• Title/Summary/Keyword: stepwise analysis

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An Investigation on the Assessment Tool and Status of Assessment in the 'Scientific Inquiry Experiment' of the 2015 Revised Curriculum (2015 개정 교육과정 '과학탐구실험' 평가 도구 및 평가 현황 탐색)

  • Baek, Jongho;Byun, Taejin;Lee, Dongwon;Shim, Hyeon-Pyo
    • Journal of The Korean Association For Science Education
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    • v.40 no.5
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    • pp.515-529
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    • 2020
  • 'Scientific inquiry experiments', which was newly created subjects in the 2015 revised curriculum, was expected in the aspect of learning science and developing core competences through science practices. Based on changed view of evaluation, assessments of a practice-centered subject 'Scientific inquiry experiments' should be try to conducted in various ways, but many challenges were reported. In this study, through analysis of current status of assessment of the subject, we intended to find the way of conducting and supporting 'Scientific inquiry experiments'. We collected assessment materials and explanatory description about them from 25 teachers who taught 'Scientific inquiry experiments' in 2018 and 2019. And we analyzed the cases with framework which were consisted with three main categories: elements, standards, methods of assessments. Also, we investigated how the results of assessment were utilized. For the validity, we requested verification of the results of our data analysis to experts of science education and science teachers. From them, we also collected their opinions about our analysis. As a result of the study, teachers assessed some elements of inquiry skills such as 'analysis and interpreting the data', 'conducting inquiry' more than others which were closely related to what subject-matter the teachers used to organized inquiry program with. In the aspect of domain of assessments, though cognitive domain and affective domain as well as skills were evaluated, we also found that the assessment of those domains had some limitation. In terms of standard of assessment, the goals of assessment were presented in most cases, but there were relatively few cases which had the specific criteria and the stepwise statements of expected performance of students. The time and subject of the assessment were mainly post-class and teachers, and others such as in-class assessments, peer-assessments were used only in specific contexts. In all cases, the results of assessments used for calculating students' grade, but in some cases, we could observe that the results used for improving teaching and feedback for students. Based on these results, we discussed how to support the assessments of 'Scientific inquiry experiments'.

Factors Related with Job Satisfaction in Workers - Through the Application of NIOSH Job Stress Model - (직장인의 직무만족도 관련요인 분석 - NIOSH의 직무스트레스 모형을 적용하여 -)

  • Kim, Soon-Lae;Lee, Bok-Im;Lee, Jong-Eun;Rhee, Kyung-Yong;Jung, Hye-Sun
    • Research in Community and Public Health Nursing
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    • v.14 no.2
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    • pp.190-199
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    • 2003
  • This study was conducted to determine the factors affecting job satisfaction in workers by using the Job Stress Model proposed by the National Institute for Occupational Safety and Health (NIOSH). Data were collected from December 1 to December 30, 1999. The subjects were 2,133 workers employed at 155 work sites, who were examined using NIOSH Job Stress questionnaire translated by the Korea Occupational Safety ${\pounds}|$ Health Academy and Occupational Safety ${\pounds}|$ Health Research Institute. SAS/PC program was used for statistical analysis using descriptive analysis. Pearson's correlation coefficient, ANOVA, and Stepwise multiple regression analysis. The results of this study were as follows. 1. According to general characteristics of the subjects, job satisfaction was high in those with less number of children. 2. By work condition, job satisfaction was higher in those who were working in a permanent job position, were working with regular time basis than with shift basis, were working in regular shift hours than in changing shift hours, were working for a short period, and were working less hours and overtime works per week. 3. In terms of physical work environment, job satisfaction was significantly related to 10 physical environmental factors. In other words, job satisfaction was high in workers who were working in an environment with no noise, bright light, temperature adjusted to an appropriate level during summer and winter, humidity adjusted to an appropriate level. well ventilation, clean air, no exposure to hazardous substance during work hour, overall pleasant work environment and not crowded work space. 4. By work-related factors, job satisfaction was high in those with less ambiguity about future job and role, high job control/autonomy, and less workload. On the other hand, job satisfaction was low in those with little utilization of competencies, and much role conflict at work and workload. 5. As for the relationships between job satisfaction and the non-work related factors, job satisfaction was high in workers who were volunteering at different organizations or active in religious activities for 5-10 hours per week. 6. In the relationships between job satisfaction and buffering factors, significantly positive correlations were found between job satisfaction and factors such as support by direct superior, support by peers, and support by spouse, friend and family. 7. There were nine factors that affected job satisfaction in the workers: age, number of children, work hours per week, noise, temperature at the work site during summer, uncomfortable physical environment, role ambiguity, role conflict, ambiguity in job future, work load, no utilization of competencies and social support from direct supervisor. These nine factors accounted for 26% of the total variance in the multiple regression analysis. In conclusion. the following are proposed based on the results of this study. 1. The most important physical environmental factors affecting job satisfaction in workers were noise, role ambiguity, and work load, suggesting a need to develop strategies or programs to manage these factors at work sites. 2. A support system that could promote job satisfaction is needed by emphasizing the roles of occupational health nurses who may be stationed at work sites and manage the factors that could generate job stress. 3. Job satisfaction is one of the three acute responses to stress proposed in NIOSH job stress model (job satisfaction. physical discomfort and industrial accidents). Therefore, further studies need to be conducted on the other two issues.

