Miracle-dz/UniFAR-FTUs huggingface dataset:
Microwave amplitude equalizer

This short paper presents the model of a broadband amplitude equalizer operating within the 6-18 GHz band. The equalizer attenuation decreases with increasing frequency, i.e., the equalizer characteristic behaves in opposition to any microwave passive components, e.g., cables, transmission lines, etc. Due to this, connecting the equalizer into a microwave system results in equalizing the frequency characteristics.
Receiver and optics designs for the 100-meter Green Bank telescope

A 100-m-diameter, fully steerable, offset dual reflector radio telescope is under construction at the Green Bank, West Virginia, facility of the National Radio Astronomy Observatory (NRAO). Significant performance improvement is expected of the offset design over that possible with symmetrical antennas. The antenna will be capable of operation from below 300 MHz to above 40 GHz. To take full advantage of the offset design, ultra-low-noise cryogenic receivers will be constructed and installed. The trade-offs made in the design of the microwave optics are summarized, and plans for receivers and associated equipment are described. <<ETX>>
Some tests of flat plate photovoltaic module cell temperatures in simulated field conditions

The nominal operating cell temperature (NOCT) of solar photovoltaic (PV) modules is an important characteristic. Typically, the power output of a PV module decreases 0.5% per deg C rise in cell temperature. Several tests were run with artificial sun and wind to study the parametric dependencies of cell temperature on wind speed and direction and ambient temperature. It was found that the cell temperature is extremely sensitive to wind speed, moderately so to wind direction and rather insensitive to ambient temperature. Several suggestions are made to obtain data more typical of field conditions.
Electrical Properties of Graphite Nanoparticles in Silicone: Flexible Oscillators and Electromechanical Sensing

This thesis reports the discovery of a wide negative di↵erential resistance (NDR) region in a graphite-silicone composite that was utilized to create a strain-tuned flexible oscillator. Encoding the strain into frequency mimics the behavior of mechanoreceptor neurons in the skin and demonstrates a flexible and electronically active material suitable for state of the art bio-electronic applications. The NDR was investigated over a range of composite filling fractions and temperatures; alongside theoretical modelling to calculate the tunneling current through a graphite-silicone barrier. This led to the understanding that the NDR is the result of a semi-metal to insulator transition of embedded graphene bilayers within the graphite nanoparticles. The transition, brought about by a transverse bias across specifically orientated particles, opens a partial band-gap at the Fermi level of the bilayer. NDR in a flexible material has not been observed before and has potential for creating a flexible active device. The electromechanical properties of the composite were considered through a bend induced bilayer strain. The piezoresistance was found to be dominated by transient resistance spiking from the breaking of conduction lines, which then reform according to the viscoelasticity of the polymer matrix. The resistance spiking was embraced as a novel method for sensitive di↵erential pressure detection, used in the development of two applications. Firstly, it was employed for the detection of ultrasound waves and found to have an acoustic pressure detection threshold as low as 48 Pa. A commensurability was observed between the composite width and ultrasound wavelength which was shown to be consistent with the formation of standing waves, described by Bragg’s law. Secondly, a differential pressure array of 64 composite pixels was fabricated and demonstrated to image pressures under 3.8 kPa at a resolution of 10 dpi. The NDR active region was incorporated into an LC circuit where it was demonstrated to sustain oscillations of up to 12.5 kHz. The composite was then strained and an intrinsic frequency was observed which had a linear dependence on the strain with a frequency shift of 84 Hz / % strain. Lastly the composite was used in a strain-tuned amplifier circuit and shown to provide a gain of up to 4.5. This thesis provided the groundwork for a completely flexible electronically active device for futuristic bio-electronic skins with resolutions and sensitivities rivalling those of human tactile sensing.
Regional Energy Deployment System (ReEDS)

