• Journal of Radiation Protection and Research
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• v.18 no.2
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• pp.17-25
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• 1993

Beta ray spectra of $^3H,\;^{14}C\;and\;^{36}Cl$ in liquid scintillation counting system have been calculated using the Monte Carlo method by which physical behaviors of particle transport in medium were simulated. The calculations have been carried out on the basis of beta rays being slowing down according to the continuous slowing down approximation(CSDA) model. Beta rays generated in simulation geometry were traced until they lost their energy below 0.3keV that in known to be the detection limit in the liquid scintillation counter. Scintillator solution in which pure beta emitting radionuclides were dissolved uniformly was assumed to be bottled in the shape of right circular cylinder with 12.5mm in radius and 35mm in height. The comparison of the calculated and measured results showed satisfactory agreement between those two, with slight discrepancy due to self quenching in the case of lower energy of emitted beta particles in the solution.

• 한국노년학
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• v.29 no.1
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• pp.1-20
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• 2009

The purpose of the current research is to reconstruct the process in which changes in elderly support take place from the perspective of the elderly in rural areas. Six elderly couples were interviewed three times with the use of Schütze's 'autobiographical-narrative interview'. The entire interviews consisted of 17 sessions. Interviewed data was analyzed, following the method of Schütze's 'autobiographical-narrative interview analysis'. Research findings were as follows: Elderly support as experienced by the current elderly couples is mainly 'family support', which turned out to be 'dual structural shift' in the process of modernization. That is, there has been an 'internal structural shift' from 'family support on intergenerational, mutual support dimension' to 'family support on intragenerational self-support dimension' on the one hand. An 'external structural shift' has been noticed that realizes the 'socialization of family support' on the other hand. Additionally, a 'discrepancy' was captured between support norm and support behavior as occurred in the process of 'dual structural shift'. Perception on the 'dual structural shift' has proven 'ambivalent'. On the basis of these results, a critical discussion of modernization theory ensued, along with some implications for practice.

• Advances in nano research
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• v.15 no.5
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• pp.385-399
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• 2023

Hexagonal boron nitride (h-BN), commonly referred to as Boron Nitride Nanoribbons (BNNRs), is an electrical insulator characterized by high thermal stability and a wide bandgap semiconductor property. This study delves into the electronic properties of two BNNR configurations: Armchair BNNRs (ABNNRs) and Zigzag BNNRs (ZBNNRs). Utilizing the nearest-neighbour tight-binding approach and numerical methods, the electronic properties of BNNRs were simulated. A simplifying assumption, the Hamiltonian matrix is used to compute the electronic properties by considering the self-interaction energy of a unit cell and the interaction energy between the unit cells. The edge perturbation is applied to the selected atoms of ABNNRs and ZBNNRs to simulate the electronic properties changes. This simulation work is done by generating a custom script using numerical computational methods in MATLAB software. When benchmarked against a reference study, our results aligned closely in terms of band structure and bandgap energy for ABNNRs. However, variations were observed in the peak values of the continuous curves for the local density of states. This discrepancy can be attributed to the use of numerical methods in our study, in contrast to the semi-analytical approach adopted in the reference work.

• Progress in Medical Physics
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• v.9 no.4
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• pp.259-266
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• 1998

To achieve the 2D dose distribution around the designed high dose rate Ir-192 source substitution for Co-60 brachytherapy source, we determined the exposure rate constant and tissue attenuation factors as a large depth as a 20 cm from source center. The exposure rate constant is used for apparent activity in designed source with self-absorption and encapsulation steel wall. The tissue dose delivered from the 4401 segments of 2.5 mm in a diameter and 2.5 mm height of disk-type source layer. In the experiments, the tissue attenuation factors include the tissue attenuation and multiple scattering in a medium surrounding the source. The fitted the polynomial regression with 4th order for the tissue attenuation factors are very closed to the experimental measurement data within ${\pm}$1% discrepancy. The Meisberger's constant showed the large uncertainty in large distance from source. The exposure rate constant 4.69 Rcm$^2$/mCi-hr was currently used for determination of apparent activity of source and air kerma strength was obtained 0.973 for tissue absorbed dose from the energy spectrum of Ir-192 source. In our experiments with designed high dose rate brachytherapy source, the apparent activity of Ir-192 source was delivered from the 54.6 % of actual physical source activity through the self-absorption and encapsulation wall attenuations. This paper provides the 2-dimensional dose tabulation from unit apparent activity in a water medium for dose planning includes the multiple scattering, source anisotropy effect and geometric factors.

