• 제목/요약/키워드: Black-Ice

검색결과 54건 처리시간 0.021초

폐CNT를 혼입한 시멘트 복합체의 강도 및 열전달 특성에 대한 기초적 연구 (Fundamental Study on the Strength and Heat Transferring Charcteristic of Cement Composite with Waste CNT)

  • 구현철;김운학;오홍섭
    • 한국건설순환자원학회논문집
    • /
    • 제10권1호
    • /
    • pp.66-73
    • /
    • 2022
  • 동절기 콘크리트 포장체의 블랙아이스 발생위험을 낮추고 동결에 의한손상을 방지할 목적으로 콘크리트의 전도저항성을 활용하여 자기 히팅 콘크리트를 개발하고자 하였다. 이를 위하여 분말형과 액상형 폐CNT와 전도촉진을 위해 폐음극재를 사용하여 강도변화와 온도 발열특성을 평가하고자 하였다. 액상형 폐CNT가 모르타르내에서 분산정도가 효과적이고, 강도저하가 작게 발생하는 것으로 분석되었다. 또한 모르타르에 스틸매쉬, 구리포일과 구리선을 전극으로 적용하여 DC 24 V를 공급하였으며, 폐CNT, 폐음극재과 탄소섬유 혼입율에 따른 온도변화 특성을 평가하였다. 또한 선정된 최적배합으로부터 전극간격에 따른 온도 특성을 평가하여 AC 50 V 까지는 전극간격 100 mm 까지는 충분한 발열 특성을 갖는 것을 확인하였다.

6·4이후 중국 영화에 표출된 냉소주의 양상고찰

  • 박완호
    • 중국학논총
    • /
    • 제58호
    • /
    • pp.91-119
    • /
    • 2018
  • As for the various pathological phenomena of the society which is getting worse without any improvement, the film paints the phenomenon nakedly with the cold and cynical gaze on the basis of realism. These attempts originated in the Chinese art world, and they cynically sketched a Chinese society that lost hope after 6·4. The cynicism of the art world contains meanings such as instruction, meanness, passion, indifference, and mockery. In particular, the distrust of the social system after 6·4 and the collapse of the Soviet and Eastern European socialist nations gave the Chinese people a skeptical view of socialism. This situation of the times has a cynical viewpoint to face as it is instead of prudent criticism. This cynical view was embraced by filmmakers who were not silent on The pathological phenomenon of society, and they were directed to films. is a film about the love, separation, suicide, frustration and reconciliation of youth in the era of identity confusion after 6·4. The characters in the film did not mention a single word about the state power that made them do it. based on the characteristics of women in northeast China and the murder that occurred around a woman with a beauty that was not like a laundry employee. Centered around the unresolved slice murder case, expressed human moral ambiguity that does not distinguish good fortune from human instinct for struggle for survival, and portrayed the scenery of a very cold northeast small city. But it does not show any criticism of the crime. Based on the true story of the 2000s, the portrays the uncomfortable aspects of China that established Chinese socialism. A film composed of four short episodes conveys the destiny set by God.

Messianism in Civilizational History: The Transformation of the Buddhist Messiah via Maitreya

  • DINH Hong Hai
    • 대순사상과 동아시아종교
    • /
    • 제3권2호
    • /
    • pp.71-92
    • /
    • 2024
  • The world we live in is becoming more convenient thanks to the inventions of science and technology. Still, the world is also becoming more and more unpredictable with the current situation of VUCA (Volatility, Uncertainty, Complexity, Ambiguity). The Covid-19 pandemic brought the biggest global disaster ever with 774,631,444 infected people and 7,031,216 deaths (WHO on February 11, 2024) but it seems that humanity is gradually forgetting this disaster. Meanwhile the economic stimulus packages worth trillions of dollars from governments after the pandemic have further caused the world debt bubble to swell. The bubble burst scenario is something that many economic experts fear. Apparently, in the transitional period of the early decades of the 21st century, the world's economic, cultural, political, social, natural, and environmental aspects have undergone profound transformations: from the real estate and finance crises in the United States since 2008; through the melting of the Arctic ice over the past several decades; to the double disaster of the earthquake and tsunami in Japan in 2011. Especially, in the context of the world economic crisis after the COVID-19 pandemic, the human achievements of the past thousands of years are in jeopardy of being wiped out in an instant. Many people are predicting a bad scenario for a chain collapse. Facing the signals of an imminent economic catastrophe based on the appearance of "the Gray Rhino, Black Swan and White Elephant," many drawn in by Eschatological thought declare that Doomsday will occur shortly. This is the time for many other people to hope for the incoming Messiah. The Messiah is said to appear when people feel despair or suffer a great disaster because faith in the Savior can help them overcome adversity mentally. This research will find out how adherents of Buddhism view and deal with civilizational crises by examining history via symbols associated with Maitreya as based upon the Buddhist Messiah, Maitreya.

