• Title/Summary/Keyword: residential period

Search Result 428, Processing Time 0.032 seconds

A Study on the Formation of Smoke Layer and the Zone modelling in Compartment Fire (건물화재시 연기층 형성과 영역모델에 관한 연구)

  • 허만성
    • Journal of the Korean Society of Safety
    • /
    • v.12 no.4
    • /
    • pp.70-78
    • /
    • 1997
  • The objective of this research is to study on the upper and lower layer temperature, interface height and pressure in case of carpet, chair, trashcan and wardrobe fires in a residential room by performing the theoretical and experimental studies. The theoretical results of the upper and lower layer temperature, the interface height and the pressure were qualitatively well coincided with the experimental results. The uniformly distributed fire in case of carpet showed that the ignition and the initial growth period were relatively short while the fully developed period was considerably long. The concentrated fires such as the wardrobe showed that the ignitions and the initial growth periods were relatively long. The interface heights were around 1m as the steady state. However, at the time of the maximum temperature, the interface height was lowered to 0.5m from the floor. The pressure variation in the fire room ranged between 0.1mmAq and 0.4mmAq, and the temperature reached the highest while the pressure was maximum.

  • PDF

An Experimental Study on the Formation of Smoke Layer of Compartment Fire (건물화재시 연기층의 형성에 관한 실험적연구)

  • 허만성
    • Journal of the Korean Society of Safety
    • /
    • v.12 no.1
    • /
    • pp.94-100
    • /
    • 1997
  • The objective of this research is to study the formations of smoke layer in case of several furniture fires such as trashcan, carpet, mattress and wardrobe as a fire starter in a residential room by performing the experimental studies. The uniformly distributed fire in case of carpet showed that the ignition and the initial growth period were relatively short while the fully developed period was considerably long. The concentrated fires such as the trashcan, mattress and wardrobe showed that the ignitions and the initial growth periods were relatively long. The descending speed of the interface height was proportioned to the inflammability of the furniture and the spread of the fire. The time required to come down around 1m was within 1-3 minutes. The Interface heights for the furniture fires were around 1m as the steady state. However, at the time of the maximum temperature, the interface height was lowered to 0.25m-0.75m from the floor. The carbon dioxide concentration reached the highest while the oxygen concentration was minimum.

  • PDF

Process Planning for Finishing Works of High-rise Residential Buildings Project (고층 공동주택 마감공사의 공정계획 프로세스)

  • Baek, Tae-Yong
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.18 no.11
    • /
    • pp.110-117
    • /
    • 2017
  • In the construction of high-rise residential buildings in which the finishing works are done repetitively in each housing unit, the construction period and cost can be reduced, while maintaining the quality, if the work process is properly managed in order for the resources to be input continuously. Time management methods such as the Bar Chart, CPM and LOB are not appropriate, due to the difficulties involved in the diagraming of repetitive works and applying them to the project. The Tact method also has difficulties in maintaining a constant work flow and needs significant effort and cooperation from the subcontractors to allocate the resources consistently. Partitioning, base works for finishing, floor mortar plastering and the final finishing work are done sequentially in residential buildings projects, and there are many repetitive activities which differ in terms of the work method, work area and productivity. If these repetitive activities are synchronized or converged toward the last work area, the goal of process management can be achieved effectively. Therefore, a process planning method for the finishing works of residential building projects is proposed, which takes into consideration elements, such as the sequential relation between the activities in each housing unit and classification of repetitive works in terms of their management method, work area and production rate, for the continuous input of resources into the housing units.

