• Title/Summary/Keyword: Ventilation effect

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Analysis of Aerosol Optical Properties in Seoul Using Skyradiometer Observation (스카이라디오미터 관측을 통한 서울 상공 에어러솔의 광학적 특성 분석)

  • Koo, Ja-Ho;Kim, Jhoon;Kim, Mi-Jin;Cho, Hi Ku;Aoki, Kazuma;Yamano, Maki
    • Atmosphere
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    • v.17 no.4
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    • pp.407-420
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    • 2007
  • Optical characteristics of aerosols in Seoul are investigated from the measurements of sky radiance by Skyradiometer at Yonsei University from December 2005 to November 2006. Aerosol optical depth (AOD) shows a maximum in June due to weak ventilation and particle growth by aging process and hygroscopic effect. Single scattering albedo (SSA) and Angstrom Exponent (AE) show the lowest value in spring due to the Asian dust. It is clear that coarse mode is dominant in spring and fine mode is dominant in summer from the volume size distribution measured in this study. The explanations on the changes of aerosol loadings are provided through the correlation between AOD and AE, while the pattern of wavelength dependency related to particle size is shown through the correlation between SSA and AE. Backward trajectory analysis by HYSPLIT provides information about origin of aerosol, which allows us to classify the case according to the source region and the path distance. Although the direction of backward trajectory traces back mostly to west, coarse mode particle is dominant in the case of long pathway and fine mode particle is dominant in the case of short pathway. This discrepancy is caused by the regional difference of emitted particles.

The Influence of Wearing Army Combat Uniform on the Thermal Responses in Heat Environment (서열환경하에서의 전투복착용이 체온조절에 미치는 영향)

  • Kim, Tae Gyou;Cho, Ho Hyun
    • Fashion & Textile Research Journal
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    • v.16 no.1
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    • pp.167-174
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    • 2014
  • The physical properties of textile materials and thermal physiological responses of the human subjects were evaluated with 4 different types of the army combat uniforms including US, German, Korean and general uniforms for this study. 8 male adults were used as the human subjects and the tests were done in the environmental chamber that was $25{\pm}0.1^{\circ}C$ of temperature, $65{\pm}5%$ of relative humidity and below 0.3 m/sec of air velocity. The test protocol consisted the rest period for 20 min., the exercise period for 20 min., the rest period for 20 min., the exercise period under wind condition for 20 min., and the recovery period for 20 min. The human subjects walked with 4.5 km/hr for 10 min., ran 7.5 km/hr for 10 min. during the first exercise period and walked and ran with the same speeds under 3.5 m/sec of the air velocity that simulated outdoor condition during the second exercise period. The test results of the study were as follows; The wind condition affected the skin and microclimate temperature of the human subjects lower compared to without wind condition, but had insignificant effect on the humidity control. The low air permeability of Korean uniform caused blocking the elimination of the humidity from the body and the regulation of body temperature. However, Korean uniforms could be the excellent one with the designs considering the ventilation of the uniforms and the textile fabrics with better air permeability.

Thermo-physiological Responses by Presence of Vents and Difference in Clothing Length for Construction Site Working Clothes (통기구 유무와 옷 길이 차이에 따른 건설현장 작업복의 온열생리반응)

  • Kim, Seong-Suk;Kim, Hee-Eun
    • Fashion & Textile Research Journal
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    • v.20 no.2
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    • pp.202-209
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    • 2018
  • This study examined thermo-physiological responses according to the design change of construction site working clothes (control (C) working clothes; prototype (P) working clothes). We measured rectal temperature, skin temperature, micro-climate within the clothes and sweat rate. In the evaluation of physiological functionality, based on pattern improvement in working clothes, P working clothes showed significantly lower rectal temperatures, trunk and thigh skin temperatures than C working clothes. It is preferable that rectal temperature should be kept low during work that is not favorable to an increase in body temperature. P working clothes were more physiologically functional than C working clothes. In addition, P working clothes showed significantly lower temperatures in the trunk and thigh parts in a micro climate temperature. We could explain that the side seam zipper on the pants and the gusset on armpit parts create an air permeability effect of lowering the temperature of micro-climate. Aggressive ventilation through the slit of the garment is an important factor for the restoration of the physiological function of the worker at rest between work. Sweat rate showed a higher level in C working clothes than P working clothes. When working in a hot environment, workwear needs to be designed so that the worker is not exposed to thermal stress. Therefore, it was evaluated that the P work clothes used in this study alleviated the physiological burdens of heat.

