Miracle-dz/UniFAR-FTUs huggingface dataset:
A Wideband Single-Fed, Circularly-Polarized Patch Antenna With Enhanced Axial Ratio Bandwidth for UHF RFID Reader Applications

A wideband single-fed, circularly-polarized patch antenna with enhanced axial ratio bandwidth for RFID reader application is proposed. The antenna consists of a modified half E-shaped patch, a near-field resonant parasitic (NFRP) patch, and four rotated vertical metallic plates on the ground plane. The metallic plates surrounding the main radiator of the modified half E-shaped patch antenna are fabricated vertically on the ground plane. The operating frequency of the antenna decreases substantially with the vertical metallic plates, which is important for miniaturization of RFID applications. With an elliptical slot and a cut on the modified half E-shaped patch, antenna impedance bandwidth and CP performance both improve. A truncated corner patch as an NFRP element can generate an additional CP radiation mode and further enhances the axial ratio and impedance bandwidth. The measured results show that the antenna has an impedance bandwidth of 14.2% (833–960 MHz), a 3-dB AR bandwidth of 9.0% (846–926 MHz), and an average gain of 7.3 dBic over a 3-dB AR bandwidth. The proposed antenna has a compact size and a low profile ( $0.45\lambda _{0}\times 0.45\lambda _{0}\times 0.074\lambda _{0}$ ).
Method for the Absolute Calibration of Direct-Current Current Transducers

This paper describes an absolute method for calibrating commercial 1000:1 DC current transducers (DCCTs). By adding two auxiliary windings to produce 10:1 and 100:1 ratios, we use a three-step build-up method to establish the 1000:1 current ratio standard. First, we determine the 10:1 ratios of 11 DCCTs through permutation; second, we set up a two-stage composite DCCT to produce a 100:1 ratio; after switching auxiliary windings in the two-stage setup, we then derive the 1000:1 current ratio. The experimental results will be presented during the conference.
The association between awkward working posture and low back disorders in farmers: a systematic review

ABSTRACT Background: Low back disorders (LBD) are the most common musculoskeletal problem among farmers, with higher prevalence than other occupations. Although studies of the general population have shown an association between LBD and awkward working posture, farmers have unique work context and exposures that may modify this relationship. This review aimed to 1) identify published research studies investigating posture as a risk factor for LBD in farmers/agricultural workers, and 2) determine the strength of the relationship between postural exposure and LBD risk of bias assessment. Method: Comprehensive electronic searches of Medline, Web of Science, CINAHL, SCOPUS, PubMed, and EMBASE were carried out with combined conceptual groups of search terms for ‘farming’ and ‘LBD. ’ After screening, data were extracted to summarize the study design, sample characteristics, exposure assessment methods, LBD risk factors, demographic information, data collection methods, farm commodities, job context, and sampling strategy. Data were synthesized to determine the weight of evidence for awkward working posture as a risk factor for LBD among farmers. Results: Nine studies were included in this review. All studies used self-report; there were no field-based studies including direct measurement of awkward posture. There was diversity in exposure definition, exposure assessment, LBD definition, worker characteristics, and analytical approaches. There was evidence to support association between awkward working posture and LBD among farmers. Conclusion: Despite the diversity, the weight of evidence supported a relationship between awkward posture and LBD. Well-designed epidemiological studies with quantitative physical workload assessments, consistent and valid LBD definitions, and longitudinal designs are recommended to clarify the relationship between awkward posture and LBD.
Time domain analysis of incident field coupling to a microwave circuit: FDTD approach & PSpice validation

This article is devoted to a transient analysis of field-to-line coupling model. This one is a microstrip multiconductor transmission line (MTL), which can be uniform or not and connected with several loads either linear as a resistance, nonlinear like a diode or complex nonlinear as a Metal Semiconductor Field-Effect Transistor (MESFET). The finite difference time-domain technique (FDTD) is used to compute the expression of voltage and current at the line. The primary advantage of this method over many existing methods is that nonlinear terminations may be readily incorporated into the algorithm and the analysis. The numerical predictions are compared those obtained by using PSpice Software. The agreement between the both results are generally good.
A New Data Embedding Method with a New Data Embedding Domain for JPEG Images

Data embedding for digital images is a kind of technology which embeds message, i.e., data stream, into image(s). The design of data embedding may vary according to different applications such as watermarking, data hiding, authentication, steganography, etc. However, the basis of data embedding is the embedding domain. In this paper, we discover a new embedding domain, rounding/truncation error (RTE) domain, which is obtained due to the rounding/truncation error during the decompression of JPEG image, for JPEG image data embedding. To demonstrate the viability of the domain, we propose a new data embedding method which could be exploited for data hiding and authentication. Experimental results indicate that the proposed data embedding method possesses certain embedding capacity and achieves excellent performance when considering imperceptibility of the embedded image,
Cross-Lagged Relations Between Exercise Capacity and Psychological Distress During Cardiac Rehabilitation.

