• Title/Summary/Keyword: hot environment

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A Study on the Technology Acceptance Factors of the Public Cloud Computing Services (공공 클라우드 컴퓨팅 서비스의 기술수용 결정요인 연구)

  • Kim, Dae Ho;Kim, Tae Hyung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.8 no.2
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    • pp.93-106
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    • 2013
  • Cloud computing services have became an hot issues in business fields while the IT-related global company such as Amazon, MS, and Google took part in. The cloud computing makes it possible to share in the form of outsourcing of hardware and software through the Internet, to build a distributed computing environment via multiple terminals, and to reduce the cost using open source. Such a cloud computing services have not shown any significant growth in Korea yet compared to other countries. Therefore, in this study focusing on public cloud computing services, it is intended to analyze the determinants of public cloud computing services using the technology model. Thus, for users using public cloud services, we conducted a questionnaire survey from the beginning of January 2013 to the end of February 2013. And we derived a research model based on the Technology Acceptance Model(TAM). As a result of this study, it shows that personal aspects significantly impacts on the perceived usability, service aspects, systems aspects, and the intent of the technology acceptances. System aspects significantly effect on the intent of technology acceptances. Perceived usability significantly effects on the service aspects and the systems aspects. The main factors effecting on the intent of the technology acceptances are system aspects and perceived usability in order. And it shows that the personal aspects decreases the intent of the technology acceptances.

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Promotion Directions of Spa Industry Using Local Resources in Jeju Island, Korea (제주도 향토자원을 활용한 스파산업 육성방향)

  • Yoon, Hye Yung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.8 no.1
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    • pp.69-78
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    • 2013
  • Settled lifestyle as important to health and healing to medical tourism and wellness tourism in the 21st century has emerged as the best promising service industry. Jeju Island has a variety of local resources, and the directions was considered to spa industry promotion application it. Jeju Island has a variety of local resources which can be used for spa industry promotion. Jeju Island's beautiful natural environment, mineral resources, water resources, biological resources, agricultural products, traditional folk remedies available in Jeju's spa treatments. Using the local resources of Jeju, 'Jeju specialized spa treatments' can develop of 12 kinds of spa treatments. Namely, thalssotherapy, stone therapy, black sand poultice, hot-floored therapy using volcanic soil, thalassotherapy, drinking therapy, hydrotherapy, herbal/medicinal plants poultice, forest therapy, Spa cuisine, facial beauty, diet therapy. 12 kinds of Jeju specialized spa treatments development and service to the local resources of basic research on the physical and chemical characteristics, product development, clinical trials, efficacy studies should precede. In addition, customized spa services programs should be developed considering the propensity of customers, customer needs, and a spa type. And standardized program of spa services and need a manual painter. Medical tourism and wellness tourism in conjunction with efforts to be considered in order to increase the competitiveness of the spa industry in Jeju.

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Combustion Characteristics of Landfill Gas in Constant Volume Combustion Chamber for Large Displacement Volume Engine (IV) -Torch Ignition (2) - (대형기관 모사 정적연소실에서 매립지 가스의 연소특성에 대한 연구 (IV) -토치 점화 (2)-)

  • Ko, Ansu;Ohm, Inyong;Kwon, Soon Tae
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.2
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    • pp.135-146
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    • 2015
  • This paper is the fourth on the combustion characteristics of the landfill gas in a constant volume combustion chamber for a large displacement volume commercial engine and the second dealing with torch ignition. It discusses the combustion characteristics of torch ignition on the basis of the heat release and visualization. The results show that the jet and/or spout from the torch promote combustion by accelerating the flame front in the main combustion chamber. In addition, a hot gas jet exists when the orifice diameter is 4 mm, whereas the flame passes directly through the orifice if the diameter is 6 mm or greater. In addition, the effect of torch ignition differs according to the combination of the methane fraction, torch volume, and orifice size because various combustion processes occur as a result of the interaction of these parameters. Finally, it was found that the most suitable torch should have an orifice diameter of not less than 6 mm and an area ratio of not more than 0.15 to secure a consistent combustion process in a real engine.

