Miracle-dz/UniFAR-FTUs huggingface dataset:
Four‐element microstrip array with polarization diversity

A four‐element microstrip antenna array excited with a tunable feeding network is described.The feeding network is composed of three quasi‐lumped couplers and a 90° phase delay line. By controlling one dc bias, the network can provide the same amplitude and two different phase combinations, including (0°, 0°, 180°, 180°) and (0°, 90°, 180, 270°), for the four array elements. With the tunable feeding network, the excitation method of the array can be switched between sequentially rotated feed mechanism and differential‐feed mechanism. A reconfigurable array prototype is constructed. Experimental results show that the array has a broadside radiation and it can provide good linear and circular polarization performances at one frequency. Simulated results are also provided to validate the designs of the microstrip antenna array with switchable polarization. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1653–1657, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27660
A Fast BP Algorithm and its Application in China Stock Market

Aiming at the drawback of large calculation and slow convergent speed in BP algorithm, this paper proposes a new BP algorithm with the concept of error deviation rate. By carrying out serious methmatical deduction, the paper revises the the chain rule of traditional BP algorithm and proves its theoretical feasibility. Then, this paper applies it to Chinese stock market and has gained quite well convergent speed and predicting effect, consequently proving the new method’s effectiveness.
Wavelet-based relay agent for isolating faulty sections in distribution grids with distributed generators

This paper presents an agent based protection scheme to detect and isolate the faults in a distribution system with high penetration of distributed generation. An algorithm that uses wavelet coefficients of the transient fault currents is proposed for the identification of faulted sections. The algorithm is a hybrid of two techniques: one that determines the direction of fault currents based on the sign of wavelet coefficients and the other that estimates the distance to a fault based on the time interval between the travelling waves (and their reflections) arriving from the fault. Studies with a simulated distribution system indicate that the proposed method can correctly recognize the faulty sections.
Iterative registration of 3D LADAR data for autonomous navigation

This paper describes an iterative algorithm for registration of 3D LADAR data. The proposed approach is iconic in nature with suitable modifications to deal with false/spurious matches, occlusions and outliers. Experimental results using data obtained from field trials on an experimental unmanned vehicle (XUV) are presented to demonstrate the efficacy of the approach. The paper also details ongoing research efforts to determine the feasibility of employing the algorithm for real-time autonomous navigation.
Design of a low phase distortion GaAs FET power limiter

A simple design technique for a GaAs FET limiter exhibiting minimum phase distortion is presented. The key idea in removing phase distortion by selecting an appropriate device and designing a bias circuit is based on the observed properties of the gate barrier under large-signal conditions. Some illustrative examples and simulation results are presented. The proposed technique is suitable for monolithic microwave integrated circuit (MMIC) design. >
Jump starting 42V powernet vehicles

The automotive industry today is faced with ever increasing electrical power demands that are stretching the capabilities of present on-board power supplies. The use of electrical and electronic features to enhance customer comfort, convenience and safety, such as electronic automatic climate control, entertainment systems, antilock brakes (ABS) and traction control (TC) systems, contribute to exponential growth in power demand and also to size and complexity of the wiring harnesses as well. The substantial range of options available for dealing with emergency aid in dual voltage vehicles is discussed. These options differ in both cost of implementation and relative freedom from failure modes and hazards. The choice will be complex. The decision on which approach to use will likely vary among auto manufacturers. What is critical is not that all manufacturers have exactly the same implementation, but that there is an agreement on the approaches that are taken, and that those varied approaches are compatible once these systems are in the hand of the public. It will be required that all manufacturers use the same connection for the new 36V batteries.
Adaptive neural networks control for camera stabilization with active suspension system

The camera always suffers from image instability on the moving vehicle due to unintentional vibrations caused by road roughness. This article presents an adaptive neural network approach mixed with linear quadratic regulator control for a quarter-car active suspension system to stabilize the image captured area of the camera. An active suspension system provides extra force through the actuator which allows it to suppress vertical vibration of sprung mass. First, to deal with the road disturbance and the system uncertainties, radial basis function neural network is proposed to construct the map between the state error and the compensation component, which can correct the optimal state-feedback control law. The weights matrix of radial basis function neural network is adaptively tuned online. Then, the closed-loop stability and asymptotic convergence performance is guaranteed by Lyapunov analysis. Finally, the simulation results demonstrate that the proposed controller effectively suppresses the vibration of the camera and enhances the stabilization of the entire camera, where different excitations are considered to validate the system performance.
The stability of piles adjacent to a slurry-supported trench

