• Journal of the Korean Chemical Society
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• v.21 no.4
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• pp.293-303
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• 1977

Cellulosic organic solid wastes such as bark and sawdust, and filter papers as a pure cellulose were pyrolyzed at $300^{\circ}C$ under nitrogen current and mixed current of nitrogen and air. Amounts of condensates collected in air, water, and dry ice-acetone cooling traps, noncondensable gases, and carbonized residues were surveyed. The components of volatile liquids condensed in dry ice-acetone trap were separated by means of gas chromatograph and identified by retention times and syringe reactions. Pyrolysis under nitrogen current produced 13.4∼29.6${\%}$ of tar, 0.01∼0.12${\%}$ of aqueous liquids, 0.24∼1.43${\%}$ of volatile liquids, 9.84∼42.41${\%}$ of noncondensable gases, and 44.0∼65.81${\%}$ of carbonized residues. Pyrolysis under mixed current decreased tar and condensable liquids, but increased noncondensable gases.Volatile liquids collected under nitrogen current separated into the same 19 components by Porapak Q column regardless of the materials and only difference among materials was relative amounts of components. Volatile liquids collected under mixed current separated into six components and mainly lower molecular weight compounds such as methanol and formaldehyde were produced. According to the retention times and syringe reactions, methanol, formaldehyde, acetone, acetaldehyde, acetic acid, and three other compounds presumably containing hydroxyl group in the molecular structure were identified out of 19 compounds.

• Korean Journal of Environment and Ecology
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• v.28 no.2
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• pp.113-122
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• 2014

This study was conducted to clarify the community characteristics of wintering waterbirds in Geum River from September, 2011 to March, 2012 (1st) and from September, 2012 to March, 2013 (2nd). 63 species of waterbirds including raptors were observed during the survey. 50 species of 188,673 individuals recorded during the first survey, and 56 species of 116,611 individuals were recorded during the second survey. The dominant species was high dominance dabbling ducks by Baikal Teals, Mallards, Spot-billed Ducks, Greater White-fronted Geese, Black-tailed Gulls and Common Shelducks. We classified the wintering waterbirds into 9 taxa based on the similar ecological characteristics and analyzed the correlation with temperature. As a result, dabbling ducks, diving ducks and raptors showed positive correlation and herons and waders showed negative correlation. Geese, swans and dabbling ducks were high habitat utilization ratio at the Geumgang estuary barrage upstream area, and diving ducks, herons, waders and gulls were high habitat utilization ratio at the Geumgang estuary barrage downstream area.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.6
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• pp.504-511
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• 1990

Weather data acquisition and potential evapotranspiration (PET) calculation procedure were investigated to support the agricultural development efforts in the mid-altitude mountainous region of Cheju Island. Automated weather stations (AWS) were installed at two points representing the east and the west of the study area. A personal computer was employed to collect the near-real time weather data from AWS through the public telephone line. Hourly data were available for solar radiation, air and soil temperature, relative humidity, wind speed and direction, and precipitation. Based on the data for the month of June 1989, daily climatic features were comparatively analyzed for the two areas and the Penman equation was used to calculate PET. Air temperature was higher by 1 to 2 degree C in the east due mainly to the higher solar radiation and partly to the Fohn effect caused by the daytime southwesterly blowing over Mt. Halla. Diurnal march of soil temperature lagged by 4 hours behind that of air temperature and the diurnal range for 10cm subsurface soil was 3 degree C. Wind was consistently stronger and a marked sea-land breeze circulation was detected in the west. Calculated PET values were higher in the east by 6% than in the west. Overall values from the east and the west of the mid-altitude mountainous region were higher by 30% than those of the coastal region, which were estimated from the Class A Pan evaporation measured by the Korea Meteorological Service Offices.

• Tuberculosis and Respiratory Diseases
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• v.40 no.5
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• pp.548-557
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• 1993

