• Title/Summary/Keyword: 허용위험도

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A study on measures for the mitigation of fire damage in Korea super high-rise building through the improvement of domestic·foreign standards (국·내외 기준개선을 통한 국내 초고층 건축물의 화재피해경감 대책에 관한 연구)

  • Ko, Jaesun
    • Journal of the Society of Disaster Information
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    • v.13 no.2
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    • pp.233-248
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    • 2017
  • Uniform laws and regulations and reasonable design is necessary for the prevention of possible fire in super high-rise building. To this end, this study focused on super high-rise and massive building-related architectural review performance-based design (PBD) evaluation disaster impact assessment (DIA), and provided fire engineering measures for improving fire prevention on the basis of performance-based design by analyzing the buildings subject to these systems and problems in terms of contents. Above all, in the aspect of law and standard improvement, first, with regard to dual parts of two statutes though significant portion of them has the same contents in performance-based design (PBD) evaluation and disaster impact assessment (DIA), it is necessary to operate the systems after making them conform with each other and consolidating or abolishing them. Second, if it is impossible to consolidate or abolish performance-based design (PBD) evaluation and disaster impact assessment (DIA), the areas of contents of performance-based design (PBD) evaluation and disaster impact assessment (DIA) should be precisely classified and established. Next, engineering improvement measures against fire hazard in super high-rise building are as follows. First, it is necessary to revise the provisions of straight-run stairs in special escape stairs. And in case of installing a mechanical smoke exhaust system instead of smoke vent, sandwich pressurization used in the United Stated should be permitted. Second, with regard to smoke control system for special escape stairs, it was shown that there was necessity for revising the standards in order to enable air to be supplied according to section in case of fire, carrying out performance-based design, and the like from the early design stages to the completion stages. In the future, it is expected that an epoch-making contribution will be made to a decrease in casualties and property damage due to fire in case of super high-rise building where the results can be reflected after carrying out a study on maintenance and carrying out an additional study on other considerations of super high-rise building together with reflecting the improvement measures provided in the above-mentioned study.

Survey on the High-Caffeine Energy Drink Consumption Status of University Students in Seoul (서울 지역 대학생의 고카페인 에너지음료 소비 실태 조사)

  • Yoo, Hyun Suk;Sim, Ki Hyeon
    • Journal of the East Asian Society of Dietary Life
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    • v.24 no.3
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    • pp.407-420
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    • 2014
  • A survey was carried out regarding university students' recognition of high-caffeine energy drinks in an effort to identify and improve problems as well as provide basic data. Most of the subjects had previous experience of energy drink consumption. Studies showed that most students consumed energy drinks when studying. Regarding frequency of energy drink consumption, most students' responded "1~6 times a year"; female students showed lower frequency of energy drink consumption than male students. Both male and female students used convenience stores to purchase energy drinks. In most cases, students became aware of energy drinks through advertisements on TV, radio, newspapers, and magazines. The most important factor affecting their energy drink purchase and consumption status was taste. The most frequent adverse effect they experienced after drinking an energy drink was unusual heart-pounding, whereas the biggest problem caused by energy drink consumption was addiction. This study indicates that students should have a better understanding of the problems associated with excessive and prolonged high-caffeine intake. In addition, instructions for proper purchasing and consumption of high-caffeine energy drinks should be provided as well as education and campaigns concerning symptoms caused by high-caffeine energy drink consumption so that students may refrain from excessive consumption. Further, civil organizations and the government need to devise effective measures for proper regulation of high-caffeine energy drink consumption.

Occurrence of Mycotoxins in Korean Grains and Their Simultaneous Analysis (한국산 곡류에서의 곰팡이독소 오염현황 및 동시분석)

