• Title/Summary/Keyword: BIG4

Search Result 3,614, Processing Time 0.035 seconds

Comparison of Nitrate and Fluoride Removals between Reverse-Osmosis, Nano-Flitration, Electro-Adsorption, Elecero-Coagulation in Small Water Treatment Plants (소규모 수도시설의 역삼투(RO), 나노여과(NF), 전기흡착(EA), 전기응집(EC) 공정의 질산성 질소 및 불소 이온 제거 성능 비교)

  • Han, Song-Hee;Chang, In-Soung
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.14 no.4
    • /
    • pp.2027-2036
    • /
    • 2013
  • Comparison of removal performance between reverse osmosis(RO), nanofiltration(NF), electrocoagulation(EC) and electroadsorption(EA) for removal of nitrate and fluoride often exceeded the limits of water quality in small water treatment plants. Removals of nitrate and fluoride were 72-92% and 74-85% in RO, 5-15% and 1% in NF, 99% and 44% in EA equipped with MWCNT coated electrodes, 82% and 77% in EA equipped with Cu-MWCNT electrodes, and 11-46% and 69-99% in EC. Consequently, high removals of both ions were anticipated in RO. Effective removal of both ions are possible for EC, but great production of sludge is a big burden. EA equipped with the MWCNT electrodes showed a great fluctuation in removal efficiency, and electrode stability should be upgraded.

The Study on the Physiological Response in Wearing Sportswear in Two Different Environments

  • Kwon, Oh Kyung;Kim, Jin-A
    • Fashion & Textile Research Journal
    • /
    • v.2 no.5
    • /
    • pp.416-422
    • /
    • 2000
  • In this study, to find out the physiological reaction of the human body and the sensation of comfort when people are wearing sportswear which is made of waterproof breathable fabrics under general environmental conditions (temperature : $20{\pm}1^{\circ}C$, humidity : $60{\pm}5%RH$, air current : 0.1 m/sec) and rainy environmental conditions (temperature : $20{\pm}1^{\circ}C$, humidity : $60{\pm}5%RH$, air current : 0.1 m/sec, rainfall : 250 1/hr), we made an experiment with sportswear in an artificial climate chamber and studied the thermal physiological response and subjective sensation. Mean skin temperature of the subjects was low and had a big range of fluctuation in rainy environmental conditions of two condition. Temperature started to increase at the beginning of the exercise, reached the maximum at the 2nd level of the exercise and then started to decline. Rectal temperature showed a slighter increase and bigger range of fluctuation in general conditions than in rainy conditions. Except clothing micro climate in rainy conditions, temperature and humidity and their range of fluctuation around back were higher than those around chest. Humidity was high and had wide range of fluctuation in general conditions. Heart rate was 4.4 beats/min higher in general conditions. In subjective test on rainy conditions, the feeling of discomfort increased due to the raindrops fallen on the skin. Unlike that in general conditions, cold sensation increased and humidity sensation reached to the peak after the exercise. In wearing sportswear made of shape memory breathable waterproof fabric, controlling function over a small amount of heat and water was distinctive while it turned out to be not so comfortable over a large amount of heat and water. Through this, the limitation of shape memory breathable waterproof fabric was recognised.

  • PDF

Pilot Study on Recruiting Medical Checkup Participant by Mail Survey among Korean Vietnam Veterans (베트남 참전군인에서 우편으로 검진대상자를 모집하기 위한 예비조사)

  • Yi, Sang-Wook;Hong, Jae-Seok;Ohrr, Hee-Choul
    • Journal of Preventive Medicine and Public Health
    • /
    • v.36 no.2
    • /
    • pp.171-178
    • /
    • 2003
  • Objective : The aim of this study was to identify the validity of recruiting medical checkup participants of Vietnam veterans using a mail survey, and to identify the 'Vietnam service related characteristics' and 'general characteristics' of Vietnam veterans groups, Method : In this study, a total 900 veterans were randomly selected from the list of Vietnam veterans from f964 to 1973. The veterans were classified into 5 groups, taking into consideration their registered status in the Ministry of Patriots and Veterans Affairs: the VRD (veterans who have agent orange-related diseases), VSD (veterans who have agent orange-suspected disease), VM (veterans who peformed meritorious deeds during the war), VR (veterans who were registered with the Ministry of Patriots and Veterans Affair) and OV (other veterans) groups. By means of postal surveys, the veterans' intention to participate in the medical checkup for our research, and their socioeconomic and general characteristics were investigated. 52 surveys were returned due to the subjects not residing at the listed address, and were excluded from the analysis. Result : 699 of the 848 veterans (82.4%) responded to the survey, of which 619 (88.6%) intended to participate in the medical checkup for our research. The S veterans groups all had similar ages, Vietnam service period, Agent Orange exposure, troop characteristic and wartime class, with the exception of VM, who were older, and with a greater number of officers than the other 4 groups, There was a big difference in the health statius among the Vietnam veterans group. The VM and OV were much healthier than VRD, VSD and VR groups, The socioeconomic stati of the VRD, VSD and VR groups were lower than those of the VM and OV groups. Conclusion : Although there were some limitations, the recruitment, by mail, of medical checkup participants from Vietnam veterans is a valid and feasible method. The VM and OV groups were much healthier, and with higher socioeconomic stati, than the VRD, VSD, and VR groups.