• Journal of Distribution Science
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• v.13 no.5
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• pp.83-90
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• 2015

Purpose - This research aims to understand the different behaviors of consumers according to cognitive age. Specifically, this research is focused on pro-social behavior. Pro-social behavior is defined as behavior benefiting others, rather than behavior benefiting one's self. It often entails individual risk or cost, such as when giving resources to others, waiting in line, asking for or paying a fair price, or risking one's life in battle. Therefore, we sought to understand consumer psychology and cognitive age as a reflection of inner psychology. People frequently perceive themselves as younger or older than their chronological ages. This self-perceived or cognitive age is a subjective age perception independent of actual chronological age. The discrepancy degree between chronological and cognitive age represents how much individuals perceive themselves as younger than they are. This study examines the gap in donation intention based on cognitive age. In order to investigate cognitive age, composed of four sub-categories (feel-age, look-age, do-age, and interest-age), this study explores the differential donation intention based on cognitive age, which determines the relationship between the young age and old age. Research design, data, and methodology - Data research was conducted by gathering 216 survey samples, excluding those with unreliable answers. Data coding and cleaning were used and SPSS 19.0 software for the data analysis. The respondents were categorized into two types, younger cognitive ages and older cognitive ages. Additionally, we analyzed the moderating variables. In particular, we used cognitive age degree and congruency level (cognitive age low vs. cognitive age high) × (congruency close vs. congruency distant) between - subjects design. First, regression was done to verify the difference between chronological age and cognitive age. Second, a t-test was done to verify the difference of cognitive age level in donations. Third, ANOVA (analysis of variance) was done to verify the difference between cognitive age and congruency in donations. Last, ANOVA was done to verify the difference between cognitive age and moral judgments in donations. Result - The results show most respondents perceive themselves as younger than their chronological ages. In particular, older respondents feel they are younger than their actual age. Moreover, the result of the comparison between low degree and high degree groups of cognitive age, show high donations at the higher degree of cognitive age groups. In addition, the closer the distance to the beneficiaries, the higher the donation in high degree cognitive age groups. The higher moral judgment groups also show relatively high contributions in lower degree cognitive age groups. Conclusions - Donations belong to the category of pro-social behavior reflecting an individual's psychological state. Therefore, it is important in understanding cognitive age. This study implies that it is necessary to take into account both cognitive age and chronological age when segmenting donors. Moreover, this study confirmed that there are different factors affecting the motives behind donations. Thus, it may be utilized to create differential donation strategies.

• Sleep Medicine and Psychophysiology
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• v.13 no.1
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• pp.15-21
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• 2006

Introduction: The objective of the present study was to investigate bedtime, rise time and time-in-bed of Korean college students, separately on weekday and on weekend and to compare them. In addition, this study also aimed to evaluate the influence of gender, age and grade on the above sleep parmeters in Korean college students. Methods: Information regarding bedtime and rise time, separately on weekday and on weekend, of Korean college students were obtained by self-administered questionnaire. Questionnaires of 1,825 students (1,416 females and 409 males, age 18-30；mean age $21.1{\pm}2.2$) were used for statistical analyses. Results: Korean college students retired to bed 50 minutes later (00：49 on weekday；01：40 on weekend；t=39.67, p<0.001), rose 1 hour 58 minutes later (07：52 on weekday；09：50 on weekend；t=39.46, p<0.001), and slept 1 hour 8 minutes longer (t=13.33, p<0.001) on weekend. Compared to male students, female students had earlier rise time (t=8.96, p<0.01；t=3.89, p<0.01) and earlier bedtime both on weekday and weekend (t=7.10, p<0.01；t=6.04, p<0.01), and shorter time-in-bed on weekday (t=1.99, p<0.01). In addition, rise time delay and time-in-bed increase on weekend were more prominent in female students than in male students (t=3.41, p<0.01; t=3.68, p<0.01). Grade was correlated with bedtime and rise time on weekday (${\beta}=0.1022$, p<0.01；${\beta}=0.1009$, p<0.01), bedtime and time-in-bed on weekend (${\beta}=0.1096$, p<0.01；${\beta}=-0.0990$, p<0.01), and differences between week-day and weekend of the rise time and the time-in-bed (${\beta}=-0.0906$, p<0.01；${\beta}=-0.1115$, p=0.02). Conclusions: In this study, Korean college students had earlier bedtime/rise time and shorter time-in-bed on weekday than on weekend. These findings suggest that weekday sleep-wake schedule of Korean college students may be advanced relative to their biological sleep-wake cycle and that this discrepancy may be associated with weekday sleep deprivation. In addition, differences of sleep patterns between weekday and weekend were more prominent in female students and students with lower grade. Therefore, discrepancy between weekday sleep-wake schedule and biological sleep-wake cycle, as well as weekday sleep deprivation, might be more serious in female or lower-grade students.

• Journal of Preventive Medicine and Public Health
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• v.31 no.2 s.61
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• pp.199-214
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• 1998