Background: Bronchiectasis is a irreversible disease, a lot of cases of which are associated with chronic bronchitis, pulmonary emphysema and bronchial asthma due to chronic recurrent pulmonary infection. Therefore, pulmonary functions in bronchiectasis may also vary with associated diseases or involved segments. Methods: For the evaluation of ventilatory dynamics in bronchiectasis with respect to the pathoanatomic types of bronchiectasis and the degree of dyspnea, a total of 93 cases comprising 45 cases of tubular, 30 saccular and 18 mixed type of bronchiectasis whose clinical diagnosis was confirmed by bronchography were analyzed retrospectively. They were also divided into two groups: those with Hugh-Jones dyspnea grade 1 & 2 (group I) and those with Hugh-Jones dyspnea grade 3 & 4 (group II). Pulmonary functions tested in this study were analyses of curves of forced expiratory volume and flow-volume, and determinations of maximal voluntary ventilation and closing volumes. Results: The results were as follows; 1) The vital capacity and parameters reflecting expiratory flow rate except PEF were significantly reduced in saccular and mixed type than that in tubular type of bronchiectasis. 2) In saccular and mixed type, the maximal voluntary ventilation tended to decrease while CV/VC tended to increase. 3) As the degree of dyspnea became serious, the involved segments were progressively increased. In contrast, ventilatory functions were significantly reduced in proportion to the severity of dyspnea. Conclusion: These findings suggest that in bronchiectasis, there be obstructive ventilatory impairment combined with mild restrictive ventilatory impairment, which becomes more prominent in saccular and mixed type and also as the degree of dyspnea progresses.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.715-721
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• 2018

This study examined energy saving and elevating the worker's neuro energy (comfort, concentration, physical, and psychological stability) by compensating for the unpleasant tactile sensation to stimulate auditory and olfactory senses and reduce energy consumption. The experiment was conducted in an environment test room under the test conditions of temperature $25[^{\circ}C]$, relative humidity 50[RH%], illumination 1,000[lux] and air current speed 0.02[m/sec] by stimulating the auditory senses with a 1/f change in rhythm and the olfactory senses with an aroma scent. The experiment utilized the method of EEG, which evaluates human body's psychological status via tactile means, and the method of the vibra image, which evaluates the learning abilities, HRV and human body's psychological status via non-tactile means. The subjects were selected as eight university students (four males and four females) in their 20s, the type that have high relative ${\alpha}$(8~13[Hz]) activation in occipital lobe, which brings the highest level of mind stability and concentration, who had no difficulty in physical activities. The subjects' posture and physical activity was fixed to 1met - when the subjects are seated and relaxing in a comfortable environment - and their clothes condition was standardized as 0.7clo. As a result, the sentimental and psychological stability and concentration were the highest in the multisensory stimulation of jasmine scent and change rhythm of an a=1.106 sound source. In addition, under this condition, the relative $M{\alpha}$ and relative $M{\beta}$ increased by 70.49[%] and 89.72[%], respectively; the HRT decreased by 39.09[%]; and the fatigue and tension/anxiety decreased by 36.85[%] and 15.54[%], respectively.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.73-87
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• 2004

This study was carried out on Sihwa reclaimed area from January to December in 2003. We observed total 169,351 individuals of 70 species(22 species of waders, 9 species of egrets and 5 species of gulls). Waterbird population was the largest in March(95,465 individuals) and was the smallest from April to June(less than 7,000 individuals). The most dominant species was Pintail(Anas acuta: 58,627 individuals, 34.6%) and other species were Mallards(Anas platyrhynchos: 24.5%), Common Pochards(Aythya ferina: 13.8%), Black-tailed Gulls(Larus crassirostris: 6.1%), Spotbill Ducks(Anas poecilorhyncha: 5.0%) and Greater Scaups(Aythya marila: 2.69%). Sihwa reclaimed area supported many kinds of protected species such as Chinese egrets(Egretta eulophotes), Black-faced Spoonbills(Platalea minor), Eurasian Spoonbills(Platalea leucorodia), Mute Swans(Cygnus olor), Whooper Swans(Cygnus cygnus), and Eurasian Oystercatchers(Haematopus ostralegus). They foraged at waterside of Sihwa lake and rested at reclaimed area. Particularly, Eurasian Oystercatchers bred in habitats with Salicornia herbacea and Suaeda japonica. Reclamation of mud flats and construction of roads, transmission towers and tide embankments disturbed waterbirds in breeding and foraging. We suggest that waterbirds are protected in different action plans according to their status such as breeding, passaging and wintering birds. Maintaining of waterside and swamps in Sihwa reclaimed area will be useful for breeding waterbirds. It is needed to make a protect zone for ecological connecting belt from Oeji isarea, Hyeong isarea, Eum isarea to upper channel on Sihwa lake.

