• Journal of Korea Foundry Society
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• v.14 no.6
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• pp.548-557
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• 1994

Grey iron containing a small amount of Cu and Mo to improve the effect of heat treatment and microstructures were poured in to the mold and them austenized at $900^{\circ}C$. After austenitizing the specimens of castings were austempered $210^{\circ}C$, $250^{\circ}C$, $300^{\circ}C$ and $350^{\circ}C$. The effects of matrix structures, mechanical properties and wear characteristics were investigated by austempering temperatures. Tensile strength and hardness of austempered grey iron are increased and the amount of retained austenite is decreased as austempering temperature is lower even though the amount of retained autenite in it only 4%. The amount of rolling wear loss are increased as rolling revolution is increased and wear loss of austempered grey iron under dry rolling condition is characterized by three models; initial wear, stationary wear and abnormal wear. It has been found that the amount of wear loss was increased with increasing maxium compressive stress and rolling revolution.

• Journal of Korean Medical classics
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• v.19 no.4
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• pp.169-181
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• 2006

The Samyang-Sameum(三陽三陰) is the movement form peculiar to the cosmic dual forces. Since Byunggi(病氣) along with the Gyungkki(經氣), The Samyang-Sameum(三陽三陰) is the standard for a diagnosis of a disease's outbreak and change. Anyone of The Samyang-Sameum(三陽三陰) can cause a disease in a Gyungkki(經氣) because each and every human being has different Gyungkki(經氣). And, a disease may outbreak by anyone of Wind-Cold-Warmth-Heat(風寒溫熱). Guiding principles of the six Meridians(六經提綱) is set to diagnose which one of the Gyungkki(經氣) causes a disease. Sanghallon(傷寒論) shows several measures to diagnose the lapse of a disease at the beginning stage of external affection(外感) by Wind-Cold(風寒). It is most serious when the Jeongyung(傳經) symptom appears within 6 to 7 days after a disease outbreak since it indicates the exhaustion of true Eum(眞陰). It means the lapse of a disease that formation of dry stool(燥尸) by fast Jeonsok(轉屬) to Yangmyeong(陽明) after a Taeyang(太陽) is diseased. It also means that a position of disease is worsening by a sticking phase of disease when Yipeum(入陰) symptom after anyone of Samyang-Sameum(三陽三陰) is diseased.

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.3
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• pp.286-297
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• 2010

This study deals with the effect of pretreatment on the $CO_2$ adsorption capacity of zeolitic adsorbents including a commercial A-type zeolite and cation exchanged adsorbents. The pre-heating could change the intrinsic properties such as specific surface area and adsorption capacity of the adsorbent. As a result of the experiment, the moisture previously filled inside might affect the potential adsorption capacity of the adsorbent, and could be disappeared throughout the heat treatment. An optimum pretreatment temperature for the test adsorbent was found to be $400^{\circ}C$, at which temperature enabled more than 90% refreshment. Precise examination through the TPD test showed that the TSA (Temperature Swing Adsorption) process would be desirable in dry adsorption of $CO_2$.

• Computers and Concrete
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• v.12 no.3
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• pp.337-349
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• 2013

Traditional concrete is effectively an insulator in the dry state. However, conductive concrete can attain relatively high conductivity by adding a certain amount of electronically conductive components in the regular concrete matrix. The main purpose of this study is to investigate the electrical and thermal properties of conductive concrete with various graphite contents, specimen dimensions and applied voltages. For this purpose, six different mixtures (the control mixtures and five conductive mixtures with steel fibers of 2% by weight of coarse aggregate and graphite as fine aggregate replacement at the levels of 0%, 5%, 10%, 15% and 20% by weight) were prepared and concrete blocks with two types of dimensions were fabricated. Four test voltage levels, 48 V, 60 V, 110 V, and 220 V, were applied for the electrical and thermal tests. Test results show that the compressive strength of specimens decreases as the amount of graphite increases in concrete. The rising applied voltage decreases electrical resistivity and increases heat of concrete. Meanwhile, higher electrical current and temperature have been obtained in small size specimens than the comparable large size specimens. From the results, it can be concluded that the graphite contents, applied voltage levels, and the specimen dimensions play important roles in electrical and thermal properties of concrete. In addition, the superior electrical and thermal properties have been obtained in the mixture adding 2% steel fibers and 10% graphite.