The Impacts of Piezoelectric Elements' Defects On Color & Power Doppler Images (초음파 프로브에서 소자결함이 컬러 및 파워 도플러 영상에 미치는 영향)

  • Lee, Kyung-Sung
    • Journal of radiological science and technology
    • /
    • v.38 no.4
    • /
    • pp.443-449
    • /
    • 2015
  • An ultrasound probe has a big impact on Doppler images even though it has very high risk of frequent function-breakdowns occurring in medical ultrasound scanners. This study experimentally analyses the impacts of an ultrasonic probe's defected elements on power & color Doppler images. The results show that, the bigger the size of defected probe elements is, and the closer a group of action elements is to the center, the more the brightness of images and the velocity of Doppler diminish. When elements' defects increase in color & power Doppler images, false images are formed to be mistaken for blood-vessel plaque in neighboring regions. Accordingly, whenever element defects are suspected, we need check-up process in B-mode. From this respective, it is advisable to have primary interest in a probe and carry out continuous probe QA for ultrasonography.

Changes in postharvest quality of Pleurotus eryngii treated with different shelf temperature and browning inhibitors (큰느타리버섯 유통온도 및 갈변억제처리에 따른 품질 변화)

  • Lee, Yun-Hae;Jeoung, Yun-Kyeoung;Baek, Il-Sun;Lee, Han-Bum;Chi, Jeong-Hyun;Jhune, Chang-Sung
    • Journal of Mushroom
    • /
    • v.11 no.4
    • /
    • pp.297-302
    • /
    • 2013
  • Pleurotus eryngii is one of the main export items in Korean mushroom industry. Whole mushrooms were packed with 30 um polypropylene anti-fog film without trimming. The range of package weight and oxygen permeability of film were 400 g and 2000 $c/m^2$, 24 h,atm, respectively. The anti-browning treatments were sprayed by 0.5%(w/w) solution of Sporix Sporix(Sodium polyphosphate and $ClO_2$ gas The weight loss ratio was increased with increasing shelf period and temperature. There were no big differences in weight loss ratio according to browning inhibitors. In case of $ClO_2$ treatment, the hardness and lightness of stem was showed higher than other treatment for shelf period. As results of freshness, the optimum browning inhibitor of P. eryngii was $ClO_2$ treatment and the shelf life was extended 36days at $10{\sim}15^{\circ}C$.

Effects of cultural characteristics of Lentinula edodes according to LED wavelength with sawdust substrate cultivation (표고 톱밥배지 재배시 LED 광파장이 자실체 생육에 미치는 영향)

  • Baek, Il-Sun;Lee, Yun-Hae;Jang, Myoung-Jun;Jeoung, Yun-Kyeoung;Lee, Han-Bum;Chi, Jeong-Hyun
    • Journal of Mushroom
    • /
    • v.11 no.4
    • /
    • pp.226-229
    • /
    • 2013
  • This study was carried out to elucidate suitable wavelength of light during development of fruit body in Lentinula edodes. The four colors of LED(Light Emitting Diode), blue, green, red and yellow, were irradiated for formation of fruit-body. The effect of color of LED at all growth stage, the lightness of cap showed darker in blue and green LED irradiation than that of red and yellow LED. The longer stipe were resulted in longer wavelength. And the activity of anti-oxidant did not showed big differences according to LED wavelength. We obtained higher commercial yields and lower ratio of abnormal fruit body in green LED than those in control(fluorescent lamp).

Combustion Characteristics and Durability of Diesel Engines Burning BDF 20 (BDF 20을 사용하는 디젤기관들의 연소 및 내구특성)

