• Title/Summary/Keyword: School ground

Search Result 2,415, Processing Time 0.041 seconds

Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2014 (설비공학 분야의 최근 연구 동향: 2014년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.27 no.7
    • /
    • pp.380-394
    • /
    • 2015
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2014. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of heat and mass transfer, cooling and heating, and air-conditioning, the flow inside building rooms, and smoke control on fire. Research issues dealing with duct and pipe were reduced, but flows inside building rooms, and smoke controls were newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for thermal contact resistance measurement of metal interface, a fan coil with an oval-type heat exchanger, fouling characteristics of plate heat exchangers, effect of rib pitch in a two wall divergent channel, semi-empirical analysis in vertical mesoscale tubes, an integrated drying machine, microscale surface wrinkles, brazed plate heat exchangers, numerical analysis in printed circuit heat exchanger. In the area of pool boiling and condensing, non-uniform air flow, PCM applied thermal storage wall system, a new wavy cylindrical shape capsule, and HFC32/HFC152a mixtures on enhanced tubes, were actively studied. In the area of industrial heat exchangers, researches on solar water storage tank, effective design on the inserting part of refrigerator door gasket, impact of different boundary conditions in generating g-function, various construction of SCW type ground heat exchanger and a heat pump for closed cooling water heat recovery were performed. (3) In the field of refrigeration, various studies were carried out in the categories of refrigeration cycle, alternative refrigeration and modelling and controls including energy recoveries from industrial boilers and vehicles, improvement of dehumidification systems, novel defrost systems, fault diagnosis and optimum controls for heat pump systems. It is particularly notable that a substantial number of studies were dedicated for the development of air-conditioning and power recovery systems for electric vehicles in this year. (4) In building mechanical system research fields, seventeen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the evaluation of work noise in tunnel construction and the simulation and development of a light-shelf system. The subjects of building energy were worked on the energy saving of office building applied with window blind and phase change material(PCM), a method of existing building energy simulation using energy audit data, the estimation of thermal consumption unit of apartment building and its case studies, dynamic window performance, a writing method of energy consumption report and energy estimation of apartment building using district heating system. The remained studies were related to the improvement of architectural engineering education system for plant engineering industry, estimating cooling and heating degree days for variable base temperature, a prediction method of underground temperature, the comfort control algorithm of car air conditioner, the smoke control performance evaluation of high-rise building, evaluation of thermal energy systems of bio safety laboratory and a development of measuring device of solar heat gain coefficient of fenestration system.

Recent Progress in Air Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2007 (설비공학 분야의 최근 연구 동향 : 2007년 학회지 논문에 대한 종합적 고찰)

  • Han, Hwa-Taik;Shin, Dong-Sin;Choi, Chang-Ho;Lee, Dae-Young;Kim, Seo-Young;Kwon, Yong-Il
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.20 no.12
    • /
    • pp.844-861
    • /
    • 2008
  • The papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during the year of 2007 have been reviewed. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environments. The conclusions are as follows. (1) The research trends of fluid engineering have been surveyed as groups of general fluid flow, fluid machinery and piping, etc. New research topics include micro nano fluid, micropump and fuel cell. Traditional CFD was still popular and widely used in research and development. Studies about fans and pumps were performed in the field of fluid machinery. Characteristics of flow and fin shape optimization are studied in the field of piping system. (2) The research works on heat transfer have been reviewed in the field of heat transfer characteristics, heat exchangers, and desiccant cooling systems. The research on heat transfer characteristics includes thermal transport in pulse tubes, high temperature superconductors, ground heat exchangers, fuel cell stacks and ice slurry systems. For the heat 'exchangers, the research on pin-tube heat exchanger, plate heat exchanger, condensers and gas coolers has been cordially implemented. The research works on heat transfer augmenting tubes have been also reported. For the desiccant cooling systems, the studies on the design and operating conditions for desiccant rotors as well as performance index are noticeable. (3) In the field of refrigeration, many papers were presented on the air conditioning system using CO2 as a refrigerant. The issues on the two-stage compression, the oil selection, and the appropriate oil charge were treated. The subjects of alternative refrigerants were also studied steadily. Hydrocarbons, DME and their mixtures were considered and various heat transfer correlations were proposed. (4) Research papers have been reviewed in the field of building facilities by grouping into the researches on heat and cold sources, air conditioning and air cleaning, ventilation and fire research including tunnel ventilation, flow control of piping system, and sound research with drain system. Main focuses have been addressed to the promotion of efficient or effective use of energy, which helps to save energy and results in reduced environmental pollution and operating cost. (5) Studies were mostly focused on analyzing the indoor environment in various spaces like cars, old tombs, machine rooms, and etc. in an architectural environmental field. Moreover, subjects of various fields such as the evaluation of noise, thermal environment, indoor air quality and development of energy analysis program were researched by various methods of survey, simulation, and field experiment.

