• Title/Summary/Keyword: Cross-sectional Comparative Study

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Characterization of Cu-Ni alloy thin films deposited by magnetron co-sputtering as a function of target configurations (마그네트론 코-스퍼터링에 의한 구리-니켈 합금박막 증착시 타겟의 구성방법에 따른 물성 분석)

  • SEO, Soo-Hyung;LEE, Jae-Yup;PARK, Chang-Kyun;PARK, Jin-Seok
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1485-1487
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    • 2000
  • A variety of target configurations in sputtering process have been proposed to deposit various structures of thin film alloys and compound films. In this study, we presented the comparative experimental results regarding to the characterization of properties of Cu-Ni thin films deposited by using a magnetron co-sputtering method, as a function of target configurations; one is using a single target with varying the area of Ni chips attached on the Cu target and another is using a dual-type target with two targets of Ni and Cu separated each other. Structural(d-spacing, crystal orientation, crystallite size, cross-sectional morphology) and electrical(resistivity) properties of deposited films are characterized and compared as a function of target configurations as well as deposition conditions.

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고효율 LED 제작을 위한 비,반극성 GaN의 성장 및 결함 분석

  • Gong, Bo-Hyeon;Kim, Dong-Chan;Kim, Yeong-Lee;An, Cheol-Hyeon;Bae, Yeong-Suk;U, Chang-Ho;Seo, Dong-Gyu;Nam, Ok-Hyeon;Yu, Geun-Ho;Jang, Jong-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.172-172
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    • 2009
  • In this study, we presented comparative discrimination methods to identify various line and planar defects observed in nonpolar a-GaN epilayers on r-sapphire substrates. Unlike the case of conventional c-GaN, which is dominated by perfect threading dislocations, systematic identification of undistinguishable defects using transmission electron microscopy (TEM) is necessary to suppress the propagation of defects in nonpolar GaN epilayers. Cross-sectional TEM images near the [0001] zone axis revealed that perfect mixed and pure screw type dislocations are visible, while pure edge, partial dislocations, and basal stacking faults (BSFs) are not discernible. In tilted cross-sectional TEM images along the [$1\bar{2}10$] zone axis, the dominant defects were BSFs and partial dislocations for the $g=10\bar{1}0$ and 0002 two-beam images, respectively. From plan view TEM images taken along the [$11\bar{2}0$] axis, it was found that the dominantpartial and perfect dislocations were Frank-Shockley with b=${\pm}1/6$<$20\bar{2}3$> and mixed type without an 1 component including b=${\pm}1/3$<$1\bar{2}10$> and ${\pm}1/3$<$\bar{2}110$>, respectively. Prismatic stacking faults were observed as inclined line contrast near the [0001] zone axis and were visible as band contrast in the two-beam images along the [$1\bar{2}10$] and [$11\bar{2}0$] zone axes.

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Association between the Angiotensin-converting Enzyme Gene Insertion/Deletion Polymorphism and Essential Hypertension in Young Pakistani Patients

  • Ismail, Muhammad;Akhtar, Naveed;Nasir, Muhammad;Firasat, Sadaf;Ayub, Qasim;Khaliq, Shagufta
    • BMB Reports
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    • v.37 no.5
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    • pp.552-555
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    • 2004
  • Several studies have demonstrated the importance of angiotensin-converting enzyme (ACE) insertion (I)/deletion (D) polymorphisms in the pathogenesis of hypertension. This study sought to determine the association between the ACE I/D polymorphism and essential hypertension in young Pakistanis. The frequency of the ACE I/D polymorphism was established by a comparative cross-sectional survey of Pakistani patients suffering from essential hypertension and ethnically matched normotensive controls. Samples were collected from tertiary care hospitals in northern Pakistan. Hypertensive individuals were defined as those with a systolic blood pressure > 140 mmHg and/or diastolic blood pressure > 90 mmHg on three separate occasions, or those currently receiving one, or more, anti-hypertensive agents. DNA samples obtained from hypertensive (n=211) and normotensive (n=108) individuals were typed by PCR. The frequency of the ACE I/I genotype was significantly higher in hypertensive patients, aged 20-40 years, than in normotensive controls of the same age group ($\chi^2$ = 4.0, P = 0.041). Whereas no overall significant differences were observed between the I/I, I/D and D/D ACE genotypes (One way ANOVA, F=0.672; P=0.413). The association between the ACE I/I genotype and essential hypertension in individuals aged $\leq$ 40 years suggests that ACE has a role in early onset essential hypertension in Pakistan.

