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We present a differentiable formulation of rigid-body contact dynamics for objects and robots represented as compositions of convex primitives. Existing optimization-based approaches simulating contact between convex primitives rely on a bilevel formulation that separates collision detection and contact simulation. These approaches are unreliable in realistic contact simulation scenarios because isolating the collision detection problem introduces contact location non-uniqueness. Our approach combines contact simulation and collision detection into a unified single-level optimization problem. This disambiguates the collision detection problem in a physics-informed manner. Compared to previous differentiable simulation approaches, our formulation features improved simulation robustness and a reduction in computational complexity by more than an order of magnitude. We illustrate the contact and collision differentiability on a robotic manipulation task requiring optimization-through-contact. We provide a numerically efficient implementation of our formulation in the Julia language called Silico.jl.

Hospital food hygiene plays an important role in patients’ health. Studies have proved that improper practices and lack of knowledge are major contributing factors of foodborne diseases. This study has been conducted with an aim to determine knowledge, attitude and practices of hospital kitchen staff towards safe food handling in a tertiary care teaching hospital in Pune. A cross sectional study was conducted in the central kitchen of the hospital.Data was collected from 20 food handlers (the entire staff working in the central kitchen) through a pre- validated questionnaire. Data was collected in May- June 2022. Most of food handlers had studied up till high school and their mean age group was 36.2 years. The average work experience of respondents was 16.5 years. The result of the questionnaire showed that majority of food handlers have a fair knowledge in safe food handling procedures, have a good attitude and practices. However, the results also strongly emphasize the need of more frequent food hygiene training of hospital food handlers. It also suggests that non-food handlers such as the nursing staff or kitchen supervisor should also be involved in the training. Some aspects of food handlers’ safety behaviour also needs to be emphasized.

We present a framework for bi-level trajectory optimization in which a system's dynamics are encoded as the solution to a constrained optimization problem and smooth gradients of this lower-level problem are passed to an upper-level trajectory optimizer. This optimization-based dynamics representation enables constraint handling, additional variables, and non-smooth behavior to be abstracted away from the upper-level optimizer, and allows classical unconstrained optimizers to synthesize trajectories for more complex systems. We provide a path-following method for efficient evaluation of constrained dynamics and utilize the implicit-function theorem to compute smooth gradients of this representation. We demonstrate the framework by modeling systems from locomotion, aerospace, and manipulation domains including: acrobot with joint limits, cart-pole subject to Coulomb friction, Raibert hopper, rocket landing with thrust limits, and planar-push task with optimization-based dynamics and then optimize trajectories using iterative LQR., RA-L/ICRA final submission

To compare the efficacy of tezepelumab with other approved biologics via indirect treatment comparisons (ITCs) in patients aged ≥ 12 years with severe uncontrolled asthma. Data from randomized controlled trials (RCTs) identified from a systematic literature review were synthesized using two different ITC approaches: network meta-analysis (NMA) and simulated treatment comparison (STC). Outcomes of interest were annualized asthma exacerbation rate (AAER) and AAER for exacerbations leading to hospitalization or emergency room visit. To address potential heterogeneity between study populations, various subgroup analyses were performed for the NMA (based on blood eosinophil count, fractional exhaled nitric oxide level, and presence of allergic asthma), and for the STC, models were adjusted for potential treatment effect modifiers. Sensitivity analyses were performed to assess the impact of study design (exclusion of non-placebo-controlled studies and non-phase 3 or 4 studies). Results were reported as rate ratios (RRs) with 95% credible/confidence intervals and ranking statistics were computed for the NMAs. Sixteen RCTs were included in at least one of the ITCs. All biologics (tezepelumab, dupilumab, benralizumab, mepolizumab, reslizumab, and omalizumab) had similar efficacy, with no statistically significant RRs for either exacerbation outcome; however, tezepelumab was favorably associated with numerically lower AAERs and was ranked first in the network for both types of exacerbation outcome. This trend was consistent in the subgroup and sensitivity analyses. As with the primary NMA, the STC results did not demonstrate any significant differences between biologics, but point estimates were favorable towards tezepelumab. Heterogeneity between trials was observed among eligibility criteria and clinically important patient characteristics; however, the impact on findings is expected to be low, based on consistency across analyses. Findings from both ITCs (NMA and STC) support the use of tezepelumab in a broad patient population of severe uncontrolled asthma of any phenotype.

