• 대한건축학회논문집:계획계
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• 제34권2호
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• pp.3-11
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• 2018

Korea has achieved a rapid economic development and with the increase in population and national income and the expansion of social and economic activities, energy consumption has rapidly increased too. Energy consumption per head has constantly increased and currently, power consumption per head is 7.5 times bigger than in 1985. Buildings occupy 25% of total energy consumption and especially, 50% of total energy is consumed for heating and cooling. In this situation, multi-family housing, which has constantly been increased, has an energy saving rate of 1.9%, which is the lowest level and this makes the government's energy policy for sustainable energy system development useless. Besides, energy consumption leads to secondary problems, such as air, water and marine pollution and heat pollution and wastewater/drainage and the increased use of fossil fuel is a fundamental reason for ozone layer destruction and global warming. Therefore, efficient energy consumption plans are required. This study aims to analyze energy performance in each block type of high-rise and diversified multi-family housing that accounts for 60% of all the housing forms, depending on the variations in stories through BIM-based energy simulation. For this study, four representative block types were selected, based on the multi-family floor plan, which is certified for energy performance evaluation and they were applied to the floor plan of a multi-family house that is scheduled to be built. Then BIM modeling was conducted from the fifth story to the 40th story at an intervals of 5 stories and based on the finding, energy characteristics of each block type and energy performance depending on the variations in stories were analyzed. It is considered that this would serve as objective data for block type and block story decision of energy performance-based multi-family housing.

• 한국전자통신학회논문지
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• 제16권6호
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• pp.1263-1270
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• 2021

최근 음식 문화생활은 소비자들이 직접 요리를 하는 트렌드로 변화하고 있으며 인덕션 조리기구의 사용비율이 증가하고 있다. 이에 본 연구에서는 요리 인구 증가에 따른 요리의 편리성을 향상하도록 인덕션 조리기구의 안전성 개선을 위한 기능보조 디바이스 개발을 제안한다. 제안한 디바이스는 앱을 통해 IoT와 연동된다. 앱을 통해 디바이스는 인덕션의 화력 조절과 시간 예약을 제어할 수 있다. 또한, 조리 시 용기의 물 넘침을 방지하기 위해 초음파 센서를 사용하고, 미세먼지 측정 센서를 통해 사용자가 안전하게 인덕션을 사용할 수 있다. 제작한 디바이스를 통해 실제 조리 상황을 가정하여 연구를 진행한다. 본 연구는 디바이스를 통해 조리 시에 사용자의 피로감을 줄이고 초과 조리, 또는 물 넘침과 같은 위급상황 시에 사용자를 위한 안전성 개선을 확인하였다.

• Journal of Chest Surgery
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• 제13권3호
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• pp.212-218
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• 1980

A severe crushing injury of the chest produce a very striking syndrome referred to as traumatic asphyxia. This syndrome is characterized by bluish-red discoloration of the skin which is limited to the distribution of the valveless veins of the head and neck. And also if it is characterized by bilateral subconjunctival hemorrhages and neurological manifestations. But these clinical entities faded away progressively in a few weeks. Apporximately 90% of the patients who live for more than a few hours will recover from traumatic asphyxia when it occurs as a single entity. And so, death results from either severe associated injuries of from subsequent infection, rather than from pulmonary or cardiac insufficiency in traumatic asphyxia. We have experienced 4 cases of traumatic asphyxia with severe crushing thoracic injuries at department of the chest surgery, Captial Armed forces General Hospital during about 3 years from April 1977 to Aug. 1980. The 1st 22 year-old male was struct 2$\frac{1}{2}$ ton truck on the road and was transferred to this hospital immediately. He had taken tracheostomy due to severe dyspnea with contusion pneumonia and for removal of a large amount of bronchial secretion. The 2nd case was 23 year-old male who was got buried in a chasm. In this case, the heavy metal post tumbled over him back while at work. The 3rd case was 39 year-old male who leapt out of a window in 5th story while fire broke out in living room by oil stove heating. He had multiple rib fracture with right hemothor x and right colle's fracture and pelvic bone fracture. The last 22 year-old male was run over by a gun carriage. The wheel of this gun carriage passed over his thorax and right chin. He was brought to this hospital by helicopter. when he was first examined at emergency room, he was in semicomatose state and has pneurmomediastinum with multiple rib fracture and severe subcutaneous emphysema. As soon as he arrived, bilateral closed thoracostomy was performed and cardiopulmonary resuscitation was done. In hospital 8th weeks, chest series showed fibrothorax in right side even if chest wall stabilized. All 4 cases had multiple petechiae over their facees and chest and bilateral subconjunctival hemorrhages referred to as traumatic asphyxia. 3 cases except one case who received splenectomy, had been suffered from contusion pneumonia and had been treated with respiratory care. In these 3 cases, they had warning of impending injury before accident, and took a deep breath hold it and braces himself. And also, even if he had not impending fear in remaining one case, he had taken a deep breath and had got valsalva maneuver for pulling off the heavy metal post. Intrathoracic pressure rose suddenly and resulted to traumatic asphyxia in this situation. All these cases were recovered completely without sequelae except one fibrothorax, right.

