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With high surrounding temperatures, winding resistance increases and thus lowers the operational efficiency of a motor. To meet the large application requirements and conform with the ever-increasing energy-efficiency regulations for pump equipment in the metals industry, consistent efforts have focused on producing single-phase motors that can deliver superior performance at a low cost. Because the steady-state rotational speed is synchronized and no driver circuit is required, a direct-on-line synchronous reluctance motor is a potentially viable alternative to the commonly adopted induction motors. Its inherently simple structure and comparably low operational speed necessitate a challenging structural design for accomplishing the high-efficiency objectives of pump applications. These challenges and their potential solutions are reported in detail. By employing a systematic design scheme and including thermal concerns of the performance, a competitive high-efficiency single-phase direct-on-line synchronous reluctance motor for pump applications in various metal industry equipment was offered. [ABSTRACT FROM AUTHOR]

To meet the severe operating conditions in the metal industry, more thorough design and operational assessments about those implemented electric motors for specific applications must be emphasized. With its inherent robust structure, the induction motor is generally adopted to fulfill such driven objective. However, due to global warming and energy conservation concerns, those strictly enforced regulations have potentially increased the complexity and cost of high efficiency induction motor. Since the synchronous reluctance motor (SynRM) has relatively simpler structure with no copper loss in its rotor, it is a very attractive alternative for accomplishing the high-efficiency objectives of those common hoist, punch, roller, and pump applications. In addition, to eliminate drive circuits that can further reduce the overall system construction costs, the rotor barriers of the SynRM can be equipped with direct-on-line capability (DOL_SynRM) with conductors filled in. The impacts to the operational performance of these DOL_SynRMs for different applications will all be thoroughly investigated. The competitive high-efficiency DOL_SynRMs for driving various metal industry equipment can thus be offered. [ABSTRACT FROM AUTHOR]

Attention-deficit/Hyperactivity disorder(ADHD) is a common neurodevelopmental disorder among children. Traditional assessment methods generally rely on behavioral rating scales (BRS) performed by clinicians, and sometimes parents or teachers. However, BRS assessment is time consuming, and the subjective ratings may lead to bias for the evaluation. Therefore, the major purpose of this study was to develop a Virtual Reality (VR) classroom associated with an intelligent assessment model to assist clinicians for the diagnosis of ADHD. In this study, an immersive VR classroom embedded with sustained and selective attention tasks was developed in which visual, audio, and visual-audio hybrid distractions, were triggered while attention tasks were conducted. A clinical experiment with 37 ADHD and 31 healthy subjects was performed. Data from BRS was compared with VR task performance and analyzed by rank-sum tests and Pearson Correlation. Results showed that 23 features out of total 28 were related to distinguish the ADHD and non-ADHD children. Several features of task performance and neuro-behavioral measurements were also correlated with features of the BRSs. Additionally, the machine learning models incorporating task performance and neuro-behavior were used to classify ADHD and non-ADHD children. The mean accuracy for the repeated cross-validation reached to 83.2%, which demonstrated a great potential for our system to provide more help for clinicians on assessment of ADHD. [ABSTRACT FROM AUTHOR]

To meet different loading requirements in the metal industry, special attention must be paid to the operational performances and start-up characteristics of those electric motors implemented for desired driven applications. However, because of the global warming and energy conservation concerns, the enforced operational regulations have increased the complexity of those commonly applied induction motors for supplying the desired equipment driven forces. By adopting the same stator, the synchronous reluctance motor (SynRM) can be achieved with properly redesigned rotor structure of an induction motor. Due to its robust structure and lack of secondary copper loss, it is very competitive for the related hoist, punch, roller, and pump applications. Furthermore, by inserting adequate ferrite permanent magnets and conductors into the rotor barriers, composition designs of the direct-on-line SynRMs (DOL_SynRMs) will also be proposed. The operational characteristics of the DOL_SynRMs for fulfilling different specifications will all be thoroughly investigated and confirmed by experimental measurements. The DOL_SynRM structures that can provide potential alternatives for related high-efficiency metal industry-driven applications can thus be validated. [ABSTRACT FROM AUTHOR]

