Miracle-dz/UniFAR-FTUs huggingface dataset:
The effect of communication and social motives on E-government services through social media groups

ABSTRACT E-government on social media has received much attention lately. Despite a recent call for further research into social interaction and communication aspects of e-government on social media, there is still limited empirical evidence regarding why individuals participate in the social aspect of e-government services and how that relates to their expectations and satisfactions. The present work addresses this gap by extending the Expectation-Confirmation Theory (ECT) to study communication and social interactions in government Facebook groups. The results show that communication quality and responsiveness are two key elements that contribute to the perceived level of usefulness. These two variables together with social interaction had a statistically significant effect on the overall confirmation of expectations. Perceived usefulness and satisfaction predict continuance use intention of e-government social networking services with satisfaction influencing such intention more than perceived usefulness. Further multi-group analyses show that generational difference and usage frequency moderates the relationships of the extended model. Managerial implications are provided.
Optimum sizing of distributed generation and storage capacity in smart households

Summary form only given. In the near future, a smart grid will accommodate customers who are prepared to invest in generation-battery systems and employ energy management systems in order to cut down on their electricity bills. The main objective of this paper is to determine the optimum capacity of a customer's distributed-generation system (such as a wind turbine) and battery within the framework of a smart grid. The proposed approach involves developing an electricity management system based on stochastic variables, such as wind speed, electricity rates, and load. Then, a hybrid stochastic method based on Monte Carlo simulation and particle swarm optimization is proposed to determine the optimum size of the wind generation-battery system. Several sensitivity analyses demonstrate the proper performance of the proposed method in different conditions.
Noise properties of microwave signals synthesized with femtosecond lasers

We discuss various aspects of high resolution measurements of phase fluctuations at microwave frequencies. This includes methods to achieve thermal noise limited sensitivity, along with the improved immunity to oscillator amplitude noise. A few prototype measurement systems were developed to measure phase fluctuations of microwave signals extracted from the optical pulse trains generated by femtosecond lasers. This enabled first reliable measurements of the excess phase noise associated with optical-to-microwave frequency division. The spectral density of the excess phase noise was found to be -140 dBc/Hz at 100 Hz offset from the 10 GHz carrier which was almost 40 dB better than that of a high quality microwave synthesizer
Inductance Mathematic Model of a Homopolar Inductor Alternator in a Novel Pulse Capacitor Charge Power Supply

The investigation of inductance mathematic model of a homopolar inductor alternator (HIA) in a novel pulse-capacitor charge power supply (CCPS) is presented. We study the characteristics of the inductance parameters based on the HIA theory and 3-D finite element analysis, establish the inductance mathematics model of HIA, and build a novel pulse-CCPS with 12/10-pole HIA. We also establish the simulation model of the power supply and compare the simulation results with the experimental one. The results prove the correctness of the inductance mathematic model. Finally, the problem of parameters-matching between the charging circuit and the HIA inductance is discussed.
Optimal Positioning of Mobile Platforms for Accurate Manipulation Operations

Many mobile robotics applications, especially in industrial environments, require the robot to perform safe navigation and then reach the goal with a high precision. In this research work, the objective is to analyze the appropriateness of autonomous natural navigation strategies for mobile manipulation tasks. The system must position itself in a realistic map, follow a path closely and then achieve an accurate positioning in the destination point in order to be able to perform the manipulation, inspection or pick task efficiently. Autonomous navigation is not able to fulfill the accuracy required by some of the jobs so that a second positioning system using vision is proposed in this paper. The experiments show that localization systems have, on average, an error greater than a decimetre and how an additional positioning system can reduce it to a few millimetres.
Stochastic Geometry Analysis of Energy Efficiency in Heterogeneous Network with Sleep Control

Deploying Pico Base Stations (PBSs) throughout a conventional Macro Base Station (MBS) layout can improve the system capacity, which also brings substantial energy consumption. Sleep control is one of the effective ways to save energy, but it may lead to the Spectral Efficiency (SE) loss. In this letter, we study the energy-SE tradeoff in heterogeneous network with sleep control where some PBSs are adaptively switched on or off based on traffic variation. Using tools from stochastic geometry and markov chain theory, we derive the analytical expressions in terms of power consumption, SE and energy efficiency. Numerical results confirm that our theoretical analysis is reasonable. Additional, our results provide new insight into the setting of threshold of the sleep control scheme.
Framing stress and associated behaviours at work

