• Title/Summary/Keyword: safety engineering

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Evaluation of the Simulated PM2.5 Concentrations using Air Quality Forecasting System according to Emission Inventories - Focused on China and South Korea (대기질 예보 시스템의 입력 배출목록에 따른 PM2.5 모의 성능 평가 - 중국 및 한국을 중심으로)

  • Choi, Ki-Chul;Lim, Yongjae;Lee, Jae-Bum;Nam, Kipyo;Lee, Hansol;Lee, Yonghee;Myoung, Jisu;Kim, Taehee;Jang, Limseok;Kim, Jeong Soo;Woo, Jung-Hun;Kim, Soontae;Choi, Kwang-Ho
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.2
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    • pp.306-320
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    • 2018
  • Emission inventory is the essential component for improving the performance of air quality forecasting system. This study evaluated the simulated daily mean $PM_{2.5}$ concentrations in South Korea and China for 1-year period (Sept. 2016~Aug. 2017) using air quality forecasting system which was applied by the emission inventory of E2015 (predicted CAPSS 2015 for South Korea and KORUS 2015 v1 for the other regions). To identify the impacts of emissions on the simulated $PM_{2.5}$, the emission inventory replaced by E2010 (CAPSS 2010 and MIX 2010) were also applied under the same forecasting conditions. These results showed that simulated daily mean $PM_{2.5}$ concentrations had generally suitable performance with both emission data-sets for China (IOA>0.87, R>0.87) and South Korea (IOA>0.84, R>0.76). The impacts of the changes in emission inventories on simulated daily mean $PM_{2.5}$ concentrations were quantitatively estimated. In China, normalized mean bias (NMB) showed 5.5% and 26.8% under E2010 and E2015, respectively. The tendency of overestimated concentrations was larger in North Central and Southeast China than other regions under both E2010 and E2015. Seasonal differences of NMB were higher in non-winter season (28.3% (E2010)~39.3% (E2015)) than winter season (-0.5% (E2010)~8.0% (E2015)). In South Korea, NMB showed -5.4% and 2.8% for all days, but -15.2% and -11.2% for days below $40{\mu}g/m^3$ to minimize the impacts of long-range transport under E2010 and E2015, respectively. For all days, simulated $PM_{2.5}$ concentrations were overestimated in Seoul, Incheon, Southern part of Gyeonggi and Daejeon, and underestimated in other regions such as Jeonbuk, Ulsan, Busan and Gyeongnam, regardless of what emission inventories were applied. Our results suggest that the updated emission inventory, which reflects current status of emission amounts and spatio-temporal allocations, is needed for improving the performance of air quality forecasting.

The research for the yachting development of Korean Marina operation plans (요트 발전을 위한 한국형 마리나 운영방안에 관한 연구)

  • Jeong Jong-Seok;Hugh Ihl
    • Journal of Navigation and Port Research
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    • v.28 no.10 s.96
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    • pp.899-908
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    • 2004
  • The rise of income and introduction of 5 day a week working system give korean people opportunities to enjoy their leisure time. And many korean people have much interest in oceanic sports such as yachting and also oceanic leisure equipments. With the popularization and development of the equipments, the scope of oceanic activities has been expanding in Korea just as in the advanced oceanic countries. However, The current conditions for the sports in Korea are not advanced and even worse than underdeveloped countries. In order to develop the underdeveloped resources of Korean marina, we need to customize the marina models of advanced nations to serve the specific needs and circumstances of Korea As such we have carried out a comparative analysis of how Austrailia, Newzealand, Singapore, japan and Malaysia operate their marina, reaching the following conclusions. Firstly, in marina operations, in order to protect personal property rights and to preserve the environment, we must operate membership and non-membership, profit and non-profit schemes separately, yet without regulating the dress code entering or leaving the club house. Secondly, in order to accumulate greater value added, new sporting events should be hosted each year. There is also the need for an active use of volunteers, the generation of greater interest in yacht tourism, and the simplification of CIQ procedures for foreign yachts as well as the provision of language services. Thirdly, a permanent yacht school should be established, and classes should be taught by qualified instructors. Beginners, intermediary, and advanced learner classes should be managed separately with special emphasis on the dinghy yacht program for children. Fourthly, arrival and departure at the moorings must be regulated autonomically, and there must be systematic measures for the marina to be able, in part, to compensate for loss and damages to equipment, security and surveillance after usage fees have been paid for. Fifthly, marine safety personnel must be formed in accordance with Korea's current circumstances from civilian organizations in order to be used actively in benchmarking, rescue operations, and oceanic searches at times of disaster at sea.

