• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.4
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• pp.121-129
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• 2001

The semi-adiabatic temperature rise and the losses of temperature of cement paste, mortar and concrete were measured by an apparatus of semi-adiabatic temperature. Heat of hydration was measured by a conduction calorimeter and adiabatic temperature rise of concrete was measured by an adiabatic calorimeter. The derived equation which can assume the adiabatic temperature was proposed by measuring the semi-adiabatic temperature of concrete. The maximum adiabatic temperature rise of concrete obtained by the derived equation of adiabatic temperature, $T_{ad}(t)=T_{sad}(t)+T_{dis}(t)$, showed $55^{\circ}C$ approximately and it had good relation with the other one obtained by the heat of hydration of cement paste and with maximum value which was measured by the adiabatic calorimeter. The adiabatic temperature rise obtained by derived equation was a different information in comparison with the value obtained by adiabatic temperature rise equations by Hell and et. al. in early age, but it showed similar tendencies with the other one according to elapsed time. Adiabatic temperature rise of lich mix concrete with highly cement content was predicted. The adiabatic temperature rise of cement paste and mortar obtained by derived equation from us showed comparatively matching results to compared with that of obtained by adiabatic temperature equation from concrete standard specification.

• ETRI Journal
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• v.26 no.6
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• pp.513-519
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• 2004

This paper presents a low power 16-bit adiabatic reduced instruction set computer (RISC) microprocessor with efficient charge recovery logic (ECRL) registers. The processor consists of registers, a control block, a register file, a program counter, and an arithmetic and logical unit (ALU). Adiabatic circuits based on ECRL are designed using a $0.35{\mu}m$ CMOS technology. An adiabatic latch based on ECRL is proposed for signal interfaces for the first time, and an efficient four-phase supply clock generator is designed to provide power for the adiabatic processor. A static CMOS processor with the same architecture is designed to compare the energy consumption of adiabatic and non-adiabatic microprocessors. Simulation results show that the power consumption of the adiabatic microprocessor is about 1/3 compared to that of the static CMOS microprocessor.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.3
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• pp.656-663
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• 1990

To investigate the optimum design conditions of Stirling Engines at the preliminary design stage, comparative study between adoabatoc analysis based on an approximate analytical solution to the Ideal Adiabatic Model and the existing isothermal analysis has been carried out. The optimum phase angle obtained from adiabatic analysis to achieve the maximum work with given combination of design parameters is greater than that from isothermal analysis, while the optimum swept volume ratio is smaller. Effect of variation in the temperature ratio on the work parameter is proved to be stronger in adiabatic analysis. On the contrary, the work parameter by adiabatic analysis is less sensitive to a change in the dead volume ratio. Especially in adiabatic analysis there exists the optimum dead volume ratio maximizing the work parameter, which may provide a lower limit of it. Considering that the adiabatic model is more reasonable, signifiant differences between two methods lead to the conclusion that adiabatic analysis is preferable to isothermal one for the preliminary design of Stirling Engines.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1563-1566
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• 2002

A 16-bit adiabatic datapath for micro-power RISC processor is designed. The datapath is composed of a 3-read and 1-write multi-port adiabatic register file and an arithmetic and logic unit. A four-phase clock generator is also designed to provide supply clocks fer adiabatic circuits and the driving capability control scheme is proposed. All the clock line charge on the capacitive interconnections is recovered to recycle energy. Adiabatic circuits are designed based on efficient charge recovery logic(ECRL) and are implemented using a 0.35 fm CMOS technology. Functional and energy simulation is carried out to show the feasibility of adiabatic datapath. Simulation results show that the power consumption of the adiabatic datapath including supply clock generator is reduced by a factor of 1.4∼1.5 compared to that of the conventional CMOS.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.6
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• pp.537-544
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• 2008

