• Journal of Conservation Science
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• v.31 no.1
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• pp.37-46
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• 2015

In the case of adhesives & restoration agents currently being used for the preservation treatment of ceramics and earthenware, epoxy type, cellulose type and cellulose type are mainly being used. However, they are showing various problems such as re-detachment from severe contraction, color change from yellowing, work inconvenience of staining on tools and hand during usage and irreversibility. For the purpose of solving the issues of yellowing and irreversibility of epoxy resin being used to restore ceramics, urethane synthetic resin with low yellowing excellent reversibility has been developed in this study. The adhesive strength of urethane resin that has been developed has excellent properties with 2.07MPa for undiluted solution, which is 1.5 times higher than that of existing material EPO-$TEK301^{(R)}$ 1.21MPa. The result of workability measurement showed that the wear rate of urethane resin (in Talc 50wt%) was 1.09%, which was somewhat higher than that of existing material Quick $Wood^{(R)}$ (1.02%). In addition, its wear rate is two times higher than that of $EPO-TEK301^{(R)}$ (0.41%) and $L30^{(R)}$ (0.39%), thereby showing an advantage in its forming process compared to existing materials. As for the advantage of urethane resin of reversibility experiment, 12 hours after acetone, ethyl alcohol deposition, urethane resin and filler talc were dissolved 100% while showing powdering phenomenon. Compared to 0% reversibility of existing epoxy resin, it has much superior reversibility. The result of UV rays experiment to evaluate its durability showed that ${\Delta}E^*ab$ color change value based on undiluted solution of urethane resin was 2.76 before & after UV rays exposure, which was a decrease by about 7-20 times compared to that of existing resin, thereby minimizing the issue of heterogeneity.

• Journal of Bio-Environment Control
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• v.14 no.2
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• pp.83-88
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• 2005

A study was conducted on three pollination methods on oriental melon(sageageol-ggul) grafting with pumpkin(seongjutozoa) for the labor-saving and to improve fruit set. Fruit weight, flesh thickness and fruit setting rate of oriental melon were greater in growth regulators treatment than those of pollinated by bees. Sugar content and hardness of fruits pollinated by bees were higher than those of by growth regulators. From the last ten days of the February to the first ten days of the March, fruit setting rate was $95\%$ in fruit setting growth regulators, whereas it was $46\%$ and $45\%$ in pollinated by honey and bumble bee, respectively. After the middle of March, the percentage of fruit setting was >$98\%$ in all the pollination methods. The cultivation under plastic houses of oriental melon, suitable fruiting time far the pollination by bees was decided after middle days of the March. Chromaticity and especially the value of 'a' of fruit of oriental melon pollinated by bees were higher than those of growth regulators. The percentage of fermented fruits of bee pollinated and growth regulators treated was $6.7\~9.1\%\;and\;28.1\%$, respectively. The weight of 100 seeds of bees pollinated were higher than that of growth regulators. The more increased the weight of 100 seeds the less appeared the rate of fermented fruits. The percentage of marketable fruits of the honey and bumble bee pollinated and that of growth regulators treated was $82\%,\;80.3\%\;and\;62.5\%$, respectively. The decreasing rate of fruit weight during storage of bees pollinated was less than those of growth regulators. In these results, the introduction of honey bee and bumble bee for the pollination of oriental melon was able to labor-saving of fruit set and increase of fruit quality.

• Restorative Dentistry and Endodontics
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• v.35 no.5
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• pp.380-386
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• 2010

