• 제목/요약/키워드: Differential correlation

검색결과 453건 처리시간 0.026초

결정립크기와 집합조직제어를 통한 마그네슘 합금의 기계적 성질 개선 (Improvement of Mechanical Properties of Mg alloys through Control of Grain Size and Texture)

  • 김우진;이종범;김우영;정하국;박종덕
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2006년도 춘계학술대회 논문집
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    • pp.57-58
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    • 2006
  • The effects of lowering ECAP temperature during ECAP process and Post-ECAP annealing on microstructure, texture and mechanical properties of the AZ31 alloys have been investigated in the present study. The as-extruded materials were ECAP processed to 2 passes at 553K prior to subsequent pressing up to 6 passes at 523K or 493K. When this method of lowering ECAP temperature during ECAP was used, the rods could be successfully deformed up to 6 passes without any surface cracking. Grain refinement during ECAP process at 553K might have helped the material to endure further straining at lower deformation temperatures probably by increasing the strain accommodation effect by grain boundary sliding, causing stress relaxation. Texture modification during ECAP has a great influence on the strength of Mg alloys because HCP metals have limited number of slip systems. As slip is most prone to take place on basal planes in Mg at room temperature, the rotation of high fraction of basal planes to the directions favorable for slip as in ECAP decreases the yield stress appreciably. The strength of AZ31 Mg alloys increases with decrease of grain size if the texture is constant though ECAP deformation history is different. A standard positive strength dependence on the grain size for Mg alloys with the similar texture (Fig. 1) supports that the softening of ECAPed Mg alloys (a negative slope) typically observed despite the significant grain refinement is due to the texture modification where the rotation of basal planes occurs towards the orientation for easier slip. It could be predicted that if the original fiber texture is restored after ECAP treatment yielding marked grain refinement, yield stress as high as 500 MPa will be obtained at the grain size of ${\sim}1{\mu}m$. Differential speed rolling (DSR) with a high speed ratio between the upper and lower rolls was applied to alter the microstructure and texture of the AZ31 sheets. Significant grain refinement took place during the rolling owing to introduction of large shear deformation. Grain size as small as $1.4{\mu}m$ could be obtained at 423K after DSR. There was a good correlation between the (0002) pole intensity and tensile elongation. This result indicates that tensile ductility improvement in the asymmetrically rolled AZ31 Mg alloys is closely related to the weakening of basal texture during DSR. Further basal texture weakening occurred during annealing after DSR. According to Hall-Petch relation shown in Fig. 1, the strength of the asymmetrically rolled AZ31 is lower than that of the symmetrically rolled one when compared at the same grain size. This result was attributed to weakening of fiber texture during DSR. The DSRed AZ31, however, shows higher strength than the ECAPed AZ31 where texture has been completely replaced by a new texture associated with high Schmid factors.

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만성 질환이 자아개념 (Self Concept)과 신체상(Body Image)에 미치는 영향 -천식 환아를 중심으로- (A Study of the Influence of illness on Body Image and Self Concept -Specifically in Children with Asthma-)

