Selection of Excitation Signal Waveform for Improved Performance of Wound-Rotor Resolver*

Author(s):  
A. Farhadi-Beiranvand ◽  
R. Alipour-Sarabi ◽  
Z. Nasiri-Gheidari ◽  
F. Tootoonchian
2002 ◽  
Vol 124 (4) ◽  
pp. 697-705 ◽  
Author(s):  
Chul Kim ◽  
Paul I. Ro

In this study, an approach to obtain an accurate yet simple model for full-vehicle ride analysis is proposed. The approach involves linearization of a full car MBD (multibody dynamics) model to obtain a large-order vehicle model. The states of the model are divided into two groups depending on their effects on the ride quality and handling performance. Singular perturbation method is then applied to reduce the model size. Comparing the responses of the proposed model and the original MBD model shows an accurate matching between the two systems. A set of identified parameters that makes the well-known seven degree-of-freedom model very close to the full car MBD model is obtained. Finally, the benefits of the approach are illustrated through design of an active suspension system. The identified model exhibits improved performance over the nominal models in the sense that the accurate model leads to the appropriate selection of control gains. This study also provides an analytical method to investigate the effects of model complexity on model accuracy for vehicle suspension systems.


Author(s):  
Iman Mansouri ◽  
Elaheh Esmaeili

Nanotechnology refers to the understanding and manipulation of materials on the nanoscale (<100 nm). This can lead to marked changes in material properties and can result in improved performance and new functionality. Nanomaterials with properties such as corrosion resistance, and strength and durability are of particular interests to construction professionals, because, these properties directly affect the selection of construction materials, erection methods, and on-site handling techniques. Applying nanotechnology to construction, in some cases, may result in visionary and paradigm-breaking advances. The incorporation of nanomaterials can improve structural efficiency, durability and strength of cementitious materials and can thereby assist in improving the quality and longevity of structures. This chapter tries to analyze nanotechnology in the context of construction and explores the current scenario of nanotechnology in the construction industry. In order to identify the potential benefits and existing barriers, an extensive literature review is conducted.


2019 ◽  
Vol 71 (2) ◽  
pp. 301-308
Author(s):  
Mubing Yu ◽  
Xiaodong Yu ◽  
Xuhang Zheng ◽  
Hang Qu ◽  
Tengfei Yuan ◽  
...  

Purpose This paper aims to describe a theoretical and experimental research concerning influence of recess shape on comprehensive lubrication performance of high speed and heavy load hydrostatic thrust bearing with a constant flow. Design/methodology/approach The lubrication performance of a hydrostatic thrust bearing with different recess shape under the working conditions of high speed and heavy load has been simulated by using computational fluid dynamics and finite volume method. Findings It is found that the comprehensive lubrication performance of a hydrostatic thrust bearing with circular recess is optimal. The results demonstrate that recess shape has a great influence on the lubrication performance of the hydrostatic thrust bearing. Originality/value The simulation results indicate that to get an improved performance from a hydrostatic thrust bearing with constant flow, a proper selection of the recess shape is essential.


