• Journal of Soil and Groundwater Environment
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• v.27 no.3
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• pp.11-21
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• 2022

The purpose of this study was to evaluate the influences of digestion temperature on the extraction of heavy metals from soil using the standard method established by Korean Ministry of Environment (KMES). A total of 7 heavy metals (As, Cd, Cr, Cu, Ni, Pb and Zn) in soil samples were extracted at varying digestion temperatures [(66 ± 2.0)℃, (73 ± 1.9)℃, (80 ± 1.3)℃, (85 ± 1.7)℃, (92 ± 2.0)℃, (98 ± 1.7)℃]. As, Cd, Cu, Pb and Zn concentrations remained relatively constant over the temperature range, but Ni and Cr concentrations greatly varied with the digestion temperature. The extent of variation in extraction efficiencies as compared to the concentration obtained at 66℃ was in following order; Ni (7.09% ~ 35.42%) > Cr (4.79% ~ 25.40%) > Zn (3.99% ~ 17.52%) > Cu (2.22% ~ 19.34%) > As (3.54% ~ 8.26%) > Cd (-5.08% ~ 1.08%) > Pb (-4.71% ~ -1.70%). The accuracy for certified reference materials at the digestion temperature of 80 and 85℃ was 98.7% ~ 105.8%. Therefore, digestion temperature of 80℃ ~ 85℃ is suggested to obtain reliable and reproducible data when the standard method by Korean Ministry of Environment is employed to analyze multiple heavy metal components in soil samples.

• Journal of Hydrogen and New Energy
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• v.26 no.2
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• pp.184-191
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• 2015

As the power electronics system increases the frequency, the power loss and thermal management are paid more attention. This research presents a real time model of dissipation power with junction temperature response for 120kw IGBT inverter which is applied to the thermal management of high power IGBT inverter. Since the computational time is critical for real time simulation, look-up tables of IGBT module characteristic curve are implemented. The power loss from IGBT provides a clue to calculate the temperature of each module of IGBT. In this study, temperature of each layer in IGBT is predicted by lumped capacitance analysis of layers with convective heat transfer. The power loss and temperature of layers in IGBT is then communicated due to mutual dependence. In the dynamic model, PWM pulses are employed to calculation real time IGBT and diode power loss. Under Matlab/Simulink$^{(R)}$ environment, the dynamic model is validated with experiment. Results showed that the dynamic response of power loss is closely coupled with effective thermal management. The convective heat transfer is enough to achieve proper thermal management under guideline temperature.

• Fashion & Textile Research Journal
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• v.22 no.2
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• pp.240-249
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• 2020

This study reviews studies that used skin temperature in order to establish an emotion evaluation protocol based on skin temperature for home appliances. A survey of skin temperature evaluation papers was conducted by the following five stages: (1) keyword search, (2) title screening, (3) abstract screening, (4) full paper screening, and (5) relevance evaluation. Selected papers were reviewed for: purpose, recruitment criteria of participants, the number of participants, apparatus, procedure, measures, analysis methods, and major findings. Thermistor sensors and thermography are used for the measurement of skin temperature. Skin temperature sensors are attached to 4 - 10 locations on the body and their mean of skin temperature is calculated by Ramanatan's 4-point or Hardy & Dubois's 7-point method. Semantic differential (SD) method and thermography measuring facial surface temperature have been used for emotion evaluation. The SD method provides a set of adjective pairs related to a product and evaluates changes in emotion from the use of the product. The range of facial surface analyzed is defined in the thermal image and temperature changes before and after the evaluation are analyzed. The evaluation items of home appliances include form, color, material, aesthetics, satisfaction, novelty, convenience, pleasantness, and excellence. Many existing emotion studies using skin temperature do not apply physiological and psychological methods. This study provides basic data to establish a skin temperature and emotion evaluation protocol by examining literature for skin temperature and evaluation of sensitivity.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.273-276
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• 2007

A natural graphite heat spreader increased the upper operating temperature limit of a CCFL backlit LCD television. A 0-80W heat source was used to simulate additional electronics. Without the heat spreader, internal circuitry shut-down at ${\sim}30;$ no shut-down occurred above 80W with a heat spreader. Additionally, brightness, temperature uniformity, and operating ranges were improved, verified by environmental chamber performance testing at various ambient conditions.