Growth Temperature-Dependent Conversion of De novo-Synthesized Unsaturated Fatty Acids into Polyhydroxyalkanoic Acid and Membrane Cyclopropane Fatty Acids in the Psychrotrophic Bacterium Pseudomonas fluorescens BM07

  • LEE , HO-JOO;RHO, JONG-KOOK;YOON, SUNG-CHUL
    • Journal of Microbiology and Biotechnology
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    • v.14 no.6
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    • pp.1217-1226
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    • 2004
  • A psychrotrophic bacterial strain, Pseudomonas fluorescens BM07, synthesized unsaturated fatty acids (UFA) from fructose in response to lowering of growth temperature, and incorporated them into both polyhydroxyalkanoic acid (PHA) and membrane lipid. The blocking of PHA synthesis by adding 5 mM 2-bromooctanoic acid to the growth medium, containing 70 mM fructose, was found to be a useful means to profile the composition of membrane lipid by gas chromatography. As the growth temperature changed from 35 to $50^{\circ}C$, the total content of two UFA, 3-hydroxy-cis-5­dodecenoic acid ($C_{12:1}$) and 3-hydroxy-cis-7-tetradecenoic acid ($C_{14:1}$), in PHA increased from 31 to 44 $mol\%$. The growth at lower temperatures also led to an increase in the level of two major UFA, palmitoleic acid (C16:1 cis9) and cis-vaccenic acid (C18:1 cis11), in membrane lipid. A fraction of these membrane-lipid UFA was converted to their corresponding cyclopropane fatty acids (CFA). The CFA conversion was a function of culture time, exhibiting biphasic increase before and after entering the stationary phase. However, pH changes in growth media had no effect on the CFA conversion, which is contrary to the case of E. coli reported. The cells grown at $30^{\circ}C$ responded to a cold shock (lowering the medium temperature down to $10^{\circ}C$) by increasing the level of C16:1 cis9 and C 18: I cis II up to that of $10^{\circ}C$-grown control cells and concomitantly decreasing the relative level of cis-9,10­methylenehexadecanoic acid (the CFA converted from C16:1 cis9) from 14 to 8 $mol\%$, whereas the 10-grown cells exhibited little change in the lipid composition when exposed to a warmer environment of $30^{\circ}C$ for 12 h. Based on this one- way response, we suggest that this psychrotrophic strain responds more efficiently and sensitively to a cold shock than to a hot shock. It is also suggested that BM07 strain is a good producer of two unsaturated 3-hydroxyacids, $C_{12:1}\;and\;C_{141:1}$.

Effect of γ-Aminobutyric Acid-producing Lactobacillus Strain on Laying Performance, Egg Quality and Serum Enzyme Activity in Hy-Line Brown Hens under Heat Stress

  • Zhu, Y.Z.;Cheng, J.L.;Ren, M.;Yin, L.;Piao, X.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.7
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    • pp.1006-1013
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    • 2015
  • Heat-stress remains a costly issue for animal production, especially for poultry as they lack sweat glands, and alleviating heat-stress is necessary for ensuring animal production in hot environment. A high ${\gamma}$-aminobutyric acid (GABA)-producer Lactobacillus strain was used to investigate the effect of dietary GABA-producer on laying performance and egg quality in heat-stressed Hy-line brown hens. Hy-Line brown hens (n = 1,164) at 280 days of age were randomly divided into 4 groups based on the amount of freeze-dried GABA-producer added to the basal diet as follows: i) 0 mg/kg, ii) 25 mg/kg, iii) 50 mg/kg, and iv) 100 mg/kg. All hens were subjected to heat-stress treatment through maintaining the temperature and the relative humidity at $28.83{\pm}3.85^{\circ}C$ and 37% to 53.9%, respectively. During the experiment, laying rate, egg weight and feed intake of hens were recorded daily. At the 30th and 60th day after the start of the experiment, biochemical parameters, enzyme activity and immune activity in serum were measured. Egg production, average egg weight, average daily feed intake, feed conversion ratio and percentage of speckled egg, soft shell egg and misshaped egg were significantly improved (p<0.05) by the increasing supplementation of the dietary GABA-producer. Shape index, eggshell thickness, strength and weight were increased linearly with increasing GABA-producer supplementation. The level of calcium, phosphorus, glucose, total protein and albumin in serum of the hens fed GABA-producing strain supplemented diet was significantly higher (p<0.05) than that of the hens fed the basal diet, whereas cholesterol level was decreased. Compared with the basal diet, GABA-producer strain supplementation increased serum level of glutathione peroxidase (p = 0.009) and superoxide dismutase. In conclusion, GABA-producer played an important role in alleviating heat-stress, the isolated GABA-producer strain might be a potential natural and safe probiotic to use to improve laying performance and egg quality in heat-stressed hens.

