• Corrosion Science and Technology
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• v.16 no.5
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• pp.241-246
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• 2017

The comparative results of corrosion testing in humid tropical atmosphere in rural and coastal areas for hot dipped zinc coatings are presented below. The test was conducted in outdoor conditions over a period of five years. The mass loss and other performance characteristics of two types of zinc coatings were evaluated, analysed and discussed in relation to the climatic and environmental parameters. The corrosion rates of the coatings exposed to coastal conditions were about three times higher than the corrosion rates appreciated in rural conditions. The data demonstrates that the corrosion process obeys an equation of the form $M=At^n$, where M is the loss of metal and t is the time of exposure. A and n are constants which values depend on the environmental characteristics and the physicochemical behavior of the corrosion products respectively. Corrosion is strongly influenced by atmospheric time of wetness (TOW) and airborne salinity. The nature and composition of corrosion products are also considered. Simonkolleite, a major crystalline phase, was found in the zinc corrosion products exposed to coastal conditions, while zinc hydroxide and zinc hydrosulfate are easily found in rural settings.

• Journal of the Korean Society of Clothing and Textiles
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• v.48 no.3
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• pp.501-510
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• 2024

This study aimed to compare the cooling effect of specific body parts to increase workers' thermal comfort. The parts to be cooled comprised the head and neck; the coolant was a phase change material. The participants were ten men in their 20s of average size according to the 8th Size Korea. The experiment was conducted under the following conditions: 28.0 ± 0.5℃, 60.0 ± 5.0% RH, and 0.2 ± 0.1m/s. The exercise consisted of participants moving for 15 min at a constant speed of 80 BPM; later, a subjective sensation was performed, and the clothing surface temperature was measured. In doing so, heat, wetness, and discomfort after exercise were confirmed to have increased without a coolant. Significant differences over time appeared only when no coolant was used, showing that thermal comfort decreased. Despite the addition of coolant, the clothing surface temperature gradually increased over time, but it decreased with coolant rather than without it. Therefore, additional coolant areas, a lower temperature, and simultaneous cooling convection were required to improve thermal comfort.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.41-41
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• 1995

In order to discuss the differences among the SMP(Surface Moisture Availability Parameter), by previous researchers on the basis of their own theoretical and empirical background, we assessed the SMP according to the soil types and volumetric soil water contents. The results are as follows. There are differences among all the five SMAPs. There''s a tendency that the larger grain size, the higher value of parameters. And they divided into two groups for their value: one group has parameters with exponential function and the other with cosine and linear function. The maximum difference between the two groups appears when the volumetric soil water contents are 0.07$m^3m^{-3}$ for sand, 0.l1$m^3m^{-3}$ for loam, 0.12 for clay, and 0.13$m^3m^{-3}$ for silt loam. So, these differences must be considered when we estimate the surface evaporation rate. From field data, the paddy field soil around Junam reservoir is classified as a silt has high wetness, 0.56. So, the parameter obtained from the field measurement is much higher than that of Clapp and Hornberger(1978)''s Table. This study treated the SMP for a certain point of time in winter season. But if we measured the soil water contents continuously, we could obtain better time-dependent parameter.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.206-214
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• 2005

Heterogeneously-catalyzed oxidation of aqueous phase trichloroethylene (TCE) over supported metal oxides has been conducted to establish an approach to eliminate ppm levels of organic compounds in water. A continuous flow reactor system was designed to effect predominant reaction parameters in determining catalytic activity of the catalysts for wet TCE decomposition as a model reaction. 5 wt.% $CoO_x/TiO_2$ catalyst exhibited a transient period in activity vs. on-stream time behavior, suggesting that the surface structure of the $CoO_x$ might be altered with on-stream hours; regardless, it is probable to be the most promising catalyst. Not only could the bare support be inactive for the wet decomposition reaction at $36^{\circ}C$, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Very low TCE conversion appeared for $TiO_2$-supported $NiO_x$ and $CrO_x$ catalysts. Wet oxidation performance of supported Cu and Fe catalysts, obtained through an incipient wetness and ion exchange technique, was dependent primarily on the kinds of the metal oxides, in addition to the acidic solid supports and the preparation routes. 5 wt.% $FeO_x/TiO_2$ catalyst gave no activity in the oxidation reaction at $36^{\circ}C$, while 1.2 wt.% Fe-MFI was active for the wet decomposition depending on time on-stream. The noticeable difference in activity of the both catalysts suggests that the Fe oxidation states involved to catalytic redox cycle during the course of reaction play a significant role in catalyzing the wet decomposition as well as in maintaining the time on-stream activity. Based on the results of different $CoO_x$ loadings and reaction temperatures for the decomposition reaction at $36^{\circ}C$ with $CoO_x/TiO_2$, the catalyst possessed an optimal $CoO_x$ amount at which higher reaction temperatures facilitated the catalytic TCE conversion. Small amounts of the active ingredient could be dissolved by acidic leaching but such a process gave no appreciable activity loss of the $CoO_x$ catalyst.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.427-435
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• 1995

