• KCI Concrete Journal
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• v.14 no.2
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• pp.81-85
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• 2002

The strength development of concrete is influenced by temperature and cement type which greatly affect hydration degree of cement. There is not pertinent concrete strength management method in korea. There are several methods for estimating the in-place strength of concrete. One such method is the maturity concept. The maturity concept is based on the fact that concrete gains strength gradually as a result of chemical reactions between cement and water; and for a specific concrete mixture, strength at any age and at normal conditions is related to the degree of hydration. The rate of hydration and, therefore, strength development of a given concrete will be a function of its temperature. Thus, strength of concrete depends on its time-temperature history. The goals of the present study are to investigate a relationship between strength of high-strength concrete and maturity that is expressed as a function of an integral of the curing period and temperature and predict strength of concrete.

• Imaging Science in Dentistry
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• v.41 no.3
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• pp.107-113
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• 2011

Purpose : The purpose of this study was to present the clinical features of a case series of osteomas in the craniofacial region and to compare them with those described in the dental literatures. Materials and Methods : A retrospective study of 18 patients diagnosed with osteomas in the craniofacial region was performed. The age, gender, location, symptoms, and the radiological findings were recorded. Results : There were 13 women and 5 men from 18 years to 69 years of age (mean age, $42{\pm}27$ years). Fourteen osteomas were found in the mandible (78%), two in frontal sinus, one in sphenoid bone, and one in maxilla. Conclusion : Osteomas are benign tumors composed of mature compact bone or cancellous bone. They are essentially restricted to the craniofacial skeleton and rarely, if ever, are diagnosed in other bones.

• Korean Journal of Child Studies
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• v.17 no.2
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• pp.163-180
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• 1996

Employing an ethnographic approach, this case study analyzed the psychological welfare of 2 teenage and one early-twenties heads of family. The subjects were Sun-Ju (female, age 22, seamstress), Ji-Hyun (female, age 14, junior high school student), and Seung-Hwan (male, age 16, junior high school student). This study was processed between 9 March 1996 and 11 May 1996. The results show that teenage and early-twenties heads of family have ambivalent feelings, meaning two extreme psychological conditions that are not consistent. Three types of teenage-early twenties heads of family ambivalence were caused by diverse role dimensions (e.g., nursing, supporter, beneficiary, and independent subject roles). Revision of the present welfare system, particularly the protection system For teenage-early twenties heads of family was recommended. Further research is also needed to determine various factors harmful to their psychological welfare.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.149-153
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• 2015

We present an ongoing study of the complete sample of supernova remnants (SNRs) and candidates in the Magellanic Clouds. 108 objects in both Clouds are considered to be either SNR or reliable candidates. This represents the most complete sample of all known SNRs in any galaxy. It therefore allows us to study SNR population properties such as the age-diameter (Age-D) relation. Here, we show that this Age-D relation is strongly dependant on the local environment in which SNRs are residing.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1131-1138
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• 2008

Diabetic complications are a leading cause of blindness, renal failure, and nerve damage. Additionally, diabetes-accelerated atherosclerosis leads to increased risk of myocardial infarction, stroke, and limb amputation. At the present time, 4 main molecular mechanisms have been implicated in hyperglyceamia-mediated vascular damage. In particular, advanced glycation endproducts (AGE), which are formed by complex, heterogeneous, sugar-derived protein modifications, have been implicated as a major pathogenic process for diabetic complications. Recently, AGE inhibitors such as aminoguanidin, ALT-946, and pyridoxamine have been reported. Such an integrating paradigm provides a new conceptual framework for future research on diabetes complications and on discovering drugs to prevent the progression of AGE-induced maladies.

• JSTS:Journal of Semiconductor Technology and Science
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• v.2 no.2
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• pp.102-110
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• 2002

In this paper, we present the fabrication of tunable capacitors and 3-dimensional inductors. This work was related to fabricated 3-dimensional device for need of micro device in developing new intelligence age. This device was fabricated by electroplating used electroplating PR and high-vacuum evaporation of metal. Fabricated micro-inductor is consisted of air-bridge on electroplating rod and electroplated core. Micro-capacitor is consisted of thin metal membrane and electroplated core. Electroplating material is used Cu metal solvent. Air-gap between metal-layers function as almost perfect isolation layer. The most advantage of our micro-inductor and micro-capacitor compared to present device is a possibility that can fabricate on RF MEMS(microelectro-mechanical systems) application with high performance and various function. In this paper, we present the fabrication of tunable capacitors and 3-dimensional inductors. This work was related to fabricated 3-dimensional device for need of micro-device in developing new intelligence age. This device was fabricated by electroplating used electroplating PR and high-vacuum evaporation of metal. Fabricated micro-inductor is consisted of air-bridge on electroplating rod and electroplated core. Micro-capacitor is consisted of thin metal membrane and electroplated core. Electroplating material is used Cu metal solvent. Air-gap between metal-layers function as almost perfect isolation layer. The most advantage of our micro-inductor and micro-capacitor compared to present device is a possibility that can fabricate on RF MEMS application with high performance and various functions.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.12
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• pp.1689-1694
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• 2004

