• Title/Summary/Keyword: Internal stress model

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A study on reduction of springback defects in excavator tank cover part (굴삭기 Tank Cover 부품 뒤틀림 불량 저감에 대한 연구)

  • Jeon, Yong-Jun;Lee, Ha-Sung;Kim, Dong-Earn;Heo, Young-Moo
    • Design & Manufacturing
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    • v.12 no.1
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    • pp.52-57
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    • 2018
  • With the recent strengthening of environmental regulations and the need for cost reduction, excavators, a type of construction equipment, are being miniaturized while components are being developed in consideration of stability. In the case of excavator press parts, mainly high-strength steel sheets are being used to enhance stability and reduce weight. However, in the case of high-strength materials, there is a need to research product forming methods to reduce Springback in defects arising in parts assembly due to Springback that result from the internal residual stress that occurs in press forming being released after product forming. Accordingly, regarding the tank cover, an excavator press-forming part, this study selected a method to reduce distortion through analysis of the Springback occurrence rate and Springback causes through a forming analysis. A forming analysis was conducted for the Springback of the tank cover. Deformations of 13.714 mm in the upper part and 6.244 mm in the inner part of the product occurred, while wrinkles occurred on the sides of the product due to uneven thickness. A forming analysis was conducted for the major shapes of the product to investigate the causes of Springback. Distortion deformation due to the bead in the center of the product was confirmed to be a large factor. A Springback reduction method of correcting uneven thickness in the product sides, a Springback reduction method of removing the bead, and a correction method of restriking after the final forming were used in a forming analysis to determine the degree of Springback reduction. For the forming method to correct uneven thickness in the sides, deformation was reduced by 12% in the upper side compared to the existing model, but deformation in the inner side increased by 1%. For the restriking forming method, deformation decreased by 25% in the upper side and 13% in the inner side. For the bead removal method, deformation decreased by 28% in the upper side and 13% in the inner side, the largest Springback correction results. This indicates that the bead has a large affect on Springback.

Ganoderma Lucidum Pharmacopuncture for Teating Ethanol-induced Chronic Gastric Ulcers in Rats

  • Park, Jae-Heung;Jang, Kyung-Jun;Kim, Cheol-Hong;Kim, Jung-Hee;Kim, Young-Kyun;Yoon, Hyun-Min
    • Journal of Pharmacopuncture
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    • v.18 no.1
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    • pp.72-78
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    • 2015
  • Objectives: The stomach is a sensitive digestive organ that is susceptible to exogenous pathogens from the diet. In response to such pathogens, the stomach induces oxidative stress, which might be related to the development of both gastric organic disorders such as gastritis, gastric ulcers, and gastric cancer, and functional disorders such as functional dyspepsia. This study was accomplished to investigate the effect of Ganoderma lucidum pharmacopuncture (GLP) on chronic gastric ulcers in rats. Methods: The rats were divided into 4 groups of 8 animals each: the normal, the control, the normal saline (NP) and the GLP groups. In this study, the modified ethanol gastritis model was used. The rats were administrated 56% ethanol orally every other day. The dose of ethanol was 8 g/kg body weight. The normal group received the same amount of normal saline instead of ethanol. The NP and the GLP groups were treated with injection of saline and GLP respectively. The control group received no treatment. Two local acupoints CV12 (中脘) and ST36 (足三里) were used. All laboratory rats underwent treatment for 15 days. On last day, the rats were sacrificed and their stomachs were immediately excised. Results: Ulcers of the gastric mucosa appeared as elongated bands of hemorrhagic lesions parallel to the long axis of the stomach. In the NP and GLP groups, the injuries to the gastric mucosal injuries were not as severe as they were in the control group. Wound healings of the chronic gastric ulcers was promoted by using GLP and significant alterations of the indices in the gastric mucosa were observed. Such protection was demonstrated by gross appearance, histology and immunehistochemistry staining for Bcl-2-associated X (BAX), B-cell lymphoma 2 (Bcl-2) and Transforming growth factor-beta 1 (TGF-${\beta}1$). Conclusion: These results suggest that GLP at CV12 and ST36 can provide significant protection to the gastric mucosa against an ethanol induced chronic gastric ulcer.

