• Asian-Australasian Journal of Animal Sciences
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• v.30 no.11
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• pp.1598-1604
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• 2017

Objective: The present study investigated the litter performance of multiparous sows fed 3% and 6% densified diets at farrowing to weaning during summer with mean maximum room temperature of $30.5^{\circ}C$. Methods: A total of 60 crossbred multiparous sows were allotted to one of three treatments based on body weight according to a completely randomized design. Three different nutrient levels based on NRC were applied as standard diet (ST; metabolizable energy, 3,300 kcal/kg), high nutrient level 1 (HE1; ST+3% higher energy and 16.59% protein) and high nutrient level 2 (HE2; ST+6% higher energy and 17.04% protein). Results: There was no variation in the body weight change. However, backfat thickness change tended to reduce in HE1 in comparison to ST treatment. Dietary treatments had no effects on feed intake, daily energy intake and weaning-to-estrus interval in lactating sows. Litter size, litter weight at weaning and average daily gain of piglets were significantly greater in sows in HE1 compared with ST, however, no difference was observed between HE2 and ST. Increasing the nutrient levels had no effects on the blood urea nitrogen, glucose, triglyceride, and creatinine at post-farrowing and weaning time. The concentration of follicle stimulating hormone, cortisol and insulin were not affected by dietary treatments either in post-farrowing or weaning time. The concentration of blood luteinizing hormone of sows in ST treatment was numerically less than sows in HE2 treatment at weaning. Milk and colostrum compositions such as protein, fat and lactose were not affected by the treatments. Conclusion: An energy level of 3,400 kcal/kg (14.23 MJ/kg) with 166 g/kg crude protein is suggested as the optimal level of dietary nutrients for heat stressed lactating sows with significant beneficial effects on litter size.

• Journal of Welding and Joining
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• v.35 no.3
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• pp.68-74
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• 2017

Characteristics of dissimilar metal welds between alloy steel ASTM A387 Gr. 91 and carbon steel ASTM A516 Gr.70 made with Flux cored arc welding(FCAW) have been evaluated in terms of microstructure, mechanical strength, chemical analysis by EDS as well as corrosion test. Three heat inputs of 15.0, 22.5, 30.0kJ/cm were employed to make joints of dissimilar metals with E71T-1C wire. Post-weld heat treatment was carried out at $750^{\circ}C$ for 2.5 h. Based on microstructural examination, Intragranular polygonal ferrite and grainboundary ferrite were formed only in first layer of weld metal. Another layers consisted of acicular ferrite and $Widmannst{\ddot{a}}tten$ ferrite. The amount of acicular ferrite was increased with decreasing heat input and layer. Heat affected zone of alloy steel showed the highest hardness due to the formation of tempered martensite and lower bainite. Lower and upper bainite were formed in heat affected zone of carbon steel. Tensile strengths of dissimilar metal welds decreased with increasing heat inputs. Dissimilar metal welds showed a good hot cracking resistance due to the low HCS index below 4. The salt spray test of dissimilar metals welds showed that the weight loss rate by corrosion below 170 hours was decreased with increasing heat inputs due to the increase of the amount of acicular ferrite.

• Restorative Dentistry and Endodontics
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• v.46 no.1
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• pp.6.1-6.10
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• 2021

Objectives: The aim of this study was to evaluate the corrosion resistance of heat-treated (Reciproc and WaveOne) and non-heat-treated (ProTaper and Mtwo) superelastic nickel-titanium endodontic files when immersed in a 5.25% sodium hypochlorite solution. Materials and Methods: Anodic polarization curves were obtained with potential sweeps that began at the open circuit potential or corrosion potential (E_corr). The pitting potential (E_pit) was identified on the anodic polarization curve as the potential at which a sudden increase in current was observed. The micromorphology of the 28 tested files was analyzed before and after the electrochemical assay using scanning electron microscope (SEM). The data were analyzed using 1-way analysis of variance with the post hoc Bonferroni test (for E_corr) and the Student t-test for independent samples (for E_pit). Results: The mean E_corr values were 0.506 V for ProTaper, 0.348 V for Mtwo, 0.542 V for Reciproc, and 0.321 V for WaveOne files. Only WaveOne and Protaper files exhibited pitting corrosion, with E_pit values of 0.879 V and 0.904 V, respectively. On the SEM images of the ProTaper and WaveOne files, cavities suggestive of pitting corrosion were detected. Conclusions: Signs of corrosion were observed in both heat-treated and non-heat-treated files. Of the evaluated files, WaveOne (a heat-treated file) and ProTaper (a non-heat-treated file) exhibited the lowest corrosion resistance.

• Journal of Dairy Science and Biotechnology
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• v.22 no.1
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• pp.27-35
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• 2004

The shelf lift of market milk should be determined based on the flavor which is influenced by environmental and sanitary conditions of dairy farm, milk processing plant, and storage and transportation facility as well as compositional quality, such as protein and fat, of the milk itself. The legal shelf life of market milk is often limited by microbiological quality, e.g. total bacterial count, coliform count, and food poisoning bacteria. The bacteria involved with milk spoilage and poisoning are originated from bacteria contaminating milk after pasteurization or spores surviving the heat treatment of pasteurization. The important factors which influence the shelf life of market milk are microbiological quality of raw milk, pasteurization condition, post-pasteurization contamination, and temperature during storage and transportation. The organoleptic quality and shelf life of market milk should be further improved by satisfying the consumer's taste, which depends on somatic cell count and bacterial count of milk, feed quality, foreign substance in milk, and physical treatment during processing and transportation.