The Effect on the Forest Temperature by Reduced Biomass Caused by Natural Forest Thinning (천연림 간벌에 기인한 산림생물량 감소가 산림 내부 온도에 미치는 영향 연구)

  • Kang, Rae-Yeol;Hong, Suk-Hwan
    • Korean Journal of Environment and Ecology
    • /
    • v.32 no.3
    • /
    • pp.303-312
    • /
    • 2018
  • This study was conducted to investigate the relationship between the decrease of forest biomass by forest thinning and the change of temperature in the natural forest by measuring forest biomass and temperature before and after forest thinning in the Pusan National University forest where afforestation had been carried out. We intended to investigate the relationship between the forest biomass, estimated by calculating the Basal area, Crown area and Crown volume using the same formula to the same quadrat before and after forest thinning, and the forest temperature. Temperature measurement was carried out on April 20, 2016 through 28 before forest thinning, July 26, 2016 through November 4 around the time of forest thinning, and April 15, 2017 through May 8 after forest thinning. A temperature data logger was installed to point north at the height of 2.0 m above the ground in the center of the quadrat to record data every 10 minutes during the measurement periods. We used the AWS (Automatic Weather Station) data of the Dongnae-gu area located in the nearby city because it was difficult to set the control group since the whole forest was the subject to the forest thinning. The analysis of the relationship between forest biomass change and temperature showed that the change in temperature inside the forest was the greatest in the midday (12:00 - 15: 00) and was highly correlated with the Crown volume in the forest biomass. The temperature increase was much larger (average $1.91^{\circ}C$) 1 year after forest thinning than immediately after forest thinning (average $0.74^{\circ}C$). The comparison of the decrease rate of Crown volume and the increase in temperature showed that the Pitch pine community, which showed the highest decrease of Crown volume by 15.4%, recorded the highest temperature rise of $1.06^{\circ}C$ immediately after forest thinning and $2.49^{\circ}C$ 1 year after forest thinning. The Pitch pine-Korean red pine community, which showed the lowest Crown volume reduction rates with 5.0%, recorded no significant difference immediately after forest thinning but a temperature rise of $0.92^{\circ}C$ 1 year after forest thinning. The results confirmed that the decrease of forest biomass caused by forest thinning led to a rapid increase of the internal temperature. The fact that the temperature increase was more severe after 1 year than immediately after forest thinning confirmed that the microclimate changes due to the removed biomass cannot be recovered in a short time.

Falls among Community Dwelling Elderly People: Prevalence and Associated Factors (일부 농촌지역 노인들의 낙상발생과 관련된 요인)

  • Cho, Young-Chae;Yoon, Hyun-Suk
    • Journal of agricultural medicine and community health
    • /
    • v.29 no.2
    • /
    • pp.223-235
    • /
    • 2004
  • Objectives: This study was to evaluate the actual condition of falls among community-dwelling elderly people and its related factors to prepare for the establishment of comprehensive prevention programs of senior population. Methods: The study subjects included 460 home residents over 65 years in a district of Chungnam Province and interviews were given to all of them, asking about experiences of falls and their related factors. The analysis of study results came to the following conclusions. Results: The rate of falls among total subjects was 35.5%. With the percentage by age and sex, over 70's and female were significantly higher than male(p=0.000) and under 69 (p=0.008). The groups with poor visual acuity and hearing ability had higher rate of falls than the normal groups based on their health status. In terms of place they experienced falls, out-door occurrence accounted for 53.4% of total falls, which was higher 46.6% of in-door. By season when falls are experienced, "winter" showed the greatest rate, and by time of the day, evening had the highest rate. By causes of falls, "Slippery ground"accounted for 30.5% and "Tumbled over" 23.5% of total falls, respectively, showing the major role of environmental causes for falls. For individual factors, "Irritability" and "Carelessness" occupied 11.3%, 10.8% of total falls, respectively. The Odds Ratios for falls in women was 2.19 times higher than in men, and those in 70's are 2.01 times higher than in 60's, and those with abnormal BMI was 3.68 times higher than in normal groups, and those with perceived symptoms was 1.94 times higher than those without. Conclusions: It is suggested that more consideration should be directed toward taking comprehensive and systematic prevention measures ranging from setting-up the injury-protective environments to allowing senior citizens to have competence in ADL activity as well as proper general health conditions, considering the higher rate of falls for elderly persons in a rural part of this country than that of western countries and the greater proportion of falls which can be ascribed to environmental factors.