Temporal Change in Vertical Distribution of Woody Vegetation on the Flank of Sakurajima Volcano, Southern Kyushu, Japan

  • Teramoto, Yukiyoshi;Shimokawa, Etsuro;Ezaki, Tsugio;Lim, Young-Hyup;Kim, Suk-Woo;Chun, Kun-Woo
    • Journal of Forest and Environmental Science
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    • v.32 no.3
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    • pp.270-279
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    • 2016
  • This study explained vertical distributions and growth environments for woody vegetation. It had been degenerated by long-term volcanic activity of Sakurajima; vegetation and thicknesses of tephra layers and forest soils were investigated at 5 sites (250-700 m in altitude) with different altitudes localized at the northwestern-northern flanks of Sakurajima in Kagoshima Prefecture. The results in 2015 were compared with the vertical distribution of woody vegetation in 1963, when the volcanic activity of Sakurajima was relatively moderate. Thus, we investigated temporal changes in the vertical distribution of woody vegetation owing to volcanic activity over about 50 years (1963-2015). We indicated altitude decreased, the number of woody vegetation, number of species, sum of cross-sectional area of tree diameter at breast height, Fisher-Williams's diversity index ${\alpha}$, and forest soil thickness increased. However, these values were found to be degenerated when compared to climax forest values, and succession was incomplete. It seems that because the woody vegetation of the flank was affected by volcanic activity for a long time, exposing them to severe growth environments, areas with lower altitudes became distant from the craters of Sakurajima, thereby weakening the effect of volcanic activity in these areas at lower altitudes. a at the same altitudes over about 50 years (1963-2015) decreased by about 31-72%, and the sum of the cross-sectional area in tree diameter at breast heights decreased by about 14-62%. Thus, comparative growth environments for woody vegetation in 2015 were more severe than that of 1963, with respect to tephra layer thickness. In addition, for vegetation succession in the flank of Sakurajima, vegetation restoration should be promoted through the introduction of artificial woody plants covered by symbiotic microorganisms or organic materials.

Comparative Study of Approximate Optimization Techniques in CAE-Based Structural Design (구조 최적설계를 위한 다양한 근사 최적화기법의 적용 및 비교에 관한 연구)

  • Song, Chang-Yong;Lee, Jong-Soo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.11
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    • pp.1603-1611
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    • 2010
  • The comparative study of regression-model-based approximate optimization techniques used in the strength design of an automotive knuckle component that will be under bump and brake loading conditions is carried out. The design problem is formulated such that the cross-sectional sizing variables are determined by minimizing the weight of the knuckle component that is subjected to stresses, deformations, and vibration frequency constraints. The techniques used in the comparative study are sequential approximate optimization (SAO), sequential two-point diagonal quadratic approximate optimization (STDQAO), and approximate optimization based on enhanced moving least squares method (MLSM), such as CF (constraint feasible)-MLSM and Post-MLSM. Commercial process integration and design optimization (PIDO) tools are utilized for the application of SAO and STDQAO. The enhanced MLSM-based approximate optimization techniques are newly developed to ensure constraint feasibility. The results of the approximate optimization techniques are compared with those of actual non-approximate optimization to evaluate their numerical performances.

An Assessment and Comparative Analysis of Culture and Tourism Festival Service Quality, Satisfaction and Revisit (Focusing on 2013-2014 Cheonan World Dance Festival) (문화관광축제 서비스품질과 만족 및 재방문 평가 비교분석 (2013-2014년 천안흥타령 춤 축제를 대상으로))

  • Lee, Je-Yong;Lee, Kwang-Ok
    • The Journal of the Korea Contents Association
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    • v.16 no.6
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    • pp.649-661
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    • 2016
  • It was intended to enhance the quality of festival and contribute as image of refined local festival by making an empirical and cross-sectional analysis of effect that the overall quality of service provided in the local festival had on users' satisfaction and revisit intention by using 2013-2014 two-year data for visitors who had enjoyed "Cheonan Heungtaryeong Dance Festival", best festival designated by Ministry of Culture, Sports and Tourism after 2012. The results of analyzing a difference for 2 years are as follows. 1) Among social quality factors, both cultural effect and image effect showed a significant difference with p=.001 and p=.004. 2) Among process quality factors, food and souvenir showed a significant difference with p=.27. 3) Among physical quality factors, both convenience in connection with the visitors' enjoying the festival and facility arrangement didn't show difference between groups with p=.130 and .408. Finally, in the item of whether the overall service quality of festival had an effect on visitor satisfaction and whether visitor satisfaction with festival had an effect on revisit intention, each of these had p=.000. So, it was shown that there was statistically significant difference. In other words, it is proved that the enhancement of service quality lead to high satisfaction, and this arouses revisit intention and produces word of mouth effect.

A Comparative Study on the Effects of GMFM and ICF Sub-item Function on the Sub-item Activity and Participation Restriction of the ICF (GMFM과 ICF의 하위영역 기능이 ICF의 하위영역 활동과 참여문제에 미치는 영향 비교)

  • Lee, Jin;Kim, Eun kyong;Chun, Hyelim
    • Journal of Korean Physical Therapy Science
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    • v.26 no.3
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    • pp.15-22
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    • 2019
  • Background: The purpose of this study is to explore the effect of the functions of GMFM and ICF-CY on the activities and participation of ICF-CY sub-items. Design: Cross-sectional study. Method: This study compared and analyzed 95 children with cerebral palsy [type of CP: spasticity 86 (90.5%), hypotonia 4 (4.2%), mixed 5 (5.3%); type of palsy: quadriplegia 13 (13.7%), diplegia 71 (74.7%), hemiplegia 11 (11.6%)] using sub-items of functions, activities and participation from GMFM and ICF-CY. Result: The results show that the activities and participation of ICF-CY (9 sub-items) have significant effect on the functions of GMFM and ICF-CY (8 sub-items) (p<0.05). Conclusion: It is intended to provide data to establish practical therapeutic goals and interventions for functions, activities and participation, which are sub-categories of ICF-CY in cerebral palsy.

