• The Korean Journal of Community Living Science
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• v.18 no.4
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• pp.681-686
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• 2007

This study was conducted to investigate the effects of the thermally different states of human feet on temperature regulation in winter season. Five healthy female students of age 20 volunteered as subjects to participate in the study. Physiological responses such as rectal temperature and skin temperatures as well as subjective responses of thermal comfort and thermal sensation were observed. Preferred clothing and preferred temperature were also evaluated in terms of behavioral temperature regulation. The results obtained through the experiment were statistically analyzed using paired t test. Rectal temperature was decreased greater (p<.01) and mean skin temperature was maintained higher (p<.01) in feet wanning than in feet cooling. Results of preferred clothing were coincident with those of general thermal sensation. There was a higher tendency to prefer temperature in feet wanning than feet cooling in the morning. It was concluded that keeping feet skin temperature lower in the early morning and higher in the late evening would be effective in terms of regulating circadian rhythm of core temperature.

• Journal of Plant Biotechnology
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• v.45 no.2
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• pp.83-89
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• 2018

The interplay of plant hormones is one of the essential mechanisms for plant growth and development. A recent study reported that Brassinosteroids (BR) and ABSCISIC ACID (ABA) interact antagonistically in early seedling developments through the BR-mediated epigenetic repression of ABSCISIC ACID-INSENSITIVE 3 (ABI3). However, the other physiological roles of the BR-mediated regulation of ABI3 and ABA responses beyond early seedling developments remain largely unknown. Here, we showed that the activation of BR signaling by high temperatures promotes flowering time through the suppression of ABI3 expressions. Elevated ambient temperature induced early flowering in wild type Col-0 plants, but not in BR-defective bri1-116 mutant plants. Conversely, a hyper BR biosynthetic dwf4-D mutant displayed more sensitive thermomorphic long shoot elongation and early flowering. Both expression patterns and physiological responses supported the biological roles of ABI3 in the regulation of floral transition and reproduction under high temperature conditions. Finally, we confirmed that the lowered expressions of the transcript and protein levels of ABI3 brought on by elevated temperature were correlated with warmth-induced early flowering phenotypes. In conclusion, our data suggest that the BR- and warmth-mediated regulation of ABI3 are important in thermomorphic reproductive phase transitions in plants.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05b
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• pp.124-127
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• 2002

A CMOS voltage regulation circuit for use at low-voltage is proposed. Circuits for a positive and for a negative current regulation are presented and are designed with commercial CMOS technology. The voltage regulation that is stable over ambient temperature variations is an important component of most data acquisition systems. These results are verified by the H-SPICE simulation $0.8{\mu}m$ parameter. As the result, the temperature dependency of output voltage is $0.57mV/^{\circ}C$ and the power dissipation is 1.8 mV on 5V supply voltage.

• Journal of Power System Engineering
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• v.18 no.6
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• pp.77-83
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• 2014

As the interest on the air pollution is gradually risen up at home and abroad, their vehicle emission regulations have been reinforcing by steps. PM regulation was also reinforced 4times for the last 13years and has been applied to SI vehicles after EURO 5. Additionally, knowing that small particles of PM can easily penetrate deep into lungs PM number was added on the regulation from EURO5+ and is applied to CI vehicles. Also, PN regulation is going to be applied to SI vehicles. But, because the regulation is appled to only a general test mode of each countries that is performed at $25{\pm}5^{\circ}C$, it is unclear whether the regulation can work on the other ambient temperature conditions or not. In this paper, to know that exhaust emission characteristics at the special conditions CI vehicles(CRDi w, w/o DPF) were tested using 5-cycle mode, NEDC mode at 5-ambient temperatures (35, 25, 0, -7 and -15) and the exhaust emission test results were discussed. The results show that the vehicle with DPF emits much low PM(and PM number) on all of the test mode. However, NOx of the other mode was emitted higher than regulation mode. Also. NOx was sharply increased according to decreasing Ambient Temperature.

• Computers and Concrete
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• v.19 no.6
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• pp.659-666
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• 2017

Based on the Arrhenius equations, several hydration exothermic models that precisely calculate the influence of concrete's self-temperature duration on its hydration exothermic rate have been presented. However, the models' convergence is difficult to achieve when applied to engineering projects, especially when the activation energy of the Arrhenius equation is precisely considered. Thus, the models' convergence performance should be improved. To solve this problem and apply the model to engineering projects, the relationship between fast iteration and proper expression forms of the adiabatic temperature rise, the coupling relationship between the pipe-cooling and hydration exothermic models, and the influence of concrete's self-temperature duration on its mechanical properties were studied. Based on these results, the rapid convergence of the hydration exothermic model and its coupling with pipe-cooling models were achieved. The calculation results for a particular engineering project show that the improved concrete hydration exothermic model and the corresponding mechanical model can be suitably applied to engineering projects.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.8
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• pp.1033-1038
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• 2014

