The objective of this study was to investigate the response characteristics and performance of a biofilter in the removal of ammonia, as a malodor compound. A trickle-bed type biofilter was applied for this study, and operated at the ammonia loading rate of 0.97-15.52 g/m3·h. The results of the experiment indicate that the critical loading rate of ammonia to the biofilter was 10.7 g/m3·h and the elimination capacity was 11.6 g/m3·h. The analysis of nitrogen mass balance in the reactor indicates that inlet nitrogen as gas phase was converted through the biofilter into NH4 + (41.5% by mass), NO2 - (43%), and NO3 - (15%) as the available form of nitrogen in the effluent liquid. Free ammonia concentration in the effluent liquid was estimated as being in the range from 0.14 to 2.93 mg/L (average 1.7 mg/L) during the experimental period.

This study was performed as the preliminary research to calculate the concentration of radon exposure and the annual effective dose in public hot spring bath-house. The research found that public bathhouses are the primary cause of the indoor air radon concentration inside a hot spring bathhouse. The indoor radon concentration inside a bathhouse differs significantly by region and among bathhouses in the same region, indicating that the indoor air radon concentration is affected by many factors. The annual effective indoor radon dose by exposure is estimated to range from 1.2×10−2mSv/y to 2.5×10−2mSv/y. Since this research is considered as preliminary research, further and additional relevant research to more reliably calculate the result are necessary, including accumulative research for indoor radon concentrations, and research for exposure coefficients such as the behavior patterns of public bathhouse users, etc.

The correlation analysis between odor sensor and air dilution olfactometry method with odor emission facilities was performed for the real-time evaluation of odor emitted from the 13 facilities. The total correlation was less significant for all facilities due to various emission characteristics of odor. The correlation for the individual facility, however, showed a higher correlation coefficient (R=0.7371~0.9897). Especially, the strong correlation (above 0.9) was observed for the industry type with the odor characteristics like tobacco, styrofoam, acetic acid, and burning smell. The repeated odor measurements using the odor sensor showed good reproducibility with the mean relative standard deviation of 5.06%. The odor sensor could be useful tools for identifying and evaluating odor with an olfactometry in field, if the use and proofreading of the odor sensor are improved by a standardized method.

The principal hygienic problem caused by livestock industry is the odor exposed to farm workers. This study was performed to assess air cleaner efficiency for reducing odor through on-site evaluation. The concentration of ammonia and hydrogen sulfide, which are major odorous compounds generated from livestock building, were monitored by realtime direct recorder. The odor mixture was measured by air dilution method applying human noses of five panels. Their reduction efficiencies were represented by difference between initial concentration exhausted by non-treatment and concentration measured after treatment of respective control mechanism (water, germicide and plasma ion) of air cleaner. Mean levels of ammonia and hydrogen sulfide were 1.84 (SD:0.22) ppm and 76.83 (SD:1.37) ppb for non-treatment, 1.23 (SD:0.09) ppm and 59.07 (SD:2.68) ppb for wet scrubber (water), 1.08 (SD:0.03) ppm and 58.55 (SD:1.62) ppb for wet scrubber (germicide), and 0.96 (SD:0.03) ppm and 53.66 (SD:1.37) ppb for plasma ion, respectively. Mean dilution factors of odor mixture were 100 for non-treatment, 66.9 for wet scrubber (water), 144.2 for wet scrubber (germicide), and 66.94 for plasma ion, respectively. Based on the results obtained from on-site evaluation, ammonia and hydrogen sulfide showed the mean reduction efficiency of 40% and 25.7% compared with non-treatment process of air cleaner, respectively. In the case of odor mixture, the highest dilution factor was observed at wet scrubber (germicide) compared with other control mechanism of air cleaner.

