• 한국분말재료학회지
• /
• 제7권4호
• /
• pp.189-196
• /
• 2000

Effect of ball filling ratio on the behavior of balls motion and their collision characteristic in a tumbler-ball milling of metal powder are investigated by a computer simulation. The discrete element method and the extended Kelvin model composed of nonlinear spring and nonlinear dashpot were employed in the simulation. It can be possible that analysis of the individual balls motion in a three-dimensional actual mill by the two-dimensional model simulation, since the simulated trajectories of ball paths are in relatively good agreement with the actual ones. It knows that the balls motion in the tumbler-ball mill is strongly influenced by the surface conditions of the balls and mill container wall. The energy consumption of the individual balls during impact and the impact frequency of the individual balls increased with an increase in the ball filling ratio and showed maximum values at about 50-60% ball filling ratio, and then decreased.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.165.1-165
• /
• 2001

The evolution strategy is a good evolutionary algorithm to find the global optimum of a real-valued function. Since many engineering problems can be formulated as real valued function optimization, the evolution strategy is frequently employed in engineering fields. However, in many engineering optimization problems, an optimization parameter is often restricted in the bounded region between two specified values, the minimum and the maximum limit, respectively. Since an offspring individual is generated randomly around a parent individual during mutation process of the evolution strategy, an individual outside the search region can be generated even if the parent is inside the search region. This paper proposes two new boundary-handling techniques for evolution strategies. One is the ...

• 대한핵의학회지
• /
• 제35권4호
• /
• pp.224-230
• /
• 2001

EBM is "the conscientious, explicit and judicious use of current best evidence in mating decisions about the care of the individual patient. It means integrating individual clinical expertise with the best available external clinical evidence from systematic research." EBM is the integration of clinical expertise, patient values, and the best evidence into the decision making process for patient care. The practice of EBM is usually triggered by patient encounters which generate questions about the effects of therapy, the utility of diagnostic tests, the prognosis of diseases, or the etiology of disorders. The best evidence is usually found in clinically relevant research that has been conducted using sound methodology. Evidence-based medicine requires new skills of the clinician, including efficient literature-searching, and the application of formal rules of evidence in evaluating the clinical literature. Evidence-based medicine converts the abstract exercise of reading and appraising the literature into the pragmatic process of using the literature to benefit individual patients while simultaneously expanding the clinician's knowledge base. This review will briefly discuss about concepts of evidence medicine and method of critical appraisal of literatures.

• Mass Spectrometry Letters
• /
• 제7권3호
• /
• pp.64-68
• /
• 2016

Scanning electron microscopy combined with thermal ionization mass spectrometry (SEM-TIMS) was used to determine the precise isotope ratios of ultra-trace levels of uranium contained in individual microparticles. An advanced multiple ion counter system consisting of three secondary ion multipliers and two compact discrete dynodes was used for complete simultaneous ion detection. For verification purposes, using TIMS with complete simultaneous measurement, isotopes were analyzed in 5 pg of uranium of a certified reference material. A microprobe in the SEM was used to transfer individual particles from a NUSIMEP-7 sample to TIMS filaments, which were then subjected to SEM-TIMS and complete simultaneous measurement. The excellent agreement in the resulting uranium isotope ratios with the certified NUSIMEP-7 values shows the validity of SEM-TIMS with complete simultaneous measurement for the analysis of uranium isotopes in individual particles. Further experimental study required for investigation of simultaneous measurement using the advanced multiple ion counter system is presented.

• 영어어문교육
• /
• 제13권1호
• /
• pp.261-282
• /
• 2007

The purpose of this study is to investigate American traditional values and American culture in English education. The understanding of American culture in English education requires the analysis of world changes in the global age. The history of American English, the formation of American society, and the background of natural environment are described in relation to the traditional American values of the earliest settlers, such as multi-culture, individual freedom, frontier heritage in the West, equality of opportunity and wealth and material abundance. Hence the case studies of students' project presentations on the American culture in English education exemplify the reflection of American traditional values in the current American life and society. It is concluded that project-based method with regard to cultural studies in English education reveals very positive learning effects by driving students' interests and active participation through the student-centered, creative, and cooperative project presentations.

• 공학교육연구
• /
• 제10권2호
• /
• pp.106-117
• /
• 2007

Recently there has arisen an increasing world-wide emphasis on teaching ethics within the engineering curriculum. Much of the teaching has relied on the use of an American model emphasizing autonomy and professional identification. This paper argues that this model is inadequate when engineering is seen in a global perspective, because different cultural values are dominant throughout the world, some of which stand in sharp contrast to traditional Western values based on the primacy of the individual. A new global engineering ethics thus needs to be constructed which takes into account a variety of different cultural values and local circumstances, but which is able to serve as a uniting ethical foundation for engineers throughout the world. The paper suggests that the development of a global code of engineering ethics would be a fruitful way to pursue such a strategy.

