• KSBB Journal
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• v.27 no.3
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• pp.145-150
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• 2012

This study was accomplished using packed bed column reactors that contain nonsurface-modified polypropylene media and surface-modified media from hydrophobic surface property into hydrophilic property by ion beam irradiation. The objectives of this research was investigated the characteristics of organic compounds removal and microbe attachment from sewage of school cafeteria in these reactors. In 736.8 mg/L of the average inflow $COD_{Cr}$ concentration the reactors with and without surface modification showed 81.8% and 70.3% of average $COD_{Cr}$ removal efficiencies, respectively, which proves the $COD_{Cr}$ removal efficiency of surface-modified media reactor is higher than that of nonsurface-modified media reactor. After 90 days, there were maximum differences between modified system and non-modified system. In that time the maximum removal efficiency of $COD_{Cr}$ was 96.5% in modified system and was 85.2% in non-modified system that showed removal efficiency of surface-modified media system is 11.3% higher than that of nonsurface-modified media system. The average removal efficiency of SS was 80.4% for the surface modified system and 61.6% for the non-modified system under same condition. Also, the reactor of surface-modified media has advantage on microbe attachment and biofilm formation.

• Journal of Periodontal and Implant Science
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• v.30 no.1
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• pp.157-168
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• 2000

Periodontal surgery can be directed to remove the irritants from the tooth surface and reduce the periodontal pocket. The purpose of this study is to compare the clinical effects after between modified Widman flap and modified flap in periodontal patients. Ninety six molar area teeth of 9 patients were used. One of sextants performed a modified Widman flap, while the other side performed a modified flap. After initial periodontal therapy, the following measurements prior to surgery(baseline) were taken : pocket depth, gingival recession, clinical attachment level, tooth mobility, bleeding on probing. Also these measurements were taken at 4 weeks, 8weeks, and 12 weeks after surgery. Significant decrease of pocket depth was shown in both techniques, and the degree of decrease was significant in modified flap than modified Widman flap at 12 weeks. Significant increase of gingival recession was shown in both techniques, and the degree of increase was significant in modified Widman flap than modified flap at 4 weeks, 8 weeks, and 12 weeks. Significant attachment gain was shown in both techniques, and the degree of increase was significant in modified flap than modified Widman flap at 4 weeks, 8 weeks, and 12 weeks. Significant increase of tooth mobility was shown in both techniques at 4 weeks, but the decrease of tooth mobility was shown at 12 weeks. Greater decrease of bleeding on probing was shown in both techniques at 4 weeks. Modified flap was better than modified Widman flap in the decrease of gingival recession and the attachment gain. These results indicate that modified flap operation is better than modified Widman flap operation in the effect of periodontal treatment.

• Journal of the Korean Mathematical Society
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• v.38 no.1
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• pp.49-59
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• 2001

In this paper we introduce the modified conditional Yeh-Wiener integral. To do so, we first treat the modified Yeh-Wiener integral. And then we obtain the simple formula for the modified conditional Yeh-Wiener integral and valuate the modified conditional Yeh-Wiener integral for certain functional using the simple formula obtained. Here we consider the functional using the simple formula obtained. Here we consider the functional on a set of continuous functions which are defined on various regions, for example, triangular, parabolic and circular regions.

• Clinics in Shoulder and Elbow
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• v.1 no.2
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• pp.180-185
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• 1998

There has been considerable controversy as to the treatment method of dislocation of the acromioclavicular joint, so various operative treatment modalities have been suggested. We analyzed the results of 40 patients with acromio­clavicular dislocation, in whom twenty patients were treated by modified Phemister method and 20 patients by modified Weaver-Dunn method above follow-up two years. The purpose of this study was to compare the clinical results of two operative methods. According to Weitzman criteriae for clinical results, 12 cases were excellent, six cases good and two cases fair in modified Phemister method. But in modified Weaver-Dunn method, ten cases were excellent, eight cases good, one case fair and one case poor. In radiological result, coracoclavicular distance was measured at preoperative, postoperative and last follow-up period. The modified Phemister method was 6.lmm, 1.5mm and 2.4mm respectively, and the modified Weaver-Dunn method 7.8mm, 2.lmm and 2.5mm respectively. The complications were two cases of heterotopic ossification, one case of inadequate fixation and one case of K-wire breakage in modified Phemister method, and two cases of early fixation loss and one case of heterotopic ossification in modified Weaver-Dunn method. We obtained that the clinical, functional and radiological results showed no significant difference in two methods. The modified Phemister method was effective treatment for old patients in acute injuries due to short operation time and simple technique. The modified Weaver-Dunn method, as a reconstructive operation that reduces various complications for young and active male patients, was also good for getting the stability of coraco­clavicular ligament through clavicular bony union.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.55-59
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• 2009