• 한국환경교육학회지:환경교육
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• 제3권1호
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• pp.130-140
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• 1992

The purpose of this study was to survey the trends of waste products in schools, its gathering and disposal, identification of problems and to analyze its disposal. Moreover, this study was aimed at basic suggestions about the establishment and plans of waste environmental education. 98 public primary and secondary schools were surveyed in Seoul during the month of March and April, 1991. Information was collected from each educational association by random sampling. Questionaries were used for this survey. To understand the disposal status of school waste and its reforms, this study surveyed the amount of waste by products, their origin and analyzed the disposal by type, one number of schools and teachers involved. The dump sited and disposal methods of school waste, its problems, and the status of school waste educations were researched, and ideal disposal methods and plans for waste education were suggested. The results were as follows. 1. The School's trash was produced by followings: paper, vinyle plastics, food, woods, metals, ceramics, glass, bottles, and ash from the heating system. The biggest cause of the school's waste as shown by the survey was a lack of environmental awareness(39.8%). The second biggest was the use of a one time use of disposable paper products(27.6%). 2. Waste collection by different grade levels were proven to be important but as you move from elementary to high school, the waste collecting operation decreased, in this connection between the students and waste collection itself it was significant on the other hand the teachers were not working as significant variables. 3. Of the school that collected waste 69.5 percent of the schools separately grouped common waste and recyclable waste. 25 schools(42.4%) received improvement on their environmental awareness of trash collection through this method. 4. From the number of disposal sites in surveyed schools, it was determined that the education of the necessity for separation of waste was performed in vain and accordingly the should require a real education in the future. 5. Regarding the method of disposal of waste the survey indicated that the #1 method of disposal was partial burning and the remains carried to a dump site by others(35,7%). In elementary schools the entire waste was taken by individuals to a dump site (33.3%). In high schools partial burning and then transported by individuals #1 in our survey(50%). 6. Relative to the problem of the treatment to waste, the emission of smoke from the burning was considered to be the #1 priority in our survey (62.3%) the problem of trash collection being delayed was 52.1%(1in our survey). 7. The present situation of environmental education of waste us lacking. Under present circumstances, the practice of public announcements for improvement and waste-paper collection has been going on vigorously but lacking in education as to the preparation of compositions for students the themes of public exhibitions, the organizing of voluntary associations should be part of the education system to reinforce student's awareness of proper waste disposal. 8. The most economical alternative for disposal was recycling usable waste or combustible material through a variety of education we can therefore educate students bring this education to their homes public servants will also be able to benefit in the waste disposal process with proper education. In conclusion we should intensify the systemical organization and the education of our waste disposal for a better environment.

• 유기물자원화
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• 제16권2호
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• pp.29-37
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• 2008

본 연구에서는 하수슬러지, 음식물쓰레기, 분뇨계 폐기물과 같은 고농도 유기성 폐기물의 고온 메탄 발효에 대하여 공정, 응용 현황 및 장 단점의 여러가지 측면에서 고찰이 이루어졌다. 고온 메탄 발효의 장점은 반응속도가 빠르고, 높은 부하량에서 처리가능하고, 병원성 미생물의 사멸율이 높고, 소화오니는 보다 위생적이었다. 그러나, 단점으로서는 발효시설을 가열하는데 많은 에너지를 요구하고, 저농도 유기성 폐기물에서는 잉여에너지를 얻을 수 없고, 발효처리 후 상등수 수질이 떨어지게 되며, 그 결과 배수처리에 부담이 된다. 특히, 고농도 메탄 발효의 경우 영양염 부족이나 ${NH_4}^+-N$에 의한 방해가 일어나기 쉬우므로, 이에 대하여 적절한 대안이 요구된다. 일반적으로 고온 메탄 발효는 고농도의 우분뇨와 음식물 유기성 폐기물의 좋은 처리 수단으로 고려되었다. 반대로, 폐기물 그 자체의 농도가 낮을 경우와 ${NH_4}^+-N$이 3.000mg/L 이상 높게 되는 조건에서 고온 메탄 발효는 바람직하지 않는 결과를 나타내게 된다.