  • Kim, Dong-Ho;Jang, Han-Sub;Choi, Gyu-Il;Kim, Hyun-Jung;Kim, Ho-Jin;Kim, Hyo-Lin;Cho, Hyun-Jung;Lee, Chan
    • Korean Journal of Food Science and Technology
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    • v.45 no.1
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    • pp.111-119
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    • 2013
  • Eleven mycotoxins, including aflatoxins, ochratoxin A, fumonisins, zearalenone, T-2 toxin, deoxynivalenol, and HT-2 toxin, were analyzed simultaneously in rice, barley, and maize produced in 2011 by liquid chromatography coupled with triple quadrupole mass spectrometry (LC/MS/MS). Limits of detection (LOD) are 0.2 ${\mu}g/kg$ for aflatoxin $B_1$, and $G_1$, 0.3 ${\mu}g/kg$ for aflatoxins $B_2$, and $G_2$, 0.1 ${\mu}g/kg$ for ochratoxin, fumonisins, zearalenone, and T-2 toxin and 3.0 ${\mu}g/kg$ for deoxynivalenol and HT-2 toxin. Limits of quantification (LOQ) were 0.6 ${\mu}g/kg$ for aflatoxins $B_1$, and $G_1$, 0.9 ${\mu}g/kg$ for aflatoxins $B_2$, and $G_2$, 0.3 ${\mu}g/kg$ for ochratoxin, fumonisins, zearalenone, and T-2 toxin and 10.0 ${\mu}g/kg$ for deoxynivalenol and HT-2 toxin. Recoveries for 11 mycotoxins ranged from 70.45 to 111.11%. Fumonisins, deoxynivalenol, and zaeralenone were detected from 0.9 to 334.0 ${\mu}g/kg$ in the polished rice, barley and raw corn cultivated in Korea. Other mycotoxins were not detected. Deoxynivalenol contamination was mainly found in barley (24 out of 43 samples) and the average value in positive samples was 113.30 ${\mu}g/kg$.

Evaluation of the Usefulness for VMAT of multiple brain metastasis using jaw tracking (Jaw tracking을 이용한 다발성 뇌 전이의 용적세기조절회전치료에 대한 유용성 평가)

  • Kim, Tae Won;Yoo, Soon Mi;Jeon, Soo Dong;Yoon, In Ha;Back, Geum Mun
    • The Journal of Korean Society for Radiation Therapy
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    • v.30 no.1_2
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    • pp.73-81
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    • 2018
  • Purpose : The aims of this study were to compare and assess the effectiveness of Volumetric Modulated Arc Therapy(VMAT) using jaw tracking(JT) and fixed jaw(FJ) in radiation therapy of multiple brain metastasis. Methode and material : Among the patients with Multiple Brain Metastasis treated with jaw tracking, 10 patients with more than 6 tumors and with the size of radiation field $14{\times}14cm^2$ or more were included. Each Treatment plans with jaw tracking(JT) and fixed jaw(FJ) was established with Eclipse (Ver. 13.6 Varian, USA). Gamma Index (3 mm, 3 % confidence interval - 95 %) and maximum dose difference were measured with an electronic portal imaging device(EPID). The $D_{max}$ and $D_{mean}$ of Organ At Risk(OAR) were assessed and compared, and the Conformity Index(CI) and Homogeneity Index(HI) were evaluated. Result : Evaluating jaw tracking(JT) and fixed jaw(FJ) outcomes, in all cases, Gamma Index met the permissible standard of 3 mm, 3 % confidence intervals of 95 %. The maximum dose difference value from the areas with leaf end transmission was measured at a maximum of 98.4 % and an average of 43.6 % in clockwise(CW), and 67.9 % and 41.0 % for each in Counter-Clockwise(CCW). With jaw tracking, the maximum value of $D_{max}$ for each normal organ in OAR decreased in 15.36 %~74.59 % with the average value decreasing in 2.84 %~39.80 %. The maximum value of $D_{mean}$ in OAR decreased in 27.90 %~65.23 %, with the average value decreasing in 7.70 %~41.71 %. No change has been found in Conformity Index and Homogeneity Index values. Conclusion : When Jaw tracking is used in treating patients with multiple brain metastasis with VMAT, the unnecessary exposure due to leakage and transmission of radiation in unspecified areas was reduced, without affecting the dose distribution of the planning target volume(PTV), and the availability of radiation therapy with lower doses in normal organs is expected.

