• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권6호
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• pp.2497-2517
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• 2020

For compressed sensing (CS) applications, it is significant to construct deterministic measurement matrices with good practical features, including good sensing performance, low memory cost, low computational complexity and easy hardware implementation. In this paper, a deterministic construction method of bipolar measurement matrices is presented based on binary sequence family (BSF). This method is of interest to be applied for sparse signal restore and image block CS. Coherence is an important tool to describe and compare the performance of various sensing matrices. Lower coherence implies higher reconstruction accuracy. The coherence of proposed measurement matrices is analyzed and derived to be smaller than the corresponding Gaussian and Bernoulli random matrices. Simulation experiments show that the proposed matrices outperform the corresponding Gaussian, Bernoulli, binary and chaotic bipolar matrices in reconstruction accuracy. Meanwhile, the proposed matrices can reduce the reconstruction time compared with their Gaussian counterpart. Moreover, the proposed matrices are very efficient for sensing performance, memory, complexity and hardware realization, which is beneficial to practical CS.

• Biomolecules & Therapeutics
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• 제20권5호
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• pp.446-456
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• 2012

Actoprotectors are preparations that enhance body stability against physical loads without increasing oxygen consumption or heat production. Or, in short, actoprotectors are synthetic adaptogens with a significant capacity to improve physical performance. This paper explores the history of actoprotectors' development, their pharmacological properties, mechanism of action, and practical application to the improvement of mental and physical performance. A brief summary of the clinico-pharmacological characteristics of the main representatives of this class (bemitil and bromantane) is provided. Some other synthesized compounds, and even natural ones such as ginseng, also are regarded as potential actoprotectors, and these are treated herein as well. Actoprotectors, owing to their wide-ranging pharmacological activities, high efficiency and safety, can be applied under either normal or extreme conditions.

• 대한전기학회논문지
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• 제38권11호
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• pp.877-887
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• 1989

In this paper, we attempt to achieve high dynamic performance by means of decoupled control of rotor speed and flux. Recently developed nonlinear feedback control theories are utilized. The rotor fluxes are estimated based on the rotor circuit equations. When the estimation error of the rotor flux tends to zero, the rotor speed and flux dynamic characteristics of the induction motor with our controller become linear. To minimize the deterioration of control performance, we use an identification algorithm for the rotor resistance. We analyze the dynamic behavior of the closed loop system with our controller. Both simulation and experimental results are included to demonstrate the practical significance of our result. In particular, our experimental results show that recently developed nonlinear feedback control techniques are of practical use in control of induction motors.

• 한국정보과학회논문지:시스템및이론
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• 제34권5_6호
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• pp.169-175
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• 2007

써픽스 배열은 기본적인 전체 텍스트 인덱스 자료구조로서, 반복되는 패턴 질의 수행 시 효율적으로 사용될 수 있다. 유용한 전체 텍스트 인덱스 자료구조들이 많이 제안되어왔음에도 불구하고, O(nlogn)-비트 공간을 필요로 하는 공통적인 문제점으로 인하여 보다 효율적으로 공간을 사용할 수 있는 방법에 대한 필요성이 요구되었다. 하지만 기 개발된 압축된 써픽스 배열이나 FM-인덱스와 같은 것들 또한 이미 존재하는 써픽스 배열에서부터 구축되어야 하기 때문에 실제적인 사용 공간을 줄일 수는 없었다. 최근, 써픽스 배열을 구축할 필요 없이 텍스트로부터 직접 압축된 써픽스 배열을 구축할 수 있는 두 가지 알고리즘들이 제안되었다. 본 논문에서는 실험을 통해 자료구조 구축 시간과 구축 시 필요로 하는 최대 사용 공간, 구축이 끝난 후 최종 자료구조의 크기 등을 측정함으로써 이 두 가지 압축된 써픽스 배열 구축 알고리즘과 기존의 써픽스 배열들과의 실제적인 성능을 비교한다.

• 한국응급구조학회지
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• 제16권3호
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• pp.45-62
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• 2012

Purpose : This study was carried out from September 2011 to September 2012 to indicate improvement and performance schemes and planning strategies by way of scenario based practical examination to inspire adaptable capacity to EMS field for Emergency Medical Technician. Methods : In order to improve the examination, a survey was conducted to EMT-Paramedics (Level 1), EMT-Basics (Level 2), and other expert groups. The researchers visited the National Registry of Emergency Medical Technician (NREMT) headquarter and the psychomotor examination site in Ohio in April, 2011. The 21 EMT professors took part in a workshop experiencing the US psychomotor examinations provided by two NREMT examination experts in October, 2011. Results : The results showed that the general plan of new National Practical Examination for EMTs should consist of integrated emergency care examination based on clinical performance and simple skill examination based on objective structured skill protocol Conclusion : The National Practice Examination consists of two sessions and the examinees select the test number randomly in each session. The future examination should include the critical criteria and this criteria should be the decisive factor for the pass or fail.

