• Journal of Haehwa Medicine
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• v.9 no.1
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• pp.461-467
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• 2000

After analyzing the datas to propose the rightful recognition and research direction for the long used charcoal, the following conclusions are obtained. 1. The 'soot' is pure Korean which has the meaning of 'fresh power' and is translated in English as charcoal which is composition of china and cool meaning good. 2. The main dispositions of the charcoal are 85% of carbon, 10% of water, 4% of minerals and 2% of essential so that the understanding of properties and effects of carbon are essential. 3. It is usually appeared that there are purifying and detoxifying effects of the woods and the room in practical use of charcoal. 4. In everyday life, it removes the odors, regulates the humidity and prevents the decaying. 5. It is often used medically for activating liver fuctions, regulating digestive fuctions and for diseases with inflammations, fever or bleeding. 6. The charcoal is used in medical treatment internally as well as externally. Above conclusions shows that the objective research is needed for clinical use considering the physical and chemical properties in future.

• The Journal of Engineering Geology
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• v.34 no.1
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• pp.25-38
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• 2024

Laboratory tests of accelerated artificial weathering compared the effects of seawater and acidified distilled water on rock weathering. The experiments simulated chemical and physical weathering of five different types of volcanic rock by applying 45 freeze-thaw cycles using seawater and acidified distilled water (pH 3), both at 70℃. The physical properties and uniaxial compressive strength (UCS) of the rocks were measured after 15 and 45 cycles of artificial weathering. Most of degradation of physical properties appeared within the first 15 cycles, and acidified distilled water had a greater effect than seawater. Analysis of variance (ANOVA) statistically evaluated the differences in UCS of the different rock types during the tests. The rate of UCS reduction after 45 cycles was similar across the samples, being independent of the rock type and the trend of changes in physical properties. In contrast to the changes in the physical properties, the UCS was more affected by seawater than by acidified distilled water.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.247-247
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• 2006

Chemical and physical synthesis routes were combined to prepare macroporous thin films of semiconducting metal-oxides such as $CaCu_{3}Ti_{4}O_{12}\;and\;TiO_{2}$ by sputtering onto (PMMA) microsphere templated substrates. Subsequently, the colloidal templates were removed by thermal decomposition. The remaining inorganic films comprised a monolayer of hollow hemispheres with diameter commensurate with that of the microspheres. This unique morphology increases the surface area and reduces the interfacial area between film and substrate. Consequently, the surface activity is markedly enhanced while deleterious interfacial effects between film and substrate are significantly reduced. Both effects are highly advantageous for gas sensing applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.134-135
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• 2007

Growth of cubic SiC has been carried out on oxided Si substrate using atmospheric pressure chemical vapor deposition (APCVD). Hexamethyldisilane (HMDS) was used as the single precursor and nonflammable mixture of Ar and $H_2$ was used as carrier gas. Epitaxial growth had performed depositions under the various $H_2$ conditions which were adjusted from 0 to 100 seem. The effects of $H_2$ was characterized by surface roughness, thickness uniformity, films quality and elastic modulus. Thickness uniformity and films quality were performed by SEM. Surface roughness and elastic modulus were investigated by AFM and Nano-indentor, respectively. According to the $H_2$ flow rate, Poly 3C-SiC thin film quality was improved not only physical but also mechanical properties.

• Korean Journal of Child Studies
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• v.30 no.6
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• pp.125-137
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• 2009

This study reviews facts and trends of harmful environments in the last decade that negatively affected children's development. Younger children have been exposed to harmful media, drugs, facilities, and objects. A matter of chemical substances contaminating in-door air has become quite controversial, recently. In order to provide a better understanding of harmful environments against children, there are great needs for a survey covering all ages based on the clear definition of the term harmful environments, research identifying its causal effects on child development in the context of both parent-child and peer relationships, and a longitudinal study processing its effects in a life-span perspective. It is suggested that by providing parent education and a plenty of cultural facilities as social efforts to create sound family culture, psycho-social and physical environments of children are improved. Furthermore, legal regulations and supervision on harmful environments are needed to be strengthened.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2003.11a
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• pp.63-67
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• 2003