The Regional Energy Deployment System (ReEDS) is a deterministic optimization model of the deployment of electric power generation technologies and transmission infrastructure throughout the contiguous United States into the future. The model, developed by the National Renewable Energy Laboratory's Strategic Energy Analysis Center, is designed to analyze the critical energy issues in the electric sector, especially with respect to potential energy policies, such as clean energy and renewable energy standards or carbon restrictions. ReEDS provides a detailed treatment of electricity-generating and electrical storage technologies and specifically addresses a variety of issues related to renewable energy technologies, including accessibility and cost of transmission, regional quality of renewable resources, seasonal and diurnal generation profiles, variability of wind and solar power, and the influence of variability on the reliability of the electrical grid. ReEDS addresses these issues through a highly discretized regional structure, explicit statistical treatment of the variability in wind and solar output over time, and consideration of ancillary services' requirements and costs.
Study of an Integration Platform Based on an Adiabatic Active-Layer Waveguide Connection for InP Photonic Device Integration Mirroring That of Heterogeneous Integration on Silicon

In this work, a photonic device integration platform capable of integration of active-passive InP-based photonic devices without the use of material regrowth is introduced. The platform makes use of an adiabatic active-layer waveguide connection (ALWC) to move an optical beam between active and passive devices. The performance of this platform is analyzed using an example made up of four main sections: (1) a fiber coupling section for enabling vertical beam coupling from optical fiber into the photonic chip using a mode-matched surface grating with apodized duty cycles; (2) a transparent waveguide section for realizing passive photonic devices; (3) an adiabatic mode connection structure for moving the optical beam between passive and active device sections; and (4) an active device section for realizing active photonic devices. It is shown that the coupled surface grating, when added with a bottom gold reflector, can achieve a high chip-to-fiber coupling efficiency (CE) of 88.3% at 1550 nm. The adiabatic active-layer mode connection structure has an optical loss of lower than 1% (CE > 99%). The active device section can achieve an optical gain of 20 dB/mm with the use of only 3 quantum wells. The optimized structural parameters of the entire waveguide module are analyzed and discussed.
Decentralized output feedback fault-tolerant control for uncertain large-scale systems

In this paper, three decentralized output feedback fault-tolerant control methods of design integrity with actor failures, sensor failures and mixed failures are presented for uncertain interconnected large-scale systems. Not only can they make the faulty closed large-scale systems asymptotically stable under the uncertain bounded parameters, but also assure the H/sup /spl infin// properties are optimal or suboptimal. The example simulations demonstrate that the methods are effective. <<ETX>>
A Building-Block Favoring Method for the Topology Optimization of Internal Antenna Design

This paper proposes a new design technique for internal antenna development. The proposed method is based on the framework of topology optimization incorporated with three effective mechanisms favoring the building blocks of associated optimization problems. Conventionally, the topology optimization of antenna structures discretizes a design space into uniform and rectangular pixels. However, the defining length of the resultant building blocks is so large that the problem difficulty arises; furthermore, the order of the building blocks becomes extremely high, so genetic algorithms (GAs) and binary particle swarm optimization (BPSO) are not more efficient than the random search algorithm. In order to form tight linkage groups of building blocks, this paper proposes a novel approach to handle the design details. In particular, a nonuniform discretization is adopted to discretize the design space, and the initialization of GAs is assigned as orthogonal arrays (OAs) instead of a randomized population; moreover, the control map of GAs is constructed by ensuring the schema growth based on the generalized schema theorem. By using the proposed method, two internal antennas are thus successfully developed. The simulated and measured results show that the proposed technique significantly outperforms the conventional topology optimization.
Artificial Neural Networks for Civil Engineers: Fundamentals and Applications

From the Publisher: This monograph provides researchers with an understanding of the potential of artificial neural networks for solving civil engineering related problems, and guidance on how to develop successful implementations for a broad range of problems. Fundamental issues in the selection, development, and use of neural networks, as well as example applications to each of the various disciplines in civil engineering are presented. An introduction to neural networks is provided, along with a classification of the various forms of neural networking systems available (architectures, modes of operation, and methods of development).
Design and performance of a gas-turbine engine from an automobile turbocharger /

