• Fire Science and Engineering
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• v.26 no.5
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• pp.13-20
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• 2012

Many fire-fighters suffer from the burn injuries, and the severe burns are the most catastrophic injury a person can survive, resulting in pain, emotional stress, and tremendous economic costs. It is important to understand the physiology of burns for prevention from skin burns and a successful treatment of a burn patient. But a few researches have been presented because the complex physical phenomena of our inside body like non-linearity characteristics of human skin make them difficult. Thus in this study, thermal analyses of biological tissues exposed to a flash fire causing severe tissue damage were studied by using a finite difference method based on the Pennes bio-heat equation. The several previous models for skin thermo-physical properties were summarized, and the calculated values with those models of tissue injury were compared with the results obtained by the previous experiment for low heat flux conditions. The skin models with good agreement could be found. Also, the skin burn injury prediction results with the best model for high heat flux conditions by flash flame were suggested.

• Fire Science and Engineering
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• v.18 no.4
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• pp.86-92
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• 2004

We tested five specimens of each species at each of five constant external heat flux levels (10, 15, 20, 25. and 35㎾/㎡). An Cone heater was used to expose the wood specimens to the heat flux. The 100-by 100-by 50-㎜ specimens were of four species: Redwood, White oak, Douglas fir, Maple. In result of test, charring of wood exposed to a constant external heat flux can be considered a linear with function of time. As compared with the charring rates Redwood is most rapidly, but on the other hand Douglas fir is most slowly. When the external heat flux is 35㎾/㎡, the charring rate is rapidly about twice then 10㎾/㎡. Using the Equation (2), the estimates for u were 1.02, 1.16, 1.23, 1.32, and 1.44 for the 10, 15, 20, 25, and 35 kw/m2 constant external exposure levels, respectively.

• International Journal of Industrial Entomology and Biomaterials
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• v.16 no.1
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• pp.21-27
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• 2008

The expression of heat shock protein genes (Hsp 70, Hsp 40, Hsp 20.8 and Hsp 20.4) against thermal stress in silkworm Bombyx mori was performed through semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Upon exposure of silkworm to two temperature regimes ($38^{\circ}C$ and $42^{\circ}C$), significant change in the expression of Hsp gene was observed as compared to the control. Hsp 70 and Hsp 40 showed increased expression than the small heat shock protein genes Hsp 20.8 and Hsp 20.4. The Hsp 70 showed increased expression during the recovery period as compared to 1 hr thermal treatments ($38^{\circ}C$/1 hr and $42^{\circ}C$/1 hr). Whereas, Hsp 40, Hsp 20.8 and Hsp 20.4 genes showed higher expression level at initial stages that later gradually decrease during recovery period. Tissue specific expression of Hsp 70 showed variation in the level of expression amongst the tissues. The mid gut and fat body tissues showed higher expression than the cuticle and silk gland tissue. The Hsp 70, Hsp 40 gene expression was analyzed in thermotolerant (Nistari) and thermo susceptible silk worm strain (NB4D2) and results showed significant variation in their expression level. The Nistari showed higher expression of Hsp 70 and Hsp 40 genes than the NB4D2. These findings provide a better understanding of cellular protection mechanisms against environmental stress such as heat shock, as these Hsps are involved in an organism thermotolerance.

• Journal of Wetlands Research
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• v.21 no.4
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• pp.344-353
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• 2019

Heat waves are a global phenomenon that exacerbate the risks associated with heat exposure and cause fatal human injury. The subject of this study was tropical night, one of the forms of heat waves. In this study, we investigated how the trend of tropical night in Korea is changing. From 1973 to 2018, we analyzed the temporal changes of the six tropical nights using daily minimum air temperature at 60 ASOS stations in Korea Meteorological Administration. From these analyzes, 10 sites were selected as attention sites for tropical nights: Incheon, Gangneung, Cheongju, Jeonju, Gwangju, Jangheung, Yeosu, Geoje, Gumi, Yeongdeok. The severe sites for tropical nights were identified as 14 sites including Hongcheon, Yangpyeong, Suwon, Wonju, Boryeong, Daejeon, Buan, Jeongeup, Mokpo, Geochang, Miryang, Pohang, Jeju, and Seogwipo. At the severe sites identified, special tropical night measures will need to be established.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.1242-1242
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• 2022

