• Title/Summary/Keyword: Relational

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Incremental Maintenance of Horizontal Views Using a PIVOT Operation and a Differential File in Relational DBMSs (관계형 데이터베이스에서 PIVOT 연산과 차등 파일을 이용한 수평 뷰의 점진적인 관리)

  • Shin, Sung-Hyun;Kim, Jin-Ho;Moon, Yang-Sae;Kim, Sang-Wook
    • The KIPS Transactions:PartD
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    • v.16D no.4
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    • pp.463-474
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    • 2009
  • To analyze multidimensional data conveniently and efficiently, OLAP (On-Line Analytical Processing) systems or e-business are widely using views in a horizontal form to represent measurement values over multiple dimensions. These views can be stored as materialized views derived from several sources in order to support accesses to the integrated data. The horizontal views can provide effective accesses to complex queries of OLAP or e-business. However, we have a problem of occurring maintenance of the horizontal views since data sources are distributed over remote sites. We need a method that propagates the changes of source tables to the corresponding horizontal views. In this paper, we address incremental maintenance of horizontal views that makes it possible to reflect the changes of source tables efficiently. We first propose an overall framework that processes queries over horizontal views transformed from source tables in a vertical form. Under the proposed framework, we propagate the change of vertical tables to the corresponding horizontal views. In order to execute this view maintenance process efficiently, we keep every change of vertical tables in a differential file and then modify the horizontal views with the differential file. Because the differential file is represented as a vertical form, its tuples should be converted to those in a horizontal form to apply them to the out-of-date horizontal view. With this mechanism, horizontal views can be efficiently refreshed with the changes in a differential file without accessing source tables. Experimental results show that the proposed method improves average performance by 1.2$\sim$5.0 times over the existing methods.

An Interconnection Method for Streaming Framework and Multimedia Database (스트리밍 프레임워크와 멀티미디어 데이타베이스와의 연동기법)

  • Lee, Jae-Wook;Lee, Sung-Young;Lee, Jong-Won
    • Journal of KIISE:Software and Applications
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    • v.29 no.7
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    • pp.436-449
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    • 2002
  • This paper describes on our experience of developing the Database Connector as an interconnection method between multimedia database, and the streaming framework. It is possible to support diverse and mature multimedia database services such as retrieval and join operation during the streaming if an interconnection method is provided in between streaming system and multimedia databases. The currently available interconnection schemes, however have mainly used the file systems or the relational databases that are Implemented with separated form of meta data, which deafs with information of multimedia contents, and streaming data which deals with multimedia data itself. Consequently, existing interconnection mechanisms could not come up with many virtues of multimedia database services during the streaming operation. In order to resolve these drawbacks, we propose a novel scheme for an interconnection between streaming framework and multimedia database, called the Inter-Process Communication (IPC) based Database connector, under the assumption that two systems are located in a same host. We define four transaction primitives; Read, Write, Find, Play, as well as define the interface for transactions that are implemented based on the plug-in, which in consequence can extend to other multimedia databases that will come for some later years. Our simulation study show that performance of the proposed IPC based interconnection scheme is not much far behind compared with that of file systems.

Inequalities in Self-rated Health among Middle-aged and Young-old Waged Workers: The Contribution of Precarious Employment and Social Capital (중고령기에서 초기노년기에 걸친 주관적 건강상태의 격차: 고용형태와 사회적 자본의 효과를 중심으로)

  • Ahn, Joonhee
    • 한국노년학
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    • v.37 no.3
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    • pp.727-745
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    • 2017
  • This study purported to examine the effects of precarious employment and social capital on the changes of self-rated health status among the middle aged and the young-old population in South Korea. The study analyzed 12 year follow-up data generated by the Korean Labor and Income Panel Study(KLIPS 6-17), which included 10532 employed subjects aged 55 to 75. Multi-level growth curve modeling was performed by fixed and random effect models using STATA 13.0 program. Afterwards, Hausman test was performed, which resulted in support of the estimation by fixed effect model. The results showed that a day labor position was significant factor affecting the deteriorated changes of self-rated health status over time. In addition, wage, weekly working hours, and private/relational social capitals were also found to be significant factors affecting the changes of the self-rated health status. The results supported the divergence hypothesis as well as the cumulative advantage theory. Efforts should be made to develop and implement various employment support policies and social service programs to alleviate the health inequality of the employed workers over their middle-aged to young-old period.

A study on the use of fire hydrants as a heat wave reduction facility through hydraulic analysis of water supply network (상수관망 수리해석을 통한 폭염 저감 시설로써의 소화전 활용방안연구)

  • Hong, Sung Jin;Choi, Doo Yong;Yoo, Do Guen
    • Journal of Korea Water Resources Association
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    • v.54 no.12
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    • pp.1215-1222
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    • 2021
  • In this study, a study on how to use a fire hydrant as a heat wave reduction facility through hydraulic analysis of the water supply pipe network was conducted. Assuming that the fire hydrant installation point is open for heat wave reduction, the water pressure at each point was derived. And the reduction rate of the temperature according to the hydrant watering was compared with the watering area according to the operation of the watering truck. The watering area according to the opening of the fire hydrant was calculated by deriving the pressure value at the node where the fire hydrant was installed through hydraulic analysis of the water pipe network, and then using the watering radius relational expression according to the pressure value. As a result of applying the proposed methodology to two real city areas, the temperature reduction effect of the watering method by a fire hydrant can be derived lower than the watering method by a watering truck according to the difference in the absolute watering area. However, unlike a watering truck, a fire hydrant does not have a relative restriction on the amount of water supply and is expected to allows continuous divided spraying of the same area.