Purpose The purpose of this paper is to understand more precisely the culture and interpersonal behaviours associated with stress. Design/methodology/approach The research was conducted using a qualitative approach through an ethnographic methodology in relation to three companies. The greater part of the data collection period was structured into observations that ranged between 2 and 4 hr per day, 1–3 days per week, for a period of six months. A total of ten sites were explored; and on each site, the observations involved activities by 5–20 people. Findings The results showed the pivotal importance of interpersonal relationships in coping with the uncertainty of working conditions, the coordination of teamwork and managing responsibilities and power interactions. It was found that the impact of stress is multifaceted, affecting the physical status, interpersonal relationships, work performance and emotional well-being of construction workers. The workers who were studied emphasised five sources of support that help moderate work-related stress: additional tools such as communication systems and software, a facilitated access to professional help (e.g. psychological services), organisational changes in leadership, provision of resources for the well-being of personnel (e.g. job training) and better teamwork. Practical implications The study underlines the importance of dedicated services for stress management and specific training-related abilities devoted to reinforcing positive person–organisation dynamics. In particular, the abilities should relate to managing the impact of stress in terms of physique, interpersonal relationships, work performance and emotional well-being. Originality/value This is one of the first studies to adopt a psychological perspective for understanding construction scenarios and phenomena and was conducted by a qualified psychologist.
The Upper Paleolithic of the Americas

ABSTRACT Substantial archaeological and genetic data suggest that the initial occupation of the Americas is more complex and diverse than previously thought. As evidence for multiple patterns and/or adaptive strategies in distinct areas of the western hemisphere emerge, the terminology remains incoherent. Most terms are applied arbitrarily, incorporate “Clovis,” or refer only to single populations and not the chronological period. We argue for inclusion of “Upper Paleolithic” to any reference terminology concerning the Last Glacial Maximum occupations of the Americas. Using archaeological and genetic data as a benchmark, we assess the current chronology of this period and discuss the parallels between Old and New World technologies. We argue that the patterns in the Americas are rooted in the Old World and this term provides a connection to global archaeological patterns. The term “Upper Paleolithic” should be adopted as a terminological and chronological marker for the earliest human occupation of the Americas.
Optimum combining in digital mobile radio with cochannel interference

This paper studies optimum signal combining for space diversity reception in cellular mobile radio systems. With optimum combining, the signals received by the antennas are weighted and combined to maximize the output signal-to-interference-plus-noise ratio. Thus, with cochannel interference, space diversity is used not only to combat Rayleigh fading of the desired signal (as with maximal ratio combining) but also to reduce the power of interfering signals at the receiver. We use analytical and computer simulation techniques to determine the performance of optimum combining when the received desired and interfering signals are subject to Rayleigh fading. Results show that optimum combining is significantly better than maximal ratio combining even when the number of interferers is greater than the number of antennas. Results for typical cellular mobile radio systems show that optimum combining increases the output signal-to-interference ratio at the receiver by several decibels. Thus, systems can require fewer base station antennas and/or achieve increased channel capacity through greater frequency reuse. We also describe techniques for implementing optimum combining with least mean square (LMS) adaptive arrays.
Viscoelastic and dry-sliding wear properties of basalt fiber-reinforced composites based on a surface-modified graphene oxide/epoxy matrix

The current study focuses on the development of silanized graphene oxide reinforced basalt fiber/epoxy composites for enhanced tribological and viscoelastic properties. The modified-graphene oxide nanoplatelets were characterized using energy-dispersive X-ray spectroscopy, and Raman analyses. Pin-on-disk wear test and dynamic mechanical thermal analysis were conducted to determine the tribological and viscoelastic properties of the fabricated specimens with different silanized-graphene oxide loadings in the matrix (0–0.5 wt.% at a step of 0.1). The multiscale specimens were fabricated using the hand lay-up technique. The best silanized-graphene oxide loading for effectively enhancing the tribological properties was found to be 0.4 wt. %, whose wear rate and friction coefficient were 62% and 44%, respectively lower than those of the neat basalt/epoxy composite. The examination of the worn surfaces showed the enhanced basalt fiber/epoxy bonding in graphene oxide-reinforced specimen. From the results of dynamic mechanical thermal analysis, the specimen filled with 0.4 wt. % silanized-graphene oxide demonstrated the highest increase of 130% and 13.6℃ in the storage modulus and glass transition temperature as compared to the neat composite. This study indicated that the addition of silanized-graphene oxide considerably enhanced the tribological and viscoelastic properties of the fibrous composites.
Real-time multiple event detection and classification using moving window PCA

