• Magazine of the Korean Society of Agricultural Engineers
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• v.15 no.2
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• pp.3018-3030
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• 1973

This study was carried out to investigate the effects of various mix designs of concrete on the compressive strengths and corrosive rates when the concretes were immersed in sea water of the West Sea, as the part of study related to durated to durability of concrete by action of the sea water. Concrete mix designs used in this study were ordinary Concrete mix, Concrete mixes with different admixtures such as fly ash, pozzolith and vinsol resin, and pozzolan concrete mix. The concrete specimens were made and cured for 7 days and 28 days in the fresh water in accordance with the Korean Standard specification for concrete. Compressive strengths of the specimens were measured after immersing the specimens for one year in fresh water and sea water which were placed indoors. The sea water used in this test was taken from the Bay of Ahsan. Corrosive rate was also tested after immersing the specimens in the same sea water and placed indoors for one year. The results obtained from the tests are summarized as follows; 1. Compressive strength of an ordinary concrete was the lowest of the various mix desings of concrete immersed both in the fresh water and the sea water. Therefore, the uses of pozzolan cement, fly ash, pozoolith and vinsol resin in mix design of concrete had and effect on increasing compressive strength. 2. Pozzolan concrete was the most effective on compressive strength in the fresh water, but it had less effect than concrete with fly ash admixture immersed in the sea water. 3. The use of fly ash admixture in mix design of concrete showed higher strength as the immersing age is longer both in fresh water and sea water than the other concretes besides pozzolan concrete, but the concretewith fly ash admixture had lower strength than pozzolan concrete in the sea water. Therefore, concrete with fly ash admixture might be better than the pozzolan concrete as far as durability of concrete to sea water was concerned. 4. The use of pozzolith admixture in mix design of concrete had less compressive strength than the use of pozzolan cement for fly ash admixture both in fresh water and sea water. However, the concrete with pozzolith admixture was much stronger than one with vinsol resin admixture in fresh water, but somewhat stronger in the sea water. 5. Though the use of vinsol resin admixture was more effective than ordinary concrete on compressive strength both in fresh water and sea water, it was the least compressive strength among the other concretes. 6. Relation between compressive strengths and absorption rates of every kind of concrete besides concrete with fly ash admixture showed a linear regression line and the compressive strength is highee as the absorption rate is lower. Concrete with fly ash admixture had extremely high strength in comparison with corresponding adsorption rates of the other concretes. 7. Corrosive appearance on the surface of concretes was not occured significantly when exposed to the sea water for one year, However, the specimens of concretes besides ordinary concrete were a little heavier than those cured in fresh water for 28 days.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.2
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• pp.176-182
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• 2017

This study was conducted to evaluate the protein requirement for maintenance of fattening Korean black goat (Capra hircus coreanae). Six male goats with average initial body weight (BW) of $31.78{\pm}4.54kg$ and an average age of 8 months were used in this study. The experiment had a replicated duplicated $3{\times}3$ Latin square design for balancing carryover effects. In the course of the experiment, each of Black goats were fed three diets that were formulated to contain T1 (13%), T2 (16%) and T3 (19%) levels of crude protein (CP). A 14-day diet adjustment period was followed by a 5-day collection period. Dry matter intake (DMI) of groups fed diets with T2 was 966.67g/d which was higher than group fed diets with T1 and T3 were 925.14g/d and 936.08g/d each. Average daily gains (ADG) of black goats were the highest in T2(167.13g/d) But, there was no significant difference. Dietary protein levels affected the apparent digestibility of CP (p<0.05). A significant difference was found in CP intake among treatments and goats receiving T3, T2, and T1 recorded 181.23, 154.57, and 128.78g CP/d, respectively. This was excepted because CP intake is proportional to CP content of diet, which from highest to lowest was as follows: T3 (19%) > T2 (16%) > T1 (13%). Intercept of the regression equation between CP intake and CP balance indicated that maintenance CP requirement was 1.63g/BW0.75.