A Study on the Direction of Development in Industrial Health Officer Education (산업보건(産業保健) 직무교육(職務敎育) 개선방안(改善方案)에 관(關)한 연구(硏究))

  • Whang, Byoung Moon;Ham, Wan Shik;Park, Dong Gi
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.1 no.1
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    • pp.29-46
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    • 1991
  • The study was conducted with 611 Industrial Health officer for 2 years(1998 : 394person, 1989 : 217 person). The purpose of this study was to measure efficiency of the Industrial Health Officer course (use of questionaire) also, in the furure, we would like to make a standard on the management of Industrial Health Officer (software & Hardware) The result are as follows: 1. the response of satisfaction was revealed highly 51 % on the Curriculum. 2. The response of high qualities was revealed highly 92% in the content of textbook. 3. The response of practical program was revaled highly 67.7% in composition of curriculum. 4. The response of high-class instructor was revealed highly on the selection of instructor. 5. the response of a proper term was revealed almost trainees on the education term. 6. When industrial hygienist conducted their Health task, difficulty point, first, the lack of top manager on the health-management in industries, second, take a hold coccurently with another task third, not secure theirs status in industries. 7. almost of Industial Health Officer want to taken highly practical education program, a field of industrial ventilation, measurment of working enviroment. 8. They wanted to taken a practical program that they could conduct handling they-self measuring device, in order to enhance the effect of hygiene education. 9. They responsed size of ideal class that the number of Industrial Health Officer was less than 20 person.

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Prevention of Barn Rot during Curing of Burley Tobacco. II. Effect of Curing Conditions and Supplemental Heat. (버어리종 잎담배 건조시 부패방지 II. 건조조건과 보조화력의 영향)

  • 배성국;임해건;한철수
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.4
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    • pp.331-334
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    • 1989
  • This studies were carried out to investigate the effects of the management of curing barn and the use of supplemental heat on prevention of barn rot during the rainy season. The managemental methods of curing barn were combined with hanging spaces ranged from 15cm to 30cm and ventilating conditions. The supplemental heat was applied with oil burner and oil fan heater. Barn rot was reduced in the wider hanging spaces, and the effects of hanging spaces was larger with ventilating during curing. Barn rot decreased by ventilating condition than non-ventilation. The use of supplemental heat dropped to lower relative humidity in curing barn. Supplemental heat and forced-air movement greatly reduced barn rot in comparison with tobacco cured under natural conditions.

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Dust Concentration Monitoring in Korean Native Cattle Farm according to Sampling Location and TMR Process (한우사 내부 위치 및 TMR 배합 작업에 따른 분진 모니터링)

  • Park, Gwanyong;Kwon, Kyeong-Seok;Lee, In-bok;Yeo, Uk-Hyeon;Lee, Sang-Yeon;Kim, Jun-Gyu
    • Journal of The Korean Society of Agricultural Engineers
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    • v.59 no.4
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    • pp.75-83
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    • 2017
  • Many parts of problems in livestock industry today are associated with organic dust. Endotoxin and toxic gasses on the surface of dust and dust itself can cause aesthetic displeasure and respiratory disease. It also reduces livestock productivity by suppressing immunity of animals and carrying microbes causing animal disease. However, dust level of cattle farm was rarely reported in Korea, and regulation for cattle farm worker does not exist. In this paper, dust concentration and environmental condition were regularly monitored in a commercial Korean native cattle farm. The measurement was conducted according to location and working activities. From the measurement, distribution of dust concentration was affected by wind environment, as the result of natural ventilation. TMR mixer was a major source of dust in target cattle house. The maximum inhalable dust concentration was 637.8 times higher than exposure limit as feed dropped into the TMR mixer. It was expected that dust generation could be affected by particle size and drop height of feed. This study suggests potential risk of dust in cattle farm, and necessity for latter study. Effect of aerodynamic condition and TMR processing should be investigated for dust reduction study.

The Effect of applying Subsidiary step developed for CPR on the main stretcher during movement (이동 중 주들것에서 심폐소생술을 위해 개발된 보조발판(C-step)의 적용 효과)

  • Shim, Gyu-Sik
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.12
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    • pp.5950-5957
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    • 2012
  • CPR with minimized hands-off time is one of integral factors for the improvement of the survival rate of patients. The purpose of this study was to examine the relationship of the installation of C-steps on the main stretcher to CPR accuracy and errors. The subjects in this study were 70 paramedics in 10 firehouses in the province of C(35 for control group, 35 for experimental group), and their CPR accuracy on the main stretchers was checked. As a result, it's found that the main stretchers equipped with the C-steps served to boost the accuracy of chest compression by creating suitable environments for that in terms of height and posture(t=65.104, p=.000), to improve the accuracy of artificial respiration by providing a proper amount of ventilation(t=5.207, p=.000), and to bolster the self-confidence of the paramedics about CPR(t=-10.612, p=.000). In conclusion, the mounting of C-steps on the main stretcher is expected to be of use for the improvement of the survival rate of cardiac-arrest patients by ensuring the precise performance of high-quality CPR.