A thermal-flow analysis of deaerator floor of power plant for reducing the radiative heat transfer effect (발전소 Deaerator floor의 복사효과 저감을 위한 열유동 해석)

  • Kim, Tae-Kwon;Ha, Ji-Soo;Choi, Yong-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.12
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    • pp.476-481
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    • 2016
  • Steam power generation is used to produce electricity through a generator that is connected to a steam turbine. As a result, the surface temperature of the deaerator is $70^{\circ}C$during the summer season, the surface temperature of the storage tank is $67^{\circ}C$, and the air temperature is $50^{\circ}C$. This environment is inappropriate for workers and instruments. Workers adjacent to the deaerator and storage tank in particular feel higher temperatures because of the radiative heat transfer effect. Therefore, we optimized the cooling conditions by computational analysis. Case 1 is the current shape of the power plant, Case 2 has additional insulation, and Case 3 has a radiation shield. Flow is caused by a temperature difference between the heat sources in the wall, and hot air is trapped in the right upper end. Based on the temperature contours and the maximum temperature of the surfaces, Case 2 was found to be the most efficient for reducing radiative heat transfer effects.

Analysis of SWAT Simulated Errors with the Use of MOE Land Cover Data (환경부 토지피복도 사용여부에 따른 예측 SWAT 오류 평가)

  • Heo, Sung-Gu;Kim, Nam-Won;Yoo, Dong-Sun;Kim, Ki-Sung;Lim, Kyoung-Jae
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.194-198
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    • 2008
  • Significant soil erosion and water quality degradation issues are occurring at highland agricultural areas of Kangwon province because of agronomic and topographical specialities of the region. Thus spatial and temporal modeling techniques are often utilized to analyze soil erosion and sediment behaviors at watershed scale. The Soil and Water Assessment Tool (SWAT) model is one of the watershed scale models that have been widely used for these ends in Korea. In most cases, the SWAT users tend to use the readily available input dataset, such as the Ministry of Environment (MOE) land cover data ignoring temporal and spatial changes in land cover. Spatial and temporal resolutions of the MOE land cover data are not good enough to reflect field condition for accurate assesment of soil erosion and sediment behaviors. Especially accelerated soil erosion is occurring from agricultural fields, which is sometimes not possible to identify with low-resolution MOD land cover data. Thus new land cover data is prepared with cadastral map and high spatial resolution images of the Doam-dam watershed. The SWAT model was calibrated and validated with this land cover data. The EI values were 0.79 and 0.85 for streamflow calibration and validation, respectively. The EI were 0.79 and 0.86 for sediment calibration and validation, respectively. These EI values were greater than those with MOE land cover data. With newly prepared land cover dataset for the Doam-dam watershed, the SWAT model better predicts hydrologic and sediment behaviors. The number of HRUs with new land cover data increased by 70.2% compared with that with the MOE land cover, indicating better representation of small-sized agricultural field boundaries. The SWAT estimated annual average sediment yield with the MOE land cover data was 61.8 ton/ha/year for the Doam-dam watershed, while 36.2 ton/ha/year (70.7% difference) of annual sediment yield with new land cover data. Especially the most significant difference in estimated sediment yield was 548.0% for the subwatershed #2 (165.9 ton/ha/year with the MOE land cover data and 25.6 ton/ha/year with new land cover data developed in this study). The results obtained in this study implies that the use of MOE land cover data in SWAT sediment simulation for the Doam-dam watershed could results in 70.7% differences in overall sediment estimation and incorrect identification of sediment hot spot areas (such as subwatershed #2) for effective sediment management. Therefore it is recommended that one needs to carefully validate land cover for the study watershed for accurate hydrologic and sediment simulation with the SWAT model.

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Spatial Pattern and Trend Analysis of Parking-related Electronic Civil Complaints in Jinju-Si (진주시 주차관련 전자민원의 공간패턴분석 및 추이분석)

  • Won, Tae-Hong;Seo, Min-Song;Yoo, Hwan-Hee
    • Journal of Cadastre & Land InformatiX
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    • v.47 no.1
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    • pp.5-14
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    • 2017
  • Korea, which has undergone a rapid urbanization, faces various problems such as the management of facilities, safety, environment and transportation. To solve civil complaints, local governments receive electronic complaints, but complaints are increasing. Therefore, this study conducted the spatial distribution pattern analysis and the trend analysis by presenting location data on spatial information through Geo-coding by collecting electronic civil petition data over the last 10 years targeting Jinju city. Using the ARIMA model, this study predicted the occurrence of complaints over the next two years (2016~2017) through a time series forecast analysis. As a result, the complaints related to illegal parking were the highest, the complaint related to noise was the second highest, and the complaints related to illegal garbage dumping was the third highest. In addition, the analysis of the spatial distribution pattern shows that the largest hot spot was formed in the central commercial district every year. As a result of the time series forecasting analysis for the crackdown of the illegal parking, complaints increased slightly. To compare the predicted value and the actual data showed a similar pattern. It is judged that this study will be utilized to establish effective countermeasures against civil complaints.