• Journal of Nutrition and Health
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• v.41 no.8
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• pp.733-741
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• 2008

In the present study, we comprehensively examined the associations of plasma levels of total adiponectin and high molecular weight (HMW) adiponectin with the features of cardiometabolic risks including body fat distribution, dyslipidemia, insulin resistance and inflammatory markers in a cross-sectional study of 110 treated hypertensive patients. Blood lipid profiles, high sensitivity C-reactive protein (hsCRP) and homeostasis model assessment of insulin resistance (HOMA- IR) derived from fasting glucose and insulin concentrations were determined. Plasma levels of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-6 (IL-6) and intercellular adhesion molecule-1 (ICAM-1) were analyzed using ELISA. The results showed that plasma levels of HMW-adiponectin were negatively associated with body mass index (BMI, r = - 0.203, p < 0.05) and waist circumference (r = -0.307, p < 0.01), which was not shown in total adiponectin. Plasma levels of HMW-adiponectin were negatively associated with triglyceride (r = -0.223, p < 0.05) and positively associated with HDL-cholesterol (r = 0.228, p < 0.05). Plasma levels of adiponectin were positively associated with HDL-cholesterol (r = 0.224, p < 0.05). Plasma levels of HMW-adiponectin were negatively associated with hsCRP (r = -0.276, p < 0.01) and IL-6 (r = -0.272, p < 0.01). In addition, there were weak associations between plasma levels of HMWadiponectin and TNF-${\alpha}$ (r = -0.163, p = 0.07) and ICAM-1 (r = -0.158, p = 0.09). However, there were no significant associations of total adiponectin with inflammatory markers except hsCRP (r = -0.203, p < 0.05). Stepwise multiple linear regression analysis showed that only plasma levels of HMW-adiponectin was an independent factor influencing serum levels of hsCRP, a marker of systemic low grade inflammation, after adjusting for age, gender, BMI, waist circumference, alcohol intake, smoking status, blood lipids, total adiponectin and drug use (p < 0.01). These results suggest that HMW-adiponectin, rather than total adiponectin, is likely to be closely associated with the features of cardiometabolic risks in treated hypertensive patients and might be effective biomarker for the prediction of cardiovascular disease.

• Journal of Nutrition and Health
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• v.41 no.8
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• pp.754-766
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• 2008

This study was performed to evaluate the effect of nutrient intake levels on the relative risk of breast cancer in the Daegu and Gyeongbuk area. The case subjects were 103 patients newly diagnosed as breast cancer at Kyungpook National University Hospital. The control subjects were 159 healthy women without breast cancer-related disease in the same community selected by frequency matching of age and menopausal status. The survey was administered by individual interviews by trained dietitians using semiquantitative food frequency questionnaires. The odds ratios were determined by using unconditional logistic regression after adjusting for the confounding factors found in the analysis of general characteristics of the subjects. In overall, it has been found that high consumptions of energy and carbohydrates significantly raised the relative risk of breast cancer, and that high intakes of total fat, plant fat, dietary fiber, all kinds of fatty acids, vitamin E and calcium significantly lowered the risk of breast cancer. The results of the study suggest that the possible protective factors to the breast cancer risk include a higher intakes of total fat, especially plant fat, dietary fiber, and micronutrients such as vitamin E, folic acid, calcium, phosphorus and potassium. On the other hand, high intakes of energy and carbohydrate appeared to be the risk factors.

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.82-90
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• 2010

The ecological characteristics of the Korean Aucha perch, Coreoperca herzi, were determined in order to estimate stock of the mid-upper system of the Seomjin River. The age was determined by counting the otolith annuli. The oldest fish observed in this study was 5 years old. Relationships between body length (BL) and body weight (BW) were $BW=0.0195BL^{3.08}$ ($R^2=0.966$) (p<0.01). Relationships between the otolith radius (R) and body length (BL) were BL=3.882R+1.66 ($R^2=0.944$). The von Bertalanffy growth parameters estimated from a non-linear regression method were $L_{\infty}=19.68\;cm$, $W_{\infty}=188.64\;g$, $K=0.17\;year^{-1}$ and $t_0=-1.46$ year. Therefore, growth in length of the fish was expressed by the von Bertalanffy's growth equation as $L_t=19.68$ ($1-e^{-0.17(t+1.46)}$) ($R^2=0.997$). The annual survival rate (S) was estimated to be $0.666\;year^{-1}$. The instantaneous coefficient of natural mortality (M) of estimated from the Zhang and Megrey method was $0.346\;year^{-1}$, and instantaneous coefficient of fishing mortality (F) was calculated $0.061\;year^{-1}$. From the estimates of survival rate (S), the instantaneous coefficient of total mortality(Z) was estimated to be $0.407\;year^{-1}$.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.2
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• pp.370-376
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• 2005

