• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.4 no.3
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• pp.217-224
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• 2011

This paper proposes DDPT(Dynamic Data Protection Technique) which solves the problem of private information exposure occurring in a dynamic database environment. The DDPT in this paper generates the MAG(Multi-Attribute Generalization) rules using multi-attributes generalization algorithm, and the EC(equivalence class) satisfying the k-anonymity according to the MAG rules. Whenever data is changed, it reconstructs the EC according to the MAC rules, and protects the identification exposure which is caused by the EC change. Also, it measures the information loss rates of the EC which satisfies the ${\ell}$-diversity. It keeps data accuracy by selecting the EC which is less than critical value and enhances private information protection.

• Journal of Communications and Networks
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• v.12 no.4
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• pp.358-365
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• 2010

We develop a low complexity cooperative diversity protocol for low energy adaptive clustering hierarchy (LEACH) based wireless sensor networks. A cross layer approach is used to obtain spatial diversity in the physical layer. In this paper, a simple modification in clustering algorithm of the LEACH protocol is proposed to exploit virtual multiple-input multiple-output (MIMO) based user cooperation. In lieu of selecting a single cluster-head at network layer, we proposed M cluster-heads in each cluster to obtain a diversity order of M in long distance communication. Due to the broadcast nature of wireless transmission, cluster-heads are able to receive data from sensor nodes at the same time. This fact ensures the synchronization required to implement a virtual MIMO based space time block code (STBC) in cluster-head to sink node transmission. An analytical method to evaluate the energy consumption based on BER curve is presented. Analysis and simulation results show that proposed cooperative LEACH protocol can save a huge amount of energy over LEACH protocol with same data rate, bit error rate, delay and bandwidth requirements. Moreover, this proposal can achieve higher order diversity with improved spectral efficiency compared to other virtual MIMO based protocols.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2002.11a
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• pp.31-35
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• 2002

본 논문에서는 DVB-T 표준안의 모든 동작모드를 지원하며 임펄스 잡음 제거, 안테나 diversity 수신, 향상된 채널추정방법을 적용한 유럽향 디지털 TV 수신용 채널 칩셋의 설계에 관한 내용이다. 설계된 칩은 여러 개의 구성 블럭으로 구성되어있는데 여기에는 여러 가지의 향상된 알고리즘과 설계 아키텍쳐가 사용되었다. 가정용 가전기기들이 발생시키는 일정주기의 임펄스 잡음을 제거하기 위하여 임펄스 잡음 제거 블록을 AGC뒤에 사용하였다. 동기부는 대략적 주파수동기, 미세 주파수동기, 대략적 타이밍동기, 미세 타이밍 동기 등으로 이루어져 있으며 본 설계의 주파수 보상 영역은 $\pm$280Khz, 타이밍 보상 영역은 $\pm$500ppm이다. 파일럿 신호를 이용하여 채널추정과 보상을 수행하며 기존의 선형 보간기법과 함께 4개의 파일럿 신호를 이용한 보간기법을 사용하여 이동수신환경에 대응할 수 있도록 하였다. 이와 함에 수신성능을 개선할 수 있다고 알려진 안테나 diversity 기능을 채용하여 고정 및 이동 수신시의 수신성능을 향상시켰다. 안테나 diversity를 위해서 2개 이상의 수신 칩이 사용되며 이를 위해서 본 설계에서는 MRC(Maximum Ratio Combining)알고리즘을 사용하였다 본 설계는 5층 메탈 0.18um 공정을 사용하였으며 2.7Mbit 의 메모리 소자를 포함하여 대략 300 만 게이트의 회로크기를 갖으며 100 핀 PQFP로 제작되었다. 본 논문에서는 설계된 회로의 각 블록별 기능에 대한 설명과 함께 시뮬레이션 결과와 ASIC설계결과를 기술하였다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.4
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• pp.34-40
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• 2012

In wireless communication system, fading is an unavoidable problem. Hence, errors in form of BER are introduced with the transmitted signal. It is necessary to recognize the behavior of these errors in different fading channels. To obtain the mathematical solution for the average bit error rate(BER) of coherent MPSK, some techniques are presented. In this paper, the impact of diversity is also analyzed over slow and flat Rician fading channel. In here, the value of modulation index, M is varied and the effects of its variation are also depicted. So, these performance curves with different diversity values and fading parameter are useful to design and evaluate the radio channel for faithful communication system.

