• Steel and Composite Structures
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• v.51 no.2
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• pp.103-116
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• 2024

Based on the consistent couple stress theory (CCST), we develop a unified formulation for analyzing the static bending and free vibration behaviors of functionally graded (FG) microscale beams (MBs). The strong forms of the CCST-based Euler-Bernoulli, Timoshenko, and Reddy beam theories, as well as the CCST-based sinusoidal, exponential, and hyperbolic shear deformation beam theories, can be obtained by assigning some specific shape functions of the shear deformations varying through the thickness direction of the FGMBs in the unified formulation. The above theories are thus included as special cases of the unified CCST. A comparative study between the results obtained using a variety of CCST-based beam theories and those obtained using their modified couple stress theory-based counterparts is carried out. The impacts of some essential factors on the deformation, stress, and natural frequency parameters of the FGMBs are examined, including the material length-scale parameter, the aspect ratio, and the material-property gradient index.

• Korean Journal of Community Nutrition
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• v.10 no.5
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• pp.677-692
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• 2005

The assessment of sodium intake is complex because of the variety and nature of dietary sodium. This study intended to develop a dish frequency questionnaire (DFQ) for estimating the habitual sodium intake and a short DFQ for screening subjects with high or low sodium intake. For DFQ112, one hundred and twelve dish items were selected based on the information of sodium content of the one serving size and consumption frequency. Frequency of consumption was determined through nine categories ranging from more than 3 times a day to almost never to indicate how often the specified amount of each food item was consumed during the past 6 months. One hundred seventy one adults (male: 78, female: 93) who visited hypertension or health examination clinic participated in the validation study. DFQ55 was developed from DFQ112 by omitting the food items not frequently consumed, selecting the dish items that showed higher sodium content per one portion size and higher consumption frequency. To develop a short DFQs for classifying subjects with low or high sodium intakes, the weighed score according to the sodium content of one protion size was given to each dish item of DFQ25 or DFQ14 and multiplied with the consumption frequency score. A sum index of all the dish items was formed and called sodium index (Na index). For validation study the DFQ112, 2-day diet record and one 24-hour urine collection were analyzed to estimate sodium intakes. The sodium intakes estimated with DFQ112 and 24-h urine analysis showed $65\%$ agreement to be classified into the same quartile and showed significant correlation (r=0.563 p<0.05). However, the actual amount of sodium intake estimated with DFQ112 (male: 6221.9mg, female: 6127.6mg) showed substantial difference with that of 24-h urine analysis (male: 4556.9mg, female: 5107.4mg). The sodium intake estimated with DFQ55 (male: 4848.5mg, female: 4884.3mg) showed small difference from that estimated with 24-h urine analysis, higher proportion to be classfied into the same quartile and higher correlation with the sodium intakes estimated with 24-h urine analysis and systolic blood pressure. It seems DFQ55 can be used as a tool for quantitative estimation of sodium intake. Na index25 or Na index14 showed $39\~50\%$ agreement to be classified into the same quartile, substantial correlations with the sodium intake estimated with DFQ55 and significant correlations with the sodium intake estimated with 24-h urine analysis. When point 119 for Na index25 was used as a criterion of low sodium intake, sensitivity, specificity and positive predictive value was $62.5\%,\;81.8\%\;and\;53.2\%$, respectively. When point 102 for Na index14 was used as a criterion of high sodium intake, sensitivity, specificity and positive predictive value were $73.8\%,\;84.0\%,\;62.0\%$, respectively. It seems the short DFQs using Na index 14 or Na index25 are simple, easy and proper instruments to classify the low or high sodium intake group.

• Korean Journal of Environment and Ecology
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• v.28 no.3
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• pp.302-313
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• 2014

This study was conducted to compare the characteristics of fish distribution according to sand type stream and cobble type stream the 4 stream selected every season. The collected Korea endemic species during the survey period were 24, including Acheilognathus gracilis. Dominant species of Hongcheon stream and Muju Namdae stream was Zacco koreanus, each accounting for 39.9% and 28.4% in order, and dominant species in Yanghwa stream was Rhodeus notatus, 13.6%, and those in Gap stream was Z. platypus, by 26.0%. As a result of community analysis, dominant index was 0.27~0.63, diversity index was 1.92~2.67, evenness index was 0.6~0.79, richness index was 3.09~3.53, and dominant index was the highest in Hongcheon stream, and the indices of diversity, evenness and richness were the highest in Yanghwa stream. As a result of tolerance guild analysis, Hongcheon stream and Muju Namdae stream with a variety of substrates accounted for relatively higher rate by 50.1% and 46.4% in sensitive species respectively, and Yanghwa stream and Gap stream with greater sand substrates had 0.5% and 5.3% scarce rate of sensitive species. As a result of similarity analysis using the species, population and substrate structures of the fisheries appeared in each stream, cobble type streams such as Hongcheon stream and Muju Namdae stream were the most similar by 50.4% in species and population, 95.2% in bed structure. As a result of IBI analysis, Hongcheon stream and Muju Namdae stream appeared as 'Class A,' Yanhwa stream and Gap stream as 'Class B' and the two groups of cobble type stream and sand type stream were divided as a result of principal components analysis.