• 펄프종이기술
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• 제46권1호
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• pp.18-28
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• 2014

Renewable Portfolio Standards(RPS) is a regulation that requires a renewable energy generated from eco-friendly energy sources such as biomass, wind, solar, and geothermal. The RPS mechanism generally is an obligatory policy that places on electricity supply companies to produce a designated fraction of their electricity from renewable energies. The domestic companies to supply electricity largely rely on wood pellets in order to implement the RPS in spite of undesirable situation of lack of wood resources in Korea. This means that the electricity supply companies in Korea must explore new biomass as an alternative to wood. Palm kernel shell (PKS) and empty fruit bunch (EFB) as oil palm wastes can be used as raw materials used for making pellets after their thermochemical treatment like torrefaction. Torrefaction is a pretreatment process which serves to improve the properties including heating value and energy densification of these oil palm wastes through a mild pyrolysis at temperature typically ranging between 200 and $300^{\circ}C$ in the absence of oxygen under atmospheric pressure. Torrefaction of oil palms wastes at above $200^{\circ}C$ contributed to the increase of fixed carbon with the decrease of volatile matters, leading to the improvement of their calorific values over 20.9 MJ/kg (=5,000 kcal/kg) up to 25.1 MJ/kg (=6,000 kcal/kg). In particular, EFB sensitively responded to torrefaction because of its physical properties like fiber bundles, compared to PKS and hardwood chips. In conclusion, torrefaction treatment of PKS and EFB can greatly contribute to the implement of RPS of the electricity supply companies in Korea through the increased co-firing biomass with coal.

• 한국환경과학회지
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• 제27권4호
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• pp.241-250
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• 2018

The objective of this study was to estimate air quality trends in the study area by surveying monthly and seasonal concentration trends. To do this, the mass concentration of $PM_{10}$ samples and the metals, ions, and total carbon in the $PM_{10}$ were analyzed. The mean concentration of $PM_{10}$ was $33.9{\mu}g/m^3$. The composition of $PM_{10}$ was 39.2% ionic species, 5.1% metallic species, and 26.6% carbonic species (EC and OC). Ionic species, especially sulfate, ammonium, and nitrate, were the most abundant in the $PM_{10}$ and had a high correlation coefficient with $PM_{10}$. Seasonal variation of $PM_{10}$ showed a similar pattern to those of ionic and metallic species. with high concentration during the winter and spring seasons. $PM_{10}$ showed high correlation with the ionic species $NO_3{^-}$ and $NH_4{^+}$. In addition, $NH_4{^+}$ was highly correlated with $SO{_4}^{2-}$ and $NO_3{^-}$. We obtained four factors through factor analysis and determined the pollution sources using the United States Environmental Protection Agency(U.S. EPA) pollution profile. The first factor accounted for 51.1% of $PM_{10}$ from complex sources, that is, soil, motor vehicles, and secondary particles: the second factor indicated marine sources; the third factor, industry-related sources; and the last factor, heating-related sources. However, the pollution profile used in this study may be somewhat different from the actual situation in Korea because it was from US EPA. Therefore, to more accurately estimate the pollutants present, it is necessary to create a pollution profile for Korea.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• 제25권1호
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• pp.57-81
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• 1997