The Massachusetts Institute of Technology Department of Mechanical Engineering teaches thermodynamics and fluid mechanics through a pair of classes, Thermal Fluids Engineering I & II. The purpose of this project was to design and fabricate a gas-turbine engine for demonstration use in these two classes. The engine was built from an automobile turbocharger with a combustion chamber connected between its compressor and turbine. Pressure and temperature sensors at different points of the engine cycle allow students to monitor the performance of the individual engine components and the complete engine cycle. Thesis Supervisor: Ernest Cravalho Title: Professor of Mechanical Engineering
F/A-18(A-D) wing root Fatigue Life Expended (FLE) prediction without the use of strain gage data

Abstract : U.S. Navy and Marine Corps F/A-18 aircraft are subject to two life-limiting metrics--actual flight hours and fatigue life expended (FLE). While flight hours can be mitigated, fatigue on the airframe cannot. The fatigue expended per flight varies based on the mission; it is recorded by seven strain gages throughout the airframe. Because strain gages are unmonitored systems, they are subject to drift and/or failure. Consequently, Naval Air Systems Command (NAVAIR) accumulates approximately a month of strain gage data for each Navy and Marine Corps F/A-18 before analyzing the data for such anomalies. This results in a latency period of roughly six weeks between the mission being flown and the squadron receiving the FLE for that mission. This research identifies regression models by which to predict the NAVAIR reported FLE using real-time metrics stored by the aircraft during flight, thereby, eliminating the latency issue and allowing squadrons to better manage their aircraft. This research shows that the NAVAIR FLE number can be accurately predicted (adjusted R squared approx. 0.95) using in-flight metrics, such as weight-off-wheels time, minimum g, maximum g, and wing root trigger events.
Examining the Effects of Learning Organization Discipline on Employee Readiness and Organizational Commitment

Learning Organization is an organization whose members continuously improve or expand their abilities to create the results they really want where new and expansive thinking patterns are cultivated, aspirations are developed, and its members continuously learn how to learn together. Learning organization is important aspect to enhance the development of the learning process in higher education, especially in the education 4.0 era. The aim of this empirical study was to examine the effect of learning organizational discipline on employee readiness and organizational commitment. To achieve this objective the data was collected using an online survey from 96 academic staff at Public University in Indonesia. The collecting data technique used questionnaires with a 5-point Likert scale ranging from 1 (strongly disagree) to 5 (strongly agree). a 5-point Likert scale ranging from 1 (strongly disagree) to 5 (strongly agree). This research was using quantitative method, PLS, and SPSS. The finding indicate that 3 hypotheses have significant positive effect. Learning organization discipline has significant positive effect on employee readiness, learning organization discipline has significant positive effect on organizational commitment, and employee readiness has significant positive effect in organizational commitment. University needs to develop organizational commitment and employee readiness by adopting learning organization discipline. Keywords—organizational commitment, readiness, learning organization, staff academic, university
Metal Additive Distribution in TiO2 and SnO2 Semiconductor Gas Sensor Nanostructured Materials

Recently, there has been an increasing interest in the electronics world for those aspects related to semiconducting gas sensor (SGS) materials. In view of the increasingly strict legal limits for pollutant gas emissions, there is a great interest in developing high performance gas sensors for applications such as controlling air pollution and exhaust gases. In this way, semiconductor gas sensors offer good advantages with respect to other gas sensor devices (such as spectroscopic and optic systems), due to their simple implementation, low cost and good reliability for real-time control systems. In the present work, we have been especially interested in the study of the different ways of metal additive distribution in the most common SGS materials used nowadays and furthermore in the physical and chemical sensing properties they can achieve.
Thermal characterization of a thermally enhanced QFN package