The epoxy resin without hardener can harden by a ring-opening reaction in the presence of the alkalies produced by the hydration of cement in epoxy-modified mortars and concretes. This paper investigates the effect of curing conditions on the strength improvement of polymer-modified mortars using bisphenol A-type epoxy resin without hardener. The polymer-modified mortars using epoxy resin are prepared with various polymer-cement ratios, and subjected to ideal, water, dry and heat cures. In the heat cure, the epoxy-modified mortars are sealed or unsealed with a PVDC (polyvinylidene chloride) film. The epoxy-modified mortars are tested for flexural and compressive strengths at desired curing methods. The microstructures of the epoxy-modified mortars are also observed by scanning electron microscope. The effects of curing conditions on the strength development of the epoxy-modified mortars are examined. From the test results, the marked effectiveness of the heat cure under the PVDC film sealing against the development of the strength of the epoxy-modified mortar without the hardener is recognized. The flexural and compressive strengths of 7-day-90℃ heat-cured, PVDC film-sealed epoxy-modified mortars without hardener reach 7 to 17MPa and 24 to 44MPa respectively, and are two to three times of Unmodified mortar. Such high strength development of the epoxy-modified mortars may be achieved by the dense microstructure formation by cement hydrates and the hardening of the epoxy resin in the mortars.

• Communications of the Korean Mathematical Society
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• v.16 no.4
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• pp.627-635
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• 2001

In this paper, we first introduce the modified Yeh-Wiener integral and then consider the modified conditional Yeh-Wiener integral. Here we use the space of continuous functions on a different region which was discussed before. We also evaluate some modified conditional Yeh-Wiener integral with examples using the simple formula for the modified conditional Yeh-Wiener integral.

• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.816-820
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• 2001

A new copper hexacyanoferrate modified electrode was constructed by mechanical immobilization. The modified electrode was characterised by cyclic voltammetric experiments. Electrocatalytic oxidation of glutathione was effective at the modified electrode at a significantly reduced overpotential and at broader pH range. The modified electrode shows a stable and linear response in the concentration range of 9 ${\times}$10-5 to 9.9 ${\times}$10-4M with a correlation coefficient of 0.9995. The modified electrode exhibits excellent stability, reproducibility and rapid response and can be used in flow injection analysis for the determination of glutathione.

• International Journal of Highway Engineering
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• v.14 no.5
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• pp.47-55
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• 2012

PURPOSES: SUPERPAVE binder grade tests including Multiple Stress Creep and Recovery(MSCR) test are applied to evaluate rheological properties of four polymer modified binders. METHODS: To evaluate grade of four modified binders, PG testing protocols, such as DSR, BBR and MSCR are employed. RESULTS: It is observed that MSCR test shows different performance grades especially on modified binders. Both DMP and EG binder show similar high temperature performance to SBS 5% modified binder. CONCLUSIONS: Binder Grading system in Korea need to be reviewed to properly reflect the performnace of modified binders. The binders modified with DMP and EG can be possible alternatives SBS 5% modified binder considering its performance and cost.

• Toxicological Research
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• v.17
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• pp.185-188
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• 2001

Genetically modified foods and food additives are derived from organisms that have been inserted foreign genetic materials by recombinant DNA techniques to improve the quality or any other pur-poses. The problems such as toxicity, allergenicity and antibiotics resistance in the safety of genetically modified foods are usually concerned. In Korea, the safety of foods is ensured by the Food Sanitation Act. Although there is no specific provision regarding the genetically modified foods in it, any foods that might cause negative effect(s) on public health or human life are prohibited to sell in the market. In order to systematically evaluate safety of genetically modified foods, the Korea Food and Drug Administration (KFDA) promulgated "Guidelines regarding review of safety assessment data for genetically modified foods and food additives (KFDA Notification 1999-46)". The objectives of these guidelines are to ensure safety of genetically modified foods and food additives. In order to evaluate the safety of genetically modified foods. KFDA operates a special expert committee composed by experts from government, universities, research institutes. and consumer's unions. Recently. manufacturers and consumers are interested in the issues on safety and labeling of genetically modified foods, because of increment of imported genetically modified crops and processed foods. Since government and consumers unions have different viewpoints, their positions regarding the issue are different each other. Therefore, the regulation of labeling on genetically modified foods is prepared and should be enforced at July 2000 in Korea. in Korea.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.233-243
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• 2012

This study was performed to determine the quality characteristics of Jeungpyun with added modified starch. The addition of modified starch did not change the pH level of the samples, but it did increase the volume. The b-value of Jeungpyun with 3% modified starch was significantly lower than that of the control group. The addition of 3% modified starch also significantly increased the hardness, adhesiveness, gumminess and chewiness of the experimental group over the control group. In the test of sensory characteristics, the cell size of Jeungpyun with 2 and 3% modified starch was larger than that of the control group. Cell uniformity of Jeungpyun with 2% modified starch was lower than that of the control group. The hardness of Jeungpyun with modified starch was significantly higher than that of the control group. In the test of taste preference, Jeungpyun with modified starch beat the control group substantially. The quality of Jeungpyun with 1 and 3% modified starch showed a higher overall score than that of the control group.