• Journal of Science of Art and Design
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• v.9
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• pp.89-115
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• 2006

한국근대미술은 유화 도입기인 1910년대를 한국미술사의 중요한 시작점이다. 1910년경부터 형성되기 시작한 유화 도입배경과 그것이 당시 사회의 절실한 요청에 의한 것이었는지, 그렇다면 그것이 무엇인지 규명하는 것이 한국근대미술 초기를 알 수 있는 중요한 문제일 것이다. 일본근대 유화의 역사는 국수주의와 서구주의 물결이 반복하는 과정에서 점차 일본화된 소재의 등장과 일본정서에 부합하는 화풍을 만들어 나가게 되는 것이 1890년대부터 1910때까지의 일본근대 유화계의 상황이라고 할 수 있다. 이 시기를 다시 요약하면 외광파와 인상파가 절충된 양식에 일본의 메이지낭만주의에 부합하는 소재 즉 일본전통이라고 할 수 있는 풍경에 대한 애착 등이 전체 유화의 기류로 나타나는 시기라고 할 수 있다. 실제 새로운 문화의 하나였던 유화는 점차 세계의 다양한 미술사조 속에서 일본화다운 것으로 발전하는 모습을 보여준다. '구로다 세이키'(黑田淸輝) 이전에 이미 형성되었던 일본근대 유화양식과 구로다의 외광파 양식, 또 외광파가 일본 근대유화의 주류로 형성하게 되는 계기, 여기에 프랑스에서 직접 배워 온 작가들에 의한 인상파 도입 그리고 일본 '메이지낭만주의'(明治浪漫主義)의 등장으로 인한 사회 환경구조의 변화 속에서 양성된 그들의 절충양식의 초기유학생들에게 큰 영향을 미쳤다. 우리근대미술은 '민족적 자부심'과 '민족적 열등감'이 동시에 존재하는 사회적 배경논리에서 출발하지 않으면 안 된다. 즉 근대미술의 사상적 배경에는 민족 개량주의적 발상과 계몽주의적 문화 활동에 있었다고 할지라도 근본적으로는 미술자체를 근대사회 발전의 연장선 속에서 파악하지 못했고, 따라서 미술자체를 새로운 문명수입이라는 근대적 풍물 정도로만 파악했던 것이 어쩔 수 없는 근대미술의 한계라고 할 수 있다. 이 시기에 미술을 주목한 이유는 근대적 사회로 발전하기 위한 하나의 필수적인 요소로 미술자체를 파악하고 나아가, 식산흥업(殖産興業)의 수단으로 인식 했던 신지식층에 의해 시작되었다고 할 수 있다. 문명의 발달이 미술의 발달에서 연원한다는 '미술문명론' 같은 시각이 미술자체가 성격이나 창작의 방향과는 무관하게 어떤 미술이든 그것을 활성화시키는 것이 근대 즉 문명화된 세계로 나아갈 수 있다고 하는 관점에서 비롯된 것이라고 할 수 있다. 한국근대미술에 있어서 아카데미즘 역시 일본근대미술과 불가분의 관계가 있음을 부인할 수 없다. 초기유학생들은 그 당시 일본의 잡지나 화단에서 일어나는 여러 가지 시안들을 피상적으로 이해하는 정도였을 것으로 파악할 수 있다. 이러한 맥락에서 보면 한국근대미술에 있어서 초기유학생들의 작품과 그 이후 선전에서 입선하는 작품들은 일본아카데미즘의 영향 밑에 있다고 해야 할 것이다. 일본 근대 유화에서 형성된 외광파의 요소와 인상파 요소들이 일본 낭만주의로 표면화된 하나의 일본근대 유화의 형식 그대로가 한국아카데미즘의 성격을 결정하고 있다고 할 수 있다. 게다가 1922년에 시작된 선전은 심사위원 대부분이 동경미술학교 교수이면서 구로다의 제자이거나 동료였다는 것은 이러한 사실을 더욱 확고하게 뒷받침하고 있는 것이다. 초기유학생들이 남긴 작품들은 완전한 인상파에 대한 지식이나 깊은 자아의식을 가지고 제작된 것은 아니라, 일본 동경미술학교에서 가르치고 있었던 것들을 그대로 수용했다고 할 수 있다. 따라서 이들의 그림은 구로다의 외광파라고 부르는 것들의 영향보다는, 인상파를 보고 배웠던 동경미술학교 교수들의 영향을 더 많이 받았다고 할 수 있다. 그리고 이들의 영향은 그대로 한국 근대미술의 아카데미즘을 형성하는데 커다란 영향을 미치고 있음을 부인할 수 없다.

