• Title/Summary/Keyword: hot and cold environment

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The "Warm Zone" Cases: Environmental Monitoring Immediately Outside the Fire Incident Response Arena by Firefighters

  • Caban-Martinez, Alberto J.;Kropa, Bob;Niemczyk, Neal;Moore, Kevin J.;Baum, Jeramy;Solle, Natasha Schaefer;Sterling, David A.;Kobetz, Erin N.
    • Safety and Health at Work
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    • v.9 no.3
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    • pp.352-355
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    • 2018
  • Hazardous work zones (i.e., hot, warm, and cold) are typically established by emergency response teams during hazardous materials (HAZMAT) calls but less consistently for fire responses to segment personnel and response activities in the immediate geographic area around the fire. Despite national guidelines, studies have documented the inconsistent use of respiratory protective equipment by firefighters at the fire scene. In this case-series report, we describe warm zone gas levels using multigas detectors across five independent fire incident responses all occurring in a large South Florida fire department. Multigas detector data collected at each fire response indicate the presence of sustained levels of volatile organic compounds in the "warm zone" of each fire event. These cases suggest that firefighters should not only implement strategies for multigas detector use within the warm zone but also include respiratory protection to provide adequate safety from toxic exposures in the warm zone.

Spatio-Temporal Variability of Temperature and Precipitation in Seoul

  • Choi, Hyun-Ah;Lee, Woo-Kyun;Kim, So-Ra;Kwak, Han-Bin
    • Spatial Information Research
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    • v.16 no.4
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    • pp.467-478
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    • 2008
  • This study analyzes the spatial and temporal variability of temperature ($^{\circ}C$) and precipitation (mm) in Seoul, Korea. The temperature and precipitation data were measured at 31 automatic weather stations (AWSs) in Seoul for 10 years from 1997 to 2006. In this study, inverse distance squared weighting (IDSW) was applied to interpolate the non-measured spaces. To estimate the temperature and precipitation variability, the mean values and frequencies of hot and cold days were examined. The maximum and minimum temperatures were $32.80^{\circ}C$ in 1999 and $-19.94^{\circ}C$ in 2001, respectively. The year 2006 showed the highest frequency of hot temperatures with 79 hot days, closely followed by 2004 and 2005. The coldest year was in 2001 with 105 cold days. The annual mean temperature and precipitation increased by about $1^{\circ}C$ and 483mm during the 10-year period, respectively. The temperature variability differed between high-elevation forested areas and low-elevation residential areas. However, the precipitation variability showed little relation with the topography and land use patterns.

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Determination of Phenolic Contents in Rooibos (Asphalthus linearis) Tea Depending on the Steeping Temperature and Time (루이보스차(Asphalthus linearis)의 추출방법에 따른 페놀릭류 함량 변화연구)

  • Park, Sin-Hee;Do, Yung-Suk;Kim, Youn-Sung;Kim, Nan-Young;Lee, Jin-Hee;Kim, Jong-Hwa;Yoon, Mi Hye
    • Journal of Food Hygiene and Safety
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    • v.32 no.5
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    • pp.389-395
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    • 2017
  • A simultaneous determination of 5 phenolic acids (gallic acid, chlorogenic acid, caffeic acid, pcoumaric acid, trans ferulic acid) and 9 flavonoids (procyanidin b1, aspalathin, rutin, vitexin, hyperoside, isoquercitrin, luteolin, quercetin, chrysoeriol) in rooibos tea has been carried out by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). A validated analysis method in this study was applied to rooibos aqueous infusions. Rooibos tea is an antioxidant-rich tea which has anti-cancer, anti-aging, anti-inflammatory, anti-diabetic effect. Extraction yield of phenolics depends on steeping time and temperature of water. Tea infusions were prepared by placing 1 g of tea leaves or 1 tea bag in 100 mL of boiled water, and then at 3, 6 and 30 minutes intervals the infused teas were taken to carry out the analysis of phenolic contents. Another tea infusion was conducted with cold water ($25-30^{\circ}C$) for 30 minuntes. As a result, the total amount of phenolics was highest in rooibos tea steeped with hot water for 30 minutes, followed by 6 minutes, 3 minutes and cold water 30minutes and the result has statistical significance.

