• Progress in Medical Physics
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• v.10 no.3
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• pp.133-140
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• 1999

In this paper, as a preliminary study for developing a full 3D electron dose calculation algorithm, We developed 2.5D electron dose calculation algorithm by extending 2D pencil-beam model to consider three dimensional geometry such as air-gap and obliquity appropriately. The dose calculation algorithm was implemented using the IDL5.2(Research Systems Inc., USA), For calculation of the Hogstrom's pencil-beam algorithm, the measured data of the central-axis depth-dose for 12 MeV(Siemens M6740) and the linear stopping power and the linear scattering power of water and air from ICRU report 35 was used. To evaluate the accuracy of the implemented program, we compared the calculated dose distribution with the film measurements in the three situations; the normal incident beam, the 45$^{\circ}$ oblique incident beam, and the beam incident on the pit-shaped phantom. As results, about 120 seconds had been required on the PC (Pentium III 450MHz) to calculate dose distribution of a single beam. It needs some optimizing methods to speed up the dose calculation. For the accuracy of dose calculation, in the case of the normal incident beam of the regular and irregular shaped field, at the rapid dose gradient region of penumbra, the errors were within $\pm$3 mm and the dose profiles were agreed within 5%. However, the discrepancy between the calculation and the measurement were about 10% for the oblique incident beam and the beam incident on the pit-shaped phantom. In conclusions, we expended 2D pencil-beam algorithm to take into account the three dimensional geometry of the patient. And also, as well as the dose calculation of irregular field, the irregular shaped body contour and the air-gap could be considered appropriately in the implemented program. In the near future, the more accurate algorithm will be implemented considering inhomogeneity correction using CT, and at that time, the program can be used as a tool for educational and research purpose. This study was supported by a grant (＃HMP-98-G-1-016) of the HAN(Highly Advanced National) Project, Ministry of Health & Welfare, R.O.K.

• Korean Journal of Plant Resources
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• v.36 no.2
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• pp.107-121
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• 2023

This study analyzed the polyphenol, flavonoid contents, antioxidant activity, anti-aging activity and phenol component contents of Saccharina japonica (SJ), Costaria costata (CC) extracts with hot water, 95% methanol, 95% prethanol for investigating possible utilization of SJ and CC extracts. The result revealed that the SJ and CC methanol extracts showed the highest polyphenol and flavonoid contents, 4.63 mg TAN/g, and 4.19 mg QUE/g respectively. Also, the SJ and CC methanol extracts showed higher antioxidant activity than prethanol and hot water extracts, whereas the ABTS radical scavenging activities were the highest in prethanol extracts (IC₅₀ = 15.4, 10.3 ㎍/µL). In anti-aging activity for evaluating the anti-wrinkle activity and skin whitening activity, the CC methanol extracts had high collagenase inhibitory activity (88.3%), and the SJ prethanol extracts showed higher elastase inhibitory activity (19.0%) compared to other extracts. Then the tyrosinase inhibitory activity was significantly higher in the SJ and CC methanol extracts (41.8, 30.3%, respectively), whereas prethanol extracts were the lowest. To identify the phenol component contents of SJ and CC extracts, 4-hydroxybenzoic acid, naringenin, naringin and nicotinic acid were measured using LC-MS/MS. As a result, the phenol contents were the highest in SJ methanol extract (4-hydroxybenzoic acid), SJ and CC prethanol extract (naringin and naringenin) and CC prethanol extract (nicotinic acid). Lastly, the antioxidant activity of SJ and CC showed high correlations with polyphenol and flavonoid contents (R = -0.946~0.883). These results suggest that prethanol or methanol extracts of SJ and CC have higher antioxidant activities, anti-aging activity and the potential to be used as material for health functional food and cosmetics.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.1
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• pp.95-112
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• 2020

