• International Journal of Highway Engineering
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• v.17 no.2
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• pp.55-62
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• 2015

Cracking is an inevitable fact of asphalt concrete pavements and plays a major role in pavement deterioration. Pavement cracking is one of the main factors determining the frequency and method of repair. Cracks can be treated with a number of preventative maintenance actions, including overlay surface treatments such as slurry sealing, crack sealing, or crack filling. Pavement cracks can show up as one or all of the following types: transverse, longitudinal, fatigue, block, reflective, edge, and slippage. Crack sealing is a frequently used pavement maintenance treatment because it significantly extends the pavement service life. However, crack sealant often fails prematurely due to a loss of adhesion. Because current test methods are mostly empirical and only provide a qualitative measure of the bond strength, they cannot accurately predict the adhesive failure of the sealant. This study introduces a laboratory test aimed at assessing the bonding of hot-poured crack sealant to the walls of pavement cracks. A pneumatic adhesion tensile testing instrument (PATTI) was adopted to measure the bonding strength of the hot-poured crack sealant as a function of the curing time and temperature. Based on a limited number of test results, the hot-poured crack sealants have very different bonding performances. Therefore, this test method can be proposed as part of a newly developed performance-based standard specification for hot-poured crack sealants for use in the future. PURPOSES : The purpose of this study was to evaluate both the adhesion and failure performance of a crack sealant as a function of its curing time and curing temperature. METHODS: A pneumatic adhesion tensile testing instrument (PATTI) was adopted to measure the adhesion performance of a crack sealant as a function of the curing time and curing temperature. RESULTS: With changes in the curing time, curing temperature, and sealant type, the bond strengths were found to be significantly different. Also, higher bond strengths were measured at lower temperatures. Different sealant types produced completely different bond strengths and failure behaviors. CONCLUSIONS: The bonding strength of an evaluated crack sealant was shown to differ depending on various factors. Two sealant types, which were composed of different raw materials, were shown to perform differently. The newly proposed test offers the possibility of evaluating and differentiating between different crack sealants. Based on alimited number of test results, this test method can be proposed as part of a newly developed performance-based standard specification for crack sealants or as part of a guideline for the selection of hot-poured crack sealant in the future.

• Journal of Sasang Constitutional Medicine
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• v.23 no.3
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• pp.340-350
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• 2011

1. Objectives: This clinical study was conducted to understand the differences between Sasang constitutional types and to identify the physical symptoms presentation specific to each Sasang constitutional type. 2. Methods: In this descriptive study, 2,629 subjects (1,061 Taeeum-type, 683 Soeum-type, 885 Soyang-type) were surveyed between Nov 1, 2007 and Jul 31, 2010. The subjective symptoms experienced by the subjects were collected using a Physical Symptoms questionnaire, and the subjects were interviewed by Sasang specialists who determined the subjects' constitutional type. The data (in crude number and percentage) was analyzed on the general characteristics, Sasang constitutional type, and physical symptoms using the SPSS 17.0 software. The symptomatic presentation in men and women were analyzed on Sasang constitutional distribution using the chi-square test. 3. Results: 1) The physical symptoms specific to each Sasang constitutional type were as follows: 'frequent aphthous lesions in the oral cavity', 'lingering fatigue after sleep', 'headache', 'common cold symptoms presenting as loss of appetite or indigestion', and 'physical deterioration presenting as problems with digestion' in the Soeum type; 'physical deterioration presenting as problems in perspiration' and 'swelling and puffiness' in the Taeeum type; and 'excessive forgetfulness' in the Soyang type. 2) The physical symptoms specific to each Sasang constitutional type in men were as follows: 'Unilateral or bilateral headaches, 'frequent aphthous lesions in the oral cavity', 'common cold symptoms presenting as rhinorrhea or nasal congestion', 'common cold symptoms presenting as loss of appetite or indigestion', and 'physical deterioration presenting as problems with digestion' in the Soeum type; and 'swelling and puffiness' in the Taeeum type. 3) The physical symptoms specific to each Sasang constitutional type in women were as follows: 'common cold symptoms presenting as headaches', 'common cold symptoms presenting as loss of appetite or indigestion', 'physical deterioration presenting as problems with digestion' in the Soeum type; and 'pain in knees', 'redness of eyes', 'dryness of mouth', 'common cold symptoms presenting as coughing', 'physical deterioration presenting as problems in perspiration', 'swelling and puffiness' in the Taeeum type. 4. Conclusions: This study demonstrates that physical symptoms present in constitutional type-specific patterns. Understanding of the personal Sasang constitutional type and systematic, personalized healthcare based on constitutional typology is anticipated to contribute to improved health management strategy.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.5
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• pp.458-463
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• 2010