  • 장효순
    • 대한간호학회지
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    • 제12권2호
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    • pp.80-90
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    • 1982
  • This study was undertaken to determine the influence of a chronic disease on body image, and to show that body image is directly related to one's self concept. Body image is the concept of one's own body based on present and past perception, and is elated to one's self concept. Body image is a dynamic concept constantly changing throughout the life cycle but it changes greatly in illness, surgery, and accident. The child with a chronic disease experiences pain and immobilization due to illness and he/she experiences a strange environment in the hospital. illness often brings feeling of frustration and loss of self-esteem. Therefore this study was done to compare the body image of a child with a chronic disease(Asthma), with that of a normal healthy child, and to determine the relationship between the body image and self concept. The subjects in this study were 36 children being treated for asthma at the allergy clinic of Y University Hospital in Seoul (patient group) and 44 children attending elementary school in Kwanak Ku Seoul (normal healthy group). For the measurement of the body image, the researcher used Secord & Jourard's Body Cathexis Scale, and another scale which was constructed after reading about Osgood's Semantic Differential Method. For the measurement of the self concept, the researcher used Jacox & Stewart's Health Self Concept. The period for data collection was from October 7th to October 27th, 1982. The analysis of data was done by use of Percentage, t-test, Chi-square test, Pearson Correlation Coefficient and ANOVA, The results of the study were as follows: 1. The first hypothesis,“That the chronically ill (Asthma) child will have a more negative body image than the normal healthy child.”was supported. 2. The second hypothesis,“The more negative the body image, the lower the self concept.”was also supported. 3. The researcher failed to obtain statistically significant results in the analysis of the general characteristics which affect the body image except in the case of the older child as compare to the younger Child having a mole positive body image (r=.2751, r=.2481, p<.05). However it was found that, 1) Boy's have a more positive body image than girls (Mean=〔37.81, 141.09〕,〔37.00, 126.54〕), 2) The child who has been hospitalized has a more negative body image than the child who has never been hospitalized (Mean=〔33.25, 122.45〕,〔35.68, 129.93〕). 3) The younger the child when the disease is discovered and diagnosed, the more negative the body image (Onset of illness: Mean=〔31.44, 117.33〕,〔34.00, 103.50〕, 〔35.75, 140.38〕,〔36.33, 130.00〕, Time of Diagnosis: Mean=〔29.00, 117.33〕,〔33.89, 115.00〕,〔33.36, 124.93〕,〔37.10, 139. 20〕). In conclusion the chronically ill(.Asthma) child has a more negative body image than the normal healthy child, and the more negative the body image the lower the self concept. Therefore the concept of body image is useful in understanding the influences of chronic disease on body' image and self concept.

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뇌졸중 환자의 말, 언어장애 선별에 대한 검사자간 신뢰도 및 훈련효과 (Inter-rater Reliability and Training Effect of the Differential Diagnosis of Speech and Language Disorder for Stroke Patients)

  • 김정완
    • 한국콘텐츠학회논문지
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    • 제11권9호
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    • pp.407-413
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    • 2011
  • 뇌졸중 환자의 실어증 유무를 정확히 판별하고 환자의 미세한 언어적 변화를 적절히 관찰하기 위해서는 일차적으로 신뢰로운 검사도구를 사용하여야 하고, 또한 검사자가 해당 도구의 사용에 있어 충분히 숙지하고 있어야 한다. 본 연구에서는 뇌졸중 환자의 실어증 및 말장애 유무의 진단에서 검사자의 전공영역에 따른 관찰자간 신뢰도를 살펴보고 훈련 전과 후의 차이를 비교해보고자 하였다. 이를 위해, 침상에 있는 뇌졸중 환자 46명을 대상으로 언어치료사, 신경과 전공의, 그리고 간호사 각각 4명씩 총 12명이 동시에 실어증 및 말장애 유무를 평가하였다. 연구 결과, 서로 다른 전공 영역의 전문가들 간에 말명료도 과제와/아/모음연장발성 과제의 '음질' 영역에서만 'acceptable'로 나타났고, 나머지 하부검사 영역에서는 'good-excellent'로 나타났다. 관찰자간 신뢰도가 'acceptable'로 나타난 과제들에 대해 3주간의 비디오 훈련 전후의 점수 차이를 비교하였다. 그 결과, 훈련 후 말명료도 과제에서 검사자들 간의 평정 점수의 차이는 유의하게 줄어들었으며, '음질' 평정의 정확성도 유의하게 증가하였다. 임상 경험 정도와 각 하부검사에 대한 평정 정확성 간의 상관관계를 알아본 결과, 언어치료사들은 임상 경험 정도가 증가할수록 그림설명하기 과제와 말명료도 과제에서, 그리고 의사 및 간호사들은 그림설명하기 과제에서 판정 정확도가 높아지는 것으로 나타났다. 결론적으로, 이 연구 결과는 뇌졸중 환자의 의사소통장애 진단에 있어 신경언어장애 환자 중, 특히 말장애환자에 대한 꾸준한 경험과 훈련이 반드시 필요하며, 훈련을 통해 평정 신뢰도를 확보할 수 있음을 시사한다.