The purpose of this study is to evaluate the performance of a tube and badge type NO2 passive air sampler. The principle of the method is a colorimetric reaction of NO2 with N-1-naphthylethylendiamine under acidic conditions. The sampling rates for the tube and badge type passive air samplers was determined 12.3 ± 4.4 mL/min and 27.3 ± 4.9 mL/min, respectively, as obtained from the slope of the linear correlation between the NO2 mass collected by the passive air sampler and the NO2 concentration with the NO2 analyzer. The tube and badge type passive air sampler were moderately correlated with a correlation coefficient of 0.9112. The measurement for the precision and accuracy of the passive air sampling was carried out with duplicate measurement of passive air samplers. The passive air sampler had good precision and accuracy for measuring NO2 in atmosphere. A good correlation was observed between the passive air sampler and the NO2 analyzer with a coefficient of determination of 0.9153 (tube type) and 0.9514 (badge type). This passive air sampler would be suitable for the NO2 concentration monitoring in atmosphere.

PURPOSES : The use of roller-compacted concrete pavement (RCCP) is an environmentally friendly method of construction that utilizes the aggregate interlock effect by means of a hydration reaction and roller compacting, demonstrating a superb structural performance with a relatively small unit water content and unit cement content. However, even if an excellent structural performance was secured through a previous study, the verification research on the environmental load and long-term durability was conducted under unsatisfactory conditions. In order to secure longterm durability, the construction of an appropriate internal air-void structure is required. In this study, a method of improving the long-term durability of RCCP will be suggested by analyzing the internal air-void structure and relevant durability of roller-compacted concrete. METHODS: The method of improving the long-term durability involves measurements of the air content, air voids, and air-spacing factor in RCCP that experiences a change in terms of the kind of air-entraining agent and chemical admixture proportions. This test should be conducted on the basis of test criteria such as ASTM C 457, 672, and KS F 2456. RESULTS : Freezing, thawing, and scaling resistance tests of roller compacted concrete without a chemical admixture showed that it was weak. However, as a result of conducting air entraining (AE) with an AE agent, a large amount of air was distributed with a range of 2~3%, and an air void spacing factor ranging from 200 to 300 ㎛ (close to 250 ㎛) coming from PCA was secured. Accordingly, the freezing and thawing resistance was improved, with a relative dynamic elastic modulus of more than 80%, and the scaling resistance was improved under the appropriate AE agent content rate. CONCLUSIONS: The long-term durability of RCCP has a direct relationship with the air-void spacing factor, and it can be secured only by ensuring the air void spacing factor through air entraining with the inclusion of an AE agent.

The main object of this study is to investigate the collection characteristics of an electro-static multi-staged impaction system, experimentally. The experiment is carried out to analyze the characteristics of pressure drop and collection efficiency for the present system with the experimental parameters such as the inlet velocity, stage number, applied voltage and shape of discharge electrode, etc. In results, the pressure drop is shown below 148 mmH2O lower than that of the conventional bag filter at inlet velocity 3.46 m/s and 5 stage. For 5 stage , the collection efficiencies are to be 97.4, 99.0% with the applied voltage 0 kV at the inlet velocity 2.07, 3.46 m/s, while 98.4, 99.9% with 40 kV of a sharp edge discharge electrode. Additionally, the present system is to be considered as an effective compact system for a removal of particulate pollutants from marine diesel engines due to much higher collection efficiency and appropriate pressure drop.

좋은 품질의 묘를 이용하는 것은 성공적인 작물 재배 및 생산을 위해 필수적이다. 그러나 구입묘 이용시에는 육묘장에서 재배농가로 운송하는 과정에서 묘의 품질이 저하될 우려가 있다. 본 연구는 토마토묘의 운송시 온도 조건이 정식 후 생육 및 수량에 미치는 영향을 검토하기 위해 수행되었다. 본엽이 9-10매 정도 전개하고 1화 방의 1번화가 피기 직전 또는 핀 토마토 접목묘를 이용 하여, 온도 조건을 각각 10, 25, 40oC, 처리시간을 2, 4, 6시간으로 조합 처리하였다. 처리 종료 후 10oC 처리구에 비해 25, 40oC 처리구에서 더 낮은 NDVI 값을 나타 냈으며, 40oC 처리구의 지하부 생체중이 가장 낮았다. 40oC 처리구 토마토묘는 정식 5-7일 후 아래잎에서 황화 및 잎마름 증상이 발생하였다. 1화방 착화절위는 처 리간에 차이가 없었으나, 착과수는 40oC/6시간 처리구에서 감소하여 착과수가 2개였다. 40oC/6시간 처리구의 경우 1화방 수량도 감소하여 대조구의 40% 정도였다. 따라서 묘의 운송시에는 온도조건이 지나친 고온 또는 저온이 되지 않도록, 단순 상온유통이 아닌 온도조절 장치 구비를 통한 온도조절이 요구된다. 6시간 이내의 단거리 운송의 경우 10-25oC 범위로 온도를 관리해줌으로써, 정식 후 장애 발생 없이 안정적인 착과 및 수량확보가 가능할 것으로 판단된다.