The Comparison of Effects the Pulmonary Function to Breathing Exercise in Water and on Land (수중호흡운동과 지상호흡운동이 폐 기능에 미치는 효과 비교)

  • Kim, Sun-Young;Kim, Chan-Mun
    • Journal of Korean Physical Therapy Science
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    • v.8 no.1
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    • pp.885-892
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    • 2001
  • The purpose at this study was comparied at effect the pulmonary function to breathing exercise(BE) in water with on land. The result was as follow: FVC(Forced Vital Capacity) was decreased 1.5% in control group, increased 1.5% in BE on land group and increased 6.5% in water group after BE, but no significant difference in water group. FEV1(forced expiratory volume at one second) was increased 0.2% in the control group, decreased 0.7% in BE on land group and increased 5.7% in BE in water group after BE, but no significant difference in water group. MVV(maximal voluntary ventilation) was significant difference in BE in water group who was increased 12.2% after BE. It was decreased 1.0% in the control group and increased 0.2% in BE on land group. VC(vital capacity) was decreased 1.5% in the control group, increased 6.2% in BE on land group and increased in BE in water group after BE, but no significant difference in water group. IC(Inspiratory Capacity) was decreased 0.5% in the control group, increased 7.5% in BE on land group and decreased 2.0% in BE in water group after BE, but no significant difference on land group. ERV(Expiratory Reserve Volume) was decreased 0.5% in the control group, increased 3.0% in BE on land group and increased 8.5% in BE in water group after BE, but no significant difference in water group.

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An Experimental Study on the Critical Velocity Considering the Slope in Tunnel Fire (경사터널내 화재 발생시 경사도가 임계속도에 미치는 영향에 관한 연구)

  • Kim, Seung-Ryoul;Jang, Yong-Jun;Ryou, Hong-Sun
    • Journal of the Korean Society for Railway
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    • v.11 no.1
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    • pp.7-12
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    • 2008
  • An experimental study has been conducted to investigate the effect of tunnel slope on critical velocity by using the model funnel of the 1/20 reduced-scale applying the Floods scaling law. the square liquid pool burners were used for methanol, acetone and n-heptane fires. tunnel. Tunnel slopes varied as five different degrees $0^{\circ}$, $2^{\circ}$, $4^{\circ}$, $6^{\circ}$ and $8^{\circ}$. The mass loss rate and the temperatures are measured by a load celt and K-type thermocouples for tunnel slope. Present study results in bigger the critical velocity than the research of Atikinson and Wu using the propane burner. Therefore, when estimating the critical velocity in slope tunnel, the variations of the heat release rate is an important factor. The reason is the ventilation velocity directly affects variation of heat release rate when slope tunnel fire occurred.

A Prediction Model for TVOC and HCHO Emission of Paint Materials (페인트에서 방출되는 TVOC 및 HCHO 방출량 예측모델)

  • Kim, Hyung-Soo;Lee, Kyung-Hoi
    • KIEAE Journal
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    • v.3 no.1
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    • pp.13-20
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    • 2003
  • It is highly recognized that there is need for protection against indoor air pollution, as we realize environmental pollution is growing, For example, in an indoor environment, a person spends more than 80 percent of their time inside the building. Thus, concern about indoor decoration materials is growing, since they cause pollution in the rooms of an apartment, as well as in offices. As the indoor decoration materials become more diverse and lusurious, so the effect of VOCs(Volatile Organic Compounds) and HCHO(Formaldehy) is growing. The indoor decoration materials cause the Sick Building Syndrome, such as headaches, dizziness, or lack of concentraion, and they in turn cause serious deterioration in people's health. In this study, I probed the status of the indoor air pollution and carried on an investigation and analysis about the prevention technique. In doing so, I performed experimental tests and an assessment of the indoor decoration materials of an apartment. I also examined elements of the emitted and the emission. Finally, I examined the character of emissions, by changing environmental conditions, such as the temperature, humidity, and ventilation. With respect to VOCs tests, I applied the method of solid state adsorption using the adsorptive tube, based on the measurement of the American EPA TO-17, ASTM 5116-97, and the measurement of the Japanese Wall Decoration Industrial Association. The tested sample was analyzed by High Performance Liquid Chromatography, after going through the process of dissolvent extraction. As subjects of the test, Paint were selected. The process of this test is as follows; first, I figured out the character of the emission, by measuring the emitted concentration of VOCs and HOHC from the indoor decoration materials of an apartment. Second, I made a small-scale chamber and the test was processed in the chamber in order to suggest an environment-friendly prediction modlel development.