Relationship between Compressive Strength and Dynamic Modulus of Elasticity in the Cement Based Solid Product for Consolidating Disposal of Medium-Low Level Radioactive Waste (중·저준위 방사성 폐기물 처리용 시멘트 고화체의 압축강도와 동탄성계수의 관계)

  • Kim, Jin-Man;Jeong, Ji-Yong;Choi, Ji-Ho;Shin, Sang-Chul
    • Journal of the Korea Concrete Institute
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    • v.25 no.3
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    • pp.321-329
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    • 2013
  • Recently, the medium-low level radioactive waste from nuclear power plant must be transported from temporary storage to the final repository. Medium-low level radioactive waste, which is composed mainly of the liquid ion exchange resin, has been consolidated with cementitious material in the plastic or iron container. Since cementitious material is brittle, it would generate cracks by impact load during transportation, signifying leakage of radioactive ray. In order to design the safety transporting equipment, there is a need to check the compressive strength of the current waste. However, because it is impossible to measure strength by direct method due to leakage of radioactive ray, we will estimate the strength indirectly by the dynamic modulus of elasticity. Therefore, it must be identified the relationship between of strength and dynamic modulus of elasticity. According to the waste acceptance criteria, the compressive strength of cement based solid is defined as more than 3.44 MPa (500 psi). Compressive strength of the present solid is likely to be significantly higher than this baseline because of continuous hydration of cement during long period. On this background, we have tried to produce the specimens of the 28 day's compressive strength of 3 to 30 MPa having the same material composition as the solid product for the medium-low level radioactive waste, and analyze the relationship between the strength and the dynamic modulus of elasticity. By controling the addition rates of AE agent, we made the mixture containing the ion exchange resin and showing the target compressive strength (3~30 MPa). The dynamic modulus of elasticity of this mixtures is 4.1~10.2 GPa, about 20 GPa lower in the equivalent compressive strength level than that of ordinary concrete, and increasing the discrepancy according to increase strength. The compressive strength and the dynamic modulus of elasticity show the liner relationship.

Application Effect of Heating Energy Saving Package on Venlo Type Glasshouse of Paprika Cultivation (파프리카 재배 벤로형 유리온실에서 난방에너지 절감 패키지 기술 적용효과)

  • Kwon, Jin Kyung;Jeon, Jong Gil;Kim, Seung Hee;Kim, Hyung Gweon
    • Journal of Bio-Environment Control
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    • v.25 no.4
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    • pp.225-231
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    • 2016
  • Glasshouse heating package technologies to improve energy usage efficiency in winter were developed. Heating package was composed of the ground water source heat pump with heating capacity of 105kW, the aluminum multi-layer thermal curtain with six layers of different materials and the root zone local heater with XL pipes of ${\phi}20mm$. Venlo type glasshouse($461m^2$) with the heating package was compared with the same type and area control glasshouse with the light oil boiler, the usual non-woven fabric thermal curtain with respect to the glasshouse inside temperature, relative humidity, crop growth, and heating energy consumption. The results of test in paprika cultivation glasshouses showed that the air temperature inside glasshouse with aluminum multi-layer thermal curtain was maintained $2.2^{\circ}C$ higher than that of control glasshouse in un-heating night time and the temperature in bed with root zone local heating was $4.7^{\circ}C$ higher than that in bed without local heating. Average heating coefficient of performance(COP) of the ground water source heat pump used in paprika cultivation was 3.7 and the glasshouse inside temperature was maintained at $21^{\circ}C$ of heating set up temperature. The heating energy consumptions per 10a were measured at 14,071L of light oil and 364kWh of electric power for the control glasshouse and 35,082kWh for the glasshouse applied heating package. As results, the heating cost of the glasshouse applied heating package was 87 percent lower than that of control glasshouse. The growths of paprika in glasshouses of control and applied heating package did not show any significant difference.