The use of diaphragm walls in many deep excavation projects has become increasingly popular during the past three decades. Diaphragm walls are frequently constructed close to existing structures, and yet the understanding of the interaction between diaphragm wall installation and adjacent structures is very limited. An investigation of the installation effects of diaphragm walls adjacent to piled foundations has been undertaken by means of a series of small-scale model tests in the geotechnical centrifuge at Cambridge University. The research focused on the stability of piles adjacent to a slurry-supported trench in dry dense fine sand. This paper presents a description of the centrifuge model and the observations from a parametric study of the influence of reduction in slurry level on the pile and soil responses. The results suggest that pile stability increases as the length of the trench decreases or when it is at a larger offset distance away from the trench.
Effects of Aluminum as Dopants on the AC Impedance and J-E Behavior of ZnO-Bi203 Ceramics

The effects of the aluminum as dopants on AC impedance and J-E characteristics of ZnO-Biz03 binary ceramics has been investigated. The results from J-E behavior and AC impedance analysis appears that the presence of aluminum in the interface can be responsible for the decrease of the Schottky barrier height and increase grain boundary conductivity. Also, the model based on the resulting dispersion of the grain boundary resistances gives a the impedance plane yields an equivalent circuit modeling consisting of an RC parallel network. This equivalent circuit model rationalizes the effects of dopants on grain and grain boundary. The aim of this study is to investigate the effects of the aluminum as dopants on AC impedance and J-E characteristics of ZnO-Biz03 binary ceramics, and to examine the relation between the microstructure and electrical properties.
Analysis, designing, and experimentation of a transformer-assisted PWM zero-voltage switching pole inverter

This paper proposes a transformer-assisted pulsewidth modulation (PWM) zero-voltage switching pole inverter. As the auxiliary-resonant-commutated pole inverter (ARCPI), the proposal guarantees zero-voltage switching of the main switch and zero-current switching of the auxiliary switch, with a small power auxiliary circuit and full PWM capability. In particular, problems outstanding with the ARCPI such as control complexity, auxiliary switch protection, and center-tap potential variation, etc., are solved in the proposal. The commutation process is discussed step by step in the paper. A detailed analysis for the auxiliary circuit with regard to commutation duration/duty-cycle limitation, auxiliary switch peak current/RMS current, resonant capacitor RMS current, as well as pole output voltage loss are presented afterwards. A design methodology for the auxiliary circuit is recommended based on the analysis. The proposal is experimentally verified with a 4.25 kW half-bridge inverter prototype.
Private and Public: Communication Technologies Between Two Cultural Spaces

(Draft version of paper presented on Cyberspace 2005 Conference, http://cyberspace.muni.cz) The commencement and mainstremization of ICTs strengthened (and from some point of view revived) academic and political discussion on public sphere and public space, as many authors pointed in recent 15 years. The arrival of ICTs also rejuvenated discourses dealing with issues of private space, privacy and intimacy and their relation to technological mediation of everyday social activities. There used to be accented a kind of uniqueness of the cultural impact of ICTs in both ways, and public and private dimensions were often analyzed separately as distinctive areas of enculturation of ICTs, or without a more complex emphasis on historical aspects of these phenomena. This paper aims to put limitations of these approaches in question by employing wider historical and theoretical perspective—this text deals with ICTs in a context of
Performance analysis of chess players comparing traditional and novel cognitive perception ranking measures

Traditionally, proficiency in chess has been measured by metrics based on accuracy and response time or performance in tournaments, but not considering how cognitive signals influence in the decision making in this complex game. In this work, we have carried out a performance analysis of chess players comparing a standard ranking measure with a novel one proposed here. Using the idea of treating participants eye movements and brain signals, when answering several on-screen valid chess questions of distinguished complexities, as high-dimensional data we have shown that expertise is consistently associated with the ability to process visual information holistically using fewer fixations rather than locally focusing on individual pieces. Results show that traditional metric to quantify proficiency presented accuracy up to 73,3%, while the proposed cognitive one reached accuracy up to 87,5% and 98,9% for the electroencephalography and eye movements, respectively. These findings might disclose new insights for teaching and predicting chess skills.
Reasons and motivations for the option of an engineering career in Portugal

Towards the end of their secondary education, students face significant pressures in their decision about their career plan. These pressures are internal and external, personal and social, individual and from the reference group. This paper aims at understanding the reasons driving engineering students’ choices, their perceived needs and aspirations. Moreover, it discusses how, in that process, students are constrained by family and friends and are conditioned by factors such as their socioeconomic and cultural background, employability prospects and gender. The construction of a career map/plan and the reasons and motivations for the option of an engineering career are reviewed, based on the qualitative analysis of students’ discourses. The data indicate the relevance of several criteria such as social status, intelligence, gender, competences, values and interests in the construction of career aspirations. All these levels are highly influenced by self-esteem, which is closely related to the social value of training options and career paths.
Fault Tolerant Control of the Wind Turbine Benchmark using Virtual Sensors/Actuators