Exploring Science Teacher Agency at the Age of the New Normal after the COVID-19 Pandemic: The Case of Second Year of Distance Learning Practice (코로나 뉴노멀 시대의 과학교사 행위주체성 탐색 -COVID-19에 따른 원격 수업 2년 차 실행 사례를 중심으로-)

  • Lee, Hyekeoung;Kim, Heui-Baik
    • Journal of The Korean Association For Science Education
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    • v.41 no.5
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    • pp.415-428
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    • 2021
  • The COVID-19 pandemic has changed everything, even education. Last year when distance learning was introduced, science teachers faced many challenges to overcome. However, teachers adapted quickly, and in this year, it became the 'new normal'. In this situation, teachers are likely to habitually repeat past practices, but the context of the second year of distance learning is changing constantly, and teachers are asked to interpret the problem occurring in a situation and to adjust their practice for solving the problem with their teacher agency. In this study, we explore the emergence of science teacher agency and factors shaping teacher agency in the second year of distance learning and we focus on teachers' agentic practice that did not follow their past practice without reflection. For this purpose, we mainly analyze the semi-constructed interview of three science teachers. In the first year of distance learning, two teachers maintained their practice, not much different to face-to-face learning. However, one teacher reflected upon herself and started to recognize and solve her problems. Reflection for her practice can support this process. Another teacher changed her practice due to external suggestions, but it evolved her practice to fit the situation better, and her experience of last year helped her to adapt to the change. The other teacher who modified her practice to persist her professional purpose last year was consistently practicing in the second year and collaboration and autonomy can support her. This study shows the teachers' dynamic change of agency and the emergence for the relational interaction between teacher and context.

The Effect of Salesperson's Guanxi on Sale Performance : A Comparison with Customer Orientation

  • Lee, Sang-Jin;Song, Shan-Ji;Chang, Woo-Choul;Kim, Kun-Bae
    • International Journal of Advanced Culture Technology
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    • v.9 no.3
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    • pp.92-99
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    • 2021
  • In this research, it was investigated the competence of Korean salesmen in the insurance business(B2C, consumer goods marketing) and information communication industry(B2B, industrial goods marketing) at the individual level rather than the organizational level. The salesperson's Guanxi ability means the salesperson's ability to create, maintain, develop the Guanxi ability. Namely, it was investigated whether the Korean salesman's Guanxi ability is the effective and persuasive concept in explaining the sales performance(company performance, business performance). The purpose of this paper was to verify which variables, among Guanxi ability and customer orientation, better explain the sales performance of salespeople. The Western concept of marketing that is closest to Guanxi is the concept of the customer-orientation that is based on the theory of relationship exchange. Confucian culture in the East is the construct concept, Guanxi is the measurement. The relational exchange theory in the West is the construct concept, customer orientation is the measurement. As the result of the analysis, we found that the Guanxi proved a greater correlation with sales performance than customer orientation. In the information technology industry, there was a big difference compared to insurance industry, whereas Guanxi and customer orientation had a similar level of correlation with sales performance. In the case of the insurance industry, we found that the Guanxi and sales performance were significant but the customer orientation and sales performance were not. This means that sales performance can be accurately and sufficiently explained only by adding the Guanxi ability in addition to customer orientation. The result of analyzing the mediating effect of the Guanxi ability between customer orientation and company performance, customer orientation was significant with Guanxi, and customer orientation and company performance were also significant. But, when the Guanxi was used as the parameter, the Guanxi was significant with company performance, but the customer orientation was not. Even when the dependent variable was business performance, when the Guanxi was used as the parameter, we found that the Guanxi was significant with the business performance, but the customer orientation was not. Namely, it proved Guanxi ability and customer orientation are completely independent concepts. In addition, we found that the information technology industry, unlike the insurance industry, mediated the Guanxi ability between customer orientation and sales performance. We confirmed that in the future, salespeople should not only rely on rational methods to maintain and reinforce customer relationships, but must consider the emotional factors through empathy with customers.