Improvement of Heat Pump Heating Performance by Selective Heat Storage Using Air Heat of Inside and Outside Greenhouse (온실 내외부 공기열의 선택적 축열에 의한 히트펌프 난방성능 개선)

  • Kwon, Jin Kyung;Kim, Seung Hee;Jeon, Jong Gil;Kang, Youn Koo;Jang, Kab Yeol
    • Journal of Bio-Environment Control
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    • v.26 no.4
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    • pp.353-360
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    • 2017
  • In this study, the design and performance test of the air to water heat pump capable of producing hot water for greenhouse heating by using the surplus solar heat inside the greenhouse and the air heat outside greenhouse as the selective heat source were conducted. The heat storage operations using the surplus solar heat and the outside air heat were designed to be switched according to the setting temperature of the greenhouse in consideration of the optimum temperature range of the crop. In the developed system, it was possible to automatically control the switching of heat storage operation, heating and ventilation by setting 12 reference temperatures on the control panel. In the selective heat storage operation with the surplus solar heat and outside air heat, the temperature of thermal storage tank was controlled variably from $35^{\circ}C$ to $52^{\circ}C$ according to the heat storage rate and heating load. The heat storage operation times using the surplus solar heat and outside air heat were 23.1% and 30.7% of the experimental time respectively and the heat pump pause time was 46.2%. COP(coefficient of performance) of the heat pump of the heat storage operation using the surplus solar heat and outside air heat were 3.83 and 2.77 respectively and was 3.24 for whole selective heat storage operation. For the comparative experiment, the heat storage operation using the outside air heat only was performed under the condition that the temperature of the thermal storage tank was controlled constantly from 50 to $52^{\circ}C$, and COP was analyzed to be 2.33. As a result, it was confirmed that the COP of the heat storage operation using the surplus solar heat and outside air heat as selective heat source and the variable temperature control of the thermal storage tank was 39% higher than that of the general heat storage operation using the outside air heat only and the constant temperature control of the thermal storage tank.

A Study on the Fatigue Strength of the Welded Joints in Steel Structures(II) (강구조물(鋼構造物)의 용접연결부(鎔接連結部)의 피로강도(疲勞强度)에 관한 연구(研究)(II))

  • Park, Je Seon;Chung, Yeong Wha;Chang, Dong Il
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.6 no.1
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    • pp.1-11
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    • 1986
  • Welded connectors of the cover plates, the transverse stiffeners of the plate girders, and the gusset plates of the plates girders or box girders, were selected as studying objects. A simplified method of drawing the S-N curves in these welded joints by a computer program without the direct fatigue tests was established. The plots on the S-N curve using the values from the practical fatigue tests were compared with the results from the method of the computer programming. The results of these studies are as follows. It appeared that the fatigue life by calculation method was a little less than the practical fatigue life from the actual tests. The latter values included both life $N_c$ of occurrence of initial crack $a_i$ and the life $N_p$ of propagation of critical crack. On the other hand, the former values included only the life $N_p$. Therefore, these results should be considered as justifiable ones. Since the difference between the two results was not significant, the results by calculation method should be in the conservation side when the safety of the structures was considered. Consequently, the results by calculation method should be applicable to the fracture fatigue design of structure. For reference, the same fatigue tests were performed with the specimens of 3 pieces in each case made of the low-strength steel, SS 41. The results went unexpected showing that the fatigue strength was lower in the case of low-strength steel. That is, in the case of the cover plate, the fatigue strength became slowly higher than the case of high-strength steel, SWS 50. That was observed when the maximum testing stress was higher than $14kg/mm^2$. In addition, in the case of the transverse stiffener, the fatique strength became rapidly higher than the case of SWS 50. That was observed when the maximum testing stress was lower than $31kg/mm^2$. It was thought that more such fatigue tests should be performed for more reliable results.

