• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.4
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• pp.108-117
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• 1997

A continuum analysis has been performed for the application to the thermo-elasto-plastic behavior in a discontinuous metal matrix composite. an FEM (Finite Element Method) analysis was implemented to obtain the internal field quantities of composite as well as overall composite behavior and an experiment was demonstrated to compare with the numerical simulation . As the procedure, a reasonably optimized FE mesh generation, the appropriate imposition of boundary condition , and the relevant post processing such as elastoplastic thermomchanical analysis were taken into account. For the numerical illustration, an aligned axisymmetric single fiber model with temperature dependent material properties and precipitation hardening effect has been employed to assess field quantities. It was found that the residual stresses are induced substantially by the temperature drop during the thermal treatment and that the FEM results of the vertically and horizontally constrained model give a good agreement with experimental data.with non-woven carbon mat is about 24% higher than that of composite materials without non-woven carbon mat. Transverse tensile strength and torughness also increase by inserting non-woven carbon mat between layers.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.177-187
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• 2014

Microbial phytases are enzymes with biotechnological interest for the feed industry. In this article, the effect of spray-drying conditions on the stability and activity of extracellular phytase produced by R. microsporus var. microsporus biofilm is described. The phytase was spray-dried in the presence of starch, corn meal (> $150{\mu}m$), soy bean meal (SB), corn meal (< $150{\mu}m$) (CM), and maltodextrin as drying adjuvants. The residual enzyme activity after drying ranged from 10.7% to 60.4%, with SB and CM standing out as stabilizing agents. Water concentration and residual enzyme activity were determined in obtained powders as a function of the drying condition. When exposed to different pH values, the SB and CM products were stable, with residual activity above 50% in the pH range from 4.5 to 8.5 for 60 min. The use of CM as drying adjuvant promoted the best retention of enzymatic activity compared with SB. Spray drying of the R. microsporus var. microsporus phytase using different drying adjuvants showed interesting results, being quite feasible with regards their biotechnological applications, especially for poultry diets.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.2
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• pp.35-42
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• 2008

The compressive residual stress due to shot peening process can increase the intrinsic fatigue strength of surface and therefore would be beneficial in reducing the probability of fatigue damage. However, it was not known that the effect of shot peening on corrosion environment. In this study, the influence of shot peening and corrosion condition on corrosion property was investigated on immersed in 3.5% NaCl, 10% $HNO_3$+3% HF, 6% $FeCl_3$. The immersion test was performed with two kind of specimens. The immersion test periods were carried out on performed 360days. Corrosion potential and weight loss were investigated from experimental results. From these results, the effect of shot peening on the corrosion characteristics was evaluated.

• Journal of Environmental Science International
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• v.11 no.9
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• pp.955-960
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• 2002

The recycled washwater, which has different water quality and is produced about 5 to 20% of the total water volume treated, affects the unit operation of water treatment, especially coagulation process. However, the effects of recycled washwater on unit operation of water treatment have not been fully investigated. In this study, effects of recycled washwater on coagulation process were investigated to find the optimum coagulation condition by analyzing turbidity, $UV_{254}$, TOC removal efficiencies. In addition, effects of recycled washwater on residual Al after coagulation were studied by analyzing soluble and particulate Al. The size distribution and fractal dimension of coagulated also analyzed. The recycled washwater was lower pH than the raw water. And the recycled washwater had higher $UV_{254}$, TOC and residual Al concentration than the raw water. Residual Al concentration of recycled washwater was about 50 times higher than that of raw water. Optimum coagulant dosages on the blending recycled washwater and the raw water for turbidity, $UV_{254}$ and Al removal were lower than that on the raw water. However, TOC removal increased by increasing coagulant dosage. The size and fractal dimension of coagulated particle produced in the blending recycled washwater were larger, which imply faster settling velocity, than those produced in the raw water only.

• Journal of Hydrogen and New Energy
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• v.17 no.3
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• pp.286-292
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• 2006

Chlamydomonas reinhardtii is a green algae that can use light energy and water to produce hydrogen under anaerobic condition. This work reports the effect of limiting factors on hydrogen production in sulfur deprived anaerobic C. reinhardtii culture. In order to confirm the relationship between hydrogen production and limiting factors such as residual PSII activity and endogenic substrate degradation, the increase in chlorophyll concentration and the decrease in starch concentration was investigated during sulfur deprivation. The overall hydrogen production increased depending on cell density in range of $0.4{\sim}0.96\;g$ DCW/l. At this time, the increase in chlorophyll concentration during 24 h after sulfur deprivation increased in proportion to hydrogen production, however, the decrease in starch concentration was not proportional to that. Therefore, hydrogen production under sulfur deprivation using green alga was closely associated with the residual PSII activity than the endogenic substrate degradation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.3
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• pp.31-46
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• 1978