The Validation of the Play Participation Attitude Scale for Parents of Preschoolers (영유아 부모의 놀이참여태도 척도 타당화 연구)

  • Lee, So-yean;Wui, Yeong-hee;Yoo, Jae-ryoung;Chyung, Yun-joo;Lee, Young-ae;Kim, Lee-jin
    • Korean Journal of Play Therapy
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    • v.21 no.4
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    • pp.491-507
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    • 2018
  • The purpose of this study is to validate the Play Participation Attitude Scale for parents of preschoolers, which was developed by the Delphi survey. 447 parents of 9 daycare centers in Seoul and Incheon were recruited for this study and, finally, data from 339 parents were used to perform exploratory factor analysis, confirmatory factor analysis, correlation analysis, multiple regression analysis, and reliability analysis. The results of the study are as follows. First, factor analyses revealed that the global fit of the sensitively play (7 items), responsively play (6 items), and delightfully play(7 items) three-factor model was good. Second, the internal consistency of the Play Participation Attitude Scale was good. Third, there was a statistically significant positive correlation between the current scale and the parents' playfulness scale, indicating concurrent validity. Finally, higher scores of the Play Participation Attitude Scale and its three factors significantly predicted lower scores of parenting stress and higher scores of the preschoolers' self-control ability. These findings revealed that this new measure to be both valid and reliable and specifically suggests what kind of attitude is appropriate for parents to adopt when participating in preschoolers' play.

Effects of Organizational Justice on Emotions, Job Satisfaction, and Turnover Intention in Franchise Industry (조직공정성이 감정, 직무만족 그리고 이직의도에 미치는 영향)

  • Han, Sang-Ho;Lee, Yong-Ki;Lee, Jae-Gyu
    • The Korean Journal of Franchise Management
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    • v.9 no.2
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    • pp.7-16
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    • 2018
  • Purpose - Turnover Intention in the franchise industry is becoming a very important issue. This study examines the structural relationships between organizational justice, emotion, job satisfaction, and turnover intention in the franchise industry. In this model, emotion was classified into two sub-dimensions such as positive and negative emotion. Research design, data, methodology - The sample of this study collected from employees of a food-service franchise company is representative. Copies of the questionnaire along with a cover letter were delivered by a research assistant to the human resources manager or the general manager of the selected food-service franchise firms after they agreed to participate in the study. In order to increase the response rate of the respondents, a small gift was provided to the respondents who completed the questionnaire. A total of 300 questionnaires were distributed and 285 returned responses, 9 responses were not usable due to missing information. Thus, a total of 276 responses were used using structural equation modeling with Smartpls 3.0. Results - The results showed that organizational justice had positive significant effects on positive emotion and job satisfaction. Job satisfaction had negative a significant effect on turnover intention. And negative emotion had positive significant effect on turnover intention. Conclusions - The results of this study provide some implications. If employees feel that the franchise headquarters is fair about the methods and procedures of decision making, resource allocation, information sharing, etc., it means that employees feel better. If the franchise's decision-making processes and methods and results are transparently disclosed and processed in accordance with the internal rules of the company, the employees will be able to fully understand and accept them. The results of this study also show that positive and negative emotions of service-based franchise employees have different effects on job attitude and organizational behavior. In particular, when negative emotions of employees are passed on to others and the results are negative, employees may feel that they are disoriented or wrong. Therefore, the franchise headquarters should try to inspire employees' sense of organizational community, and should pay attention to how to relieve the job stress and the fair distribution of work and rewards.

Factorial Validity of the Korean Version of the Illness Intrusive Rating Scale among Psychiatric Outpatients Mainly Diagnosed with Anxiety or Depressive Disorders (불안 및 우울장애를 주요 진단으로 하는 정신건강의학과 외래환자 대상 한국판 질병침습도 평가척도의 요인 타당도 연구)