During periods where a fine dust watch was announced, we measured particulate matter by the light scattering method and the gravimetric method in accordance with the application of an air cleaner in 3 homes. The first investigation showed a lower indoor particulate matter 2.5 (PM2.5) concentration distribution than normal when there was a fine dust warning. Also, it was found that the result of the second research was similar to the first research, and was the effect of an air cleaner. The result of a comparison of black carbon (BC) concentration in accordance with an air cleaner at one room showed a lower concentration distribution than normal, as in the first and the second research when there was a fine dust warning. PM2.5 risk reduction effect showed 9.09E-5 (light scattering method) ~ 9.37E-5 (Gravimetric method) and 1.71E-4 (Light scattering method) ~ 1.76E-4 (Gravimetric method). Therefore, it was found that when there was a fine dust watch without ventilation, if air cleaner with the proper capacity is used and the influx of outside air reduced, the harmful effects of the fine dust can be lessened.

Environmental tobacco smoke (ETS) contains a large variety of substances, of which at least 50 are known to or are believed to be carcinogenic. Although the Ministry of Health and Welfare has started to prevent public exposure to ETS by enacting indoor smoking bans, some facilities still allow their customers or users to smoke indoors. In this study, indoor air quality in a pub was investigated by monitoring particulate matters (PM1.0 and PM2.5), heavy metals (As, Cd, Cr, Pb) and nicotine concentration to figure out the influence force of smoking behavior on indoor air quality. Smoking behaviors are revealed to be a major contributor the contamination of indoor air in pubs. The range of PM2.5 mass concentrations were 82.2~208.0 μg/m3 and the mean concentration of PM2.5 was 135.9 μg/m3. In the case of nicotine, the mean concentration was 12.2 μg/m3 with a range from 2.7 to 24.1 μg/m3. In the results of metal analysis, the levels of heavy metals in particulate matters in a pub were found to be much higher than those of the other public facilities.

