• 한국대기환경학회지
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• 제25권1호
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• pp.38-45
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• 2009

Since the seventies and the oil crisis, energy-saving measures have led to a reduction in the ventilation of room. The use of synthetic materials which emit various chemical substances had led to an increase in the concentration of indoor pollutants. "Sick building syndrome (SBS)" and "Sick house syndrome (SHS)" are worldwide problems. Also, the number of complaints about indoor air pollution caused by VOCs (Volatile organic compound) and HCHO (Formaldehyde) has increased. It is important that evaluating and understanding emission of indoor air pollutant from building materials. The object of this study was to evaluate emission test method for flooring such as wood based flooring, carpet tile, rubber tile, PVC sheet and tile, and to determine emission of TVOC and form-aldehyde. The quantity of TVOC and carbonyl compounds emission were sampled and measured by Tenax TA and gas chromatography/mass spectrometry (GC/MSD), 2,4-DNPH cartrige with ozone scrubber and high performance liquid from flooring. The TVOC concentration emitted from carpet tile was ($7.419\;mg/m^2 h$) the highest among 5 groups of test materials. In wood based flooring and PVC tile, the emitted concentration of toluene was high. And the dodecane emission was highest in carpet. The concentration of TVOC decreased by an increase in emission test period. After 7 days, the concentration of TVOC from floorings were about 50% below of the concentration at the first day. TVOC emission from wood based flooring, carpet tile, rubber tile, PVC sheet and tile were decreased in 28 days and remained steady after about 15 days. The concentration of formaldehyde emission from floorings showed extremely low.

• 한국분무공학회지
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• 제11권4호
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• pp.251-265
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• 2006

To prevent the ozonosphere from being destroyed by Halon, it is an urgent task to find out Halon replacement. As one of the replacements water mist have showed broad applications by its advantages: little pollution to environment (not destroying the ozone layer or bring green house effect), extinguishing fire quickly, consuming a small quantity of water and having little damage to the protected objects. The methods of generating water mist strongly influence fire suppression effectiveness, which determine the cone angle, drop size distribution, flux uniformity, and momentum of the generating spray. The traditional water mist nozzle included pressure jet nozzles, impingement nozzles and twin-fluid nozzles. All of them have more or less disadvantages for fire suppression. Therefore, many research institutes and corporations are taking up with innovations in mist generation. This article provided some recent studies in State Key Laboratory of Fire Science (SKLFS) of University of Science and Technology of China. SKLFS have investigated new methods of generating water mist (i.e. effervescent atomization and ultrasonic atomization). and self developed a series of nozzles and developed advanced DPIVS (Digital Particle Image Velocimetry and Sizing) technique. Characteristics of water mist (the distribution of droplet sizes, flux density, spray dynamics and cone angle) produced by these nozzles were measured under different conditions (work pressure, nozzle geometry, etc.) using LDV/APV and DPTVS systems. A series of experiments were performed to study the fire suppression effectiveness in different fire scenario (different kindsof the fuel, fire size and ventilation conditions). The fire extinguishing mechanisms of water mist was also discussed.

• 상하수도학회지
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• 제25권6호
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• pp.885-892
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• 2011

In this study, LCA(Life Cycle Assessment) on 'Saemangum CSO Project' was carried out to evaluate environmental impact which occurred during the construction and operation periods and the potential environmental impact reduction was analyzed by comparing production and reduction level of pollution loads. LCA was conducted out according to the procedure of ISO14040 which suggested Goal and Scope Definition, Life Cycle Inventory Analysis, Life Cycle Impact Assessment and Interpretation. In the Goal and Scope Definition, the functional unit was 1 m3 of CSO, the system boundary was construction and operation phases, and the operation period was 20 years. For the data collection and inventory analysis, input energies and materials from civil, architecture, mechanical and electric fields are collected from design sheet but the landscape architecture field is excepted. LCIA(Life Cycle Impact Assessment) was performed following the procedure of Eco-Labelling Type III under 6 categories which were resource depletion, eutrophication, global warming, ozone-layer destruction, and photochemical oxide formation. In the result of LCA, 83.4% of environmental impact occurred in the construction phase and 16.6% in the operation phase. Especially 78% of environmental impact occurred in civil works. The Global warming category showed the highest contribution level in the environmental impact categories. For the analysis on potential environmental impact reduction, the reduction and increased of environmental impact which occurred on construction and operation phases were compared. In the case of considering only the operation phase, the result of the comparison showed that 78% of environmental impact is reduced. On the other hand, when considering both the construction and operation phases, 50% of environmental impact is increase. Therefore, this study showed that eco-friendly material and construction method should be used for reduction of environmental impact during life cycle, and it is strongly necessary to develop technology and skills to reduce environmental impact such as renewable energies.