낭성 종양의 체액에 대한 생체내, 생체외 3T 양성자 자기공명분 광법과 양성자 핵자기공명기법의 비교: Preliminary Study (Comparison of in Vivo, in Vitro 3T MR Spectroscopy and Proton NMR Spectroscopy for the Fluid from Cystic Tumor: Preliminary Study)

  • 이희중;김종열;장용민
    • Investigative Magnetic Resonance Imaging
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    • 제12권2호
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    • pp.107-114
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    • 2008
  • 목적 : 3T MR 기기를 이용하여, 췌장 주위에 발생한 낭성 종양에 대하여, 생체내, 그리고 생체외 생체내 자기공명분광법(magnetic resonance spectroscopy: MRS)를 획득한 후, 생체외 핵자기공명 (nuclear magnetic resonance, NMR) 스펙트럼을 기준으로 비교함으로써, 낭성 종양의 감별 진단에 있어 MRS의 적용 가능성을 알아보고자 하였다. 대상 및 방법 : 췌장 주위에 발행한 12예의 낭성 종양(점액성 낭성 종양=5, 췌담관내 유두종=5, 가성 낭종=1, 및 림프관종 n=1)을 대상으로 3.0T 생체내, 생체외 양성자 MRS 및 9T NMR 스펙트럼을 획득하였다. NMR의 피크와 상응하는 생체내, 생체외 양성자 MRS에서 관찰되는 피크의 존재유무를 알아보았으며, 특정 질환을 예측하는 피크에 대하여 알아보았다. 결과 : 생체내 MRS는 NMR과 민감도 29.6%, 특이도 82.6% 그리고, 67.7%의 정확도를 보였으며 (p=0.096, McNemar test), 생체외 MRS는 생체내 MRS는 민감도 57.1%, 특이도 92.6%, 그리고, 82.3%의 정확도를 보였다 (p = 0.362, McNemar test). 질병간의 스펙트럼의 차이는 NMR에서 췌담관내 유두종의 경우에서 점액성 낭성 종양에 비해 3.5-4.0 ppm에서 유의하게 많은 피크를 보였다 (p=0.026). 결론 : 결론적으로, NMR 이용한 화학물질 분석은 낭성 종양의 감별 진단에 도움이 될 가능성이 있는 기법으로 생각되지만, 생체내 및 생체외 MRS는 임상에 적용되기 위해서는 많은 기술적 발전을 필요로 하는 것으로 생각된다.

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산욕기 초산모의 어머니 역할획득에 관한 연구 (Maternal Role Attainment of Primiparous During the Postpartum Period)

  • 이은숙
    • 모자간호학회지
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    • 제2권1호
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    • pp.5-20
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    • 1992
  • This study was undertaken to identify the levels and affecting factors of the maternal role attainment(MRA) in the primipara during the postpartum period. The healthy ninety primiparous from the one university hospital and two local clinics in KwangJu city were selected and two Semantic Differential Scales (SD-Myself as Mothers, SD-My Baby) and the Pharis Self Confidence Scale were used in this study. Questionnaires were distributed at the 3rd days and the 4-6 weeks of the primiparous not showing any complication after normal delivery. The data collected were analysed statistically using t-test, Pearson's Product Moment Correlation Coefficient and ANOVA. The results obtained were summarized as follows; 1) On the 3rd day after the delivery, the scores of SD-myself as mother, SD-baby and Pharis Self Confidence were 70.6 points, 73.6 points and 78.6 points, respectively, showing the low level of MRA. 2) On the 4-6 weeks after delivery, the score of SD-myself as mother, SD-baby and Pharis Self Confidence were 72.8 points, 77.9 points, and 86.9 points, respectively, indicating the moderate level of MRA. 3) The mean scores of the SD scale and the Pharis Self Confidence during the postpartum periods were higher than those of the 3rd days, showing the SD-myself as mother (t=-2.09, P<.05), SD-baby(t=-4.12, P<.001), Pharis Self Confidence(t=-6.59, P<.001), respectively. 4) Positive correlations (r=.24$\sim$.69) were shown in the concepts related to the MRA and the cognitive-motor skill components and cognitive-affective skill components of the MRA became harmonious over time. 5) The relationships between the score of the MRA and the demographic and obstetric variables were as follows ; a) the score of the MRA in the twenties was higher than those of the thirties. b) the group with higher educational background showed higher MRA socres than the group with lower one. c) those who wanted pregnancy sustenance had higher MRA scores than those who did not. d) the group that did think of festus-feature represented higher MRA scores than those who did not. e) the group of mothers who have the daughters showed higher MRA scores than those who have boys. It can be concluded from the results that the MRA in the primiparous increased gradually, and that the cognitive-motor skills and cognitive-affective skills became harmonious over time. The level of the MRA was affected partly by the mothers general, obstetrical variables. Following suggestion were made oil the basis of the present study ; a) The longitudinal study on the MRA is needed. b) Multivariate analyses should be done for the identification of the factors influcening on the MRA. c) Education program for primiparous mother should be designed and developed to improve the MRA.