A unique dual hexagonal-shaped radiating patch design with hybrid fractal curves (Meander and Koch) is presented for quad-band wireless applications. Initially, the antenna from 0th to 2nd iteration of hybrid fractal curves with PGP (Partial Ground Plane) is designed and investigated. Further, to get better results of the designed antenna in respect of Bandwidth (BW) and coefficient of reflection these hybrid curves are superimposed on the limited ground plane of 1st and 2nd iteration of the antenna, and the generated antennas are designated as Antenna – 1 and Antenna – 2. A comparison between both the antennas has been made and it is observed that antenna -2 shows better results in respect of improved BW and coefficient of reflection. The proposed antenna exhibits four resonant frequency bands 1.6, 4.8, 6.9, and 8.8GHz with improved corresponding impedance BW of 2.09, 1.36, 0.86, and 1.51GHz. The designed antenna is simulated and made on FR4 glass epoxy substrate with an overall size of 20×40×1.6 mm3. The fabricated proposed antenna is tested experimentally for the authentication of simulated results with experimental results and these are compatible with each other. The other performance indicators like radiation pattern, peak realized gain, and radiation efficiency are also determined for the proposed Hybrid Fractal Antenna (HFA) and all are found satisfactory. Due to the improved operational parameters, the designed HFA can be considered as a suitable applicant for distinct wireless applications in anticipated operational frequency ranges.

Over the years, there has been a revolutionary and steep gain in the interest of veganism. Nowadays, social media has become an integral element in people's lives. Users are spending more time on these platforms than before. Given the tremendous power of social media influencers on consumers and their impact on eating habits, their influence on converting consumers to veganism is intended to be studied. This work evaluates the behavior of online users in connection with their social media followings, measured through hashtag followings, and eventually compared through a community analysis.

Background. Interlocking nailing is considered a gold standard surgical treatment of mid-shaft closed diaphyseal tibial fractures. With increasing exposure of orthopaedic surgeons to radiation, we propose a solution to this health hazard through a study wherein we perform the surgery without any radiation or C-arm exposure. Material and methods. This prospective study was done at GMC Jammu from January 2017 to February 2020 and included 218 patients, with 18 patients having bilateral tibia fractures in the age group 15 to 58 years (mean of 37.6 years), including 63.7% males (n=139) and 36.3% females (n=79). The 236 extra-articular closed tibial mid-diaphyseal fractures were operated on and intramedullary tibial nailing was performed without a single C-arm exposure. Postoperative x-rays were done and reduction assessed by standard acceptable criteria. Results. Among 236 cases in which nailing was done, 227 (96%) patients were successfully distally locked, including 128 (56.3%) locked through the jig and 99 (43.6%) by “hit and trial method.” All cases met acceptability criteria set for management of tibia by nailing. Conclusions. 1.This study strengthens the proof that closed extra-articular diaphyseal fractures of the tibia can be managed by nailing without using the C-arm with excellent results. 2.The C-arm is always available for cases where distal locking could not be achieved. 3. The technique has a great role in centres with limited facilities of intra-operative radiography in emergency operation theatres.

Primary Care Medical Home (PCMH) redesign efforts are intended to enhance primary care's ability to improve population health and well-being. PCMH transformation that is focused on "high-value elements" (HVEs) for cost and utilization may improve effectiveness.The objective of this study was to determine if a focus on achieving HVEs extracted from successful primary care transformation models would reduce cost and utilization as compared with a focus on achieving PCMH quality improvement goals.A stratified, cluster randomized controlled trial with 2 arms. All practices received equal financial incentives, health information technology support, and in-person practice facilitation. Analyses consisted of multivariable modeling, adjusting for the cluster, with difference-in-difference results.Eight primary care clinics that were engaged in PCMH reform.We examined: (1) total claims payments; (2) emergency department (ED) visits; and (3) hospitalizations among patients during baseline and intervention years.In total, 16,099 patients met the inclusion criteria. Intervention clinics had significantly lower baseline ED visits (P=0.02) and claims paid (P=0.01). Difference-in-difference showed a decrease in ED visits greater in control than intervention (ED per 1000 patients: +56; 95% confidence interval: +96, +15) with a trend towards decreased hospitalizations in intervention (-15; 95% confidence interval: -52, +21). Costs were not different. In modeling monthly outcome means, the generalized linear mixed model showed significant differences for hospitalizations during the intervention year (P=0.03).The trial had a trend of decreasing hospitalizations, increased ED visits, and no change in costs in the HVE versus quality improvement arms.