Comparison of Anxiety, Depression, and Quality of Life between Organ Transplant Candidates and Recipients (장기이식 대기자와 수혜자의 불안, 우울 및 삶의 질 비교)

  • Cha, Ji-Eun;Yi, Myung-Sun
    • Korean Journal of Adult Nursing
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    • v.24 no.3
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    • pp.284-293
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    • 2012
  • Purpose: The aim of this study was to compare the levels of anxiety, depression, and quality of life (QOL) among kidney or liver transplant candidates and recipients. Methods: A cross-sectional descriptive design was utilized. The 160 subjects were recruited and assigned to three different conditions: awaiting transplant group; post-transplantation (TPL) group within less than one year of surgery; and post-TPL group with one year and no more than two years post surgery. The levels of anxiety and depression were measured by the Hospital Anxiety and Depression Scale. The level of quality of life was measured by the Medical Outcomes Study Short Form-36 version 2. Results: The anxiety score was significantly higher in the waiting group compared with the 1~2 years post TPL group. The depression score was significantly higher in the waiting group compared with the post TPL groups. The QOL was significantly lower in the waiting group compared with the post TPL groups. Conclusion: Our results show a high prevalence of anxiety and depression and a marked reduction in the QOL in transplant candidates compared to the recipients. This study indicates that the group waiting for transplants may have unmet needs during that time period. Health professionals should be encouraged to attend to the psychological distress of the transplant candidates in order to improve their quality of life.

The Comparative Study on Mother's Rearing Attitude and Communication among Mother and Student between Mobile Phone Addiction Group and Non-addiction Group: Middle School Students (휴대폰 중독군과 비중독군의 어머니의 양육태도와 의사소통 차이비교: 중학생을 대상으로)

  • You, Mee-Sook;Kwon, Mi-Kyung
    • Korean Parent-Child Health Journal
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    • v.14 no.2
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    • pp.76-83
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    • 2011
  • Purpose: The purpose of this study is to compare the mother's rearing attitude and communication between mobile phone addiction group and non-addiction group in middle school students. Methods: A cross-sectional descriptive study was performed with 574 students from 3 middle schools (1 boy school, 1 girl school, 1 coeducation school) at G-city in Gangwon Province. The data was collected from the 10th to 24th of July in 2010. Statistical analysis of the results was carried out by means, frequencies, chi-square, t-test and multiple regression with SPSS/WIN 18.0 program. Results: There were significant differences in mobile phone addiction group and non-addiction group in regard to sex, school year, grades, mother' age, purpose of mobile phone use, activity after school, phone bill per month. Also There were significant differences in mother's rearing attitude and mother's communication between two groups. Conclusion: Mobile phone addiction among students is not serious, however, possibility of becoming an addict still remains. This study suggests that we have to educate them about proper mobile phone use in advance to prevent them from becoming a mobile phone addict in early stage. Therefore, we need to develop an educational program to prevent mobile phone addiction.

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Blood glucose levels, insulin concentrations, and insulin resistance in healthy women and women with premenstrual syndrome: a comparative study

  • Zarei, Safar;Mosalanejad, Leili;Ghobadifar, Mohamed Amin
    • Clinical and Experimental Reproductive Medicine
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    • v.40 no.2
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    • pp.76-82
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    • 2013
  • Objective: To compare the blood glucose levels, insulin concentrations, and insulin resistance during the two phases of the menstrual cycle between healthy women and patients with premenstrual syndrome (PMS). Methods: From January of 2011 to the August of 2012, a descriptive cross-sectional study was performed among students in the School of Medicine of Jahrom University of Medical Sciences. We included 30 students with the most severe symptoms of PMS and 30 age frequency-matched healthy controls. We analyzed the serum concentrations of glucose, insulin, and insulin resistance by using the glucose oxidase method, radioimmunometric assay, and homeostasis model assessment of insulin resistance equation, respectively. Results: No significant differences between the demographic data of the control and PMS groups were observed. The mean concentrations of glucose of the two study groups were significantly different during the follicular and luteal phases (p=0.011 vs. p<0.0001, respectively). The amounts of homeostasis model assessment of insulin resistance of the two study groups were significantly different in the luteal phase (p=0.0005). Conclusion: The level of blood glucose and insulin resistance was lower during the two phases of the menstrual cycle of the PMS group than that of the controls.