• KIEAE Journal
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• v.14 no.3
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• pp.105-109
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• 2014

The recent rising living standards, environment-friendly, well-being and health aspects of life in the basic gratification, as well as the desire for a pleasant environment emotionally environmentally friendly way of external space or industrial interest in the indoor environment, the manifestation. In particular, the biggest problem of the indoor environment has been emerged as a Sick House Syndrome indoor space that is provided to the building materials, and the impact on the domestic and the indoor environment, and clean the house in a health standards are specified as laws. The performance rating and the various materials to create environmentally-friendly standards for building materials. The more detail, Porous clay material, toxic substances released by applying the high humidity and the water itself, and to absorb the moisture, if the emissions, without a separate device, to maintain a comfortable indoor environment and at the same time, one of the causes of Sick House Syndrome breaking down harmful substances to absorb a comfortable indoor environment to maintain an environmentally-friendly building interior material studies. It is aimed at the development to multi-functional high performance eco-friendly construction materials, rather than through one feature performance, identify key features for national and international eco-friendly building materials can exert Water Vapour Adsorption raw, decomposed materials for the application and selection.

• Journal of Ginseng Research
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• v.39 no.2
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• pp.141-147
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• 2015

Background: Adipocytes, which are the main cellular component of adipose tissue, are the building blocks of obesity. The nuclear hormone receptor $PPAR{\gamma}$ is a major regulator of adipocyte differentiation and development. Obesity, which is one of the most dangerous yet silent diseases of all time, is fast becoming a critical area of research focus. Methods: In this study, we initially aimed to investigate whether the ginsenoside Rf, a compound that is only present in Panax ginseng Meyer, interacts with $PPAR{\gamma}$ by molecular docking simulations. After we performed the docking simulation the result has been analyzed with several different software programs, including Discovery Studio, Pymol, Chimera, Ligplus, and Pose View. All of the programs identified the same mechanism of interaction between $PPAR{\gamma}$ and Rf, at the same active site. To determine the drug-like and biological activities of Rf, we calculate its absorption, distribution, metabolism, excretion, and toxic (ADMET) and prediction of activity spectra for substances (PASS) properties. Considering the results obtained from the computational investigations, the focus was on the in vitro experiments. Results: Because the docking simulations predicted the formation of structural bonds between Rf and $PPAR{\gamma}$, we also investigated whether any evidence for these bonds could be observed at the cellular level. These experiments revealed that Rf treatment of 3T3-L1 adipocytes downregulated the expression levels of $PPAR{\gamma}$ and perilipin, and also decreased the amount of lipid accumulated at different doses. Conclusion: The ginsenoside Rf appears to be promising compound that could prove useful in antiobesity treatments.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6A
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• pp.425-433
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• 2011

In this study, in order to investigate the wave-induced buoyancy effects, experimental studies were conducted on pontoon-type floating structures. A series of small-scale tests with various wave cases were performed on the pontoon models. A total of four small-scale pontoon models with different lateral shapes and bottom details were fabricated and tested under the five different wave cases. Six hydraulic pressure gauges were attached to the bottom surfaces of the pontoon models and the wave-induced hydraulic pressure was measured during the tests. Finally, hydraulic pressures subjected to the bottoms of the pontoon models were compared with each other. As the results of this study, it was found that whereas the waffled bottom shape hardly influenced the wave-induced hydraulic pressure, the hybrid lateral shape significantly influenced the wave-induced hydraulic pressure subjected on the bottoms of floating structures. The air gap effects of the hybrid shape contribute to decreasing the wave-induced hydraulic pressure due to absorption of wave impact energy. Compared with box type, the hydraulic pressures of the hybrid type were about 83% at the bow, 74% at the middle, and 53% at the stern.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.2
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• pp.137-148
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• 2014

In this paper, design of a UWB MIMO antenna for an on-body application is proposed and antenna performance with body effect and the impact on the human body are investigated. The proposed MIMO antenna is composed of UWB antenna above ground plane and an additional plunger shaped isolator located between the two monopole antennas to enhance the isolation characteristic. The simulation and measurement are performed to analyze the effect of the human body on antenna performance when the human body is located in the near field of the antenna. According to the measurement results, the measured SAR values for antennas 1 and 2 are 0.132 W/kg and 0.08 W/kg, respectively when 0.5 mW input power is delivered. These values satisfy the FCC guideline which ragulates that the 1-g average SAR should be lower than 1.6 W/kg.