Mercury, one of the most diffused and hazardous organ-specific environmental contaminants, exists in a wide variety of physical and chemical states. Although the reports indicate that the mercury induces a deleterious damage, little has been known from the investigations of its effects in living organisms. The purpose of this study is to evaluate the effects of mercury chloride and ionizing radiation. Prepubertal male F344 rats were administered mercury chloride in drinking water throughout the experimental period. Two weeks after whole body irradiation, organs were collected to analyze the induced injury. Serum levels of GOT, GPT, ALP, and LDH were checked in the experimental groups and the hematological analysis was accomplished in plasma. In conclusion, the target organ of mercury chloride seems to be urinary organs and the pattern of damage induced by mercury differs from that by irradiation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1581-1588
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• 2011

In this study, flow characteristics in a multi-cavity injection molding process were investigated. One of main problems occurred in the multi-cavity molding is a flow imbalance among cavities since it affects physical properties and quality of products. Charge imbalance is caused by the uneven shear stress. Therefore, changes in viscosity affect the physical properties of resin and injection conditions differ in the filling imbalance phenomenon. Through, this study focus on experimental studies of flow imbalance for PC and PP resin occurring in a balanced delivery system. Experimental results were compared with CAE results. By experimental and CAE analysis, main cause for the flow imbalance is temperature distribution in cross section of runner. New runner system with a simple change of runner shape was suggested to avoid the flow imbalance. A series of simulation to confirm feasibility of Volume Runner's effects was conducted using injection molding CAE.

• International Journal of Control, Automation, and Systems
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• v.2 no.2
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• pp.228-237
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• 2004

This paper provides a motion analysis of soft-fingertip object manipulation tasks by presenting a dynamic model of multi-fingered object manipulations with soft fingertips. It is fundamentally observed that soft fingertips employed in a multi-fingered hand generate some deformation effects during the manipulation process and also that those effects are closely related to the behavior of the manipulated object. In order to analyze the motion of using soft fingertips, a dynamic manipulation control scheme is presented. Simulation and experimental results demonstrate the motion of soft-fingertips applied in object manipulating tasks and are further used to discuss the characteristics of soft-fingertip motions.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.598-606
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• 2001

A mathematical model is proposed that can depict the kinetics of simultaneous saccharification and fermentation (SSF) using steam-exploded wood(SEW) with a glucose- and cellobiose-fermenting yeast strain. Brettanomyces custersii. An expression to describe the reduction of the relative digestibility during the hydrolysis of the SEW is introduced in the hydrolysis model. The fermentation model also takes two new factors into account, that is, the effects of the inhibitory compounds present in the SEW hydrolysates on the microorganism and the fermenting ability of Brettanomyces custersii, which can use both glucose and cellobiose as carbon sources. The model equations were used to simulate the hydrolysis of the SEW, the fermentation of the SEW hydrolysates, and a batch SSF, and the results were compared with the experimental data. The model was found to be capable of representing ethanol production over a range of substrate concentrations. Accordingly, the limiting factors in ethanol production by SSF under the high concentration of the SEW were identified as the effect of inhibitory compounds present in the SEW, the enzyme deactivation, and a limitation in the digestibility based on the physical condition of the substrate.

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.817-828
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• 2023

Deteriorating soil physical properties and increasing soil pathogens due to the continuous cultivation of field crops are the leading causes of productivity deterioration. Crop rotation, soil heat treatment, and chemical control are used as pest control methods; however, each has limitations in wide application to domestic agriculture. In particular, chemical control requires improvement due to direct exposure to sterilizing solution, odor, and high-intensity work. To improve the overall domestic agricultural environment, the problems of time and cost, such as field maintenance and cultivation scale, must be addressed; therefore, mechanization technology for chemical control must be secured to derive improvement effects in a short period. Most related studies are focused on the control effect of the DMDS (dimethyl disulfide) sterilizer, and research on the performance of the sterilization spray device has been conducted after its introduction in Korea, but research on the corrosion suitability of the material is lacking. This study conducted a corrosion test to secure the corrosion resistance of a soil sterilizer injection pump, and a mechanical failure mode by corrosion by the material was established. The corrosion test comprised operation and neglect tests in which the sterilizing solution was circulated in the pump and remained in the pump, respectively. As a result of the corrosion test, damage occurred due to the weakening of the mechanical strength of the graphite material, and corrosion resistance to aluminum, stainless steel, fluororubber, and PPS (polyphenylene sulfide) materials was confirmed.