HPLC를 이용한 카페인의 분석법 개발 및 시판 식품중 함유량 조사 (Development of Analysis Method of Caffeine and Content Survey in Commercial Foods by HPLC)

  • 김희연;이영자;홍기형;이철원;김길생;하상철
    • 한국식품과학회지
    • /
    • 제31권6호
    • /
    • pp.1471-1476
    • /
    • 1999
  • 식품중 분석법에 대한 공정 시험법이 확립되어 있지 않은 카페인에 대해 우리 실정에 적용 가능한 시험방법을 개발, 확립함과 동시에 확립된 시험방법을 토대로 우리나라 국민들의 카페인 식이섭취 실태파악의 기초자료로 활용하고자 식품중의 카페인 함량을 측정하였다. 카페인 정량은 Sep-pak $C_{18}$ cartridge를 이용한 간단한 전처리를 통해 효과적으로 불순물을 제거한 후 메틸알콜-초산-물(20 : 1 : 79)을 이동상으로 하고 ${\mu}-Bondapak\;C_{18}$ 칼럼을 사용하여 파장 280 nm에서 고속 액체크로마토그라피분석을 행하였다. 동 조작조건에서 조사대상 식품군 별인 다류, 아이스크림, 가공유류, 과자류 중 카페인 무함유 식품인 감잎차, 바닐라아이스크림, 우유, 쿠키, 캔디, 사이다를 대상으로 회수율을 검토한 결과는 각각 99.10%, 98.93%, 99.37%, 99.17%, 99.50% 및 99.23%이었고 검출 한계는 $0.1\;{\mu}g/mL$였다. 또한 시중에 유통되고 있는 다류 15종 82품목, 아이스크림 1종 4품목, 가공유류 1종 2품목, 과자류 4종 13품목 및 청량음료 1종 13품목 등 총 22종 114품목을 조사대상 식품으로 하여 식품의 카페인 함량을 분석한 결과는 다음과 같다. 커피중 자판기용커피는 37.50 mg/g, 원두커피는 12.24 mg/g, 인스탄트커피는 19.74 mg/g, 탈카페인 커피는 3.38 mg/g이었으며, 녹차는 leaves(common grade)가 26.10 mg/g, leaves(crude)는 17.00 mg/g, tea bag은 16.30 mg/g이었고, 홍차는 분말에서 16.65 mg/g, tea bag은 10.80 mg/g이었다. 우롱차는 tea bag에서 11.25 mg/g이었으며, 코코아차, 기타 다류인 오가피차, 당귀차 칡차, 두충차, 둥굴레차, 영지차, 생강차, 명일엽차, 감잎차 및 쌍화차 등에서는 검출되지 않았다. 캔음료 중 캔커피 $0.18{\sim}0.75\;mg/g$, 캔녹차 0.11mg/g, 캔우롱차 0.06mg/g, 콜라 $0.06{\sim}0.11\;mg/g$이었으며, 아이스크림 중 커피 아이스크림 $0.05{\sim}0.44\;mg/g$ 초콜릿 아이스크림 $0.04{\sim}0.29\;mg/g$이었고, 가공유류중 저지방 커피우유 0.39 mg/g 및 초콜릿우유 0.04 mg/g이었다. 과자류중 초콜릿함유 과자류는 0.40mg/g 및 비스킷 $0.18{\sim}0.30\;mg/g$이었으며, 초콜릿과 캔디는 각각 $0.40{\sim}1.80\;mg/g$$0.10{\sim}0.47\;mg/g$이었다. 이상의 결과로서 본 시험법은 간단하고 신속하게 다량의 시료를 처리할 수 있는 분석방법으로서 식품중 공정시험법으로 적용할 수 있으며, 또한 본 분석결과를 토대로 우리나라 국민들의 카페인 식이 섭취 실태파악에 기초자료로서 활용이 기대된다.