This study was conducted to develop a novel adjustment factors for 305 days using 138,103 lactation records and 1,770,764 daily records, which were based on environmental circumstances such as herd year, season, age at calving, dry period and lactating stages. The present study showed that the change of persistency of cows at the first parity from total lactacting characteristics was slowly processed, while it was rapidly changed in cows at the second parity stage. Particularly, there was an outstanding difference between the first and second parity cows. Milk yield and composition increased as the age at calving was increased. In addition, milk yield and composition were higher at the first parity on fall compared with others, and those were higher at the more than second parity on fall and winter compared with other parity stages and seasons. The cow of dry group was included into lactating records of more than second parity stage. The data indicated that optimal results arose from 45-70 days of dry period. Milk yield was decreased when dry period was longer or shorter than 45-70 days. The lactating days were divided into 17, 28 and 38 stages to compare the multiplicative correction factors. The factor was effective at 28 stages on the first parity. The total correlation coefficients were 0.93832, 0.95058 and 0.95076 at the present correction factor, 17 stage and 28 stage, respectively. At second parity, the factor was higher in dry group 1 and 3 at 17 stage, and it was higher in dry group 2 at 28 stage compared with others. Therefore, the present study showed that the percent squared bias (PSB), which was calculated from the novel correction factor, was better than previously used correction factors. Also, the present study indicated that the bias of the novel correction factor was improved, and this factor could be more accurate compared with others.

• Journal of Oral Medicine and Pain
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• v.38 no.3
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• pp.235-246
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• 2013

Age estimations by forensic odontology play a great role in personal identification. The purpose of this study was to analyze the characteristics of age estimation cases in Korea. Surveying clients who requested age estimation at the Department of Oral Medicine, Kyungpook National University Dental Hospital from March 2012 to March 2013. The results were as follows: 1. On gender distribution, females(57.14%) were more than males(42.86%). The elderly with 50's and over 60's were majorities(89.28%) of clients, and no clients were below 40's. Most of clients were equal to and lower than elementary school graduate(69.64%). 2. The most frequent reason for age discrepancy between registered age and alleged age was mistakes by family or relatives(80.36%). The purposes of age estimation were welfare(62.50%), social relationship problem(12.50%), to find right age(10.71%), and occupation(8.93%). 3. In order of route to visit at Department of Oral Medicine, they were via government office(48.21%), acquaintances(21.43%), mass media(14.29%), and clinic(10.71%). Clients had high degree of comprehension on age estimation with forensic odontology (scored 7.03 out of 10). The 2/3 of clients were satisfied with present fee for age estimation. 4. The percentage on the proximity of estimated age to alleged age was 69.81%. 4(11.43%) clients were approved on age correction by court.

• Korean Journal of Poultry Science
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• v.22 no.2
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• pp.67-75
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• 1995

The present study was conducted to estimate production performances, heritabilities, and genetic and phenotypic correlations on several economic traits in Korean native chicken. Data analyzed were the records of 1,096 pullets produced from 180 dams and 26 sires of Korean native chicken from April 19,1994 to February 26, 1995. Results obtained are surnmarized as follows: 1. The body weights(X${\pm}$SD) at 2, 8, 14 and 20 weeks of age were 114${\pm}$13, 690${\pm}$114, 1,163${\pm}$238, and 1,687${\pm}$349g, respectively. The age at first egg was 165.95${\pm}$14.54 days, and the number of eggs produced by 300 days of age were 70.78i23.47. The egg weights of the first egg and at 300 days of age were 37.88${\pm}$3.73 and 50.97${\pm}$3.69 g, respectively. 2. The heritability estimates of body weight based on the variance of sires, dams and combined components were 0.149, 0.298, and 0.224 at 8 weeks of age: 0.162, 0.220, and 0.192 at 20 weeks of age, respectively. 3. The heritability estimates of egg production traits based on the variance of sires, dams, and combined components were 0.232, 0.504, and 0.368 for age at first egg; 0.113, 0.172, and 0.143 for number of egg production by 300 days of age: 0.174, 0.352, and 0.236 for egg weight at 300 days of age, respectively. 4. The genetic correlation coefficients of some economic traits were as follows: between body weight and age at first egg, -0.354~-0.048; between body weight and number of egg production, -0.279~ -0.002; between body weight and egg weight, 0.338~0.977; between age at first egg and number of egg production, -0.791; between age at first egg and egg weight, 0.009~0.178; between number of egg production and egg weight, -0.572~ -0.256, respectively. 5. The phenotypic correlation coefficients of some economic traits were as follows: between body weight and age at first egg, -0.179~-0.006 between body weight and number of egg production, -0.045~0.074: between body weight and egg weight, 0.229~0.404: between age at first egg and number of egg production, -0.588: between age at first egg and egg weight, -0.029~0.597: between number of egg production and egg weight, -0.376~0. 019, respectively.

• Journal of Korean society of Dental Hygiene
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• v.19 no.5
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• pp.689-698
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• 2019

Objectives: The study aimed to investigate the relationship between depression and number of present teeth in Korean elderly individuals. Methods: Data for this cross-sectional survey was obtained from the records of the sixth Korea National Health and Nutrition Examination Survey (KNHANES). The subjects were 1,199 Korean elderly individuals above 65 years of age. The survey and examination data were used for the independent variables. The KNHANES included health status, nutrition survey, and oral examination. $x^2-test$ was performed to identify the characteristics of depression and number of teeth present according to the characteristics of the study subjects. Logistic regression analysis was also performed to identify the relationship between depression and number of teeth present. The statistical significance level wa sset at 0.05. Results: The prevalence of depression in the subjects was 14.8%. There were statistically significant differences in the prevalence of depression, depending on gender (p<0.001), education level (p=0.001), income (p=0.001), spouse status (p<0.001), and alcohol consumption (p=0.020). The association between depression and the number of teeth present showed statistically significant difference after adjustment (p=0.040). Conclusions: Depression in elderly individuals was closely related to the number of teeth present. Therefore, public health policies for improving oral health should be established to prevent depression.