• International Journal of Highway Engineering
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• v.10 no.4
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• pp.281-292
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• 2008

In Korea-LTPP(Long Tenn Pavement Performance) project, the full depth asphalt pavement test sections are constructed on the national highway to evaluate the structural capacity of asphalt pavement reinforced with glass fiber. Truck loading test and FWD test were performed to measure the structural capacity of test sections. Test results showed that the reinforcement of glass fiber installed at between surface and intermediate asphalt layer decreased the strain at the bottom of surface layer and moved up the stress neutral axis in asphalt layer. As a result, the tensile stress was developed at the bottom of intermediate asphalt layer of reinforced asphalt pavement, while the compressive stress was developed at the bottom of intermediate asphalt layer of unreinforced asphalt pavement. On the other hand, the tensile strain at the bottom of asphalt base layer didn't show a difference between glass fiber reinforced and unreinforced pavements. From the FWD test, it was shown that the surface deflection of asphalt pavement reinforced with glass fiber decreased 24 percents comparing to that of unreinforced asphalt pavement. This shows that the reinforcement with glass fiber appears to improve the rutting resistance of asphalt pavement.

• Korean Journal of Veterinary Pathology
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• v.3 no.2
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• pp.87-91
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• 1999

The present study was undertaken to compare the variation on serum biochemical values by storage in the rats. Sera were prepared from 30 Sprague-Dawley rats of each sex. 5 aliquots from each serum were placed in a -80$^{\circ}C$ freezer with the exception of I aliquots which was analyzed immediately. The analysis was performed on the following months; 1, 2, 3, 6, and 12 months after freezing. The parameters measured) were aspartate aminotransferase(AST), alanine aminotransferase(ALT), alkaline phosphatase(ALP), blood urea nitrogen(BUN) creatinine(CRE), glucose(GLU), total cholesterol(TCHO), triglyceride (TG), total protein(TP), albumin(ALB), total bilirubin(TBIL), calcium(Ca$\^$＋＋/), inorganic phosphorus(IP), creatine kinase (CK), phospholipid(PL), albumin-globulin ratio(A/G), sodium(Na$\^$＋/), potassium(K$\^$＋/), and chloride(Cl$\^$－/) The statistical analysis with Repeated Measures ANOVA, did not show statistical significance in the parameters of AST, ALT, BUN, TG, CK, A/G, Na$\^$＋/ of 1 month freezed sera, in those of AST, TG, CK, K$\^$＋/) of 2 month freezed sera, in those of AST, ALT, BUN, CRE, TCHO, TP, TBIL, CK, PL, Na$\^$＋/), K$\^$＋/), Ct on month fteezed sera, in those of Cl$\^$－/ of 6 month fteezed sera, and in those of ALT, TG, ALB of 12 month freezed sera in male SD rats. On the other hand, it did not show statistical significance in the parameters of AST, ALT, ALP, BUN, GLU, TCHO, TG, TBIL, CK, PL, A/G, Na$\^$＋/ of 1 month freezed sera, in those of AST, TCHO of 2 month freezed sera, in those of AST, BUN, CRE, TCHO, TP, TBIL, CK, PL of 3 month freezed sera, in those of TCHO, IP, PL of 6 month freezed sera, and in those of ALB of 12 month freezed sera in female SD rats. On the basis of the results, although there are some statistical variations in the biochemical values of the sera, it is suggested that if sera are analysed at the same time before 12 months storage in a －80 $^{\circ}C$ freezer, the storing time does not affect the biochemical evaluation of the sera in SD rats.

• Journal of the Korean Wood Science and Technology
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• v.43 no.4
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• pp.478-485
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• 2015

The aim of this study is to analyze the combustion and thermal properties in order to establish baseline data for the fire safety evaluation of domestic timbers. The combustion properties such as heat release rate, total heat release, gas yield, and mass loss were analyzed by the method of cone calorimeter test and thermogravimetry (TGA). Thermal decomposition temperatures of the specimens by TGA were recorded as $359.83^{\circ}C$ for White pine, $359.80^{\circ}C$ for Red-Leaved Hornbeam, $363.14^{\circ}C$ for Carolina poplar, $358.59^{\circ}C$ for Konara oak, and $362.11^{\circ}C$ Sargent cherry. Red-Leaved Hornbeam showed the highest value of heat release rate, but, Carolina poplar wood showed the lowest value. In case of the total heat release, Red-Leaved Hornbeam wood showed the highest value and Carolina poplar wood showed the lowest one. The gas analysis results showed that Sargent cherry wood had the lowest value of 0.021, and Konara oak had the highest at 0.031 in the $CO/CO_2$. The minimum value of mass reduction was recorded as 87.57% for Sargent cherry, but, on the other hand, it was 95.03% for Konara oak. There was a correlation between the gas generation of CO and $CO_2$, and combustion behavior of woods. These results are expected to be usful for providing a fundamental guideline with the fire safety of wood use in interior applications.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.1
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• pp.73-83
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• 1997

