• Journal of Wetlands Research
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• v.10 no.3
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• pp.27-35
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• 2008

Sediment cores were obtained from Upo and Mokpo in Upo Wetland and core samples were divided by depth into 20 ~ 21 subsamples. The heavy metal concentrations of Fe, Mn, Zn, AS, Cu, Cd, Ni, Pb, and Cr in the sediments of each depth were determined by ICP-MS. The texture of sediemnts from Upo Wetland appeared to be clayey silt with average grain size of $7.52{\sim}11.15{\mu}m$ for physical properties. It was found to have a clear tendency of depth profile with respect to TOC and ignition loss. Organics were stabilized in the range of 0.5 ~ 0.7 % TOC and 8 ~ 9 % ignition loss in 30 years, whereas, the surficial sediments have the highest concentrations of about 3.0 % of TOC and 13 ~ 15 % ignition loss. Those are much higher than the values of the main stream, the Nakdong River, which reflects the deposit of biodegradable organics from plants and other lifes. The vertical distribution of heavy metals in two sediment cores was investigated to elucidate historical trends of heavy metals deposited into Upo wetland. The depth profile concentrations of each heavy metal were compared and discussed with the Concensus-Based Sediment Quality Guidelines for freshwater ecosystems. All the Cd data for the vertical distribution in the sediments were detected above PEC value for Cd, which predict harmful effects on sediment-dwelling organisms expected to occur frequently. The concentrations of Zn, Cu, and Cr in all sediment samples for depth profile were detected below the TEC values, which provided a basis predicting the absence of toxicity by Zn, Cu, and Cr.

• Tribology and Lubricants
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• v.19 no.3
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• pp.123-132
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• 2003

The effect of surface texture on elastohydrodynamic lubrication (EHL) point contact of a ball Joint mechanism in small reciprocating compressors is studied numerically by using multigrid method. Pressure and film thickness profiles have been calculated for surface roughness with waviness of different orientations and transverse ridge and dent at minimum and maximum Hoes M parameter conditions. The influence of the amplitude and the wavelength of the surface roughness was also studied. Results show that the oblique waviness with orientation angle of 30$^{\circ}$generates the smallest minimum film thickness as compared with those of longitudinal, transverse, and other oblique roughness. The influence of transverse waviness on the minimum film thickness is smaller than for the longitudinal waviness case.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.255-262
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• 1999

This paper summarizes the results of a study which uses the recently developed Optical Profile Microscopy technique (Dove and Frost, 1996) as the basis for investigating the role of geomembrane surface roughness on the shear strength of goomembrane/geotextile interfaces. The results show that interface friction can be quantitatively related to the surface roughness of the geomembrane. The peak and residual interface strengths increase dramatically through the use of textured geomembranes as opposed to smooth geomembranes. For the smooth geomembranes, the sliding of the geotextile is the main shear mechanism. For the textured geomembranes, the peak interface strength is mainly mobilized through the micro-texture of the geomembrane, however, the residual interface strength is primarily attributed to macro scale surface roughness which pulls out and breaks the filaments from the geotextile. The results of this study can be extended to the other interfaces such as joints in rock mass, and also can be used to provide a quantitative framework that can lead to a significantly improved basis for the selection and design of geotextiles and geomembranes in direct contact.

• Journal of Korean Society for Quality Management
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• v.33 no.4
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• pp.103-110
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• 2005

Advanced function has been considered to be the most important aspect of the cellular phone. However, leading companies are now implementing the fashion branding strategy which stresses both high technology and appealing design. By means of the conjoint analysis, this research focuses on identifying the preferred design profile related to style of the key cover, color and texture of the case, and presence or absence of the noctilucent material coated on the part of surface. We also evaluate the relative importance of factors to determine the design concept of new cellular phone. Results indicate that consumers most prefer the silver-colored, sliding key cover phone with soft and noctilucent surface.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.119-124
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• 2002