Objectives: The introduction of nickel-titanium alloy endodontic instruments has greatly simplified shaping the root canal systems. However, these new instruments have several unexpected disadvantages. One of these is tendency to screw into the canal. In this study, the influence of taper on the screw-in effect of the Ni-Ti rotary instrument were evaluated. Materials and Methods: A total of 20 simulated root canals with an S-shaped curvature in clear resin blocks were divided into two groups. ProFile .02, .04, .06 (Dentsply-Maillefer) and GT rotary files .08, .10, .12 (Dentsply) were used in Profile group, and K3 .04, .06, .08, .10, and .12 (SybronEndo, Glendora) were used in K3 group. Files were used with a single pecking motion at a constant speed of 300 rpm. A special device was made to measure the force of screw-in effect. A dynamometer of the device recorded the screwin force during simulated canal preparation and the recorded data was stored in computer with designed software. The data were subjected to one-way ANOVA and Tukey's multiple range test for post-hoc test. p value of less than 0.05 was regarded significant. Results: The more tapered instruments generated more screw-in forces in Profile group (p < 0.05). In K3 group, 0.08, 0.10. and 0.12 tapered instruments showed more screw-in force than 0.04 tapered one, and 0.08 and 0.12 tapered instruments showed more screw-in force than 0.06 tapered one (p < 0.05). Conclusions: The more tapered instruments seems to produce more screw-in force. To avoid this screw-in force during instrumentation, more attention may be needed when using more tapered instruments.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2003.12a
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• pp.543-559
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• 2003

The information drive of the businesses requires new alternatives in that the promotion of business efficiency through information process technologies ends up conflicting with the protection of information human rights on laborers’side. Nevertheless, apathy on information protection has a tendency to be distorted by the efficiency of the businesses. Should the capital and mass media warn economic red lights, political circles with uneasiness would ignore the significance of information protection on the behalf of business efficiency. Therefore, the importance of information protection is considered a smaller interest than that of business efficiency with the infringements of human rights on laborers’side arising. Informatization of the businesses along with the developments of information process technologies has enabled the management to monitor and control the behaviors of laborers. This new problem needs to establish both information protection mechanism and institutional devices to regulate those labor controls. The security of business activity without human rights infringement warrants both basic rights of the public and spirit of the Constitution. The study suggests the establishment and revision of laws suitable to the period of information human rights. On top of that, the establishment of the basic law for information protection of individuals’with the common principle that integrates the related laws and rules on-off line is needed. This will warrant the active participation of labor unions and create specific alternatives for information protection.

• Restorative Dentistry and Endodontics
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• v.32 no.4
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• pp.343-355
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• 2007

The objectives of this study was to evaluate the durability of 4 resin cements by means of microtensile bond strength test combined with thermocycling method and fractographic FE-SEM analysis. Experimental groups were prepared according to thermocycling (0, 1,000, 5,000) and the kind of resin cements, those were Variolink II, Multilink, Panavia F 2.0, Rely X Unicem. Flat dentin surfaces were created on mid-coronal dentin of extracted third molars. Then fresh dentin surface was grounded with 320-grit silicon carbide abrasive papers to create uniform smear layers. Indirect composite block (Tescera, Bisco Inc., Schaumburg, IL, USA) was fabricated ($12\;{\times}\;12\;{\times}\;6\;mm^3$). It's surface for bonding to tooth was grounded with silicon carbide abrasive papers from 180- to 600-grit serially, then sandblasted witk $20\;-\;50\;{\mu}m$ alumina oxide. According to each manufacturer's instruction, dentin surface was treated and indirect composite block was luted on it using each resin cement. For Rely X Unicem, dentin surface was not treated. The bonded tooth-resin block were stored in distilled water at $37^{\circ}C$ for 24 hours. After thermocycling, the bonded tooth-resin block was sectioned occluso-gingivally to 1.0 mm thick serial slabs using all Isomet slow-speed saw (Isomet, Buehler Ltd, Lake Bluff, IL, USA). These sectioned slabs were further sectioned to $1.0\;{\times}\;1.0\;mm^2$ composite-dentin beams. The specimens were tested with universal testing machine (EZ-Test, Shimadzu, Japan) at a crosshead speed of 1.0 mm/min with maximum load of 500 N. The data was analyzed using one-way ANOVA and Duncan's multiple comparison test at $p\;{\leq}\;0.05$ level. Within the limited results, we conclude as follows; 1. The bond strength of Variolink II was evaluated the highest among experimental groups and was significantly decreased after 1,000 thermocycling (p < 0.05). 2. The bond strength of Multilink was more affected by thermocycling than the other experimental groups and significantly decreased after 1,000 thermocycling (p < 0.05). 3. Panavia F 2.0 and Rely X Unicem showed the gradually decreased tendency of microtensile bond strength according to thermocycling but there was no significant difference (p > 0.05). 4. Adhesive based-resin cements showed lower bond strength with or without thermocycling than composite based-resin cements. 5. Variolink II & Multilink showed high bond strength and mixed failure, which was occurred with a thin layer of luting resin cement before thermocycling and gradually increased adhesive failure along the dentin surface after thermocycling. The bonding performance of resin cement can be affected by application procedure and chemical composition. Composite based-resin cement showed higher bond strength and durability than adhesive based-resin cement.

