• Title/Summary/Keyword: theoretical analyses

Search Result 838, Processing Time 0.028 seconds

CEMS Study of Ferrite Films M0.2Fe2.8O4 (M =Mn, Ni, Cu) (페라이트 박막 M0.2Fe2.8O4(M=Mn, Ni, Cu)의 Mössbauer 분광학적 연구)

  • Park, Jae Yun;Kim, Kwang Joo
    • Journal of the Korean Magnetics Society
    • /
    • v.24 no.2
    • /
    • pp.46-50
    • /
    • 2014
  • The crystallographic properties and cationic distribution of $M_{0.2}Fe_{2.8}O_4$ (M =Mn, Ni, Cu) and $Fe_3O_4$ thin films prepared by sol-gel method have been investigated by X-ray diffraction (XRD) and conversion electron M$\ddot{o}$ssbauer spectroscopy (CEMS). The ionic valence, preferred site, and hyperfine field of Fe ions of the ferrites could be obtained by analyzing the CEMS spectra. The $M_{0.2}Fe_{2.8}O_4$ films were found to maintain cubic spinel structure as in $Fe_3O_4$ with the lattice constant slightly decreased for Ni substitution and increased for Mn and Cu substitution from that of $Fe_3O_4$. Analyses on the CEMS data indicate that $Mn^{2+}$ and $Ni^{2+}$ ions substitute octahedral $Fe^{2+}$ sites mostly, while $Cu^{2+}$ ions substitute both the octahedral and tetrahedral sites. The observed intensity ratio $A_B/A_A$ of the CEMS subspectra of the samples exhibited difference from the theoretical value. It is interpreted as due to the effect of the M substitution for A and B on the Debye temperature of the site. The relative line-broadening of the B-site CEMS subspectra can be explained by the dispersion of magnetic hyperfine fields due to random distribution of M cations in the B sites.

Technological Governance Regarding Life-Sustaining Technologies: The Limitations of RRI and Bioethics ("한국의 연명의료정책과 기술 거버넌스: 사회에 책임지는 기술혁신(RRI)의 적용 한계와 생명윤리")

  • Lee, June-Seok
    • 한국과학기술학회:학술대회논문집
    • /
    • 2015.12a
    • /
    • pp.247-278
    • /
    • 2015
  • Recently, as DNR prevails more and more in Korea, discussions regarding meaningless medical life-sustaining-treatment (LST) intensified. Some of the Supreme Court decisions are even discussed in mass media, causing public debates. These cases tell us that, as life-sustaining medical technologies are highly developed, more sociological and policy-related analyses are needed on them. Firstly, this study will review 40 previous studies that analyze recent discussions in Korea about LST. Secondly, this study also shows that in bioethical and policy-related perspectives, governance about LST calls for a new implications regarding thanatoethics and thanatopolitics. In this new theoretical framework, death with dignity (DwD) can be understood as a process of giving back the thanatopower to the subject who chooses his way of ending based on his sound and free will. Thirdly, some of the new LST or resuscitation technologies such as automated external defibrillators (AED) are developed in RRI framework. However, if subjects themselves choose not to apply those technologies on them, as in the case of DNR (do not resuscitate) vows, meaning of developing such technologies are to be questioned. But currently such questions regarding the limitations of RRI are seldom asked. I argue that in order to properly apply RRI framework on existing technology, we also need to consider these points.

  • PDF

A Study of Inter-Korean Cooperation in Science and Technology (남북한 과학기술협력에 대한 연구: 통합적 시각에서)

  • Kwon Ki-Seok
    • Journal of Science and Technology Studies
    • /
    • v.3 no.2 s.6
    • /
    • pp.29-60
    • /
    • 2003
  • Inter-Korean Cooperation in Science and Technology will contribute to building the trust between S.K and N.K as a leading factor and cut down the cost of unification by diminishing the technology lag and the gap of economic level. This study has shown that we can increase the productivity of unified Korea Innovation system if we systematically analyse the present condition of the Inter-Korean Cooperation and promote Inter-Korean Cooperation. In this study, the author analyses the present condition of the Inter-Korean Cooperation with integrated framework of three aspects to clear up the policy of Inter-Korean Cooperation. First, in the national aspect, we make use of the notion of international cooperation and multilateral mechanism of an international organization. Thereafter, we make out the alternatives in the aspects of international relationship and legal and institutional view Second, in the unification aspect, we consider the Inter-Korean Cooperation by the notion of national innovation system. Thereafter, we make out the alternative in the aspect of a phase-dependent approach. Finally, in technology aspect, we consider the Inter-Korean Cooperation by the notion of technology gap, the framework of technology transfer, and technology dependency theory. As a conclusion, through this study, the author have tried to integrate the various theoretical backgrounds. As a result, the author could analyse the present condition of ter-Korean Cooperation in Science and Technology and team a good lesson from it; Therefore, we can use it as a means of evaluation on a cooperation program and prediction for the future status of cooperation.

