Miracle-dz/UniFAR-FTUs huggingface dataset:
ANALYSIS AND DESIGN OF A PARALLEL RESONANT CONVERTER INCLUDING THE

A high frequency link dc/dc parallel resonant converter operating above resonance is analysed including the effect of high-frequency transformer using state-space approadi. Steady-state solutions are derived and are used to obtain the design curves. A method of obtaining optimum operating point under certain constraints is developed and is used to present a simple design procedure. The analysis shows that the inclusion of a high frequency transformer results in the introduction of a new mode of operation in between the two general steady-state modes. Experimental results obtained with a MOSFET based PRC for three different transformer turns ratios are presented to support the theory.
Prediction of Concrete Strength Using Neural-Expert System

Over the years, many methods have been developed to predict the concrete strength. In recent years, artificial neural networks (ANNs) have been applied to many civil engineering problems with some degree of success. In the present paper, ANN is used as an attempt to obtain more accurate concrete strength prediction based on parameters like concrete mix design, size and shape of specimen, curing technique and period, environmental conditions, etc. A total of 864 concrete specimens were cast for compressive strength measurement and verification through the ANN model. The back propagation-learning algorithm is employed to train the network for extracting knowledge from training examples. The predicted strengths found by employing ANN are compared with the actual values. The results indicate that ANN is a useful technique for predicting the concrete strength. Further, an effort to build an expert system for the problem is described in this paper. To overcome the bottleneck of intricate knowledge acquisition, an expert system is used as a mechanism to transfer engineering experience into usable knowledge through rule-based knowledge representation techniques.
Analysis of Flux Distribution and Core Losses in Interior Permanent Magnet Motor

Abslract - The interior permanent magnet (1PM) motor with its robust rotor construction, hybrid torque productioll nalure and fluxweakening capability is suitable for electric veliicle applications wherc wide speed and torque range is required. At high-speed operations, core losses become an important issiic because they affect efficiency and raise operating temperatures. This paper discusses the results of two-dimensional tinite elcinent analysis into the relationship between flux distribution and core losses iii the IPM motor. The analysis is further supported by flux ineasureinents using search coils installed in an experimental iiiotor. Three iiielhods of predicting the core losses in IPM motor are also iiivestigated. Tliesc methods are the empirical formula melhod, finite element computed waveform method and the search coil induccd voitilgc method. the rotor can withstand much higher centrifugal force when compared to surface-mounted permanent magnet motors. This is very ilnportant in EV applications, where the motors are required to run at high speeds for long durations, In the design of motors, ensuring that the maximum temperature ofthe winding insu'ation is not exceeded is very Of rare-earth magnets wed in PM motors, it is ais0 important to limit the maximum magnet temperature to avoid loss of remanent flux density and peak torque capability. Prediction of motor temperature requires techniques of estimating the various types of power losses in the motor. The copper losses of the stator windings and the In the
Reliability analysis of the 4.5 roller bearing

Abstract : The J-52 engine used in the EA-6B Prowler has been found to have a faulty design which has led to in-flight engine failures due to the degradation of the 4.5 roller bearing. Because of cost constraints, the Navy developed a policy of maintaining rather than replacing the faulty engine with a re-designed engine. With an increase in Prowler crashes related to the failure of this bearing, the Navy has begun to re-evaluate this policy. This thesis analyzed the problem using methods in reliability statistics to develop policy recommendations for the Navy. One method analyzed the individual times to failure of the bearings and fit the data to a known distribution. Using this distribution, we estimated lower confidence bounds for the time which 0.0001% of the bearings are expected to fail, finding it was below fifty hours. Such calculations can be used to form maintenance and replacement policies. Another approach analyzed oil samples taken from the J-52 engine. The oil samples contain particles of different metals that compose the 4.5 roller bearing. Linear regression, classification and regression trees, and discriminant analysis were used to determine that molybdenum and vanadium levels are good indicators of when a bearing is near failure.
Effect of Storage Method and Storage Duration on Chicken Egg Quality