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A Study on LRFD Reliability Based Design Criteria of RC Flexural Members (R.C. 휨부재(部材)의 L.R.F.D. 신뢰성(信賴性) 설계기준(設計基準)에 관한 연구(研究))

  • Cho, Hyo Nam
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.1 no.1
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    • pp.21-32
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    • 1981
  • Recent trends in design standards development in some European countries and U.S.A. have encouraged the use of probabilistic limit sate design concepts. Reliability based design criteria such as LSD, LRFD, PBLSD, adopted in those advanced countries have the potentials that they afford for symplifying the design process and placing it on a consistent reliability bases for various construction materials. A reliability based design criteria for RC flexural members are proposed in this study. Lind-Hasofer's invariant second-moment reliability theory is used in the derivation of an algorithmic reliability analysis method as well as an iterative determination of load and resistance factors. In addition, Cornell's Mean First-Order Second Moment Method is employed as a practical tool for the approximate reliability analysis and the derivation of design criteria. Uncertainty measures for flexural resistance and load effects are based on the Ellingwood's approach for the evaluation of uncertainties of loads and resistances. The implied relative safety levels of RC flexural members designed by the strength design provisions of the current standard code were evaluated using the second moment reliability analysis method proposed in this study. And then, resistance and load factors corresponding to the target reliability index(${\beta}=4$) which is considered to be appropriate level of reliability considering our practices are calculated by using the proposed methods. These reliability based factors were compared to those specified by our current ultimate strength design provisions. It was found that the reliability levels of flexural members designed by current code are not appropriate, and the code specified resistance and load factors were considerably different from the reliability based resistance and load factors proposed in this study.

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Application of the Pulsatile Cardiopulmonary Bypass in Animal Model (이중 박동성 인공심폐기의 동물 실험)

  • Shin, Hwa-Kyun;Won, Yong-Soon;Lee, Jea-Yook;Her, Keun;Yeum, Yook;Kim, Seung-Chul;Min, Byoung-Goo
    • Journal of Chest Surgery
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    • v.37 no.1
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    • pp.1-10
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    • 2004
  • Background: Currently, the cardiopulmonary machine with non-pulsatile pumps, which are low in internal circuit pressure and cause little damage to blood cells, is widely used. However, a great number of experimental studies shows that pulsatile perfusions are more useful than non-pulsatile counterparts in many areas, such as homodynamic, metabolism, organ functions, and micro-circulation. Yet, many concerns relating to pulsatile cardiopulmonary machines, such as high internal circuit pressure and blood cell damage, have long hindered the development of pulsatile cardiopulmonary machines. Against this backdrop, this study focuses on the safety and effectiveness of the pulsatile cardiopulmonary machines developed by a domestic research lab. Material and Method: The dual-pulsatile cardiopulmonary bypass experiment with total extracorporeal circulation was conducted on six calves, Extracorporeal circulation was provided between superior/inferior vena cava and aorta. The membrane oxygenator, which was placed between the left and right pumps, was used for blood oxygenation. Circulation took four hours. Arterial blood gas analysis and blood tests were also conducted. Plasma hemoglobin levels were calculated, while pulse pressure and internal circuit pressure were carefully observed. Measurement was taken five times; once before the operation of the cardiopulmonary bypass, and after its operation it was taken every hour for four hours. Result: Through the arterial blood gas analysis, PCO2 and pH remained within normal levels. PO2 in arterial blood showed enough oxygenation of over 100 mmHg. The level of plasma hemoglobin, which had total cardiopulmonary circulation, steadily increased to 15.87 $\pm$ 5.63 after four hours passed, but remained below 20 mg/㎗. There was no obvious abnormal findings in blood test. Systolic blood pressure which was at 97.5$\pm$5.7 mmHg during the pre-circulation contraction period, was maintained over 100 mmHg as time passed. Moreover, diastolic blood pressure was 72.2 $\pm$ 7.7 mmHg during the expansion period and well kept at the appropriate level with time passing by. Average blood pressure which was 83$\pm$9.2 mmHg before circulation, increased as time passed, while pump flow was maintained over 3.3 L/min. Blood pressure fluctuation during total extracorporeal circulation showed a similar level of arterial blood pressure of pre-circulation heart. Conclusion: In the experiment mentioned above, pulsatile cardiopulmonary machines using the doual-pulsatile structure provided effective pulsatile blood flow with little damage in blood cells, showing excellence in the aspects of hematology and hemodynamic. Therefore, it is expected that the pulsatile cardiopulmonary machine, if it becomes a standard cardiopulmonary machine in all heart operations, will provide stable blood flow to end-organs.