This paper addresses the development of thermally enhanced (advanced) Quad Flat No lead or QFN package. The QFN package is a promising choice for portable wireless applications such as Bluetooth and Home RF. This package offers attractive attributes in terms of a near CSP footprint, good electrical and thermal characteristics. Thermal characterization of a new thermally enhanced QFN type of package named as HQFN. The HQFN package structure is similar to a normal QFN package except that it has an exposed heat spreader attached to the active die using a die-attach film (DA film) material. The study is done in comparison with a normal QFN type of package using commercial CFD simulation software and validated with experiments. Sensitivity analysis is made for the effect of DA film material thermal conductivity and effect of heat spreader size. The new HQFN package is able to achieve a better thermal performance than normal QFN without thermally saturating the PCB. Simulation results show that with a metal housing attached to the top of the package, it is possible to achieve thermal improvement of more than 20% under airflow conditions, and around 10% improvement under still-air conditions, when compared to a normal QFN package under the same test conditions.
Bio-Structural Analogues in Architecture

This book seeks to discover the architectural potential of biological structures as they can be found in nature. The structures that give biological forms strength, movement, firmness, and flexibility are studied, illustrated, and used as an inspiration for a huge number of design experiments of which the thinking, working, and final prototyping process are shown.
A comparison of knee muscle activation and knee joint stiffness between female dancers and basketball players during drop jumps

"This dissertation compared knee muscle activation of the lateral gastrocnemius, medial and lateral hamstrings, and lateral quadriceps (LG, MH, LH, and LQ) and knee joint stiffness(KJS) between female dancers(D) and basketball players(B) during the initial landing of a double-leg drop jump. The purpose was to examine possible neuromechanical strategies dancers employ that might protect them from Anterior Cruciate Ligament (ACL) injuries during a potentially high ACL-injury risk activity. Fifty-five females (D=35, 20.7+2.3yrs, 164.3+6.7cm,62.2+1.9kg, B=20,20.1+2.0yrs, 170.5+6.1cm,72.6+11.4kg) performed 5 double-leg drop jumps from a 45cm box. Muscle activity was recorded via surface electromyography (sEMG). A force plate and three-dimensional electromagnetic tracking system were used to record kinetic and kinematic data and calculate KJS (ratio of change in sagittal knee moment to sagittal knee flexion angle from ground contact to maximum knee flexion). sEMG data were normalized to maximum volitional isometric contractions(%MVIC), and joint moments to body weight (Nm/kg). Separate 2x4 ANOVAs compared D and B on muscle onsets (ms) and mean RMS amplitudes (%MVIC) before (PRE=150 ms) and after (POST=50 ms) ground contact. A one-way ANOVA examined group differences in KJS (Nm/kg°), with a stepwise regression model examining prediction of KJS. No significant group differences were observed in muscle onsets (D=133.4+53.2ms, B=121.6+50.2ms;P=.22), activation amplitudes (PRE: D=28.1+8.7%MVIC, B=27.7+10.5%MVIC;P=.60; POST: D=51+17.3%MVIC, B=49.6+21.4%MVIC;P=.78), or KJS (D=.0163+.009Nm/kg°, B=.0185+.011Nm/kg°;P=.44). Due to recruitment challenges the proposed full complement of participants (N=70;D=35,B=35) was not achieved. Moderate effect sizes (ES) between-groups indicated a trend towards higher muscle activation levels in dancers in MH both pre (34vs.26%MVIC;ES=.55) and post (38vs.25%MVIC;ES=.41) contact, and in LG post contact (45vs.35%MVIC;ES=.33). The exception was LQPOST (90vs.109%MVIC;ES=.30) where dancers had a tendency for lower muscle activation levels. Prelanding muscle activation amplitudes and group membership were not able to predict changes in KJS. These results suggest that the lack of findings may in-part be due to low statistical power. Further, although KJS did not differ between groups, between-group effect sizes noted in LGPOST, MHPRE, POST, and LQPOST suggest possible differences in neuromechanical strategies over other lower extremity joints. Additional research is necessary to determine possible ACL-injury protective mechanisms employed by dancers during other high ACL-injury risk activities. "--Abstract from author supplied metadata.
Sensorless speed control of a PM synchronous motor by sliding mode observer

