• Archives of design research
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• v.21
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• pp.99-106
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• 1997

There were the changes of shapes and color tones when the soil materials e.g. Blue-Porcelain, White-Porcelain, Bunchong, mixed A and B, mullite, Sanchong and Ongki - used by most domestic ceramic artists - were glazed at $ 950^{\circ}C,; 1200^{\circ}C,; 1250^{\circ}C,; 1280^{\circ}C,;1300^{\circ}C$ After the materials were dried out at 120t: in an electric oven, they were mixed with water, keeping the percentage of moisture content 25% and kneaded specimens which are hexahedron by $$ 250{\times}30{\times}8mm$$were produced and dried after calibrated at 200mm interval with a vernier caliper. After the materials were dried and glazed, they showed few shape-changes at $950^{\circ}C$ but began to changed at $1200^{\circ}C$,especially Bunchong and Ongki made rapid changes. In the case of color-change, White-Porcelain changed very little. The color of Blue-Porcelain, mixed A and B, Sanchong, Mullite changed to ]aune brilliant as temperature went up but Bunchong and Ongki changed to dark brown or dark chocolate under the same conditions. This study aims at suggestion of the basic data which minimize failure rates by recognizing the property of the materials on the basis of this study and regulating shape-change phenomena and sensitive changes of color when ceramic artists work.

• Journal of Environmental Impact Assessment
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• v.20 no.4
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• pp.497-507
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• 2011

This research studied human health risk assessment of benzene from industrial complexes of Chungcheong Province (Seosan industrial complex) and Jeonla Province (Iksan industrial complex and Yeosoo industrial complex). The residents near the industrial complexes areas can be often exposed to volatile organic compounds (e.g., benzene, toluene, xylenes) through a number of exposure pathways, including inhalation of the organic pollutant via various environmental matrices (air, water and soil), contaminated water, and soil intake. Benzene is well known to be a common carcinogenic and toxic compound that is produced from industrial and oil refinery complexes. In this study, a number of samples from water, air, and soil were taken from the residential settings and public school zones located near the industrial complex sites. Based on the carcinogenic risk assessment, the risk estimates were slightly above $10{\times}10^{-6}$ at all three industrial sites. According to deterministic risk assessment, inhalation was the most important route. The distribution of benzene in the environment would be dependent on vapor pressure, and the physical property influencing the extent of the potential risks. Non-carcinogenic risk assessment of benzene shows that the values of Hazard Index(HI) were much lower than 1.0 at all industrial complexes. Therefore, benzene was not a cause of concern in terms of non-carcinogenic risk posed to the residents near the sites. When compared to probabilistic risk assessment, the CTE(central tendency exposure) cancer risk values of deterministic risk assessment were close to the mean values predicted by the probabilistic risk assessment. The RME(reasonable maximum exposure) values fell within the range of 95% to 99.9% estimated by the probabilistic risk assessment. Since the values of carcinogenic risk assessment were higher than $10{\times}10^{-6}$, further detailed monitoring and refined risk assessment for benzene may be warranted to estimate more reliable and potential inhalation risks to receptors near the industrial complexes.

• Applied Biological Chemistry
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• v.28 no.2
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• pp.51-55
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• 1985

Dried black soybeans were soaked in water at the temperature range of $4^{\circ}C{\sim}100^{\circ}C$ and in salt or sugar solution at $100^{\circ}C$ in order to investigate their effects on the cooking ratio and diffusion property of color pigments. As the temperature increased, the equilibrated absorbance at 490nm of soaking water after 120min was linearly increased. The activation energy for diffusion of color pigments were found to be 4.23 Kcal/mole at the range of $60^{\circ}C{\sim}100^{\circ}C$ and 8.31 kca1/mo1e at $4^{\circ}C{\sim}60^{\circ}C$. The cooking ratio, % cooked beans after heating, of black soybeans were more affected by the salt concentration that of sugar. Both concentrations reduced the cooking ratio as they increased. The sorption isotherm of Kongjaban showed a quite different curves between the storage at $4^{\circ}C$ and $25^{\circ}C$. The sorption and desorption rates during storage could be represented by the equation of $log({\frac{dw}{dt}}{\times}10^3))=alogt+logb$ with a very high correlation.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1131-1143
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• 2018