• Molecules and Cells
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• v.27 no.2
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• pp.225-235
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• 2009

Antibody phage display provides a powerful and efficient tool for the discovery and development of monoclonal antibodies for therapeutic and other applications. Antibody clones from synthetic libraries with optimized design features have several distinct advantages that include high stability, high levels of expression, and ease of downstream optimization and engineering. In this study, a fully synthetic human scFv library with six diversified CDRs was constructed by polymerase chain reaction assembly of overlapping oligonucleotides. In order to maximize the functional diversity of the library, a ${\beta}$-lactamase selection strategy was employed in which the assembled scFv gene repertoire was fused to the 5'-end of the ${\beta}$-lactamase gene, and in-frame scFv clones were enriched by carbenicillin selection. A final library with an estimated total diversity of $7.6{\times}10^9$, greater than 70% functional diversity, and diversification of all six CDRs was obtained after insertion of fully randomized CDR-H3 sequences into this proofread repertoire. The performance of the library was validated using a number of target antigens, against which multiple unique scFv sequences with dissociation constants in the nanomolar range were isolated.

• Journal of Distribution Science
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• v.19 no.11
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• pp.17-25
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• 2021

Purpose: This study aims to examine the effect of gender diversity and institutional ownership on earnings management in distribution industry sub-sector companies listed on the Indonesia Stock Exchange in 2017-2018. Research design, data and methodology: This research is case study research, where the population in this study are all distribution sub-sector companies listed on the IDX in 2017-2018. The sample selection technique used was purposive sampling and obtained 74 companies with the 2017-2018 research period. Multiple linear regression analysis was used in this study, using Stata 17. Results: The results of this study indicate that: 1) Gender diversity has a negative effect on earnings management. 2) Institutional ownership has a negative effect on earnings management. Conclusions: This study contributes to the agency theory where gender diversity and institutional ownership can reduce the agency conflict that the shrinkage of earnings management. These results indicate that companies in which there are female directors will reduce earnings management practices, this is due to the attitude of female directors who tend to avoid risk. The results also show that institutional ownership will also lead to reduced levels of earnings management, because institutional investors will increase its oversight of the company.

• Asia-Pacific Journal of Business
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• v.12 no.4
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• pp.211-225
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• 2021

Purpose - This study deals with the Openness to Diversity(OD) of soldiers in the military organization for efficient unit operation of the military organization composed of various soldier. The purpose of this study was to examine the effects of information and value OD on innovative behavior and the mediating effect of unit-members trust. Design/methodology/approach - The 269 samples of this study were surveyed on army soldiers. The Exploratory Factor Analysis (EFA), the multiple regression, bootstraping analysis were hired in order to analyze the data. Findings - The results showed that the information & value OD were positive(+) effect on innovative behavior. Unit-members trust showed a mediation effect between OD and innovative behavior. Research implications or Originality - First, according to Defense Reform 2.0, the military is expected to be composed of more diverse classes in the future. There is a theoretical contribution that examine their perception of diversity within the military. Second, OD was confirmed as a variable predicting the innovative behavior of soldiers and unit-memeber trust mediate the relationship between OD and invative behavior.

• Educational Technology International
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• v.14 no.1
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• pp.55-74
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• 2013

The diversity of students is getting increased in the contemporary classroom. To deal with the diversity, differentiated instruction (DI) should be considered as a way of providing alternative approaches to content, process and product according to the students' readiness, interest, and learning needs. Teachers have problems and difficulties in supporting different student's needs. In fact, teachers need proven tools including framework, guidelines or computing systems to help to practice DI in real context. According to the activity theory, tools influence on how people act and think and even their social practice, playing a crucial role in mediating the activities with people. In DI practice, there are also some studies about physical and abstract tools, but they have been not widely utilized by teachers in real schools. It means that more innovative tool to promote DI might be required. Therefore, to design a better tool to mediate the DI activities with teacher, case studies were conducted. In order to elicit the design implications, two physical and two abstract tools for DI practice were analyzed as case studies. Through the analysis of the case studies, eight design implications better to facilitate DI practice were suggested. This study has implications in suggesting design guidelines for teachers' tools to facilitate their DI practice by analyzing case studies in DI practices for an innovative tool in the educational practice.

• Korean Architects
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• s.587
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• pp.136-143
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• 2018

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.3
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• pp.40-45
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• 2008

This paper proposes the signal design techniques of quasi-orthogonal space time block codes (QO-STBCS) on the multi-dimensional signal space. In the multiple antenna system(MIMO), QO-STBC achieves the full-diversity and full-rate by grouping two based-symbols. We study the condition for the full-diversity of the grouping QO-STBC geometrically and the performance analysis of codes on the multi-dimensional signal space regarding the various signal constellations. Simulation results show that the way of the performance analysis is validity.