  • PDF

A MEASUREMENT OF THE COSMIC MICROWAVE BACKGROUND B-MODE POLARIZATION WITH POLARBEAR

  • ADE, P.A.R.;AKIBA, Y.;ANTHONY, A.E.;ARNOLD, K.;ATLAS, M.;BARRON, D.;BOETTGER, D.;BORRILL, J.;CHAPMAN, S.;CHINONE, Y.;DOBBS, M.;ELLEFLOT, T.;ERRARD, J.;FABBIAN, G.;FENG, C.;FLANIGAN, D.;GILBERT, A.;GRAINGER, W.;HALVERSON, N.W.;HASEGAWA, M.;HATTORI, K.;HAZUMI, M.;HOLZAPFEL, W.L.;HORI, Y.;HOWARD, J.;HYLAND, P.;INOUE, Y.;JAEHNIG, G.C.;JAFFE, A.H.;KEATING, B.;KERMISH, Z.;KESKITALO, R.;KISNER, T.;JEUNE, M. LE;LEE, A.T.;LEITCH, E.M.;LINDER, E.;LUNGU, M.;MATSUDA, F.;MATSUMURA, T.;MENG, X.;MILLER, N.J.;MORII, H.;MOYERMAN, S.;MYERS, M.J.;NAVAROLI, M.;NISHINO, H.;ORLANDO, A.;PAAR, H.;PELOTON, J.;POLETTI, D.;QUEALY, E.;REBEIZ, G.
    • Publications of The Korean Astronomical Society
    • /
    • v.30 no.2
    • /
    • pp.625-628
    • /
    • 2015
  • POLARBEAR is a ground-based experiment located in the Atacama desert of northern Chile. The experiment is designed to measure the Cosmic Microwave Background B-mode polarization at several arcminute resolution. The CMB B-mode polarization on degree angular scales is a unique signature of primordial gravitational waves from cosmic inflation and B-mode signal on sub-degree scales is induced by the gravitational lensing from large-scale structure. Science observations began in early 2012 with an array of 1.274 polarization sensitive antenna-couple Transition Edge Sensor (TES) bolometers at 150 GHz. We published the first CMB-only measurement of the B-mode polarization on sub-degree scales induced by gravitational lensing in December 2013 followed by the first measurement of the B-mode power spectrum on those scales in March 2014. In this proceedings, we review the physics of CMB B-modes and then describe the Polarbear experiment, observations, and recent results.

Process development of a virally-safe dental xenograft material from porcine bones (바이러스 안전성이 보증된 돼지유래 골 이식재 제조 공정 개발)

  • Kim, Dong-Myong;Kang, Ho-Chang;Cha, Hyung-Joon;Bae, Jung Eun;Kim, In Seop
    • Korean Journal of Microbiology
    • /
    • v.52 no.2
    • /
    • pp.140-147
    • /
    • 2016
  • A process for manufacturing virally-safe porcine bone hydroxyapatite (HA) has been developed to serve as advanced xenograft material for dental applications. Porcine bone pieces were defatted with successive treatments of 30% hydrogen peroxide and 80% ethyl alcohol. The defatted porcine bone pieces were heat-treated in an oxygen atmosphere box furnace at $1,300^{\circ}C$ to remove collagen and organic compounds. The bone pieces were ground with a grinder and then the bone powder was sterilized by gamma irradiation. Morphological characteristics such as SEM (Scanning Electron Microscopy) and TEM (Transmission Electron Microscopy) images of the resulting porcine bone HA (THE Graft$^{(R)}$) were similar to those of a commercial bovine bone HA (Bio-Oss$^{(R)}$). In order to evaluate the efficacy of $1,300^{\circ}C$ heat treatment and gamma irradiation at a dose of 25 kGy for the inactivation of porcine viruses during the manufacture of porcine bone HA, a variety of experimental porcine viruses including transmissible gastroenteritis virus (TGEV), pseudorabies virus (PRV), porcine rotavirus (PRoV), and porcine parvovirus (PPV) were chosen. TGEV, PRV, PRoV, and PPV were completely inactivated to undetectable levels during the $1,300^{\circ}C$ heat treatment. The mean log reduction factors achieved were $${\geq_-}4.65$$ for TGEV, $${\geq_-}5.81$$ for PRV, $${\geq_-}6.28$$ for PRoV, and $${\geq_-}5.21$$ for PPV. Gamma irradiation was also very effective at inactivating the viruses. TGEV, PRV, PRoV, and PPV were completely inactivated to undetectable levels during the gamma irradiation. The mean log reduction factors achieved were $${\geq_-}4.65$$ for TGEV, $${\geq_-}5.87$$ for PRV, $${\geq_-}6.05$$ for PRoV, and $${\geq_-}4.89$$ for PPV. The cumulative log reduction factors achieved using the two different virus inactivation processes were $${\geq_-}9.30$$ for TGEV, $${\geq_-}11.68$$ for PRV, $${\geq_-}12.33$$ for PRoV, and $${\geq_-}10.10$$ for PPV. These results indicate that the manufacturing process for porcine bone HA from porcine-bone material has sufficient virus-reducing capacity to achieve a high margin of virus safety.

