• Title/Summary/Keyword: deterministic

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Deterministic Nonlinear Control of Two-Link Flexible Arm (2관절 유연한 로봇 팔에 대한 비선형 제어)

  • Han, Jong-Kil;Son, Yong-Su
    • The Journal of the Korea institute of electronic communication sciences
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    • v.4 no.3
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    • pp.236-242
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    • 2009
  • When two-link flexible arm is rotated about an joint axis, transverse vibration may occur. In this paper, vibration dynamics of flexible robot arm is modeled by using Bernoulli-Euler beam theory and Lagrange equation. Using the fact that matrix $\dot{D}$-2C is skew symmetric, new controllers which have a simplified structure with less computational burden is proposed. Lyapunov stability theory is applied to achieve a stable deterministic nonlinear controller for the regulation of joint angle.

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Transient Simulation of Graphene Sheets using a Deterministic Boltzmann Equation Solver

  • Hong, Sung-Min
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.17 no.2
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    • pp.288-293
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    • 2017
  • Transient simulation capability with an implicit time derivation method is a missing feature in deterministic Boltzmann equation solvers. The H-transformation, which is critical for the stable simulation of nanoscale devices, introduces difficulties for the transient simulation. In this work, the transient simulation of graphene sheets is reported. It is shown that simulation of homogeneous systems can be done without abandoning the H-transformation, as much as a specially designed discretization method is employed. The AC mobility and step response of the graphene sheet on the $SiO_2$ substrate are simulated.

Reliability Based Design Optimization of the Softwater Pressure Tank Considering Temperature Effect (온도영향을 고려한 연수기 압력탱크의 신뢰성 최적설계)

  • Bae Chul-Ho;Kim Mun-Seong;Suh Myung-Won
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.10
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    • pp.1458-1466
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    • 2004
  • Deterministic optimum designs that are obtained without consideration of uncertainties could lead to unrealiable designs. Such deterministic engineering optimization tends to promote the structural system with less reliability redundancy than obtained with conventional design procedures using the factor of safety. Consequently, deterministic optimized structures will usually have higher failure probabilities than unoptimized structures. This paper proposes the reliability based design optimization technique fur apressure tank considering temperature effect. This paper presents an efficient and stable reliability based design optimization method by using the advanced first order second moment method, which evaluates a probabilistic constraint for more accuracy. In addition, the response surface method is utilized to approximate the performance functions describing the system characteristics in the reliability based design optimization procedure.

Performance Evaluation of Vehicle Routing Algorithms in a Stochastic Environment (Stochastic 환경에서 확정적 차량경로결정 해법들의 성능평가)

  • 박양병
    • Korean Management Science Review
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    • v.17 no.2
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    • pp.175-187
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    • 2000
  • The stochastic vehicle routing problem (VRP) is a problem of growing importance since it includes a reality that the deterministic VRP does not have. The stochastic VRP arises whenever some elements of the problem are random. Common examples are stochastic service quantities and stochastic travel times. The solution methodologies for the stochastic VRP are very intricate and regarded as computationally intractable. Even heuristics are hard to develope and implement. On possible way of solving it is to apply a solution for the deterministic VRP. This paper presents a performance evaluation of four simple heuristic for the deterministic VRP is a stochastic environment. The heuristics are modified to consider the time window constraints. The computational results show that some of them perform very well in different cases of the stochastic VRP.

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Deterministic Data Communication Architecture for Safety-Critical Networks in Nuclear Power Plants (원전 안전통신망을 위한 결정론적 데이터 통신 구조)

  • Park, Sung-Woo;Kim, Dong-Hoon
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.5
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    • pp.199-204
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    • 2006
  • To develop a safety-critical network in nuclear power plants that puts more stringent requirements than the competitive commercial ones do, we establish four design criteria - deterministic communication, explicit separation/isolation structure, reliability, verification & validation. According to those design criteria, the fundamental design elements are chosen as follows - a star topology, point-to-point physical link, connection-oriented link control and fixed allocation access control. After analyzing the design elements, we also build a communication architecture with TDM (Time Division Multiplexing) bus switching scheme. Finally, We develop a DDCNet (Deterministic Data Communication Network) based on the established architecture. The DDCNet is composed of 64 nodes and guarantees the transmission bandwidth of 10Mbps and the delay of 10 msec for each node. It turns out that the DDCNet satisfies the aforementioned design criteria and can be adequately utilized for our purpose.