Most of the materials used in various industrial fields and also in our daily life are multi-component materials or composite materials, and it is well known that there are many cases where adhesion between the constituents within the bonded systems plays an important role. There are various types of performance evaluation tests for the bonded materials, among which tests for evaluating the bond performance under various conditions may be regarded as the most interesting ones for those engaged in work related to adhesion. I have studied on the mechanism of adhesion form the rheological standpoint with my colleagues, including some students from Korea, and I am very happy to be able to have a talk on some of our research works. In Japan, the so-called "adhesives" are usually classified into two categories;adhesives and pressure sensitive adhesives (PSA). Adhesives are the materials which solidify after bonding and are after used as the structural adhesives because the adhesive strength is comparatively strong. On the other hand, the pressure sensitive adhesives never solidify and are used as PSA tapes, labels or decals. About the adhesives, we have examined the dependence of adhesive strength(shear, tensile, peel) upon both temperature and rate of deformation, and found out some empirical rules which are applicable to most of the adhesive systems. We have also developed a simplified theory of adhesion, which is deseribed in terms of mechanical equivalent mode1 and a few failure criteria. Although some of the common rules can be accounted for according to this theory, it must be pointed out that a fracture mechanical approach ms inevitable especially in the region where the meehanical relaxation time of the adhesive is extremely large [W. W. Lim and H. Mizumachi]. About the pressure sensitive adhesives, we have studied on the PSA performance (peel, tack, holding power) as a function of both the viscoelastic properties and surface chemical properties of the materials, and found out some rules, and again we have developed a theory which deseribes the mechanism. And in addition, we have studied on the miscibility between linear polymers and oligomers, because PSA is generally manufactured by blending gums and tackifier resins. Many phase diagrams have been found and some of them have been analyzed on thermodynamic basis, and it became evident that the miscibility is a very important factor in PSA [H. J. Kin and H. Mizumachi]. In this presentation, I want to emphasize the fact that the adhesion performance is closely related to the structure/property of the adhesives.adhesives.

• Journal of the Korean Society for Nondestructive Testing
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• v.19 no.6
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• pp.433-438
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• 1999

Magneto-acoustic emission (MAE) energy and hardness were measured in the reactor pressure vessel steel (SA508 Steel) for the various neutron fluence, irradiated dose up to $10^{18}n/cm^2$. The hardness was nearly a constant up to $10^{16}n/cm^2$, but it was rapidly increased with an increase of the neutron irradiation above $10^{17}n/cm^2$. It may be considered that the increase of hardness is due to the hindrance of dislocation motion induced defect clusters by irradiation. On the other hand. the MAE energy was slowly decreased as the neutron irradiation increased up to $10^{16}n/cm^2$ and it was rapidly decreased with an increase of the neutron irradiation above $10^{17}n/cm^2$. The decrease of the MAE energy may be considered as an increase of the defect clusters which is very sensitive to the $90^{\circ}$ domain wall motion. Furthermore, the change of MAE energy and hardness had nearly a linear relationship. but the change of MAE energy was more significant than the change of the hardness. Therefore, MAE may be considered as a very useful technique for the nondestructive evaluation of irradiation damage.

• Korean Journal of Organic Agriculture
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• v.27 no.4
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• pp.453-461
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• 2019

The purpose of this study was to evaluate the mixed treatment of compost tea and amino acid liquid fertilizer as a substitute of oil cake for the organic cultivation of maize in Goesan, Chungbuk province. As a result, nitrogen, phosphoric acid, potassium, calcium and magnesium contents of each organic fertilizer were in the order of oil cake > amino acid fertilizer > compost tea. Each of these organic fertilizers had little influence on the change of soil chemical. Individual treatment of amino acid fertilizer and oil cake for weight of an ear as well as all individual treatments for the fresh weight of 100 kernels showed significant increase, compared to the untreated control. For the corn yield of merchantable quality, each treatment of compost tea, amino acid liquid fertilizer and oil cake increased higher 3.9, 5.4 and 5.9% than untreated control, respectively. On the other hand, as a result of mixed treatment of amino acid fertilizer and compost tea, the change of soil chemical property was insignificant. The mixed treatment, Nonetheless, showed significant increase for stem height to 1st ear, grain setting length in an ear, weight of an ear, and fresh weight of 100 kernels, compared to the oil cake as a control. After all, the corn yield of merchantable quality produced by the mixed treatment was 3.9% higher than the control. Therefore, our study would be considered that the mixed treatment of amino acid and compost tea is one of organic materials that can replace oil-cake in maize.

