Use Of Feedforward Research Articles

Using feedforward to improve pre-service teachers’ academic writing and critical thinking skills

IntroductionLiterature to date indicates that constructive, timely, and personalized instructor feedback to student work boosts their academic performance. Peer feedback has been investigated extensively for the past three decades and has demonstrated its effectiveness where students were trained to give quality feedback. Little, however, is known about the use of feedforward as a strategy that focuses on future assignments and paves the way to improved performance.MethodsThis study followed an action research design using a mixed-method approach to examine the impact of feedforward on developing pre-service teachers’ performance on two main skills: critical thinking and academic writing. The teacher researcher followed the same cohort of 14 Emirati pre-service teachers’ over two semesters and used a pre- and post-test to collect quantitative data and a survey to collect qualitative data. Findings in this research study reveal that when using feedforwarding on the same cohort of 14 pre-service teachers over the period of two academic semesters, their scores on the post-test for the two skills improved.ResultsThis new strategy promoted their motivation to improve their performance on the next task and enhanced the quality of their work. Findings also highlight potential reasons that inhibited the participants’ ability to create rich assignments that include content-specific vocabulary and to make connections with the course content.DiscussionThis study implies for curriculum designers at the K-12 level to integrate authentic tasks that engage students with real-world problems and train them on inferring information as a scaffold to the development of their critical thinking skills.

The use of deep learning algorithms to predict mechanical strain from linear acceleration and angular rates of motion recorded from a horse hoof during exercise

Mobility solutions offered by living creatures have inspired engineers to capture their locomotion patterns and then develop novel animal-like robots that use legs for locomotion. Exploring relationships amongst mechanical responses and kinematic parameters is essential for both inventing these robots and enhancing computational techniques. Establishment of accurate physical models to quantify mechanical responses of biological systems is challenging because the corresponding variables are multidimensional, dynamic and highly nonlinear. This encourages the advent of data-driven models in mechanical sciences. This paper delves into the use of feedforward and time-series (dynamic) artificial neural networks (ANN) to analyse experimental data recorded from a racing horse exercised up to 60 km/h to then relate hoof mechanical strain to kinematic parameters recorded experimentally. An inertial measurement unit that was comprised of a sensor and data acquisition system package was designed and mounted on the horse's hoof to measure linear accelerations and angular rates of motion. In addition, an instrumented Aluminium horseshoe that was designed and manufactured and contained: (1) inertial sensors including three orthogonal accelerometers and three orthogonal rate gyroscopes; and, (2) a strain gauge located at the middle of the shoe. The horse was warmed up in a steady gallop at around 35 km/h for 1 km then turned around and galloped at increasing speed to 68 km/h back to the finishing line. Nine kinematic parameters, measured during horse exercise, formed the ANNs input variables: hoof linear accelerations along three orthogonal directions (axe,ay,az), hoof angular rates of motion along three orthogonal directions (Gx, Gy, Gz), shoe linear accelerations along three orthogonal directions (axs, ays, azs), and time. Feedforward and time-series ANNs trained using 1,000,000 experimental instances offered excellent reliability for the prediction of mechanical strain from kinematic measurements, i.e. R ≥ 0.97.

Improving the use of feedforward in Predictive Functional Control to improve the impact of tuning

The classic PFC design is simple and intuitive and yet this paper shows that, counter to expectations, the long standing use of the target information is flawed. Some simple illustrations will demonstrate that what appears sensible can in fact lead to inconsistent decision-making with many common process dynamics. Having explored the source of this inconsistency, the paper shows how it can be ameliorated in a systematic fashion and also investigates the impact of the change on loop sensitivity to disturbances. Several numerical examples demonstrate the efficacy of the proposal in the paper.