In children, dental anxiety of dental treatment has been recognized as a source of problems in patient man agement for many years. Dental anxiety can be causes of negative cooperation, cancel and avoid of dental treatment. Therefore, dentist and dental team should recognize of child's dental anxiety as early as possible and manage appropriately. In previous studies, it is reported that parental dental anxiety affect dental anxiety and cooperation of their child. And it is parental decision which results in a child's visit to the dentist, rather than a child's decision in most cases. Therefore, it is important to identify the relationship of dental anxiety between child and parent. We estimated child's dental anxiety before dental treatment using Venham Picture Scale that is useful even a very young child and parental dental anxiety using Corah's dental anxiety scale. Then, two values above were compared. Child's cooperation, temperament, sex, age, parental education were estimated and compared with dental anxiety, too. The results were as follows: 1. There are positive relationship of dental anxiety between child and parent with the correlation analysis(P<0.02). 2. There are negative relationship of child's dental anxiety and child's cooperation with the correlation and regression analysis(P<0.001). 3. Low anxiety group has lower mean value of four temperament item with the Student's t-test. But, there is no statistical differences(P>0.1). 4. Girl and younger group have higher mean value of dental anxiety than boy and older group with the Student's t-test(P<0.001). 5. Low educated parents have higher mean value of dental anxiety than high educated parents with the Student's t-test(P>0.1).

• Sleep Medicine and Psychophysiology
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• v.27 no.1
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• pp.16-23
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• 2020

Objectives: Sleep disturbance in the elderly is associated with cognitive decline. Sleep quality is known to deteriorate with age, and prospective studies seldom have examined the relationship between sleep quality and cognitive function. This study investigates the relationship between early sleep quality and cognitive function based on six-year follow-up data of community individuals older than 60 years. Methods: The participants included 622 community elderly people older than 60 years from Jinju-Si. The final analysis comprised 322 elderly people. Pittsburgh sleep quality index (PSQI) and the Korean version of Consortium to Establish a Registry for Alzheimer's Disease (CERAD-K) were used to assess early sleep quality and cognitive function after six years. Multiple linear regression analysis was performed to investigate the association between early sleep quality and cognitive function in the elderly. Results: Early sleep quality (PSQI) was significantly associated with the results of the digit span test, clock drawing test (clox 1), and word recall test after six years. Sleep quality (PSQI) decreased significantly after six years, and lower quality of sleep (PSQI) score was associated with higher digit span test score (β = -0.167, p = 0.026) and higher clock drawing test score (β = -0.157, p = 0.031). Lower quality of sleep (PSQI) score was associated with higher word recall test (β = -0.140, p = 0.039). Conclusion: The digit span test, word recall test, and clock drawing task (CLOX 1) shown to be significantly associated to sleep quality can be performed fast and easily in clinical practice. It is important to assess early cognitive function in the elderly with poor sleep quality, and further studies could suggest that these tests may be useful screening tests for early dementia in elderly with poor sleep quality.

• Tuberculosis and Respiratory Diseases
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• v.64 no.6
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• pp.414-421
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• 2008

Background: Recently, in addition to multi-drug resistant tuberculosis (MDR-TB), extensively drug-resistant tuberculosis (XDR-TB) has become rapidly growing public health threat. This study examined the clinical differences between pulmonary TB patients with extensively drug resistance (XDR) and multi-drug resistance (MDR) at the National Medical Center in Korea in order to determine the clinical characteristics associated more with XDR-TB than MDR-TB. Methods: Patients who received a diagnosis of culture-confirmed pulmonary TB and a drug sensitivity test (DST) for anti-TB drugs at the National Medical Center between January 2000 and August 2007 were enrolled in this study. The patients were identified into the XDR-TB or MDR-TB group according to the DST results. The clinical characteristics were reviewed retrospectively from the medical records. Statistical analysis for the comparisons was performed using a ${\chi}^2$-test, independent samples t-test or binary logistic regression where appropriate. Results: A total 314 patients with culture-confirmed pulmonary TB were included. Among them, 18 patients (5.7%) had XDR-TB and 69 patients (22%) had MDR-TB excluding XDR-TB. A comparison of the clinical characteristics, revealed the XDR-TB group to have a higher frequency of a prior pulmonary resection for the treatment of TB (odds ratio [OR], 3.974; 95% confidence interval [CI], 1.052~15.011; P value 0.032) and longer average previous treatment duration with anti-TB drugs, including a treatment interruption period prior to the diagnosis of XDR, than the MDR-TB group (XDR-TB group, 72.67 months; MDR-TB group, 13.09 months; average treatment duration difference between two groups, 59.582 months; 95% CI, 31.743~87.420; P value, 0.000). In addition, a longer previous treatment duration with anti-TB drugs was significantly associated with XDR-TB (OR, 1.076; 95% CI, 1.038~1.117; P value, 0.000). A comparison of the other clinical characteristics revealed the XDR-TB group to have a higher frequency of male gender, diabetes mellitus (DM), age under 45, treatment interruption history, cavitations on simple chest radiograph and positive result of sputum AFB staining at the time of diagnosis of XDR. However, the association was not statistically significant. Conclusion: Pulmonary TB patients with XDR have a higher frequency of a prior pulmonary resection and longer previous treatment duration with anti-TB drugs than those with MDR. In addition, a longer previous treatment duration with anti-TB drugs is significantly associated with XDR-TB.