  • PDF

가정내 응급처치를 위한 민간요법 (Folk Remedies for First Aid at Home)

  • 강현숙;조결자
    • 동서간호학연구지
    • /
    • 제3권1호
    • /
    • pp.17-26
    • /
    • 1998
  • The purposes of this study were to identify the contents, frequency of use, and the rationales of folk remedies frequently used for first aid at home for stomachache, vomiting, strain, food poisoning, vaginal bleeding, or wounds of snake or dog bite, or bee sting. As the method of the study, data were collected by conducting a questionnaire of 185 persons, who filled it out or who were interviewed from May to August in 1998. The collected data was analyzed by using frequency and the rationales for the contents of the folk remedies were described base on literatures. The results were as follows,. 1. The folk remedies for stomachache in frequency order were 'warming the abdomen', 'rubbing the abdomen with a hand', or 'pricking a finger to bleed', which have the rationals. 2. The folk remedies for vomiting in frequency order are 'drinking water of watery radish' and 'pricking a finger to bleed', which have the rationales. 3. The folk remedies for strain in frequency order are 'soaking the affected area into cold water or applying an ice pack' and 'after soaking jasmine in water, making a dough with flour, and then attaching it on the affected area', which have the rationales, Additionally, although the frequencies are low, 'drinking brewed Achyranthis Radix' and 'applying brewed leaves and stalks of Sambuci Cortex' have the rationales. 4. The folk remedies for food poisoning in frequency order are 'drinking black beans and licorice brewed together' and 'eating mung beans', which have the scientific grounds. 5. The folk remedies for bloody discharge in frequency order are 'drinking brewed lotus root' and 'eating boiled chicken stuffed with root of bell-flower'. However, 'drinking brewed Thujae orientalis Folium' has the rationales. 6. The folk remedy for snake bite wounds that has the scientific grounds is 'sucking blood by a person without hurt in the mouth'. However, quite a lot of people apply alum or soy paste, which has no rationales. 7. The folk remedies for the bee sting in frequency order are 'after removing the sting, applying soy paste or sauce' and 'applying saliva'. No rationales for 'applying saliva' have been found. 8. The folk remedy for the dog bite wound that has the rationales is 'applying juice of leaves or stalks of Xanthii Fructus'. However, 85% of surveyed people use remedies that have no scientific grounds, such as 'applying burnt dog hair mixed with (sesame) oil' and 'applying soy paste or sauce'. Various materials are used in folk remedies for first aid treatment as shown above. Some of the folk remedies have the rationales since their medicinal actions have been found. However, the medicinal actions of the majority have not been found, but only known that they are effective, Especially for the materials except botanical drugs, they are used without knowing the effects since their components and pharmacognosies have not been described in any literature. The results of this research may be used for materials to educate the surveyed people or to consult them. Accordingly, the folk remedies that have the rationales are required to continue to study to find out the effects.

  • PDF

열처리 온도가 전기방사방법을 이용하여 제조한 PEMFC용 TiO2 담체의 물리적 특성에 미치는 영향 (Effects of Calcination Temperature on Characteristics of Electrospun TiO2 Catalyst Supports for PEMFCs)

  • 권초롱;유성종;장종현;김형준;김지현;조은애
    • 한국수소및신에너지학회논문집
    • /
    • 제24권3호
    • /
    • pp.223-229
    • /
    • 2013
  • Polymer Electrolyte Membrane Fuel Cell (PEMFC) is a power generation system to convert chemical energy of fuels and oxidants to electricity directly by electrochemical reactions. As a catalyst support for PEMFCs, carbon black has been generally used due to its large surface area and high electrical conductivity. However, under certain circumstances (start up/shut down, fuel starvation, ice formation etc.), carbon supports are subjected to serve corrosion in the presence of water. Therefore, it would be desirable to switch carbon supports to corrosion-resistive support materials such as metal oxide. $TiO_2$ has been attractive as a support with its stability in fuel cell operation atmosphere, low cost, commercial availability, and the ease to control size and structure. However, low electrical conductivity of $TiO_2$ still inhibits its application to catalyst support for PEMFCs. In this paper, to explore feasibility of $TiO_2$ as a catalyst support for PEMFCs, $TiO_2$ nanofibers were synthesized by electrospinning and calcinated at 600, 700, 800 and $900^{\circ}C$. Effects of calcination temperature on crystal structure and electrical conductivity of electrospun $TiO_2$ nanofibers were examined. Electrical conductivity of $TiO_2$ nanofibers increased significantly with increasing calcination temperature from $600^{\circ}C$ to $700^{\circ}C$ and then increased gradually with increasing the calcination temperature from $700^{\circ}C$ to $900^{\circ}C$. It was revealed that the remarkable increase in electrical conductivity could be attributed to phase transition of $TiO_2$ nanofibers from anatase to rutile at the temperature range from $600^{\circ}C$ to $700^{\circ}C$.