• Korean Journal of Poultry Science
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• v.42 no.3
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• pp.223-230
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• 2015

Eggs are an important source of protein for the human diet. Consumers want fresher, more delicious and more sanitary eggs. In Korea, the Shell Egg Grading system (EGS) was employed in 2001. The portion of graded shell eggs has increased every year, but graded shell eggs account for only 6% of all eggs. The EGS should satisfy producers, distributors and consumers. However, the EGS does not have an official function because of many problems. Consumers cannot select various graded shell eggs in the market, and producers do not receive enough profit even though they produce top-quality graded shell eggs. There are few studies on the EGS, Therefore, this study was performed to improve the EGS. We surveyed the EGS, GP Centers and farmers. Large companies (farmers) are more satisfied than small companies with the EGS. There was a high tendency for the companies (farmers) that are not involved with the EGS to think that graded and ungraded shell eggs are similar, in contrast to the companies (farmers) connected to the EGS. We should have to change the grading system of grade shell eggs, establish of the cold chain system, change of the law for the school meals, minimize payment for the grading shell eggs for developing EGS. Based on this study, the egg industry can benefit through the improvement of the EGS.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.231-243
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• 2014

In this study, the potential of biomass, which is generated from oil palm cultivation and crude palm oil (CPO) production of Indonesia was assessed in the aspect of energy content. The types of oil palm biomass were classified on the basis of the cultivation stage and the CPO production stage. In the cultivation stage, biomass is considered to be produced from its' root, trunk and frond. Other possible biomass resources such as empty fruit bunch (EFB), palm kernel shell (PKS) and fiber were included in the CPO production stage. As results, total biomass from damaged plantation area of Indonesia was estimated to be annually from 3 million to 16 million tons in 2011. From CPO mills, approximately 49 million tons/yr of biomass residues were estimated to be annually occurred. Their total energy content from each biomass source in cultivation stage was analyzed to be from 593,000 to 3,197,000 TOEs in terms of gross calorific value. In the case of CPO mills, around 22.7 million TOEs was estimated to be potential energy producible by biomass based on gross calorific value of dry basis. If moisture content considered, net calorific value was analyzed to be decreased to 16.3 million TOEs. Based on the results, the total energy contents of all oil palm biomass were estimated to be up to 25,919,000 TOE in terms of gross calorific value. CPO : Crude Palm Oil, EFB : Empty Fruit Bunch, FFB: Fresh Fruit Bunch, PKS : Palm Kernel Shell, OPF : Oil Palm Frond, PKOC : Palm Kernel Oil Cake, ISPO : Indonesia Sustainable Palm Oil Commission, TOE : Tone of Oil Equivalent.

• Journal of Chest Surgery
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• v.39 no.3 s.260
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• pp.220-225
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• 2006

Background: Spontaneous pneumomediastinum is an uncommon, benign, self-limited disorders that usually occurs in young adults without any apparent precipitating factors or disease. The purpose of this study was to review our experience in dealing with this entity and describe a reasonable course of assessment and management. Material and Method: A retrospective case series was conducted to identify adults patients with SPM who were diagnosed and treated in a single institution between 2001 and 2005. Result: Fifteen patients were identified who included 14 men and 1 women with a mean age of 26 years. Presenting symptoms were chest pain in 12 patients ($80\%$), dyspnea in 5 patients ($33\%$), and throat discomfort in 4 patients ($26\%$). Two cases were associated with use of inhalational drugs and 3 cases were associated with exercise. The predisposing factors were asthma, excessive exercise, and vomiting in spontaneous pneumomediastinum. The physical findings were subcutaneous emphysema in 10 patients ($77\%$). Chest radiography and computerized tomography were the diagnostic methods in all cases with CT scan revealing six cases with associated pulmonary abnormalities. Esophagogram and flexible bronchoscopy were selectively used. Fifteen patients ($100\%$) were admitted to the hospital. Their mean hospital stay was 3 days. All patients were conservatively treated. In a follow-up of 3 years no complications or recurrences were observed. Conclusion: Most simple spontaneous pneumomediastinum cases were benign diseases and most of them ($77\%$) had shown typical chest pain, dyspnea and subcutaneous emphysema. Inhalational drug use was not a major cause of SPM; however, increased use of bronchoinhalers was a suspicious cause of SPM.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.257-262
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• 2013