• 동굴
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• 제76호
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• pp.37-42
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• 2006

The Dielectric Barrier Discharge (DBD) is a nonequilibrium gas discharge that is generated in the space between two electrodes, which are separated by an insulating dielectric layer. The dielectric layer can be put on either of the two electrodes or be inserted in the space between two electrodes. If an AC or pulse high voltage is applied to the electrodes that is operated at applied frequency from 50Hz to several MHz and applied voltages from a few to a few tens of kilovolts rms, the breakdown can occur in working gas, resulting in large numbers of micro-discharges across the gap, the gas discharge is the so called DBD. Compared with most other means for nonequilibrium discharges, the main advantage of the DBD is that active species for chemical reaction can be produced at low temperature and atmospheric pressure without the vacuum set up, it also presents many unique physical and chemical process including light, heat, sound and electricity. This has led to a number of important applications such as ozone synthesizing, UV lamp house, CO2 lasers, et al. In recent years, due to its potential applications in plasma chemistry, semiconductor etching, pollution control, nanometer material and large area flat plasma display panels, DBD has received intensive attention from many researchers and is becoming a hot topic in the field of non-thermal plasma.

• 한국물환경학회지
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• 제24권5호
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• pp.537-542
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• 2008

Textile industry has been recognized as an important pollution source due to its consumption of large volumes of water and chemicals. Textile wastewater contains very diverse chemicals in types and composition, among them the presence of dyes is highly visible and undesirable. In spite of these problems, there has not been a proper control for the wastewater because many dyes are difficult to be degraded or decolorized due to their complex structure and synthetic characteristics. This study has been progressed to evaluate more easily the potential decolorization of advanced treatment processes. It has been surveyed with the Y textile complex wastewater treatment plant, the raw wastewater has appeared very difficult biodegradability by 4.7 of $CODcr/BOD_5$ and 1,158.9 degree of color. In view of CODcr fractions, biodegradable COD portion was 46.4%, colloidal COD and real soluble COD was 45.3% and 31.5% each others. From research on unit processes, the degradable coefficient (k) became from 0.065 to $0.125d^{-1}$ by the processes, the decolorization appeared best efficiency by 30.1% (458.4 degree) in pre-ozone process. On the effluent from the biological process, the filterable CODcr became 129.3 mg/L, the biodegradable portion appeared 64.7% (83.6 mg/L), and the fixed dissolved solid (FDS), non-reactivity (NR), appeared very heavy portion by 80.5% (1,659.0 mg/L).

• 통상정보연구
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• 제15권1호
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• pp.97-116
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• 2013

최근 들어 이런 환경문제와 관련된 가장 큰 특징은 선진국들을 중심으로 무역과 환경을 연계시키려는 움직임이 나타나고 있다는 것이다. 기후변화협약체제는 단순히 환경문제에만 국한되지 않는다. 경제활동에 있어 주요 동력원인 화석연료에 대한 규제는 곧 생산활동에 대한 규제로 직결되기 때문에 경제 및 무역에 미치는 영향은 지대한 것이다. 우리나라는 무역의존도가 매우 높으나 환경기준은 선진국에 비해 매우 낮기 때문에 환경문제가 무역과 연계가 강화된다면 우리나라 경제는 상당히 악영향을 받을 수밖에 없을 것이다. 따라서 본 논문에서는 기후변화협약체제가 무역에 미칠 수 있는 영향을 살펴보고, 우리나라의 대응방안을 체계적으로 수립하는데 목적이 있다. 이러한 목적을 위하여 무역과 환경문제와의 상호관계를 살펴보고, 기후변화협약과 교토의정서의 무역관련 연계에 관해 분석하여 우리나라의 대응방안을 제시하고자 한다.

• 실내환경 및 냄새 학회지
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• 제16권3호
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• pp.277-286
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• 2017

The objectives of this study were to investigate the effects of $PM_{10}$ and $O_3$ concentration on the symptoms of allergic diseases. The questionnaire was used to determine whether or not symptoms of allergic diseases were present from September to October 2012. The air pollution concentration data used was the corresponding point CEM (continuous emission monitoring) data. The average concentration of $PM_{10}$ was $56.09{\mu}g/m^3$ in the control area, and the concentration in the exposed area was $40.44{\mu}g/m^3$. In the two areas, concentration of $O_3$ was 28.73 ppb and 28.74 ppb, respectively. The total average concentrations of $PM_{10}$ and $O_3$ were $45.66{\mu}g/m^3$ and 28.73 ppb in the Gwangyang area. The rate of asthma diagnosis was higher in the control area (9.6%) than in the exposed area (4.1%), but the rate of allergy eye disease was higher in the exposed area (23.9%) than in the control area (16.5%). There was a significant difference in the symptoms of some allergic diseases when the relative concentration of $PM_{10}$ and $O_3$ were high and low.