Annually, several construction workers fall ill, are injured, or die due to heat-related exposure. The prevalence of work-related heat illness may rise and become an issue for workers operating in temperate climates, given the increase in frequency and intensity of heatwaves in the US. An increase in temperature negatively impacts physical exertion levels and mental state, thereby increasing the potential of accidents on the job site. To reduce the impact of heat stress on workers, it is critical to develop and implement measures for monitoring physical exertion levels and mental state in hot conditions. For this, limited studies have evaluated the utility of wearable biosensors in measuring physical exertion and mental workload in hot conditions. In addition, most studies focus solely on male participants, with little to no reference to female workers who may be exposed to greater heat stress risk. Therefore, this study aims to develop a process for objective and continuous assessment of worker physical exertion and mental workload using wearable biosensors. Physiological data were collected from eight (four male and four female) participants performing a simulated drilling task at 92oF and about 50% humidity level. After removing signal artifacts from the data using multiple filtering processes, the data was compared to a perceived muscle exertion scale and mental workload scale. Results indicate that biosensors' features can effectively detect the change in worker physical and mental state in hot conditions. Therefore, wearable biosensors provide a feasible and effective opportunity to continuously assess worker physical exertion and mental workload.

• Journal of Korean Academy of Nursing
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• v.13 no.2
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• pp.87-104
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• 1983

It has been well documented that animals exposed to cold show increased activity of thyroid gland. The calorigenic action of thyroid hormone has been demonstrated by a variety of in vivo and in vitro studies. According to Edelman et al., the thyroid thermogenesis is due to activation of energy consuming processes, especially the active sodium transport by the hormone in target tissues. If so, the increase in thyroid activity during cold exposure should induce increased capacity of sodium transport in target tissue and the change in tissue metabolism should be precisely correlated with the change in Na+_K+_ATPase activity of the tissue. This possibility was tested in the present study: in one series, changes in oxygen consumption and Na+_K+_-ATPase activity of liver preparations were measured in rats as a function of thyroid status, in order to establish the effect of thyroid hormone on the tissue respiration and enzyme system in another series, the effect of cold stimulus on the serum thyroid hormone level, hepatic tissue oxygen consumption and Na+_K+_ATPase activity in rats. The results obtained are as follows: 1. The Na+_dependent oxygen consumption of liver slices, the oxygen consumption of liver mitochondria and the Na+_K+_ATPase activity of liver preparations were significantly inhibited in hypothyroidism and activated in hyperthyroidism. Kinetic analysis indicated that the Vmax. of Na+_K+_ATPase was decreased in hypothyroidism and increased in hyperth)'roidism. 2. In cold exposed rats, the serum triiodothyronine (T₃) level increased rapidly during the initial one day of cold exposure, then declined slowly to the control level after two weeks. The serum thyroxine (T₄) level decreased gradually throughout the cold exposure. Accordingly the T₃/T₄ratio increased. The mitochondrial oxygen consumption and the Na+_dependent oxygen consumption of liver slices increased during the first two days and then remained unchanged thereafter The activity of the Na+_K+_ATPase in liver preparations increased during cold exposure with a time course similar to that of oxygen consumption. Kinetic analysis indicated that the Vmax. of Na+_K+_ATPase increased. 3. Once the animal was adapted to cold, induction of hypothyroidism did not significantly alter the hepatic oxygen consumption and Na+_K+_ATPase activity. These results indicate that: 1) thyroid hormone increases capacities of mitochondrial respiration and active sodium transport in target tissues such as liver; 2) the increased T₃level during the initial period of cold exposure facilitates biosynthesis of Na+_K+_ATPase and mitochondrial enzymes for oxidative phosphorylation, leading to enhanced production and utilization of ATP, hence heat production.

• International Journal of High-Rise Buildings
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• v.10 no.4
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• pp.345-364
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• 2021