Abstract In this paper, the problem of Fault Tolerant Control (FTC) of the wind turbine benchmark is addressed. The paper proposes the use of virtual sensor/actuator approaches to deal with sensor and actuator faults, respectively. The paper suggests the reformulation of these FTC schemes that have been already proposed in state space form in input/output form. The FTC module will use the information from the Fault Detection and Isolation (FDI) module previously designed using set-membership techniques. A fault estimation scheme is also proposed based on batch least squares approach. The performance of the proposed FTC schemes will be assessed using the proposed fault scenarios considered in the FTC benchmark.
Application of Fuzzy Enhancement in the Diagnosis of Liver Cancer from Ultrasound Images

Fuzzy enhancement is applied in computer aided diagnosis of liver cancer from B mode ultrasound images as a pre-processing procedure in this paper. It was evaluated with three classifiers including K means, back propagation neural network and support vector machine using 25 features from single gray-level statistic, gray-level co-occurrence matrix (GLCM), and gray-level run-length matrix (GLRLM). The results show that the fuzzy enhancement algorithm can improve classification accuracy of normal liver, liver cancer and Hemangioma from B mode ultrasound images for three classifiers. It is proved that fuzzy enhancement as an efficient preprocessing procedure could be used in the computer aided diagnosis system of liver cancer.
Vehicle Direct Yaw Moment Control with Longitudinal Forces Distribution

In this paper, a vehicle stability control system is proposed to improve vehicle comfort, handling and stability. The control system includes reference model, DYC controller and Distributer. Reference model is used to obtain the desired yaw rate. DYC controller determines the desired yaw moment by means of sliding-mode technique. Distributer, based on maneuverability and comfort, distributes driving torque or braking torque according to the desired yaw rate. Simulation result shows that the proposed control algorithm can improve vehicle handling and stability effectively.
Interoperability of online loyalty and offline loyalty in omnichannel retailing service: seeking innovation in retail industry

ABSTRACT To stay competitive, retail companies have introduced innovative retailing strategies for enhancing the consumer experience. Among these, omnichannel retailing services are one of the most critical services. However, studies on the loyalty required to secure the market using omnichannel strategies are limited. Instead of arbitrarily selecting key factors for users’ loyalty based on previous research data used by users in social networking services were evaluated in this study, and the validity of the selection of variables was verified through network analysis. A structural equation model based on the results of network analysis and the factors influencing online loyalty and offline loyalty were analysed using the model. Therefore, independent variables except for perceived usability exhibited a positive effect on user satisfaction, and user satisfaction had a positive effect on loyalty. Furthermore, offline user satisfaction exhibited a positive effect on online loyalty, but online user satisfaction did not. Suggestions for future research and corporate strategy were provided.
Volatile Organic Compounds, Indole, and Biogenic Amines Assessment in Two Mediterranean Irciniidae (Porifera, Demospongiae)

Solid phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS) was employed for the headspace determination of the volatile organic fraction emitted by two of the most common Mediterranean demosponges, Ircinia variabilis and Sarcotragus spinosulus, and of indole and some biogenic amines released by sponges in an aqueous medium. A total of 50/30 µm divinylbenzene/carboxen/polydimethylsiloxane and 75 µm carboxen/polydimethylsiloxane fibers were used for the headspace extraction of low molecular weight sulfur compounds from a hermetically sealed vial containing sponge fragments, while the direct immersion determination of indole and biogenic amines was performed. The biogenic amines were extracted after in-solution derivatization with isobutyl chloroformate. All analytical parameters (linearity, limits of detection, and quantification, precision, and recovery) were evaluated for indole and biogenic amines. SPME-GC-MS proved to be a reliable means of highlighting the differences between molecules released by different sponges, principally responsible for their smell. The combined approaches allowed the identification of several volatile compounds in the headspace and other molecules released by the sponges in an aqueous medium, including indole and the BAs cadaverine, histamine, isobutylamine, isopentylamine, propylamine, 2-phenylethylamine, putrescine and tryptamine. The results obtained represent a further contribution to the picture of odoriferous molecules secreted by sponges.
High-efficiency on-board battery charger with transformer isolation, sinusoidal input current and maximum power factor

The paper concerns a battery charger that has been developed for use in a battery powered electric road vehicle. The object is to charge the 144 V traction battery directly from the 220 V supply by drawing sinusoidal current at the input, to obtain, a high efficiency and to have transformer isolation from the supply. To achieve this, the rectified 220 V supply is chopped up to 500 V by a DC to DC convertor and transformed to the necessary voltage for battery charging by using a high-frequency self-oscillating inverter with magnetic feedback. The rectified output of the inverter charges the battery. The step-up chopper controls the transmitted power to the battery and ensures a sinusoidal line current. A detailed description of the power circuit is given and the capabilities of the complete system are proved by extensive measurements.
Batter's behaviour during training when facing a bowling machine and when facing a bowler