This paper is to investigate how cognitive bias of college students and entrepreneurs relates to perceived risks and entrepreneurial opportunities that represent uncertainty, and how various cognitive bias and entrepreneurial efficacy In the same way. The purpose of this study is to find improvement points of entrepreneurship education for college students and to suggest problems and improvement possibilities in the decision making process of current entrepreneurs. This empirical study is a necessary to improve the decision-making of individuals who want to start a business at the time when various attempts are made to activate the start-up business and increase the sustainability of the existing SME management. And understanding of the difference in opportunity evaluation, and suggests that it is necessary to provide good opportunities together with the upbringing of entrepreneurs. In order to achieve the purpose of the study, questionnaires were conducted for college students and entrepreneurs. A total of 363 questionnaire data were obtained and demonstrated through structural equation modeling. This study confirms that there is some relationship between perceived risk and cognitive bias. Overconfidence and control illusions among cognitive bias have a significant relationship between perceived risk and wealth. Especially, it is confirmed that control illusion of college students has a significant relationship with perceived risk. Second, cognitive bias demonstrated some significant relationship with opportunity evaluation. Although we did not find evidence that excess self-confidence is related to opportunity evaluation, we have verified that control illusions and current status bias are related to opportunity evaluation. Control illusions were significant in both college students and entrepreneurs. Third, perceived risk has a negative relationship with opportunity evaluation. All students, regardless of whether they are college students or entrepreneurs, judge opportunities positively if they perceive low risk. Fourth, it can be seen from the college students 'group that entrepreneurial efficacy has a moderating effect between perceived risk and opportunity evaluation, but no significant results were found in the entrepreneurs' group. Fifth, the college students and entrepreneurs have different cognitive bias, and they have proved that there is a different relationship between entrepreneurial opportunity evaluation and perceived risk. On the whole, there are various cognitive biases that are caused by time pressure or stress on college students and entrepreneurs who have to make judgments in uncertain opportunities, and in this respect, they can improve their judgment in the future. At the same time, university students can have a positive view of new opportunities based on high entrepreneurial efficacy, but if they fully understand the intrinsic risks of entrepreneurship through entrepreneurial education and fully understand the cognitive bias present in direct entrepreneurial experience, You will get a better opportunity assessment. This study has limitations in that it is based on the fact that university students and entrepreneurs are integrated, and that the survey respondents are selected by the limited random sampling method. It is necessary to conduct more systematic research based on more faithful data in the absence of the accumulation of entrepreneurial research data. Second, the translation tools used in the previous studies were translated and the meaning of the measurement tools might not be conveyed due to language differences. Therefore, it is necessary to construct a more precise scale for the accuracy of the study. Finally, complementary research should be done to identify what competitive opportunities are and what opportunities are appropriate for entrepreneurs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1559-1565
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• 2005

The Purpose of this study was to investigate college students' attitude toward body weight control, health-related lifestyle and dietary behavior by their perception on body image and obesity index. The subjects were 871 nation- wide college students (330 male and 541 female students) participating in a nutritional education program via internet- A cross-sectional survey was conducted using a self-administered questionnaire via internet. The data were analyzed by a SPSS 10.0 program. Height and weight (p < 0.05), and the distribution of obesity index (p < 0.001) showed significant differences between male and female college students. As for self perception on body image, the necessity of body weight control and the experience of efforts to change the body weight, there were significant differences between male and female college students (p < 0.001). There were significant differences among groups by obesity index in the hours of exercise (p < 0.01), drinking (p < 0.01) and smoking (P < 0.001). As for methods of body weight control, all the groups by obesity index thought that program of body weight control by diet company is the most desirable method. Therefore, we must recognize that it is hard to correct health problems resulting from wrong lifestyle and dietary behavior fixed during college life and prepare a system for college students to obtain correct lifestyle and dietary behavior.

• The Korean Journal of Elementary Counseling
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• v.11 no.1
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• pp.71-91
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• 2012