  • PDF

The Effects of Grandmaternal Child Care on Intergenerational Contacts: Focusing on Long-Term Reciprocity Relationships (모(母)의 손자녀 돌봄이 성인자녀와의 접촉 수준에 미치는 영향 : 장기적 상호 관계를 중심으로)

  • Ha, Seok Cheol;Hong, Kyung-Zoon
    • Korean Journal of Social Welfare Studies
    • /
    • v.47 no.1
    • /
    • pp.261-290
    • /
    • 2016
  • The purpose of this study was to examine how previous grandmaternal child care affects contacts between older mothers and their adult children. This study especially focused on intergenerational long-term reciprocity relationships. In this study, data from the first wave (in 2006) to the forth wave (in 2012) of Korean Longitudinal Study of Ageing yielded a sample of 1,925 elderly mothers and 7,460 adult children. This study employed multi-level analyses considering hierarchical structures between the mothers and their adult children. In this study, past grandmaternal child care was measured by providing care behavior and unit of time for care. Intergenerational contacts was measured by frequency of face-to-face and non-face-to-face contacts. The results showed that adult children who previously received child care from their mothers were more likely to contact to their mothers. Additionally, the increasing amount of time for elderly mothers to provide care to their grandchildren led to more frequent contacts between elderly mothers and their adult children. The findings proved that grandmaternal child care was in important position in reciprocal relationships between elderly mothers and their adult children. Through these results, this study suggested theoretical, policy, and practical implications.

A Study on the Appropriateness as Organic Matters Indicator and the Distribution of Chemical Oxygen Demand and Total Organic Carbon in Masan Bay, Korea (마산만 해수 중 화학적산소요구량과 총유기탄소 분포 특성 및 유기물 지표로서의 적절성 검토)

  • PARK, MI-OK;LEE, YONG-WOO;CHO, SEONG-AH;KIM, HYE-MI;PARK, JUN-KUN;KIM, SUNG-GIL;KIM, SEONG-SOO;LEE, SUK MO
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.26 no.2
    • /
    • pp.82-95
    • /
    • 2021
  • We investigated the temporal and spatial distribution characteristics of chemical oxygen demand (COD) and total organic carbon (TOC) in all 13 locations of Masan Bay from February to November in 2015. The COD and TOC contents were high during the June-August period when the pollution load increased. In particular, the concentrations of COD and TOC were about twice as high in the surface water as in the bottom water. In spatial distribution, the COD and TOC concentrations at the inner bay were about twice as high as those of the outer bay in Masan Bay. As a result of estimating the oxidation efficiency of COD from the surface layer of Masan Bay in 2015 based on the theoretical oxygen demand (TOD), it was at the level of about 23%. Due to the low oxidation efficiency of COD, there is a risk that the organic matter in Masan Bay will be somewhat underestimated. Therefore, for quantitative analysis of organic matter, COD and TOC analyses need to be combined.

A Meta-analysis on the Variables related with Recovery among Persons with Mental Illness (정신장애인의 회복관련변인에 관한 메타분석)

  • Park, Jung-Im
    • The Journal of the Korea Contents Association
    • /
    • v.18 no.12
    • /
    • pp.535-546
    • /
    • 2018
  • This study conducted a meta-analysis to examine syntagmatically on the variables related with recovery among persons with mental illness in Korea. In order to do a meta-analysis, theses and dissertations published between 1999 and 2018 in Korea were reviewed systematically and a total of 24 including studies were selected. Using Comprehensive Meta Analysis (CMA) 3.0 software, this study calculated average effect size and moderator variables related with recovery among persons with mental illness. Results were as follows. First, this study identified a total of 16 variables related with recovery among persons with mental illness. Second, the results indicated that variables which showed large effect sizes included social support(r=.575), empowerment(r=.555), self-efficacy(r=.544), social skill(r=.500), relationship with social worker(r=.482), stigma(r=-.446), family support(r=.418). Third, variables with medium effect sizes included interpersonal relationship capacity (r=.391), agency service satisfaction(r=.366), insight(r=.373) and symptom(r=-.239). Fourth, variables with small effect sizes included work experience(r=.188). Fifth, moderator analyses were conducted utilizing characteristics of residence state (community or mental hospital). Moderator effects were identified in the social support and family support. Based on the findings, theoretical and clinical implications for the recovery among persons with mental illness in Korea were discussed.