• Textile Coloration and Finishing
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• v.23 no.4
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• pp.290-297
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• 2011

In this study, the possibility of the practical development of highly sensitive clothing textiles using fibrillated wool fibers were considered by determining the dyeability, the physical and mechanical properties of fibrillated wool fibers treated under strong acid and high temperature ultrasonic wave irradation and they were compared with those of untreated wool fibers. The color strengths of the dyed fibrillated wool fabrics increased by the acid metal complex dyes contrary to the untreated wool fabrics, and color fastness properties to rubbing, light, and dry cleaning were excellent, similar to those of the untreated wool fabrics. The tensile strengths of fibrillated wool fabrics were also kept after the dyeing. Moreover, the Numeri, Fukurami, and THV of the fibrillated wool fabrics were better than those of the untreated wool fabrics.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.620-633
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• 1998

Methods developed for measuring digestibility and availability of amino acids in feedstuffs used in pig nutrition are reviewed. Digestibility is a proportion of an amino acid in a feed that is absorbed from the digestive tract and should be determined from the difference between the amount of amino acid consumed and passing the distal ileum. Techniques for ileal digesta sampling including various types of cannulas: a re-entrant, T-piece, IPV, IPVC and ileaorectal anastomosis are described and comparisons amongst these methods are presented. Other methodologies like mobile bag technique, in vitro assays and mathematical prediction method are also described. Significance and methodologies for measurement of endogenous nitrogen and amino acids losses at the distal ileum and their effect on the apparent and true nitrogen and amino acid digestibilities in feeds are discussed. Factors influencing the apparent and true amino acid digestibilities such as dry matter intake, protein, fibre and antinutritive compounds content in the diet are discussed. Amino acid bioavailability -the proportion of the total amino acid digested and absorbed in a form utilized in metabolism - measured by the growth assay may differ from its ileal digestibility. Chemical methods for determination of available lysine content in heat treated feeds are evaluated.

• Computers and Concrete
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• v.20 no.2
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• pp.119-127
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• 2017

Time-dependent buckling of embedded straight concrete columns armed with Silicon dioxide($SiO_2$) nano-particles exposed to fire is investigated in the present study for the fire time. The column is simulated mathematically with Timoshenko beam model. The governing mass conservation equations to describe heat and moisture transport in concrete containing free water, water vapor, and dry air in conjunction with the conversion of energy are considered. The characteristics of the equivalent composite are determined using Mori-Tanaka approach. The foundation around the column is simulated with spring and shear layer. Employing nonlinear strains-displacements, energy methods and Hamilton's principal, the governing equations are derived. Differential quadrature method (DQM) is used in order to obtain the critical buckling load and critical buckling time of structure. The influences of volume percent of $SiO_2nano-particles$, geometrical parameters, elastic foundation and concrete porosity are investigated on the time-dependent buckling behaviours of structure. Numerical results indicate that reinforcing the concrete column with $SiO_2nano-particles$, the structure becomes stiffer and the critical buckling load and time increase.

• Journal of the Korean Society of Industry Convergence
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• v.19 no.4
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• pp.216-222
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• 2016

Thus, this study aimed to develop a gear-type vane damper in order to replace the link-type vane damper. To achieve this goal, the torque generated in a gear-type vane damper was analyzed, and a structural analysis was conducted. In addition, the fluid flow was analyzed according to the changes in the vane's angle, and experimental tests such as a dry-heat test and cold test were conducted considering the operating conditions of the vessels. Moreover, an appropriate actuator was selected for the developed gear-type vane damper, and studies on the reduction in the backlash due to the facing-pressure adjustment length and flow rate and leakage test due to the vane's angle were conducted.

• Applied Chemistry for Engineering
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• v.8 no.5
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• pp.811-815
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• 1997

The present work describes the effect of dry grinding of a mixture composed of $Y_2O_3$, $BaCO_3$ and CuO powders with a planetary ball mill before heat treatment on crystal structure and superconductivity in the $YBa_2Cu_3O_{7-y}$. The specific surface area of the ground product of mixture decreased with an increase in the grinding time, after showing an upward trend up to 60 minutes of grinding. The critical current density, which was influenced by the grinding time of mixture, indicates the maximum value of about $150A/cm^2$ in the case of 60 minutes grinding, while the critical temperature, which were around 90K, for the sintered bodies were almost independent of the grinding time.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.1
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• pp.11-18
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• 2000

Taegu is notorious as hot and dry summer among Korea cities. One of the most important goals of the open space planning is to ameliorate urban climate of the city. The objective of this research is to evaluate the thermal mitigation effect of the cool islands in Taegu metropolitan city. Cool islands of this paper includes parks and rivers surrounded by or adjacent to urbanized areas. Based on the analysis of the thermal band of Landsat TM at May 17, 1997, the thermal mitigation effect of open spaces in the city could be summarized as follows ; Kumho river showed the largest mitigation effect in terms of the width of mitigation zone and temperature difference. Evaporation from wide water surface and evapo-transpiration from riparian grass land could bring into results. Significant mitigation effect of parks covered with forest can be observed. The temperature range of such parks were between 19.05$^{\circ}C$ and 19.44$^{\circ}C$ However, the thermal mitigation effect of Dalsung park and Apsan park was insignificant. The small size and high percentage of hard paving of the former and the relative low density of the residential areas adjacent to the latter could be the main reason. In conclusion, the thermal mitigation effect in urban ope spaces could be detectedby the employment of thermal band data of Landsat TM and GIS buffering technique.