Electric vehicles should be connected to power system for charge and discharge of battery. Besides vehicle's battery is charged for a power source, it is also reversibly possible to provide power source from battery to power system. Researches on battery usage for regulation resources have been progressed and could cause cost increase excessively because they distribute regulation capacity equally without considering the battery wear cost of SOC, temperature, voltage and so on. This causes increase of grid maintenance cost and aggravate economical efficiency. In this paper it is studied that the cost could be minimized according to the battery condition and characteristic. The equation is developed in this paper to calculate the possible number of charge and discharge cycle, according to SOC level and weighting factors representing the relation between battery life and temperature as well as voltage. Thereafter, the correlation is inferred between the battery condition and wear cost reflecting the battery price, and the expense of compensation is decided according to the condition on battery wear-out of vehicle. In addition, using realtime error between load and load expectation, it is calculated how much regulation capacity should be provided.

• Journal of the Korean Institute of Gas
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• v.18 no.2
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• pp.28-34
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• 2014

In the natural gas pressure regulation station, high pressure natural gas is decompressing using pressure regulation valves. Waste pressure occurred in the pressure regulation process can be recovered through adopting turbo expanders. However, in the waste pressure recovery process, Joule Thompson effect causes below $0^{\circ}C$ and this low temperature freezes outside land of pipeline or generates methane hydrate in the pipeline which can block the pipeline. Therefore, turbo expander systems are accompanying with a boiler for preheating natural gas. Molten carbonate fuel cell (MCFC), one of the high temperature fuel cell, can use natural gas as a direct fuel and is also exhausting low emission gas and generating electricity. In this paper, a thermodynamic analysis on the hybrid MCFC-turbo expander system is conducted. The fuel cell system is analyzed for the base load of the hybrid system.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.2
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• pp.199-204
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• 2000

This study was conducted to investigate the thermoregulatory responses and wearing behavior of the cold-sensitive men when exposed to the mild cold of 14$^{\circ}C$. Two sessions of experiment were carried out and five healthy young men for the cold-sensitive group(CSG) and four healthy young for the cold-insensitive group(CIG) participated in the study as subjects CSG maintained rectal temperature lower than CIG due to their thicker clothing resulted in larger decrease of rectal temperature. CSG maintained skin temperatures higher than CIG. CSG felt cooler than CIG but wore thicker clothing for thermal comfort and this made keep their sensation warmer. These results were discussed in terms of autonomic and behavioral temperature regulation.

• Journal of IKEEE
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• v.18 no.1
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• pp.37-44
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• 2014

In this paper we present an LDO based on an error amplifier. The designed error amplifier has a gain of 89.93dB at low frequencies. This amplifier's Bandwidth is 50.8MHz and its phase margin is $59.2^{\circ}C$. Also we proposed a BGR. This BGR has a low output variation with temperature and its PSRR at 1 KHz is -71.5dB. For a temperature variation from $-40^{\circ}C$ to $125^{\circ}C$ we have just 9.4mV variation in 3.3V LDO output. Also it is stable for a wide range of output load currents [0-200mA] and a $1{\mu}F$ output capacitor and its line regulation and especially load regulation is very small comparing other papers. The PSRR of proposed LDO is -61.16dB at 1 KHz. Also we designed it for several output voltages by using a ladder of resistors, transmission gates and a decoder. Low power consumption is the other superiority of this LDO which is just 1.55mW in full load. The circuit was designed in $0.35{\mu}m$ CMOS process.

• Journal of Power System Engineering
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• v.12 no.5
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• pp.34-39
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• 2008

The combustion purpose of diesel engine is to reduce the emission of green gas and to produce high output. Generally, the regulation matter of emission gas is largely diveded by 'THC', 'NOx', 'CO' and 'PM'. Among those matters, the most problem is to disgorge into 'PM', the character of diesel combustion. Diesel PM can be controlled using Diesel Particulate Filter, which can effectively reduce the level of soot emissions to ambient background levels. $NO_2$ generated by the DOC is used to combust the carbon collected in the DPF at low temperature. To certificate DPF device that is suitable to domestic circumstances, it is necessary to exactly evaluate the DPF devices according to the regulation of DPF certificate test procedure fur retrofit. To do carry out the above-mentioned description the understanding of that regulation like the standard of PM reduction is needed. In this study the test procedure including test cycle and BPT test condition was examined, and also the test result for specific DPF was analyzed. In every test like field test, PM reduction efficiency test and Seoul-10 mode test, no defect was showed.