In this paper, flow characteristics of an adiabatic capillary tube in a transcritical $CO_2$ have been investigated employing the homogeneous model. The model is based on fundamental equations of mass, energy and momentum which are solved simultaneously. Two friction factors(Churchill) and viscosity(McAdams) are comparatively used to investigate the flow characteristics. Supercritical and subcritical thermodynamic and transport properties of $CO_2$ are calculated employing EES property code. Flow characteristics analysis of $CO_2$ adiabatic capillary tube is presented to offer the basic design data for the operating parameters. The operating parameters considered in this study include inlet temperature and pressure of an adiabatic capillary tube, evaporating temperature and inner diameter tube. The main results were summarized as follows : inlet temperature and pressure of an adiabatic capillary tube, evaporating temperature, mass flowrate and inner diameter of $CO_2$ adiabatic capillary tube have an effect on length of an adiabatic capillary tube.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.624-629
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• 2001

An experimental study was performed to investigate adiabatic wall temperature and heat transfer coefficient around on a module with longitudinal fin heat sink cooled by forced air flow. In the first method, inlet air flow(1-7m/s) and input power(3-5W) was varied after a heated module were placed on an adiabatic floor($320{\times}550{\times}1mm^{3}$). An adiabatic wall temperature was determinated to use liquid crystal film(LCF). In the second method to determinate heat transfer coefficient, inlet air flow(1-7m/s) and the heat flux of rubber heater($0.031-0.062\;W/cm^{2}$) was varied after an adiabatic module was placed on rubber heater covering up an adiabatic floor. In addition, surface oil-film visualization were performed to characterize the macroscopic flow-field around a module.

• JSTS:Journal of Semiconductor Technology and Science
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• v.3 no.4
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• pp.194-198
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• 2003

A 16-bit adiabatic low-power Micro-processor core is designed. The processor consists of control block, multi-port register file and ALU. A simplified four-phase clock generator is designed to provide supply clocks for adiabatic processor. All the clock line charge on the capacitive interconnections is recovered to recycle the energy. Adiabatic circuits are designed based on ECRL(efficient charge recovery logic) and $0.35\mu\textrm$ CMOS technology is used. Simulation results show that the power consumption of the adiabatic Microprocessor core is reduced by a factor of 2.9~3.1 compared to that of conventional CMOS Microprocessor

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.5
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• pp.1134-1143
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• 1994

A study of adiabatic shear band formation and propagation of 4340 steel was done using the stepped speciment which was subjected to high velocity impact. The high velocity impact was performed on compression Hopkinson bar impact machine. After the controlled impact, the specimen was prepared for visual inspection. Numerical simulation was also performed with same geometrical dimension using explicit time integration finite element code. Experimental results were then compared with the numerical prediction. It was found that the numerical prediction is quite accurate, average thickness of adiabatic shear band is about $10{\mu}m$, the macro crack around shoulder is due to folding, and the deformation control ring is effective to freeze the propagation of adiabatic shear band.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.949-951
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• 2000

In order to design thermally trigger controlled persistent current switch(PCS) for MRI magnet system, it is very important to know informations of applied adiabatic method and condition to get designed resistance and characteristics. Adiabatic part of PCS is consist of cotton-gummed tape and cryogenic stycast. This adiabatic method has the advantage of continuously winding superconducting and adiabatic part of PCS and reducing the time of manufacture. We experimentally derived averaged thermal conductivity on the assumption that shape of adiabatic part of PCS is that of pipe. In result, averaged thermal conductivity is about 0.29 W/m K and designed value is very satisfied with actual experimental data.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.51-52
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• 2013

Generally, Adiabatic temperature rise and temperature rise rate are reported to increases when placement temperature, W/B and the unit water content is fixed. In this study, properties of adiabatic temperature rise on placement temperature consider the hot weather environments from of W/B 0.29, 0.34, 0.40 was reviewed, the amount of cement on mixing condition of the same W/B and unit water content evaluated on the impact of the adiabatic temperature rise. As a results, the adiabatic temperature rise of concrete is proportionate to binder as well as the cement content under the same unit water content.