  • Cho, Yubin;Kim, Daeho;Kim, Eunkyung;Jo, Hwa Yeon;Yun, Mirim;Lee, Hoseon
    • Korean Journal of Psychosomatic Medicine
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    • v.27 no.2
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    • pp.77-84
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    • 2019
  • Objectives : The Illness Intrusiveness Rating Scale (IIRS) is a well-validated self-report instrument for assessing negative impact of chronic illness and/or adverse effects of its treatment on everyday life domains. Although extensive literature probed its psychometric properties in medical illness, little attention was paid for its validity for psychiatric population. This study aimed to test factorial structure of the Korean Version of the IIRS (IIRS-K) in a consecutive sample of psychiatric outpatients. Methods : Data set of 307 first-visit patients of psychiatric clinic at Guri Hanyang univ. Hospital were used. Exploratory and confirmatory factor analysis, internal consistency were tested in IIRS-K. We also checked Spearman's correlation analysis between IIRS-K, Zung's self-report anxiety scale and Zung's self-report depression scale. Results : 76.9% of the patients were with anxiety disorder and depressive disorder. The principal component factor analysis of the IIRS-K extracted three-factor structure accounted for 63.2% of total variance that was contextually similar to the original English version. This three-factor solution showed the best fit when tested confirmatory factor analysis compared to the original IIRS, two-factor model of IIRS-K suggested from medical outpatients, and one-factor solution. The IIRS-K also showed good internal consistency (Cronbach's α=0.90) and good convergent validity with anxiety and depression scales. Conclusions : The IIRS-K showed the three-factor structure that was similar but not identical to original version. Overall, this study proved factorial validity of the IIRS-K and it can be used for Korean clinical population.

A Study of Teacher's Satisfaction Regarding Korean Medicine Doctor's Student Health and Wellness Program in 2016 - In Middle & High School of Seongnam City - (2016년도 한의 교의 프로그램의 교사들의 만족도에 관한 연구 - 성남시 중고등학교를 대상으로 -)

  • Sung, Hyun Kyung;Shin, Seon Mi;Go, Ho-Yeon;Ko, Jae-Un;Kim, Hyo-Sun;Choi, Suk-Hoon;Park, Jeong-Su
    • The Journal of Pediatrics of Korean Medicine
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    • v.32 no.1
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    • pp.83-91
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    • 2018
  • Objectives This study aims to build the baseline data for promoting school health care program by identifying satisfaction level and improvement point through the satisfaction survey after Korean medicine doctor's student health and wellness program in 2016. Methods An association of Korean medicine doctor in Seongnam city conducted Korean medicine doctor's student health and wellness program for 12 middle schools, 6 high schools and 1 special-need school in Seongnam city in 2016. The participating Korean medicine doctor visited each school for 8 times and conducted health consultations, health education classes and Korean medicine treatment for the school students and the school employees. Teachers and administrators from the participating schools answered the self-reported satisfaction questionnaires and the results were analyzed by SPSS 22.0. Results 35 people responded the program satisfaction questionnaires, the overall satisfaction average was $9.40{\pm}0.88$ (out of 10). In the course of the program, satisfaction average regarding the student's health check-ups was $9.05{\pm}0.88$, satisfaction average regarding the informatory brochures for the parents was $9.08{\pm}1.09$, satisfaction average regarding the participation enrollment process was $9.06{\pm}1.16$, and the satisfaction average regarding the questionnaire statistics and the result reports was $8.86{\pm}1.93$. The satisfaction average of the program was as follows: health consultation ($9.20{\pm}1.08$), treatment ($9.31{\pm}0.90$), and health education classes ($8.78{\pm}1.68$). Some of the good things about program were 'Telling students about their physical condition' (57.1%), 'Curing the sick student quickly' (48.6%), 'Providing students with useful information about the health' (48.6%), 'Teaching students how to manage their health and how to manage symptoms' (42.9%). Average satisfaction about sustainability and needs of the program was $9.15{\pm}0.91$, and the participant teachers wanted to learn more about how to manage internet addiction (22.9%), stress (45.7%), atopy (28.6%), neck pain (42.9%), allergic rhinitis (37.1%), and low back pain (34.3%) from the future wellness programs. Conclusions Student health care is one of the most important issue in national health policies. We have designed a bridge model that a local community, school, and doctors can work together to develop. After the implementation of the program, the results of the satisfaction survey showed a very high satisfaction level. This study can be the basis for further improvement of the bridge program as well as the expansion of the program in other settings.

PRELIMINARY STUDY OF MENTAL REPRESENTATIONS OF PRESCHOOL CHILDREN EXPERIENCING SINGLE, SEVERE TRAUMA (심한 정신적 외상 경험을 한 학령 전기 아동의 정신적 표상에 대한 예비연구)