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Studies on the Kiln Drying Characteristics of Several Commercial Woods of Korea (국산 유용 수종재의 인공건조 특성에 관한 연구)

  • Chung, Byung-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.2 no.2
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    • pp.8-12
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    • 1974
  • 1. If one unity is given to the prongs whose ends touch each other for estimating the internal stresses occuring in it, the internal stresses which are developed in the open prongs can be evaluated by the ratio to the unity. In accordance with the above statement, an equation was derived as follows. For employing this equation, the prongs should be made as shown in Fig. I, and be measured A and B' as indicated in Fig. l. A more precise value will result as the angle (J becomes smaller. $CH=\frac{(A-B') (4W+A) (4W-A)}{2A[(2W+(A-B')][2W-(A-B')]}{\times}100%$ where A is thickness of the prong, B' is the distance between the two prongs shown in Fig. 1 and CH is the value of internal stress expressed by percentage. It precision is not required, the equation can be simplified as follows. $CH=\frac{A-B'}{A}{\times}200%$ 2. Under scheduled drying condition III the kiln, when the weight of a sample board is constant, the moisture content of the shell of a sample board in the case of a normal casehardening is lower than that of the equilibrium moisture content which is indicated by the Forest Products Laboratory, U. S. Department of Agriculture. This result is usually true, especially in a thin sample board. A thick unseasoned or reverse casehardened sample does not follow in the above statement. 3. The results in the comparison of drying rate with five different kinds of wood given in Table 1 show that the these drying rates, i.e., the quantity of water evaporated from the surface area of I centimeter square per hour, are graded by the order of their magnitude as follows. (1) Ginkgo biloba Linne (2) Diospyros Kaki Thumberg. (3) Pinus densiflora Sieb. et Zucc. (4) Larix kaempheri Sargent (5) Castanea crenata Sieb. et Zucc. It is shown, for example, that at the moisture content of 20 percent the highest value revealed by the Ginkgo biloba is in the order of 3.8 times as great as that for Castanea crenata Sieb. & Zucc. which has the lowest value. Especially below the moisture content of 26 percent, the drying rate, i.e., the function of moisture content in percentage, is represented by the linear equation. All of these linear equations are highly significant in testing the confficient of X i. e., moisture content in percentage. In the Table 2, the symbols are expressed as follows; Y is the quantity of water evaporated from the surface area of 1 centimeter square per hour, and X is the moisture content of the percentage. The drying rate is plotted against the moisture content of the percentage as in Fig. 2. 4. One hundred times the ratio(P%) of the number of samples occuring in the CH 4 class (from 76 to 100% of CH ratio) within the total number of saplmes tested to those of the total which underlie the given SR ratio is measured in Table 3. (The 9% indicated above is assumed as the danger probability in percentage). In summarizing above results, the conclusion is in Table 4. NOTE: In Table 4, the column numbers such as 1. 2 and 3 imply as follows, respectively. 1) The minimum SR ratio which does not reveal the CH 4, class is indicated as in the column 1. 2) The extent of SR ratio which is confined in the safety allowance of 30 percent is shown in the column 2. 3) The lowest limitation of SR ratio which gives the most danger probability of 100 percent is shown in column 3. In analyzing above results, it is clear that chestnut and larch easly form internal stress in comparison with persimmon and pine. However, in considering the fact that the revers, casehardening occured in fir and ginkgo, under the same drying condition with the others, it is deduced that fir and ginkgo form normal casehardening with difficulty in comparison with the other species tested. 5. All kinds of drying defects except casehardening are developed when the internal stresses are in excess of the ultimate strength of material in the case of long-lime loading. Under the drying condition at temperature of $170^{\circ}F$ and the lower humidity. the drying defects are not so severe. However, under the same conditions at $200^{\circ}F$, the lower humidity and not end coated, all sample boards develop severe drying defects. Especially the chestnut was very prone to form the drying defects such as casehardening and splitting.

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Outer Space Activities and an Observation of Related Laws of Korea (국내 우주활동과 관련법 소고)

