• Title/Summary/Keyword: explicit feedback

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Acupuncture: How Might the Mechanisms of Treatment Have Contributed to the Diagnosis of "Patterns" and Pattern-based Treatments - Speculations on the Evolution of Acupuncture as a Therapy. Implications for Researchers

  • Birch, Stephen
    • Journal of Acupuncture Research
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    • v.35 no.2
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    • pp.47-51
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    • 2018
  • Acupuncture is a complex intervention that manifests varied theories, treatment methods, diagnostic methods and diagnostic patterns. Traditionally based systems of acupuncture (TBSAs) often have their own diagnostic approaches and patterns. Despite the wide variety that can be found amongst TBSAs, is it possible that they share a common background in clinical observation and practice? Research has shown that multiple physiological pathways and mechanisms can be triggered by different acupuncture techniques and methods. It is highly likely that clinicians will have observed some of the effects of these responses and used those observations as feedback to help construct the patterns of diagnosis and their associated treatments. This review briefly examines this possibility. Pattern identification will have developed out of a complex interaction of factors that include; theories current at the time of their development, historical theories, personal choices and beliefs, training, practice methods, clinical observations and the natural feedback that comes from observing how things change once the treatment is applied. Researchers investigating TBSAs and pattern identification need to be more explicit about the systems they have investigated in order to understand the biological basis of pattern identification and their treatments.

Performance Analysis of Flow Control Method Using Virtual Switchs on ATM (ATM에서 가상 스위치를 이용한 흐름 제어 방식의 성능 분석)

  • 조미령;양성현;이상훈
    • Journal of the Korea Computer Industry Society
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    • v.3 no.1
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    • pp.85-94
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    • 2002
  • EMRCA(Explicit Max_min Rate Control Algorithm) switch, which has been proposed in the ATM(Asychronous Transfer Mode) standard, controls the ABR(Available Bit Rate) service traffic in the ATM networks. The ABR service class of ATM networks uses a feedback control mechanism to adapt to varying link capacities. The VS/VD(Virtual Source/Virtual Destination) technique offers the possibility to segment the otherwise end-to-end ABR control loop into separate loops. The improved feedback delay and the control of ABR traffic inside closed segments provide a better performance and QoS(Quality of Service) for ABR connections with respect to throughput, delay, and jitter. This paper is study of an ABR VS/VD flow control method. Linear control theory offers the means to derive correct choices of parameters and to assess performance issues, like stability of the system, during the design phase. The performance goals are a high link utilization, fair bandwidth distribution and robust operation in various environments, which are verified by discrete event simulations. The major contribution of this work is the use of linear control theory to model and design an ABR flow control method tailored for the special layout of a VS/VD switch, the simulation shows that this techniques better than conventional method.

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Analysis of delay compensation in real-time dynamic hybrid testing with large integration time-step

  • Zhu, Fei;Wang, Jin-Ting;Jin, Feng;Gui, Yao;Zhou, Meng-Xia
    • Smart Structures and Systems
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    • v.14 no.6
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    • pp.1269-1289
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    • 2014
  • With the sub-stepping technique, the numerical analysis in real-time dynamic hybrid testing is split into the response analysis and signal generation tasks. Two target computers that operate in real-time may be assigned to implement these two tasks, respectively, for fully extending the simulation scale of the numerical substructure. In this case, the integration time-step of solving the dynamic response of the numerical substructure can be dozens of times bigger than the sampling time-step of the controller. The time delay between the real and desired feedback forces becomes more striking, which challenges the well-developed delay compensation methods in real-time dynamic hybrid testing. This paper focuses on displacement prediction and force correction for delay compensation in the real-time dynamic hybrid testing with a large integration time-step. A new displacement prediction scheme is proposed based on recently-developed explicit integration algorithms and compared with several commonly-used prediction procedures. The evaluation of its prediction accuracy is carried out theoretically, numerically and experimentally. Results indicate that the accuracy and effectiveness of the proposed prediction method are of significance.