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Factors Related to Serum Vitamin C Level in Terminally Ill Cancer Patients (말기암환자에서 혈청 비타민 C 농도와 연관된 인자들)

  • Kim, Hyung Jun;Hwang, In Cheol;Yeom, Chang Hwan;Ahn, Hong Yup;Choi, Youn Seon;Lee, Jae Jun;Lim, Su Hyuk
    • Journal of Hospice and Palliative Care
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    • v.17 no.4
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    • pp.241-247
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    • 2014
  • Purpose: Serum vitamin C is one of the indicators for antioxidant levels in the body and it is lower in cancer patients compared with the healthy population. However, there have been few studies on the levels of serum vitamin C in terminally ill cancer patients and related factors. Methods: We followed 65 terminal cancer patients who were hospitalized in two palliative care units. We collected data of age, sex, cancer type, functional status, clinical symptoms, history of cancer therapy, and various laboratory findings including serum vitamin C level. Patients were categorized into two groups according to the quartile of serum vitamin C level (Q1-3 vs. Q4), which were compared each other. Stepwise multiple logistic regression analysis was used to identify factors related to serum vitamin C levels. Results: The mean serum vitamin C level was $0.44{\mu}g/mL$, and all patients fell into the category of vitamin C deficiency. Univariate analysis showed that The serum vitamin C level was lower in non-lung cancer patients (P=0.041) and febrile patients (P=0.034). Multivariate analysis adjusted for potential confounders such as lung cancer, fever, dysphagia, dyspnea, C reactive protein, and history of chemotherapy demonstrated that odds for low serum vitamin C level was 3.7 for patients receiving chemotherapy (P=0.046) and 7.22 for febrile patients (P=0.02). Conclusion: Vitamin C deficiency was very severe in terminally ill cancer patients, and it was associated with history of chemotherapy and fever.

Biological Monitoring of Paint Handling Workers exposed to PAHs using Urinary 1-Hydroxypyrene (다핵방향족탄화수소류에 노출된 페인트 취급 근로자에서 요 중 1- Hydroxypyrene을 이용한 생물학적 모니터링)