Since the acoustic nonlinearity is sensitive to the minute variation of material properties, the nonlinear ultrasonic technique(NUT) has been considered as a promising method to evaluate the material degradation or fatigue. However, there are certain limitations to apply the conventional NUT using the bulk wave to thin plates. In case of plates, the use of Lamb wave can be considered, however, the propagation characteristics of Lamb wave are completely different with the bulk wave, and thus the separate study for the nonlinearity of Lamb wave is required. For this work, this paper analyzed first the conditions of mode pair suitable for the practical application as well as for the cumulative propagation of quadratic harmonic frequency and summarized the result in for conditions; (1) phase matching, (2) non-zero power flux, (3) group velocity matching, and (4) non-zero out-of-plane displacement. Experimental results in aluminum plates showed that the amplitude of the secondary Lamb wave and nonlinear parameter growed up with increasing propagation distance at the mode pair satisfying the above all conditions and that the ration of nonlinear parameters measured in Al6061-T6 and Al1100-H15 was closed to the ratio of the absolute nonlinear parameters.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.12
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• pp.1427-1430
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• 2014

A thermal barrier coating (TBC) prevents heat directly transferring from a high-temperature flame to a substrate. The TBC system comprises a top coating and bond coating. TBC technology reduces the substrate surface temperature by about $100{\sim}170^{\circ}C$. In the TBC system, internal stress is generated by the difference in thermal expansion coefficients of the substrate and coating. The internal stress also differs according to the shape and position of the blade. In this study, finite element analysis was performed for different curvatures of coin-shaped specimens, which are commonly used for thermal fatigue tests, and the changes in internal stress of the TBC system were compared. Based on the results, the curvature at which the minimum stress occurs was derived, and the thermal stress was confirmed to increase with the difference between a given curvature and the curvature with the minimum stress.

• Journal of Yeungnam Medical Science
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• v.24 no.1
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• pp.55-67
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• 2007

Background : The goal of this study was to examine the health behaviors of nurses and provide basic information on health promotion for nurses. Materials and Methods : A self-administered questionnaire survey was completed by 340 nurses working at a university hospital in Daegu, Korea from March 6 to March 30, 2006. The questionnaire included demographic characteristics, working environment, health behaviors, self-assessed health status, and the practice of health promotion activities according to the work group(shift group vs. non-shift group). Results : There were significant differences in 'regular diet', 'drinking', 'ordinary health management', 'regular exercise', 'leisure activities', 'rest', and 'feeling of fatigue' between the two groups. The score for the practice of health promotion activities of the non-shift group was 121.9, which was higher than the 115.4 for the shift group. By field of practice of health promotion activities, there were significant differences in 'self-realization' and 'nutrition' between the two groups. Conclusion : The shift group did not appear to have enough time to take care of their health. It is therefore important to provide a working environment in which nurses are encouraged to increase their interest and efforts to maintain healthy behaviors. In addition, programs for education and training should be developed to help nurses adopt healthy life styles and enhance their self-esteem.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.352-364
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• 1997

This study examined and analyzed users' behavior to recreation forest facilities and their satisfaction to recreation forest in order to offer some basal data which would be helpful to create new recreation forest, to supply users' needs in exsiting recreation forest, and to make excellent maintenance of recreation forest. The results are as follows ; Restroom, campground and forest aromatic bath ground were the most popular facilities with the users of recreation forest. And restroom, snack stand and water cooler were the most required facilities by the users. Before using recreation forest, users' expectation to enjoy aesthetics of nature, to be released from their fatigue and to rest, was the highest one. And users were satisfied most as they expected most from recreation forest. The major variables played for users' satisfaction about facility allocation and its harmony to the forest, were how clean the facilities are, how well they are repaired and maintained, how much noise users make around them, how easy to use them, and how beautiful the surroundings are. Users' satisfaction variables about vegetation condition of recreation forest, were diversity of vegetation, the shade of trees, the reservation of the forest, and the accordance of vegetation with the surroundings. Users' satisfaction variables about facility condition in recreation forest, were how easy to access to the recreation facilities and restroom, how clean they are, how well the trash cans are allocated, how easy to access to the field kitchen. And how good the forest is protected and nurtured, how well the forest managers conduct users' behavior, how effectively recreation forest is guided and informed to the public, were their major satisfaction variables about the management of Recreation Forest.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.7
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• pp.970-974
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• 2012

Prunus mume is said to aid in the recovery of fatigue and improvement of liver and stomach functions. To obtain the best benefits of the whole fruit, fresh green Prunus mume was de-seeded and the fruit pulp was vacuum dried. The vacuum-dried pulp was powdered and sieved through a 250 ${\mu}m$ sieve. Then the sieved green Prunus mume powder (GPP) was granulated with water (GPPGW) and with Prunus mume extract (GPPGE) with a fluid bed coater. The physicochemical and sensory properties of GPP, GPPGW, and GPPGE were then evaluated. As a result, the water dispersibility (dispersible time) of GPP, GPPGW, and GPPGE was 21.19 sec, 6.46 sec, and 4.85 sec, respectively. The powder fluency (angle of repose) of GPP, GPPGW, and GPPGE was $11.25^{\circ}$, $8.65^{\circ}$, and $9.52^{\circ}$, respectively. The overall consumer acceptance of GPP, GPPGW, and GPPGE was 3.50, 4.62 and 5.00, respectively. Inconclusion, Prunus mume can be used as granulated whole fruit pulp with good powder fluency and dispersibility.