서울시내(市內) 일부(一部) 저소득층(低所得層) 비급식국민학교(非給食國民學校) 아동(兒童)의 식생태(食生態)에 관한 연구(硏究) (An Ecological Survey of Food and Nutrition of Children attending an Elementary School without a School Lunch Program, in a Low Income Group of Seoul)

  • 정상진;최선혜;모수미;이수정
    • 한국식생활문화학회지
    • /
    • 제6권4호
    • /
    • pp.369-380
    • /
    • 1991
  • A study of eating behavior was conducted among 274 children of Nan Hyang elementary school, located in low income area of Seoul, where a school lunch program is not operated. During weekdays, 19.6% of children ate breakfast and 18.4% ate supper alone or with their siblings. The school provided boxed lunches for 10.5% of the children with governmental funds, who were chosen by the school based on their household income. But the percentage of the children skipping breakfast was 14.6%, lunch 10.3% and supper 8.0%. The results of nutritional analysis of the children who had three meals a day and those of children skipped one of the regular meals were compared. The group who had three meals consumed more nutrients except vitamin C than the group skipped meal (p<0.01). Most common meal pattern was consisted of cooked rice, Kimchi and side dishes. When the children didn't have afternoon classes, 10.0% of the children ate Ramen only at home without any side dishes. Among the protein sources, the beans and bean products were the most common items. When we studied the three different lunches such as A) the boxed lunches provided by school, B) the boxed lunches from home and C) the lunches ate at home, the A) lunches provided the most common items. When we studied the three different lunches such as A) the boxed lunches provided by school, B) the boxed lunches from home and C) the lunches ate at home, the A) lunches provided the milk products, fruits, ice cakes${\cdots}$etc. Their favorite foods were fruits, yoghurt, Chinese black noodle, and sweet potatoes whereas being not prefered foods, were aromatic vegetables. It seemed that the increasing rate of working mothers and the overflooding of instant foods have caused to neglect children's meal management. To solve these problems, nutrition education and extend of school lunch programs should be emphasized.

  • PDF

Late season commercial mosquito trap and host seeking activity evaluation against mosquitoes in a malarious area of the Republic of Korea

  • Buekett, Douglas-A.;Lee, Won-Ja;Lee, Kwan-Woo;Kim, Heung-Chul;Lee, Hee-Il;Lee, Jong-Soo;Shin, E-Hyun;Wirtz, Robert-A.;Cho, Hae-Wol;Ckaborn, David-M.;Coleman, Russel-E.;Kim, Wan-Y;Klein, Terry-A.
    • Parasites, Hosts and Diseases
    • /
    • 제40권1호
    • /
    • pp.45-54
    • /
    • 2002
  • Field trials evaluating selected commercially available mosquito traps variously baited with light, carbon dioxide, and/or octenol were conducted from 18-27 September 2000 in a malarious area near Paekyeon-ri (Tongil-Chon) and Camp Greaves in Paju County, Kyonggi Province, Republic of Korea. The host-seeking activity for common mosquito species, including the primary vector of Japanese encephalitis, Culex tritaeniorhynchus Giles. was determined using hourly aspirator collections from a human and propane lantern-baited Shannon trap doting hours when temperatures exceeded $15^{\circ}C$. The total number of mosquitoes and number of each species captured during the test was compared using a block design. Significant differences were observed for the total number of mosquitoes collected, such that, the Mosquito MagnetTM with octenol > Shannon trap > ABC light trap with light and dry ice > Miniature Black Light trap (manufactured by John W. Hock) $\geq$ New Jersey Trap > ABC light trap with light only. Significant differences in numbers collected among trapes were noted for several species including: Aedes vexans (Meigen), Anopheles lesteri Baisas and Hu. An. sinensis Weidemann, An. sineroides Yamada, An. yatsushiroensis Miyazaki. Culex pipiens pallets Coquillett L., Cx. orientalis Edwards and Cx. tritaeniorhynchus. Host-seeking activity for most common species showed a similar bimodal pattern. Results from these field trap evaluations can significantly enhance current vector and disease surveillance efforts especially for the primary vector of Japanese encephalitis, Cx. tritaeniorhunchus.