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Eosinophilia in Pleural Effusions: a Speculative Negative Predictor for Malignancy

  • Chu, Fang-Yeh;Liou, Ching-Biau;Sun, Jen-Tang;Bei, Chia-Hao;Liou, Tse-Hsuan;Tan, N-Chi;Yu, Yun-Chieh;Chang, Chih-Chun;Yen, Tzung-Hai;Su, Ming-Jang
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권3호
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    • pp.1411-1414
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    • 2016
  • Background: Eosinophilic pleural effusion (EPE) is an eosinophil count more than 10% on cytology of pleural samples. Recently, it was reported that malignancy had been the most prevalent cause inducing EPE. Therefore, we conducted an analysis on the prevalence and etiology of EPE and investigated the relationship between EPE and malignancy. Materials and Methods: Data for pleural cell differential count from patients receiving thoracentesis during the period from January 2008 to December 2013 were compared with clinical data and established diagnosis of patients obtained via electronic chart review. Results: A total of 6,801 requests of pleural cytology from 3,942 patients with pleural effusion who had received thoracentesis were available at Far Eastern Memorial Hospital from 2008 to 2013, and of these subjects, 115 (2.9%) were found to have EPE. The most frequent cause of EPE was malignancy (33.0%, n=38), followed by parapneumonic effusions (27.8%, n=32), tuberculosis pleuritis (13.9%, n=16), transudate effusions (12.2%, n=14) and the presence of blood or air in pleural space (10.4%, n=12). Additionally, an inverse relationship of eosinophilia in pleural fluid was identified in patients with malignancy and EPE. The cut-off eosinophil count in pleural fluid was 15% for the most accurate discrimination between malignancy and benign disorders in patients with EPE. At the cut-off level, the sensitivity and specificity were 65.8% and 67.5%, respectively. Conclusions: Pleural fluid eosinophilia was a speculative negative predictor for malignancy, despite the fact that cancers, including lung cancers and metastatic cancers to lung, were the most leading cause of pleural fluid eosinophilia. An inverse correlation was observed between the pleural eosinophil percentage and the likelihood of malignancy in patients with EPE.