• Journal of Korean Academy of Nursing
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• v.29 no.4
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• pp.766-779
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• 1999

The purpose of this study was to investigate the relationship between the burden on families who live with an elderly person suffering from senile dementia, and the degree of their depression. There were 400 participants in this study, staying in the Seoul and Kyonggi areas from August 1, 1997 to February 28, 1998. Among the group, 100 participants took care of their patient at home, and another 300 participants left 100 patient at a day-care center, 100 sanatorium for senile dementia(asylum for helpless elderly people), 100 an infirmary for elderly people. Eventually 242 subjects out of the 400 were selected for the data analysis. The Zarit (1980) tool was employed to measure the degree of burden and Zung's(1965) “Self-Rating Depression Scale” was employed for the data analysis. The data was analyzed, and the percentage, t-test, ANOVA and Person's Correlation Coefficient were calculated. The results are as follows : 1. The average degree of burden that care-giving families felt was 49.13, which is somewhat high. 2. The average degree of depression that care -giving families felt was 51.95, which is relatively high. 3. The degree of burden was directly affected by the relation with the patient(F＝2.48, P＜.05), and the socio-economic status of the family(F＝5.17, P＜.05). Its also affected by the patient's educational status(F＝2.17, P＜.05). 4. The degree of depression of the family was significantly dependent on sex(t＝-2.05, P＜.05), age (F＝2.99, P＜.05), the relationship with the patient(F＝3.65, P＜.01), socio-economic status (F＝7.74, P＜.001), occupation(t＝2.82, P＜.01), health status(F＝4.42, P＜.01), and the place of residence(F＝4.30, P＜.01), The patient characteristics was significantly dependent on his/her educational status(F＝3.85, P＜.01), the period of suffering from senile dementia(F＝2.47, P＜.05), and smoking habit(F＝6.17, P＜.001). 5. The relationship between the degree of burden and that of depression reads r＝0.43, which is statistically positive correlation in the high significant level. Upon analyzing the entire summation, most care-givers for elderly patients suffering from senile dementia lack time in caring for themselves. They also experience chronic fatigue and mental discomfort caused by the isolation from society, curtailment of certain activities, a sense of responsibility for their patients, and limits of their endurance in taking care of their patients over time. In conclusion, this study emphasizes the necessity for the following propositions : 1. In order to measure the degree of burden that Korean care-giving families undergo, a new tool must be developed on the basis of Korean culture. 2. An educational program based on the demands that care-giving families undergo must be developed, and its clinical effect also has to be examined.

• Journal of Korean Society of Steel Construction
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• v.9 no.4 s.33
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• pp.489-500
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• 1997

The number of railway bridges in Korea reaches to about 3,000. Among them, the ratio of steel bridges is about 47%. Most of the long span railway bridges take the truss type, its number is 15 in Korea. These bridges have more than 30 years service life, it is expected that the damages of cracks and corrosion is going. Therefore, the estimation of fatigue life with random stress is considered as significant subject in maintenance. In this paper, the random stress was measured in bridges and counted the stress cycles using the rainflow counting method So, the stress range frequencies and their equivalent stress are obtained and the amplification factor for the span length, bridge types and traveling speed is assessed by the dynamic testing. From the results, the stress range of the stringer and the lower chord is higher than the other members and the characteristics of the stress histogram is varied to the loading system and the amount of the passing through trains. And the impact effects are depended on the traveling speed as well as the span length.

• Journal of Sasang Constitutional Medicine
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• v.10 no.1
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• pp.235-252
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• 1998

1. Background and Purpose : I intended to be helpful to understand constitutional symptoms of a disease and an application of the prescription through a clinical study of Taeumin Chongsim Yonja Tang. 2. Methods : I studied 125 patients(62 men and 63 women) treated with Taeumin Chongsim Yonja Tang in constitutional clinic of Dongguk Pundang Oriental Hospital. And then I investigated the characteristics of Chongsim Yonja Tang treated patients, remedial values and side effects. 3. Results : Taeumin Chongsim Yonja Tang was used in all age groups both men and women. There were 60 kinds of chief complaints including numbness of hands and feet, headache and fatigue etc. The distributions of remedial values were slightly improved(60.8%), much improved(15.2%), no improved(24.0%) and there was no aggravated patient. Using the prescription, mostly I prescribed only Taeumin Chongsim Yonja Tang without any changing, and added 2-3 herbs to the prescription according to the symptoms of a disease. Taeumin Chongsim Yonja Tang was affected in remedial values by the period of sufferring from illness, treatment and medication. Side effects were diarrhea, indigestion and so on.