The purpose of this study is investigate what effects of counseling program using children's poem on maladapted children in school on the children's self-esteem and school adjustment. For this, counseling programs using children's poem was developed and this counseling sessions were implemented to maladapted children in school and the research question to analyze the effect is as follows. First, what effect does the counseling program using children's poem have on the improvement of self-esteem of the maladapted children in school? Secondly, what effect does the counseling program using children's poem have on the school life of the maladapted children in school? The research target were maladapted children in school who are enrolled in the 4th grade in Elementary school. Through two different case studies, these students were selected after reflecting the opinions of the students' current homeroom teacher, parents, and friends. The counseling program using children's poem were conducted from June 2010 to July 2010, twice a week for a total number of 12 sessions. Each session consisted of 40 minutes and client's change process was explored. Through the counseling program using children's poem, this study collected data and examined the effectiveness of the program through comparing the results of the evaluated results of the language and behavior the target children responded, depth interviews with parents, friends, and teachers, behavior observation checklist, and the pre and post test results of the measurement tools. The results of this study is as follows. First, the counseling program using children's poem improved the self-esteem of the maladjusted child in school. Especially, among the sub-region of self-esteem, it was able to improve the domestic, social and academic self-esteem. Secondly, the counseling program using children's poem had a positive effect on the school adjustment of the maladjusted child in school. Among the sub-region of school adjustment, it had a positive change in the teacher relationships, peer relationships, and attitude. In addition, children's poem which was the reading material for the counseling program using children's poem was proven to work effectively in the counseling progress. Recitation and content of the children's poem promoted self-open of the client and as a result, it had a positive effect on improving relations with the counselor and this became the media that led to a successful counseling session. Therefore, I anticipate that this counseling program using children's poem will be actively used in counseling sessions through applying the results of this study and after revising the program so the counseling program could have a more efficient effect on self-esteem and school adjustment.

• The Korean Journal of Elementary Counseling
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• v.7 no.2
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• pp.101-115
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• 2008

The purposes of this study were to consist an anger control program in order to help children confirm and modify their cognitive errors in peer anger-provoking situations(Lee Mi-gyeong, 2006), that and to examine the effects of this program on anger-provoking experience, anger controllability and peer relationship. The cognitive-behavioral anger control program was consisted of 16 sessions. The focus of the program were placed on perceiving angry feelings, confirming automatic thinking and cognitive errors and acquiring how to correct the cognitive errors(1st-10th sessions), and checking cognitive errors in 13 anger-provoking situations and practicing way to correct the errors(11th-15th sessions). To examine the effects of the program, 10 children who had a lot of anger-provoking experiences, and were poor at anger control and faced difficulties with peer relationship were selected. The cognitive-behavioral anger control program was implemented for eight weeks, twice a week, 40 minutes each. The collected data were analysed by the ANOVA method using the SPSS and Kwakstat(Kwak Ho-wan, 1993). What cognitive errors children made and how they modified the errors during the program were checked. The findings of the study were as follows: The cognitive-behavioral anger control program served to cut down on the anger-provoking experiences, to improve their anger controllability, to boost their peer relationship, and that effect lasted till six weeks later. And the cognitive errors they made during the program were in the order as follows: stating the oughtness of their behavior, followed by naming, seeing everything in black and white, emotional judgment, mind reading, linking the situation to themselves, overgeneralizing, and hasty conclusion. The ways to correct the cognitive errors were in the order as follows: putting oneself in another's place, explaining in a different manner, looking for proof, thinking of it is so difficult to indure, thinging of there is moral to it, and thinking of how angry after passing time.

• Journal of The Korean Association For Science Education
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• v.25 no.4
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• pp.441-449
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• 2005

The purpose of this study was to examine the degree of cognitive conflict by learner personality and the method of presenting anomalous data to induce cognitive conflict. The participants of this study were 461 high school students. To arose cognitive conflict, an actual demonstration was done for half of the participants and a logical article for the rest. MBTI (Myers-Briggs Type Indicator) was used to find the learner personality types, and CCLT (Cognitive Conflict Level Test) was used to measure the degree of cognitive conflict aroused when anomalous data was confronted. The results of this study indicated that learner personality types influence the degree of cognitive conflict. First, participants were divided into two personality types via preferences on each of the four preference indices; extraversion (E) or introversion (I), sensing (S) or intuition (N), thinking (T) or feeling (F), judgment (J) or perception (P). The cognitive conflict scores of the thinking types were significantly higher than those of the feeling types. Participants were also divided four personality types according to personality functional types: ST, SF, NT and NF. SF type showed a significantly lower cognitive conflict score than any of the other types. According to the type of learner personality, cognitive conflict was influenced differently by the method of presenting anomalous data. For example, the judgment types had a higher cognitive conflict score by logical argument, and the perception types showed a higher score by demonstration. In conclusion, learner cognitive conflicts were influenced by personality types and the methods of presenting anomalous data.

