• 제목/요약/키워드: Updating Scheme

검색결과 148건 처리시간 0.028초

전자기 시스템의 다물질 형상 최적설계를 위한 Level Set 방법 적용 (Topological Shape Optimization of Multi-Domain for Electromagnetic Systems using Level Set Method)

  • 이장원;심호경;왕세명
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.23-25
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    • 2008
  • This paper presents a topological shape optimization for electromagnetic system using a Level Set method. The optimization is progressed by updating the implicit Level Set function from the Hamilton-Jacobi equation. The up-wind scheme is used for numerical implementation of the Hamilton-Jacobi equation. In order to validate the proposed optimization, the core part of a C-core actuator is optimized by three cases using different materials; (single steel), (two steels), and (steel and magnet).

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효과적인 2차 최적화 적용을 위한 Minibatch 단위 DNN 훈련 관점에서의 CNN 구현 (Implementation of CNN in the view of mini-batch DNN training for efficient second order optimization)

  • 송화전;정호영;박전규
    • 말소리와 음성과학
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    • 제8권2호
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    • pp.23-30
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    • 2016
  • This paper describes some implementation schemes of CNN in view of mini-batch DNN training for efficient second order optimization. This uses same procedure updating parameters of DNN to train parameters of CNN by simply arranging an input image as a sequence of local patches, which is actually equivalent with mini-batch DNN training. Through this conversion, second order optimization providing higher performance can be simply conducted to train the parameters of CNN. In both results of image recognition on MNIST DB and syllable automatic speech recognition, our proposed scheme for CNN implementation shows better performance than one based on DNN.

새로운 품질보증(品質保證)을 위한 자동검사(自動檢査)데이터의 활용(活用)에 관(關)한 연구(硏究) (A Study on the use of Automotive Testing Data for Updating Quality Assurance Models)

  • 조재입
    • 품질경영학회지
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    • 제11권2호
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    • pp.25-31
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    • 1983
  • Often arrangement for effective product assessment and audit have not been completely satisfactory. The underlying reasons are: (a) The lack of early evidence of new unit quality. (b) The collection and processing of data. (c) Ineffective data analysis techniques. (d) The variability of information on which decision making is based. Because of the nature of the product the essential outputs from an affective QA organization would be: (a) Confirmation of new unit quality. (b) Detection of failures which are either epidemic or slowly degradatory. (c) Identification of failure cases. (d) Provision of management information at the right time to effect the necessary corrective action. The heart of an effective QA scheme is the acquisition and processing of data. With the advent of data processing for quality monitoring becomes feasible in an automotive testing environment. This paper shows how the method enables us to use Automotive Testing data for the cost benefits of QA management.

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A Hybrid Algorithm for Identifying Multiple Outlers in Linear Regression

  • Kim, Bu-yong;Kim, Hee-young
    • Communications for Statistical Applications and Methods
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    • 제9권1호
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    • pp.291-304
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    • 2002
  • This article is concerned with an effective algorithm for the identification of multiple outliers in linear regression. It proposes a hybrid algorithm which employs the least median of squares estimator, instead of the least squares estimator, to construct an Initial clean subset in the stepwise forward search scheme. The performance of the proposed algorithm is evaluated and compared with the existing competitor via an extensive Monte Carlo simulation. The algorithm appears to be superior to the competitor for the most of scenarios explored in the simulation study. Particularly it copes with the masking problem quite well. In addition, the orthogonal decomposition and Its updating techniques are considered to improve the computational efficiency and numerical stability of the algorithm.

A New IEEE 802.11 DCF Utilizing Freezing Experiences in Backoff Interval and Its Saturation Throughput

  • Sakakibara, Katsumi;Taketsugu, Jumpei
    • Journal of Communications and Networks
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    • 제12권1호
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    • pp.43-51
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    • 2010
  • IEEE 802.11 defines distributed coordination function (DCF), which is characterized by CSMA/CA and binary exponential backoff (BEB) algorithm. Most modifications on DCF so far have focused on updating of the contention window (CW) size depending on the outcome of own frame transmission without considering freezing periods experienced in the backoff interval. We propose two simple but novel schemes which effectively utilize the number of freezing periods sensed during the current backoff interval. The proposed schemes can be applied to DCF and its family, such as double increment double decrement (DIDD). Saturation throughput of the proposed schemes is analyzed by means of Bianchi's Markovian model. Computer simulation validates the accuracy of the analysis. Numerical results based on IEEE 802.11b show that up to about 20% improvement of saturation throughput can be achieved by combining the proposed scheme with conventional schemes when applied to the basic access procedure.