• 아동학회지
• /
• 제24권4호
• /
• pp.55-69
• /
• 2003

This study analyzed the contents of reading textbooks of Chinese-Korean $1^{st}$, $4^{th}$, and $7^{th}$ graders in Yanji, China with reference to ecological systems and values. Results showed that the literature genre of Korean textbooks in China was predominantly novels/stories(38.5%) rather than essays(13.7%), poems/verses/rhymes(16.2%) or others(31.6%). Characters were classified into 9 categories and analyzed by Bronfenbrenner's ecological paradigm. It was found that Chinese-Korean textbooks included more characters belonging to exo- or macro-systems including school, community, and government while Korean textbooks emphasized the self or the family, both belonging to the micro-system. Values in Chinese-Korean textbooks emphasized community and government. Korean textbooks emphasized individual life. Differences were more pronounced in textbooks of the upper grades.

• Bulletin of the Korean Chemical Society
• /
• 제25권8호
• /
• pp.1165-1170
• /
• 2004

The applicability of the combined nearly ideal binary solvent/Redlich-Kister (CNIBS/R-K) equation for correlation of various solvatochromic parameters (SP) with composition is shown employing 84 experimental data sets for aqueous and organic binary solvent systems at temperatures ranging 15 to $75^{\circ}C$. The model provides a simple computational model to correlate/predict different SP values in various binary solvent systems. In proposed equations, $MPD_s$ (mean percentage deviations) are between 0.0500% and 6.9591% in mixtures of dimethyl sulfoxide with 2-methylpropan-2-ol and benzene with 2-methylpropan-2-ol, respectively. Correlation of the calculated and experimental values of various SP give an equation with an overall mean percentage deviation (OMPD) of 1.1900, $R^2$ = 0.99692, s.e = 0.01223 and F = 341925.51. Approximately 70% of the calculated SP values have IPD (individual percentage deviation) lower than one and it is possible to predict unmeasured SP values by using only eight experimental data.

• 산업융합연구
• /
• 제4권1호
• /
• pp.133-152
• /
• 2006

The objectives of this study are as follows. First, we try to find out if self-congruity between brand personality and self-image overall has significant influence on the attitude toward brand. Second, we figured out whether functional, experiential, and symbolic values have influence on the attitude toward brand. Third, we figured out if self-congruity between brand personality and self-image has significant influence on a functional, experiential, and symbolic values. Main results are as follows. Consumers tend to prefer certain brand of casual wears in accordance with their cognized brand-personality and self-image. Functional values of Bean-Pole, Hazzys, and Tommy's except Polo have positive influence on attitude toward brand. Experiential and symbolic values of all the four brands have positive influence on attitude toward brand. However, the influences of self-congruity between brand personality and self-image on individual brand varied.

• Korean Journal of Radiology
• /
• 제23권10호
• /
• pp.986-997
• /
• 2022

Objective: Whether metabolic redistribution occurs in patients with white matter hyperintensities (WMHs) on magnetic resonance imaging (MRI) is unknown. This study aimed 1) to propose a measure of the brain metabolic network for an individual patient and preliminarily apply it to identify impaired metabolic networks in patients with WMHs, and 2) to explore the clinical and imaging features of metabolic redistribution in patients with WMHs. Materials and Methods: This study included 50 patients with WMHs and 70 healthy controls (HCs) who underwent ¹⁸F-fluorodeoxyglucose-positron emission tomography/MRI. Various global property parameters according to graph theory and an individual parameter of brain metabolic network called "individual contribution index" were obtained. Parameter values were compared between the WMH and HC groups. The performance of the parameters in discriminating between the two groups was assessed using the area under the receiver operating characteristic curve (AUC). The correlation between the individual contribution index and Fazekas score was assessed, and the interaction between age and individual contribution index was determined. A generalized linear model was fitted with the individual contribution index as the dependent variable and the mean standardized uptake value (SUV_mean) of nodes in the whole-brain network or seven classic functional networks as independent variables to determine their association. Results: The means ± standard deviations of the individual contribution index were (0.697 ± 10.9) × 10^-3 and (0.0967 ± 0.0545) × 10^-3 in the WMH and HC groups, respectively (p < 0.001). The AUC of the individual contribution index was 0.864 (95% confidence interval, 0.785-0.943). A positive correlation was identified between the individual contribution index and the Fazekas scores in patients with WMHs (r = 0.57, p < 0.001). Age and individual contribution index demonstrated a significant interaction effect on the Fazekas score. A significant direct association was observed between the individual contribution index and the SUV_mean of the limbic network (p < 0.001). Conclusion: The individual contribution index may demonstrate the redistribution of the brain metabolic network in patients with WMHs.