  • Lee, Jong-Seong;Kim, Eun-A;Lee, Yong-Hag;Moon, Deog-Hwan;Kim, Kwang-Jong
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.15 no.2
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    • pp.124-134
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    • 2005
  • To investigate the exposure effect of polynuclear aromatic hydrocarbons (PAHs), we measured airborne total PAHs as an external dose, urinary 1-hydroxypyrene (1-OHP) as an internal dose of PAHs exposure, and analyzed the relationship between urinary 1-OHP concentration and PAHs exposure. The study population contained 44 workers in steel-pipe coating and paint manufacture industries. The airborne PAHs was obtained during survey day, and urine were sampled at the end of shift. Personal information on age, body weight, height, eniployment duration, smoking habit, and alcohol consumption was obtained by a structured questionnaire. Airborne PAHs were analyzed by the gas chromatograph with mass selective detector. Urinary 1-OHP levels were analyzed by the high performance liquid chromatograph with ultraviolet wavelength detector. For statistical estimation, t-test, ${\chi}^2$-test, analysis of variance, correlation analysis, arid regression analysis were executed by SPSS/PC (Windows version 10). The mean of environmental total PAHs was $87.8{\pm}7.81{\mu}g/m^3$. The mean concentration ($526.5{\pm}2.85{\mu}g/m^3$) of workers in steel-pipe coating industries using coal tar enamel was the higher than that ($17.5{\pm}3.36{\mu}g/m^3$) of workers in paint manufacture industries using coal tar paint. The mean of urinary 1-OHP concentration ($51.63{\pm}3.144{\mu}\;mol/mol$ creatinine) of workers in steel-pipe coating industries was the higher than that ($2.33{\pm}4.709{\mu}\;mol/mol$ creatinine) of workers in paint manufacture industries. The mean of urinary 1-OHP concentration of smokers was the higher than that of non-smokers. There was significant correlation between the urinary concentration of 1-OHP and the environmental concentration of PAHs (r=O.S48, p<0.001), pyrene(r=0.859, p<0.001), and urinary cotinine (r=0.324, p<0.05). The regression equation between the urinary concentration of 1-OHP in ${\mu}g/g$ creatinine($C_{1-OHP}$) and airborne concentration of PAHs (or pyrene) in ${\mu}g/m^3$ ($C_{PAHs}$ or Cpyrene) is: Log ($C_{1-OHP}$)=-0.650+0.889×Log($C_{PAHs}$), where $R^2=0.694$ and n=38 for p<0.001.Log ($C_{1-OHP}$)=1.087+0.707${\times}$Log(Cpyrene), where $R^2=0.713$ and n=38 for p<0.001. From the results of stepwise multiple regression analysis about 1-OHP, significant independents were total PAHs and urinary cotinine (adjusted $R^2=0.743$, p<0.001). In this study, there were significant correlation between the urinary concentration of 1-OHP and the airborne concentration of PAHs. The urinary 1-OHP was effective index as a biomarker of airborne PAHs in workplace. But it was influenced by non-occupational PAHs source, smoking.

An Analytical Study of the Quality of Life in Dental Hygienists in Seoul (서울지역 치과위생사의 삶의질(Quality of Life)에 관한 분석 연구)

  • Kim, Yeun-Sun
    • Journal of dental hygiene science
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    • v.5 no.1
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    • pp.39-43
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    • 2005
  • This study was carried out to provide fundamental data for an examination of a health promotion program by determining the influence of the Health Promoting Lifestyle Profile on the quality of life of female dental hygienists. The sample was selected from the population of 1,148 who were registered in the Association of Seoul Dental Hygienists. 800 subjects were randomly selected from 25 districts in Seoul. The data was collected by calling the dental hygienists to, explaining the contents and objective of our study, and sending them a questionnaire by post. The questionnaire consists of the total number of 97 questions: 62 questions on the Health Promoting Lifestyle Profile, 26 questions on the quality of life and 9 general characteristics questions. The data was collected from August 16 to October 15, 2004. Out of 800 subjects, 481(60.1%) completed the questionnaires. For statistical analysis, the frequency, percentage, arithmetic mean, ANOVA, and multiple regression analysis, were analyzed using the SAS 8.1 Analysis program. The significance level was set to 0.05. The results of this study were as follows: First, The average score of the subjects' quality of life was 3.1. For the sub-categories, it was shown that the degree of satisfaction on the condition of society was the highest at 3.2, and the degree of satisfaction on the condition of the individuals was the lowest at 3.1. The average score of the Health Promoting Lifestyle Profile variable was 2.5. For the sub-categories, it was shown that the degree of sanitary life was at 3.2, and degree of the professional health maintenance was the lowest at 1.7. Second, There were significant differences in the Quality of Life benefits of action with the general characteristics. There were significant differences in age, educational level, income, marital status, career, and Perceived Health Status. There were significant difference in Health Promoting Lifestyle Profile benefits of action with the general characteristics. There were significant differences in terms of age, educational level, income, marital status, career, and the Perceived Health Status. Finally, The stepwise multiple regression analysis revealed that the powerful predictors were Health Promoting Lifestyle Profile, income and the Perceived Health Status. These factors accounted for 37.6% of the variance in the Quality of Life patterns. As the subjects were limited to dental hygienists in Seoul, care should be taken when applying these results to all dental hygienists in Korea. In order to generalize the study, a large number of subjects selected from all regions in Korea will be needed.