This paper proposes a method for the detection and classification of multiple events in an electrical power system in real-time, namely; islanding, high frequency events (loss of load), and low frequency events (loss of generation). This method is based on principal component analysis of frequency measurements and employs a moving window approach to combat the time-varying nature of power systems, thereby increasing overall situational awareness of the power system. Numerical case studies using both real data, collected from the U.K. power system, and simulated case studies, constructed using DigSilent PowerFactory, for islanding events, as well as both loss of load and generation dip events, are used to demonstrate the reliability of the proposed method.
Opaque Information, Deviation from Target Leverage and Speed of Adjustment

Information opacity leads to information asymmetry. In this situation, in providing their own financial needs, firms face limitations and inevitably provide their financial needs from the debt market by signalling private information to it. In addition, information opacity affects the leverage adjustment speed. This research investigates the effect of information opacity on deviation from target leverage and its’ adjustment speed during 2003 - 2017 in 131 firms listed in Tehran Stock Exchange. To estimate the research models, we use the regression analysis with panel data approach, the approach to control the effects of years and industries and the generalized method of moments with system estimator (system GMM). The research results show that the increase in information opacity increases (decreases) the positive (negative) deviation from target leverage. Also, research findings indicate that the increase in information opacity decreases the adjustment speed.
Novel design of triple bands EBG

This paper presents a novel design for a triple band electromagnetic band gap (EBG) structures that provides three band gaps, with operating frequency of below 10 GHz, while the ordinary mushroom like EBG structure gives only one band gap. Complexity reduction (reduce the number of unit cells and Vias) was achieved by replacing each four cells of the Mushroom like EBG by the one of double slotted type EBG (DSTEBG) or triple side slotted EBG (TSSEBG). The Mushroom like EBG was further modified by increasing its size and inserting the slots to gain more capacitance and inductance which resulted into triple band stop.The new designs wer compared with bandwidths expressed by other EBGs and -20 dB cut-off frequencies. The size of EBG element and the gap between EBG elements, and slot width were investigated to analyse their effect on the transmission response. The structures were designed from 2.54 mm Rogers RT/Duroid 6010 substrate with relative permittivity of 10.2 and loss tangent of 0.0023. Among the investigated EBGs, the single band mushroom like EBG and the triple band of the TSSEBG demonstrated better bandwidth and lower resonance frequency performance, whereas the DSTEBG showed larger bandwidth for the first and third band. The proposed EBGs could be useful in the antenna design and other microwave circuits.
My Body Looks Like That Girl’s: Body Mass Index Modulates Brain Activity during Body Image Self-Reflection among Young Women

Body image distress or body dissatisfaction is one of the most common consequences of obesity and overweight. We investigated the neural bases of body image processing in overweight and average weight young women to understand whether brain regions that were previously found to be involved in processing self-reflective, perspective and affective components of body image would show different activation between two groups. Thirteen overweight (O-W group, age = 20.31±1.70 years) and thirteen average weight (A-W group, age = 20.15±1.62 years) young women underwent functional magnetic resonance imaging while performing a body image self-reflection task. Among both groups, whole-brain analysis revealed activations of a brain network related to perceptive and affective components of body image processing. ROI analysis showed a main effect of group in ACC as well as a group by condition interaction within bilateral EBA, bilateral FBA, right IPL, bilateral DLPFC, left amygdala and left MPFC. For the A-W group, simple effect analysis revealed stronger activations in Thin-Control compared to Fat-Control condition within regions related to perceptive (including bilateral EBA, bilateral FBA, right IPL) and affective components of body image processing (including bilateral DLPFC, left amygdala), as well as self-reference (left MPFC). The O-W group only showed stronger activations in Fat-Control than in Thin-Control condition within regions related to the perceptive component of body image processing (including left EBA and left FBA). Path analysis showed that in the Fat-Thin contrast, body dissatisfaction completely mediated the group difference in brain response in left amygdala across the whole sample. Our data are the first to demonstrate differences in brain response to body pictures between average weight and overweight young females involved in a body image self-reflection task. These results provide insights for understanding the vulnerability to body image distress among overweight or obese young females.
State sensing of composite structures with complex curved surface based on distributed optical fiber sensor