Effects of Mastitis on Buffalo Milk Quality

  • Tripaldi, C.;Palocci, G.;Miarelli, M.;Catta, M.;Orlandini, S.;Amatiste, S.;Di Bernardini, R.;Catillo, G.
    • Asian-Australasian Journal of Animal Sciences
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    • 제23권10호
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    • pp.1319-1324
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    • 2010
  • The objectives of this study were to compare the effectiveness of different indicators of mammary inflammation in buffalo and to evaluate the association of the indicators with buffalo milk yield, composition, and rennet coagulation properties. This study was carried out at four buffalo farms in central Italy using a total of 50 lactating buffalo. Milk from each buffalo was tested at the beginning, middle, and end of lactation. To evaluate the relationship between mastitis markers and milk components, three classes were defined for each of the following markers: total somatic cell count (TSCC), differential somatic cell count (DSCC), and bacteriological results The regression coefficient for the reference method and the alternative method of determining TSCC was 0.81, indicating that the method routinely used to analyze buffalo milk consistently underestimated actual TSCC. The milk samples positive for udder-specific bacteria also had higher TSCC values than the samples that were negative for bacteria ($872{\times}10^3$/ml vs. $191{\times}10^3$/ml). In samples that were positive for udder-specific bacteria, polymorphonuclear leukocytes (PMN) made up greater than 50% of the cells. Moreover, only 1% of the samples in the lowest TSCC class were positive for bacteria. The correlation between TSCC and PMN was stronger (0.70), and PMN values in buffalo milk increased significantly when the TSCC class changed from low (38%) to medium and high (56% and 64%). Milk yield was negatively related to TSCC. Significant changes in lactose (4.87%, 4.80% and 4.64%) and chloride content (0.650 mg/ml, 0.862 mg/ml and 0.882 mg/ml) were also observed with increasing TSCC values. Higher TSCC was associated with impaired rennet coagulation properties: the clotting time increased, while the curd firming time ($p{\leq}0.05$) and firmness decreased. We concluded that in buffalo as in dairy cows, TSCC is a valid indicator of udder inflammation; we also confirmed that a value of $ 200{\times}10^3 cells/ml should be used as the threshold value for early identification of an animal affected by subclinical mastitis. In addition to its association with significantly decreased milk yield, a TSCC value above this threshold value was associated with changes in milk composition and coagulating properties.

알킬기의 길이가 콜레스테릴 4-n-알콕시벤조에이트의 열적-액정 특성에 미치는 영향 (Effect of Length of Alkyl Group on Thermal-Liquid Crystalline Properties of Cholesteryl 4-n-Alkoxybenzoate)

  • 윤두수;방문수
    • 한국산학기술학회논문지
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    • 제18권10호
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    • pp.69-74
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    • 2017
  • 본 연구에서는, 화합물의 액정 형성을 위한 메소젠기로써 콜레스테릴기를, 고체에서 액정상으로의 열 전이온도를 조절하기 위한 구조로써 알킬기를 포함하고 있는 콜레스테릭 액정 화합물인 콜레스테릴 4-n-알콕시벤조에이트 (Chol-n)를 합성하고, 이들 분자 내에 있는 알킬기의 탄소 사슬의 길이가 액정 화합물의 물성에 미치는 영향을 조사하였다. 합성된 액정화합물의 화학 구조와 열적 성질 및 액정성은 적외선 분광분석 (FT-IR), $^1H$-핵자기공명 분광분석 ($^1H$-NMR), 시차주사열량분석 (DSC) 그리고 편광현미경 (POM)을 이용하여 조사되었다. 연구 결과에 의하면, 합성된 화합물들의 용융 전이온도 ($T_m$)는 $103{\sim}143^{\circ}C$였고, 화합물 Chol-6을 제외한 모든 화합물들은 약 $60{\sim}100^{\circ}C$의 넓은 액정상 온도 구간을 나타냈으며, 분자내의 탄소 원자 수와 화합물의 열적 성질 사이의 상관성은 발견할 수 없었다. 합성된 모든 화합물들은 양방성 콜레스테릭 액정상을 보였고, 화합물 Chol-6, 8, 9, 및 10은 카이랄 스멕틱 액정상을 동반하였다. 그리고, 모든 화합물들은 액정 상태에서, 온도가 높아질수록 붉은 색 계통에서 푸른 색 계통으로 색이 변하는, 열 변색 현상을 나타내었다.

cDNA 마이크로어레이에서 유전자간 상관 관계에 대한 보고 (A Report on the Inter-Gene Correlations in cDNA Microarray Data Sets)