국가의 외환위기 이후 경기침체에 따른 건설산업의 경기회복을 위하여 정부는 그 산업의 시장진입에 대한 장벽을 제거하는 등 규제를 완화하고, 발주체계의 개편 등을 통하여 전반 적인 개선을 도모하고 있으나, 겅기침체로 인한 정부, 지방자치단체, 대기업 등의 투자저하 는 결국, 건설업을 영위하는 기업들의 경영난으로 이어지는 원인이 되고 있다. 그 가운데 하나가 정부에서 발주하는 공공공사에 대한 공기연장에 따른 간접비의 증가분을 인정하지 아니한다는 것이다. 이를 요약하면 정부가 건설산업에 대한 규제완화로 인하여 시장의 진 입장벽을 낮추고 이에 대한 일환으로 건설업면허의 취득요건을 면허제에서 등록제로 전환 시킴에 따라 건설업을 영위하고자 하는 일반기업들이 증가한 반면에, 발주자의 귀책사유 즉 예산부족 등으로 인한 공기연장에 따른 간접비 인정은 미미하여 건설업을 영위하는 기 업들의 경영난은 더욱 심각하게 되는 등 문제가 되고 있다. 공사기간의 연장에 따른 간접비와 관련하여, 공사계약에서 체결된 공사대금이나 준공기한 등 확정된 계약내용은 원칙적으로 변경할 수 없으나 정부의 예산부족, 민원, 용지보상의 지 연 등 발주자의 귀책사유로 인하여 공사착공이 지연되거나 중단되는 경우 국가를 당사자로 하는 계약에 관한 법률에 의하여 발주기관은 공사기간의 연장에 따른 추가 비용을 실비로 정산하여 계약금액을 조정하도록 법률로써 규정하고 있으나 종래 발주자는 오랜기간 다양 한 근거를 이유로 그 연장에 따른 간접비의 증가를 인정하지 아니하여 문제가 되고 있다. 이에 따라 기획재정부는 총사업비관리지침 등의 개정을 통한 공사기간의 연장에 따른 간접 비 증가를 최근 인정함으로써 민간기업으로 부터 지속적인 소송이 제기되고 있다. 그러나 공사기간의 연장에 따른 간접비의 증가는 총사업비관리지침에 의하여 실비 등으로 조정할수 있으나, 그 범위 대상, 범위, 지급기준 등이 문언에 명시되어 있지 아니하여 또한 문제가 되고 있다. 따라서 발주자와 수급인의 계약당사자는 소송 또는 건설분쟁조정위원회의 조정 을 통하여 이를 해결할 수밖에 없고 조정의 대상이 되는 실제투입비용은 수급인의 입장에 서 그 기준을 명확하게 판단하기가 어려워 그 비용을 모두 청구할 수밖에 없는 것이다. 설 계변경으로 공사금액이 감소하면서 공사기간이 연장될 경우 간접비를 지급 하여야 하는 문 제점과 설계변경으로 공사금액 증가와 공사기간의 연장으로 간접비를 이중으로 지급하여 야 하는 문제점이 있어 소송과 건설분쟁조정위원회에서도 이를 명확하게 구분하지 않고 있 어 다음과 같이 개선방안을 제시하였다. 공사기간이 경과되어 설계변경으로 인해 공사금액 이 감소할 경우에 실비로 간접비를 지급하여야 하며, 공사금액이 증가할 경우 간접비가 증 가한다 하여도 미미할 경우가 있으므로 물량증가에 따른 간접비는 제외하고 공기연장에 따 른 실비를 지급하여야 한다. 실비의 범위는 실증적으로 분석한 결과에도 공기연장에 따른 간접비 지급범위에 대하여 전 체 조사 응답자의 30.80% 이상은 현장의 인건비와 경비, 30.10% 이상은 현장과 본사의 일 반관리비, 32.18% 이상은 현장과 본사의 일반관리비와 이윤을 지급하여야 한다는 비슷한 비율로 나타나 현장과 본사의 일반관리비를 간접비를 실비의 지급범위로 개정･보완하여야 한다. 그러므로 계약당사자는 공사계약을 체결하는 과정에서 사전에 계약금액의 조정에 대한 약 정을 체결하거나 법률기준을 상호 약정하여 문제발생의 소지를 방지할 필요성이 제기되고 있으며, 향후 이와 같은 문제발생이 점차 증가할 것으로 예상되므로 이에 대한 사전준비의 노력이 더욱 더 이루어져야 할 것으로 판단된다.

The surface rheological properties of polymer monolayer show complicated non-linear viscoelastic flow phenomena when they are subjected to spreading flow. These spreading flow properties are controlled by the characteristics of flow units. The kinetics of the formation of an interfacial film obtained after spreading poly(diisobutylene maleic acid) at air-water interface were studied by measuring of the surface pressure with time. The experimental data were analyzed theoretically according to a nonlinear surface viscoelastic model. The values of dynamic modulus, static modulus, surface viscosities and rheological parameters in various area/ monomer were obtained by appling experimental data to the equation of nonlinear surface viscoelastic model.

In this study, by comparing the heating performance when operating the air conditioning system that is installed directly air-cooled(heater) air conditioning central air conditioning system of the ship, with improved performance, through the actual measurement study of thermal environment of the cabin, Ship's air conditioning in the future it is intended to be used as a basic data experience of design and planning.