— Poultry production is a fast growing industry and has become a dependable source of obtaining income for many farmers. There is therefore a growing need for technologies to preserve poultry products, in this case eggs, to prevent or reduce post-harvest losses. The aim of this present study is to evaluate the effect of storage method and duration on internal and external egg quality traits of eggs stored under three different storage conditions. A total of 190 eggs (from Isa brown breed hens aged 51 weeks) were used for the analysis. The storage methods to which the eggs were subjected included; 1) Cold Storage (M1), 2) Saw dust (M2) and 3) Control (M3) at a temperature range of 26°C- 32°C.The eggs were stored for 15 days, while the readings were taken at three day intervals. Albumen height, haugh unit, yolk index and egg weight have been found to be important parameters influenced by storage method and storage duration. Cold storage had the highest value for albumen height, haugh unit, yolk index and egg weight, while eggs stored under sawdust had no significant difference from those under control. Duration however had a deteriorating effect on important egg quality traits form D3 to D15 as could be observed in Albumen weight (41.14 to 36.37), Haugh unit (73.0 to 55.1), Yolk Index (36.99 to 26.61) and Egg weight (61.85 to 56.76). Thus, lower egg quality was recorded as storage time increased. Results from the first microbial analysis (freshly laid eggs) showed that no organism was isolated. Coliform bacteria, mold and yeast were isolated from eggs stored using cold storage and control conditions respectively. This study showed that eggs stored under cold storage retained both internal and external quality traits for longer time than those stored under sawdust and control, after the eggs had been stored for 15 days.
Challenges and Expectations of Online Arabic Language Teaching In The Covid-19 Pandemic Era

The Covid-19 pandemic has changed the educational landscape around the world. In this era, higher education institutes offer fully online teaching and learning delivery as an alternative implementation. During the transition period, faculty and students experimented extensively to adapt to the new norms of education. This paper aims to reveal the positive academic experiences of Arabic language teachers during the past semester and their challenges. Belief in one's ability and readiness to face the coming day is essential for the following action plan by those in charge. It becomes an indicator for individuals to equip themselves and not be adequate with existing skills. Data were obtained through a questionnaire instrument to 12 respondents of Arabic language instructors and then analyzed based on the Fuzzy Delphi method. The study lists five (5) positive experiences and three (3) most fundamental challenges of online teaching. Belief in the readiness of implementing online teaching for the coming semester was also expressed. The actual situation of the teaching staff is an essential indicator in evaluating the effectiveness and quality of delivery during the Covid-19 pandemic. The educational landscape is far from changing and will never return to how it was before.
The Application of Thermoelectric Spot Cooling to Electronic Equipment

Summary Recent developments in the construction of thermoelectric coolers have resulted in improved coolers suitable for use in electronic equipment. The continual effort to improve the techniques of cooling electronic equipment led to the investigation of thermoelectric spot cooling of temperature-limiting component parts located within local areas of an electronic equipment. The investigation consisted of the evaluation and application of nine spot coolers constructed to specifications determined by an analysis. Thermal evaluation of the nine spot coolers showed that each spot cooler either met or exceeded the design requirement of pumping 5 w over a 30°C temperature difference. The coefficient of performance exceeded 0.5 for each of the spot coolers operated under the design condition. In addition to the satisfactory thermal performance, a spot cooler passed the mechanical shock and vibration requirements for satellite equipments used in Project Mercury. The information on spot cooler thermal performance was employed in an analytical application of spot cooling to a free-convection and radiation-cooled equipment and a forced-convection-cooled equipment. The results indicate that free-convection - and radiationcooled equipment can be operated in higher temperature environments with spot cooling; moreover, the cooling requirements for forced-convection-cooled equipment can be reduced.
Estimation of train dwell time at short stops based on track occupation event data A study at a Dutch railway station

Train dwell time is one of the most unpredictable components of railway operations, mainly due to the varying volumes of alighting and boarding passengers. However, for reliable estimations of train running times and route conflicts on main lines, it is necessary to obtain accurate estimations of dwell times at the intermediate stops on the main line, the so-called short stops. This is a great challenge for a more reliable, efficient and robust train operation. Previous research has shown that the dwell time is highly dependent on the number of boarding and alighting passengers. However, these numbers are usually not available in real time. This paper discusses the possibility of a dwell time estimation model at short stops without passenger demand information by means of a statistical analysis of track occupation data from the Netherlands. The analysis showed that the dwell times are best estimated for peak and off-peak hours separately. The peak-hour dwell times are estimated using a linear regression model of train length, dwell times at previous stops and dwell times of the preceding trains. The off-peak-hour dwell times are estimated using a non-parametric regression model, in particular, the k -nearest neighbor model. There are two major advantages of the proposed estimation models. First, the models do not need passenger flow data, which is usually impossible to obtain in real time in practice. Second, detailed parameters of rolling stock configuration and platform layout are not required, which makes the model more generic and eases implementation. A case study at Dutch railway stations shows that the estimation accuracy is 85.8% - 88.5% during peak hours and 80.1% during off-peak dwell times at short stop stations without passenger data is possible.
Network Centric Multiple Manned/Unmanned Systems (UMS) Navigation and Control Coordination