  • Ryu, Kyung-Hyun;Oh, Young-Taig
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.15 no.3
    • /
    • pp.18-28
    • /
    • 2007
  • Three diesel engines were fueled with BDF 20, a blend of 80% diesel fuel and 20% biodiesel fuel by volume, and run in excess of 200 h to evaluate their combustion characteristics and durability. The engines used for this study were a 4-cylinder 2476-cc displacement IDI diesel engine(Engine 1), a 4-cylinder l732-cc displacement IDI diesel engine(Engine 2), and a single cylinder 673-cc displacement DI diesel engine(Engine 3). Engine dynamometer testing was performed on each engine at regularly scheduled intervals to monitor the performance and exhaust emissions, which were sampled at 1h intervals for analysis, The peak combustion pressure with BDF 20 increased in Engines 1 and 3 over that measured when burning pure diesel fuel, but that in Engine 2 remained constant. Combustion parameters, such as the maximum combustion pressure and corresponding crank angle, did not change over the long-term dynamometer testing. The BSFC with BDF 20 in Engine 1 was less than that measured with pure diesel fuel. The amount of smoke produced with BDF 20 was less for all engines ; the greatest reduction was observed for Engine 3. The NOx emissions were lower in the IDI engines than the DI engine. The traditional trade-off between smoke and NOx emissions was maintained for BDF 20 fuel for Engines 1 and 3. There was not a big difference in the $CO_2\;and\;O_2$ emissions for BDF 20, as compared to pure diesel fuel, but more $CO_2$ was exhausted by Engine 1 than by Engines 2 or 3 and less $O_2$ was exhausted by Engine 1 than by Engines 2 or 3. The engine parts remained clean, except for some carbon attached to the area surrounding the nozzle hole of the DI diesel engine.

An Analysis of Uncertainties in Energy Category: Estimation by using Tier 1 Method (에너지분야 온실가스 인벤토리의 불확도에 관한 연구: Tier 1 에러전파방법을 이용한 추정)

  • Hwang, In Chang;Jin, Sang Hyeon
    • Environmental and Resource Economics Review
    • /
    • v.23 no.2
    • /
    • pp.249-280
    • /
    • 2014
  • IPCC requires the national uncertainties which show how credible the emission of greenhouse gases is. But the Korean government did not submit the total uncertainties, only the detailed uncertainties by items. Also it uses the default values of IPCC including some missing values. This paper tries to estimate the total uncertainties of energy by categories, which accounts for 85.3% in national emission of greenhouse gases. Concretely, it uses Tier 1 method suggested by IPCC. As a result of the analysis, the uncertainties in energy category are 3.4% similar to Finland's. But there was a big difference among greenhouse gases; carbon dioxide 2.7%, methane 116% and nitrous oxide 473%. So this paper suggests Korean government need to improve not only the activity but also the emission factor of data in order to reduce the national uncertainties in energy category.

Comparative Study on the Pigments Applied on the Wall Paintings of Temple in 18~19C (18~19세기 사찰벽화에 사용된 안료 비교 고찰)

  • Son, Young;Kang, Dai Ill;Lee, Hwa Soo;Lee, Han Hyoung
    • Journal of Conservation Science
    • /
    • v.29 no.4
    • /
    • pp.445-450
    • /
    • 2013
  • This study investigated the properties of the painting materials used in the temple wall paintings of the $18^{th}$ to $19^{th}$ centuries by synthetically comparing the component analysis data on the pigments used in the temple wall paintings. The study subjects analyzed from ED-XRF are the data on the 61 temple wall paintings distributed nationwide. The colors of the wall painting coloring layers are classified into seven categories: white, incanadine, yellow, red, green, blue and black color. No big geographical and temporal differences in the type of the pigments were found in the temple paintings of the late Joseon Dynasty distributed in Gyeongsangdo and Jeollado. On the other hand, there were differences in the use of a color when mixing it with other colors depending on the painted parts.

A Study on the Travel Fashion Bag Design Using the Op-Art Textile Patterns -Applying the Artwork of Victor Vasarely- (옵아트(Op-Art) 패턴의 여행용 패션가방 디자인 연구 -빅토르 바자렐리(Victor Vasarely)의 작품 응용을 중심으로-)

  • Kim, Min-Hye;Park, Hye-Won
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.35 no.3
    • /
    • pp.371-384
    • /
    • 2011
  • This study with 'trip' as a theme, aims to develop textile designs and fashion bags for travel which is widely applicable fitting traveler's T P O, applying Victor Vasarely's artwork. During the planning process of design, 'Whenever & Wherever's concept was set by analyzing fashion trend information in 2010-11 F/W proposed by Interfashion Planning and FCK; in addition, 'Bobos' were selected as research targets. It organized 4 images of 'Modern', 'Romantic', 'Classic' and 'Fantastic'. The motives are proposed textile design with '$Cross^2$', 'Falling Z', 'Cir-Classicism' and 'Skinny-holic' per each theme. The designs developed were printed out and into polyester canvas with a Polaris V6 DTP from dgen, Corp. Textile designs developed were applied for 'two-way' formed fashion bags for traveling with high practicality. Fashion bags for traveling consisted of big bags, tote bags, and hip sacks; a total of 12 works (4 sets per theme) were produced. This study sought practical plans for artworks by producing fashion goods through a DTP system. The results of this study can be used as guidelines for further studies and as a significant contribution to the creation of high values for exciting fashion products.