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) claimed over 4 million lives by July 2021 and continues to pose a serious public health threat.ObjectivesOur retrospective study utilized respiratory pathogen panel (RPP) results in patients with SARS-CoV-2 to determine if coinfection (i.e. SARS-CoV-2 positivity with an additional respiratory virus) was associated with more severe presentation and outcomes.MethodsAll patients with negative influenza/respiratory syncytial virus testing who underwent RPP testing within 7 days of a positive SARS-CoV-2 test at a large, academic medical centre in New York were examined. Patients positive for SARS-CoV-2 with a negative RPP were compared with patients positive for SARS-CoV-2 and positive for a virus by RPP in terms of biomarkers, oxygen requirements and severe COVID-19 outcome, as defined by mechanical ventilation or death within 30 days.ResultsOf the 306 SARS-CoV-2-positive patients with RPP testing, 14 (4.6%) were positive for a non-influenza virus (coinfected). Compared with the coinfected group, patients positive for SARS-CoV-2 with a negative RPP had higher inflammatory markers and were significantly more likely to be admitted (P = 0.01). Severe COVID-19 outcome occurred in 111 (36.3%) patients in the SARS-CoV-2-only group and 3 (21.4%) patients in the coinfected group (P = 0.24).ConclusionsPatients infected with SARS-CoV-2 along with a non-influenza respiratory virus had less severe disease on presentation and were more likely to be admitted—but did not have more severe outcomes—than those infected with SARS-CoV-2 alone.

Background. Dry eye disease (DED) is a multifactorial and one of the most common problems treated in an ophthalmic outpatient clinic. Due to the variability in presentation, diagnosis of DED consists of a combination of subjective and objective clinical tests. The purpose of this study was to assess the effectiveness of a handheld smartphone-based infrared thermal (IRT) camera for screening symptomatic evaporative DED. Methods. This observational sex-matched control study assessed IRT images of 184 right eyes (46 normal and 138 DED) of 184 participants. Evaporative DED was assessed using noninvasive tear breakup time, fluorescein staining, and the Chinese version of the ocular surface disease index (C-OSDI) questionnaire and categorized into their respective dry eye symptomology group (none, mild, moderate, or severe). The ocular surface temperature (OST) at 8 anatomical regions of interest (ROI) (nasal conjunctiva, nasal limbus, nasal cornea, central cornea, inferior cornea, temporal limbus, temporal cornea, and temporal conjunctiva) were measured and compared using a handheld smartphone-based IRT camera. The effectiveness of these 8 ROIs OST in detecting varying severity of DED was evaluated in terms of correlations with severity of DED and their area under the curve (AUC). Results. OST at the 8 anatomical ROI was significantly higher in DED participants than in the non-DED group ( p < 0.05 ) except for inferior cornea, temporal limbus, and temporal conjunctival regions (>0.05). Analyzing 8 anatomical ROIs revealed that the nasal limbus had the highest Pearson correlation with the severity of DED (0.64, p < 0.001 ). Additionally, the nasal limbus ROI achieved the highest AUC of 0.79 (CI: 0.73–0.85; p < 0.05 ), sensitivity, and specificity (0.96 and 0.91) when comparing its ability to discriminated DED vs. non-DED eyes. Conclusions. Rather than a diagnostic tool, handheld smartphone-based IRT images can be considered as a rapid, noninvasive, and hygienic screening tool in discriminating DED and non-DED and potentially alleviating inconvenience experienced during conventional tests.

This paper presents the unique structure of a hybrid antenna with a blend of Peano–Gosper, Koch and Minkowski curves using a modified partial ground plane for multi-standard wireless applications. ...