Armed unmanned systems (UMS) are beginning to be fielded in the current battlespace, and extremely common in the Future Force Battlespace. One of the major concerns of UMS development is the evolution from human intervention to Robot autonomy/intelligence. The system autonomy has been evaluated by a spectrum of measures from obstacle detection/avoidance, route planning to mission planning, pattern recognition and situation awareness. Many system level issues pertaining to collaborative behavior and swarm intelligence need to be investigated. Recently the US Army Armaments Research, Development and Engineering Center (ARDEC), developed the concept of a joint manned-unmanned system team (JMUST), for which target handoff and sharing of situational awareness (SA) data between humans and UMS working together have been demonstrated. This is a ground- breaking program in terms of implementation of advanced concepts for human-UMS teaming in combat operations, which currently has no parallel in either the Future Combat System (FCS) or Future Force Warrior (FFW) programs. With the ARDEC Combat Decision Aids System (CDAS) software system and digital UHF radios providing the network backbone, both UMS and human acquired target and SA data have been shared to all squad level assets. As a demonstration UMS platform for network centricity this paper presents personnel/platform tracking, navigation and communication system as an essential part for FCS, FFW, Objective Force Warrior, Land Warrior and Homeland Defense applications where one urgently needs to have novel position/location tracking, communications system and decision making devices that would permit multi-tracking, reporting and recording operations. This Intelligent Precision Geolocation and Control Networked Multiple UMS Demonstration system provides precision interruption-free position for multiple tracking of UMS and other combat platforms, in complicated environments and terrains. The system integrated with CDAS is realized by using the coremicro Palm Navigators with wireless ad hoc networks to perform communications and wireless location at the same time, with improved geolocation accuracy, and increased tracking area coverage. A suite of information multi-sensor fusion and wireless communications was demonstrated. The system demonstration of the fully-functional toolsets for robotics, robotic autonomy, robotic human interface, remote targeting and surveillance is presented in fusion algorithms based on the integration configuration of this paper. In recent testing the non-magnetic CPN walker unit, with the coremicro 4D GIS and CDAS with the indoor floor map of a large building was accurate as expected for indoor tracking. The maximum tracking loop in the building had a 1 to 2 meters position error.
Combined Piezoelectric-Hydraulic Actuator Based Active Vibration Control for Rotordynamic System

Previous research by the authors concentrated on using piezoelectric actuators for active vibration control (AVC) of rotating machinery. The current work extends this by positioning the piezo-actuator remotely from the controlled structure and transmitting the control force via a hydraulic line and two pistons. Liquid plastic (LP) is employed as a transmission “fluid” to obtain a high bulk modulus and low leakage. The paper presents results for bulk moduli measurement, and bench and rig tests for the entire actuator system. These results show the high effectiveness of the hybrid actuator for controlling vibrations on a laboratory rotor test rig.
Design and implementation of a high‐performance 60‐GHz CMOS slot antenna

This article describes the design and implementation of a monolithic 60‐GHz millimeter‐wave planar CMOS slot antenna. A finite element method‐based three‐dimensional full‐wave electromagnetic solver, high‐frequency structure simulator, is used to simulate and optimize the performance of the antenna. The feeding network adopts the coplanar waveguide (CPW) structure, so the on‐chip antenna can be flip‐chip bonded to a CPW RO4003 conversion board for complete radiation‐pattern measurement. Nearly, omnidirectional operation is achieved by providing four major current paths in the shape of a cross for radiation. The measured input voltage standing wave ratio of the on‐chip slot antenna is smaller than 2 for frequencies 54.6–68.3 GHz. The measured maximum power gain is −0.74 dB at 60 GHz, one of the highest power gains ever reported for a CMOS antenna at 60 GHz. The chip area is only 1 × 0.8 mm2, i.e., 0.8 mm2. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2061–2065, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27012
Overview of current technology in MMW radiometric sensors for law enforcement applications

This paper discusses the current state-of-the-art in millimeter-wave radiometric imagers being developed for law enforcement use within the United States. The most prevalent application at present is the detection of concealed weapons (guns, knives, etc.) with a secondary application involving the detection of drugs and explosives. Three main topics will be addressed: the phenomenology of concealed weapon detection at millimeter wavelengths, the promise and short comings of first generation radiometric imagers, and the characteristics of second generation systems currently under development.
Assessment of Human Factor Performance Using Bayesian Inference and Inherent Safety