• Journal of Dental Anesthesia and Pain Medicine
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• 제24권1호
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• pp.67-73
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• 2024

Background: Nitrous oxide has been an integral part of surgical anesthesia for many years in the developed world and is still used in developing countries such as India. The other main concerns in low-resource countries are the lack of an advanced anesthesia gas-scavenging system and modular surgical theatres. As a greenhouse gas that has been present in the atmosphere for more than 100 years and damages the ozone layer, nitrous oxide is three times worse than sevoflurane. Here, we conducted an observational study to quantify the annual nitrous oxide consumption and its environmental impact in terms of carbon dioxide equivalence in one of busiest tertiary health care and research centers in Northern India. Methods: Data related to nitrous oxide expenditure' from the operation theatre and manifold complex of our tertiary care hospital and research center from 2018 to 2021 were collected monthly and analyzed. The outcomes were extracted from our observational study, which was approved by our institutional ethics board (INT/IEC/2017/1372 Dated 25.11.2017) and registered prospectively under the Central Registry (CTRI/2018/07/014745 Dated 05.07.2018). Results: The annual nitrous oxide consumption in our tertiary care hospital was 22,081.00, 22,904.00, 17,456.00, and 18,392.00 m³ (cubic meters) in 2018, 2019, 2020, and 2021, respectively. This indicates that the environmental impact of nitrous oxide (in terms of CO₂ equivalents) from our hospital in 2018, 2019, 2020, and 2021 was 13,016.64, 13,287.82, 10,289.94, and 10,841.24 tons, respectively. Conclusion: This huge amount of nitrous oxide splurge is no longer a matter of laughter, and serious efforts should be made at every central and peripheral health center level to reduce it.

• 통상정보연구
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• 제13권3호
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• pp.433-457
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• 2011

WTO체제가 출범한 이후 회원국 간에 엄격한 다자간 규정의 적용을 보장함으로써, WTO체제에서의 각종 협정의 권위를 강화하고 효율성을 확보하는 수단으로 평가받아오고 있다. 그러나 국제경제 무역의 확대와 더불어 세계는 지구온난화, 멸종위기종, 천연자원의 고갈 등 환경문제를 고민하고 시작했고, 20세기말에 성립된 수많은 다자간 환경협정들에서 알 수 있듯이, 환경문제에 대한 세계적인 관심이 증가하고 있다. 그러나 WTO체제가 자유무역의 부정적인 효과로 인한 환경파괴와 관련하여 동 문제를 해결할 수 있는지에 대한 많은 도전 및 무역과 환경에 관한 논쟁에 있어서 어려운 쟁점이 있다. 첫째, 환경기준의 조화문제, 둘째, 상품의 공정 및 생산방법(PPMs)에 따른 상품표준의 사용문제, 셋째, 환경기준의 무역의무 위반여부를 결정하는데 있어서 사용될 무역규칙(trade rule) 문제, 넷째, 환경관련 분쟁에 있어서 환경관련 협정에 관한 심사기준의 적용문제이다. 따라서 본 연구에서는 무역관련 환경조치를 WTO체제가 어느 정도 어떻게 수용하고 있는가를 구체적으로 밝힘으로써 무역을 통한 성장과 환경보존과 보호가 양립될 수 있는가 그리고 WTO 체제는 환경문제에 공헌하고 있는가에 대한 답을 얻고자 하는데 목적을 두었다.

• 한국대기환경학회지
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• 제32권4호
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• pp.422-434
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• 2016

This study was conducted to understand roles of $NO_x(=NO+NO_2)$ on high $O_3$ episodes at an urban monitoring station in Seoul. Concentrations of NO, $NO_2$, $NO_y$ and $O_3$ were measured intensively at KIST monitoring station which located at urban center in Seoul metropolitan area during May 18~June 13, 2015. Sampling period was planed because high $O_3$ and PM occurred frequently during from late spring to early summer months in Seoul. The experimental site locates in NW from center of Seoul and is surrounded by residential area. Belt highway of the city runs from north to west side nearby experimental site. Vehicle exhaust emissions due to heavy traffic influenced $NO_x$ concentration at the site during northwesterly wind. Specific $NO_2$ concentration was measured by Blue Light photolytic converter, and it was compared to $NO_2$ concentration measured by molybedenum converter. $[NO_2]_{phtolysis}$ was usually lower than $[NO_2]_{molybedenum}$ during the experiment period; however their diurnal variations were very similar. The linear relationship between these $NO_2$ concentrations was found to be $[NO_2]_{phtolysis}$=0.64 $[NO_2]_{molybedenum}$ - 2.6, $r^2$=0.83 during May 16~8, 2015. The difference between $NO_2$ by molybdenum converter and by photolytic converter (${\Delta}NO_2=[NO_2]_{molybedenum}-[NO_2]_{phtolysis}$) accounted for residual $NO_y$ which can represent $NO_z$ (=$NO_y-NO_x$). $O_3$ concentration showed typical daily trend which has maximum at late afternoon and minimum during the night. $O_3$ increased at a rate of 7 ppb/hr since 8 am. and reached the maximum concentration (~80 ppb) at 3 pm.. The diurnal pattern of $O_3$ was inversely related with that of $NO_2$, suggesting that the formation of $O_3$ was the result of photochemical activity of $NO_2$.