Background. Glenohumeral joint arthrodesis has become a rare entity due to the introduction of shoulder arthroplasty. It is an excellent salvage procedure for patients with severe shoulder dysfunction, with limited treatment options, indicated for brachial plexus injury, tumour resection, chronic infection, failed prosthetic arthroplasty, or pseudoparalysis of the shoulder due to combined rotator cuff and deltoid deficiency. Shoulder arthrodesis relieves the patient of pain and gives a decent amount of function. The aim of this study was to examine the mid-term outcomes of glenohumeral arthrodesis with 2 pelvic recon plates. Methods and methods. This study was done in a tertiary referral centre over a period of about 2 years. All the patients were operated on with 2AO 3.5mm recon plates and screws. Indications for surgery comprised unreconstructable rotator cuff tears, a neoplastic lesion, paralytic disorders, TB shoulder, arthritic disease unsuitable for arthroplasty, and sequelae of septic shoulder. Cancellous grafts were used in all operated patients, while a cortical graft was used in the tumour case to fill the bone defect after tumour excision. A minimum of 18 months was essential for inclusion into the study. Results. 15 patients were included in the study. All the patients had decreased postoperative pain, which further decreased to pain-free status at further follow-up visits. All the arthrodeses produced bony union with average time to union of 5.4 months. All patients could feed and dress themselves with the ipsilateral limb. The only complication noted in this series was a superficial infection in 3 patients only, which subsided after wound wash, debridement and antibiotics for 10 days. Conclusions. 1. With specific indications, shoulder arthrodesis results in a good painless postoperative shoulder function and thus presents an excellent operative option. 2. The position of arthrodesis chosen here ensures that the arm rests comfortably at the side. 3. The patients can move their hands to their mouth and facial regions. 4. Recon plates should be used for arthrodesis because they are easy to shape without compromising on strength. 5. Few complications of procedure are there but it is a great therapeutic measure in selected individuals.

The metamaterial inspired low-cost diamond-shaped fractal antenna (DSFA) based on edge-coupled (EC) parasitic split ring resonator (SRR) for multiband wireless application is presented and investig...

The purpose of this paper is to examine service quality constructs which leads to student satisfaction in the setting of Indian higher management education institutes. In this study, researchers ma...

Duplex stainless steels (DSSs) are prone to formation of various secondary phases in their microstructure upon exposure to high temperatures which can lead to degradation in their engineering performance. The present work was aimed to study the effect of a wide range of isothermal treatments (475°–1050 °C) on the impact toughness and corrosion resistance besides microstructure, ferrite content and microhardness of gas tungsten arc (GTA) welded 2205 DSS. It was observed that the isothermal exposure at 850 °C for 2 h led to maximum ferrite content reduction, imparted maximum hardening, caused maximum embrittlement of the weld metal (203 J → 2 J) and HAZ (204 J → 3 J) regions of the weldment besides causing maximum degradation in the pitting corrosion resistance. Corresponding to the aging condition of 475 °C/20 h, reduction in the ferrite content was not much, however, a significant increase in the microhardness along with severe loss in the toughness of the weld metal (203 J → 6 J) occurred, but the HAZ region was relatively tolerant (204 J → 54 J) against loss of toughness. In general, impact and corrosion properties were highly sensitive to degradation at 850 °C. Hence it can be inferred that the amount of ferrite content reduction cannot be directly correlated with the extent of hardening, decrease in the toughness and corrosion resistance; as such, changes will be primarily governed by the type of secondary precipitation which is temperature and exposure duration-dependent in the case of DSS welds.

Head and neck cancers (HNC) are extremely aggressive, highly recurrent, and the sixth most common cancer worldwide. Neuropeptide substance P, along with its primary receptor, neurokinin-1 (NK-1R), is overexpressed in HNC and is a central player in inflammation and growth and metastasis of several cancers. However, the precise SP-mediated signaling that promotes HNC progression remains ill defined. Using a panel of HNC lines, in this study, we investigated the effects of SP on proliferation and migration of HNC. Tumor cells were also treated with SP and alterations in inflammatory cytokines and chemokines, and their cognate receptors were analyzed by real-time PCR. Furthermore, we investigated the role of SP in inducing epithelial-mesenchymal transition (EMT), and matrix metalloproteases that promote tumor invasion. Our results showed that SP significantly increased tumor cell proliferation and migration and induced the expression of several genes that promote tumor growth, invasion, and metastasis which was suppressed by a specific NK1R antagonist L-703606. SP also activated NFκB that was suppressed on inhibiting NK1R. Collectively, our data shows that SP-NK1R-mediated inflammatory signaling comprises an important signaling axis in promoting HNC and may prove to be effective clinical target against HNC cells that are resistant to traditional therapy.