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A Study on the Prediction Model of Stock Price Index Trend based on GA-MSVM that Simultaneously Optimizes Feature and Instance Selection (입력변수 및 학습사례 선정을 동시에 최적화하는 GA-MSVM 기반 주가지수 추세 예측 모형에 관한 연구)

  • Lee, Jong-sik;Ahn, Hyunchul
    • Journal of Intelligence and Information Systems
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    • v.23 no.4
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    • pp.147-168
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    • 2017
  • There have been many studies on accurate stock market forecasting in academia for a long time, and now there are also various forecasting models using various techniques. Recently, many attempts have been made to predict the stock index using various machine learning methods including Deep Learning. Although the fundamental analysis and the technical analysis method are used for the analysis of the traditional stock investment transaction, the technical analysis method is more useful for the application of the short-term transaction prediction or statistical and mathematical techniques. Most of the studies that have been conducted using these technical indicators have studied the model of predicting stock prices by binary classification - rising or falling - of stock market fluctuations in the future market (usually next trading day). However, it is also true that this binary classification has many unfavorable aspects in predicting trends, identifying trading signals, or signaling portfolio rebalancing. In this study, we try to predict the stock index by expanding the stock index trend (upward trend, boxed, downward trend) to the multiple classification system in the existing binary index method. In order to solve this multi-classification problem, a technique such as Multinomial Logistic Regression Analysis (MLOGIT), Multiple Discriminant Analysis (MDA) or Artificial Neural Networks (ANN) we propose an optimization model using Genetic Algorithm as a wrapper for improving the performance of this model using Multi-classification Support Vector Machines (MSVM), which has proved to be superior in prediction performance. In particular, the proposed model named GA-MSVM is designed to maximize model performance by optimizing not only the kernel function parameters of MSVM, but also the optimal selection of input variables (feature selection) as well as instance selection. In order to verify the performance of the proposed model, we applied the proposed method to the real data. The results show that the proposed method is more effective than the conventional multivariate SVM, which has been known to show the best prediction performance up to now, as well as existing artificial intelligence / data mining techniques such as MDA, MLOGIT, CBR, and it is confirmed that the prediction performance is better than this. Especially, it has been confirmed that the 'instance selection' plays a very important role in predicting the stock index trend, and it is confirmed that the improvement effect of the model is more important than other factors. To verify the usefulness of GA-MSVM, we applied it to Korea's real KOSPI200 stock index trend forecast. Our research is primarily aimed at predicting trend segments to capture signal acquisition or short-term trend transition points. The experimental data set includes technical indicators such as the price and volatility index (2004 ~ 2017) and macroeconomic data (interest rate, exchange rate, S&P 500, etc.) of KOSPI200 stock index in Korea. Using a variety of statistical methods including one-way ANOVA and stepwise MDA, 15 indicators were selected as candidate independent variables. The dependent variable, trend classification, was classified into three states: 1 (upward trend), 0 (boxed), and -1 (downward trend). 70% of the total data for each class was used for training and the remaining 30% was used for verifying. To verify the performance of the proposed model, several comparative model experiments such as MDA, MLOGIT, CBR, ANN and MSVM were conducted. MSVM has adopted the One-Against-One (OAO) approach, which is known as the most accurate approach among the various MSVM approaches. Although there are some limitations, the final experimental results demonstrate that the proposed model, GA-MSVM, performs at a significantly higher level than all comparative models.