• Journal of Aquaculture
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• v.12 no.3
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• pp.167-173
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• 1999

Blocking the 1st mitotic cleavage was performed in mud loach (Misgurmus mizolepis) using UV-irradiated cyprinid loach (M. anguillicaudatus) sperm and ternal shocks Optimum UV range for inactivation of cyprinid loach sperm and thermal shocks. Optimum UV range for inactivation of cyprinid loach sperm was between 3,150 to 4,050 ergs/m$m^2$. Heat shock treatment ($41^{\circ}C$ for 3mins) with various treatment initiation times ranged from 22 to 50 min post insemination resulted wide range of success for induced gynogenesis. Best result was obtained when haploid egges were shocked at 28 min after insemination (corresponding to metaphase division of the 1st cleavage); 26% of total eggs inseminated were viable diploid gynogens. The hatching success and early survival of the both meiotic and mitotic gynogenetic groups were significantly lower than those of control crosses (P<0.05). Maternal origin of induced gynogenetic mud loach was verified by multi-locus DNA fingerprinting.

• Journal of Power System Engineering
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• v.7 no.3
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• pp.18-22
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• 2003

A Study has been made to investigate the effects of hot isostatic press(HIP) and post-HIP heat treatment on microstructures and mechanical properties of Ni-based single crystal superalloy CMSX-4. HIP process was found to heal and close micropores significantly, but did not affect the morphologies of. The elimination of as-cast micropores obtained by HIP process resulted in improved stress-rupture lives of Ni-base single crystal superalloy by 185%.

• Journal of Korea Foundry Society
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• v.15 no.5
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• pp.477-482
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• 1995

A computer simulation model of various smelting process for melting waste sand was developed by using energy and material balance concept. This model can predict the coal, flux and oxygen consumption and the volume and temperature of off-gas. The major critical variables for smelting process can be explained by using the analysis of energy and material balance. The major conclusions were as follows; 1. The most important variables for smelting process were high post-combustion ratio, high heat transfer efficiency and refractory protection technology. 2. For saving energy in this smelting process, selection of raw materials i.e coal, flux are very important, espacially using of low volatile coal is very profitable. 3. The treatment cost of waste sand is high and environmental restriction is severe, in this reason we must be concerned in the treatment of waste sand by smelting process.

• Journal of the Korean Applied Science and Technology
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• v.30 no.2
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• pp.362-370
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• 2013

The coconut shell based activated carbon was applied for EDLC (electric double layer capacitor) electrode with the post treatments. The electrochemical properties were evaluated with a coin cell using the activated carbon as electrode. The initial gravimetric and volumetric capacitance of the coconut shell based activated carbon electrode s were 66 F/g and 39 F/cc, and these values decreased to 54 F/g and 32 F/cc after 100 cycles, respectively showing 82% of charge-discharge efficiency. The properties of CV graph with the commercial activated carbon electrodes showed the serious polarization as the result of additional reaction between electrolyte and impurities of the electrode materials. In order to remove impurities efficiently, the commercial activated carbon was treated by alkali and acid solutions consecutively, and then heat treated to control the pore size distribution and the content of surface functional groups. The surface functional groups decreased with the increased heat temperature and the specific capacitance increased with the decreased surface functional groups. The initial capacitance of coconut shell based activated carbon elec trode which was treated with NaOH and HNO3, and then heat treated at $800^{\circ}C$ was 44 F/cc, and the value turned out to be 42 F/cc after 100 cycles, showing over 95% of charge-discharge efficiency.

• 대한공업교육학회지
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• v.31 no.1
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• pp.200-210
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• 2006

This C-ring test, normally employed for evaluating susceptibility to stress-corrosion cracking, was determined to be a suitable small scale test to evaluate PWHT(Post-Weld Heat Treatment) cracking susceptibility. This test is possible to incorporate an actual weld, to introduce a notch into the coarse grained HAZ(Heat Affected Zone), to load the coarse grained HAZ any level of stress ad, most importantly, since the C-ring is an approximately constant strain type test, the stress decreases with time at temperature in a manner similar to that of an actual steel weldment. The procedure employed in making the C-ring was presented in the experimental procedure section, however, several points deserve further discussion. The walls of the weld groove are made along radial lines form the center of th var in order to obtain an HAZ which is oriented perpendicular to the walls of the machined C-ring. Therefore, the plane of maximum stress will be aligned through the HAZ and, therefore, crack propagation will not be forced to deviate form the plane of maximum stress in order to remain in the coarse grained HAZ as is the case with the Y groove test.

• The Journal of the Korea Contents Association
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• v.19 no.7
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• pp.538-545
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• 2019

The purpose of this study was to analyze the change of body temperature and pain by application of Gaussian magnetic for the elderly delayed muscle pain. For the purpose, we selected 15 elderly women(age;$69.47{\pm}1.60$) and conducted repeated experiments. The Gaussian magnetic field area was divided into three areas (1000G, 1500G, 2000G). The applying arbitrarily manufactured magnetic field wristbands changes of body heat and pain before and after wearing Gaussian magnetic were measured and collected data were analyzed using SPSS 19.0. To examine the pre-and post-treatment differences by treatment areas, we conducted paired t-test. Group differences and interaction effects were analyzed using two-way ANOVA and Duncan post hoc tests. The significance level was set to ${\alpha}=.05$. The results are as follows. The change of body heat by the Gaussian magnetic field area showed significant differences in all three groups(P<.05). There were also significant differences in the results of group interactions and in the delayed muscle pain scale between groups(P<.05). The area with the largest difference appeared in the area of 1500G field. The 1000G-1500G Gauss field is considered to be the most ideal magnetic field for body heat and muscle pain changes. In conclusion, the Gaussian magnetic field of 1000G-1500G may affect body temperature and muscle pain in the elderly, and may have a significant impact on the quality of life in old age.