• Journal of Korean Home Economics Education Association
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• v.24 no.1
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• pp.85-104
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• 2012

The purpose of this study was to carry out the career portfolio and the teacher-directed career exploration program in the unit of 'Industry and Career' of Technology·Home Economics and to find out how much those programs affect on career maturity and career identity in middle school students. The subjects were third-grade students who were selected at random from a middle school in Daegu. The subjects were divided into 60 for career portfolio group, 60 for teacher-directed group, and 60 for control group. Those programs were conducted totally in 9 sessions once or twice a week, and each session took 45 minutes. For pretest and post test, the questionnaire consisting of career maturity scale and career identity scale was used. To analyze data, ANCOVA was used and Scheffe test was conducted to examine significant differences between three groups. The main result of this study was the following : First, students who participate in the career portfolio and the teacher-directed career exploration program are more improved than those who have not been taught anything in determinacy and purpose of career maturity. Also, students who join in the career portfolio career exploration program are much more improved than those who join in the teacher-directed career exploration program in confidence and preparedness of career maturity. Second, students who join in the career portfolio career exploration program are more improved than those who join in the teacher-directed career exploration program in stability, goal directivity and assertiveness of career identity. Also students who participate in the lecture-oriented career exploration program are more improved meaningfully than those who have not been taught anything in the task orientation of career identity.

• Radiation Oncology Journal
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• v.26 no.3
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• pp.181-188
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• 2008

Purpose: In order to enhance the efficiency of respiratory gated 4-dimensional radiation therapy for more regular and stable respiratory period and amplitude, a respiration training system was designed, and its efficacy was evaluated. Materials and Methods: The experiment was designed to measure the difference in respiration regularity following the use of a training system. A total of 11 subjects (9 volunteers and 2 patients) were included in the experiments. Three different breathing signals, including free breathing (free-breathing), guided breathing that followed training software (guided-breathing), and free breathing after the guided-breathing (post guided-breathing), were consecutively recorded in each subject. The peak-to-peak (PTP) period of the breathing signal, standard deviation (SD), peak-amplitude and its SD, area of the one cycle of the breathing wave form, and its root mean square (RMS) were measured and computed. Results: The temporal regularity was significantly improved in guided-breathing since the SD of breathing period reduced (free-breathing 0.568 vs guided-breathing 0.344, p=0.0013). The SD of the breathing period representing the post guided-breathing was also reduced, but the difference was not statistically significant (free-breathing 0.568 vs. guided-breathing 0.512, p=ns). Also the SD of measured amplitude was reduced in guided-breathing (free-breathing 1.317 vs. guided-breathing 1.068, p=0.187), although not significant. This indicated that the tidal volume for each breath was kept more even in guided-breathing compared to free-breathing. There was no change in breathing pattern between free-breathing and guided-breathing. The average area of breathing wave form and its RMS in postguided-breathing, however, was reduced by 7% and 5.9%, respectively. Conclusion: The guided-breathing was more stable and regular than the other forms of breathing data. Therefore, the developed respiratory training system was effective in improving the temporal regularity and maintaining a more even tidal volume.

• Journal of Hospice and Palliative Care
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• v.8 no.2
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• pp.224-233
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• 2005

Purpose: This study was conducted to provide basic data for developing an effective strategy for cancer pain management by comparing the levels of barriers to pain management of metastatic or advanced cancer patient and their nurses. Methods: The subject of this study were 155 patients who were treated for metastatic or advanced cancer at one of three hospitals in Seoul from January 2004 to January 2005, and 153 nurses who take care of those patients. The levels of barriers to pain management were measured using a tool developed by Gunnarsdottir et al. (2002), 27 questions on a six point scale. The levels of stresses were measured using a tool modified from a stress response measurement reported by Goh Gyung-bong et al. (2000), 27 questions on a five point scale. The levels of barriers in cancer patients were analyzed using t-test and ANOVA, while the data obtained from patients and nurses were compared by t-test. Results: Higher levels of barriers to pain management were found in three groups: 'less than middle school,' 'not treated with anti-cancer chemotherapy,' and 'ECOG of 2.' The level (2.55) of barriers to pain management in the patient group was higher than that (1.76) of the nurse group. Both of the two groups had high levels of barriers in two variables: 'There is a danger of becoming addicted to pain medicine.' and 'Using pain medicine blocks your ability to know if you have any new pain.' There was not a significant difference in the levels of stresses between the two groups. Conclusion: It was found that, for effective cancer pain management practices, it would be necessary to provide cancer patients and their nurses with education and training about pain management and related barriers.