The Changes in Obesity Prevalence and Dietary Habits in Korean Adults by Residential Area during the Last 10 Years ― Based on the 4th (2007-2009) and the 7th (2016-2018) Korea National Health and Nutrition Examination Survey Data (최근 10년 간 거주 지역에 따른 한국 성인의 식생활 및 비만 유병률 변화 : 제4기(2007~2009)와 제7기(2016~2018) 국민건강영양조사 자료를 이용하여)

  • Kim, Da-Mee;Kim, Kyung-Hee
    • Korean Journal of Community Nutrition
    • /
    • v.26 no.1
    • /
    • pp.37-47
    • /
    • 2021
  • Objectives: The purpose of this study was to discover the changes in obesity prevalence and dietary habits in Korean adults residing in various residential areas during the last 10 years. Methods: Data on Korean adults aged 19 years and above was obtained from the 4th (2007-2009) and the 7th (2016-2018) Korea National Health and Nutrition Examination Survey. The subjects were classified into metropolitan (4th: n=5,977, 7th: n=6,651), urban (4th: n=4,511, 7th: n=5,512) and rural (4th: n=3,566, 7th: n=2,570) based on their residence. The general characteristics, nutrient intake, intake amount, food groups, and healthy dietary factors were analyzed. The association between residential areas and obesity prevalence were analyzed by multiple logistic regression. Results: In urban and rural areas, the obesity rate increased in the 7th survey compared to the 4th survey, excluding the metropolitan area. The carbohydrate intake decreased, and lipid intake increased in the 7th survey compared to the 4th survey. Over the same period, the intake of cereals and vegetables decreased, and the intake of meat and processed foods increased. Rural residents had a higher intake of cereals and vegetables, and a lower intake of milk and processed foods than those in metropolitan areas and urban residents. The proportion of subjects who practiced a healthy diet increased in the 7th survey compared to the 4th survey. In the 4th survey, there was no relationship seen between the prevalence of obesity and the subject's residential area, but in the 7th survey, the odds ratio of obesity was higher in rural areas than in the metropolitan areas, confirming the regional gap (OR: 1.16, 95% CI=1.00-1.36, P=0.044). Conclusions: This study showed that the obesity prevalence increased in rural residents compared to metropolitan residents, indicating a gap between the regions. The nutrient intake and intake of food groups changed in the 10 years under consideration, and there were differences seen between regions. Therefore, it is necessary to formulate a policy that will reduce obesity prevalence and health inequalities between regions.

Quantification of the CO2 Footprint in Residential Construction

  • Don Mah;Juan D. Manrique;Haitao Yu;Mohamed Al-Hussein;Reza Nasseri
    • International conference on construction engineering and project management
    • /
    • 2009.05a
    • /
    • pp.525-536
    • /
    • 2009
  • The current residential process adheres to a traditional method of construction involving wood framing on-site on poured concrete foundations which has been widely applied in North America. A conventional residential construction process can include seventeen distinct stages ranging from stake-out to pre-occupancy inspection. The current practice possesses short comings including high construction material wastes, long scheduling timelines, adverse weather conditions, poor quality, low efficiencies and negative environmental impacts from transportation and equipment use. Over CAN $5 billion dollars was spent in the construction sector during 2007 in Canada. Previous findings in CO2 emissions during the construction process of a conventional dwelling emphasize more than 45 tonnes of CO2 emissions. Hence, in Alberta alone during 2007, almost 50,000 residential units would release more than two million tonnes of CO2. These numbers demonstrate the economical and environmental impact in building construction and its relationship with CO2 emissions. The aim of this paper is to quantify the CO2 emissions from the current residential construction process in order to establish the baseline for CO2 emission reduction opportunities. The quantification collection methodology will be approached by identifying the seventeen various stages of construction and quantifying the contributions of CO2 from specific activities and their impacts of work for each stage. The approach of separating these into separate stages for collection will allow for independent opportunities for analysis from various independent contractors from the entire scope of work. The use of BIM will be implemented to efficiently quantify CO2 emissions. Based on the CO2 quantification baseline, emission reduction opportunities such as an industrialized construction process will be introduced that allows homebuilders to reduce the environmental and economical impact of home construction while enabling them to produce higher quality, more energy efficient homes in a safer and shorter period of time.