A Study of the Planning Process, Design Idea and Implementation of the Gwanghwamun Plaza (광화문광장 조성과정 및 설계 연구)

  • Shin, Hyun-Don;Zoh, Kyung-Jin
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.41 no.4
    • /
    • pp.24-41
    • /
    • 2013
  • This study aims to investigate the complex planning processes and design ideas of the Gwanghwamun Plaza which was opened in 2009. The opening of the plaza was significant as it was built in order to restore the symbolic meaning of axis in the historical Joseon Dynasty that was distorted during the Japanese Imperialism. The plaza itself attracts many citizens and tourists by providing the empty ground carrying historical ambiences around. In this paper, the story of the Gwanghwamun plaza will be summarized. Particularly, the background of promoting the project will be discussed and the whole planning process will be dealt with. The plaza was realized through several stages. First, the planning stage will be reviewed. The planning stage had been a quite long process since the initial idea was discussed. Since the early 90s, the political decision of making the plaza was made through the change of people's understanding toward public space. At this stage, the city government worked together with diverse citizens and professionals to share the vision and to realize the right decision in making the plaza. Second, the design stage will be elaborated in detail. This is the second design stage. The former was the idea competition and the latter was the turn-key base. The final design scheme emphasized the restoration of symbolic axis and the forgotten Yukjo Street. The scheme consists of four zones such as history restoration zone, prospect and history representation zone, culture zone, and the urban zone. Through the whole design process, the original idea remained as it was. The design concept was "a place of memory and prospect." It emphasizes the history representation, view corridor, cultural activities platform as well as the emptiness and flexibility of the basic premise of the plaza. Finally, the construction stage will be discussed. There were some additions and omissions in the construction process. The design chances in the construction stage will be reviewed in detail. After the opening of the plaza, there were some changes in the detail design. We will discuss how and why these modifications were made. In the end, the social and cultural implication of the plaza will be discussed. The storytelling of the Gwanghwamun Plaza will contribute to the clear understanding of planning and design process of pubic places. Based on this reflection, we are able to think about some suggestions of public projects for the future.

Water Landscape Displaying Techinques of Traditional Gardens between China and Korea - With Soswaewon and ZhuozhengYuan - (한.중 전통원림의 수경관 연출기법 비교 연구 - 소쇄원과 졸정원을 중심으로 -)

  • Lee, Hang Lyoul;Kim, Sun Rye
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.30 no.4
    • /
    • pp.1-13
    • /
    • 2012
  • Landscape Garden tradition of excellent examples of places that are focused on hydroponics management. South Korea and China, this thing was noticeable among them South Korea which emphasizes the natural contours of the natural streams in accordance with the basic idea to use examples that feature will do. Gardens in China by constructing a flat terrain also naturally expect to find examples of conscious ideas depending on the water and the mountains are characterized. These differences and similarities through the Gardens of the tradition of separating the two countries to build their Garden by site Soswaewon and Zolzengwon appear in the target hand is to identify the characteristics between the director. Research methods literature survey, field survey of the natural environment through the plantation, background history, the people who intend to study, to configure the ground water space, Jian, construction and management has been studied in hydroponics. As a result, Damyang-gun, Jeollanam-do, South Korea in the Garden of the Soswaewon(瀟灑園) organization with inner garden and outer garden of a small, but the scale of production to Yang San-Bo's 'eunilgwan' implement security based rock mooring takes the form of a linear channel and the water came down from riding pending to avoid artifacts gathered again took the form of streams flowing into that. Hutton was a rubble pile structure Jian. Building an Gwangpunggak, Jewoldang, as Daebongdae consist, respectively, depending on the purpose of the mooring was deployed by focusing. The other hand, is located at Suzhou, Jiangsu of China Zolzengwon(拙政園) flat terrain is located on. Largely divided eastern gardens, Central Gardens and the Gardens of the West was conducted by five thirds of the total area of Water accounted for. Pavilion the center of the pond, Seokgasan achieve a variety of landscapes and architectural features that are most of the Ming. The two countries, each region's natural environment and human environment, different, unique characteristics to each other in the implementation of a unique hydroponic Garden tube and ideological backgrounds, but especially the 'eunilgwan' and the terrain that is divided according to the conditions of this study, so fulfilling Garden was conducted.