The Conceptualization of Caring Justice and an Evaluation of Long-Term Care Policy in Korea (돌봄정의(Caring Justice) 개념구성과 한국 장기요양정책의 평가)

  • Seok, Jae-Eun
    • 한국사회정책
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    • v.25 no.2
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    • pp.57-91
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    • 2018
  • Despite the rapid growth of social care, understanding of care is segmental and caring is still marginalizing. The socialization of caring is actually a 'half-socialization' that is the result of injustice surrounding caring. Therefore, it is necessary to approach the problem of caring in terms of justice. In this paper, I discuss the limitations of social justice based on John Rawls 's social contract theory in the discussion of caring justice through feminists'writings on caring ethics. And then applying Nancy Fraser' s three scales of Justice-redistribution, recognition, and representation, the concept of caring justice has been newly constructed. The concept of caring is defined as a unified concept of caring including the aspect of the social rights of the care recipient as well as the labor rights of the care provider. Based on the analysis of care justice, we derive the ideal types of care policy and then evaluate the long-term care policy for the elderly, which is the central axis of Korean care policy. The results of this study are as follows: First, it is necessary to strengthen the labor rights of care providers especially for the socialization of care responsibilities and the proper allocation of social resources. Second, a service delivery system and care culture are needed to ensure the relational autonomy of care-receivers and care-givers for caring ethics and individualization of care. Third, the issue of care should be treated as the central agenda of politics in order to distribute care responsibility democratically and to distribute legitimate resources. This requires a paradigm shift from marginalization of care to mainstreaming of care. Ultimately, we should aim for a Caring Society.

Smart phone dependence Intervention Program meta-analysis for elementary school students (스마트폰 중독 초등학생을 위한 개입프로그램 메타분석)

  • Zheng, Song-Hua;Lee, Keung-Eun;Kim, Mi-Jung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.2
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    • pp.144-152
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    • 2019
  • Reckless use of the Internet by children is a barrier to daily life and has a negative impact on children's physical, psychological and relational aspects. But more and more children depend on the Internet. Thus, the study conducted a meta-analysis to examine the effectiveness of group programs that involve Internet addiction among elementary school students. The study analyzed 18 studies of a local Internet group counseling program. First, the overall effectiveness of Internet-dependent group programs that cause Internet addiction reduction in elementary school students is shown to be g=0.90, indicating that group counseling programs are effective in reducing Internet addiction and changing related variables. Second, as a result of verifying differences between groups, there were differences in effectiveness in voluntary participation motivations. Therefore, intervention by elementary school students requires preventive training for smart phones so that voluntary participation can occur, and education for parents to develop autonomy for children to use smartphones properly. And rather than making these efforts limited to smart phones, IT retriever education needs to be organized.

A Systematic Review on Sex Education of Children and Adolescent With Developmental Disabilities (발달장애를 가진 아동·청소년의 성교육 연구에 대한 체계적 고찰)

  • Cho, Hye-jin;Lee, Hye-kyung;Choi, Jeong-sil
    • The Journal of Korean Academy of Sensory Integration
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    • v.16 no.3
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    • pp.50-65
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    • 2018
  • Objective : The purpose of this study is to analyze researches about sex education for children and adolescents with developmental disabilities in order to provide a basic data and a direction about sex education. Methods : For the systemic review, domestic and international research articles published from August 2008 to September 2018 were searched using the electronic databases PubMed, EBSCO host (CINAHL Plus with full text), Medline (ProQuest), RISS, and KISS. Keyword used for the search was 'Disability Disorder OR Autism (AND) AND (Effect OR Effectiveness)' for international papers and 'Disability AND Sex Education' for domestic papers. Total 15 articles were collected and analyzed in terms of participant, duration, type, contents, and teaching methods with PICO format. Results : In terms of level of evidence, majority was Level III evidence(60%). Most common contents of sex education were 'physical and growth' and 'relational skills'. Special education and occupational therapy were the field that sex education is provided most frequently. Effects of sex education identified were 'sex knowledge', 'sex attitudes', and 'inappropriate sexual behavior'. Conclusion : This study intend aimed to identify content, trends, and effects of sex education for children and adolescents with developmental disabilities in order to provide a basic data for clinical trial of sex education in occupational therapy practice. This study recommend further researches on the effects of sex education on occupational participation, occupational therapists' awareness of sexual activity of clients, and development of related measurement such as sexual development scale.

Domestic Research Trends and Cases of University Education and Operation in the Era of the Fourth Industrial Revolution (제4차 산업혁명 시대에서의 대학 교육 및 운영에 관한 연구 동향과 사례)

  • Kim, Kyu Tae
    • Journal of Digital Convergence
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    • v.17 no.8
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    • pp.15-26
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    • 2019
  • This study was to explore the domestic research trends, and education and operation cases concerned with Korean colleges in the fourth industrial revolution era. It was conducted through the analysis of 114 academic papers registered to the Korea Research Foundation, the newspaper articles, and the main 4-year university homepage from 2016 to April 2019. The results was as follows. Research papers have been increasing since 2016; research were conducted by humanities and social sciences as well as engineering academics interesting in research topics such as technologies, curriculum, and teaching and learning by mainly using quantitative research, literature research. As for the college education, reorganization of the undergraduate and majors centered on the science and engineering field, teaching and learning related with learner's participation and performance, and provide efficient academic affairs management and career guidance using Chatbot or Cloud computing. Industry-academia cooperation was focuses on the field of science and engineering. In future research, it is necessary to explore the research on college students' career and employment, the research on academic affairs management and infrastructure, the relational research considering the variables among college students and faculties, and the qualitative and mixed method approach.