A Study on Concrete Curing Quality Management Based on Various Test of Construction Condition under Hot Weather Circumstance (서중(暑中) 환경에서 현장 콘크리트 시험을 통한 양생 품질관리 방안)

  • Park, Shin
    • Korean Journal of Construction Engineering and Management
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    • v.7 no.2 s.30
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    • pp.71-80
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    • 2006
  • It is required to study systematical on the concrete quality management to extend structure life because rebuilding effect is reducing under present condition of large sized and high stories structure. Concrete, which shows its intensity by hydrating action and a big change in quality according to hot weather and temperature, produces a lot of quality problem under hot and cold weather. Because of each specification and construction plan which does not have basic standard on site, concrete's quality is irregular and makes some defect. As a result, Dae-gu is fumed out to be the longest area after investigating application period and days focused on 8 cities weather information about t relationship between hot weather circumstance and construction environment. Therefore, we first surveyed the curing construction processing in the region and found out the problem of quality management. Then figure out the way of solution. Moreover, we integrated curing quality management, which is applied differently to each site, to have equal quality and to reduce defect from construction site. And then, based on various test of construction condition and analysis of quality management item, we suggest effective concrete quality management to make curing construction standard guide and plan under hot weather.

ABRN:An Adaptive Buffer Replacement for On-Demand Multimedia Database Service Systems (ABRN:주문형 멀티미디어 데이터 베이스 서비스 시스템을 위한 버퍼 교체 알고리즘)

  • Jeong, Gwang-Cheol;Park, Ung-Gyu
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.7
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    • pp.1669-1679
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    • 1996
  • In this paper, we address the problem of how to replace huffers in multimedia database systems with time-varying skewed data access. The access pattern in the multimedia database system to support audio-on-demand and video-on-demand services is generally skewed with a few popular objects. In addition the access pattem of the skewed objects has a time-varying property. In such situations, our analysis indicates that conventional LRU(least Recently Used) and LFU(Least Frequently Used) schemes for buffer replacement algorithm(ABRN:Adaptive Buffer Replacement using Neural suited. We propose a new buffer replacement algorithm(ABRN:Adaptive Buffer Replacement using Neural Networks)using a neural network for multimedia database systems with time-varying skewed data access. The major role of our neural network classifies multimedia objects into two classes:a hot set frequently accessed with great popularity and a cold set randomly accessed with low populsrity. For the classification, the inter-arrival time values of sample objects are employed to train the neural network.Our algorithm partitions buffers into two regions to combine the best roperties of LRU and LFU.One region, which contains the 핫셋 objects, is managed by LFU replacement and the other region , which contains the cold set objects , is managed by LRUreplacement.We performed simulation experiments in an actual environment with time-varying skewed data accsee to compare our algorithm to LRU, LFU, and LRU-k which is a variation of LRU. Simulation resuults indicate that our proposed algorthm provides better performance as compared to the other algorithms. Good performance of the neural network-based replacement scheme means that this new approach can be also suited as an alternative to the existing page replacement and prefetching algorithms in virtual memory systems.

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Impact of Salt Intake on Red and Fallow Deer Production in Australia - Review -

  • Ru, Y.J.;Glatz, P.C.;Miao, Z.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.12
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    • pp.1779-1787
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    • 2000
  • Southern and south-western Australia is a typical mediterranean environment, characterised by wet, cold winters and dry, hot summers. The evaporation rate varies significantly in summer, resulting in a high salinity of drinking water for grazing animals. In addition, a large amount of land in the cropping areas is affected by salt. Puccinellia, tall wheat grass and saltbushes have been planted to improve the soil condition and to supply feed for grazing animals. Animals grazing these areas often ingest an excessive amount of salt from soil, forage and drinking water which can reduce feed intake, increase the water requirement, depress growth and affect body composition as demonstrated in sheep. While the deer industry has been successfully developed in these regions, the potential impact of excessive salt intake on deer production is unknown. The salt tolerance has been well defined for sheep, cattle and other livestock species, but the variation between animal species, breeds within species, maturity status and grazing environments makes it impossible to apply these values directly to deer. To optimise deer production and effectively use natural resources, it is essential to understand the salt status of grazing deer and the impact of excessive salt intake on growth and reproduction of deer.

Climate Change and Health - A Systemic Review of Low and High Temperature Effects on Mortality (기후변화와 건강 - 저온과 고온이 사망에 미치는 영향에 관한 체계적 고찰)

  • Lim, Youn-Hee;Kim, Ho
    • Journal of Environmental Health Sciences
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    • v.37 no.6
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    • pp.397-405
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    • 2011
  • Objectives: The impact of climate change on the health has been of increasing concern due to a recent temperature increase and weather abnormality, and the research results of the impact varied depending on regions. We synthesized risk estimates of the overall health effects of low and high temperature taking account of the heterogeneity. Methods: A comprehensive literature search was conducted using PUBMED to identify journal articles of low and/or high temperature effects on mortality. The search was limited to the English language and epidemiological studies using time-series analysis and/or case-crossover design. Random-effect models in meta analysis were used to estimate the percent increase in mortality with $1^{\circ}C$ temperature decrease or increase with 95% confidence intervals (CI) in cold or hot days. Results: Twenty three studies were presented in two tables: 1) low temperature effects; 2) high temperature effects on mortality. The combined effects of low and high temperatures on total mortality were 2% (95% CI, 1-4%) per $1^{\circ}C$ decrease and 4% (95% CI, 2-5%) per $1^{\circ}C$ increase of temperature, respectively. Conclusions: This meta analysis found that both low and high temperatures affected mortality, and the magnitude of high temperature appeared to be stronger than that of low temperature.