A Study on How Reading Comic Books Affects Creativity (만화 읽기가 창의력 향상에 미치는 연구)

  • Jang, Jin-Young;Park, Hye-Ri
    • Cartoon and Animation Studies
    • /
    • s.36
    • /
    • pp.437-467
    • /
    • 2014
  • This study is intended to reveal reading comic books helps improve creativity. Though the long-lasting negative recognition towards comic books has positively changed these days, we need a ground upon which the social recognition needs improvement in that children's comic books have been used as a learning tool. Its introduction points out that there has been shortage of empirical researches on comic book reading, and as one of the empirical research methods, presents a method of comparative analysis on comic book reading, school study, and creativity tests via survey. The theoretical background in the 2nd chapter, first, puts emphasis on the significance of the creativity theory among all the other theories related to creativity, which focuses on problem-solving capacity. Second, it theoretically reviews the meaning which 'fun' and 'interest' have in development of creativity in the context of developmental process of the modern educational theories. Third, it empathizes that traits of reading comic books start off with 'fun' and 'interest', that awareness of reality gets expanded via the process of characters making their way through a strange world with empathy and absorption, and that comic book reading has to do with creativity. Fourth, it presents a model questionnaire with which to study relationship between comic books and creativity in an empirical way. The analysis on the survey outcome in the 3rd chapter shows, first, that smart students read many comic books, not to mention that studying helps improve creativity, which indicates above all, comic book reading and improvement of creativity are not negatively related, but are mutually complementary. Second, that creativity enhanced by reading comic books is higher than that enhanced by studying, which may mean comic book reading is more effective than studying in developing creativity. It has drawn a conclusion based upon these results, that reading comic books bears positive efficacy on both studying and developing creativity. Standing on this conclusion, it proposes it necessary to develop methods by grades of educating how to read comic books and to provide a recommended list of comic books to read.

Radon concentration measurement at general house in Pusan area (부산지역 일반주택에서의 라돈농도측정)

  • Im, In-Cheol
    • Journal of radiological science and technology
    • /
    • v.27 no.2
    • /
    • pp.29-33
    • /
    • 2004
  • Until early 1980s we have lived without thinking that radon ruins our health. But, scientists knew truth that radon radioactive danger is bedeviling on indoor that we live for a long time. Specially, interest about effect that get in danger and injury for Radon and human body is inactive in our country. Recently, with awareness for Radon contamination, We inform about importance and danger of Radon in some station of the Seoul subway, indoor air of school facilities and We had interest with measure and manages. Usually, Radon gas emitted in base of building enters into indoor through building floor split windage back among radon or indoor air of radon daughter nucleus contamination is increased. Therefore, indoor radon concentration rises as there are a lot of windages between number pipe of top and bottom and base that enter crack from estrangement of the done building floor, underground to indoor. Thus, Radon enters into indoor through architecture resources water as well as, kitchen natural gas for choice etc., but more than about 85% from earth's crust emit. Danger and injury of health by Radon and Radon daughter nucleus that is indicated for cause of lung cancer incerases content of uranium of soil rises specially from inside pit of High area and a mine, cave, hermetical space with house. Safe sub-officer of radon concentration can not know and danger always exists large or small during. So, Important thing reduces danger of lung cancer by lowering concentration of Radon within house and building. Therefore, is thought that need general house Radon concentration measurement, measured Radon concentration monthly using Sintillator radon monitor. Study finding appeared high all underground market 1 year than the ground, and the winter appeared high than the summer. Specially, month that pass over 4pCi in house that United States Environmental Protection Agency advises appeared in underground, and appeared and know Radon exposure gravity by 4 months during 12 months. Therefore, Thinking that establishment and regulation of norm and preparation of reduction countermeasure about Radon are pressing feels, and inform result that measure Radon concentration.

  • PDF