Generally, Portland cement concrete(PCC) pavements have the advantage of durability and superior surface friction when compared to most dense-graded asphalt. However, It is known that PCC pavements create more noise than asphaltic surfaces due to the noise from interaction of tire and pavement surface. Recently exposed aggregate concrete(EAC) pavement was sugested to reduce traffic noise. So in this paper, we considered several materials and mixture proportions for proper depth of exposed aggregate which was measured by the sand patching test, and then according to those relationships, we tried to find out dosage of retarding agents and optimum mixture proportions for expecting good effects to noise reduction. It were also evaluated sound level at every conditions of surface texture as like depth of aggregate exposed, profile peak, distance of aggregate and types of aggregate.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.4
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• pp.64-75
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• 1991

The design of structures of modern industry has developed to satisfy stringent service, realiability and safety. Up to now, geometric profile which means surface foughness and dimension accuracy is mainly treated in manufacturing process of work surface. But it is inevitable to evaluate changes of surface geometry as well as the nature of alterations in surface layers because surface of workpiece changes as a result of phase transformation, chemical changes, plastic deformation and stress changes. This paper is to present principal data for safety design by verifying the effect of grinding conditions and method in grinding layers and to explain the method of measuring surface integrity. In this paper, structural steel(SM20C) is used as a workpiece. Of integrity, surface roughness in view of surface texture is analyzed by frequency domain and residual stress, structures and defect of ground layers in view of surface metallurgy are investigated.

• Transactions of Materials Processing
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• v.15 no.8 s.89
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• pp.574-580
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• 2006

Anisotropy has an important effect on the strain distribution in aluminum alloy sheet forming, and it is closely related to the thinning and formability of sheet metals. Thus, the anisotropy of the material should be properly considered for the realistic analyses of aluminum sheet forming processes. For this, anisotropy can be approached in two different scales: phenomenological and microstructural (polycrystal) models. Recent anisotropic models (Yld2000-2d; Barlat et al.[1] 2003, Cuitino et al.[2] 1992) were employed in this work. For the simulation using shell element, the method which can impose plane stress condition in the polycrystal model is developed. Lankford values and yield stress ratios are calculated along various directions. As planar anisotropic behavior, a circular cup deep drawing simulation was carried out to compare the phenomenological and microstructure models in terms of earing profile.

• Korean Journal of Human Ecology
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• v.7 no.1
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• pp.21-31
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• 2004

This study was carried out to investigate the physico-chemical properties during the rib-eye preperation while cooked rib-eye and fine sensory evaluation by various cooked utensil (oven, fry-pan and microwave). 1) Change of moisture contents of sauce-pan boiling cooker was lower than boiling by preasure cooker and fat content of sauce-pan boiling was higher than preasure cooker boiling. 2) Degree of cholesterol of cooker meat was not change for content of cholesterol during the boiling preperation but progressively decreased in order of well-done steak < medium steak < rare steak measured by cholesterol analysis. 3) Sensory evaluation conducted by fine graduate as panelists showed that oven steak and fry-pan steak had higher score of sensory evaluation. While microwave steak had the lowest score all sensory profile score.

• Journal of Dairy Science and Biotechnology
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• v.36 no.2
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• pp.73-80
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• 2018

The textural and rheological properties of cheese are major attributes for the characterization of cheese types, ripening, and consumer preferences. The use of small amplitude oscillatory rheological testing has made it possible for cheese researchers to assess the major properties of cheese, such as melting behavior and storage modulus, without irreversible deformation. In addition, large deformation testing such as textural profile analysis can assess properties such as hardness of cheese. While the sensory properties of cheese are valued by consumers, objective and reliable measurements are paramount for researchers. Ongoing development and refinement of scientific measurement methods of cheese are vital.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.5
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• pp.713-719
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• 2010

The objective of this study was to evaluate the quality characteristics of Dasik containing different levels of jujube paste (0%, 60%, 70%, 80%, 90%). Moisture composition of the paste ranged from 19~29% As the content of jujube paste increased, the lightness (L) and yellowness (b) decreased while redness (a) increased In the texture profile analysis, as the content of jujube paste in Dasik content increased, the hardness decreased Cohesiveness and springiness did not show significant differences according to amount of jujube paste. The results of the sensory evaluation show that sweetness, bitterness, and overall acceptability were the highest in Dasik containing 80% level jujube paste.