by Ministry of Environment. However, in 2013, the Ministry of Environment announced the 'Regulations on the calculation method of total emissions from vehicles' as a regulation for calculating the pollutants emitted from vehicles. In this regulation, there are the 'Emission factors for each type of vehicle'. Therefore, it is necessary to review the application of the Regulation to the estimation of the required ventilation volume for the road tunnel. In this study, the influence of the strengthened emission regulation in 2015 caused by the case of manipulation of emission volume for the diesel vehicle on the calculation of the required ventilation volume in the road tunnel has been checked. In addition, in this study, the required ventilation volume calculated according to the Standard for Allowing the Emission for the car manufacturing revised by Ministry of Environment and "Emission factors for each type of vehicle" and that calculated according to the EURO emission standard were compared for analysis. This study has implications that it provides the basic design data for calculating the reasonable ventilation capacity of the ventilation system based on the ground for calculating the required ventilation volume.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.3
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• pp.295-303
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• 2014

Purpose: This study aims to observe bleaching resulted from multipurpose contact lens solutions used to manage lenses with the subjects of colored contact lenses being distributed in Korea. Methods: The lenses have been worn for six months, and their refraction is 0.00D. Three types of colored contact lenses of which margin has been colored with a different manufacturing method have been adopted (type 1: pigment application method, type 2: chemical bonding process, type 3: sandwich method), and multipurpose solutions used were two types containing different components. Each of the colored contact lenses was stored in the multipurpose solutions for 20 days and went through vortexing for 15 seconds per day. Their fluorescence absorbance, surface roughness, brightness index, and color coordinate index were measured before and after the vortexing to see the degree of bleaching. Results: In the two types of multipurpose solutions, every type of the color contact lenses showed no statistically significant difference in their fluorescence absorbance value before and after the vortexing. Regarding surface image, the front surface of the lenses was smooth in every type, and about the back surface, type 3 indicated less protrusion than type 1 and 2. About the difference of color on the lens surface before and after the vortexing, type 3 showed significantly less difference than type 1 and 2; however, all fell into the permissible error. Conclusions: About the bleaching of colored contact lenses resulted from multipurpose solutions for soft contact lenses, there was no difference observed in terms of fluorescence absorbance and color. According to the methods of manufacturing dyes, however, there was difference in the protrusion of the posterior surface image.

• Korean Journal of Veterinary Service
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• v.39 no.1
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• pp.13-20
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• 2016

This study is aimed to find out distribution status of online-market livestock products by purchasing and examining 120 cases of livestock products (seasoned meat: 17, 33 cases of packaged meat, 23 cases of ground meat, 19 cases of ham, 11 cases of sausage, 4 cases of bacon, 1 case of meat processing, 8 cases of Meat extract processed, and 4 cased of Dry storage of meat) at 17 On-line markets from April to August. 2015. We checked the weight of them first, and carried out ingredients test for each of processed meats. And we performed gene screening test on the products which were labelled 'Hanwoo' to investigate that the products were made of Korean native cattle. we also carried out test of identifying domestic animal species on ham, sausage and ground processed products. After weighing all products, we could know that all of them were delivered more than labelled weight or in allowable error. The result values of test which measured level of preservatives, Nitrite, Volatile Basic Nitrite (VBN), and tar Color by the type of processed meat products were in permissible range or not detected. Also, 17 beefs inspected Korean native cattle gene test were confirmed that they were made by real korean native cattle. But 2 cases of Ham, sausage, and ground processed products had difference between label and goods. In this study, we could make a decision that livestock products, distributed in On-line markets, were safe and expect to make higher degrees of hygiene for livestock products seller. Futhermore, we hoped result of this study could be used by basic data for progressive national policy decisions.

• Korean Journal of Agricultural Science
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• v.8 no.1
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• pp.126-132
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• 1981

Rice grains harvested from paddy fields around industrial areas of Kyongin, Iri, and Jeonju were taken and analysed the contents of heavy metals which were considered to be accumulated in those rice grains. Atomic absorption spectrophotometer was applied for analysis of heavy metals such as copper(Cu), zinc(Zn), lead(Pb) and cadmium (Cd) in unpolished rice grains. The content of Cu in rice grains harvested from Iri was the lowest, 2.94 ppm, while those from Seo-Myon, Shiheung-Gun was the highest, 3.65 ppm. The contents of Zn and Pb in rice grains were ranged 20.56~27.21 ppm and 0.38~0.53 ppm, respectively. Cd content were exceptionally lower than the regulated level, 1.0 ppm. The content of this metal detected in rice grains from Seo-Myon was the highest, 0.509 ppm, but those of other areas were much lower, ranged 0.040~0.136 ppm. The present concentrations of Cu, Zn, and Pb in rice grains were also lower than the expected level and below the maximum permissible concentrations.