Composite structures with complex curved surface are typical important external structures of aircraft. Residual strain will be formed due to complex manufacturing processes, resulting in the weakness of structural strength. In addition, there are great security implications that various mechanisms used for aircraft safety may cause failures on service, such as fiber fracture, matrix cracking, stratification, and debonding. In this article, methods of structural state sensing on composite structures with complex curved surface are researched. This article established a method of strain monitoring on composite structures and strategy of damage identification based on distributed optical fiber sensors. First, strategies of high spatial resolution strain measurement are studied, and the criteria of damage identification on composite laminates based on strain information are deduced, which could be used on accurate positioning of crack tips. Finally, strain measurement and damage identification tests of composite structures with complex curved surface under uniform load condition were conducted. The results indicate that the distributed optical fiber sensor installed on the composite structures with complex curved surface can be used to measure strain precisely and identify damage in the neighborhood of fiber installation path accurately.
The e ect of changing scores for multi-way tables with open-ended ordered categories

Log-linear models are used to analyze the contingency tables. If the variables are ordinal or interval, because the score values a ect both the model signi cance and parameter estimates, selection of score values has importance. Sometimes an interval variable contains open-ended categories as the rst or last category. While the variable has openended classes, estimates of the lowermost and/or uppermost values of distribution must be handled carefully. In that case, the unknown values of the rst and last classes can be estimated rstly, and then the score values can be calculated. In the previous studies, the unknown boundaries were estimated by using interquartile range (IQR). In this study, we suggested interdecile range (IDR), interpercentile range (IPR), and mid-distance range (MDR) as alternative to IQR to detect the e ects of score values on model parameters.
A Sensorless Commutation Error Correction Method for High-Speed BLDC Motors Based on Phase Current Integration

Inaccurate commutation in brushless dc motor (BLDCM) will induce current harmonic and increase motor loss, which reduce motor efficiency. Meanwhile, for the sensorless BLDCM, the motor commutation is seriously affected by detection errors and calculation errors, which are caused by the nonideal conditions and the parameters variation. In this paper, a novel commutation error correction method is proposed to determine optimal commutation instant for the sensorless high-speed BLDCM. First, the relationship between commutation error and motor phase current is analyzed. According to this relationship, an initial commutation error can be calculated and compensated in one conduction interval. Then, online commutation corrections are performed to compensate for the residual error in following conduction intervals. The correction accuracy of commutation instant is determined by the phase current integral difference. This method is insensitive to motor parameters and back electromotive force waveform. Therefore, the commutation error is effectively eliminated in the whole speed range. Finally, the feasibility and effectiveness of the proposed method are evaluated by experimental results.
Ground robotics in tunnels: Keys and lessons learned after 10 years of research and experiments

The work reported in this article describes the research advances and the lessons learned by the Robotics, Perception and Real‐Time group over a decade of research in the field of ground robotics in confined environments. This study has primarily focused on localization, navigation, and communications in tunnel‐like environments. As will be discussed, this type of environment presents several special characteristics that often make well‐established techniques fail. The aim is to share, in an open way, the experience, errors, and successes of this group with the robotics community so that those that work in such environments can avoid (some of) the errors made. At the very least, these findings can be readily taken into account when designing a solution, without needing to sift through the technical details found in the papers cited within this text.
Extended Kalman Filter-Based Parallel Dynamic State Estimation

There is a growing need for accurate and efficient real-time state estimation with increasing complexity, interconnection, and insertion of new devices in power systems. In this paper, a massively parallel dynamic state estimator is developed on a graphic processing unit (GPU), which is especially designed for processing large data sets. Within the massively parallel framework, a lateral two-level dynamic state estimator is proposed based on the extended Kalman filter method, utilizing both supervisory control and data acquisition, and phasor measurement unit (PMU) measurements. The measurements at the buses without PMU installations are predicted using previous data. The results of the GPU-based dynamic state estimator are compared with a multithread CPU-based code. Moreover, the effects of direct and iterative linear solvers on the state estimation algorithm are investigated. The simulation results show a total speed-up of up to 15 times for a 4992-bus system.
Teaching a Course in Mathematical Programming

Abstract Computer programming and mathematical algorithms are natural partners in the development of programming skills, logical thought, and a deeper understanding of mathematical concepts. We present the details of a course which blends the two at the sophomore level. This course is required of our mathematics majors, but attracts mathematics minors from a variety of disciplines as well. Topics from this course may also be used by those wishing to add a lab component to an existing course.