• Communications for Statistical Applications and Methods
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• v.25 no.3
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• pp.321-328
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• 2018

In clinical trials with repeated measurements, the time-averaged difference (TAD) may provide a more powerful evaluation of treatment efficacy than the rate of changes over time when the treatment effect has rapid onset and repeated measurements continue across an extended period after a maximum effect is achieved (Overall and Doyle, Controlled Clinical Trials, 15, 100-123, 1994). The sample size formula has been investigated by many researchers for the evaluation of TAD in two treatment groups. For the evaluation of TAD in multi-arm trials, Zhang and Ahn (Computational Statistics & Data Analysis, 58, 283-291, 2013) and Lou et al. (Communications in Statistics-Theory and Methods, 46, 11204-11213, 2017b) developed the sample size formulas for continuous outcomes and count outcomes, respectively. In this paper, we derive a sample size formula to evaluate the TAD of the repeated binary outcomes in multi-arm trials using the generalized estimating equation approach. This proposed sample size formula accounts for various correlation structures and missing patterns (including a mixture of independent missing and monotone missing patterns) that are frequently encountered by practitioners in clinical trials. We conduct simulation studies to assess the performance of the proposed sample size formula under a wide range of design parameters. The results show that the empirical powers and the empirical Type I errors are close to nominal levels. We illustrate our proposed method using a clinical trial example.

• Journal of Families and Better Life
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• v.21 no.3
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• pp.61-73
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• 2003

The purpose of this study was to compare the consumption expenditure patterns and the effects of socioeconomic variables on expenditure between single-mother families and two-parent families. From the 2001 Household Income and Expenditure Survey conducted by Korea National Statistical Office (KNSO), 693 single-mother families and 14,439 two-parent families were selected. A t-test was completed to examine how the expenditure patterns of two types of families differ. Total expenditures and expenditures on 11 consumption categories were modeled as functions of permanent income and other socioeconomic variables. Also, dummy variable interaction technique was used to examine whether the independent variables differently affected the expenditures between single-mother families and two-parent families. The results of this study indicated that there were differences between single-mother and two-parent families in the levels and shares of expenditures of each consumption category, and the effects of socioeconomic variables on expenditures. Single-mother families had spent less than did two-parent families in each consumption category. However, single-mother families had significantly higher expenditure shares for food at home, shelter, utilities, apparel and shoes, and education. Income elasticities for food at home, shelter, utilities, and education of single-mother families were significantly larger than those of two- parent families.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.703-719
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• 2007

The purpose of this study were to analyze the consumption patterns of animal foods during the sixteenth century through Shamirok. There were eleven animal foods : beef, pork, chicken, pheasant, deer, roe, lamb, bear, fox, sparrow, and horse. The most frequently consumed were in the order of pheasant, doe, and chicken. There were 44 fish consumed, including flatfish, hairtail, mackerel, flounder, kumlin fish, bass, null fish, codfish, and red snapper, as well as four mollusks and six shellfish. Eggs and fish egg were also consumed. These foods were cooked as Tang(湯), Gui(灸), Po(脯), Hoe(膾), and Sookyook(熟肉), or processed after being dried or salted. The animal foods were mostly consumed as Po and Tang in daily eating and for formal dishes. Fish were mostly consumed as Jockgal or Shikhae. The foods were primarily acquired by donation from local officials or relatives ; secondly by independent poultry farming, fishing, or hunting, along with the production of grain and thirdly through barter with rice and textiles. Food were sometimes traded for profit, but such acts of trading while living ; as wartime refugees was a meager means for living.

• Journal of the Korea Society of Computer and Information
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• v.4 no.4
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• pp.113-119
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• 1999

Recently, design patterns have been known to be highly effective and practical. Design pattern is a collection of collaborating classes that captures the application independent behavior of system in a particular domain. By using design pattern, the development time and software quality can be greatly increased. However, systematic development process and detailed instructions of building design patterns have not been studied enough. In this paper. we propose practical intranet structure modeling technique that are based on design pattern. The proposed process consists of the four typical software development phases; analysis, navigation, interface, behavior domain design, and each phase is defined as a logical sequence of development tasks. Since the proposed process is based on design pattern foundation, and can be efficiently produced by applying this process.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.4
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• pp.1-10
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• 1993

In this paper, a new method of phoneme segmentation of handwritten Korean characters using the local graph pattern is proposed. At first, thinning was performed before extracting features. End-point, inflexion-point, branch-point and cross-point were extracted as features. Using these features and the angular relations between these features, local graph pattern was made. When local graph pattern is made, the of strokes is investigated on contacting point. From this process, pattern is simplified as contacting pattern of the basic form and the contacting form we must take into account can be restricted within fixed region, 4therefore phoneme segmentation not influenced by characters form and any other contact in a single character is performed as matching this local graph pattern with base patterns searched ahead. This experiments with 540 characters have been conducted. From the result of this experiment, it is shown that phoneme segmentation is independent of characters form and other contact in a single character to obtain a correct segmentation rate of 95%, manages it efficiently to reduce the time spent in lock operation when the lock.