Background Poorer mental health is associated with lower exercise capacity, above and beyond the effect of other cardiovascular risk factors. However, the directionality of this relationship remains unclear. Purpose The main aim of the present study was to clarify, with a cross-lagged panel design, the relationship between psychological status and exercise capacity among patients in a cardiac rehabilitation (CR) program. Methods A clinical sample of 212 CR patients completed exercise-capacity testing and measures of depression and anxiety (Hospital Anxiety and Depression Scale) pre-CR and post-CR. Demographic and clinical data, including BMI and smoking history, were also collected. Multivariate stepwise regression analysis was performed to identify the best predictors of exercise capacity at discharge. Structural equation modeling was utilized to quantify the cross-lagged effect between exercise capacity and psychological distress. Results Multivariate regression analysis revealed that higher levels of psychological distress pre-CR are predictively associated with less improvement in exercise capacity post-CR, beyond the effects of age, sex, and baseline functional status. Results from structural equation modeling supported a 1-direction association, with psychological distress pre-CR predicting lower exercise capacity post-CR over and above autoregressive effects. Conclusions Study results did not support the hypothesis of a bidirectional relationship between psychological distress and EC. High levels of psychological distress pre-CR appeared to be longitudinally associated with lower exercise capacity post-CR, but not vice versa. This finding highlights the importance of assessing and treating both anxiety and depression in the early phase of secondary prevention programs.
İMALAT FİRMALARINDA AR-GE YATIRIM ORANLARI İLE İNOVASYON KAPASİTESİ İLİŞKİSİ

In today's world, companies should give importance to R & D activities in order to be able to continue their activities permanently. Companies that give importance to R & D investments will gain competitive advantage. The rate of investment in R & D activities is among the benchmarking criteria for R & D development level. For this purpose, the R & D investments that we consider the most important in Turkey by the Istanbul Chamber of Industrial Enterprises in 1000 determined each year is designated as the main body of the study. The universe of the study consists of 286 industrial companies selected from these firms. R & D investment rates and the number of R & D personnel employed by the firms in the research showed that there was a significant difference between the innovation skills and the variance analysis. As a result of the analysis, it was found that product, process and management innovation showed a significant difference according to the R & D investment rate.
ScratchDet: Exploring to Train Single-Shot Object Detectors from Scratch

Current state-of-the-art object objectors are fine-tuned from the off-the-shelf networks pretrained on large-scale classification dataset ImageNet, which incurs some additional problems: 1) The classification and detection have different degrees of sensitivity to translation, resulting in the learning objective bias; 2) The architecture is limited by the classification network, leading to the inconvenience of modification. To cope with these problems, training detectors from scratch is a feasible solution. However, the detectors trained from scratch generally perform worse than the pretrained ones, even suffer from the convergence issue in training. In this paper, we explore to train object detectors from scratch robustly. By analysing the previous work on optimization landscape, we find that one of the overlooked points in current trained-from-scratch detector is the BatchNorm. Resorting to the stable and predictable gradient brought by BatchNorm, detectors can be trained from scratch stably while keeping the favourable performance independent to the network architecture. Taking this advantage, we are able to explore various types of networks for object detection, without suffering from the poor convergence. By extensive experiments and analysis on downsampling factor, we propose the Root-ResNet backbone network, which makes full use of the information from original images. Our ScratchDet achieves the state-of-the-art accuracy on PASCAL VOC 2007, 2012 and MS COCO among all the train-from-scratch detectors and even performs better than several one-stage pretrained methods. Codes will be made publicly available at https://github.com/KimSoybean/ScratchDet
Survival Analysis within Stack Overflow: Python and R

Online Question and Answer communities, particularly Stack Overflow, can serve as helpful resources for programming professionals and enthusiasts. However, users of such services are inherently wary of the "life-time" of a question once posted. In fact, the timeframe observed between the stages where one initially poses a question to the point where a response is accepted as a satisfactory answer is posted can vary greatly between programming languages. One logical approach to determining the nature of these responses has been to collect relevant data from Stack Overflow within a set time period and apply Survival Analysis principles as a means of predicting response data related to the programming topics of R and Python. Utilizing a longitudinal design, and exploring details such as event counts, time in hours till first response, time till accepted answer, resulted in neither language excelling in every area; Python demonstrated the best overall answer rate. Whereas R demonstrated the best-accepted answer rate.
Optimization of Plasmonic-Organic Hybrid Electro-Optics

