• Fire Science and Engineering
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• v.29 no.2
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• pp.13-19
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• 2015

Real scale fire tests was carried out for extinguishing performance evaluation of the wetting agent. The experiment was conducted in accordance with a Class A fire extinguishing test methods specified in the 'Type Approval of the Manual System Fire Extinguisher and Technical Standards of Test'. In addition, the subjects of this experiment were the wood flour and rice husk. Fire-fighting water, the three kinds of wetting agents used in the country and this study was used, was undertaken to determine a clear discrimination of the water and wetting agent. In the experimental results, it was confirmed that the internal temperature is maintained long time in the case of water. The internal temperature were rapidly lowered in the experiment of wetting agents. Therefore, the discrimination of extinguishing ability was confirmed by the temperature distribution in accordance with time. Based on the results of this experiment, this study is expected to be used as a underlying material on presenting a method of optimized performance evaluation of wetting extinguishing agent.

• Journal of the Korean housing association
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• v.18 no.2
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• pp.21-27
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• 2007

Various buildings constructed by environmentally friendly resources are being built in KOREA. Especially as the wood has distinctive ecological merits in comparison with reinforced concrete and brick, the buildings made by the wood are acknowledged with its superiority of ecological value. Enough field studies for their thermal environment, however, haven't been done. In this study, to investigate indoor environmental condition and occupants' response to it of Log Cabin in Gyeongsangnam-do Hamyang Country Jirisan Natural Recreation Forest, examination of indoor thermal environment and field subjective evaluation have been done in that fundamental information of thermal environment characteristics can be suggested. The results are following; 1) Thermal environment of the Log Cabins; Indoor and outdoor mean dry bulb temperature were $21.9^{\circ}C$ and $-3.1^{\circ}C$, and Indoor and outdoor average relative humidity were 25.8% and 52.1%. These results are below ASHRAE; dry bulb temp. $22.0^{\circ}C$, humidity 30%, and above domestic standards; dry bulb temp. $18{\sim}20.0^{\circ}C$, humidity $40{\sim}60%$. 2) Result of subjective evaluation; Thermal sensation and its comfort were evaluated as 'slightly uncomfortable' because of 'slightly warm'. And humid sensation and its comfort were evaluated as 'slightly uncomfortable' because of 'slightly warm'. 3) Result of vertical temperature and humidity; Vertical temperature difference from head to ankle was $0.54^{\circ}C$ which means most occupants may feel comfortable.

• Korean Journal of Materials Research
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• v.15 no.1
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• pp.73-77
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• 2005

Motivated by the enhanced magnetic properties of Mg-codoped GaMnN ferromagnetic semiconductors, Be-codoped GaMnAs films were grown via molecular beam epitaxy with varying Mn flux at a fixed Be flux. The structural, electrical, and magnetic properties were investigated. GaAs:(Mn,Be) films showed metallic behavior while GaAs:Mn films showed semiconducting behavior as determined by the temperature dependent resistivity measurements. The Hall-effect measurements with varying magnetic field showed clear anomalous Hall effect up to room temperature proving ferromagnetism and magnetotransport in the GaAs:(Mn,Be) films. Planar Hall resistance measurement also confirmed the properties. The dramatic enhancement of the Curie temperature in GaMnAs system was attributed to Be codoping in the GaMnAs films as well as MnAs precipitation.

• Safety and Health at Work
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• v.12 no.1
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• pp.119-126
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• 2021

Background: During the period 2001 to 2016, the maximum temperatures in Thailand rose from 38-41℃ to 42-44℃. The current occupational heat exposure standard of Thailand issued in 2006 is based on wet bulb globe temperature (WBGT) defined for three workload levels without a work-rest regimen. This study examined whether the present standard still protects most workers. Methods: The sample comprised 168 heat acclimatized workers (90 in construction sites, 78 in foundries). Heart rate and auditory canal temperature were recorded continuously for 2 hours. Workplace WBGT, relative humidity, and wind velocity were monitored, and the participants' workloads were estimated. Heat-related symptoms and signs were collected by a questionnaire. Results: Only 55% of the participants worked in workplaces complying with the heat standard. Of them, 79% had auditory canal temperature ≤ 38.5℃, compared with only 58% in noncompliant workplaces. 18% and 43% of the workers in compliant and noncompliant workplaces, respectively, had symptoms from heat stress, the trend being similar across all workload levels. An increase of one degree (C) in WBGT was associated with a 1.85-fold increase (95% confidence interval: 1.44-2.48) in odds for having symptoms. Conclusion: Compliance with the current occupational heat standard protects 4/5 of the workers, whereas noncompliance reduces this proportion to one half. The reasons for noncompliance include the gaps and ambiguities in the law. The law should specify work/rest schedules; outdoor work should be identified as an occupational heat hazard; and the staff should include occupational personnel to manage heat stress in establishments involving heat exposure.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.1
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• pp.67-73
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• 2022

