Quadrupole Electromagnetic Linear Positioning System (QELPS):: Optimal Design, Modelling and Analysis for Linear Motion Application

In linear motion systems, including linear motors and actuators, precise and controlled linear motion is provided for various applications. However, they have several drawbacks: high costs, complexity, limited stroke length, high energy consumption, speed limitations, heat generation, noise and vibration, limited load capacity, environmental considerations, and integration challenges. High costs are especially significant for applications requiring high precision. The components' complexity and additional control electronics can increase maintenance and trouble-shooting requirements. Ensuring accurate and efficient operation necessitates regular maintenance. The limitation in stroke length, determined by the drive's size and guide length, can pose challenges for applications requiring long strokes. High energy consumption can be a concern, and speed limitations may be challenging. Managing heat generation is crucial to prevent component damage. Noise and vibration can be problematic, particularly in quiet applications. Integration challenges can arise when dealing with complex systems or automation processes. To overcome some of these drawbacks, an innovative coil configuration design for linear positioning system applications is proposed. The proposed design focuses on the Quadrupole Electromagnetic linear Positioning System (QELPS), comprising four coils generating a uniform electromagnetic field to produce a Lorentz force on the slider. The QELPS design is meticulously crafted using 3D modeling in ANSYS software, and the magnetic characteristics indicate the potential for scaling this model to different levels. The power circuit of the QELPS is simulated using ANSYS Simplorer and incorporates silicon-controlled rectifiers (SCR) and a pulse width modulation (PWM) pulse generator. The design achieves a force of 27.6 newtons with the paper presenting current and force plots in comprehensive detail. Furthermore, an interactive design algorithm is introduced, facilitating the customization of this model for various linear track dimensions. This research aims to advance linear drive technology and enhance linear motion applications by developing this new coil configuration design and harnessing the Quadrupole Electromagnetic System

Multiple Venous Malformations as a Cause of Pulsatile Tinnitus.

INTRODUCTION: Pulsatile tinnitus is a relatively common presentation in otolaryngology clinics, most cases of which have a treatable cause. This presentation warrants a thorough workup to identify treatable, and rule out life-threatening, etiologies. We present a case of a patient with pulsatile tinnitus arising from multiple dilated venous channels in the head and neck. Case Presentation. We present the case of a 65-year-old Caucasian female with a two-year history of progressive, bilateral pulsatile tinnitus, which had become debilitating. Computed-tomographic angiography (CTA) studies ruled out an intracranial vascular cause for her symptoms. However, computed tomography (CT) scanning and magnetic resonance imaging (MRI) revealed multiple dilated bilateral, low-flow, venous channels throughout the head and neck. The proximity of such dilated venous channels to the temporal bone provides a route for sound to be transmitted to the inner ear. CONCLUSION: Arterial, venous, and systemic etiologies can cause pulsatile tinnitus. Arteriovenous malformations (AVMs) of the head and neck represent less than 1% of cases. In our patient, dilated low-flow venous malformations are the likely source of her symptoms, which is the first reported case in the literature.Peer Reviewe

Post-stroke patients’ rehabilitation exercise assessment from Vicon-based skeletal angle displacement using Convolutional Neural Network

Stroke is one of the leading causes of neurological disorders, and around 1 million people suffer from stroke in the United States. Two-thirds of these individuals survive and requires rehabilitation exercise in their daily life to improve their quality of life. Automatically assessing these performed rehabilitation movements is inherent to improving post-stroke patients\u27 overall physical condition. With the recent growth in computer vision research, people are using motion capture systems to perform physical exercises, workouts, and training at their preferred place, as these systems occupy less space but provide flexibility to the users. This work assesses post-stroke patient rehabilitation movement from full-body skeletal joint displacement data sensed through vision-based Vicon sensors for ten exercises. We take advantage of transfer learning to strike the right balance between computation and performance. We propose a convolutional neural network (CNN) and train it using 117-dimensional skeletal angle displacement data from Vicon. This pre-trained convolutional neural network is fine-tuned for each post-stroke exercise movement. We use the publicly available rehabilitation exercise dataset to showcase the effectiveness and efficacy of our proposed simple CNN model. Our pretrained CNN model outperforms existing state-of-the-art complex Spatio Temporal Convolutional NN and achieves an average of 0.005795 MAD and 0.00786944 RMS error

Motor Imagery Detection Toward Non-Invasive Brainwave Based Typing

Electroencephalography (EEG) signals can be captured non-invasively with the help of Brain-Computer Interfaces (BCI). These EEG signals contain many essential information that can serve a great purpose when used correctly. By the appropriate interpretation of this EEG signal, we can provide people with limited ability to perform certain actions which they are unable to do due to their current condition. Paralyzed and semi-paralyzed people who are often found struggling to express themselves due to their medical condition can greatly benefit from the application of EEG. Typing or writing a letter requires functional motor movement. If we can detect the motor imagery movement from the EEG signal and determine the intent of the subject who is unable to perform motor functions but is imagining them, we can apply it to determine what they are trying to express in typed textual format. However, extracting features from EEG signals is incredibly challenging as EEG is susceptible to noise. Due to the absence of any informative association between the signals and the activity of the brain detecting motor movements and classifying them is difficult. Deep neural networks are proficient in understanding complicated features and performing computation which is very demanding. In this paper, we utilize the potential of deep neural networks to develop a model which is able to identify the motor imagery movement from the EEG signal of a subject. We envision to use this motor imagery obtained from the non-invasive brainwave to move the cursor using user thought to write letters and form words