• 디지털콘텐츠학회 논문지
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• 제15권5호
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• pp.595-602
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• 2014

이미 잘 알려져 있는 클라우드 컴퓨팅은 사용자가 요구하는 컴퓨팅 자원을 최적화하여 유연하고 확장성 있게 지원할 수 있어 다양한 분산컴퓨팅 분야에 적용되고 있다. 클라우드 컴퓨팅은 가상화 기술을 통해 실제적인 구현 및 서비스가 가능하며 여러 가상화 기술과 제품들이 개발, 출시되고 있다. 본 논문에서는 클라우드 컴퓨팅의 가상화 기반으로 교육 실습 환경을 구축하고, 각 실습환경의 성능을 분석하였다. 클라우드 컴퓨팅 기반의 가상화 실습 환경은 최적화된 자원을 제공할 수 있으며, 실습 제공자는 자원 관리의 편리성, 결과에 대한 손쉬운 관리, 실습환경의 성능 및 상태 등의 수월하게 관리하고 파악 할 수 있다. 또한, 다양한 실습환경을 구축하는데 있어 요구되는 시스템 환경을 유연성 있고 신속하게 제공할 수 있어 시스템의 활용성 또한 높아지게 된다. 나아가 가상화 실습환경의 성능 분석을 통하여 구동될 수 있는 교육 어플리케이션의 성능을 미리 평가하고 가늠할 수 있다.

• 한국정보통신학회논문지
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• 제26권2호
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• pp.271-277
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• 2022

PBFT(Practical Byzantine Fault Tolerant)는 분산 네트워크 환경에서 비의도적·의도적 결함을 해결하여 합의를 달성할 수 있는 합의 알고리즘으로 높은 성능과 절대적 최종성을 보장할 수 있다. 하지만 합의 과정에서 반복적으로 발생하는 메시지 브로드캐스팅으로 인해 네트워크의 규모가 증가할수록 네트워크 부하도 커진다. PBFT 알고리즘의 특성상 소규모·프라이빗 블록체인에는 적합하지만, 대규모·퍼블릭 블록체인에 적용하기엔 한계가 있다. PBFT는 블록체인 네트워크의 성능에 영향을 끼치기 때문에 산업에서는 PBFT가 제품 및 서비스에 적합한지 테스트할 수 있어야 하며, 학계에서는 PBFT 성능 향상 연구를 위한 통일된 평가지표와 평가 기술이 필요하다. 본 논문에서는 PBFT 계열 합의 알고리즘을 평가할 수 있는 정량적 지표와 평가 프레임워크에 대해 연구한다. 또한 제안한 PBFT 평가 프레임워크를 사용하여 PBFT의 처리량, 지연시간, 내결함성을 평가한다.

• 한국초전도ㆍ저온공학회논문지
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• 제16권4호
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• pp.7-16
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• 2014

Rare-earth barium copper oxide (REBCO) coated conductor (CC) tapes have already been commercialized but still possess some issues in terms of manufacturing cost, anisotropic in-field performance, $I_c$ response to mechanical loads such as delamination, homogeneity of current transport property, and production length. Development on improving its performance properties to meet the needs in practical device applications is underway and simplification of the tape's architecture and manufacturing process are also being considered to enhance the performance-cost ratio. As compared to low temperature superconductors (LTS), high temperature superconductor (HTS) REBCO CC tapes provide a much wider range of operating temperature and a higher critical current density at 4.2 K making it more attractive in magnet and coil applications. The superior properties of the REBCO CC tapes under magnetic field have led to the development of superconducting magnets capable of producing field way above 23.5 T. In order to achieve its optimum performance, the electromechanical properties under different deformation modes and magnetic field should be evaluated for practical device design. This paper gives an overview of the effects of mechanical stress/strain on $I_c$ in HTS CC tapes due to uniaxial tension, bending deformation, transverse load, and including the electrical performance of a CC tape joint which were performed by our group at ANU in the last decade.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.659-665
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• 2003

This paper presents a Train Communication Network simulator (TCNS) that can be used to evaluate the performance of TCN. TCN was accepted as the standard of the protocol for the communication network in trains. We carry out some simulation tests using the TCNS to show practical uses of the simulator. Results of some simulation tests are also reported. This paper presents a Train Communication Network simulator(TCNS) that can be used to evaluate the performance of TCN. TCN was accepted as the standard of the protocol for the communication network in trains. TCN of fieldbus was adopted as international standardization IEC 61375 in 1999. It has been operating on G7 train in korea. This paper developed TCNS(Train Communication Network simulator) as a simulator for performance evaluation. We can verify TCNS for preventing many kinds of occurring problems between the devices in data-communication. This study was developed TCNS as a simulator for the performance evaluation. We analyzed correlation between token, transmission data per paket and transmission speed of bus, through the TCNS, also analyzed result according to error rate of TCN. We carry out some simulation tests using the TCNS to show practical uses of the simulator. Results of some simulation tests are also reported.

• 유통과학연구
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• 제20권1호
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• pp.99-108
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• 2022

Purpose: This study aims to identify the core competency of sellers on their sales performance in the context of e-commerce, and to verify the mediating effect of innovative sales activities. Research design, data, methodology: A questionnaire survey was carried out to 200 sellers in e-commerce. Exploratory factor analysis and reliability analysis for Cronbach's Alpha were performed to verify the validity and reliability of the and the regression analyses of 5,000 bootstrap samples were carried out to test hypotheses. Results: Based on the analysis, the elements of competencies of sellers in e-commerce such as self-control, trust-building, social interaction skills were positively related to the innovative sales activities and sales performances. Innovative sales activities also affected sales performances. Indirect effects of competencies of sellers on sales performance via innovative sales activities were partially effective depending on variables that brought practical implications. From a practical perspective, the valid competencies found in this study may be applied for the recruitment and selection of sellers. Conclusion: This study shed light on theories of e-commerce sales and sales practices by examining the competencies of sellers in e-commerce compared to those of traditional sellers and by revealing innovative sales activities as the effective mediator for sales performance.