The Effect of Servant Leadership on Feedback/ Feed－forward Use of PMS and Management Performance: Focused on NACF

[연구목적] 본 연구는 관리회계 관점에서 농업협동조합 지점장의 서번트 리더십이 PMS의 피드백/피드포워드 이용과 관리적 성과에 미치는 영향을 실증분석 하였다. 본 연구와 같은 접근은 선행연구가 거의 없다는 점에서 의미가 있다.BR[연구방법] 농협 지점을 대상으로 설문조사를 하였으며, 회수된 설문지 중 최종적으로 80부가 통계분석에 사용되었다. PLS(partial least squares)를 이용하여 가설검증을 하였다.BR[연구결과] 연구결과는 다음과 같다. 첫째, 서번트 리더십은 관리적 성과, PMS의 피드백 이용, PMS의 피드포워드 이용에 각각 유의한 정(＋)의 영향을 미친다. 둘째, PMS의 피드백 이용은 관리적 성과에 유의한 정(＋)의 영향을 미치지만 PMS의 피드포워드 이용은 관리적 성과에 유의한 영향을 미치지 않는다.BR[연구의 시사점] 본 연구결과는 농협 지점장의 서번트 리더십이 조직구성원의 성과 향상에 직접적으로 영향을 미칠 뿐만 아니라 PMS의 피드백 이용을 통하여 간접적으로도 영향을 미칠 수 있음을 보여주고 있다.

A study on CSI feedback schemes exploiting feedforward information in FDD cellular systems

AbstractIn frequency‐division duplexing systems, the downlink (DL) channel is usually estimated at the user terminal (UT) and then fed back to the base station (BS) with a limited number of bits. In this paper, we exploit the partial dependency of the uplink (UL) and DL channels to design a new channel‐state information (CSI) reporting procedure that splits the signaling overhead between UL and DL. In particular, the DL channel quantization at the UT is adapted to the UL channel estimated at the BS. The BS estimates and quantizes the UL channel, and then sends to the UT the quantization index as feedforward signaling. This index is used in turn by the UT to select the quantization codebook for the DL channel. Finally, the BS reconstructs the DL channel by either using only the feedback from the UT or merging it with its unquantized knowledge of the UL channel. The number of feedforward and feedback bits is fixed, and the proposed approach balances the signaling overhead between UL and DL. For a given average number of total signaling bits, it turns out that a variable‐length feedback signaling avoids the use of feedforward, while still providing the minimum mean‐square‐error DL channel estimate at the BS. Numerical results prove the validity of proposed fix‐rate and variable‐rate solutions in the scenario of the COST 2100 model.

증권회사 지점의 PMS 피드백, 피드포워드 이용이 조직역량과 조직성과에 미치는 영향

증권회사의 지점조직은 회사 내에서 그 역할과 비중이 크기 때문에 조직역량을 더욱 강화하는 것이 필요하나 관리회계 분야에서 증권회사를 대상으로 한 PMS 이용에 관한 연구는 충분히 이루어지지 않았다. 본 연구에서는 최근에 새롭게 연구되고 있는 PMS 이용방식인 PMS의 피드백/피드포워드 이용이 증권회사 지점조직의 특성과 역할을 반영한 조직역량(민첩성, 시장지향성)과 조직성과(재무성과, 비재무성과)에 미치는 영향을 분석하였다. 실증분석을 위해 금융감독원 금융통계시스템의 증권회사 현황 정보를 바탕으로 2016년 12월 말 기준 국내 법인으로 분류된 43개 증권사 중 국내 지점 수 10개 이상을 보유한 17개 증권사의 999개 지점을 대상으로 132부의 설문지를 회수하였으며, 분석결과는 다음과 같다. 첫째, PMS의 피드백 이용은 재무성과에 유의한 부(-)의 영향을 미치는 것으로 나타났다. 그리고 비재무성과에는 유의한 영향을 미치지 않았으나, 추가분석 결과 민첩성과 시장지향성을 매개로 비재무성과에 긍정적인 영향을 미치는 것으로 나타났다. 이러한 결과는 해석하기 힘든 부분이나, PMS 이용과 관련된 선행연구들의 일반적인 주장을 고려한다면 하나의 시스템에 집중하지 않고 다양한 시스템을 상호보완적으로 이용하는 것이 그 효과성을 높일 수 있다는 측면에서 해석할 수 있을 것이다. PMS의 피드포워드 이용은 재무성과와 비재무성과에 유의한 정(+)의 영향을 미치는 것으로 나타났다. 둘째, PMS의 피드백 이용은 민첩성에 유의한 정(+)의 영향을, 시장지향성에 유의한 정(+)의 영향을 미치는 것으로 나타났다. PMS의 피드포워드 이용은 민첩성과 시장지향성에 유의한 정(+)의 영향을 미치는 것으로 나타났다. 셋째, 민첩성과 시장지향성은 조직성과인 재무성과와 비재무성과에 유의한 정(+)의 영향을 미치는 것으로 나타났다. 따라서 민첩성과 시장지향성은 증권회사 지점조직의 핵심적인 조직역량이라 할 수 있으며, 경쟁우위 확보와 조직성과 향상을 위해 PMS의 이용과 함께 두 역량을 지속적으로 개발해 나가야 할 것이다.