• Journal of Pharmaceutical Investigation
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• v.34 no.6
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• pp.443-452
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• 2004

Habit is the description of the outer appearance of a crystal. If the environment of a growing crystal affects its external shape without changing its internal structure, a different habit results. Crystal habit and the internal structure of a drug can affect bulk and physicochemical properties, which range from flowability to chemical stability. A polymorph is a solid crystalline phase of a given compound resulting from the possibility of at least two different arrangements of the molecules of that compound in the solid state. Chemical stability and solubility changes due to polymorphism can have an impact on a drug's bioavailability and its development program. During crystallization from a solution, crystals separating may consist of a pure component or be a molecular compound. Solvates are molecular complexes that have incorporated the crystallizing solvent molecule in their lattice. When the solvent incorporated in the solvate is water, it is called a hydrate. To distinguish solvates from polymorphs, which are not molecular compounds, the term pseudopolymorph is used. Identification of possible hydrate compounds is important since their aqueous solubilities can be significantly less than their anhydrous forms. Conversion of an anhydrous compound to a hydrate within the dosage form may reduce the dissolution rate and extent of drug absorption. An amorphous solid may be treated as a supercooled liquid in which the arrangement of molecules is random. Amorphous solids lack the three-dimensional long-range order found in crystalline solids. Since amorphous forms are usually of higher thermodynamic energy than corresponding crystalline forms, solubilities as well as dissolution rates are generally greater. A study on crystal form includes characterization of (l)crystal habit, (2)polymorphism, (3)pseudopolymorphism, (4)amorphous solid.

• Proceedings of the Korean Society of Crop Science Conference
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• 1998.10a
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• pp.313-335
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• 1998

If the atmospheric concentrations of greenhouse gases double, the annual temperature increase in mean surface temperature relative to 1990 will be about 2.0 to $2.5^{\circ}C$ and the annual precipitation increase about $15{\%}$ by 2100 in Korea. When the temperature rises $2^{\circ}C$, the annual temperature will be $13^{\circ}C,\;15^{\circ}C,\;and\;16^{\circ}C$ in Western Central, Yeongnam Basin, and Southern Coastal respectively. Consequently the crop period could be prolonged $10{\~}29$ days. In the case of gradual global warming, annual crops could be adapted to the changed environment by breeding, and the perennial crops should be shifted to ether area. If global warming happens suddenly over the threshold of atmospheric greenhouse gases concentration, then we shall have disturbance of ecosystem. When $2^{\circ}C$ higher than present, the optimum flowering date of rice plant delayed about 10 days, so it may not possible to adopt the fate with present japonica rices, therefore, the recommended characteristics of rice varieties are longer basic vegetative period, more late maturing and higher ripening temperature. Barley and wheat crops could be shifted to northern coastal areas and apple production areas should be shifted to those areas under $13.5^{\circ}C$ in annual mean temperature at global warming. Ideotypes of crops under climate changes should have such ecological characteristics that are indispensable to accomplish the sustainable agriculture under increased $CO_{2}$ and temperature condition as the diversification of genetic resources from yield-oriented to biomass-oriented characteristics with the higher potentials of $CO_{2}$ absorption and Primary production. In addition, a heat-tolerance, a pest resistance, an environmental adaptability and a production stability should be also incorporated collectively into our integrated agroecosystem.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.2
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• pp.193-200
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• 2009

