• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.3
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• pp.153-164
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• 2007

Nowaday, in Korea, many u-City projects have been developed as a core business in the new town development project by national or local level of government. However, the new business projects have some problems, such as excessive number of u-services, increased project funds and period, and lower u-services due to lack of u-service evaluation methodologies. Therefore, this paper proposes a new u-service evaluation methodology to solve current problems. The methodology gives an ability to guard general u-service groups for reaching the main goal of the u-City project, and then select alternative u-service groups against being limited by the law and technology in the project year. Besides, as a key variable on performing u-City plans, the complexity between stakeholders is considered in the methodology. Finally, through the Optimal Sequential Method in the methodology, the maximum value of u-service group is obtained as a optimal service group of u-City.

• Applied Microscopy
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• v.34 no.1
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• pp.51-59
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• 2004

The high acceleration voltage system used in scanning electron microscope were designed and manufactured to test its stability. The Cockcroft-Walton circuits are used both in the cathode voltage up to -30 kV and in the Wehnelt cylinder of -2 kV. The operating voltage of 6 V was applied to the heating of the filament. The wave forms which are formed in the second leg of the high voltage transformer were observed in the oscilloscope with 2 V of DC input. When the high voltages were in the range between 5 kV and 12 kV, the highest value of the stabilities of the generated voltages was obtained as 0.002%.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.4
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• pp.665-672
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• 2001

Fibrillation is caused by wet abrasion and occurs during scouring treatments, domestic laundering and wet finishing. So, for clean fabrics, fibrillation must either be prevented or removed after it has occurred. In this study, we researched the influence thickness of tencel on fibrillation occurrence. And the three methods of SEM photograph, reflectance values and gray level values were used in order to present proper evaluation method for fibrillation. The results are as follows. The thickness of tencel was high affected with occurrence of fibrillation, that is, as the thickness of fabrics thicker, the fibrillation occurer. And all method applicated as fibrillation evaluation method very effected without big difference, but they come into be a little question in the side of exactness.

• Structural Engineering and Mechanics
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• v.31 no.5
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• pp.527-544
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• 2009

In this study, the periodic seismic performance evaluation scheme is proposed using a structural health monitoring system in terms of seismic fragility. An instrumented highway bridge is used to demonstrate the evaluation procedure involving (1) measuring ambient vibration of a bridge under general vehicle loadings, (2) identifying modal parameters from the measured acceleration data by applying output-only modal identification method, (3) updating a preliminary finite element model (obtained from structural design drawings) with the identified modal parameters using real-coded genetic algorithm, (4) analyzing nonlinear response time histories of the structure under earthquake excitations, and finally (5) developing fragility curves represented by a log-normal distribution function using maximum likelihood estimation. It is found that the seismic fragility of a highway bridge can be updated using extracted modal parameters and can also be monitored further by utilizing the instrumented structural health monitoring system.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.1
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• pp.187-199
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• 2009

Objectives : The electroacupuncture was generally has been used in oriental medicine doctors. In recent years, there have been a few studies about safety and stability of acupuncture needle in itself, but then again research of acupuncture needle safety and stability on applying electroacupuncture have been insignificant. Therefore we investigated the safety and change in mechanical characteristic of acupuncture needle in electroacupuncture therapy. Methods : We observed mechanical characteristic change by SEM(Scanning Electron Microscope) and EDX(Energy Dispersive X-ray Spectroscopy), evaluated the hardness by vickers hardness tester. We used MTT assay and cell stain to study about biocompatibility of electroacupuncture. Results : In this study, any corrosion of material, alternation of elements, and change of hardness were not observed in surface analysis using SEM and EDX. In cytotoxity evaluation using MTT assay and cell stain, cell survival rate was low when practicing the electroacupuncture for more than 3 hours. Conclusions : Change of mechanical property was not observed based on the test results using surface analysis and hardness estimation by the electroacupuncture. And considering the biocompatibility, electroacupuncture was thought to be safe in an hour based on cytotoxity evaluation using MTT assay and cell stain.

• Textile Coloration and Finishing
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• v.17 no.5 s.84
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• pp.26-36
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• 2005

This study was carried to evaluate mechanical characteristics of Poly(ethylene terephthalate) fabrics (by Kawabata evaluation system(KES)) which was systematically treated with $O_2$ low temperature plasma and chitosan acetate solution. Furthermore, surface structure was investigated by SEM, AFM, air permeability and wettability. Tensile energy(WT), shear rigidity(G) and surface roughness(MIU) properties calculated by KES-FB have increased with increasing plasma treatment time, while bending rigidity(G) and energy of compression(WC) value were decreased compared with those of the untreated. SEM photographs showed the identification of chitosan coating but did not confirm the plasma etching structure. Air permeability was decreased according to plasma treatment time with increasing concentrations of chitosan. The water absorption rate made rapid progress by chitosan treatment.