Multiple Monoclonal Antibodies Produced in a Single Transgenic Plant (형질전환 식물체에서의 복합 단일 항체 단백질 생산)

  • Ahn, Mi-Hyun;Oh, Eun-Yi;Song, Mi-Ra;Lu, Zhe;Kim, Hyun-Soon;Joung, Hyouk;Ko, Ki-Sung
    • Journal of Life Science
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    • v.19 no.1
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    • pp.123-128
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    • 2009
  • Production of highly valuable immunotherapeutic proteins such as monoclonal antibodies and vaccines using plant biotechnology and genetic engineering has been studied as a popular research field. Plant expression system for mass production of such useful recombinant therapeutic proteins has several advantages over other existing expression systems with economical and safety issues. Immunotherapy of multiple monoclonal antibodies, which can recognize multiple targeting including specific proteins and their glycans highly expressed on the surface of cancer cells, can be an efficient treatment compared to a single targeting immunotherapy using a single antibody. In this study, we have established plant production system to express two different targeting monoclonal antibodies in a single transgenic plant through crossing fertilization between two different transgenic plants expressing anti-colorectal cancer mAbCO17-1A and anti-breast cancer mAbBR55, respectively. The F1 seedlings were obtained cross fertilization between the two transgenic parental plants. The presence, transcription, and protein expression of heavy chain (HC) and light chain (LC) genes of both mAbs in the seedlings were investigated by PCR, RT-PCR, and immunoblot analyses, respectively. Among all the seedlings, some seedlings did not carry or transcribe the HC and LC genes of both mAbs. Thus, the seedlings with presence and transcription of HC and LC genes of both mAbs were selected, and the selected seedlings were confirmed to have relatively stronger density of HC and LC protein bands compared to the transgenic plant expressing only each mAb. These results indicate that the F1 seedling plant with carrying both mAb genes was established. Taken together, plant crossing fertilization can be applied to generate an efficient production system expressing multiple monoclonal antibodies for immunotherapy in a single plant.

Evaluation of Indoor Air Quality in a Department of Radiation Oncology Located Underground (지하에 위치한 방사선종양학과에서의 실내공기 질 평가)

  • Kim, Won-Taek;Shin, Yong-Chul;Kang, Dong-Mug;Ki, Yong-Kan;Kim, Dong-Won;Kwon, Byung-Hyun
    • Radiation Oncology Journal
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    • v.23 no.4
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    • pp.243-252
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    • 2005
  • Purpose: Indoor air quality (IAQ) in the radiation treatment center which is generally located underground is important to the health of hospital workers and patients treated over a long period of time. this study was conducted to measure and analyze the factors related to IAQ and subjective symptoms of sick building syndrome, and to establish the causes influencing IAQ and find a solution to the problems. Methods and Materials : Self administrated questionnaire was conducted to check the workers' symptoms and understanding of the work environment. Based on a preliminary investigation, the factors related to IAQ such as temperature, humidity, fine particulate. carbon dioxide, carbon monoxide, formaldehyde, total volatile organic compounds (TVOC), and radon gas were selected and measured for a certain period of time in specific sites where hospital workers stay long in a day. And we also evaluated the surrounding environment and the efficiency of the ventilating system simultaneously, and measured the same factors at the first floor (outdoor) to compare with outdoor all quality, All collected data were assessed by the recommended standard for IAQ of the domestic and international environmental organizations. Results: Hospital workers were discontented with foul odors, humidity and particulate. They complained symptoms related to musculo-skeletal system, neurologic system, and mucosal-irritatation. Most of the factors were not greater than the recommended standard, but the level of TVOC was third or fourth times as much as the measuring level of some offices in the United States. The frequency and the amount of the ventilating system were adequate, however, the problem arising in the position of outdoor-air inlets and indoor-air outlets involved a risk of the indraft of contaminated air. A careful attention was a requirement in handling and keeping chemical substances including a developing solution which has a risk of TVOC emissions, and repositioning the ventilating system was needed to solve the contaminated-air circulation immediately Conclusion We verified that some IAQ-related factors and inadequate ventilating system could cause subjective symptoms in hospital workers. The evaluation of IAQ was surely needed to improve the underground working environments for hospital workers and patients. On the basis of these data, from now on, we should actively engage in designs of the department of radiation oncology or improvement in environments of the existing facilities.