On theories of enhanced CP violation in B_s,d meson mixing

The DO collaboration has measured a deviation from the standard model (SM) prediction in the like sign dimuon asymmetry in semileptonic b decay with a significance of 3.2 sigma. We discuss how minimal flavour violating (MFV) models with multiple scalar representations can lead to this deviation through tree level exchanges of new MFV scalars. We review how the two scalar doublet model can accommodate this result and discuss some of its phenomenology. Limits on electric dipole moments suggest that in this model the coupling of the charged scalar to the right handed u-type quarks is suppressed while its coupling to the d-type right handed quarks must be enhanced. We construct an extension of the MFV two scalar doublet model where this occurs naturally.Comment: 10 pages, 7 figures, v3 final JHEP versio

Decays of ℓ=1\ell=1 Baryons --- Quark Model versus Large-NcN_c

We study nonleptonic decays of the orbitally excited, \su6 \rep{70}-plet baryons in order to test the hypothesis that the successes of the nonrelativistic quark model have a natural explanation in the large-$N_c$ limit of QCD. By working in a Hartree approximation, we isolate a specific set of operators that contribute to the observed s- and d-wave decays in leading order in $1/N_c$. We fit our results to the current experimental decay data, and make predictions for a number of allowed but unobserved modes. Our tentative conclusion is that there is more to the nonrelativistic quark model of baryons than large-$N_c$.Comment: LaTeX 49pp. (38 pp. landscape), PicTex, PrePicTex, PostPicTex required for 3 figures, Harvard Preprint HUTP-94/A008. (Two additional operators are included, but conclusions are unchanged.

Locality in Theory Space

Locality is a guiding principle for constructing realistic quantum field theories. Compactified theories offer an interesting context in which to think about locality, since interactions can be nonlocal in the compact directions while still being local in the extended ones. In this paper, we study locality in "theory space", four-dimensional Lagrangians which are dimensional deconstructions of five-dimensional Yang-Mills. In explicit ultraviolet (UV) completions, one can understand the origin of theory space locality by the irrelevance of nonlocal operators. From an infrared (IR) point of view, though, theory space locality does not appear to be a special property, since the lowest-lying Kaluza-Klein (KK) modes are simply described by a gauged nonlinear sigma model, and locality imposes seemingly arbitrary constraints on the KK spectrum and interactions. We argue that these constraints are nevertheless important from an IR perspective, since they affect the four-dimensional cutoff of the theory where high energy scattering hits strong coupling. Intriguingly, we find that maximizing this cutoff scale implies five-dimensional locality. In this way, theory space locality is correlated with weak coupling in the IR, independent of UV considerations. We briefly comment on other scenarios where maximizing the cutoff scale yields interesting physics, including theory space descriptions of QCD and deconstructions of anti-de Sitter space.Comment: 40 pages, 11 figures; v2: references and clarifications added; v3: version accepted by JHE

Order alpha^3 ln(1/alpha) Corrections to Positronium Decays

The logarithmically enhanced alpha^3 ln(1/alpha) corrections to the para- and orthopositronium decay widths are calculated in the framework of dimensionally regularized nonrelativistic quantum electrodynamics.In the case of parapositronium, the correction is negative, approximately doubles the effect of the leading logarithmic alpha^3 ln^2(1/alpha) one, and is comparable to the nonlogarithmic O(alpha^2) one. As for orthopositronium, the correction is positive and almost cancels the alpha^3 ln^2(1/alpha) one. The uncertainties in the theoretical predictions for the decay widths are reduced.Comment: 10 pages (Latex); missing term added, corrected coefficient B_p used, numerical results insignificantly change

New Physics Models of Direct CP Violation in Charm Decays

In view of the recent LHCb measurement of Delta A_CP, the difference between the time-integrated CP asymmetries in D --> K+K- and D --> pi+pi- decays, we perform a comparative study of the possible impact of New Physics degrees of freedom on the direct CP asymmetries in singly Cabibbo suppressed D meson decays. We systematically discuss scenarios with a minimal set of new degrees of freedom that have renormalizable couplings to the SM particles and that are heavy enough such that their effects on the D meson decays can be described by local operators. We take into account both constraints from low energy flavor observables, in particular D0-D0bar mixing, and from direct searches. While models that explain the large measured value for Delta A_CP with chirally enhanced chromomagnetic penguins are least constrained, we identify a few viable models that contribute to the D meson decays at tree level or through loop induced QCD penguins. We emphasize that such models motivate direct searches at the LHC.Comment: 24 pages, 13 figures. v2: typos corrected, reference added, published versio