• Korean journal of food and cookery science
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• v.6 no.3 s.12
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• pp.33-41
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• 1990

This study was conducted to compare the characteristics of the ordinary soybean curd and 3 protein-adding soybean curds (soy protein, casein, gelatin). The sensory evaluation, textural analysis by Instron Universal Testing Machine & the microstructure analysis by SEM for 4 soybean curds were carried out. The results were as follows: 1. In sensory evaluation. 1) The differentiation of soybean curds was greatly explained by `hardness in mouth' through ANOVA test. 2) Discriminant analysis showed that the properties of casein soybean curd were different from those of other three soybean curds by discriminant function I, and the properties of soy protein soybean curd were slightly different from those of ordinary and gelatin soybean curds by discriminant function II. 2. In textural analysis by Instron, protein-adding soybean curds showed significantly lower hardness than ordinary soybean curd. 3. In microstructure analysis by SEM, soy protein soybean curd showed regular, good honeycomb-like network structure and other soybean curds showed lumpy network. The structure of gelatin soybean curd was slightly similar to that of ordinary soybean curd.

• Korean journal of food and cookery science
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• v.17 no.5
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• pp.431-440
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• 2001

This study was carried out to investigate the effects of oligosaccharide addition on Jeung-Pyun fermentation. Fructooligosaccharide (FOS), isomaltooligosaccharide (IMOS), galactooligosaccharide (GOS) were used at the concentration of 15%, 25% or 35% of the rice in Jeung-Pyun ingredients. The physicochemical properties, sensory evaluation and instrumental characteristics were examined. The internal structure of Jeung-Pyun samples was observed by SEM. The pH of Jeung-Pyun batters was decreased as the fermentation progressed. Compared with the control using sucrose, the specific volume of Jeung-Pyun was higher in the 15% and 25% of oligosaccharide-added samples. The degree of gelatinization decreased more slowly than control as the storage time increased both at 20$\^{C}$ and 4$\^{C}$. In sensory evaluation, Jeung-Pyun with FOS and IMOS at the levels of 25∼35% and GOS at the levels of 25% showed the best scores. In instrumental characteristics, springiness, gumminess, hardness and cohesiveness were similar among all samples during storage at 20$\^{C}$ and 4$\^{C}$. In the internal structure of Jeung-Pyun observed by SEM, Jeung-Pyun substituted with oligosaccharide at the levels of 25% for sucrose showed large and regularly distributed air pores. In conclusion, the replacement of sucrose with oligosaccharide in Jeung-Pyun ingredients appeared acceptable in terms of fermentative aspects.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.861-868
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• 2021

To confirm the influence of modified starch on frozen storage stability, the microstructure and sensory characteristics of fish cakes, called Eomuk in Korea, by using seven varieties of starch, including native starch (NS), physically treated corn starch (MS) and modified starch [treatment with acetate (SA-1, SA-2 and SA-3), hydroxypropyl (HS), and acetylated distarch adipate (ADA)] were evaluated. Scanning electron microscopy (SEM) photographs showed fish cakes with NS had a finer and denser network structure than those made with modified starches. During frozen storage, fish cakes with HS and ADA exhibited a stable structure, as evaluated by porosity and rough surface. The results of the sensory evaluation showed that modified starch, including HS, SA-2 and ADA, increased the taste and firmness of the fish cakes, while NS, MS and the modified starch SA-3 resulted a decrease in the sensory properties during storage. Therefore, HS, SA-2 and ADA are suitable additives to improve the sensory quality of frozen fish cakes.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.6
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• pp.63-71
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• 2015

The objective of the present study is to investigate how elevated temperature ranging from $100^{\circ}C$ to $800^{\circ}C$ as well as room temperature affects the variation of mechanical properties of high strength concrete ($over\;f_{ck}=60MPa\;grade$). In this experiment, specimens were exposed for a period of $2^{\circ}C/min$ to temperatures of $20^{\circ}C$, $100^{\circ}C$, $200^{\circ}C$, $300^{\circ}C$ $400^{\circ}C$, $500^{\circ}C$, $600^{\circ}C$, $700^{\circ}C$ and $800^{\circ}C$, respectively. Accordingly, the study investigated the fire resistance performance of high strength concrete mixed with composite fibers which composed with hybrid fibers and steel fibers. After cooling down to ambient temperature, the following basic mechanical properties were then evaluated and compared with reference values obtained prior to thermal exposure: (i) compressive strength in room temperature; (ii) residual compressive strength; (iii) Poisson's ratio; (iv) weight change; (v) SEM analysis & XRD analysis In addition, XRD and SEM Images analyses were performed to investigate chemical and physical characteristics of high strength concrete with composite fibers according to high temperature.