• Journal of dental hygiene science
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• v.9 no.5
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• pp.497-506
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• 2009

This study was conducted to estimate the dental caries experience, oral hygiene status and the factors influencing the dental disease in the smoking adolescents and to provide the baseline data for managing smokers efficiently. We recruited 156 smokers(male: 106, female: 50) in middle, high school students in 5 day Non-smoking program in seoul city and 176 non-smokers(male: 64, female: 112) by matching method for considering sex and age from June 1 to August 31 2009. Data on general characteristics, basic oral health care, smoking factors, self-efficiency, control of oral health, oral health promotion behavior, knowledge of oral health were collected by a questionnaire interview. DMFT index, DT index, MT index, FT index, Plaque index, Calculus index were calculated by the oral examination. The results of this study were as follows. 1. Dental clinic visit(p < 0.05), self-perception of oral health status(p < 0.001), oral health concern (p < 0.01) in non-smoker group were significantly higher than that of smoker group. 2. self-efficiency(p<0.05), oral health promotion behavior(p < 0.05) in non-smoker group were significantly higher than that of smoker group. 3. DT index, Plaque index, Calculus index in non-smoker group was significantly lower than that of smoker group(p < 0.0001). 4. The fewer smoke amount, the lower DT index(p < 0.05), Plaque index(p < 0.01), Calculus index(p < 0.001). 5. It was significant correlated among DT index and self-efficiency, oral health promotion behavior, control of oral health. 6. In multiple regression analysis, oral health promotion behavior, Plaque index was proved as a significant factors related with the degree of dental caries experience in smoking adolescents. In other word, the higher oral health promotion behavior, the lower Plaque index, the fewer DT index.

• Management & Information Systems Review
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• v.33 no.1
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• pp.191-217
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• 2014

The Purpose of this study is to find the effect factors of R&D investment in SMEs which plays an important role in the national economy, and the differences of the effect factors by the type of SMEs. The subject of this study is about 3,400 SMEs mentioned in "The survey of technical statistics on SMEs in 2007" by Korea Federation of Small and Medium Business. The effect factors are related with the size of business, the infrastructure of R&D and the activities of R&D which have been studied by many researchers. The methods of analysis are regression analysis, moderating effect analysis and the software package used is SPSS 12.0. The results of the study are as fallow. First, it was found that unlike in previous studies which show the effect of the elements of business's size, research infrastructure, research activities on R&D investment, one element alone can't be considered for meaningful result but the various elements have effect on R&D investment at the same time. In other words, the number of employees and the sales as the elements of business's size, the ratio of researchers, the technical ability, the ratio of equipment possession and the intellectual properties as the elements of R&D infrastructure, the activity of ideas and joint research as the elements of R&D activities have positive(+) effect, whereas the participation of CEO in the activity of R&D as the elements of R&D activities activity has negative(-) one. The number of employees, the ratio of researchers, and the sales had relatively high influence whereas equipment possession, technical ability, intellectual properties, the participation of CEO in the research, the activity of idea, joint research had relatively low influence. Next, it was also found that there are differences of the effect factors over the types of SMEs. SMEs were classified into 19 types by eight criteria such as start-ups and existing business by business age; small business and medium business by size; manufacturing business and service business by product type;independent business and subcontractor business by dealing type; businesses in the entering, growing, maturing and restructuring stage by growth stage; businesses with low, medium and high technology by technological level; pioneering business and non-pioneering business by industrial type; and businesses with state-of-the-art technology and non-advanced business by the level of business activities. The meaning of this study lies in the fact that it found the various effect factors should be considered at the same time when conducting study on SMEs' R&D investment, and the differences by the type should be acknowledged. This study surpassed the limitations of the previous studies which focused on a couple of factors and types. This study result can also be considered for other studies on achievement, organization, marketing and others. Moreover, it shows that a differential policy by business type is needed when formulating SME policy.