  • Eon, So-Yong;Song, Won-Woung;Oh, Kyung-Ja;Choi, Eui-Gyum;Shim, Eun-Ji;Shin, Yee-Jin
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.15 no.1
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    • pp.61-74
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    • 2004
  • Objectives:This study was performed to introduce a psychoeducational family therapy model for the families of schizophrenic patient and to investigate the effect of this model on the changes in coping style and depressive symptoms of the family members, and in perception of emotional support by families and depressive symptoms of patients. Methods:Nine preschool children, 3-5 years old, experiencing physical injuries caused by attack from a psychotic patient at kindergarten, were evaluated for psychological assessments;Intelligence test, MSSB(MacArthur Story-Stem Battery), H-T-P test(House-Tree-Person test). And their parents completed rating scale, KPI-C(Korean Personality Inventory for Children about children’s psychological conditions). Results:With respects to the contents and emotional reactions of MSSB, 9 preschool children showed generally high levels of anxiety, depression, avoidance, aggression, probably related to the traumatic experiences. Even though children couldn't verbally report directly about their traumatic experiences, in both MSSB, structured play narrative assessment tool, and HPT, free drawing and association test, they demonstrated psychiatric problems through reenactment plays, regardless of clinical diagnoses. Conclusion:Present study allowed us the chance to see beyond the outer pathological behaviors of PTSD in preschool children, through deeper evaluations of their mental representation. These preliminary data suggest deep understanding of internal representation would be of help for thorough evaluations and treatment plan for preschool children, experiencing severe trauma.

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Analysis of Interactions in Multiple Genes using IFSA(Independent Feature Subspace Analysis) (IFSA 알고리즘을 이용한 유전자 상호 관계 분석)

  • Kim, Hye-Jin;Choi, Seung-Jin;Bang, Sung-Yang
    • Journal of KIISE:Computer Systems and Theory
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    • v.33 no.3
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    • pp.157-165
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    • 2006
  • The change of external/internal factors of the cell rquires specific biological functions to maintain life. Such functions encourage particular genes to jnteract/regulate each other in multiple ways. Accordingly, we applied a linear decomposition model IFSA, which derives hidden variables, called the 'expression mode' that corresponds to the functions. To interpret gene interaction/regulation, we used a cross-correlation method given an expression mode. Linear decomposition models such as principal component analysis (PCA) and independent component analysis (ICA) were shown to be useful in analyzing high dimensional DNA microarray data, compared to clustering methods. These methods assume that gene expression is controlled by a linear combination of uncorrelated/indepdendent latent variables. However these methods have some difficulty in grouping similar patterns which are slightly time-delayed or asymmetric since only exactly matched Patterns are considered. In order to overcome this, we employ the (IFSA) method of [1] to locate phase- and shut-invariant features. Membership scoring functions play an important role to classify genes since linear decomposition models basically aim at data reduction not but at grouping data. We address a new function essential to the IFSA method. In this paper we stress that IFSA is useful in grouping functionally-related genes in the presence of time-shift and expression phase variance. Ultimately, we propose a new approach to investigate the multiple interaction information of genes.

Effect of Attenuation Correction, Scatter Correction and Resolution Recovery on Diagnostic Performance of Quantitative Myocardial SPECT for Coronary Artery Disease (감쇠보정, 산란보정 및 해상도복원이 정량적 심근 SPECT의 관상동맥질환 진단성능에 미치는 효과)

  • Hwang, Kyung-Hoon;Lee, Dong-Soo;Paeng, Jin-Chul;Lee, Myoung-Mook;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.36 no.5
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    • pp.288-297
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    • 2002
  • Purpose: Soft tissue attenuation and scattering are major methodological limitations of myocardial perfusion SPECT. To overcome these limitations, algorithms for attenuation, scatter correction and resolution recovery (ASCRR) is being developed, while quantitative myocardial SPECT has also become available. In this study, we investigated the efficacy of an ASCRR-corrected quantitative myocardial SPECT method for the diagnosis of coronary artery disease (CAD). Materials and Methods: Seventy-five patients (M:F=51:24, $61.0{\pm}8.9$ years old) suspected of CAD who underwent coronary angiography (CAG) within $7{\pm}12$ days of SPECT(Group-I) and 20 subjects (M:F=10:10, age $40.6{\pm}9.4$) with a low likelihood of coronary artery disease (Group-II) were enrolled. Tl-201 rest/ dipyridamole-stress Tc-99m-MIBI gated myocardial SPECT was performed. ASCRR correction was peformed using a Gd-153 line source and automatic software (Vantage-Pro; ADAC Labs, USA). Using a 20-segment model, segmental perfusion was automatically quantified on both the ASCRR-corrected and uncorrected images using an automatic quantifying software (AutoQUANT; ADAC Labs.). Using these quantified values, CAD was diagnosed in each of the 3 coronary arterial territories. The diagnostic performance of ASCRR-corrected SPECT was compared with that of non-corrected SPECT. Results: Among the 75 patients of Group-I, 9 patients had normal CAG while the remaining 66 patients had 155 arterial lesions; 61 left anterior descending (LAD), 48 left circumflex (LCX) and 46 right coronary (RCA) arterial lesions. For the LAD and LCX lesions, there was no significant difference in diagnostic performance. In Group-II patients, the overall normalcy rate improved but this improvement was not statistically significant (p=0.07). However, for RCA lesions, specificity improved significantly but sensitivity worsened significantly with ASCRR correction (both p<0.05). Overall accuracy was the same. Conclusion: The ASCRR correction did not improve diagnostic performance significantly although the diagnostic specificity for RCA lesions improved on quantitative myocardial SPECT. The clinical application of the ASC-RR correction requires more discretion regarding cost and efficacy.