In order to discuss the differences among the SMP(Surface Moisture Availability Parameter), by previous researchers on the basis of their own theoretical and empirical background, we assessed the SMP according to the soil types and volumetric soil water contents. The results are as follows. There are differences among all the five SMAPs. There's a tendency that the larger grain size, the higher value of parameters. And they divided into two groups for their value: one group has parameters with exponential function and the other with cosine and linear function. The maximum difference between the two groups appears when the volumetric soil water contents are 0.07m3m-3 for sand, 0.l1m3m-3 for loam, 0.12 for clay, and 0.13m3m-3 for silt loam. So, these differences must be considered when we estimate the surface evaporation rate. From field data, the paddy field soil around Junam reservoir is classified as a silt has high wetness, 0.56. So, the parameter obtained from the field measurement is much higher than that of Clapp and Hornberger(1978)'s Table. This study treated the SMP for a certain point of time in winter season. But if we measured the soil water contents continuously, we could obtain better time-dependent parameter. Key words : SMAP(Surface Moisture Availability Parameter), Paddy field, Volumetric soil water content, Evaporation, Capillary potential.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.327-335
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• 2020

The method of selecting an existing flood hazard area via a numerical model requires considerable time and effort. In this regard, this study proposes a method for selecting flood vulnerable areas through topographic analysis based on a surface runoff mechanism to reduce the time and effort required. Flood vulnerable areas based on runoff mechanisms refer to those areas that are advantageous in terms of the flow accumulation characteristics of rainfall-runoff water at the surface, and they generally include lowlands, mild slopes, and rivers. For the analysis, a digital topographic map of the target area (Seoul) was employed. In addition, in the topographic analysis, eight topographic factors were considered, namely, the elevation, slope, profile and plan curvature, topographic wetness index (TWI), stream power index, and the distances from rivers and manholes. Moreover, receiver operating characteristic analysis was conducted between the topographic factors and actual inundation trace data. The results revealed that four topographic factors, namely, elevation, slope, TWI, and distance from manholes, explained the flooded area well. Thus, when a flood vulnerable area is selected, the prioritization method for various factors as proposed in this study can simplify the topographical analytical factors that contribute to flooding.

• Journal of the East Asian Society of Dietary Life
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• v.12 no.2
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• pp.141-153
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• 2002

Water activity of sausage added Umbelliferaeceae wild plants powder was decreased as storage time was prolonged and all samples were lower than those of the control. During the storage period, pH values of all samples were decreased. Cooking loss and storage loss was decreased as storage time was prolonged and showed differential from added sample. L, a, b values had a tendency to decrease, during the storage period. As the percentage of the wild plants powder in sausage, L, a values were decreased and b value was increased. Total plate counts of bacteria were increased as storage time was prolonged and wild plants powder added sausages were lower than control. Coriander 3.0% added sausage was the lowest total plate counts of bacteria, 1.3$\times$10$^{6}$ at four week'storage. As the percentage of wild plants powder in sausage was increased, total plate counts of bacteria decreased. Springiness, cohesiveness, chewiness, gumminess and hardness value of all sample were increased or decreased as storage time was longer. But they did not showed greatest various with storage time as well as additives. The sensory score of wild plants powder 0.5% added sausage were the highest, but wild plants powder 3.0% added sausage were the lowest. All the sensory score of coriander added sausage were high. The sensory score of all sample were decreased as storage time was prolonged. In wild plants powder 3.0% added sausage, the relationship between color, flavor, chewiness, wetness, taste and overall of sensory evaluation and all item of the textural characteristic showed huh correlation score. When storaging sausage for two weeks, the correlation of relationship between hardness of sensory evaluation and chewiness of textural characteristic was high.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.3
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• pp.47-53
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• 2001