Plasmonic-organic hybrid technology affords the potential for exceptional bandwidth, extremely small footprint, and very low drive voltages resulting in substantially improved energy efficiency for devices. Optical loss is a well-recognized problem for plasmonic technologies but is currently addressed with some notable success. Thereby, the optimization of electrically poled organic electro-optic (OEO) materials is most critical since a large electro-optical coefficient allows implementation of short active device structures that result in lower insertion losses and lower voltage-length products. Most importantly, short structures also guarantee largest bandwidths and best energy efficiencies. Yet, an efficient optimization of in-device performance of OEO materials requires the development of novel computational simulation methods, especially as waveguide width dimensions reach tens of nanometers in plasmonic waveguides and as electrode surface/material interfacial effects become more and more dominant. The focus of this communication is on novel multi-scale modeling methods, including coarse-grained Monte Carlo statistical mechanical simulations combined with quantum mechanical methods to simulate and analyze the linear and nonlinear optical properties for high chromophore number density solid-state OEO materials. New chromophores are developed with the assistance of theory and may lead to an order of magnitude improvement in device performance.
Partially-Activated Conjugate Beamforming for LoS Massive MIMO Communications

A partially activated conjugate beamforming (PACB) is proposed for massive multiple-input multiple-output communications, where the line-of-sight (LoS) channel is dominant. Unlike the conventional conjugate beamforming which activates all the antenna elements to radiate the signals, our PACB activates only a fraction of the antennas by exploiting the spatial structure of LoS channel, and it can mitigate the inter-user interference more effectively, leading to dramatically enhanced downlink spectral efficiency. A low-complexity search algorithm is also introduced to calculate the optimal number of activated antennas. Theoretical analysis and simulation results both confirm that our PACB offers significantly higher downlink spectral efficiency compared to its conventional beamforming counterpart.
Do Thirty-Second Post-activation Potentiation Exercises Improve the 50-m Freestyle Sprint Performance in Adolescent Swimmers?

Objectives: The purpose of the study was to investigate performance, biomechanical, physiological, and psychophysiological effects of a simple and easily organized post-activation potentiation (PAP) re-warm-up performed before a 50-m freestyle swimming sprint. Methods: Regional level male adolescent swimmers [age: 13.0 ± 2.0 years; (min 11 years – max 15 years)] performed four trial conditions (three experimental, one control) on different days. The control trial involved a standardized 1200-m warm-up followed by 30 min of rest and a maximal 50-m freestyle swimming sprint. The experimental trials involved the same protocol but added a PAP component after a 20-min rest (10 min pre-50-m): The different PAP component involved the subjects in completing a 30-s maximal effort of: (1) push-ups (PU – upper body), (2) squats (SQ – lower body), and (3) burpees (BP – lower and upper body). Performance (time-trial), biomechanical (stroke length, stroke frequency), physiological (blood lactate concentrations, heart rate), and psychophysiological (ratings of perceived exertion) variables were collected. Results: The results demonstrated that the PAP protocols used in this investigation had no effect on swimming performance. Before the 50-m swimming sprint, the lactate values were significantly higher after the PU, BP, and SQ PAP loads compared to the control condition [P(CC-PU) = 0.02; P(CC-BP) = 0.01; P(CC-SQ) = 0.04]. For Lactate values, a significant and large effect of experimental condition compared to control condition was found (p < 0.05, η2 = 0.68). At 1 min after the 50-m time trial, significant differences were observed between the control condition and the different PAP loads [P(CC-PU) = 0.01; P(CC-BP) = 0.04; P(CC-SQ) = 0.01]. At 3 min after the 50-m sprint, significant differences were found between the control condition and the PU and SQ PAP loads [P(CC-PU) = 0.018; P(CC-SQ) = 0.008, respectively]. Additionally, a significant and large effect of experimental condition was found at 1 and 3 min after the 50-m swimming sprint (p < 0.05, η2(1 min) = 0.73; η2(3 min) = 0.59). There were medium sized but non-significant effects of interaction between the conditions, was illustrated for the mean HR values in response to the different conditions (p > 0.05; η2 = 0.083). Conclusion: None of the three PAP protocols showed any significant improvement in performance, biomechanical, physiological, and psychophysiological variables before, during and after the 50-m swimming time-trial. Further studies are warranted to investigate ways to improve swimming performance with simple body mass exercises performed in-between the end of pool warm-up and race start.
Metabolomic Markers of Phthalate Exposure in Plasma and Urine of Pregnant Women