  • PDF

Characteristics of and Affecting Factors on the Concentrations of Polycyclic Aromatic Hydrocarbons Associated with PM10in the Urban Atmosphere (도시 대기 중 PM10에 함유된 다환방향족탄화수소의 농도분포특성과 주요 영향인자)

  • 최진수;백성옥
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.19 no.1
    • /
    • pp.33-44
    • /
    • 2003
  • The atmospheric concentrations of particulate polycyclic aromatic hydrocarbons (PAHs) associated with PM$_{10}$ were determined in Taegu metropolitan area. Sampling was undertaken every five days throughout one year period from 1993 to 1994 at four sites, representing a residential, a commercial, an industrial, and a sub-urban area, respectively. Benzo (e) pyrene, benzo (k) fluoranthene, and chrysene were found to be the most abundant com-pounds during the study period. The concentrations of benzo (a) pyrene, one of carcinogenic PAHs, ranged 2.0~4.8 ng/㎥ in winter and 0.5~1.5 ng/㎥ in summer season, indicating a marked seasonal variation. It was found that there were very similar patterns in the relative profiles of PM$_{10}$-bound PAH concentrations among the four sampling sites, while the absolute levels of each PAH were significantly different from each site. In addition, the patterns of summer to winter concentration ratios for each PAH were almost identical between the different sites. Despite difficulties due to the lack of good markers for specific sources in the target compounds, we were able to evaluate and describe the effects of vehicle emissions and space heatings, using relative profiles of PAHs, winter to summer (W/S) ratios, PAH-to-PAH ratios, and the result of principal component analysis. As a con-sequence, it was concluded that the vehicle emissions in urban and sub -urban areas are likely to be a major contributor for PAH loadings in the ambient atmosphere during the non-heating season, while the contributions of residential heating and local industrial oil burning emissions were highly significant in heating season.son.

Relationship between noise and air pollution levels in Residential areas: comparison between roadside and non-roadside sites (소음과 대기오염도의 연계성에 대한 연구 - 일반주거지역의 도로 및 비도로지역의 비교)

  • Lee, Min-Hee;Park, Chan-Goo;Ryu, In-Cheol;Kim, Ki-Hyun
    • Analytical Science and Technology
    • /
    • v.24 no.5
    • /
    • pp.368-377
    • /
    • 2011
  • In this study, we analyzed the relationship between noise and air pollution from 6 residential sites from 6 districts in Seoul. The survey of all noise date obtained from 6 sites were also compared between road and nonroad area and between active (06:00-22:00) and inactive time bands (22:00-06:00). Comparison of the data between two time bands indicates that their differences are not large enough. On the other hand, if comparison of data is made by correlation analysis for road and non-road areas, strong correlations between noise levels and air pollution tend to be prevalent consistently in road area relative to the non-road area. In contrast, a correlation between noise levels and air pollution tends to decrease at the road area in inactive period relative to active period.

Distribution of Airborne Hexavalent Chromium Concentrations in Large Industrial Complexes in Korea

  • Kang, Byung-Wook;Lee, Hak-Sung;Kim, Jong-Ho;Hong, Ji-Hyung;Kim, Rok-Ho;Seo, Young-Kyo;Han, Jin-Seok;Baek, Kyung-Min;Kim, Min-Ji;Baek, Sung-Ok
    • Asian Journal of Atmospheric Environment
    • /
    • v.10 no.4
    • /
    • pp.208-216
    • /
    • 2016
  • This paper reports the results of a field evaluation which used sampling and analytical methods to determine the levels of airborne hexavalent chromium Cr(VI) in major industrial complexes in Korea over a seven year period (2007-2013). Cr(VI) concentrations were determined using cellulose filter sampling and ion chromatography analysis. In order to validate the analytical performance of these methods, studies were also carried out to investigate data quality control (QC) parameters, such as the method detection limit (MDL), repeatability, and recovery efficiencies. The average concentrations of Cr(VI) for the nine industrial complexes in Korea were in the range of 0.09 to $1.40ng/m^3$, which is similar to of the concentrations in other industrial areas around the world. The impacts of Cr(VI) emissions from industrial areas on Cr(VI) concentrations in neighboring-residential areas were considerably low, and the dispersion of Cr(VI) from industrial areas to residential areas was estimated to be 'not-significant'. Cr(VI) levels were not affected by seasonal variation, which suggests that chromium was emitted continuously from the industrial sources throughout the year. The concentration of Cr(VI) measured accounted for 0.7 to 9.4 percent of the total chromium level, which is a low percentage compared to those in other urban areas around the world. This is the first report in an international journal of a field study conducted in Korea to determine the concentration of Cr(VI) in the ambient air of industrial and residential areas.