Development of a Closed Roof Model for Liquid Manure Storage Tanks to Prevent Corrosion and Atmospheric Diffusion of Oder Gases (부식과 악취가스 대기확산 방지를 위한 액비저장조 밀폐형 지붕모델 개발)

  • Yun, N.K.;Lee, S.H.;Kim, K.W.;Yum, S.H.
    • Journal of Animal Environmental Science
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    • v.14 no.1
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    • pp.61-68
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    • 2008
  • The roof structural model of liquid manure storage tank was designed to improve a structural safety and an ability of resistance to corrosion by the bad environmental condition with high humidity and high gas concentration. Due to corrosion of a general steel, the 5 years used materials were reduced to one-third of a new material in the result of a bending strength test. Some structural materials were tested to evaluate a strength and an anti-corrosion, and stainless steel pipe (STS439), steel angle with zinc hot dipping, rectangular steel pipe covered with FRP (Fiberglass Reinforced Plastics) resin were selected finally. A stainless steel is more expansive about $3{\sim}5$ times than general structural steel. But its durability under heavy corrosive environment is expected twice as long as general steel. The roof models were designed as closed cone type for each of the three structural materials. In the result of a FEM (Finite Element Method) structural analysis for the developed models, the safe snow depth was higher 2.3 times than a general roof structure, when elements of equal section modulus were used.

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Subjective Responses to Thermal Stress for the Outdoor Performance of Smart Clothes

  • Kwon, JuYoun;Parsons, Ken
    • Journal of the Ergonomics Society of Korea
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    • v.36 no.3
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    • pp.169-181
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    • 2017
  • Objective: The aim of this study was to explore the influence of outdoor weather conditions on subjective responses during physical activity. Background: The largest difference between indoor and outdoor conditions is the existence of the sun. The heat load from the sun has an influence on the heat gain of the human body and the intense degree of solar radiation affected thermal comfort. Method: Thirty eight people were exposed to a range of climatic conditions in the UK. Weather in England does not have extremely hot and cold temperature, and the current study was conducted under warm (summer and autumn) and cool (spring and summer) climates. Measurements of the climate included air temperature, radiant temperature (including solar load), humidity and wind around the subjects. Subjective responses were taken and physiological measurements included internal body temperature, heart rate and sweat loss. Results: This study was conducted under four kinds of environmental conditions and the environmental measurement was performed in September, December, March, and June. The values for sensation, comfort, preference, and pleasantness about four conditions were from 'neutral' to 'warm', from 'not uncomfortable' to 'slightly comfortable', from 'slightly cooler' to 'slightly warmer', and from 'neither pleasant nor unpleasant' and 'slightly unpleasant', respectively. All subjective responses showed differences depending on air temperature and wind speed, and had correlations with air temperature and wind speed (p<0.05). However, subjective responses showed no differences depending on the radiant temperature. The combined effects of environmental parameters were showed on some subjective responses. The combined effects of air temperature and radiant temperature on thermal sensation and pleasantness were significant. The combined effects of metabolic rate with air temperature, wind speed and solar radiation respectively have influences on some subjective responses. In the case of the relationships among subjective responses, thermal sensation had significant correlations with all subjective responses. The largest relationship was shown between preference and thermal sensation but acceptance showed the lowest relationship with the other subjective responses. Conclusion: The ranges of air temperature, radiant temperature, wind speed and solar radiation were $6.7^{\circ}C$ to $24.7^{\circ}C$, $17.9^{\circ}C$ to $56.6^{\circ}C$, $0.84ms^{-1}$ to $2.4ms^{-1}$, and $123Wm^{-2}$ to $876Wm^{-2}$ respectively. Each of air temperature and wind speed had significant relationships with subjective responses. The combined effects of environmental parameters on subjective responses were shown. Each radiant temperature and solar radiation did not show any relationships with subjective responses but the combinations of each radiant temperature and solar radiation with other environmental parameters had influences on subjective responses. The combinations of metabolic rate with air temperature, wind speed and solar radiation respectively have influences on subjective responses although metabolic rate alone hardly made influences on them. There were also significant relationships among subjective responses, and pleasantness generally showed relatively high relationships with comfort, preference, acceptance and satisfaction. Application: Subjective responses might be utilized to predict thermal stress of human and the application products reflecting human subjective responses might apply to the different fields such as fashion technology, wearable devices, and environmental design considering human's response etc.