The food cold chain refers to a technology and distribution supply chain applied to maintain a constant temperature suitable for the product from production (harvest) to delivery to consumers. In particular, in Korea, the insulation material used in the food cold chain is mostly EPS (Expanded Polystyrene), which is used as a transport container for various food cold chains. However, according to the government's eco-friendly policy, companies charge environmental contributions to the use of EPS, but due to its low price and convenience of handling, it is still used as a container for delivering food. In this study, in order to measure the domestic delivery environment of general refrigerated foods, changes in impact, temperature, and humidity during transport of the EPS packaging system containing foods and ice pack refrigerants were measured. As a result, there were 2?3 sections in which a high impact force of 40 G or more was generated during transport. This can cause damage to the product and EPS container. The difference in temperature and humidity changes by parcel transport routes is more than 30%, so it is necessary to present accurate standards for the domestic cold chain distribution environment. As a result of microbial experiments. the transportation period had a dominant effect on the increase in total viable count and E. coli count.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.474-477
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• 2021

Recently, in order to prevent the proliferation of COVID-19, which began in earnest in 2020, an increasing number of places have been measuring the temperature and required to wear a mask. However, as wearing a mask and checking the temperature are typically measured directly by a person or by a single individual positioned in front of the machine, standards may vary based on the person's manual measurement method, wasting workforce. While standing in front of a device often measures the maximum temperature of the face, the standard of fever is also unclear. Both approaches can create bottleneck situations when checking large numbers of people. Furthermore, it is unable to conduct periodic measurements and tracking because the measuring machines are generally put only at the entrance. Thus, this study suggests a method for preventing the spread of infectious diseases by automatically identifying and displaying unmasked people and those with fever in real-time using a general camera, a thermal imaging camera, and an artificial intelligence algorithm.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.479-483
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• 2008

There are no International Standards or Criteria pertaining to fires inside tunnels at the moment, but there are some fire-related regulations in some advanced countries such as Germany and the Netherlands where some fire-related studies have been expedited. Germany has established regulations related to the safety of structures by stipulating Fire Curves of RABT and EBA Tunnels. Also, the Netherlands has established the resistance capacity of structures by stipulating RWS curve so that they can prevent the adjacent area from being damaged due to a tunnel collapse. Hydrocarbon Fire Curve is the standard assessing the behaviour of a structure in a serious fire, by increasing the heating speed and the maximum temperature of ISO 834 Curve, while MHC Fire Curve, which was established in France, realizes more serious fire conditions. In this study, we aimed to develop the basis of full-sized experiments, with which you can assess the fire-resisting capacity against the fire strength of concrete PC panel lining, through the realization of various tunnel fire curves as mentioned above, by developing the heating furnace suitable for the requirements of Fire-Resisting Standards, with which you can assess the fire damage of tunnel concrete lining. We have developed various conditions of the heating furnace and the method to install a thermo couple within the furnace based on EFNARC and KS F2257-1. We have also conducted a calibrating experiment in order to secure its reliability.

• The Korean Journal of Malacology
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• v.32 no.3
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• pp.157-164
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• 2016

For the hygienic production of oyster at Goseong bay, this study investigated the marine bacteriological condition of the area from 2008 to April 2009. Average seawater temperature and salinity ranged $2.8-19.3.0^{\circ}C$ and 32.61-34.91 psu, respectively. The coliform group and fecal coliform of seawater ranged < 1.8-4,900 MPN/100 mL and < 1.8-700 MPN/100 mL, respectively. The coliform group of oyster (Crassostrea gigas) ranged < 1.8-13,000 MPN/100 g. Fecal coliform of oyster ranged and < 1.8-310 MPN/100 g. Only one of 140 samples was exceeded in the U.S NSSP standard (> 230 MPN/100 g) of fecal coliform. Fecal coliform in seawater was on the level of clean sea, below the U.S. NSSP standards, and the contents of fecal coliform and heavy metals in cultured oyster were also below the U.S. NSSP, heavy metal standards, showing that the sea area is bacteriologically safe.

• Journal of Energy Engineering
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• v.15 no.3 s.47
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• pp.202-208
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• 2006

Although the importance of good conservation of historic sites including ancient royal tombs is well aware, still not much attention has been paid for the facilities and systems to preserve those historic sites, which includes precious artifacts as wall paints and carved works, etc. Even the general understanding about the environment of the underground space or tombs is not satisfactory. In the present study, vibration levels due to the operation of an HVAC system to maintain the desired indoor temperature and humidity are investigated experimentally. According to the measured data, the level of vibration inside the present model tomb with the indoor unit inside, showed order of magnitude less values than the Swiss Standards, but still higher than the value suggested by German standards, which is, zero. Further study will be pursued for cases including different ways of installation, because the vibration level depends not only on the system design, but also on the installation methods.

• Analytical Science and Technology
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• v.12 no.2
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• pp.130-135
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• 1999

A graphite furnace atomic absorption spectrometry (GFAAS) with matrix modification has been used to determine trace amounts of arsenic, lead and selenium in rice flour samples. A mixed solution of palladium and magnesium nitrate was used as a matrix modifier to convert the analyte elements into a phase of higher thermostability and to increase the volatility of concomitants in graphite furnace. Matrix modification effects by the mixed solution were investigated for several elements (As, Cd, Cu, Pb, Se, Zn). It has been found that the matrix modifier substantially increase the pyrolysis and atomization temperature, and absorbance for As, Pb and Se. The concentration of As, Pb and Se in rice flour samples were determined by standard addition method with Zeeman background correction after microwave acid digestion. In this method the characteristic concentrations of As, Pb and Se are 26 ng/g, 18 ng/g, 24 ng/g on the basis of dry sample respectively.