This study was undertaken to explain weight control behavior and intention of obese children and adolescents as measured by the elements of the health belief model. A total of 732 obese students from 28 schools in Seoul metropolitan area and their mothers were assessed with a self-administered questionnaire. The analyzed results are as follows; 1. Among obese students, 45.3% of male students and 57.2% of female students, a significantly higher portion than male students, reported that they had tried to lose weight within the recent year. Exercise was the most frequently used method to lose weight followed by diet control, drug use, and specialized clinic visits, in descending order. 2. Male students were more likely to try to lose weight if they perceived a low threat level and their mother had a job, and female students were more likely to try to lose weight if they were younger in age, perceived a low threat level and had strong external motivating factors. 3. Female students showed a significantly higher level of intention to obesity control than male students, and the intention level of their mothers also showed the same trend. 4. In male students, the degree of weight dissatisfaction, weight control experience, the level of obesity related beliefs of students, the educational level of the mother and economic status of the family were significant predictors of intention to obesity control, and in females, age, the level of obesity related beliefs of students and intention of their mothers were significant. In the mothers of male students, obesity index of students, age of the mother and the level of obesity related beliefs of the mother were significant predictors of intention of the mother, and in the mothers of female students, obesity index of students, occupational status of the mother and obesity related beliefs of the mother were significant. 5. According to the path model of intention to obesity control, the degree of weight dissatisfaction had the most powerful effect in male students, and perceived net benefit level was the most important variable in female students. Since the weight control behavior and intention of obese students were more predictable by the degree of weight dissatisfaction than the obesity index, we can conclude that only the students dissatisfied with their weight are well motivated for obesity control. There can be a discrepancy between the mother and her child's beliefs and intention status(especially in male students), so the therapists should also assess the student's opinion as well as the mother's. In female students, the perceived net benefit level wag the most important predictor of intention to obesity control, therefore the intervention program should pay particular attention to the positive benefits of weight control rather than negative aspects(threats) of obesity.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.2
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• pp.357-366
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• 2008

Posterior cross-bite is a relatively frequent malocclusion in primary and early mixed dentition and the reported prevalence of posterior cross-bite varies from 7% to 23%. It has been defined as a transverse discrepancy in arch relationship which the palatal cusp of the upper posterior teeth do not occlude in the central fossa of the opposing lower teeth, and can be manifested in a single tooth or in a group of teeth. Posterior cross-bite does not often self-correct and therefore immediate treatment is recommended. Occlusal adjustment to eliminate premature contact that causes mandibular deviation, expansion of narrow maxillary arch, arrangement of the individual teeth to treat asymmetry within the dental arch are the methods of treating cross-bite. In the present case, functional posterior cross-bite was observed in the primary and the early mixed dentition children. The children were treated by the slow maxillary expansion and occlusal adjustment. The outcome of periodic examinations after the correction of cross-bite was favorable.

• Health Policy and Management
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• v.10 no.4
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• pp.57-74
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• 2000

This study is conducted to compare how the Western.Oriental medical practitioners and health professionals perceive reciprocal development strategies respectively of Western.Oriental Medicine in Korea. A total of 3,273 persons were questioned by direct distribution, e-mail, and mail with a self-developed questionnaire. Of those questioned, 362 responded (the response rate of 11.1%), and of them n persons (Western medical practitioners 206, Oriental medical practitioners 90, and health professionals 64) were analyzed with SPSS for Windows. The results were as follows： The need for legislation on the mutual development system for Western.Oriental Medicine was recognized by 66.9% (218 persons) of respondents. Among them, largest group who agreed with this need was the health professionals. Western medical practitioners chose the "the difference of approach methods on the diseases between Western.Oriental Medicine" as their response, and Oriental medical practitioners ＆ health professionals selected "the indifference or bias of Western medical practitioners"as the reasons for the inactivity in developing a mutual system of Western.Oriental Medicine. Therefore, Western medical practitioners and health professionals selected the category of "the reformation of educational system", while Oriental medical practitioners selected the category of "the activation of joint research on Western.Oriental medical care" as the most important condition for setting a precedent. Also, Western medical practitioners preferred "cooperative health care system for Western medical care supported by Oriental medical care", but Oriental medical practitioners and health professionals preferred “cooperative health care system of Western.Oriental medicine on equal terms" In conclusion, Western '||'&'||' Oriental medical practitioners have to make every effort to close the gap between differing views through mutual understanding and respect if joint research of Western.Oriental medical care is to become a reality. The government should continuously enforce the health policy on development of a legal and systematic infrastructure for mutual development strategy of Western.Oriental Medicine in Korea.strategy of Western.Oriental Medicine in Korea.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2424-2434
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• 2009

This study, centering on public enterprises, has been conducted from 4 different perspectives such as grasping the effects that the factor precedent of the multi-rater feedback affects on the usefulness of evaluation and the effects that the usefulness of evaluation affects on the organizational achievement, checking on whether there is any discrepancy among the effects affecting on the usefulness of evaluation in accordance with the degree of advance training on the evaluation system, and being what kind of effects the usefulness of valuation that the appraised eventually understand affects on the organizational achievement. As result of the study, the factor precedent that are confidence of the appraisers and the support from CEO reasonably affected on the usefulness of evaluation, but the standard referred to evaluation was not reasonable. It became resultantly clear that the confidence of the appraisers held the effect of control from the verification of whether there is the effect of control between the factor precedent and the usefulness of evaluation in accordance with the degree of advance training. However, it turned out that the standard referred to evaluation and the support from CEO held no effect of control. As result, It was possible to confirm that the usefulness of evaluation in this study affects directly or indirectly to the organizational achievement such as organizational immersion, job satisfaction, self development opportunity, and organizational revitalization as influenced by the prior factors, and the advance training was partially effective on the adjusting effect.