Phthalates are known endocrine disruptors and found in almost all people with several associated adverse health outcomes reported in humans and animal models. Limited data are available on the relationship between exposure to endocrine disrupting chemicals and the human metabolome. We examined the relationship of metabolomic profiles in plasma and urine of 115 pregnant women with eleven urine phthalate metabolites measured at 26 weeks of gestation to identify potential biomarkers and relevant pathways. Targeted metabolomics was performed by selected reaction monitoring liquid chromatography and triple quadrupole mass spectrometry to measure 415 metabolites in plasma and 151 metabolites in urine samples. We have chosen metabolites with the best defined peaks for more detailed analysis (138 in plasma and 40 in urine). Relationship between urine phthalate metabolites and concurrent metabolomic markers in plasma and urine suggested potential involvement of diverse pathways including lipid, steroid, and nucleic acid metabolism and enhanced inflammatory response. Most of the correlations were positive for both urine and plasma, and further confirmed by regression and PCA analysis. However, after the FDR adjustment for multiple comparisons, only 9 urine associations remained statistically significant (q-values 0.0001–0.0451), including Nicotinamide mononucleotide, Cysteine T2, Cystine, and L-Aspartic acid. Additionally, we found negative associations of maternal pre-pregnancy body mass index (BMI) with more than 20 metabolomic markers related to lipid and amino-acid metabolism and inflammation pathways in plasma (p = 0.01–0.0004), while Mevalonic acid was positively associated (p = 0.009). Nicotinic acid, the only significant metabolite in urine, had a positive association with maternal BMI (p = 0.002). In summary, when evaluated in the context of metabolic pathways, the findings suggest enhanced lipid biogenesis, inflammation and altered nucleic acid metabolism in association with higher phthalate levels. These results provide new insights into the relationship between phthalates, common in most human populations, and metabolomics, a novel approach to exposure and health biomonitoring.
Dynamic Analysis and Improved Control Design of a Grid-Connected Converter with Flexible Multi-Sequence Reactive Current Injection

The recently developed grid codes suggest the injection of a flexible positive- and negative-sequence reactive current components proportional to the magnitude of the voltage dip to help the power system ride through the unsymmetrical faults. However, to the best of the authors’ knowledge, the detailed dynamic analysis of the grid-connected converter dynamics with the flexible positive- and negative-sequence current injection function considering the impact of the grid strength and the converter control parameters are not reported in the literature. To fill in this gap, first, a linear model of the augmented nonlinear system dynamics is developed and the small-signal stability analysis is performed on the system dynamic behaviour. Second, a new and effective model-based controller parameters design method is proposed to maintain the system stability during and after the fault with the consideration of the mutual interaction among different system controllers. Time-domain simulations validate the accuracy and the effectiveness of the developed method.
Impact of Line and Control Parameters on Droop Stability in Inverters for Distributed Generation

This paper analyzes stability conditions and design requirements for the control parameters in droop-controlled inverters. The analysis focusses on a single inverter unit with ac (output) filters and interface transformer, as this may be regarded as the elementary component of a distributed generation system. Through a process of thought simplifications and manipulations, the linearized full state-space model is transformed into a unique single-input, single-output system comprising several nested loops. The resulting analytical model in terms of transfer functions has enough “structure” to represent interactions between the different actors of the overall control, such as droop linear and derivative terms, virtual impedance, and voltage controllers. Stability conditions for the corresponding parameters are then derived analytically. Experimental tests are carried out on the complete system to check the reliability of the proposed model.
Payer Type, Race/Ethnicity, and the Timing of Surgical Management of Urinary Stone Disease.

PURPOSE Surgery for upper tract urinary stone disease is often reserved for symptomatic patients and those whose stone does not spontaneously pass after a trial of passage. Our objective was to determine whether payer type or race/ethnicity is associated with the timeliness of kidney stone surgery. MATERIALS AND METHODS A population-based cohort study was conducted using the California Office of Statewide Health Planning and Development dataset from 2010 to 2012. We identified patients who were discharged from an emergency department (ED) with a stone diagnosis and who subsequently underwent a stone surgery. Primary outcome was time from ED discharge to urinary stone surgery in days. Secondary outcomes included potential harms resulting from delayed stone surgery. RESULTS Over the study period, 15,193 patients met the inclusion criteria. Median time from ED discharge to stone surgery was 28 days. On multivariable analysis patients with Medicaid, Medicare, and self-pay coverage experienced adjusted mean increases of 46%, 42%, and 60% in time to surgery, respectively, when compared with those with private insurance. In addition, patients of Black and Hispanic race/ethnicity, respectively, experienced adjusted mean increases of 36% and 20% in time to surgery relative to their White counterparts. Before a stone surgery, underinsured patients were more likely to revisit an ED three or more times, undergo two or more CT imaging studies, and receive upper urinary tract decompression. CONCLUSIONS Underinsured and minority patients are more likely to experience a longer time to stone surgery after presenting to an ED and experience potential harm from this delay.