This article develops a new closed-form analytical solution to the harmonic spectrum of the pulsewidth modulated (PWM) output voltage of the single-phase inverter connected to the dc bus with considerable voltage ripple. The solution is based on a double Fourier series expansion in two variables. As the single-phase inverter forms the basic building block of most converters, the developed expressions can be applied to various topologies. This article first identifies the interactions of a single-frequency sinusoidal modulation signal and the carrier signal with the dc bus voltage harmonics. The dc bus voltage harmonics are constrained in this article to multiples of the inverter output voltage fundamental frequency. The analysis is then extended to include a multifrequency modulation signal. Starting from the general solution, new expressions for the output voltage harmonics of the modular multilevel converter (MMC) are developed. The low-capacitance MMC is chosen in this analysis due to inherent low-frequency voltage oscillations in the converter internal capacitors. The MMC analytical harmonic spectrum can incorporate the effects of the circulating current control and third harmonic injection PWM, by including the second- and third-order harmonic components in the modulation signal, respectively. The MMC analytical harmonic spectrum is benchmarked against the experimental results.

With technological advancements, the availability of low-cost smartphones and internet connectivity, the online retail industry has gained traction. A pandemic-related lockdown has fuelled the fire. Consequently, it becomes important to identify the factors defining online retail service quality (ORSQ), which affect customer satisfaction and customer engagement behaviour. First, a qualitative study was conducted to identify ORSQ factors and reliability, ease of use, customer-friendly policies, problem handling and security were found to be the most vital ones for Indian consumers. Further, a quantitative study was attempted to determine the impact of ORSQ factors on consumer satisfaction and customer engagement behaviour. While testing these relationships, website familiarity was considered as a moderating variable between ORSQ factors and customer satisfaction. The findings of the study suggest that the identified ORSQ factors influence customer satisfaction and customer engagement behaviour in turn. The moderating effect of website familiarity was also established on customer satisfaction. For the analysis, Smart PLS 3.0 was used.

The design, simulation and testing of an impulse magnetizer and the in-situ post-assembly magnetization of a permanent magnet (PM) rotor manufactured by a cold spray additive manufacturing (AM) using the prototyped magnetizer is presented in this paper. A software based finite element simulation is done to obtain the level of magnetization current required. An impulse magnetizer is built for this specification. A 4-pole rotor with cold-sprayed rectangular magnets is magnetized in this work after assembling it in the stator. Various stator terminal connection configurations are analyzed. The machine is magnetized and the back-EMF waveform and the rotor magnetization profile is obtained., IECON 2021: 47th Annual Conference of the IEEE Industrial Electronics Society, October 13-16, 2021, Toronto, ON, Canada

The permanent magnet (PM) traction motor is one of the feasible solutions to the energy crisis and environmental pollution. Due to the high demands in power and torque density with overall high efficiency, the permanent magnet synchronous machine (PMSM) is mainly considered. Usage of soft magnetic composites (SMC) material in the machine parts helps to build a complex 3D structure and reduces the manufacturing cost. This paper presents the electromagnetic performance comparison analysis of a 7.12 kW radial flux PMSM with laminated steel and SMC stator core. Two different designs of 24/20 slot-pole and 12/8 slot-pole configuration using conventional surface permanent magnet rotor design are simulated using a 3D FEA software package. The comparison is mainly focused on the torque density, copper loss, core loss, and active weight of the machine. In addition, the ring-type Halbach-array PM rotor fabricated using cold spray additive manufacturing for 12/8 slot-pole is analyzed and optimized with the SMC stator core for high-speed electric vehicle application. The THD in phase back EMF and torque ripple is reduced by modifying the SMC stator tooth shape. Also, a scaled-down laboratory design of ring-type Halbach-array PM rotor with 12/10 slot-pole is simulated using FEA with different lamination thickness of rotor core.