This paper presents a sensorless speed control of a permanent magnet synchronous motor using a sliding mode observer. A vector control strategy is considered, for a motor with sinusoidal flux distribution. The sliding mode observer detects the voltages induced by the magnet flux on the stator windings. These signals are used to calculate the rotor position and speed needed for vector control. Due to the sliding mode operation, filters are used to smooth the estimated variables. A speed-dependent compensation is also proposed, in order to achieve an accurate estimation of the rotor position. As the observed variables are not available below a limit frequency, an open loop starting procedure is implemented. The resulting observer has been fully analyzed by simulations, in order to test the performance both in steady-state and transient operations. Experimental results based on a DSP TMS320C50 controller are presented, showing the performance of the sensorless drive over a wide range of operating conditions.
Efficient Choice of a Multilevel Inverter for Integration on a Hybrid Wind-Solar Power Station

DC/AC converters are very important components that have to be chosen efficiently for each type of power station. In this article, we present in details, a comparison between three different architectures of multilevel inverters, the flying capacitor multilevel inverter (FCMLI), the diode clamped multilevel inverter (DCMLI), and the cascaded H-bridge multilevel inverter (CHMLI). Thus the comparison is focused on the output voltage quality, the complexity of the power circuits, the cost of implementation, and the influence on a power bank inside the renewable power station. We also investigate trough simulation the efficient number of levels and suitable characteristics for the CHMLI that showed the most promising performance. The study uses Matlab Simulink platform as a tool of simulation, and aim to choose the most qualified inverter, for a potential insertion on a hybrid renewable energy platform (wind-solar). In all the simulations we use the same PWM control type (SPWM).
Robust Trapped-Ion Quantum Logic Gates by Microwave Dynamical Decoupling

We introduce a hybrid scheme that combines laser-driven phonon-mediated quantum logic gates in trapped ions with the benefits of microwave dynamical decoupling. We demonstrate theoretically that a strong driving of the qubit decouples it from the external magnetic noise, and thus enhances the fidelity of two-qubit quantum gates. Moreover, the scheme does not require ground-state cooling, is inherently robust to undesired ac-Stark shifts, and simplifies previous gate schemes thus decreasing the effort in their realization.
Tracking with Time-Delayed Data in Multisensor Systems

Abstract : When techniques for target tracking are expanded to make use of multiple sensors in a multiplatform system, the possibility of time delayed data becomes a reality. When a discrete-time Kalman filter is applied and some of the data entering the filter are delayed, proper processing of these late data is a necessity for obtaining an optimal estimate of a target's state. If this problem is not given special care, the quality of the state estimates can be degraded relative to that quality provided by a single sensor. A negative-time update technique is developed using the criteria of minimum mean-square error (MMSE) under the constraint that only the results of the most recent update are saved. The performance of the MMSE technique is compared to that of the ad hoc approach employed in the Cooperative Engagement Capabilities (CEC) system for processing data from multiple platforms. It was discovered that the MMSE technique is a stable solution to the negative-time update problem, while the CEC technique was found to be less than desirable when used with filters designed for tracking highly maneuvering targets at relatively low data rates. The MMSE negative-time update technique was found to be a superior alternative to the existing CEC negative-time update technique. Multisensor systems, Kalman filter, Cooperative Engagement Capabilities (CEC) technique, Minimum Mean-square Error (MMSE) technique.
Excellence profiles in Spanish firms with quality management systems

This paper seeks to answer two important questions that firms consider when designing, implementing and improving a quality management system (QMS): (1) what are the critical or key factors in implementing, developing and improving a QMS; and (2) what results can we expect from these factors? This article's primary new contribution to these questions is to propose the construction of an indicator that we call the reformed excellence predictor (REP). This indicator is obtained by taking as reference a sample of over 100 Spanish firms with experience in processes of implementation, development and improvement of quality. Once we have constructed the indicator, using multivariate statistical and graphic techniques, we analyse the implementation profiles and the results of the firms that have achieved the highest levels of excellence for the indicator designed.