This study investigates the effect of fermentable carbohydrate on the concentration of odorous compounds in pig slurry. Four types of pig diet were studied: control, peanut hull (crude fiber 29.87, NDF 44.02%), golden fiber (crude fiber 48.77, NDF 65.88%), and almond hull (crude fiber 44.30, NDF 64.44%). Pigs (average BW 37.0 kg) were fed diets that met the Korean Feeding Standard (2012) and their excreta samples were collected from the slurry pits. Levels of volatile organic compounds (phenols and indoles) and volatile fatty acids were analyzed by gas chromatography. Phenol level was the lowest (p<0.05) in golden fiber (33.26 ppm) group and the highest in control (97.29 ppm). The concentration of indoles in the peanut hull (1.27 ppm), almond hull (1.20 ppm), and golden fiber (1.02 ppm) groups was lower (p < 0.05) than that of control (1.79 ppm). Levels of short chain fatty acid (SCFA) were lower (p < 0.05) in golden fiber (1,319 ppm) and almond hull (1,433 ppm) groups than in control (1,893 ppm). Concentration of branched chain fatty acid (BCFA) in the golden fiber group (74 ppm) was lower (p < 0.05) than that of control (98 ppm). Taken together, the concentration levels of phenols, indoles, and VFAs decreased on addition of peanut hull, golden fiber or almond hull to the diet, suggesting that fermentable carbohydrate may contribute to reducing odorous compounds in pig slurry.

• Journal of Food Hygiene and Safety
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• v.29 no.2
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• pp.158-163
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• 2014

In this study, two commercial PCR and ELISA test kits were examined for identification of eight animal species (beef, pork, chicken, duck, turkey, goat, lamb, and horse) from raw meat and meat products in Korea. The detection limit in RAW meat ELISA kit$^{(R)}$ on three types of meat samples blended with beef, pork and chicken, demonstrated that all meat species were differentiable down to 0.2%. RAW meat ELISA kit$^{(R)}$ on animal species resulted in differentiation rate of 94.5% for beef, 93.3% for pork, 90% for lamb, and 100% for chicken, duck, turkey, goat, and horse. In contrast, Powercheck Animal Species ID PCR kit$^{TM}$ resulted in 100% specificity at 0.05% limit of detection for all meat species. The detection limit of Cooked Meat ELISA kit$^{(R)}$ on mixed meat samples heat-treated with different temperatures and times, resulted in 0.1% for all heat-treated mixed meat except for chicken at 1.0%. Additionally, ELISA kit on sixty meat products resulted in specificity of 31.8% for ham, 13.6% for sausages, and 12.5% for ground processed products, and relatively low rate for more than 2 types of mixed meats. On the contrary, meat species differentiation using PCR kit showed higher percentage than that using ELISA kit$^{(R)}$: 50.0% for ham, 41.7% for sausages, and 28.6% for ground processed meat. Futhermore, PCR kit on 54 dried beef meats detected pork genes in 13 products whereas ELISA kit showed negative results for all products. Hence, the possibility of cross-contamination during manufacturing process was investigated, and it was found that identical tumblers, straining trays, cutters and dryers were used in both beef and pork jerky production line, suggesting the inclusion of pork genes in beef products due to cross-contamination. In this study, PCR and ELISA test kits were found to be excellent methods for meat species differentiation in raw meat and heat-processed mixed meat. However, lower differentiation rate demonstrated in case of meat processed products raised the possibility of inclusion of other species due to cross-contamination during manufacturing process.