This paper analyzes the impact of Soft Magnetic Composite (SMC) material properties on the losses and efficiency of electrical machines and presents a method for SMC grade selection. Three electric machines are simulated using 3D Finite Element Analysis (FEA): radial flux, axial flux and transverse flux Permanent Magnet (PM) machines. The core losses in SMC parts are calculated using a hybrid method that includes the joule loss of the induced 3D eddy currents in the SMC stator core as well as geometry-independent losses calculated by analytical equations based on toroid tester data. The results show that the selection of SMC material solely based on one given material property such as, permeability, core loss or resistivity results in suboptimal motor performance. On the other hand, the simulation results show that an SMC material with balanced properties achieved the highest efficiency and best overall performance. Finally, an SMC core with balanced properties was developed and tested in a toroidal measurement setup., 2021 IEEE Energy Conversion Congress and Exposition (ECCE), October 10-14, 2021, Vancouver, BC, Canada

Developments in the field of circuit design and computer architecture have introduced a variety of architectures such as in-memory compute, near-memory compute, FPGA, CGRA, DSP, GPU and many more still in the research phase. There is an increasing need for a unifying architectural efficiency metric that is applicable during the architecture design phase as well as post-silicon benchmarking, which quantifies different architectures, and is independent of the underlying implementation technology. This paper introduces an architectural efficiency metric that satisfies the above mentioned criteria. The metric quantifies the number of instructions or the size of reconfiguration bits required to perform a computation over a range of program sizes in the architecture. The metric helps understand limitations and benefits of different architectures, and provides insight into theoretical throughput. Our efficiency metric also informs the user/compiler about hardware options in a multi-architecture system based on the size of computation required.

Background Within the United States (US), because racial/ethnic disparities in cannabis arrests continue, and cannabis legalization is expanding, understanding disparities in availability of legal cannabis services is important. Few studies report mixed findings regarding disparities in availability of legal cannabis services; none examined New York. We examined disparities in availability of medical cannabis services in New York. We hypothesized that New York census tracts with few Black or Hispanic residents, high incomes, high education levels, and greater urbanicity would have more medical cannabis services. Methods In this cross-sectional study, we used data from the 2018 US Census Bureau 5-year American Community Survey and New York Medical Marijuana Program. Main exposures were census tract characteristics, including urban–rural classification, percentage of Black and Hispanic residents, percentage of residents with bachelor’s degrees or higher, and median household income. Main outcomes were presence of at least one medical cannabis certifying provider and dispensary in each census tract. To compare census tracts’ characteristics with (vs. without) certifying providers and dispensaries, we used chi-square tests and t-tests. To examine characteristics independently associated with (vs. without) certifying providers, we used multivariable logistic regression. Results Of 4858 New York census tracts, 1073 (22.1%) had medical cannabis certifying providers and 37 (0.8%) had dispensaries. Compared to urban census tracts, suburban census tracts were 62% less likely to have at least one certifying provider (aOR = 0.38; 95% CI = 0.25–0.57). For every 10% increase in the proportion of Black residents, a census tract was 5% less likely to have at least one certifying provider (aOR = 0.95; 95% CI = 0.92–0.99). For every 10% increase in the proportion of residents with bachelor’s degrees or higher, a census tract was 30% more likely to have at least one certifying provider (aOR = 1.30; 95% CI = 1.21–1.38). Census tracts with (vs. without) dispensaries were more likely to have a higher percentage of residents with bachelor’s degrees or higher (43.7% vs. 34.1%, p Conclusions In New York, medical cannabis services are least available in neighborhoods with Black residents and most available in urban neighborhoods with highly educated residents. Benefits of legal cannabis must be shared by communities disproportionately harmed by illegal cannabis.

