• 제목/요약/키워드: Selective use

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LCOS기반의 파장선택스위치 빔제어용 컴퓨터 생성 홀로그램 (Computer Generated Hologram for Beam Control of LCOS based Wavelength Selective Switch)

  • 이용민;한창호
    • 한국산학기술학회논문지
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    • 제17권6호
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    • pp.744-749
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    • 2016
  • 본 논문은 차세대 ROADM을 구성하는 핵심기술인 LCOS를 이용한 파장선택 스위치에서 LCOS 소자의 빔 제어방법으로 컴퓨터 생성 홀로그램 설계에 관한 논문이다. LCOS 소자를 이용한 빔 제어방법으로 일반적으로 grating 패턴을 사용하지만 본 논문에서는 컴퓨터 생성 홀로그램을 도입하여 보다 높은 광효율의 파장선택 스위치 구현이 가능하도록 하였다. LCOS 소자의 위상변조 특성을 이용하여 5개의 출력 포트와 40 채널의 다중파장의 빔 제어를 할 수 있는 파장선택 스위치의 홀로그램 설계방법을 제시하였다. Gerchberg-Saxton 알고리즘을 적용한 멀티레벨 위상변조 홀로그램을 설계하였으며 다른 출력 포트와 채널을 갖는 파장선택 스위치 시스템에도 쉽게 적용이 가능하다. 타겟 이미지의 밝기정보를 사전에 입력하고 역프리에 변환을 통해 위상정보를 추출하여 홀로그램에 저장한 후 임의의 광원의 밝기정보를 합성하여 프리에 변환하는 방법으로 타겟 이미지의 밝기정보를 예측하는 방법을 사용한다. 5개의 출력포트용 홀로그램을 제작하여 검증실험장치의 재생 이미지의 출력특성을 통해 본 연구방법으로 설계된 홀로그램의 유용성을 검증하였고 40채널 파장선택 스위치 제어용 홀로그램 설계방법을 제시하였다.

선택적 중재합의의 유효성에 대한 판례분석 - 대법원 판례를 중심으로 - (Analysis of Judgements on the validity of selective/unilateral Arbitration Agreement - In case of the Supreme Court's Judgements -)

  • 정영환
    • 한국중재학회지:중재연구
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    • 제19권3호
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    • pp.3-24
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    • 2009
  • This article discusses the validity of selective/unilateral arbitration agreement that provides arbitration as one of several dispute resolution methods. The Supreme Court has held selective/unilateral arbitration agreement that is conditional invalidity since the judgement of 2003Da318 decided on Aug. 22, 2003: In the following judgements of 2004Da42166 decided on Nov. 11, 2004 and 2005Da12452 decided on May 27, 2005, the Court stated that the selective/unilateral arbitration agreement that stipulates to resolve a dispute through arbitration or mediation would be valid as an effective arbitration agreement only if a party elects and proceeds an arbitration proceeding and another party responses to the arbitration proceeding without any objection. The definition of arbitration agreement, the formation of selective/unilateral arbitration agreement, the summary of relative judgements and academic theories will be reviewed in order to examine the appropriateness of the series of judgements of the Supreme Court. Based on such reviews, this article will investigate the adequacy of the Supreme Court judgements from the perspectives of i) the principle of party autonomy, ii) the structure of dispute resolution methods, iii) legal provisions of Arbitration Act, iv) legal stability, and v) the policy to revitalize the use of arbitration. At conclusion, this article will suggest the change of precedents of the Supreme Court's judgements with regard to the selective arbitral agreement.

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노인환자에서 위장관계 및 심혈관계 부작용 발생 예방을 위한 NSAIDs 사용의 적절성 평가 (Evaluation of Proper Use of NSAIDs to Prevent Gastrointestinal and Cardiovascular Problems in Elderly Patients)