  • 김병수;장지선;김상철;임요한
    • 응용통계연구
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    • 제22권3호
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    • pp.617-626
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    • 2009
  • 최근에 보고되는 일련의 연구는 Affymetrix 마이크로어레이 자료에서 유전자간 상관관계가 강하고 장범위(長範圍)(long-ranged)로 나타나고 있으며, 기존의 "편한" 가정, 즉 유전자간 상관관계가 매우 약하며, 따라서 유전자간 유사 독립성을 가정할 수 있다는 주장이 비현실적이라는 것을 보고하고 있다. Qui 등 (2005b)은 각 유전자의 검정통계량을 병합하여 통계적 추론을 하는 이른바 비모수적 경험적 베이즈 방법을 적용하면 검색된 특이발현 유전자수의 분산이 커진다는 것을 보고하고 있고, 이러한 분산의 불안전성 이유로서 유전자간 강한 상관관계를 지적하고 있다. 또한 Klebanov와 Yakovlev (2007)는 유전자간 상관관계가 통계적 분석을 어렵게 하는 요인이라기 보다는 유용한 정보의 원천이고 적정한 변환을 통하여 근사 독립을 유지할 수 있는 급수를 만들 수 있으며 이 급수를 ${\delta}$-급수라고 불렀다. 본 보고에서는 국내에서 생산된 2조의 cDNA 마이크로어레이 자료에서 유전자간 상관관계가 비교적 강하며, 장범위(長範圍)로 나타나는 것을 확인하며, 유사 독립성을 전제할 수 있는 ${\delta}$-급수가 cDNA 마이크로어레이에서도 발견되는 것을 보고하고자 한다, 동 보고는 추후 cDNA 마이크로어레이 자료의 분석에서도 유전자간 상관관계를 고려하여야 함을 강조하고 있다.

중학생의 학업스트레스와 학업동기유형 및 수학 학습 동기의 관계 분석 (Relationships among Academic Stress, Academic Motivation Types and Mathematics Learning Motivation of Middle School Students)

  • 김부미
    • 대한수학교육학회지:학교수학
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    • 제16권1호
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    • pp.157-180
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    • 2014
  • 본 연구에서는 중학생의 학업스트레스와 수학 학습 동기의 관계를 분석하고, 이를 바탕으로 중학생들의 학업동기유형이 학업스트레스와 매개하여 수학 학습 동기에 어떠한 영향을 미치는지를 구조모형분석을 통해 확인하였다. 상관분석 결과, 학업스트레스는 수학 학습 동기와는 부적 상관을 보였고, 학업동기유형 중 무동기와 통제동기와는 정적 상관을, 자율동기와는 부적 상관을 보였다. 또한 수학 학습 동기는 무동기와 통제동기와는 각각 부적 상관을, 자율동기와는 정적 상관을 보였다. 그러나 성취수준별 상관분석 결과, 수학 학습 동기와 통제동기는 상집단에서만 부적 상관을 보였고 하집단에서는 상관이 유의하지 않았다. 구조모형분석 결과, 중학생들의 학업스트레스와 수학 학습 동기는 학업동기유형에 의해 완전매개되는 것으로 나타났다. 이때 성취수준 상집단, 하집단, 남학생 집단, 여학생 집단 모두에서 학업동기유형 중 통제 동기는 수학 학습 동기에 영향을 미치지 않는 것으로 나타났다. 또한 학업스트레스가 학업동기유형을 매개하여 수학 학습 동기에 미치는 영향은 성취수준 상, 하 집단, 남녀 학생 집단에서 설명력의 차이가 나타났다. 성취수준 상집단에서 하집단보다 학업스트레스가 모든 학업동기유형을 더 많이 설명하는 것으로 나타났고, 하집단은 상집단보다 학업스트레스와 학업동기유형이 수학 학습 동기를 더 많이 설명하는 것으로 나타났다. 남학생보다 여학생 집단에서 학업스트레스가 무동기와 자율동기를 더 많이 설명하고, 학업스트레스와 학업동기유형이 수학 학습 동기를 설명하는 정도도 더 큰 것으로 나타났다.

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