Developments in the understanding of fire behaviour for large open-plan spaces typical of tall buildings have been greatly outpaced by the rate at which these buildings are being constructed and their characteristics changed. Numerous high-profile fire-induced failures have highlighted the inadequacy of existing tools and standards for fire engineering when applied to highly-optimised modern tall buildings. With the continued increase in height and complexity of tall buildings, the risk to the occupants from fire-induced structural collapse increases, thus understanding the performance of complex structural systems under fire exposure is imperative. Therefore, an accurate representation of the design fire for open-plan compartments is required for the purposes of design. This will allow for knowledge-driven, quantifiable factors of safety to be used in the design of highly optimised modern tall buildings. In this paper, we review the state-of-the-art experimental research on large open-plan compartment fires from the past three decades. We have assimilated results collected from 37 large-scale compartment fire experiments of the open-plan type conducted from 1993 to 2019, covering a range of compartment and fuel characteristics. Spatial and temporal distributions of the heat fluxes imposed on compartment ceilings are estimated from the data. The complexity of the compartment fire dynamics is highlighted by the large differences in the data collected, which currently complicates the development of engineering tools based on physical models. Despite the large variability, this analysis shows that the orders of magnitude of the thermal exposure are defined by the ratio of flame spread and burnout front velocities (V_S / V_BO), which enables the grouping of open-plan compartment fires into three distinct modes of fire spread. Each mode is found to exhibit a characteristic order of magnitude and temporal distribution of thermal exposure. The results show that the magnitude of the thermal exposure for each mode are not consistent with existing performance-based design models, nevertheless, our analysis offers a new pathway for defining thermal exposure from realistic fire scenarios in large open-plan compartments.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.159.2-159.2
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• 2010

Asbestos is the collective name for a group of naturally occurring minerals in their fibrous form and hydrous silicates of magnesium and a mineral fiber that has been used commonly in a variety of building construction materials for insulation and as a fire-retardant. Asbestos has been used for a wide range of manufactured goods, because of its fiber strength and heat resistant properties. Nevertheless harmful of asbestos is quite serious. Exposure to airborne friable asbestos may result in a potential health risk because persons breathing the air may breathe in asbestos fibers. Continued exposure can increase the amount of fibers that remain in the lung. Fibers embedded in lung tissue over time may cause serious lung diseases including asbestosis, lung cancer. In this paper, we carried out as fundamental study for dispose of asbestos cement slate safely and perfectly. Melting Temperature of asbestos need to more than $1,520^{\circ}C$ and specially asbestos cement slate need more energy than that of pure asbestos. We need to decrease melting temperature of asbestos cement slate for economical efficiency. To the purpose, glass and bottom ash were chosen as additives for basicity control. we analyzed about properties of asbestos cements slate, melting characteristics on the additives ratio and temperature. We confirmed about harmlessness of melting slag through analysis of scanning electron microscope(SEM) and x-ray diffractometer(XRD).

• Applied Biological Chemistry
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• v.41 no.8
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• pp.578-582
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• 1998

Grape seed oil was characterized to assess the usefulness in the food industry. Among the various oils, the initial antioxidant activity was the highest for grape seed oil. Heating the oil at $180^{\sim}C$ for 20 min retained 86% of the initial activity. Grape seed and sesame oils showed a low peroxide value, about 2, implying a less oxidative reaction. The oxidation of grape seed oil was increased to a less extent by heat-treatment than other oils. Light exposure for 1 month resulted in a slight decrease in the antioxidant activity of grape seed oil, maintaining 96% of the initial activity. Other oils were all light-susceptible and the activities decreased significantly. The peroxide values of all the oils increased by light exposure, but the extent of oxidation was still the least for grape seed oil. The addition of grape seed oil to perilla oil was very effective, in that the peroxide value was 5-times decreased by 1 : 5 composition of grape seed oil versus perilla oil. These results indicate that grape seed oil can be used as a good cooking oil or an additive for other oils.

• Journal of Sensor Science and Technology
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• v.26 no.3
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• pp.204-208
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• 2017

Highly uniform and well-dispersed Zeolitic Imidazolate Framework-7 (ZIF-7) particles were prepared by the precipitation of $Zn^{2+}$ using benzimidazole, which were converted into ZnO nanoparticles by heat treatment at $500^{\circ}C$ for 24 h. The ZIF-7 derived ZnO nanoparticles showed abundant mesopores, high surface area, and good dispersion. The gas sensing characteristics toward 5 ppm acetone, ethanol, trimethylamine, ammonia, p-xylene, toluene, benzene, and carbon monoxide and carbon dioxide were investigated at $350-450^{\circ}C$. ZIF-7 derived ZnO nanoparticles exhibited high response to 5 ppm acetone ($R_a/R_g=57.6$; $R_a$: resistance under exposure to the air, Rg: resistance under exposure to the gas) at $450^{\circ}C$ and negligible cross-responses to other interference gases (trimethylamine, ammonia, p-xylene, toluene, benzene, carbon monoxide, carbon dioxide) and relatively low responses to ethanol. ZIF derived synthesis of metal oxide nanoparticles can be used to design high performance acetone sensors.