• Proceedings of the KWS Conference
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• 2009.11a
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• pp.30-30
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• 2009

GTA 용접에서 용입, 용접부의 크기와 형상이 형성되는 아크 물리학적 현상을 이해함에 있어서 에너지 분포특성은 매우 중요한 인자이다. GTA 용접에서 아크 길이의 변화와 사용된 실드 가스 종류에 따라 음극인 텅스텐 전극 팁의 아크 루트 직경에 큰 변화를 주며, 양극인 모재 쪽의 에너지 분포에 영향을 미치며 된다. 기존의 연구자들은 저전류나 중전류 영역의 GTA 용접에서 텅스텐 전극의 선단각과 용입 형태와 의 관계를 plasma 기류 등에 의해 고찰하거나, 최대 아크압력에 미치는 전극형상의 영향에 대하여 연구하였다. 용접부에 작용하는 아크 압력의 분포는 결국 운동 에너지의 분포이다. 기존의 연구자들에 비하여 보다 간편한 실험을 통하여 양극 모재위의 아크 압력에 의한 에너지 분포특성을 규명하는 연구가 필요하다. 본 연구의 목적은 GTA 용접의 용접전류 100A~200A 영역에서 아크 길이 변화와 Ar 가스에 $H_2$ 혼합에 따른 측정된 아크 압력으로부터 기존연구자들의 아크 물리학적 결과들을 활용하여 양극 모재 위에 작용하는 전류밀도 분포를 유도하는 것이다. GTA 용접에서 아크 길이의 변화와 Ar 가스에 $H_2$ 혼합은 아크 압력분포에 큰 영향을 미치며, 이에 따라 에너지 분포특성에 많은 영향을 미친다. 아크 길이가 증가함에 따라 Ar가스와 $H_2$ 혼합가스의 에너지 분포는 감소하였고, Ar가스에 $H_2$ 혼합에 의해 아크 에너지가 증가하여 용입형상에 큰 영향을 미칠 것으로 판단된다. 이에 대한 연구는 향후 GTA 용접 응용분야 확대 적용될 것이며, 아크 물리학 연구에 기초적이고 아주 중요한 과학적인 자료가 될 것으로 판단된다.

• Tunnel and Underground Space
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• v.28 no.1
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• pp.38-58
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• 2018

The ventilation system plays a crucial role in underground mine safety. The main objective of the ventilation system is to supply sufficient air to dilute the contaminated air at working places and consequently provide tenable environment during the normal operation, while it also should be capable of controlling the fire propagation and facilitate rescue conditions in case of fire in mines. In this study, a smoke control fan was developed for the auxiliary ventilation as well as the fire smoke exhaust. It works as a free-standing auxiliary fan without tubing to dilute or exhaust the contaminated air from the working places. At the same time, it can be employed to extract the fire smoke. This paper aims to examine the smoke control efficiency of the fan when combined with the current ventilation system in mines. A series of the site experiments and numerical simulations were made to evaluate the fan performance in blind entry development sites. The tracer gas method with SF6 was applied to investigate the contaminant behavior at the study sites. The results of the site study at a large-opening limestone mine were compared with the CFD analysis results with respect to the airflow pattern and the gas concentration. This study shows that in blind development entry, the most polluted and risky place, the smoke fan can exhaust toxic gases or fire smoke effectively if it is properly combined with an additional common auxiliary fan. The venturi effect for smoke exhaust from the blind entry was also observed by the numerical analysis. The overall smoke control efficiency was found to be dependent on the fan location and operating method.

• Korean Journal of Organic Agriculture
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• v.19 no.1
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• pp.93-107
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• 2011

This research was carried out to investigate invertebrate fauna with organic and conventional pear orchards, which used four collected methods; soil sampling for soil microorganism, pitfall, malaise, and black light trap for over ground species. Collected species were 37 species, 1,184 individuals in organic and 28 species, 501 individuals by soil sampling in conventional pear fields. Those were 38 species, 646 individuals and 29 species, 440 individuals by pitfall trap, 55 species 650 individuals and 47 species, 508 individuals by malaise trap, and 23 species, 201 individuals and 9 species, 42 individuals by black light trap. Collembola was collected 389 individuals in organic which was 5 times than in conventional in soil sampling. In pitfall trap, that was 183 individuals which was 3 times. The diversity indices of organic pear orchards were 1.956 in May, 2.638 in August and those of conventional was 1.426 in May, 2.011 in August in soil sampling. In pitfall trap, the dominant species were spiders, collembollan, and coleopteran. Among Coleoptera, indicator insects for the evaluation of agricultural environment suggested were Eusilpha jakowelewi as organic pear orchard and Anisodactykus punctatipennis and Pheropsophus jessoensis as conventional. Malaise trap was collected dominant species as Diptera and Hymenoptera of Braconidae and Ichneumonidae. The diversity indices of organic pear orchards were 2.952, 3.120, and 2.010 in pitfall, malaise and black light trap in over ground invertebrate sampling. The highest diversity was in malaise trap. The higher diversity indices, the lower dominance indices.