• Electrical & Electronic Materials
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• v.10 no.7
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• pp.645-650
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• 1997

We manufactured CoNbZr/Cu/CoNbZr multi-layer films by rf magnetron sputtering methods and formed the patterns on the deposited multi-layer films. In this study, we fabricated a new etchant for forming the patterns by the wet etching with etchant and we searched for the best etching conditions and the etchant composition. Cu was etched selectively independent on the concentration of iron chloride solution, but amorphous CoNbZr thin film did not. The etchant was achieved by iron chloride solution(17.5 mol%) mixed with HF (20 mol%) during 150 sec, which etched CoNbZr/Cu/CoNbZr multi-layer films at the same time. Also, the etchant etched CoNbZr/Cu/CoNbZr multi-layer films by the three-step. It was shown that the cross-section had the isotropic structure and excellent etching characteristics with the above etchant.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.11
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• pp.1271-1284
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• 2011

This study improves the fitness of Air Force winter service uniforms through the development of a shirt pattern drafting method and automatic pattern drafting program for MTM production. A calculation formula is formed through a correlation analysis and regression analysis using Size Korea 2004 3D measurement data after analyzing 4 kinds of existing shirt pattern drafting methods and 3 types of shirt patterns currently used for the Air Force service uniform. The results of this study are as follows: The developed pattern drafting method has 4 parts that use calculated dimensions: neck base width, front interscye, back interscye and scye depth. Other body measuring parts that have a high correlation with calculation parts are inserted into regression analysis as independent variables to create dimension calculation formulas. The result of the final study patterns were better than existing winter service uniforms in nearly all items for the appearance evaluation and motion adaptability evaluations. The method was converted into an automatic pattern drafting program using C++ after the completion of pattern drafting method development.

• Nuclear Engineering and Technology
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• v.50 no.5
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• pp.767-772
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• 2018

Public acceptance is a major issue that will determine the future of nuclear energy. In this article, we review relevant studies and identify several common patterns of nuclear public acceptance. Based on these patterns and four categories of factors, we propose hypotheses on the impact of different socioeconomic factors on the public opinion of nuclear energy. These factors were demographic and social influences, politico-economic, energy conditions, and nuclear accidents and natural risks. We tested these hypotheses using a data set including survey results on public opinion of nuclear energy in 59 countries from 1987 to 2014. Results of the regression analysis generally verified the proposed hypotheses, especially regarding the positive impact of education or geological suitability and the negative effect of improved living standards and democracy on nuclear acceptance. We propose policy recommendations, including a better focus on education and communication and a thorough consideration of the social and geological conditions a country needs to make before deciding to go nuclear. Potential weaknesses of this study are also discussed, including the possible causal relation between independent variables and the binary nature of the dependent variable.

• International journal of thyroidology
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• v.11 no.2
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• pp.143-151
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• 2018

Background and Objectives: Sirtuins (SIRTs) play important roles in cellular and organismal homeostasis. They have distinct gene expression patterns in various cancers; however, the relationship between SIRT expression and the progression of thyroid cancer is unclear. We investigated the expression of SIRTs in patients with papillary thyroid carcinoma (PTC) and their role as biomarkers for predicting the aggressiveness of this disease. Materials and Methods: We used immunohistochemical staining to evaluate the expression of SIRT1 and SIRT3 in tumor specimens from 270 patients with PTC. We also evaluated the potential association between SIRT expression and diverse clinicopathological features. Results: High SIRT1 expression was negatively correlated with lymphovascular invasion, central lymph node metastasis, and lateral lymph node metastasis. Multivariate analyses revealed that high SIRT1 expression was a negative independent risk factor for lateral lymph node metastasis. By contrast, high SIRT3 expression was positively correlated with locoregional recurrence. Interestingly, when patients were grouped by tumor SIRT expression patterns, the group with low SIRT1 expression and high SIRT3 expression was correlated with more aggressive cancer phenotypes including central lymph node metastasis and lateral lymph node metastasis. Conclusion: Our results suggest that SIRTs play dual roles in tumor progression, and the combination of decreased SIRT1 expression and increased SIRT3 expression is significantly associated with a poor prognosis in patients with PTC.

• Journal of Korean Neurosurgical Society
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• v.65 no.1
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• pp.151-160
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• 2022

Continuous monitoring of intracranial pressure is a well established medical procedure. Still, little is known about long-term behavior of intracranial pressure in normal pressure hydrocephalus. The present study is designed to evaluate periodicity of intracranial pressure over long-time scales using intraventricular pressure monitoring in patients with normal pressure hydrocephalus. In addition, the circadian and diurnal patterns of blood pressure and body temperature in those patients are studied. Four patients, selected with "probable" normal pressure hydrocephalus, were monitored for several dozen hours. Intracranial pressure, blood pressure, and body temperature were recorded hourly. Autocorrelation functions were calculated and cross-correlation analysis were carried out to study all the time-series data. Autocorrelation results show that intracranial pressure, blood pressure, and body temperature values follow bimodal (positive and negative) curves over a day. The cross-correlation functions demonstrate causal relationships between intracranial pressure, blood pressure, and body temperature. The results show that long-term fluctuations in intracranial pressure exhibit cyclical patterns with periods of about 24 hours. Continuous intracranial pressure recording in "probable" normal pressure hydrocephalus patients reveals circadian fluctuations not related to the day and night cycle. These fluctuations are causally related to changes in blood pressure and body temperature. The present study reveals the complete loss of the diurnal blood pressure and body temperature rhythmicities in patients with "probable" normal pressure hydrocephalus.