In cricket, expert batters must develop anticipatory skills to enable them to respond effectively to a delivery by the bowler. The batter is required to judge the delivery and to move into an appropriate position to respond to it within a limited time (i.e. the delivery transit time can be as little as 450ms for fast-paced bowlers). In training, the batter therefore needs to face numerous deliveries to hone this skill. However, because of the natural variation that occurs in bowling and the high impact experienced by the bowler, bowling machines are often employed to provide numerous similar deliveries for practice and to minimize the occurrence of overuse injuries to the bowler. The purpose of the study presented within this paper was to investigate how the batter reacts differently when facing a bowler and when facing a bowling machine. In a controlled single-subject pilot study a batter faced an unfamiliar bowler and also faced a bowling machine. The batter and the bowler or bowling machine were synchronously filmed using high-speed video cameras operating at 500frames/s and the reaction of the batter was analysed under both conditions. It was seen that the batter lifted his bat backwards significantly earlier (0.999s as opposed to 0.838s before ball release) and lifted his front foot significantly later (0.002s as opposed to 0.153s before ball release) when facing the bowling machine and when facing the bowler respectively.
Nonlinearities in p-i-n microwave photodetectors

The nonlinearities in p-i-n photodetectors have been measured and numerically modeled. Harmonic distortion measurements were made with two single-frequency offset-phased-locked Nd:YAG lasers which provide a source dynamic range greater than 130 dB and a 1 MHz-50 GHz frequency range. Carrier transport is analytically described by three coupled nonlinear differential equations, Poisson's equation and the hole and electron continuity equations. These equations are numerically solved to investigate and isolate the various nonlinear mechanisms. The numerical solution incorporates diffusion since our treatment includes carrier generation in the highly doped p-region of the device. This p-region absorption and carrier-dependent carrier velocities associated with a perturbed electric field (due to space-charge and loading effects) are shown to dominate photodetector nonlinear behavior. The numerical model was extended to predict that maximum photodetector currents of 100 mA should be possible in 20 GHz bandwidth devices before a sharp increase in nonlinear output occurs. In addition, second harmonic distortion improvements of 40-60 dB may be possible if photodetectors can be fabricated with strictly-depleted absorbing regions.
Dual-Band Dual-Polarized Microstrip Antenna for Compass Navigation Satellite System

With the development of China's Compass Navigation Satellite System (CNSS), the demand for terminal antennas is quite urgent. In CNSS system, dual-band antennas are more attractive, because they can provide both the navigation and communication functions. In addition, since the CNSS antennas operate at low frequencies, they are not easy to be installed due to their usually large volumes, limiting their practical application. In this paper, we present a dual-band miniaturized CNSS microstrip antenna based on high-permittivity ceramic substrate. This antenna works at S Band (2492§5MHz, right-handed circular polarization, RHCP) and L Band (1616 § 5MHz, left-handed circular polarization, LHCP). Numerical results show that the impedance bandwidth (S11 < i10dB), 3dB axial ratio bandwidth and antenna gain at L Band are about 26MHz, 6.5MHz and 3.22dB, respectively. While the impedance bandwidth (S11 < i10dB), 3dB axial ratio bandwidth and antenna gain at S Band are about 127MHz, 28MHz and 4.72dB, respectively. An experiment was carried out to verify our design and the measured results agree well with the simulation ones. In addition, by using high-permittivity ceramic ("r = 16) as the substrate, the antenna keeps its performances with a reduced size by 80% comparing with the conventional ones using low-permittivity substrates. This makes it suitable for practical applications.
Challenges, Opportunities, and Threats of Textile Sector in Bangladesh: A Look into the Dacca Dyeing and Manufacturing Company Limited

The textile sector is the most important one in Bangladesh. It is the largest manufacturing sector in the country. The study focuses the present situation of this country's warrants a new vision to accelerate and sustain growth, alleviate poverty, take advantage of new opportunities, threats and meet challenges of the future and how to play its rightful role in a competitive global market. The study was based on primary and secondary data followed by the statistical test like mean value, standard deviation, coefficient of variance, t-test etc. The textile sector, whose contributions to industrial GDP and employment are the highest in Bangladesh. DDMCL (Dacca Dyeing and Manufacturing Company Limited) has excellent production, sales and financial performance due to favourable local and foreign sales and satisfactory earning profit. The bright future of the garment sector has created a good demand for our yarn and fabrics and taps this opportunity; we need congenial business environment and backward linkage industries for the survival of our textile sector. In spite of that, in this study attempts has been made to find out some problems and identifying the challenges, opportunities and threats of DDMCL for the global market. This might be a good lesson for other Textile Industries of Bangladesh.