A Study on the Relationship between the Experience of Sanhujori, the Traditional Postpartal Care in Korea and Present Health Status of Chronic Arthritis Female Patient (만성관절염 여성 환자의 산후조리 경험과 건강상태와의 관계)

  • Yoo, Eun-Kwang;Lee, Sun-Hyae;Kim, Myoung-Hee
    • Women's Health Nursing
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    • v.4 no.2
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    • pp.217-230
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    • 1998
  • The purpose of this descriptive correlational study was to define the relationship between the experience of Sanhuujori, Korean traditional non-professional postpartal care after delivery and abortion and present health status of chronic arthritis female patient who visited to outpatient clinic of rheumatic internal medicine at a hospital located in Seoul, Korea. A convenience sample of 64 women who orally agreed to be a participant and data were collected form October 1996 to May, 1997 for sis months by way of interview with semistructured questionnaire. The data were analyzed by the SPSS pc program using t-test, ANOVA and Scheffe test as a post hoc and Pearson Correlation Coefficient. The results of the study were as follows ; Mean age of participants was 53.2 years and mean number of children was 3.1. Mean frequency of abortion was 2.1 times per woman. Seventy four percentage of respondents did not have Sanhujori after abortion. The mean period of Sanhujori after delivery was 17.7, 15.2, 13.8 days from the first child to third child and shorter than that of general woman such as 20.0, 19.0, 17.3 days in the previous study. On the subjective evaluation of whether the women did Sanhujori well or not, the rate of 'did Sanhujori wrongly' was the highest rank in each child where as general woman 'did Sanhujori well' at the first child, 'moderate' at the second and third child and 'did Sanhujori wrongly' at the 4th and fifth child. The health status implies both subjective health status women perceived and the rate of complaints of physical symptom distress women are experiencing presently. The respondents of 82.5% perceived them as unhealthy or sick and 68.9% of women complained more than two symptoms. Mean number of physical symptom distress women complained was 2.33. The main sites of physical symptom distress were upper & lower extremities 69.1% including knee and hand, whole body 19.1%, neck 3.7%, waist & shoulders 2.7% respectively. The characteristics of the symptoms were mostly pain 60%, swelling 19.8%, rigidity & deformity 7.9% respectively, sensation of heat 6.8% and weakness 1.7%. Women perceived the etiology of the chronic arthritis as stress 25.8%, 'did Sanhujori wrongly' & overwork 23.4% respectively, genetic 12.9%, malnutrition, 4.8%, and aging process 3.2%. There were significant positive correlation between subjective health status and the period of Sanhujori after delivery of the second child(r=-0.22) and negative correlation with the number of child at the level of 5% of significance statistically(r=0.27). There were significant negative correlation between the rate of complaints of physical symptom distress and the subjective evaluation whether she did Sanhujori well or not at the level of 5% of significance statistically(r=-0.23). And the rate of complaints of physical symptom distress in the group of women who experienced abortion was significantly higher than that of women who did not experience it at the level of 5% significance statistically(t=2.00) In conclusion, this finding reconfirmed the possible relationship between health status of chronic arthritis female patient and the experience of Sanhujori after delivery & abortion. It provides a challenge to the professional care givers to research further on the effects of Sanhujori on the health status, health recovery after abortion or delivery from the various aspects through the crosssectional and longitudinal research for the refinement of the reality of not only as cultural phenomenon but as conceptual model for the appropriateness of intervention and quality of care for desirable health outcomes.

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