리더십, PMS의 피드백 및 피드포워드 이용, 혁신, 그리고 조직성과 간의 관계에 관한 연구

리더십, PMS의 피드백 및 피드포워드 이용, 혁신, 그리고 조직성과 간의 관계에 관한 연구

PMS의 이용과 임파워먼트 및 창의성간의 관계 : PMS의 피드백·피드포워드 이용을 중심으로

PMS의 이용과 임파워먼트 및 창의성간의 관계 : PMS의 피드백·피드포워드 이용을 중심으로

How Powerful is Feedforward in University Education? A Case Study in Romanian Geography Education on Increasing Learning Efficiency

Theoretical BackgroundProfessors in the Romanian university system plan and organize their activities under the assumption that their students have the subject-specific competences mentioned in the school curricula for the geography class in the pre-university education system or from previous years of university studies. In reality, these students do not have all these competences developed at a superior level, and this is the reason they have difficulties when solving tasks. Frequently, professors notice this situation rather late, after students' involvement in the learning process. At this point, professors cannot change any results and are only able to offer feedback (Cathcart, Greer, & Neale, 2014).In order to prevent students from failing and to fill in the gap between students' necessary knowledge or the competences that professors expect and the real ones that professors actually use, there are diverse educational tools beside the ones from their pedagogical discourse: tests, questionnaires, checklists, worksheets, study guides, instructions, protocols, tutorials, examples, glossaries, and so on. When planning activities and educational tools, professors should anticipate students' problems when learning and should find appropriate ways to formatively intervene. In order to solve the problem by increasing students' success rate and diminishing failure, this study looked for the best educational mechanisms and tools for professors to use during their students' learning process during courses and seminars as well as apart from these formal activities, not after students have finished learning. Some researchers consider feedforward to be such a prevention mechanism (Baker & Zuvela, 2013; Cathcart et al., 2014; Goldsmith, 2008), but opinions about how to use it differ (Duncan, 2007; Gibbs & Simpson, 2004; Hernandez, 2012; Koen, Bitzer, & Beets, 2012; Murtagh & Baker, 2009).During activities, professors often empirically use both feedback and feedforward. In opposition to feedback, feedforward is a controversial subject that has been paid little attention in educational research. So that professors are able to use feedforward from a scientific perspective, this study performs an exploratory research by finding proof for the use of feedforward in comparison with feedback; it also utilizes a quasi-experimental research to test certain tools with a feedforward role. Direct observation, documents, and findings were observed in order to draw a series of theoretical conclusions about feedforward.Understanding and explaining feedforward has been enabled through a series of studies on feedback that focused on presenting the concept (Hattie & Timperley, 2007; Higgins, Hartley, & Skelton, 2001; Lyster & Ranta, 1997), its importance during learning (Brown, 2004; Brown, Harris, & Harnett, 2012; Clarke, 2003; Hattie & Timperley, 2007; Pajares & Graham, 1998), the receiver (Higgins et al., 2001; Irving, Harris, & Peterson, 2011; Wiggins, 2004), the feedback source (Brown et al., 2012; Peterson & Irving, 2008; Topping, 2010), administration conditions (Brown et al., 2012; Hattie & Timperley, 2007), the moment of giving feedback (Hattie & Timperley, 2007), the methods of giving it (Koen et al., 2012), typology (Fink, 2007; Harris, Brown, & Harnett, 2014; Hattie & Timperley, 2007; Irving et al., 2011; Mori, 2011; Murtagh & Baker, 2009; Shute, 2008), its impact (Brown, 2004; Gibbs & Simpson, 2004; Koen et al., 2012), and its efficiency (Akalin & Sucuoglu, 2015; Hattie & Timperley, 2007; Irving et al., 2011; Shute, 2008; Topping, 2010).The neurosciences have frequently researched feedforward using feedforward to trigger: visually selective behavior (Van Rullen & Koch, 2003), the learning capability and storage capacity of feedforward networks (Huang, 2003), and the changes in feedforward postural adjustments following voluntary motor training (Tsao & Hodges, 2007). …