This paper investigated the drop characteristics of oleo pneumatic type landing gear for small aircraft and the effects of cavitations in modeling the landing gear system. The landing gear system employed a simple oleo pneumatic type damper without a metering pin. In general, oleo-pneumatic type landing gears are light-weighted because of it's simplicity, yet they offer excellent impact absorption characteristics. In this study, the landing gear system was modeled using MSC ADAMS, which offers a drop simulation module. After modeling the system, a series of testing was conducted, using a prototype landing gear system, to validate the analysis model and simulation results. The effect of cavitation was considered in the simulation model to obtain a better correlation between the test and simulation results. The results show that adding the cavitation effect in the simulation model significantly improved the simulation model and better captured the dynamic behaviors of the landing system. Using the 'cavitation' model, dynamics characteristics of the landing gear were further evaluated for other landing conditions, such as landing in various angles of slopes.

• Journal of the Korean Institute of Gas
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• v.17 no.5
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• pp.37-41
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• 2013

This paper presents the strength safety of stress and deformation behaviors using the finite element method as a function of the thickness of the protective helmets with and without an extruder on the top of the shell structure. The helmet that would provide head and neck protections without causing discomfort to the user when it was worn for long periods of time should be manufactured for increasing the safety and impact energy absorption. The stress analyzed results show that when the impulsive force of 4,540N is applied on the top surface of a helmet, the safe thickness is 3.7mm for the conventional helmet and 3.2mm for the modified new helmet. Based on the deformation analysis, the FEM results recommend that the safe thickness is 3.2mm for the conventional helmet and 2.0mm for the modified new helmet. Thus, it may be more safe design of the helmet, which has an extruded structure on the summit surface of the helmet.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.9
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• pp.991-997
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• 2011

This paper deals with the basic principles and procedures involved in the steam-chest molding process used for manufacturing expanded polypropylene (EPP) bead foam. Steam-chest molding is an integral process for EPP technology. However, little research has been carried out on the processing conditions for steam-chest molding this process. The characteristics of EPP foam are energy absorption, multiple-impact protection, low weight, structural strength, and durability. In this study, the steam pressure in steam-chest molding was varied to determine the optimum conditions for manufacturing EPP foam. Moreover, annealing was performed after EPP-foam molding to prevent the shrinkage of the steam-molded product. It was possible to verify the mechanism of foam shrinkage by observing the change in weight with time at different annealing temperatures. Moreover, a tensile test and scanning electron microscopy (SEM) analysis were performed to support these experimental results. The dimensional stability of each molded product was investigated at different steam pressures.

• Journal of Preventive Medicine and Public Health
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• v.22 no.4 s.28
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• pp.518-527
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• 1989

The relationship between copper content in scalp hair and mental retardation was investigated. Samples of scalp hair were collected from 297 mentally retarded children who were students in one of two schools providing special educational services, one, consisted of children living in an orphan home, the other, children living with parents. For comparison, 117 scalp hair samples were collected from the children who had got average or above average academic achivement in a regular elementary school. Hair samples were taken from the nape of the neck and the copper content was determined by an atomic absorption spectrophotometer (IL 551). There was no statistically significant difference in scalp copper levels across different age groups except female orphan group, but no trend or correlation between copper conents and age was found. The hair copper contents of the mentally retarded children groups were significantly lower than that of control groups. But there was no dose-response relationship between degree of mental retardation and hair copper level. The hair copper contents of the group accompanied by Down's syndrome and unknown group were significantly lower than that of control group in both sex, and in the case of accompanied by epilepsy or autism, lower than control group in male. Although the results of this study show no evidence that mental retardation has owed to copper deficiency, the possibility of copper deficiciency in their fetal or infant age could not be ruled out. Thus further study is needed to determine whether mental retardation could be attributed to copper deficiency, through the examinations about their living environments, dietary pattern, eating habit and the impact of copper deficiency on brain development.