The spatial resolution of 3-Dimensional numerical model has a very important influence on the model result. The land-use and orographic effect is also influenced by the spatial resolution of the model. A large errors in model performance are produced depending on the terrain complexity. In this study we performed Air Quality Forecast model (AQF) simulation and analyzed the change in the ozone concentration depending on spatial resolution at small and medium-sized mixed areas with urban and rural area types. As the result, improving the spatial resolution improved the simulation of the downward trend of ozone at night. This was mainly due to improvement of local concentration contaminants at fragmented grid. In the case of wind speed, the model with high-resolution shows better agreement with observation at night.

지구온난화에 대한 현사시나무의 적응반응을 구명하기 위해서, CO2농도 및 기온 상승된 조건에서 80 일간 생장한 현사시나무 삽목묘의 수분생리특성을 조사하였다. 대조구는 기온이 주간 22℃, 야간 17℃ 이고, CO2농도는 주간 380ppm, 야간 400ppm이다. CO2농도 및 기온을 상승시킨 처리구는 기온이 주 간 27℃, 야간 22℃이고, CO2농도는 주간 770ppm, 야간 790ppm이다. 처리구는 잎이 전개된 개수, 개 엽의 평균면적, 전체 엽면적이 대조구에 비해서 낮은 값을 나타냈다. 그리고 처리구는 대조구에 비하여 지상부의 건중량이 적고, 지하부의 건중량이 많았으며, 지하부에 대한 바이오매스의 분배율이 높았다. 이러한 결과로 CO2농도 및 기온이 상승되면 수분을 필요로 하는 동화기관의 면적이 감소되고, 수분을 흡수하는 지하부에 대한 바이오매스 분배율이 높아짐을 확인할 수 있었다. 또한 처리구는 광도 및 CO2 농도의 변화에 상관없이 기공전도도와 증산속도가 대조구에 비하여 낮게 유지되고 광합성에 대한 수분 이용효율이 대조구보다 높게 나타냈다. 이 결과를 통하여 동화기관의 수분손실 억제반응과 수분이용효 율이 증대반응을 확인할 수 있었다. 그리고 처리구는 절단한 잎이 건조공기에 노출되어도 상대함수율이 대조구에 비하여 천천히 감소하는 경향을 나타내 동화기관의 수분손실 억제반응이 재확인되었다.

This paper reviewed the effect of job burnout on safety outcomes, and the moderating effect of safety climate in Korean Air Force. The prevalence of burnout in air force pilots has not been determined and reviewed. It is also unknown whether pilots’ burnout may affect their safety outcomes(safety action & compliance). The primary objective of this study was to determine the prevalence of burnout and it’s effect on safety outcomes. For cross-sectional survey, 910 questionnaires were sent to pilots in air force, and 722 questionnaires among them were returned effectively. The questionnaire was divided into 4 parts examining pilots’ demographic factors, job burnout, safety outcomes, and safety climates. To test and review proposed hypotheses, hierarchical multiple regression analysis was used. The results of statistical analysis appeared as follow; 1) EE(emotional exhaustion) and RPA(reduced personal accomplishment) effected negatively on safety action. 2) EE and RPA effected negatively on safety compliance. 3) EE effected more positively on safety action in higher SS(superior support) group than in lower SS group. 4) RPA effected more positively on safety compliance in higher SS(superior support) group than in lower SS group. 5) RPA effected more positively on safety action in higher CW(coworker support) group than in lower CW group.

In this study, to develop high-efficiency environmental improvement system that can be combined with hot and cold potable water supply to poultry air conditioning for the summer increase heat stress relief and winter feed efficiency through optimal design hwihan The aim of this study was to provide basic data. As a cage the size of the system installed is 100m2 test capacity 20RT district heating and cooling of air-to-water heat pump and the control was composed of electric hot water boilers. First of cage sizes for heating load design, materials, heat pump capacity, air capacity, storage tank, drinking water tank capacity, etc. were determined. The capacity of the heat pump was set to 20RT cage captive birds are erected as vertically and horizontally × height × (13 × 21 × 4.5m). Storage tank 3 tons and capacity of 10 tons potable water tank was designed. In the future, the size of the cage, designed according to the best breeding two numbers are needed.