THE EFFECT OF ADHD CHILD MOTHER'S DEPRESSIVE MOOD, PARENTING STRESS, AND PARENTING RELATED ATTITUDE ON PARENTING BEHAVIOR (주의력결핍과잉행동장애 아동 어머니의 우울감, 양육 스트레스 및 양육 관련 태도가 양육 행동에 미치는 영향)

  • Choi, Yoon-Young;Cho, Sun-Mi;Hong, Sung-Do;Oh, Eun-Young;Kim, Ji-Hae
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.13 no.1
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    • pp.153-162
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    • 2002
  • Summary:This study was designed to examine the effect of mother's depressive mood and parenting related attitude on parenting behavior, focusing on the cases having an ADHD child. Method:A total of 82 parents, 31 parents having children with ADHD and 51 normal, were involved in this study. The children of ADHD and normal group were 6-11 years old. ADHD group were diagnosed as attention-deficit hyperactivity disorder by psychiatric doctor and psychological evaluations using DSMIV criteria and the normal group were excluded by using Diagnostic Rating Scale-Parent, Teacher Form. The mothers of both group completed a series of questionnaire about mother's depressive mood and parenting-related attitude. To investigate the relationships between each variables, Student's t-test, correlation, stepwise regression, and hierarchical regression analysis were performed. Result:In correlation analysis, Mothers with an ADHD child were likely to report more coercive parenting behavior, more negative parenting-related attitudes, and depressive mood than normal group. In regression analysis, mother's parenting stress, dysfunctional thoughts, parenting competence, and depressive mood predicted coercive parenting behavior significantly, total explaining 50% of its variance, and especially depressive mood explained 29% of their coercive parenting behavior. These Results indicated that mother's depressive mood accounted for a substantial portion of coercive parenting behavior. Conclusion:These findings suggested that it is significantly important to reduce Mother's depressive mood through dealing with parenting sense of competence and dysfunctional thoughts, so, both parent education program and cognitive-behavioral therapeutic approach are needed to change parent's coercive parenting behavior. Finally, limitation of the present study and suggestions were discussed for further studies.

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A Neurobehavioral Performance Assessment in Lacunar Infarction Case-control Study (열공성 뇌경색 환자-대조군에서 신경행동검사의 수행 평가)

  • Kim, Ham-Gyum;Park, Sue-Kyung;Lee, Kun-Sei;Kim, Hyeoug-Su;Kim, Wha-Sun;Chang, Soung-Hoon
    • Journal of Preventive Medicine and Public Health
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    • v.36 no.3
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    • pp.255-262
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    • 2003
  • Objectives : We carried out tests for neurobehavior by using WHO-NCTB (neurobehavioral core test battery) and Perdue pegboard score test to identify differences between lacunar infarction cases and controls. Methods : Among the subjects who underwent MRI between February 2001 and March 2002 in a university hospital located in Seoul and who were diagnosed only as lacunar infarction without any intracranial disease, 46 patients were selected as cases (male: 21, female: 25). Controls were selected who had no cerebrovascular disease on MRI by matching age (5 years), gender, and education (2 years) in a ratio of 1:1 , Among WHO-NCTB, the following 5 tests and Perdue pegboard score test were used to categorize the study subjects: digit and symbol matching, simple reaction time, Benton visual retention, digit span, and Pursuit aiming test, Results : Among the above 6 tests of neurobehavior, lacunar infarction cases showed lower score than controls except for the simple reaction time test. As the controlling variables of multivariate analysis in the stepwise regression analysis, the followings were selected due to their significant association: age, education, BMI, gender, drinking, exercise, add systolic blood pressure. From multivariate regression analysis, there was significant difference (p<0.05) between lacunar infarction cases and controls in digit and symbol matching, Benton visual retention, digit span, pursuit aiming, and Perdue pegboard score test, but not in the score of simple reaction time test. Conclusions : We suggest that the above 5 tests for neurobehavior, with the exception of the simple reaction time test, might be used as the basis for recommendation of further treatment and other neurological tests by the earlier defection for neurological abnormality in lacunar infarction.

Big Five Personality in Discriminating the Groups by the Level of Social Sims (심리학적 도구 '5요인 성격 특성'에 의한 소셜 게임 연구: <심즈 소셜> 게임의 분석사례를 중심으로)