In order to secure the proper use of herbicides that are frequently used in Korea, the behavior of herbicides in various type of soil were studied. This study includes the variation of phytotoxicity, leaching and movement, and residual activity period of herbicides depending upon the type of soil etc. Experiments were also conducted to establish a guideline for the selection of herbicides according to the type of soil and the proper use of each herbicide in various type of soil in Korea. Experimental results showed that the behavior of herbicides could be characterized based on the series or kind of herbicides and devided into two major groups. One group (nitrofen. CNP, benthiocarb and butachlor) of herbicides showed relatively little crop injury and was very dependable. The action of this group was not remarkably influenced by soil components, rainfall and the quantity of herbicide used with the type of soil that had small adsorption capacity such as most of soil in Korea. The other group(simazine, 2, 4-D. linuron, alachlor and simetryne) showed a wide variation in it's action and retained potentially injurious effect. This group was very susceptable to using condition as well as the type of soil itself. Based on the results of various experiments the disappearance of the residual activity period of major herbicides used in upland and paddy field and the related factors were explained. It is believed that the results of this study can be used as a base for the establishment of a guideline for the proper use of each herbicide and can suggest a direction of developing new herbicides.

• Journal of Welding and Joining
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• v.21 no.5
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• pp.568-574
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• 2003

In the welding for the steel structure of H-beam with mild steel and 490N/$\textrm{mm}^2$ high tensile steel, we applied the fillet weld mostly and 6-8mm weld length(AISC-spec.). And a new developed metal-cored-wire is used in automatic welding as well as semi-automatic welding. In this study we have attempted to raise the welding productivity and to stabilize the quality on horizontal positions of fillet welding with the following items: - We improved the weld productivity using metal based cored wire with a high deposition rate in the steel structure of H-beam. - We tested the weldability and evaluated the quality of the weldmetal by horizontal fillet $CO_2$ welding. The process is carried out in combination with a special purpose metal-based FCW with excellent resistance to porosity and high welding speed. - We studied the micro structure of the weldmetal by the various welding conditions. - We studied the effect of welding residual stress by the welding conditions in T-joint. Therefore, it can be assured that more productive and superior quality of the weldmetal can be taken from this study results.

• Journal of Acupuncture Research
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• v.32 no.3
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• pp.197-202
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• 2015

Objectives : The purpose of this study is to report on the residual symptoms after decompression of traumatic compartment syndrome experienced by a patient whose condition was much improved by electroacupuncture and bee venom therapy. Methods : The patient was treated with electroacupuncture and bee venom therapy. The progress of symptoms was checked by visual analog scale, disabilities of the arm, shoulder, and hand(DASH) and range of motion. Results : All results were improved. Scores from the visual analog scale and DASH decreased, while the range of motion increased. Conclusions : Electroacupuncture and bee venom therapy have an effect on residual symptoms after decompression of traumatic compartment syndrome.

• Journal of the Institute of Convergence Signal Processing
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• v.6 no.3
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• pp.143-147
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• 2005

Monitoring and diagnosis of the operating machines are very important for safety operation and maintenance in the industrial fields. These machines are most rotating machines and the diagnosis of the machines has been researched for long time. We can easily see the faulted signal of the rotating machines from the changes of the signals in frequency. The Linear Predictive Coding(LPC) is introduced for signal analysis in frequency domain. In this paper, we propose fault detection and diagnosis method using the Linear Predictive Coding(LPC) and residual signal energy. We applied our method to the induction motors depending on various status of faulted condition and could obtain good results.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.11
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• pp.1061-1066
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• 2006

This paper presents the electrical characteristics with manufacturing process and performance evaluation of high performance zinc oxide varistors. ZnO varistors were fabricated with typical ceramic production methods with different thickness and the structural and electrical characteristics of ZnO varistors were investigated. All varistors exhibited high density, which was in the range of $5.41{\sim}5.49g/cm^3$. In the electrical properties, the reference voltage increased in the range of $4.410{\sim}5.250kV$ with increasing their thickness and the residual voltage exhibited the same trends as the reference voltage. In the long duration current impulse withstand test, E-2 and F-1 samples failed at the two and four shots of impulse current, respectively, but E-1 and F-2 samples survived 18 shots during the test. Before and after this test, the variation ratio of residual voltage of E-1 and F-2 samples were -0.34 % and 0.05 %, respectively, which were in the acceptance range of 5 %. According to the results of tests, it is thought that if the fabrication process such as insulating coating, sintering condition, and soldering method is improved, these ZnO varistors would be possible to apply to the station class arresters in the near future.