동절기 피해의 이해와 겨울철 골프장 관리: 리뷰 (Winterkill and Strategy of Golf Course Management: A Review)

  • 이상국
    • 아시안잔디학회지
    • /
    • 제25권2호
    • /
    • pp.133-137
    • /
    • 2011
  • 동절기 피해는 겨울철에 나타나는 피해의 형태로 유형에 따라 저온피해, 건조피해, 관부수화, 그리고 동절기 병 발생등이 있다. 저온피해는 대기온도와 토양온도에 의해 그 피해가 발생하는데 토양온도가 관부의 생육에 더 큰 영향을 미치기 때문에 그 피해의 정도가 더 심하게 발생한다. 관부수화는 세포내결빙에 의해 발생하는 피해로 세포막을 파괴하며 결과적으로 세포내 조직을 탈수시키게 된다. 저온건조는 동절기 기간동안 식물체의 잎 혹은 식물전체에 건조로 인한 피해가 나타나 고사에 이르게 되는 피해를 말한다. 동절기 피해를 예방하기 위해 가을철 인산과 칼륨의 시비가 동절기 피해에 대한 내성을 증진시키는 역할을 하게 된다. 또한 피복재의 사용이 동절기 피해를 최소화 하는 기능을 하는데 그 종류는 여러가지가 있으며 겨울철 잔디위에 쌓인 눈도 대기온도로부터 토양온도를 유지하는 피복재 역할을 하게 된다. 동절기 피해를 최소화 하기 위한 방법으로 통기와 배토의 방법이 있다. 통기와 배토는 모두 주로 대취층의 두께를 줄이기 위한 방법으로 사용이 되고 또한 겨울철 배토를 위해 사용되는 검은색 모래는 토양에 잔존해 있는 얼음을 녹이고 토양온도를 유지해주는 역할을 하게 되므로 피복재와 같이 동절기 피해를 최소화 하는 역할을 하게 된다.

열매체 순환수 배관이 매설된 콘크리트 도로 포장체의 표면 온도 변화와 방열량 평가 (Evaluation of Surface Temperature Variation and Heat Exchange Rate of Concrete Road Pavement with Buried Circulating Water Piping)

  • 손병후;김용기
    • 한국지열·수열에너지학회논문집
    • /
    • 제19권3호
    • /
    • pp.1-13
    • /
    • 2023
  • Hydronic heated road pavement (HHP) systems have been well established and documented to provide road safety in winter season over the past two decades. However, most of the systems run on asphalt, only a few are tested with concrete, and there rarely is a comparison between those two common road materials in their performance. The aim of this study is to investigate the thermal performance of the concrete HHP systems, including surface temperature variations of experimental pavements in winter season. For preliminary study a small-scale experimental system was installed to evaluate the heat transfer characteristics of the concrete HHP in the test field. The system consists of 3 concrete slabs made of 1 m in width, 1 m in length, and 0.25 m in height. In these slabs, circulating water piping was embedded with different pipe depths of 0.08 m (Case A), 0.12 m (Case B), and 0.20 m (Case C) and same horizontal space of 0.16 m. Heating performance in winter season was tested with different inlet temperatures of 25℃, 30℃, 35℃ and 40℃ during the entire measurement period. Overall, the surface temperature of the concrete HHPs remained above 3℃ in all experimental conditions applied in this study. The results of the surface temperature measurement with respect to the pipe depth showed that Case B was the highest among the three cases. However, the closer the circulating water pipe was to the pavement surface, the greater the heat exchange rate. This results is considered that the heat is continuously accumulated inside the pavements and then the temperature inside the pavements increases, while the amount of heat dissipation decreases as the temperature difference between the inlet and outlet of circulating water decreases. In this preliminary test the applicability of the concrete HHP on road deicing was confirmed. Finally, the results can be used as a basis for studying the effects of various variables on road pavements through numerical analysis and for conducting large-scale empirical experiments.