This study aimed to investigate the drying yield, meat quality, oxidation stability and sensory properties of Hanwoo beef loin subjected to different dry-aging conditions. A total of 54 Hanwoo beef loins (bone-in, $6^{th}-13^{th}$ ribs) with fat cover at 2 d postmortem were assigned to four groups and hung in a dry-aging room at a controlled temperature ($2^{\circ}C-4^{\circ}C$), humidity (65%-85%) and air velocity (3 m/s). Four treatment conditions were tested; the respective temperature, humidity and treatment duration are as follows: T1, $2^{\circ}C$, 85%, 60 d; T2, $2^{\circ}C$, 65%, $20d+2^{\circ}C$, 75%, $20d+4^{\circ}C$, 85%, 20 d; T3, $2^{\circ}C$, 75%, $20d+4^{\circ}C$, 85%, 40 d; T4, $4^{\circ}C$, 85%, 60 d. The drying yield, total aerobic counts and fat contents increased, whereas the moisture content, meat color (CIE $L^*$, $a^*$, and $b^*$), and Warner-Bratzler shear force values decreased significantly during the aging period for all treatments (p<0.05). The cooking loss (%) did not change significantly until 40 d, and it was significantly higher in T1 and T4 than in T2 and T3 at 60 d (p<0.05). The water-holding capacity, pH and lipid oxidation [thiobarbituric acid reactive substance (TBARS) values] increased during aging (p<0.05). The sensory scores for tenderness, juiciness, flavor, and overall acceptability of dry-aged loin muscles increased as the aging period increased. T2 and T3 had significantly higher sensory scores and T1 had significantly lower scores for tenderness, juiciness, flavor, and overall acceptability at 20, 40, and 60 d for loin muscles (p<0.05).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.13-19
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• 2021

This study examined the effects of stacking faults on the thermoelectric properties for n-type SiC semiconductors. Porous SiC semiconductors with 30~42 % porosity were fabricated by the heat treatment of pressed ��-SiC powder compacts at 1600~2100 ℃ for 20~120 min in an N2 atmosphere. XRD was performed to examine the stacking faults, lattice strain, and precise lattice parameters of the specimens. The porosity and surface area were analyzed, and SEM, TEM, and HRTEM were carried out to examine the microstructure. The electrical conductivity and the Seebeck coefficient were measured at 550~900 ℃ in an Ar atmosphere. The electrical conductivity increased with increasing heat treatment temperature and time, which might be due to an increase in carrier concentration and improvement in grain-to-grain connectivity. The Seebeck coefficients were negative due to nitrogen behaving as a donor, and their absolute values also increased with increasing heat treatment temperature and time. This might be due to a decrease in stacking fault density, i.e., a decrease in stacking fault density accompanied by grain growth and crystallite growth must have increased the phonon mean free path, enhancing the phonon-drag effect, leading to a larger Seebeck coefficient.

• Structural Engineering and Mechanics
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• v.90 no.6
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• pp.551-568
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• 2024

The present study deals with static and dynamic behaviors including forced vibrations of an elastic rectangular nano plate on the two-parameter foundation. Firstly, the rectangular plate is assumed to be subjected to uniformly distributed and eccentrically applied concentrated loads. The governing equations of the problem are derived by considering the dynamic response of the plate, employing a series of the Chebyshev polynomials for the displacement function and applying the Galerkin method. Then, effects of the non-essential boundary conditions of the plate, i.e., the boundary conditions related to the shearing forces, the bending moments and the corner forces, are included in the governing equation of motion to compensate for the non-satisfied boundary conditions and increase the accuracy of the Galerkin method. The approximate numerical solution is accomplished using an iterative process due to the non-linearity of the unilateral property of the two-parameter foundation. The plate under static concentrated load is investigated in detail numerically by considering a wide range of parameters of the plate and the foundation stiffnesses. Numerical treatment of the problem in the time domain is carried out by assuming a stepwise variation of the concentrated load and the linear acceleration procedure is employed in the solution of the system of governing differential equations derived from the equation of motion. Time variations of the contact region and those of the displacements of the plate are presented in the figures for various numbers of the two-parameter of the foundation, as well as the classical and nano parameters of the plate particularly focusing on the non-linearity of the problem due to the plate lift-off from the unilateral foundation. The effects of classical and nonlocal parameters and loading are investigated in detail. Definition of the separation between the plate and the two-parameter foundation is presented and applied to the given problem. The effect of the lift-off on the static and dynamic behavior of the rectangular plate is studied in detail by considering various loading conditions. The numerical study shows that the effect of nonlocal parameters on the behavior of the plate becomes significant, when nonlinearity becomes more profound, due to the lift-off of the plate. It is seen that the size effects are significant in static and dynamic analysis of nano-scaled rectangular plates and need to be included in the mechanical analyses. Furthermore, the corner displacement of the plate is affected more significantly from the lift-off, whereas it is less marked in the time variation of the middle displacement of the plate. Several numerical examples are presented to examine the sensibility of various parameters associated with nonlocal parameters of the plate and foundation. Both stiffening and softening nonlocal parameters behavior of the plate are identified in the numerical solutions which show that increasing the foundation stiffness decreases the extent of the contact region, whereas the stiffness of the shear layer increases the contact region and reduces the foundation settlement considerably.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.12 s.138
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• pp.1596-1604
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• 2004