Numerical prediction of nocturnal thermal high in summer of the 1995 near Taegu city located in a basin has been carried out by a non-hydrostatic numerical model over complex terrain through one-way double nesting technique in the Z following coordinate system. Under the prevailing westerly winds, vertical turbulent fluxes of momentum and heat over mountains for daytime hours are quite strong with a large magnitude of more than $120W/\textrm{m}^2$, but a small one of $5W/\textrm{m}^2$ at the surface of the basin. Convective boundary layer (CBL) is developed with a thickness of about 600m over the ground in the lee side of Mt. Hyungje, and extends to the edge of inland at the interface of land sea in the east. Sensible heat flux near the surface of the top of the mountain is $50W/\textrm{m}^2$, but its flux in the basin is almost zero. Convergence of sensible heat flux occurs from the ground surface toward the atmosphere in the lower layer, causing the layer over the mountain to be warmed up, but no convergance of the flux over the basin results from the significant mixing of air within the CBL. As horizontal transport of sensible heat flux from the top of the mountain toward over the basin results in the continuous accumulation of heat with time, enhancing air temperature at the surface of the basin, especially Taegu city to be higher than $39.3^{\circ}C$. Since latent heat fluxes are $270W/\textrm{m}^2$ near the top of the mountain and $300W/\textrm{m}^2$ along the slope of the mountain and the basin, evaporation of water vapor from the surface of the basin is much higher than one from the mountain and then, horizontal transport of latent heat flux is from the basin toward the mountain, showing relative humidity of 65 to 75% over the mountain to be much greater than 50% to 55% in the basin. At night, sensible heat fluxes have negative values of $-120W/\textrm{m}^2$ along the slope near the top of the mountain and $-50W/\textrm{m}^2$ at the surface of the basin, which indicate gain of heat from the lower atmosphere. Nighttime radiative cooling produces a shallow nocturnal surface inversion layer with a thickness of about 100m, which is much lower than common surface inversion layer, and lifts extremely heated air masses for daytime hours, namely, a warm pool of $34^{\circ}C$ to be isolated over the ground surface in the basin. As heat transfer from the warm pool in the lower atmosphere toward the ground of the basin occurs, the air near the surface of the basin does not much cool down, resulting in the persistence of high temperature at night, called nocturnal thermal high or tropical night. High relative humidity of 75% is found at the surface of the basin under the moderate wind, while slightly low relative humidity of 60% is along the eastern slope of the high mountain, due to adiabatic heating by the srong downslope wind. Air temperature near the surface of the basin with high moisture in the evening does not get lower than that during the day and the high temperature produces nocturnal warming situation.

• 생물환경조절학회지
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• 제29권3호
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• pp.285-292
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• 2020

본 연구에서는 CFD 시뮬레이션 기법을 이용하여 유리온실의 내부 환경 변화를 예측하는 모델을 개발하였으며, 실험을 통해 확보한 데이터를 이용하여 이를 검증하였다. 주·야간 실험 데이터를 경계조건으로 하는 Case 1, 2, 3의 시뮬레이션 예측값은 실험값 대비 평균 2.62℃ 높게 나타났으며, 최대편차와 균일도는 각각 평균 1.12℃, 2.92%p 높게 나타났다. Case 1에서 Case 3으로 외기온도가 변화함에 따라 조성되는 온실 내부 온도는 평균 0.84℃의 차이를 보였으며, R²는 0.9628로 실험값과 시뮬레이션 예측값 간 유사한 경향을 보임을 확인하였다. 시뮬레이션 예측 결과 해석대상 온실 내 불균일한 온도분포를 확인하였다. 해석대상 온실의 효율적인 열에너지 관리를 위해 온실 내 방열관과 FCU의 위치 변경, 온실 구조 변경 등이 필요하다고 판단되었다. 추후 현장에서의 적용을 위해 정밀한 분석이 필요하며 이를 위해 온실 내부 작물 및 구조물 미고려, 온실을 완전 밀폐로 가정하는 등 모델 정립을 위한 조건들에 의한 열전달 현상을 고려한 모델의 개선이 필요하다고 판단된다.

• 한국환경과학회지
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• 제28권4호
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• pp.413-422
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• 2019

The objective of this study was to estimate the trends of air quality in the study area by analyzing monthly and seasonal concentration trends obtained from sampled data. To this aim, the mass concentrations of $PM_{2.5}$ in the air were analyzed, as well as those of metals, ions, and total carbon within the $PM_{2.5}$. The mean concentration of $PM_{2.5}$ was $22.7{\mu}g/m^3$. The mass composition of $PM_{2.5}$ was as follows: 31.1% of ionic species, 2.2% of metallic species, and 26.7% of carbonic species (EC and OC). Ionic species, especially sulfate, ammonium, and nitrate, were the most abundant in the $PM_{2.5}$ and exhibited a high correlation coefficient with the mass concentration of $PM_{2.5}$. Seasonal variations of $PM_{2.5}$ showed a similar pattern to those of ionic and metallic species, with high concentrations during winter and spring. $PM_{2.5}$ also had a high correlation with the ionic species $NO_3{^-}$ and $NH_4{^+}$. In addition, $NH_4{^+}$ was highly correlated with $NO_3{^-}$. Through factor analysis, we identified four controlling factors, and determined the pollution sources using the United States Environmental Protection Agency(U.S. EPA) pollution profile. The first factor, accounting for 19.1% of $PM_{2.5}$ was attributed to motor vehicles and heating-related sources: the second factor indicated industry-related sources and secondary particles, and the other factors indicated soil, industry-related and marine sources. However, the pollution profile used in this study may be somewhat different from the actual situation in Korea, since it was obtained from US EPA. Therefore, to more accurately estimate the pollutants present in the air, a pollution profile for Korea should be produced.