Demographic indices known as the age-heaping indexes were used to explore the patterns of age misreporting in a multicentric survey.The data of 3252 individuals were analyzed, and measurement of errors in age for the sampled data has been evaluated by Whipple's Index (WI), Myer's Blended Index, and United Nations Age-Sex Accuracy Score which comprises Sex Ratio Score, Male Age Ratio Score (ARS), and Female ARS.Out of total 3252 participants, 828 (25.5%) were female. The mean statistical division age of our population was 34 (8.5) years and ranged from 15 to 65 years. The percentage of female ages ending with digits 0 or 5 is 23.55% and percentage of male ages ending with digits 0 or 5 is 23.28%. The calculated WI was 117.75 and 116.34 for males and females, respectively. The calculated Myer's Index for females and males is 10.53 and 25, respectively.The study provides evidence that probably age-heaping bias is less of problem in the conducted study.

This article presents a microstrip-fed octagonal shaped monopole antenna with dual band notched characteristics for UWB applications. Partial ground plane has been employed in the geometry of proposed antenna to improve the VSWR bandwidth over the entire range of UWB (3.1–10.6 GHz). Initially, the proposed antenna exhibits the VSWR bandwidth of 9.06 GHz (121.28%) with a frequency range of 2.94–12.0 GHz and after introducing C-shaped slot and complementary split ring resonator on the geometry of octagonal shaped radiating patch, dual band notched function has been acquired at Wi-MAX (3.5 GHz) and upper WLAN (5.8 GHz) frequency bands. The overall dimensions of proposed UWB antenna are 30 mm × 30 mm. The proposed antenna is designed and simulated using Ansys HFSS V13 simulator, its fabricated prototype is also tested to validate the simulated results with experimental ones. Both the results are in reasonable agreement with each other. An experimental result also reveals that the proposed antenna depicts nearly omni-directional pattern like dipole antenna.

In this manuscript, the design of double split labyrinth resonator (DSLR)-based Coplanar waveguide (CPW)-fed hybrid fractal antennas has been presented for distinct wireless applications. T...

This paper presents the design of fidget spinner-shaped antenna (FSSA) loaded with parasitic EC-SRR (edge coupled-split ring resonator) for multi-standard wireless applications. Parasitic EC-SRR el...

This paper presents the design of fractal antenna array with eight elements for multiband applications, such as WiMax (3.3–3.7 GHz), WLAN (4.82–5.95 GHz), X-band for satellite communication (7.1–7.76 GHz) and point-to-point (5.92–8.5 GHz) for high-speed wireless communication. Each element of array is separated by λ/2 distance. FR4 glass epoxy substrate with dielectric constant 4.4 and thickness of 1.6 mm is used for the designing of the proposed antenna array. ANSYS/ANSOFT HFSS V13 software is used for designing and simulating the proposed antenna. Different parameters like gain, radiation pattern and reflection coefficient are obtained at all frequencies in the range of 3 to 10 GHz. It is observed that the proposed antenna array works on eight different frequencies, whereas conventional antenna array works at seven frequencies. The three iterations of the proposed antenna array are fabricated and tested using VNA (vector network analyzer). The experimental and simulated results are compared, and both are in good agreement with each other. Measured results of the proposed antenna array are also compared with the results of antenna array present in the literature, and it is found that the proposed antenna array operates on eight frequency bands, whereas the antenna array in the literature operates on at most three frequency bands.

Gearless and compact motors operating at high speeds (above 10 000 r/min) are increasingly being used in many fields. This paper presents the design and analysis of a coreless axial-flux permanent-magnet motor for high-speed, low-power applications. The proposed motor is designed to rotate at a speed of 30 000 r/min. To ensure the reliability of the motor at high speeds, it is essential to minimize torque ripple and the magnetic attraction between the stator and the rotor in the axial direction. Therefore, in this paper, a novel coreless stator design using multilayer printed circuit board (PCB) is proposed. The PCB stator ensures uniform distribution of the phase windings, which minimizes harmonics in the back EMF of the motor. The multilayer PCB stator makes the motor highly compact, efficient, and reliable. To improve the air-gap flux density in the coreless design, a lightweight Halbach-array based rotor is used and the Halbach magnets are covered with a high-strength nonmagnetic material to achieve high rotor integrity. MagNet 3-D and COMSOL Multiphysics are used for the finite element analysis and optimization of the motor and the simulation results are presented. A prototype of the motor is fabricated and tested with sensorless field oriented control to validate the simulation results. The back EMF obtained for the prototype is sinusoidal and its performance characteristics ensure efficient and reliable performance at high speeds.