Quality Function Deployment(QFD) is a product development tool which ensures that the voice of the customer needs is heard and translated into products. To develop a sensible brassiere for middle-aged women QFD was adopted. In this study the applicability and usefulness of QFD was examined through the engineering design process for a sensible brassiere for middle-aged women. The customer needs for the wear comfort of brassiere was made by one-on-one survey of 100 women who aged 30-40. The customer competitive assessment was generated by wearing tests of 10 commercial brassieres. The subjective assessment was conducted in the enviornmental chamber that was controlled at $28{\pm}1^{\circ}C,\;65{\pm}3\%RH.$ As a results, we developed twenty-one customer needs and corresponding HOWs for the wear comfort of brassiere. The Customer Competitive Assessment was generated by wearing tests of commercial brassiere. The subjective measurement scale and dimension for the evaluation of sensible brassiere were extracted from factor analysis. Four factors were fitting, aesthetic property, pressure sensation, displacement of brassiere due to movement. The most critical design parameter was wire-related property and second one was stretchability of main material of brassiere. Also, wearing comfort of brassiere was affected by the interaction of initial stretchability of wing and support of strap. Engineering design process, QFD was applicable to the development of technical and aesthetic brassieres.

• Journal of the Korean Vacuum Society
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• v.17 no.6
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• pp.528-537
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• 2008

60 nm and 20 nm thick hydrogenated amorphous silicon(a-Si:H) layers were deposited on 200 nm $SiO_2$/single-Si substrates by inductively coupled plasma chemical vapor deposition(ICP-CVD). Subsequently, 30 nm-Ni layers were deposited by an e-beam evaporator. Finally, 30 nm-Ni/(60 nm and 20 nm) a-Si:H/200 nm-$SiO_2$/single-Si structures were prepared. The prepared samples were annealed by rapid thermal annealing(RTA) from $200^{\circ}C$ to $500^{\circ}C$ in $50^{\circ}C$ increments for 40 sec. A four-point tester, high resolution X-ray diffraction(HRXRD), field emission scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM), and scanning probe microscopy(SPM) were used to examine the sheet resistance, phase transformation, in-plane microstructure, cross-sectional microstructure, and surface roughness, respectively. The nickel silicide from the 60 nm a-Si:H substrate showed low sheet resistance from $400^{\circ}C$ which is compatible for low temperature processing. The nickel silicide from 20 nm a-Si:H substrate showed low resistance from $300^{\circ}C$. Through HRXRD analysis, the phase transformation occurred with silicidation temperature without a-Si:H layer thickness dependence. With the result of FE-SEM and TEM, the nickel silicides from 60 nm a-Si:H substrate showed the microstructure of 60 nm-thick silicide layers with the residual silicon regime, while the ones from 20 nm a-Si:H formed 20 nm-thick uniform silicide layers. In case of SPM, the RMS value of nickel silicide layers increased as the silicidation temperature increased. Especially, the nickel silicide from 20 nm a-Si:H substrate showed the lowest RMS value of 0.75 at $300^{\circ}C$.

• Archives of design research
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• v.17 no.2
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• pp.43-54
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• 2004

The appreciation of cultural properties related with what the aspects of society was is mandatory to understand our culture correctly. To make over all cultural properties to our descendants without breakage or damage is our natural duty and national obligation. On the contrary, inhabitants in the preserved area should be restricted and controlled by the cultural property law. The conflict between the inhabitants in the preserved area and the government raises economical problems and damages all the time. Especially it is time to discuss to mediate between them and solve the problems. This feasible study is a proposal to settle them up through renovating abolished school in the preserve area to the museum and a case to preserve the cultual properties as well as habitant's assets in that area.

• Journal of the Korea Institute of Building Construction
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• v.20 no.2
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• pp.137-145
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• 2020

The recent bridge construction projects demand thorough and systematic safety and risk management, due to the increase of risk factors following the introduction of new and complex construction methods and technologies. Among many types of damages that can occur in bridge construction projects, the damages to third parties who are not directly related to the existing property of the contractor construction project can also bring about critical loss in the project in order to compensate the damages. Therefore, risks that could be caused by the loss occurred to indemnify the third party damages should be clearly analyzed, although there are not subsequent amount of studies focusing on the issue. Based on the past record of insurance payment from domestic insurance companies for bridge construction projects, this study aimed to analyze the risk factors of bridge construction for loss caused to compensate the third-party damages happened in actual bridge construction projects and to develop a quantified and numerical predictive loss model. In order to develop the model, the loss ratio was selected as the dependent variable; and among many analyzed independent variables, the superstructure, foundation, flood, and ranking of contractors were the four significant risk factor variables that affect the loss ratio. The results produced can be used as an essential guidance for balanced risk assessment, supplementing the existing analysis on material losses in bridge construction projects by taking into account the third-party damage and losses.