• The korean journal of orthodontics
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• v.26 no.4
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• pp.349-358
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• 1996

To extract or not to extract permanent teeth for the correction of malocclusion has been a great debate in the history of orthodontics, and there is a variety of analytic methods and criteria to aid in the diagnosis. Extraction formulas that has been presented are many analytic methods that depend on arch length discrepancy, dental prominence, and skeletal pattern of the each patients. Of these analysis, the most important diagnostic factor is patient's skeletal pattern. Because the behavior of the dentition is closely dependent upon the skeletal pattern of each patient, dentition must be arranged within that person's skeletal frame. EI(Extraction Index) is composed of CF, interincisal angle, and lip position. CF is made of ODI and APDI that differentiate vertical and horizontal component of the skeletal pattern. So, EI not only represents patient's skeletal pattern, but also takes facial appearance into consideration. This study was undertaken to investigate EI and related cephalometric variables on the cephalogram of Korean adolescents which consisted of 153 persons with normal occlusion, harmonious skeleton and pleasing face. The following conclusions were obtained. 1. The mean value of the ODI is $73.5^{\circ}$, APDI $82.5^{\circ}$, CF $156.3^{\circ}$ 2. The mean value of the interincisal angle is $123.6^{\circ}$ 3. The mean distance of upper lip to E-line is 0.0mm, lower lip to E-line is 1.4mm. 4. The mean value of the EI is $153.8^{\circ}$.

• Korean Journal of Community Nutrition
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• v.25 no.5
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• pp.406-415
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• 2020

Objectives: The aim of this study was to compare the nutritional intake and Diet Quality Index-International (DQI-I) of gynecological cancer survivors and normal women. Methods: This study compared the anthropometric indices, dietary behavior, nutritional intake, and DQI-I in women with previous history of breast or uterine cancer [Gynecological cancer survivors group (GCSG, n=126)] and normal women [Normal control group (NCG, n=7,011)] using the 2013~2016 Korea National Health and Nutrition Examination Survey data. Results: Body mass index and waist circumference were lower in the GCSG compared the NCG. The frequency of skipping breakfast and eating out was higher in the NCG compared to GCSG. Energy and fat intake were significantly higher in the NCG than in the GCSG, whereas intake of all minerals and vitamins (excluding thiamine), and dietary fiber intake were higher in GCSG. It was observed that the fatty acid intake of the GCSG was significantly lower than that of the NCG. The diet quality evaluation using DQI-I results showed that GCSG was higher in the "within-group" diet variety and adequacy of vegetable group than the NCG, whereas the intake level of the fruit group was higher in NCG. Besides, protein, calcium, and vitamin C intake were higher in the GCSG than in the NCG. The GCSG showed higher levels of total fat and saturated fat moderation than the NCG, whereas cholesterol moderation showed the opposite results. The results of DQI-I comparison according to the cancer survival years showed that the overall score and scores related to diet adequacy and balance were higher in the below 5-year group, whereas the over 5-year group scored higher in terms of moderation of diet. Conclusions: The results of this study suggest that a chronic disease based management approach is needed in cancer survivors. The study provides important data which can help in the preparation of guidelines for long-term lifestyle and diet management, in these patients.

• Korean Journal of Agricultural Science
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• v.6 no.1
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• pp.1-14
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• 1979

Selection index methods were applied to selecting better performing rice varieties with better plant characters from rice yielding trials tested under six different cultural methods. The results obtained were summarized as follows: 1. Varieties such as NO. 3, 4, 5 and 6 were selected as best performing varieties with good plant and grain characters. 2. Selection index I computed from Hazel's method was appeared effective for selecting rice varieties grown under general optimum environmental conditions, while selection index II computed from Pesek and Baker's desired genetic gain were effective for selecting rice varieties grown under rather stressed conditions. 3. The rank of mean yield of each variety was not completely in agreement with that of index values, which indicates the importance of other characters besides yield in selecting varieties. 4. Most characters studied were high in broad sense of heritabilities. 5. No significant interaction was found between varieties and cultural methods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.72-78
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• 2016

This study examined the oral health-related quality of life of the elderly using the oral health index and dental prosthesis status, and explored methods to improve the oral health status. The data collected from 'The fifth Korean national health and nutrition examination survey 2010' were analyzed. The subjects were 2273 elderly people, aged 65 years or older, who had completed an oral examination, health questionnaires and nutrition examination. Statistical analysis was done using the SPSS 22.0 for Windows. Frequency analysis, multiple regression analysis and structural equation model were used for statistical analysis. The general characteristics, oral health index and dental prosthesis showed differences in the subjective oral health status associated with as age, ST, FS-T, T-Health, maxillary crown needs, maxillary denture needs, mandibular denture needs, chewing status associated with the income level, FS-T, maxillary crown needs, maxillary denture needs, mandibular denture needs, speaking status associated with the ST, T-Health, maxillary implant status, and maxillary denture needs. In conclusion, both the oral health index and dental prosthesis needs affect the oral health related quality of life of the elderly. Governments should implement a variety of oral health programs and dental prosthesis policies to improve the quality of life related oral health of the elderly.