A Review of Feedforward Control Approaches in Nanopositioning for High-Speed SPM

Control can enable high-bandwidth nanopositioning needed to increase the operating speed of scanning probe microscopes (SPMs). High-speed SPMs can substantially impact the throughput of a wide range of emerging nanosciences and nanotechnologies. In particular, inversion-based control can find the feedforward input needed to account for the positioning dynamics and, thus, achieve the required precision and bandwidth. This article reviews inversion-based feedforward approaches used for high-speed SPMs such as optimal inversion that accounts for model uncertainty and inversion-based iterative control for repetitive applications. The article establishes connections to other existing methods such as zero-phase-error-tracking feedforward and robust feedforward. Additionally, the article reviews the use of feedforward in emerging applications such as SPM-based nanoscale combinatorial-science studies, image-based control for subnanometer-scale studies, and imaging of large soft biosamples with SPMs.

Anthropometry of Elderly and Disabled with Special Attention to (Wheel) Chair Design

The need for knowledge about variation of body dimensions of elderly and disabled is even more urgent then for other groups, because these groups are much more dependant on the quality of their equipment than able-bodied people. The usability of aids for people with impairments is closely related to the proper application of anthropometry. This means for example that the right anthropometric data is taken for the target population and that the prototype is tested before being produced. For both parts in the design process our AIS (Anthropometric Information System) software should assist. It consists of an easy interface to receive the right hints at the right place in the design process as described before. AIS forces to choose a target population to design for and gives feedback about the excluded percentage of users through every design decision. This paper describes how products like wheelchairs can be improved with the use of feedforward and feedback about the critical steps in the anthropometrical design process.

Cerebellar function: Coordination, learning or timing?

Theories of cerebellar function have largely involved three ideas: movement coordination, motor learning or timing. New evidence indicates these distinctions are not particularly meaningful, as the cerebellum influences movement execution by feedforward use of sensory information via temporally specific learning.

Differential effects of deep cerebellar nuclei inactivation on reaching and adaptive control.

This study examined the effects of selective inactivation of the cerebellar nuclei in the cat on the control of multijoint trajectories and trajectory adaptation to avoid obstacles. Animals were restrained in a hammock and trained to perform a prehension task in which they reached to grasp a small cube of meat from a narrow food well. To examine trajectory adaptation, reaching was obstructed by placing a horizontal bar in the limb's path. Inactivation was produced by microinjection of the GABA agonist muscimol (0.25-1.0 microg in 1 microL saline). Fastigial nucleus inactivation produced a severe impairment in balance and in head and trunk control but no effect on reaching and grasping. Dentate inactivation slowed movements significantly and produced a significant increase in tip path curvature but did not impair reaching and grasping. Selective inactivation of the anterior and posterior interpositus nuclei did not impair grasping but severely decreased the accuracy of reaching movements and produced different biases in wrist and paw paths. Anterior interpositus inactivation produced movement slowing (wrist speed) and under-reaching to the food well. Wrist and tip paths showed anterior biases and became more curved. Also animals could no longer make anticipatory adjustments in limb kinematics to avoid obstructions but sensory-evoked corrective responses were preserved. Posterior interpositus inactivation produced a significant increase in wrist speed and overreaching. Wrist and tip paths showed a posterior bias and became more curved, although in a different way than during anterior interpositus inactivation. Posterior interpositus inactivation did not impair trajectory adaptation to reach over the obstacle. During inactivation of either interpositus nucleus, all measures of kinematic temporal and spatial variability increased with somewhat greater effects being produced by anterior interpositus inactivation. We discuss our results in relation to the hypothesis that anterior and posterior interpositus have different roles in trajectory control, related possibly to feed-forward use of cutaneous and proprioceptive inputs, respectively. The loss of adaptive reprogramming during anterior interpositus inactivation further suggests a role in motor learning. Comparison with results from our earlier motor cortical study shows that the distinctive impairments produced by inactivation of these two nuclei are similar to those produced by selective inactivation of different zones in the forelimb area of rostral motor cortex. Our findings are consistent with the hypothesis that there are separate functional output channels from the anterior and posterior interpositus nuclei to rostral motor cortex for distinct aspects of trajectory control and, from anterior interpositus alone, for trajectory adaptation.