Characteristics of Hazardous Air Pollutants in the Steel Industrial City, Pohang ( I ) - Polycyclic Aromatic Hydrocarbons (철강산업도시 포항지역 유해대기오염물질의 오염특성 ( I ) - 다환방향족탄화수소)

  • Baek, Kyung-Min;Seo, Young-Kyo;Cho, Byoung-Yoon;Baek, Sung-Ok
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.34 no.2
    • /
    • pp.233-243
    • /
    • 2018
  • This study was carried out to characterize the ambient levels of PAH concentrations in Pohang city, where steel industry has been intensively developed. A large amount of PAH emissions from steel production and related industries in Pohang are concerned about the environmental health hazards of nearby residents. TSP samples were seasonally collected during 10 days at four sites in Pohang from April to December 2010. Each sample was collected for 24 hours using high-volume air sampler. All samples were extracted by $soxtec^{TM}$ before concentration of 1.0 mL. The concentrates were analyzed by GC/MS. The prevailing wind direction was southwest and west-southwest in Pohang during the measurement period. Variations of TSP concentrations appeared to be similar between four sites. The highest TSP concentration was found in fall, while the lowest in summer. The highest PAH concentration was found at an industrial site, while the lowest at a residential/commercial site. In the case of BaP, the average concentration at the industrial site was $0.63{\pm}0.66ng/m^3$, which was approximately 2 times of the residential/commercial site. The paired t-test (p<0.05) showed significant differences between industrial and residential area. Particulate PAH concentrations were higher in the winter and lower in the summer. The concentrations of BaP in winter were 2~10 times higher than those in the other three seasons. This study clearly demonstrated the impact of steel industry on the elevated levels of PAH in Pohang city.

Component Analysis of Thermally Activated Building System in Residential Buildings

  • Chung, Woong June;Lee, Yu Ji;Yoo, Mi Hye;Park, Sang Hoon;Yeo, Myoung Souk;Kim, Kwang Woo
    • Architectural research
    • /
    • v.16 no.4
    • /
    • pp.203-210
    • /
    • 2014
  • The packaged terminal air conditioner, the typical cooling system for the residential buildings, consumes a large amount of electricity in a short period time during peak hours. In order to reduce the peak load and conserve the electricity, the thermally activated building system can be used as a secondary system to handle the partial cooling load. However, the thermally activated building system may cause condensation and under-cooling. Thus, design of both systems should be performed with careful investigation in characteristics of both systems to amplify the advantages. Since the thermally activated building system has the time-delay effect which may cause under-cooling, the system is designed to handle the base load of the building. Hence, simple simulation with EnergyPlus was performed to observe the characteristics of cooling load in residential buildings. Once the possible range of the load handling ratio of the thermally activated building system was decided, characteristics of system was analyzed in terms of hardware component and operation parameters. The hardware components were analyzed in plant and system aspects and the operation parameter was evaluated in the thermal comfort aspect. As the load handling ratio increased, the thermal comfort increased due to the lower radiant mean temperatures. Within the range of thermal comfort, the several adjustments were made in setpoint temperature and electricity consumptions of difference cases were observed to decide which components and parameters were important for designing the systems.