Improving Energy Efficiency and Lifetime of Phase Change Memory using Delta Value Indicator

  • Choi, Ju Hee;Kwak, Jong Wook
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제16권3호
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    • pp.330-338
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    • 2016
  • Phase change memory (PCM) has been studied as an emerging memory technology for last-level cache (LLC) due to its extremely low leakage. However, it consumes high levels of energy in updating cells and its write endurance is limited. To relieve the write pressure of LLC, we propose a delta value indicator (DVI) by employing a small cache which stores the difference between the value currently stored and the value newly loaded. Since the write energy consumption of the small cache is less than the LLC, the energy consumption is reduced by access to the small cache instead of the LLC. In addition, the lifetime of the LLC is further extended because the number of write accesses to the LLC is decreased. To this end, a delta value indicator and controlling circuits are inserted into the LLC. The simulation results show a 26.8% saving of dynamic energy consumption and a 31.7% lifetime extension compared to a state-of-the-art scheme for PCM.

다중 심볼 비선형 연속 위상 주파수 천이 변조 (Multiple-symbol Nonlinear Continuous Phase Frequency Shift Keying)

  • 주판유;송명규;홍성권;강성진;강창언
    • 한국통신학회논문지
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    • 제21권10호
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    • pp.2660-2669
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    • 1996
  • In this paper, it is called nonlinear-symbol CPFSK(NCPFSK) which is modulated by the nonlinear function of information carrying phase function within all symbol interval produce time invariant trellis structure. In general, the bit error probability performance of CPFSK modultion scheme within given signal constellation is determined from the number of memory elementsof continuous phase encoder, i.e. number of state. In this paper the number of state of analyticall designed NCPFSK is time invariant. And the nonlinear symbol mapping function of the proposed moudlation produces the nonlinear symbol andthe phase state of the modulation for updating the phase function of NCPFSK. It si shown in this paper nonlinear symbol CPFSK with multiple TCM to make further improvements in d$^{2}$, and analyzed BER performance in AWGN channel envioronments.hannel envioronments.

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An actively controlled prototype for educational buildings

  • Casciati, S.;Faravelli, L.
    • Smart Structures and Systems
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    • 제25권1호
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    • pp.105-109
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    • 2020
  • The authors address the problem of ameliorating or updating existing educational buildings. This building typology is quite sensitive to social and media pressure, mainly when accidents have occurred nearby. When a building is classified as unsatisfactory, the current code requirements oblige one to re-design the building with significant penalty factors in the resistance values. Often the only solution is to destroy the existing facility and to build a new one. When attempting to preserve the existing building, higher levels of safety are demanded by the society and this can only be achieved by innovative system architectures. The authors propose and discuss a prototype that can be easily adopted to retrofit small educational buildings as the ones common in small municipalities. The higher performance is pursued by a special design of the control scheme, with new control devices and special control laws.

An iterative method for damage identification of skeletal structures utilizing biconjugate gradient method and reduction of search space

  • Sotoudehnia, Ebrahim;Shahabian, Farzad;Sani, Ahmad Aftabi
    • Smart Structures and Systems
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    • 제23권1호
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    • pp.45-60
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    • 2019
  • This paper is devoted to proposing a new approach for damage detection of structures. In this technique, the biconjugate gradient method (BCG) is employed. To remedy the noise effects, a new preconditioning algorithm is applied. The proposed preconditioner matrix significantly reduces the condition number of the system. Moreover, based on the characteristics of the damage vector, a new direct search algorithm is employed to increase the efficiency of the suggested damage detection scheme by reducing the number of unknowns. To corroborate the high efficiency and capability of the presented strategy, it is applied for estimating the severity and location of damage in the well-known 31-member and 52-member trusses. For damage detection of these trusses, the time history responses are measured by a limited number of sensors. The results of numerical examples reveal high accuracy and robustness of the proposed method.

모바일 애드혹 네트워크에서 MAC 기반 타임 슬롯 예약을 위한 시간 동기화 알고리즘 (A Time Synchronization Algorithm for a Time-Slot Reservation Based MAC in Mobile Ad-Hoc Networks)

  • 허웅;하우산;유강수;최재호
    • 대한전자공학회논문지TC
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    • 제48권4호
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    • pp.37-46
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    • 2011
  • 시간동기화는 모바일 통신 시스템에서 중요한 역할을 한다. 특히, 통신 개체들 사이에 정확한 시분할 기법이 요구될 때, 네트워크 성능에 영향을 미치는 중요한 요소가 될 수 있다. 본 논문에서는 무선 모바일 애드 혹 네트워크를 위한 새로운 시간 동기화 알고리즘을 제시한다. 본 논문의 주요 목적은 레퍼런스 브로드캐스팅에서 발견된 장점을 활용하여 시간 동기화 패킷의 충돌을 줄이는데 있다. 또한 시간 동기화에 대한 수렴시간을 보장하기 위해 정교한 클럭 갱신 기법을 사용한다. 새롭게 제안한 시간 동기화 알고리즘의 성능을 평가하기 위해 모바일 애드 혹 네트워크에 대한 다양한 시나리오를 구성하고 이를 OPNET으로 구현하여 실험하였다. 컴퓨터 시뮬레이션 결과, 제안한 기법이 시간 동기화의 정확성과 수렴 시간 등의 측면에서 기존의 TSF 방식보다 좋은 성능을 나타내었다.