The effectiveness of a flipped learning on Korean nursing students; A meta-analysis (국내 간호대학생에게 적용한 플립러닝의 효과에 대한 메타분석)

  • Kang, Mi-Jung;Kang, Kyung-Ja
    • Journal of Digital Convergence
    • /
    • v.19 no.1
    • /
    • pp.249-260
    • /
    • 2021
  • This study is a meta-analysis study conducted to integrate and analyze the results of flip-learning studies for Korean nursing students. We searched PubMed, EMBASE, Cochrane, CINAHL, and Korean databases. Randomized controlled trials (RCTs) and Non-Randomized controlled trials (Non-RCTs) evaluating the effects of flipped learning for Korean nursing students were included. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated using a random-effects meta-analysis. The entire effect size in flipped learning was big in effect size (SMD = 1.21; 95% CI = 0.84 to 1.63; I2 = 93.9; n = 23) compared to the control groups. The analysis results of subgroups according to the classification of Bloom showed that flipped learning was found to have a significant effect on psychomotor domain, cognitive domain, and affective domain. A total of 10 literature analyses, this meta-analysis showed that flipped learning on Korean nursing students is effective in psychomotor, cognitive, and affective domain than the traditional teaching method. The flip learning can be integrated into theoretical and practical nursing education to improve the academic performance of nursing students.

The Effects of Perceived Social Fairness and the Possibility of Upward Social Mobility on Emotional Depression (사회적 공정성에 대한 지각 및 계층상승 가능성에 대한 기대가 정서적 우울에 미치는 영향)

  • Roh, Minjung
    • The Journal of the Korea Contents Association
    • /
    • v.21 no.1
    • /
    • pp.173-184
    • /
    • 2021
  • This paper aims to examine the effects of perceived social fairness and upward social mobility on the individual emotional depression. Specifically, this study investigates the conditions under which the effects are more or less pronounced for the sake of shedding more light on the relationship between social-cognitive and psychological factors. The key proposition of this study is that as one holds more favorable beliefs about the fairness of the society to which (s)he belong, (s)he would have more optimistic expectations for the possibility of his or her own upward social mobility. Moreover, the decrease of this expectation could exacerbate his or her emotional depression with the expectation that (s)he might not get what (s)he deserves despite his or her time and effort put into achieving such goals. This study also adds further boundary conditions to these effects, such that the decrease of emotional depression is more pronounced when (1)social capital and (2)economic resources are scarce (versus abundant). To test these predictions, this study used the survey data on a total of 8000 people collected by Gallup Korea at the request of the Korea Institute of Public Administration. The analyses provided support for the proposed model of the present study. These results should contribute to laying the theoretical foundation for the establishment of policies and research models on the enhancement of fairness and prevention of depression in the future.

Studies on Derivation of Appropriate Geodetic System Transformation Schemes for Spatial Data (공간정보의 측지기준체계 변환 기법 도출에 관한 연구)

  • Yun, Seonghyeon;Lee, Hungkyu;Song, Jinhun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.38 no.6
    • /
    • pp.561-571
    • /
    • 2020
  • Seven techniques widely used in the geodetic transformations have been reviewed and compared to figure out their theoretical characteristics. A series of numerical tests were performed about four data sets. This was followed by result analyses in terms of transformation residuals and accuracies together with some hypothesis testings based on the student-t distribution to confirm the statistical significance of the techniques. In the case of the transformation between the geodetic frames implemented in the same system, no statistical significance was revealed in the results of the 3D transformation techniques, even if the testing area becomes large as the Asia-Oceania continent. Among the 2D transformations, it was possible for the NTv2 grid modeling technique to deliver improved transformation accuracy. Finally, it was possible from the results analyzed in this study to propose the Helmert transformation to geodetic control points and the NTv2 technique to the 2D spatial data transformation of the geodetic systems.

Exploration of Knowledge Hiding Research Trends Using Keyword Network Analysis (키워드 네트워크 분석을 활용한 지식은폐 연구동향 분석)

  • Joo, Jaehong;Song, Ji Hoon
    • Knowledge Management Research
    • /
    • v.22 no.1
    • /
    • pp.217-242
    • /
    • 2021
  • The purpose of this study is to examine the research trends in the filed of individual knowledge hiding through keyword network analysis. As individuals intentionally hide their knowledge beyond not sharing their knowledge in organizations and the research on knowledge hiding steadily spreads, it is necessary to examine the research trends regarding knowledge hiding behaviors. For keyword network analyses, we collected 346 kinds of 578 keywords from 120 articles associated with knowledge hiding behaviors. We also transformed the keywords to 86 nodes and 667 links by data standardizing criteria and finally analyzed the keyword network among them. Moreover, this study scrutinized knowledge hiding trends by comparing the conceptual model for knowledge hiding based on literature review and the network structure based on keyword network analysis. As results, first, the network centrality degree, knowledge sharing, creativity, and performance was higher than others in Degree, Betweenness, Closeness centrality. Second, this study analyzed ego networks about psychological ownership and individual emotion theoretically associated with knowledge hiding and explored the relationship between variables through comparing with the conceptual model for knowledge hiding. Finally, the study suggested theoretical and practical implications and provided the limitations and suggestions for future research based on study findings.