• Journal of the Korean association of regional geographers
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• v.3 no.1
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• pp.35-50
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• 1997

The purpose of this research seeks to analyze the spatial variations in the sex age structure which have been shown to exist within the study atrea, the Kyonggi province in Korea. In this study it is desired to use the Age Structure Index developed by Coulson in order to describe thi sex age structure of each of 186 tracts that comprise the tracted portion of the Kyonggi province. The mechanics of computing the Age Structure Index are found in the equation describing a linear least squares trend line: y=a+bx. For each census tract, the percentage of the population in each age group(y) was plotted against the middle age of each age group(x). The a is a constant representing the value of y, when x equals zero. The b is the regression coefficient and is a measure of the angle of the slope of the least squares trend line. Thus the value of b is the Age Structure Index for each census tract. The major results of this investigation can be summarized as follows: The spatial distributions of sex age structures in the Kyonggi province are far from random. They have exhibited great regularity with the yonger sex age structures near Seoul and a sharp decline to the older sex age structures out in all derections towards rural region. The results of this investigation should have important general significance for the study of the Kyonggi province Age Structure Index is a flexible, operational definition shich allows sex age structure to be measured, mapped, and incorporated in a wide variety of methods of statistical analysis. Futurer, it has been demonstrated that sex age structure varies spatially within Seoul metropolitan finge and that this variation is relagfed to many other attributes of the population. Especially, Age Structure Index is strongly related to the variables-rate of population growth rate. density, rate of numbers of manufacturing, land price. At the same time, considerably more research is needed before a genmeral body of knowlege concerning sex age structure can be developed.

• Journal of Korea Entertainment Industry Association
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• v.15 no.6
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• pp.71-80
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• 2021

This study is aimed at analyzing the characteristics of each service quality and the requirements of the customers followed by the classification of service quality factors of youth sports clubs by using Kano model. For this purpose, a survey was conducted by targeting on 257 subjects in 10 youth sports clubs in Seoul and Gyeonggi areas and for data processing, Microsoft Office Excel 2016 and SPSS 22.0 were used to carry out Frequency Analysis, Factor Analysis, Reliability Analysis, Kano model Quality Classification, Timko's Customer Satisfaction Coefficient, and the computation and analysis of Public-service Customer Satisfaction Index. The following shows the research findings. First, as a result of using Kano model to classify each item of the service quality factors of the youth sports club through Dualistic Quality Theory Attribution, one-dimensional quality elements resulted in all 22 items of service quality factors of youth sports club. Second, the customer satisfaction coefficient computation result showed that satisfaction coefficient appeared by the order of 'kind response of the instructor,'(0.81), 'attitude of the instructor'(0.80), 'systematic lecture program'(0.76), and 'variety of program)'(0.76) and dissatisfaction coefficient appeared by the order of 'clean and pleasant facility'(-0.79), 'attitude of the instructor'(-0.76), 'kind response of the instructor'(-0.76), 'convenience of parking facility'(-0.73), and 'promptness of business process'(-0.73). Third, the public-service customer satisfaction index placing appeared by the order of the 'attitude of the instructor', 'kind response of the instructor', 'clean and pleasant facility' and 'systematic lecture program'.

• The Transactions of the Korea Information Processing Society
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• v.13 no.5
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• pp.209-216
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• 2024

Real estate market prices are determined by various factors, including macroeconomic variables, as well as the influence of a variety of unstructured text data such as news articles and social media. News articles are a crucial factor in predicting real estate transaction prices as they reflect the economic sentiment of the public. This study utilizes sentiment analysis on news articles to generate a News Sentiment Index score, which is then seamlessly integrated into a real estate price prediction model. To calculate the sentiment index, the content of the articles is first summarized. Then, using AI, the summaries are categorized into positive, negative, and neutral sentiments, and a total score is calculated. This score is then applied to the real estate price prediction model. The models used for real estate price prediction include the Multi-head attention LSTM model and the Vector Auto Regression model. The LSTM prediction model, without applying the News Sentiment Index (NSI), showed Root Mean Square Error (RMSE) values of 0.60, 0.872, and 1.117 for the 1-month, 2-month, and 3-month forecasts, respectively. With the NSI applied, the RMSE values were reduced to 0.40, 0.724, and 1.03 for the same forecast periods. Similarly, the VAR prediction model without the NSI showed RMSE values of 1.6484, 0.6254, and 0.9220 for the 1-month, 2-month, and 3-month forecasts, respectively, while applying the NSI led to RMSE values of 1.1315, 0.3413, and 1.6227 for these periods. These results demonstrate the effectiveness of the proposed model in predicting apartment transaction price index and its ability to forecast real estate market price fluctuations that reflect socio-economic trends.