  • Lee, Dong-Yeop
    • Cartoon and Animation Studies
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    • s.29
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    • pp.129-149
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    • 2012
  • The purpose of this study was to investigate the clustering and Big Five Personality domains in discriminating groups by level of school-related adjustment, as experienced by Social Sims game users. Social Games are based on web that has simple rules to play in fictional time and space background. This paper is to analyze the relationships between social networks and user behaviors through the social games . In general, characteristics of social games are simple, fun and easy to play, popular to the public, and based on personal connections in reality. These features of social games make themselves different from video games with one player or MMORPG with many unspecific players. Especially Social Game show a noticeable characteristic related to social learning. The object of this research is to provide a possibility that game that its social perspective can be strengthened in social game environment and analyze whether it actually influences on problem solving of real life problems, therefore suggesting its direction of alternative play means and positive simulation game. Data was collected by administering 4 questionnaires (the short version of BFI, Satisfaction with life, Career Decision-.Making Self-.Efficacy, Depression) to the participants who were 20 people in Seoul and Daejeon. For the purposes of the data analysis, both Stepwise Discriminant analysis and Cluster analysis was employed. Neuroticism, Openness, Conscientiousness within the Big Five Personality domains were seen to be significant variables when it came to discriminating the groups. These findings indicated that the short version of the BFI may be useful in understanding for game user behaviors When it comes to cultural research, digital game takes up a significant role. We can see that from the fact that game, which has only been considered as a leisure activity or commercial means, is being actively research for its methodological, social role and function. Among digital game's several meanings, one of the most noticeable ones is the research on its critical, social participating function. According to Jame Paul gee, the most important merit of game is 'projected identity'. This means that experiences from various perspectives is possible.[1] In his recent autobiography , he described gamer as an active problem solver. In addition, Gonzalo Francesca also suggested an alternative game developing method through 'game that conveys critical messages by strengthening critical reasons'. [2] They all provided evidences showing game can be a strong academic tool. Not only does a genre called social game exist in the field of media and Social Network Game, but there are also some efforts to positively evaluate its value Through these kinds of researches, we can study how game can give positive influence along with the change in its general perception, which would eventually lead to spreading healthy game culture and enabling fresh life experience. This would better bring out the educative side of the game and become a social communicative tool. The object of this game is to provide a possibility that the social aspect can be strengthened within the game environment and analyze whether it actually influences the problem solving of real life problems. Therefore suggesting it's direction of alternative play means positive game simulation.

A Study for Alexithymia in the Patients with Panic Disorder (공황장애환자에서 감정표현불능증에 대한 연구)

  • Choi, Young-Hee;Jang, Hyuck-Jin;Kim, Min-Sook
    • Korean Journal of Psychosomatic Medicine
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    • v.14 no.1
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    • pp.53-61
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    • 2006
  • Objectives: This study was designed to evaluate difference of the alexithymia between panic patients and normal controls by examination of the relationships between different components of the alexithymia construct and level of anxiety and depression in panic patients and normal controls. Methods The subjects were 167 patients who met DSM-IV criteria for panic disorder and 110 normal controls. They drew up symptom checklists and self-rating scales, and were measured by Anxiety Disorders Interview Schedule-Panic attack & Agoraphobia(ADIS-P & A), Korean version of Toronto Alexithymia Scale (TAS-20K), Spielberger State-Trait Anxiety Inventory-State & Trait (STAI-S & T), Beck Depression Inventory (BDI), and Revised Anxiety Sensitivity Index (ASI-R). For statistical analysis, we performed t-test to compare the sociodemographic characteristics and the scores of self reported scales between panic patients and normal controls. Pearson correlation was performed between TAS-20K and it's subfactors, STAI-S & T, ASI-R and BDI in panic patients and normal controls. And stepwise multiple regression analysis was preformed to explain results of correlation analysis for alexithymia. Results: The panic patients reported more significant alexithymic (p<0.001), more difficulty identifying feeling (p<0.001) and describing feeling (p=0.001) than normal controls. Futhermore, panic patients were more significant anxious, sensitive to anxious feeling and depressive than normal controls. Moreover, the alexithymia of panic patients was explained by trait-anxiety $({\Delta}R^2=0.255)$ and anxiety sensitivity $({\Delta}R^2=0.062)$, that of normal controls was predicted by depression $({\Delta}R^2=0.144)$ and anxiety sensitivity $({\Delta}R^2=0.033)$ Conclusion: The panic patients reported more anxious and sensitive to anxious feeling, and these symptoms predict alexithymia in panic patients. However, the alexithymia of normal controls was explained by depression more than anxiety sensitivity, and such a result isn't consistent with previous studies and this may be mainly due to difference of the homogeneity in object of the studies.

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