  • Park, Won-Hwa
    • The Korean Journal of Air & Space Law and Policy
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    • v.24 no.2
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    • pp.163-186
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    • 2009
  • The missile technology and its development in south Korea have been restrained to the limit of 180 km by America which instead provided to Korea with security protection. In the same vein, America pressured South Korea to abort its nuclear weapons program so as to prevent another possible military encounter that can easily develop into a war between South and North Korea. This restraint was a bit relaxed when South Korea joined the Missile Technology Control Regime (MTCR) in 2001 whereby the limit was 300 km. The situation of South Korea is in much contrast with its neighbor, North Korea, which has fired Taepo Dong 1 and Taepo Dong 2 to put its alleged satellite respectively into the Earth orbit. The range of this rocket believed to be reaching more than 5,500 km, a range of the intercontinental ballistic missile, without any rein. South Korea that has just geared its full powers for its outer space industry, with the current space projects of putting its satellites into the low Earth orbit, will in future put its satellite into the geostationary orbit, 36,000 km above the Earth. To do so, such restraint had better be resolved. Korean space industry, as it is alike in other countries, started with putting and manufacturing sounding rockets, producing satellites but relying on foreign launching facilities, and learning launching capacities. Experiencing three time launchings of KITSAT, the current satellite projects of Korea are undertaken as follows: - Koreasat - STSAT - Komsat - MBSAT - COMS (Communication, Ocean, and Meteorological Satellite) Koreans waked up to the things of outer space in 2008 with the first Korean astronaut Li So-yeon, a lady bio systems engineer. Although the first Korean made rocket in cooperation with a Russian company to fire last August 2009 was a failure, it should be considered as an inevitable process for future endeavors. There are currently three outer space related laws of Korea: Aerospace Industry Development Promotion Act 1987, Outer Space Development Promotions Act 2005, and Space Damage Compensation Act 2008. The first two stemming from the two different ministries are, however, overlapping in many aspects and have some shortcomings to be improved.

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Arsenic Contamination of Polished Rice Produced in Abandoned Mine Areas and Its Potential Human Risk Assessment using Probabilistic Techniques (폐광지역에서 생산된 백미 중 비소오염도와 확률론적 기법을 이용한 인체 위해성 평가)

  • Lee, Ji-Ho;Kim, Won-Il;Jeong, Eun-Jung;Yoo, Ji-Hyock;Kim, Ji-Young;Paik, Min-Kyung;Park, Byung-Jun;Im, Geon-Jae;Hong, Moo-Ki
    • Korean Journal of Environmental Agriculture
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    • v.30 no.1
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    • pp.43-51
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    • 2011
  • BACKGROUND: This study was conducted to investigate the arsenic (As) contaminations in polished rice cultivated nearby abandoned mine areas, and to estimate the potential health risk through dietary intake of As-enriched polished rice in each age-gender population. METHODS AND RESULTS: The As contents in polished rice grown fifteen abandoned mine areas were analyzed. The average daily intake (ADD) as well as probabilistic health risk were estimated by assuming probability distribution of exposure parameters. The average total As concentration in polished rice was $0.09{\pm}0.06$ mg/kg with a range of 0.02~0.35 mg/kg. For health risk assessment, the ADD values in all age-gender populations did not exceed the provisional tolerable daily intake (PTDI) of 2.1 ${\mu}g/kg$ b.w./day for inorganic As. Cancer risk probability (R) values were $2.45{\sim}3.28{\times}10^{-4}$ and $2.51{\sim}5.75{\times}10^{-4}$ for all age population and gender population, respectively. Particularly, the R value, $5.75{\times}10^{-4}$, for children less than six years old were estimated to be high. Hazard quotient (HQ) values were 0.23~0.31 and 0.11~0.33 for general population and age-gender population, respectively. CONCLUSION(s): The average R values assessed via intake of polished rice cultivated in abandoned mine areas exceeded the acceptable cancer risk of $10^{-6}{\sim}10^{-4}$ for regulatory purpose. Considering the HQ values smaller than 1.0, potential non-cancer toxic effects may not be caused by the long-time exposure through intake of As-contaminated polished rice.

Residual characteristic of tebuconazole and fludioxonil in Allium victorialis (Allium ochotense Prokh.) (소면적 재배작물 산마늘(Allium ochotense Prokh.) 중 살균제 Tebuconazole 및 Fludioxonil의 잔류특성)