• Journal of the Korea Safety Management & Science
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• v.13 no.2
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• pp.61-66
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• 2011

Fire disasters have frequently happened in concrete structures, which resulted in severe structural damages and unsafety. In this case, the method which had evaluated the safety of damaged structures was often unaccepted from most of stakeholders and engineers. The objective of this study is to develope the procedure and method to be able to determine the safety. Numerical simulation was applied to produce the maximum temperature and temperature distribution. Nextly, temperature propagation analysis was performed to plot temperature gradients at each depth and location. The material strength curve versus temperature was applied to determine the safety of concrete structures damaged by fire. The maximum temperature should be calibrated considering real fire records ; magnitude, intensity, situation etc. The results shows that the selected procedure and method was applicable and practical.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.6
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• pp.852-856
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• 2015

Demand side management (DSM) program has been frequently used for reducing the system peak load because it gives utilities and independent system operator (ISO) a convenient way to control and change amount of electric usage of end-use customer. Planning and operating methods are needed to efficiently manage a DSM program. This paper presents a planning method for DSM program. A planning method for DSM program should include an electric load forecasting, because this is the most important factor in determining how much to reduce electric load. In this paper, load forecasting with the temperature stochastic modeling and the sensitivity to temperature of the electric load is used for improving load forecasting accuracy. The proposed planning method can also estimate the required day, hour and total capacity of DSM program using Monte-Carlo simulation. The results of case studies are presented to show the effectiveness of the proposed planning method.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.5
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• pp.725-732
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• 2020

The sudden drop of water temperature in winter is very threatening factor that affects the productivity of farmed fish and the management in aquafarm. In this study, we investigated the effect of low temperature on the survival, oxygen consumption and stress responses of parrotfish Oplegnathus fasciatus due to acute drop of water temperature. The survival rate of parrotfish Oplegnathus fasciatus was 5% at 6℃, 95% at 8℃ and 100% at 10℃ on the 4^th day of exposure in each experimental temperature. Low-lethal temperature for 4days of parrotfish Oplegnathus fasciatus (4 day-LT₅₀) was 6.99℃ (confidence limit, 6.55-7.42℃). Oxygen consumption rate was significantly decreased with decreasing water temperature. Temperature coefficient (Q₁₀) was found to be 4.0 between 10℃ and 8℃ and 0.39 between 8℃ and 6℃. As a result of investigating the stress response according to the drop in water temperature, the concentration of SOD (Superoxide dismutase), cortisol, glucose, total Ig, AST (Aspartate) and ALT (Alanine aminotransferase) increased with decreasing of water temperature. This study would be useful for the management of temperature about cultured fish.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.6432-6438
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• 2015

In this paper, we analyzed by measuring the temperature and humidity inside of the Feed Bin, NV, EA, SA, $SA{\cdot}EA$, by applying the ventilation system offers an efficient management of the operating direction. In the period the target is not input and feed period to make a change in the Feed Bin within the temperature and humidity of the outdoor air temperature and relative humidity compared to accept the ventilation system. Internal temperature over a comparison of the external temperature and the relative humidity is $SA{\cdot}EA$, internal humidity can verify the efficiency and NV, SA ventilation applied.

• Journal of the Korean Society of Food Culture
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• v.11 no.2
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• pp.235-242
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• 1996

Sanitary management practices from 8 packaged meals (Dosirak) manufacturing establishments were surveyd during production and distribution and their microbiological quality of dosirak items marketed in CVS were analyzed. Correlation coefficients were calculated to deternine significant relationships between sanitary management practices and microbiological quality of packaged meals. The results of self evaluation on sanitary management practices indicated 'doing practice well' in personnel and equipment sanitation management but time-temperature control management were practiced satisfactorily only about 55% as compared with the managerial standard guidelines. Significant relationships between the status of actual sanitary management practices and microbiological quality of Dosirak items were not found, but general status of microbiological quality of Dosirak items revealed positive relationship with the size of operational structure and the status of time-temperature control management practices.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.231-234
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• 2013

According to the recent development of USN technology, it has been applied in various fields of construction management. In particular, the concrete curing management using the wireless measurement system is actively being conducted. However, the existing method has limitations such as the reinstallation of temperature sensors and repositioning of repeaters. It is also not easy to acquire the measured data. Thus, this study focuses on the concrete curing management. This study proposes data acquisition method using the smartphone on construction site and tests applicability of the data measuring device and the smartphone. The test allows us to suggest the actual communication distance on construction site and to determine the correction value that is applied to the measured temperature. The data acquisition method proposed in this study is intended to enable appropriate management on construction site and will be able to be applied effectively to a variable construction site. It can also be used in all fields of construction management.