• Journal of Korean Physical Therapy Science
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• v.10 no.1
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• pp.47-57
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• 2003

The purpose of this study was to evaluate the problem on activities of daily living ; the problem which spinal cord injured patients have when they adapt in daily living ; Subjects were 113 members who used the hospital which is located in Kwangju-city from November 20, 2001 to May 20, 2002. The evaluation of the ADL was performed according to MBI and collected data were statistically analysed by SPSS PC for paired Chi-square test T-test, One way ANOVA and Duncan's post-hoc test. The result's were as follows; 1. Modified Barthel Index average mark was $63.77{\pm}33.60$ points and MBI score distribution according to characteristics of injury is as following. 1) A patient who had long duration of injury, small injury region, incomplete paralysis in paralysis degree, paraplegia in paralysis type got high MBI score as statistical and significantly(p<0.05). 2. Society adaptation state by characteristics of spinal cord injured is an following. 1) After lapse of time of disease, a patient who is injured for a long term present surrounding environmental problem, a patient who is injured for a short term shows psychological problem. In society activity, as lapse of time of disease is long, patient did many hobby activity and same private club, on the other hand as lapse of time of diseases is short, the others appeared high and significantly as statistical(p<0.01). 2) In society activity by injury region, cervical injury and thoracic injury did more hobby activity than lumbar injury and in lumbar injury same private club or religion life appeared higher than thoracic injury of cervical injury significantly as statistical(p<0.01). 3) In walk method by paralysis degree Complete paralysis had more wheelchair life than incomplete paralysis(p<0.01). 4) In serious problem by paralysis type psychological problem in quadriplegia and surrounding environmental problem in paraplegia appeared high and significantly as statistical(p<0.01). 3. In society adaptation state by MBI score difference between variables appeared but it wasn't significantly.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.476-484
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• 2005

This paper is to evaluate rather correctly $C^{14}$ ingestion dose that inhabitants around PWR plants can receive, and draw how to apply TF(Transfer Factor) to evaluate dose by the ingestion of animal products. For this, in this paper, dose assessment and analysis about existing materials related to TF were carried out, and the methodology to present TF was based on dose assessment and analysis result. The ingestion dose calculated using TFs presented by CSA and KEPRI was high or equal compared with SAM(Specific Activity Model) which is the most conservative, on the other hand, TFs given by NEC did not consider the effect according to volume change of animal at all, Therefore, it is judged that models used in the existing codes to asses the $C^{14}$ concentration into animal products must be improved to apply fundamentally hybrid model using transfer factors, that transfer factor on each animal products have to be developed through experiment for applying to our county.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.5
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• pp.260-268
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• 2017

In this study, wind characteristics of a shipping container were investigated through the wind tunnel test (high-frequency force balance test), and damage occurrence velocities of various containers with weights were evaluated based on results of the wind tunnel tests. As a result, mean wind force coefficients acting on containers in x-direction increased in the order of 12ft, 20ft, 40ft and 40ft high cube. On the other hand, mean wind force coefficients at y-direction increased in the order of 40ft high cube, 40ft, 20ft and 12ft. It was suggested that the shear layer separated from the corner of windward surface of the container is reattached on the sides of it, and then the mean wind force coefficient is weaker. As a result of the damage occurrence velocity on containers with weights, it was found that the probability of occurrence of sliding is higher rather than that of overturning. Further, the most unfavorable container was 40ft high cube, and the sliding and overturning occurrence velocities were 20.4 m/s and 26.8 m/s, respectively. Furthermore, the regression formula for sliding and overturing occurrence velocitys were proposed based on the results of relationship between weights of containers and damage occurrence velocities. These results are expected to be useful in establishing a guideline for external force estimation acting on container securing equipment and stacking way.

• Journal of Korean society of Dental Hygiene
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• v.9 no.2
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• pp.147-163
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• 2009

This study was attempted in order to look into 'Assist work' as to Implant system which dental hygienists perform in a clinical field. Subjects of this research were 362 dental hygienists who work at general hospital, University hospital, dental hospital, and dental clinics located in Seoul, Kyeong-gi, In-chon, and Jeon-buk area. As to research tool, we produced questionnaire which was comprised of the total 25 items regarding 3 of general features (age, career of dental hygienist, and personality), 6 of implant system assist work, 3 of Informed consent before surgery, 6 of preoperative preparation and maintenance related business, and 7 items related to postoperative maintenance. By using SPSS program, collected data was analyzed. Results of analysis in this study were as follow; 1. As to implant related education, dental hygienists' experience of education was high as 77.7%, and the people who is needed more education was 86.3%. Consequently, dental hygienists' concern about the implant related education was very high. 2. It was observed that most of informed consent making approvement by announcement to the surgical operation was made by dental hygienist before implant as 95%. 3. Over 80% of dental hygienists performed acquisition of cleanliness technology, motivation, back up articles preparation, treatment area arrangement, and etc. which we can check by preoperative maintenance items. In particular, response about the motivation was very high as more than 90%. 4. When performing an operation, in the case of disinfecting finger was low for 53.9% and the method was mainly washing with drug solution, and gown sterilization was performed only in 52.2%. Therefore education regarding disinfection was urgently needed. 5. Significance of education could be known that answers of hygienists experienced education appeared highly in items of maintenance method and there was statistically significant difference(p<0.05). 6. In case that assist work were 21cases or greater, agitation measurement was the most many performed in 68.9% and difference was showed up significantly(p<0.001). 7. Evaluation about periodontal tissue was high in dental hygienists who had experienced education and also there was statistically significant difference. In conclusion, assist work of dental hygienists was very comprehensive when implant surgery was performed, and all of items excluding hand disinfection or gown disinfection were highly showed up in most of hygienists. However, since there is the limit that we didn't investigate the quality of performing contents. It is considered that further study regarding the content has to be progressed for supporting this result in the future.