  • Woo, Min-Ji;Hur, Kyung-Jin;Kim, Ji-Yoon;Saravanan, Manoharan;Kim, Se-Weon;Hur, Jang-Hyeon
    • The Korean Journal of Pesticide Science
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    • v.19 no.4
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    • pp.354-360
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    • 2015
  • In recent years, Allium victorialis has been extensively used as a pharmacological agent for various diseases in the form of anti-arteriosclerotic, anti-diabetic and anti-cancer. Allium victorialis is severely affected by various fungal diseases since it naturally grow in the shady and humid environments in Korea. In this case, different types of fungicides are applied to control the fungal diseases in Allium victorialis. The present study was aimed to determine the residual characteristics of two fungicides namely tebuconazole and fludioxonil on Allium victorialis. For this study, the fungicides were drenched soil on Allium victorialis in the cultivation area Pyeongchang by the standard (two thousand fold) and double (thousand fold) dilutions. At the end of $15^{th}$, $30^{th}$ and $40^{th}$ days samples were collected for residue analysis. Residues of tebuconazole and fludioxonil were analyzed using GC/NPD (Gas Chromatography/Nitrogen Phosphorus Detector) and their recovery were found to be 108.8~119.5% and 91.3~104.8%, respectively. The method of limits of quantification for both fungicides was $0.01mg\;kg^{-1}$. Further, the results of this study shows that the residue levels of both fungicides on Allium victorialis were <$0.01{\sim}0.12mg\;kg^{-1}$ and $0.01{\sim}0.09mg\;kg^{-1}$ and their % ADI (% Acceptable Daily Intake) were 17.44% and 25.75%, respectively. Based on the results obtained in this study, we suggest that the residue levels of both of the fungicides on Allium victorialis are safe and these fungicides can also be used to control fungal diseases in Allium victorialis.

Study on Ventilation Efficiency of a Mechanically Ventilated Broiler House­(I)Summer Season (강제환기식 육계사내의 환기효율성 조사연구­(I)하절기)

  • 이인복;정문성;유병기;전종기;김경원;이승기
    • Journal of Animal Environmental Science
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    • v.9 no.2
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    • pp.103-112
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    • 2003
  • In this study, the distributions of internal climates such as air temperature, humidity, dust, ammonia gas, and air velocity were systematically measured at a mechanically ventilated broiler houses during summer season, with local weather data. The analysis was focused on the suitability, stability, and uniformity of internal climate, resulting in serious stress on chickens and decrease of productivity In the mechanically ventilated broiler house, the difference between measured and recommended air temperatures(suitability) was 10.4C in maximum during the summer time. The difference of air temperature in the house between day and night was $8.7^{\circ}C$ in maximum. And maximal hourly range of internal air temperature at 0.4m height from the floor was $3.7^{\circ}C$ suggesting it maintained thermal uniformity in the broiler house. The $NH_3$ and dust concentrations were pretty low because ventilation was fully performed. The air speed at chicken location was measured 2.2m/s and 1.7m/s, respectively without and with chicken existence.

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Right-Turn Vehicle Supplementary Signal Improvement at Intersections (교차로 우회전 차량 보조등 개선)

  • LEE, Nam Soo;KIM, Yu Chan;LIM, Joon Beom;KIM, Youngchan
    • Journal of Korean Society of Transportation
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    • v.33 no.5
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    • pp.441-448
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    • 2015
  • This study aims to suggest a reasonable signal operation method for right-turn traffic management. It was found that the right-turn vehicle supplementary signal is currently operated without clear regulations or criteria. It was also analyzed that right-turn supplementary signals are used without consistency, there is a risk of traffic accidents due to the discordance between supplementary signals and traffic signals of forward vehicles, there is a lack of basis for prohibition of a right turn when right-turn vehicle's supplementary signal is red and the flashing red signal is used in a different sense from the law. In order to see the effect of the installed right-turn vehicle supplementary signals on traffic signal violation, a field investigation was conducted. As the result, there was a high proportion of signal violation on the approach lane with right-turn supplementary signals and this means that right-turn supplementary signals hardly influenced the reduction in proportion of signal violation during a right turn. Additionally, a survey was carried out to see if there were differences in driver's interpretation of traffic signals depending on the installation of right-turn supplementary signals. As the result of the survey, there were no differences in interpretation of traffic signals depending on the installation of right-turn supplementary signals or the types of right-turn supplementary signals. A right turn when the signal was red did not lead to serious traffic accidents, so it is thought that there should be a careful consideration of a total ban on a right turn when the signal is red, in order to prevent driver's confusion due to the change of the signal system. Unless there is a disturbance to cars and pedestrians after a temporary stop when the signal is red, there is a need to specify that vehicles must stop temporarily in the Road Traffic Act to facilitate a right turn. What this study finally suggested is to use tri-colored arrow signals for right-turn car supplementary signals to convey a signal to a driver clearly.