When a ship advancing in waves is subjected to impact forces or irregular forces, the motion analyses for ship are convenient for being calculated in the time domain. The added mass, wave damping coefficients, wave exciting forces and mean drift forces are calculated by 3-Dimensional panel method used the translating pulsating Green function in the frequency domain and the motion equations which are considered by the memory effect due to waves are numerically solved by using the Newmark-$\beta$ method in the time domain. The motion analyses are carried out for a Series 60($C_B=0.7$) moving in irregular waves. The items of calculation are 6-degree motions, accelerations at the fore and after position, numbers of deck wetness and numbers of exposure at ship-bottom, etc. Moreover, the thrust addition in waves is examined by considering the time mean drift forces in the motion equations of time domain.

• Journal of Haehwa Medicine
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• v.8 no.2
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• pp.245-257
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• 2000

A clinical study was done 40 patients of chronic prostatitis who was treated in Dept. of Internal Medicine, Oriental Medicine Hospital, Taejon University, from 1 Mar. 1999 to 31 Oct. 1999. The results were as follows. 1. In distribution of age, 30's and 40's were 57.5% the most, 20's and 60's were 35.0%, 50's was 7.5%. 2. In distribution of past history, the urethritis(45.0%) was the most. 3. In distribution of ocupation, a white-collar worker was 35.0%, a business man was 22.5%, a public servant was 12.5%, etc. 4. Sitting the mean time of day were distributed 5~7 hours, above 7 hours, 3~5 hours, under 3 hours, etc. 5. The resting interval of a long distance drive were distributed 2 hours(35.0%), 3 hours(32.5%), etc. 6. The habit of enduring ejaculation during sexual intercourse was showed 45.0%. 7. The habit of enduring urination was showed 20.0%. 8. Influency of mental stress was showed 90.0%. 9. Ten cases(25.0%) were showed riding horse or riding bicycle. 10. Four cases(10.0%) were showed wearing tight trousers. 11. The habit of put a wallet his hip pocket was showed 57.5%. 12. The most common symptom was distributed the others symp-tom(66.8%) and the voiding symptom(63.3%) more than pain-neuro-logical symptom(37.5%) and symptom related with sexual function (26.6%). 13. In distribution of palpation, lower abdominal pain, lumbar pain, perineal or parascrotal pain were mostly showed right side. Moreover diagnosis of pulsation was weakly showed chi pulse of right. 14. Duration of disease were distributed above 1 year(82.5%), under 1 year(17.5%). Degree of prostatitis was severe showed adove 1 year. 15. The distribution of WBC count of the prostatic secretion, com-paring with before therapy and after therapy, were showed from 5 cases to 0 case in very many/HPF, from 23 cases to 13 cases in many/HPF, from 12 cases to 13 cases in 10~30/HPF, from 0 case to 13 cases in under 10/HPF. 16. Therapeutic improvement of symptom were distributed pain-neurological symptom(94.8%), the others symptom(90.8%), the void-ing symptom(89.6%) and symptom related with sexual function(67.5%). 17. Differentiation of symptoms and signs were distributed dificiency of spleen-lung vital energy, wetness-heat of lower warmer, dificiency of spleen-kidney yang, dificiency of kidney yin, wetness-phlegm, dificiency of vital energy and blood. The prescriptions were Bojungikgitang(44.6%), Yukmijihwangtang(20.7%), Palmijihwangtang(12.0%), etc.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.743-748
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• 2006

Ren et al. analyzed the performance of the indirect evaporative cooler according to the direction of the flow considering evaporation water flow and wetness. However the effect of NTU of each channel on the performance of the indirect evaporative cooler according to the direction of the flow was not analyzed exactly. In this study the effect of the direction of the flow on the Indirect evaporative cooling performance changing NTU of each channel are investigated theoretically. The cooling process of the indirect evaporative cooler by flow direction is modeled into a set of linear differential equations and solved to obtain the exact solutions to the temperatures of the hot fluid, the moist air, and evaporation water. Based on the exact solution in the case of different NTU of each channel, we study the change of the distribution of the temperature according to each flow direction and at the same time analyze the effect of the flow direction on the cooling performance.