Neuro-fuzzy based prediction of the durability of self-consolidating concrete to various sodium sulfate exposure regimes

  • Bassuoni, M.T.;Nehdi, M.L.
    • Computers and Concrete
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    • v.5 no.6
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    • pp.573-597
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    • 2008
  • Among artificial intelligence-based computational techniques, adaptive neuro-fuzzy inference systems (ANFIS) are particularly suitable for modelling complex systems with known input-output data sets. Such systems can be efficient in modelling non-linear, complex and ambiguous behaviour of cement-based materials undergoing single, dual or multiple damage factors of different forms (chemical, physical and structural). Due to the well-known complexity of sulfate attack on cement-based materials, the current work investigates the use of ANFIS to model the behaviour of a wide range of self-consolidating concrete (SCC) mixture designs under various high-concentration sodium sulfate exposure regimes including full immersion, wetting-drying, partial immersion, freezing-thawing, and cyclic cold-hot conditions with or without sustained flexural loading. Three ANFIS models have been developed to predict the expansion, reduction in elastic dynamic modulus, and starting time of failure of the tested SCC specimens under the various high-concentration sodium sulfate exposure regimes. A fuzzy inference system was also developed to predict the level of aggression of environmental conditions associated with very severe sodium sulfate attack based on temperature, relative humidity and degree of wetting-drying. The results show that predictions of the ANFIS and fuzzy inference systems were rational and accurate, with errors not exceeding 5%. Sensitivity analyses showed that the trends of results given by the models had good agreement with actual experimental results and with thermal, mineralogical and micro-analytical studies.

Sea Cucumber Apostichopus japonicas Growth in Pond-bottom and Lantern-net Cultures (노지양식장에서 채롱양식과 바닥양식에 따른 해삼(Apostichopus japonicus)의 성장특성)

  • Jeong, U-Cheol;Han, Jong-Cheol;Kang, Seok-Joong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.49 no.3
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    • pp.337-342
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    • 2016
  • Sea cucumbers have been an important part of human diets throughout history; demand is increasing every year, making the species a target for coastal resource development. New harvesting technologies have been developed in response to demand, including nursery production and insemination aquaculture, but such methods produce relatively few individuals and productivity per unit area is very small. For example, captures are prohibited during July and August due to the breeding season, and sea cucumbers aestivate during the hot season and hibernate during the cold season, all factors that limit natural-environment production in Korea. Problems with slow growth of sea cucumbers have been encountered in previous rearing experiments. To assess the importance of feeding ecology on sea cucumber growth, we conducted pond-bottom and lantern-net culture experiments. Results showed that sea cucumbers in bottom cultures grew from 3.06 to 102.59 g, but those in lantern cultures only grew from 25.60 to 28.03 g.

A study of solitary wave trains generated by an injection of a blob into plasmas

  • Choe, Jeong-Rim;DokGo, Gyeong-Hwan;Choe, Eun-Jin;Min, Gyeong-Uk;Lee, Eun-Sang
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.93.1-93.1
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    • 2012
  • In this study, we investigated the generation of consecutive electrostatic solitary waves (ESWs) using by one-dimensional electrostatic particle-in-cell (PIC) simulation. For a given Gaussian perturbation, it is found that electron two-stream instability occurs in local grids region. Thus because of this instability, the electrostatic potential grows rapidly so as to be separated into electron and ion in perturbation region, and then electrons are trapped with heating during growing instability. It is found that these heated and trapped electrons are caused the generation of ESW, and ions are reflected backward and forward at the boundary of the initial perturbation, then form cold ion beam whereas electrons are confined to inside of the potential. Furthermore backward reflected ion beam forms ion holes by ion two-stream instability. On the other hand, as the confined electrons are released, and then released electrons also form hot electron beam, which play an important role in the generation of consecutive ESWs such as broadband electrostatic noise (BEN) observed frequently in space environment. Therefore the reason of the generation of consecutive ESWs is the existence of heated electrons which can sufficiently support energy to produce ESWs.

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