  • 주성락;방준석
    • 한국임상약학회지
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    • 제24권1호
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    • pp.15-25
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    • 2014
  • Background: Elderly patients with gastrointestinal (GI) and cardiovascular (CV) risk factors may be more easily exposed to NSAID-related side effects (SEs). Based on the ACG guideline of year 2009, the aim of the study is to evaluate proper use of NSAIDs and gastroprotective drugs according to the degree of GI and CV risk strengths in the patients. Methods: Retrospectively surveyed 410 elderly patients with NSAIDs for more than 30 days at a general hospital in Korea. GI risk factor includes age, ulcer history, high-dose NSIADs, concurrent aspirin use, steroids or anticoagulants. CV risk factor includes angina, myocardial infarction, cerebral infarction, atrial fibrillation or coronary intervention requiring low-dose aspirin. These factors were classified as high/low cardiovascular groups and high/moderate/low GI groups. Results: There were 14 patients in high CV risk group and high GI risk group. The group was recommended not to use NSAIDs as it is not adequate. There were 101 patients in high CV risk group and moderate GI risk group. This group was recommended to use naproxen and PPI/misoprostol. But all patients except one were not adequate. There were 9 patients in low CV risk group and high GI risk group. This group was recommended to use selective COX-2 inhibitor and PPI/misoprostol. 5 cases were proper while 4 cases did not. There were 285 patients in low CV risk and moderate GI risk group who were recommended to use non selective NSAIDs and PPI/misoprostol or selective COX-2 inhibitor only. 103 patients were proper while 182 patients not adequate. Overall, the SEs were higher in those cases for inadequate use of drugs comparing to the adequate. CV SEs were statistically significant. However, SEs for each risk groups were different. For the case of low CV risk group and high/moderate GI risk group, the inadequate use of drugs makes the SE high and the other groups are not. Also, it was not statistically significant. Conclusions: In elderly patients, the inappropriate use of NSAIDs can increase the risk of the disease. Therefore, GI and CV risk must be considered simultaneously, and the proper use of NSAIDs and gastroprotective drugs for each risk groups should be reconsidered.

Joint Compensation of Transmitter and Receiver IQ Imbalance in OFDM Systems Based on Selective Coefficient Updating

  • Rasi, Jafar;Tazehkand, Behzad Mozaffari;Niya, Javad Musevi
    • ETRI Journal
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    • 제37권1호
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    • pp.43-53
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    • 2015
  • In this paper, a selective coefficient updating (SCU) approach at each branch of the per-tone equalization (PTEQ) structure has been applied for insufficient cyclic prefix (CP) length. Because of the high number of adaptive filters and their complex adaption process in the PTEQ structure, SCU has been proposed. Using this method leads to a reduction in the computational complexity, while the performance remains almost unchanged. Moreover, the use of set-membership filtering with variable step size is proposed for a sufficient CP case to increase convergence speed and decrease the average number of calculations. Simulation results show that despite the aforementioned algorithms having similar performance in comparison with conventional algorithms, they are able to reduce the number of calculations necessary. In addition, compensation of both the channel effect and the transmitter/receiver in-phase/quadrature-phase imbalances are achievable by these algorithms.

Fabricating a Ceramic-Pressed-to-Metal Restoration with Computer-Aided Design, Computer-Aided Manufacturing and Selective Laser Sintering: A Case Report

  • Lee, Ju-Hyoung;Kim, Hyung Gyun
    • Journal of Korean Dental Science
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    • 제8권1호
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    • pp.41-47
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    • 2015
  • Even though a conventional metal ceramic restoration is widely in use, its laboratory procedure is still technique-sensitive, complex, and time-consuming. A ceramic-pressed-to-metal restoration (PTM) can be a reliable alternative. However, simplified laboratory procedure for a PTM is still necessary. The article is to propose a technique that reduces time and effort to fabricate a PTM with the aid of computer-aided design, computer-aided manufacturing and selective laser sintering technologies.

Selective Production of Epothilone B by Heterologous Expression of Propionyl-CoA Synthetase in Sorangium cellulosum

  • Han, Se-Jong;Park, Sang-Woo;Kim, Byung-Woo;Sim, Sang-Jun
    • Journal of Microbiology and Biotechnology
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    • 제18권1호
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    • pp.135-137
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    • 2008
  • The metabolic engineering of epothilones, as secondary metabolites, was investigated using Sorangium cellulosum to achieve the selective production of epothilone B, a potent anticancer agent. Thus, the propionyl-CoA synthetase gene (prpE) from Ralstonia solanacearum was heterologously expressed in S. cellulosum to increase the production of epothilone B. Propionyl-CoA synthetase converts propionate into propionyl-CoA, a potent precursor of epothilone B. The recombinant S. celluloslim containing the prpE gene exhibited a significant increase in the resolution of epothilones B/A, with an epothilone B to A ratio of 127 to 1, which was 100 times higher than that of the wild-type cells, demonstrating its potential use for the selective production of epothilone B.