2020 ◽  
Author(s):  
Maya Darnell ◽  
Dominique Lamy

AbstractIn visual search, improved performance when a target appears at a recently cued location is taken as strong evidence that attention was shifted to this cue. Here, we provide evidence challenging the canonical interpretation of spatial-cueing (or cue-validity) effects and supporting the Priority Accumulation Framework (PAF). According to PAF, attentional priority accumulates over time at each location until the search context triggers selection of the highest-priority location. Spatial-cueing effects reflect how long it takes to resolve the competition and can thus be observed even when attention was never shifted to the cue. Here, we used a spatial-cueing paradigm with abruptly onset cues and search displays varying in target-distractor similarity. We show search performance on valid-cue trials deteriorated the more difficult the search, a finding that is incompatible with the standard interpretation of spatial-cueing effects. By using brief displays (Experiment 1) and by examining the effect of search difficulty on the fastest trials (Experiment 2), we invalidate alternative accounts invoking post-perceptual verification processes (Experiment 1) or occasional failures of the onset cue to capture attention (Experiment 2). In Experiment 3, we used a combination of the spatial-cueing and dot-probe paradigms. We show that the events that occurred in both the cue and search displays affected attentional distribution, and that the relative attentional priority weight that accumulated at the target location determined how easily the competition was resolved. These findings fully support PAF’s predictions.Public significance statementMany studies aim at establishing whether certain objects mandatorily capture our attention. Here, we show that there is no “yes-or-no” answer to this question because the context in which an object appears determines whether this object captures attention. We show that our attention is not shifted to the highest-priority object at any given time: instead, information about priority is collected across time until some signal indicates that the appropriate moment for deploying our attention has arrived.Striking failures to notice conspicuous events routinely illustrate how limited our attentional system is: we can attend to very few objects at any given time, and probably to just one. In natural conditions, when we move the focus of our attention from one object to another, we also shift our gaze towards the attended location: this allows us to place the object of most interest in the center of our fovea, which maximizes the quality of its perceptual processing. Tracking the locus of such overt attention is easily achieved by using eye-tracking devices. However, in order to isolate the benefits of attention from the benefits of visual acuity, one must study covert attention – that is, attentional shifts in the absence of eye movements. These shifts are not directly observable and must therefore be inferred using indirect measures of processing.


Euphytica ◽  
2012 ◽  
Vol 185 (1) ◽  
pp. 103-117 ◽  
Author(s):  
Sarah E. Bertrand-Garcia ◽  
Carrie A. Knott ◽  
Niranjan Baisakh ◽  
Prasanta K. Subudhi ◽  
Stephen A. Harrison ◽  
...  

Author(s):  
Lorena Moreno ◽  
Pablo Briñol ◽  
Richard E. Petty

AbstractThe present research examined the role of metacognitive confidence in understanding to what extent people’s valenced thoughts guide their performance in academic settings. First, students were asked to engage in positive or negative thinking about exams in their major area of study (Study 1) or about themselves (Studies 2 and 3). The valence of these primary cognitions was manipulated to be positive or negative. Furthermore, a metacognitive variable, the perceived validity of the primary cognitions, was measured or varied to be relatively high or low. Finally, performance was assessed using a knowledge test (Study 1), a geometric shapes task (Study 2) or a selection of questions from the Graduate Record Examination (Study 3). In accordance with self-validation theory, we predicted and found that metacognitive confidence (relative to doubt) increased the impact of primary cognitions on performance. When thoughts were positive, increased confidence in the primary cognitions improved performance. However, when thoughts were negative, the same confidence validated the negative primary cognitions and reduced performance. Thus, metacognitive confidence can lead to opposite findings on performance depending on whether it validates performance-relevant positive thoughts or negative thoughts. Variations in the perceived validity of thoughts mediated the obtained effects. Therefore, we conclude that understanding the process of thought validation can help in specifying why and when metacognitive confidence is likely to work or to backfire in producing the desired performance effects.


2016 ◽  
Vol 2 (3) ◽  
pp. 129-148
Author(s):  
Debi Setiawan

Abstract- The purpose of this study was to estimate the number of lecturers who will be selected at the end of the year. Selection of lecturers is a way to determine the productivity of lecturers. In Act No. 14 of 2005, article 67, explained that an institution can undertake unilateral termination respectfully, when it ended joint working relationship between lecturers and education providers. At private colleges, the trigger of the selection of lecturers due to the productivity and the number of students. If the number of students is insufficient faculty ratio, while increasing productivity and excellent faculty, it still will do the selection of lecturers. The problem that arises is the imbalance for lecturers who have improved performance. It is necessary for analysis of estimates in the process of selecting lecturers, lecturers and institutions in order to be able to take a stand to solve this problem. Estimation using the design pattern of artificial neural networks (ANN) and methods of propagation, with an error rate of 0.5%. Variables that will be used is the amount of students majoring in IT (Computer Science), MI (Management Information) on campus STMIK Amik Riau, the number of Lecturer (MI and TI), and the final value of faculty productivity. These five variables will be processed on the system of selecting lecturers analysis using backpropagation method, so that the results to be obtained is the number of lecturers who will be affected by the selection of lecturers on campus STMIK Amik Riau.


Sign in / Sign up

Export Citation Format

Share Document