Analysis of the congestion control scheme with the discard eligibility bit for frame relay networks (프레임 릴레이망에서의 DE 비트를 사용하는 혼잡제어 방식의 성능해석에 관한 연구)

  • 이현우;우상철;윤종호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.9
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    • pp.2027-2034
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    • 1997
  • Frame relay is a fast packet switching technology that performs relaying and multiplexing frames with variable lengths over a wide area link at the T1 or E1 speed, by elminating error and flow control in the network. In frame relay networks, congestion control is typically performed through the rate enforcement with a discard eligibility (DE) bit, and the explicit negative feedback meachanisms using explicit congetion notification bits. In this paper, we consider the congestiong control scheme using the rate enforcement mechanism with DE bit for frame relay network. Assuming that each frame with exponentially distributed length arrives according to the Poission fashion, we can treat the frame relay switch as an M/M/1/K priority queueing system with pushout basis. We analyze and present the blocking probabilities and waiting time distributions of frames.

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The Effectiveness of Explicit Form-Focused Instruction in Teaching the Schwa /ə/ (영어 약모음 /ə/ 교수에 있어서 명시적 Form-Focused Instruction의 효과 연구)

  • Lee, Yunhyun
    • The Journal of the Korea Contents Association
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    • v.20 no.8
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    • pp.101-113
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    • 2020
  • This study aimed to explore how effective explicit form-focused instruction (FFI) is in teaching the schwa vowel /ə/ to EFL students in a classroom setting. The participants were 25 female high school students, who were divided into the experimental group (n=13) and the control group (n=12). One female American also participated in the study for a speech sample as a reference. The treatment, which involves shadowing model pronunciation by the researcher and a free text-to-speech software and the researcher's feedback in a private session, was given to the control group over a month and a half. The speech samples, for which the participants read the 14 polysyllabic stimulus words followed by the sentences containing the words, were collected before and after the treatment. The paired-samples t test and non-parametric Wilcoxon signed-rank test were used for analysis. The results showed that the participants of the experimental group in the post-test reduced the duration of the schwa by around 40 percent compared to the pre-test. However, little effect was found in approximating the participants' distribution patterns of /ə/ measured by the F1/F2 formant frequencies to the reference point, which was 539 Hz (F1) by 1797 Hz (F2). The findings of this study suggest that explicit FFI with multiple repetitions and corrective feedback is partly effective in teaching pronunciation.

Exponential Stabilization of a Class of Underactuated Mechanical Systems using Dynamic Surface Control

  • Qaiser, Nadeem;Iqbal, Naeem;Hussain, Amir;Qaiser, Naeem
    • International Journal of Control, Automation, and Systems
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    • v.5 no.5
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    • pp.547-558
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    • 2007
  • This paper proposes a simpler solution to the stabilization problem of a special class of nonlinear underactuated mechanical systems which includes widely studied benchmark systems like Inertia Wheel Pendulum, TORA and Acrobot. Complex internal dynamics and lack of exact feedback linearizibility of these systems makes design of control law a challenging task. Stabilization of these systems has been achieved using Energy Shaping and damping injection and Backstepping technique. Former results in hybrid or switching architectures that make stability analysis complicated whereas use of backstepping some times requires closed form explicit solutions of highly nonlinear equations resulting from partial feedback linearization. It also exhibits the phenomenon of explosions of terms resulting in a highly complicated control law. Exploiting recently introduced Dynamic Surface Control technique and using control Lyapunov function method, a novel nonlinear controller design is presented as a solution to these problems. The stability of the closed loop system is analyzed by exploiting its two-time scale nature and applying concepts from Singular Perturbation Theory. The design procedure is shown to be simpler and more intuitive than existing designs. Design has been applied to important benchmark systems belonging to the class demonstrating controller design simplicity. Advantages over conventional Energy Shaping and Backstepping controllers are analyzed theoretically and performance is verified using numerical simulations.