공간 데이타 큐브의 선택적 실체화에 관한 연구 (A Study on the Selective Materialization of Spatial Data Cube)

  • 이기영
    • 한국컴퓨터정보학회논문지
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    • 제4권4호
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    • pp.69-76
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    • 1999
  • 최근에 공간 데이타 웨어하우스에서 자주 사용되어지고 질의 응답 시간이 많이 걸리는 복잡한 공간 집계 질의들은 미리 그 결과를 계산하여 실체화시키는 방법들이 연구되고 있다. 본 논문에서는 기존의 선택적 실체화 알고리즘에 대한 개선 방안으로 공간 뷰의 공간 측정에 대한 공간 연산의 계산 시간과 접근 빈도를 고려하여 선택적 실체화에 대한 방법을 제시하고 개선된 선택적 실체화 알고리즘을 제안한다.

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페이딩 매질에서 대역확산 주파수도약 통신시스템의 전송특성 (Transmission Characteristics of FFH-SS Communication System in Fading Media)

  • 김원후;전계석
    • 한국음향학회지
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    • 제6권1호
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    • pp.5-14
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    • 1987
  • 이 논문은 시간 및 주파수 선택성페이딩이 동시에 존재하는 채널에서 대역확산 주파수 도약통신시스템의 전송특성을 제시한다. 수신기는 승적합산기를 포함한 binary noncoherent matched-filter fast FH-SS시스템이다. 이 시스템에서 SNR, 채널 선택도, 전력비 등의 변동에 따른 오차확률은 데이터율을 고려하지 않고 다이버시티 개념을 사용하여 구하였으며, 오차확율에 대한 데이터를 분석한 결과 FH-SS 시스템은 시간 선택성 페이딩 채널에서 전송특성이 우수함을 나타내었다.

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Decision Feedback Detector for Space-Time Block Codes over Time-Varying Channels

  • Ahn, Kyung-Seung;Baik, Heung-Ki
    • 한국통신학회논문지
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    • 제28권5C호
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    • pp.506-513
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    • 2003
  • Most existing space-time coding (STC) schemes have been developed for flat fading channels. To obtain antenna diversity gain, they rely on channel state information (CSI) required at the receiver through channel estimation techniques. This paper proposes a new decision feedback decoding scheme for Alamouti-based space-time block coding (STBC) transmission over time-selective fading channels. In wireless channels, time-selective fading effects arise mainly due to Doppler shift and carrier frequency offset, Modelling the time-selective fading channels as the first-order Gauss-Markov processes, we use recursive algorithms such as Kalman filtering, LMS and RLS algorithms for channel tracking. The proposed scheme consists of the symbol decoding stage and channel tracking algorithms. Computer simulations confirm that the proposed scheme shows the better performance and robustness to time-selectivity.

Fast Screening of Harmful Disinfectants in Household Products via Low-Temperature Plasma Ionization-Mass Spectrometry

  • Lee, Hyoung Jun;Kweon, Gi Ryang;Yim, Yong-Hyeon
    • Mass Spectrometry Letters
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    • 제8권2호
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    • pp.44-47
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    • 2017
  • Isothiazolinone derivatives are widely used in consumer products as disinfectants or preservatives, but there are growing concerns about their impact on human health. Therefore, rapid screening of these biocides is very important for proper control and regulation of potentially hazardous substances. To this end, low-temperature plasma (LTP) ionization mass spectrometry (MS) was investigated to demonstrate its potential for direct and selective analysis of isothiazolinones from sprayed aerosol samples. Benzisothiazolinone (BIT) was clearly identified from a commercial fabric deodorant using LTP ionization MS and MS/MS. LTP allowed selective ionization of BIT directly from the simply sprayed aerosol sample and illustrated its potential for fast screening without sample pre-treatments. Selective nature of LTP ionization, on the other hands, implicates use of LTP ionization MS as a general screening method for specific groups of hazardous chemicals in commercial products.