Synthesis of controllers for arbitrary pole placement in discrete plants including unstable zeros with extensions to adaptive control

This paper presents new simultaneous pole and zero placement schemes based on the use of feedforward and feedback compensators. The main novelty is that the plant is allowed to possess unstable zeros which are not required to be included as zeros of the reference model. The control objective of model-following is achieved by including a feedforward compensator between either the reference or the control signals and the plant output which is incorporated to the usual schemes consisting in a precompensator and a feedback compensator. Basically, two control schemes are presented, but some extensions are given allowing signal feedforward injections at intermediate state variables of the plant instead of the standard injections at the output and the use of blocking filters for the significant frequencies of the output of the feedforward compensator. These schemes lead to two diophantine equations, one being used for standard pole placement while the other being basically used for the placement of zeros in prescribed positions. Several numerical simulations are given to illustrate the capability of the schemes for simultaneous pole and zero placement in the absence and in the presence of noise and their application for adaptive control.

The use of pontryagin estimators for on-line optimal control sequence estimation: The truck backer-upper case study

The Pontryagin optimality principle can be used in conjunction with on-line (or real-time) measurements of state data to build a local model of the control law. In this paper, we discuss and refine the use of this technique in the context of the simple truck backer-upper problem. We first compare the use of feedforward, associative and CMAC neural architectures for the local control model encoding. Algorithm implementation is then done using the CMAC architecture because of its speed of learning and local scoping. We build temporal difference state prediction models for the truck dynamics and then use these predictions to build an estimate of the best control action to take. This control action is constructed from a depth first tree search used in conjunction with optimal control information obtained by solving locally scoped control problems via the Pontryagin optimality principle. The state to control model can then be encoded into a variety of function approximation models.

New roles for feedforward in multivariable control by individual channel design

Abstract Considerable though the benefits of feedback control are, they do not extend to ameliorating adverse multivariable plant dynamical characteristics that are of a structural nature. Feedforward control on the other hand, is shown in this paper to complement multivariable feedback control in a simple but powerful way by providing a strikingly direct resolution of such structural difficulties as non-minimum phase plant behaviour, plant excessive structure sensitivity (uncertainty in the number of channel RHPZs), plant excessive phase sensitivity, and decoupling without increasing system uncertainty. This use of feedforward is believed to be new and is completely different from the well-known application of feedforward control to anticipate and counteract the effect of some known plant disturbance before it affects the output, as widely used in the process industries. The paper ends with a complete statement of the philosophy and methodology of multivariable control, feedforward and feedback, within t...

Organization of voluntary movement

There have recently been a number of advances in our knowledge of the organization of complex, multi-joint movements. Promising starts have been made in our understanding of how the motor system translates information about the location of external targets into motor commands encoded in a body-based coordinate system. Two simplifying strategies for trajectory control that are discussed are parallel specification of response features and the programming of equilibrium trajectories. New insights have also been gained into how neural systems process sensory information to plan and assist with task performance. A number of recent papers emphasize the feedforward use of sensory input, which is mediated through models of the external world, the body's physical plant, and the task structure. These models exert their influence at both reflex and higher levels and permit the preparation of predictive default parameters of trajectories as well as strategies for resolving task demands.

Use of disturbance measurement feedforward in LQG self-tuners

Abstract An explicit adaptive regulator with disturbance measurement feedforward is presented, based on a polynomial LQG design. The addition of an optimized feedforward filter to a feedback regulator involves the solution of only one additional linear polynomial equation. The regulator is designed to handle shape-deterministic disturbances, such as steps, ramps and sinusoids, as well as stochastic disturbances. The properties of the off-line solution in the case of unstable disturbance models are explained. Computational aspects, the computational complexity and the robustness against unmodelled dynamics are discussed. It is argued that the use of feedforward can improve not only the disturbance rejection, but also the stability robustness of an LQG feedback regulator

The Use of Disturbance Measurement Feedforward in LQG Self-Tuners

An explicite adaptive regulator with disturbance measurement feedforward is presented. It is based on a polynomial LQG design. In feedback regulators, the optimization of a feedforward filter involves the solution of only one additional linear polynomial equation. The regulator is designed to handle shape-deterministic disturbances, such as steps, ramps and sinosoids, as well as stochastic disturbances. Computational aspects, the computational complexity and the robustness against unmodelled dynamics are discussed. It is argued that the use of feedforward can improve not only the disturbance rejection, but also the stability robustness of an LQG feedback regulator.