MFMAP: Learning to Maximize MAP with Matrix Factorization for Implicit Feedback in Recommender System

  • Zhao, Jianli;Fu, Zhengbin;Sun, Qiuxia;Fang, Sheng;Wu, Wenmin;Zhang, Yang;Wang, Wei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.5
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    • pp.2381-2399
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    • 2019
  • Traditional recommendation algorithms on Collaborative Filtering (CF) mainly focus on the rating prediction with explicit ratings, and cannot be applied to the top-N recommendation with implicit feedbacks. To tackle this problem, we propose a new collaborative filtering approach namely Maximize MAP with Matrix Factorization (MFMAP). In addition, in order to solve the problem of non-smoothing loss function in learning to rank (LTR) algorithm based on pairwise, we also propose a smooth MAP measure which can be easily implemented by standard optimization approaches. We perform experiments on three different datasets, and the experimental results show that the performance of MFMAP is significantly better than other recommendation approaches.

Observable Behavior for Implicit User Modeling -A Framework and User Studies-

  • Kim, Jin-Mook;Oard, Douglas W.
    • Journal of the Korean Society for Library and Information Science
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    • v.35 no.3
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    • pp.173-189
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    • 2001
  • This paper presents a framework for observable behavior that can be used as a basis for user modeling, and it reports the results of a pair of user studies that examine the joint utility of two specific behaviors. User models can be constructed by hand, or they can be teamed automatically based on feedback provided by the user about the relevance of documents that they have examined. By observing user behavior, it is possible to obtain implicit feedback without requiring explicit relevance judgments. Four broad categories of potentially observable behavior are identified : examine, retain, reference, and annotate, and examples of specific behaviors within a category are further subdivided based on the natural scope of information objects being manipulated . segment object, or class. Previous studies using Internet discussion groups (USENET news) have shown reading time to be a useful source of implicit feedback for predicting a user's preferences. The experiments reported in this paper extend that work to academic and professional journal articles and abstracts, and explore the relationship between printing behavior and reading time. Two user studies were conducted in which undergraduate students examined articles or abstracts from the telecommunications or pharmaceutical literature. The results showed that reading time can be used to predict the user's assessment of relevance, that the mean reading time for journal articles and technical abstracts is longer than has been reported for USENET news documents, and that printing events provide additional useful evidence about relevance beyond that which can be inferred from reading time. The paper concludes with a brief discussion of the implications of the reported results.

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An LMI-based PID Control Design Method for Uncertain MIMO Systems (불확실성을 갖는 MIMO 시스템을 위한 선형행렬부등식 기반 PID 제어기 설계 방법)

  • Lee, Jae-Kwan;Choi, Han-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.9
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    • pp.750-754
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    • 2005
  • This paper deals with the design problem of multivariable PID controllers guaranteeing the closed-loop system stability and a prescribed $H_\infty$ norm bound constraint. We reduce the problem to the static output feedback stabilization problem. We derive a necessary and sufficient condition f3r the existence of PID controllers and we give an explicit formula of PID controllers. We also give an existence condition of PID controllers guaranteeing a prescribed decay rate. Finally, we give an LMI-based design algorithm, together with a numerical design example.

A Linear Sliding Surface Design Method for a Class of Uncertain Systems with Mismatched Uncertainties (불확실성이 매칭조건을 만족시키지 않는 선형 시스템을 위한 슬라이딩 평면 설계 방법)

  • 최한호
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.11
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    • pp.861-867
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    • 2003
  • We propose a sliding surface design method for linear systems with mismatched uncertainties in the state space model. In terms of LMIs, we derive a necessary and sufficient condition for the existence of a linear sliding surface such that the reduced-order equivalent sliding mode dynamics restricted to the linear sliding surface is not only stable but completely invariant to mismatched uncertainties. We give an explicit formula of all such linear switching surfaces in terms of solution matrices to the LMI existence condition. We also give a switching feedback control law, together with a design algorithm. Additionally, we give some hints for designing linear switching surfaces guaranteeing pole clustering constraints or linear quadratic performance bound constraints. Finally, we give a design example in order to show the effectiveness of the proposed methodology.