Simply attributing incidents to human error is not adequate; human factors aspects should be investigated such that lessons are learnt and the true root causes are established in order to prevent recurrence. Whilst many petroleum and allied industry businesses have investigated and analyzed incidents – whether with major hazards or occupational injuries potential – human factors aspects are rarely addressed sufficiently. Therefore, this paper presents a hybrid methodology that combines a conventional Swiss Cheese model with Bayesian inference to predict the failure probability of human factors. An inherent safety concept associated with human factor is proposed and utilized as preventive measures to overcome the identified root causes. This approach is then applied to offshore safety assessment study. As a result, the failure probability of human factor can be monitored with time and the best preventive measure can be prioritized once human performance is degraded. It is proven that the approach has the ability to act as predictive tool that provides early warnings toward human deficiency. A preventive measure can then be taken to enhance the overall human performance and ultimately to reduce the likelihood of major incidents.
Appendix: Reply to the letter to the editor

Thompson et al. have offered some opinions regarding the use of numerical data and quantitative risk analysis (QRA) for security assessments. I will address the issues they have raised and provide technical justifications for my views. These are important issues for security risk analysis and need to be addressed in some detail. However, it should be noted that the topic of my paper was Rings of Protection Analysis (ROPA), the security equivalent of Layers of Protection Analysis (LOPA) used in safety analysis, and that ROPA is not QRA any more than LOPA is QRA. The American Institute of Chemical Engineers (AIChE) views LOPA as “a method that falls between qualitative and quantitative methods” [1]. The same is true for ROPA.
Evaluating the perceived visual complexity of multidirectional hill-shading

: Eye tracking recordings could reveal the visual behavior for different carto-graphic visualization techniques, such as hill-shading, while at the same time eye tracking metrics (ETMs) can summarize the associated complexity levels in a concise and quantitative manner. In the present study, three different hill-shading methods, including: (i) the standard method based on ideal diffuse reﬂection, (ii) the Multidirectional Oblique-Weighted method – MDOW and (iii) the combination of a MDOW’s variation with standard hill-shading, are evaluated and ranked in terms of their perceived visual complexity. The performed examination is based on both eye tracking techniques and expert judgement procedures. A weighted combination of basic ETMs has been used, implemented by the Landscape Rating Index – LRI. The weights resulted from an experts’ judgement process where the opinions of experts in geoinformatics, cartography, geovisualization, experimental psychology, cognitive science, neuroscience and eye tracking were analyzed. Fifteen (15) individuals participated in an eye tracking experiment with hill-shading images produced by the three methods under evaluation, while 41 experts participated in an online questionnaire in order to collect all the analysis data. The ﬁnal evaluation was based on the computation of three LRI models. The outcomes indicate that implementing hill-shading with more than one light sources results in similar perceptual behaviors, allowing for a seamless exploitation of the advantages of using multidirectional illumination.
Redefining Online Social Network and Its Influence on Word of Mouth Marketing

Word-of-mouth marketing (WOMM) has currently garnered a great deal of attention in marketing strategy, especially over online channels. Numerous studies had attempted to identify its effectiveness by conducting experiments on several online community sites, such as Blogger and Foursquare. However, its effectiveness and user motivations in order to adopt WOMM that constitute the essential components of such strategy are still unclear. In addition, only a few of these studies performs the research on pure online social platform, which theoretically divided into 2 major types: online social community and online social network. Therefore, this study is attempting to fill the theoretical gap by focusing on online social network. To tackle this problem, we collect data from an online experiment using Facebook website. In particular, we are interested in examining the impact of WOMM toward online social network and their effectiveness. Our result shows that there is no correlation between interactions of potential WOMM adopters and WOMM adopters and WOMM adoption behavior through the network. On the other hand, tie strength among users lead to WOMM adoption behavior of the potential WOMM adopters. The finding suggests a new way to utilize online social platform as a channel toward WOMM.
International harmonized research activities report of working group on intelligent transport systems (ITS)

The International Harmonized Research Activities Working Group on Intelligent Transport Systems was established to coordinate government research aimed at developing harmonized procedures for the evaluation of safety of in-vehicle information, control and communication systems with respect to human performance and behaviour. It deals with human-machine interactions in the broadest sense of that phrase. However, it is acknowledged that even in its broadest sense, human-machine interactions is only a part of ITS safety. This report describes the activities completed in the past five years, including the formulation of an overall framework for ITS safety assurance indicating the role of the ITS WG within this framework, a series of workshops on the safety test and evaluation of ITS, and definition of priority research problem statements. Recommendations are provided to address the formidable challenges facing the WG. It is anticipated that increased public and government concerns about ITS safety in the future will stimulate increased interest, expectation and funding of harmonized research. For the covering abstract see ITRD E111577.