Reliability-Based Design of Vertical Drain Method Considering Uncertainties in Geotechnical Property (연약지반의 불확실성을 고려한 연직배수공법의 신뢰성 설계)

  • Kim, Byung-Il;Sah, Sang-Ho;Kim, Bang-Sig;Kim, Soo-Sam
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.1148-1154
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    • 2006
  • Composite discharge capacity tests and smear effect tests are carried out to estimate the parameters for the reliability-based design of vertical drain method. Also the probabilistic and deterministic solutions of radial consolidation theory are presented. It compared to the result of reliability-based design and that of deterministic design using the tested and estimated parameters. The results indicated that the drain spacing is larger the deterministic method than the probabilistic method because the former is not considered the uncertainties in the properties of soil. The divergence of methods is dependent on the probability of achieving target degree of consolidation by a given time and the coefficient of variation(COV) of the coefficient of horizontal consolidation$(c_h)$.

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Track-Following Control of a Hard Disk Drive Actuator Using Nonlinear Robust Deterministic Control (비선형 견실 확정제어를 이용한 하드디스크 드라이브의 트랙추종제)

  • Wie, Byung-Yeol;Kang, Chul-Goo
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.10
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    • pp.881-887
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    • 2000
  • There are significant nonlinearities and uncertainties in hard disk drive actuators. In particular, pivot bearing nonlinearity and repeatable run-out make track-following control difficult as track density increases. In this paper, we design a robust track-following controller using a robust deterministic control scheme in which the pivot bearing nonlinearity and repeatable run-out are considered as uncertainties. Simulation study is conducted to evaluate the control performance of the proposed control scheme.

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Deterministic Bipolar Compressed Sensing Matrices from Binary Sequence Family

  • Lu, Cunbo;Chen, Wengu;Xu, Haibo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.6
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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.

On IPv6 Traceback using Deterministic Packet Marking

  • Amin, Syed Obaid;Hong, Choong-Seon;Kim, Il-Joong
    • Proceedings of the Korea Information Processing Society Conference
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    • 2005.11a
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    • pp.977-980
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    • 2005
  • The motivation of IP traceback is to identify the true source of an IP datagram in internet. These techniques now emerging as effective deterrent for current cyber threats, especially (D)DoS. Deterministic Packet Marking (DPM) is one of the algorithm used for IP traceback. This paper elucidates the implementation of deterministic packet marking scheme on IPv6 networks. The proposed scheme is capable of single packet traceback. We also examined the issues regarding IPv6 header and show that this scheme is practical, scalable, efficient and can be implemented on existing IPv6 networks easily.

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Convergence of MAP-EM Algorithms with Nonquadratic Smoothing Priors

  • Lee, Soo-Jin
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.361-364
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    • 1997
  • Bayesian MAP-EM approaches have been quite useful or tomographic reconstruction in that they can stabilize the instability of well-known ML-EM approaches, and can incorporate a priori information on the underlying emission object. However, MAP reconstruction algorithms with expressive priors often suffer from the optimization problem when their objective unctions are nonquadratic. In our previous work [1], we showed that the use of deterministic annealing method greatly reduces computational burden or optimization and provides a good solution or nonquadratic objective unctions. Here, we further investigate the convergence of the deterministic annealing algorithm; our experimental results show that, while the solutions obtained by a simple quenching algorithm depend on the initial conditions, the estimates converged via deterministic annealing algorithm are consistent under various initial conditions.

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