To meet the higher operational efficiency regulations of electric motors due to energy-conservation concerns, specific design efforts have been dedicated to those motors for different industrial application requirements. Since the synchronous reluctance motor (SynRM) is generally designed based on the same stator structure as that of the induction motor and operated at synchronous speed, whereas no electrical contact to its rotor, it is capable of providing a robust structure and no rotor copper loss. Such features are very attractive for the related hoist, punch, roller, and pump applications that are commonly adopted in the metals industry. By equipping adequate power factor correction and line-start capabilities, the detailed designs and performance analyses of the SynRMs with a common rotor structure composed by laminated electrical steels will be proposed. Based on this common rotor structure, the operational characteristics of the SynRMs for fulfilling different specifications will all be thoroughly investigated. Confirmed by experimental validations, valuable guidance for related SynRM constructions and applications can thus be provided for metals industry and motor designers. [ABSTRACT FROM AUTHOR]

To meet the increasingly stringent regulations on operational efficiencies of electric motors, efforts have been devoted to design and construct motors with less power losses. Without the need of rotor conductors, and hence, no secondary copper loss, the feasibilities of applying synchronous reluctance motor (SynRM) have attracted many attentions on the related industries. Since the operation of SynRM is mainly based on the reluctance torque, appropriate electromagnetic steel selections for the motors will be the key factors. To adequately evaluate the performance of SynRM, with the available magnetization and hysteresis characteristics of the commercial steel sheets, the SynRMs that are composed of different electromagnetic steels at various operational specifications will be thoroughly investigated. From theoretical analyses of the selected SynRMs by different stator and rotor material compositions along with experimental validations, valuable guidance for related SynRM constructions and operations can thus be provided for steel manufacturers and motor designers. [ABSTRACT FROM PUBLISHER]

To achieve relatively lower costs and higher operational efficiencies, without adopting permanent magnets or rotor conductors, the synchronous reluctance motor (SynRM) has received more and more attentions as a competitive solution recently. To establish a rational guidance for the related designs and constructions, this paper is aimed to present the thorough performance impact assessments of SynRMs that are composed of different electromagnetic steels at various operational specifications. Based on the magnetization and hysteresis characteristics of the steel sheets, variations of the average torques, torque ripples, and iron losses by using different stator and rotor materials are investigated, and some valuable comparison results can be provided for designers and engineers in the related motor and metal industries. [ABSTRACT FROM AUTHOR]

Although it has been widely known that the cutting process of electrical steel brings deterioration effects to magnetic properties, it is still unclear how to evaluate the quality of the cutting process effectively. This paper investigates the performance degradation due to the punching process based on a needle probe instrument that incorporates three needle probes arranged in a way to pick up the flux around the area of the cutting edge and the flux of the unaffected center area. The amount of performance degradation can be obtained by comparing the edge and the center flux values. 50CS1300 samples with different punching clearances were produced, and measurement results were demonstrated. The power conversion losses imposed by the punching process were evaluated in terms of several measured parameters, including the magnetic flux density, the iron loss, and the copper loss. In addition, how different grain sizes affect the punching performance is also studied in this paper. Two materials with the same iron loss grade but different grain sizes were punched, and their magnetic properties were also examined. [ABSTRACT FROM PUBLISHER]

This paper is aimed to provide the detailed design and operational investigations of synchronous reluctance motors (SynRM) that are commonly assembled by laminated electromagnetic steels. The magnetic flux paths in the SynRM rotors with various barrier and segment compositions will be analyzed, along with the generated motor torque and loss assessments. As the related mechanical cutting and/or punching processes on the rotor steels are required to achieve desired direct- and quadrature-axis reluctance ratios, their impacts to the flux paths due to saturations will also be thoroughly evaluated. Assisted by 3-D finite-element analyses, the results clearly indicated that the additional annealing process on the electromagnetic steel strips must be introduced for these SynRM designs with smaller sizes and higher efficiency requirements. [ABSTRACT FROM PUBLISHER]

With their consistent production line load increments, the possibilities of substation congestion problems in the integrated steel companies are inevitable. To meet these power demands, well-organized system infrastructure expansion plans must be designed in advance. An alternative scheme to alleviate some short-term facility overload problems is to integrate distributed generator units into the system to defer possible congestion. Based on substation operational constraints, systematic guidance for evaluating the optimal location and reliability indices of DG units into the system will be provided for related operations. The proposed scheme can be adopted by steel companies and other industries in determining the installation and integration schedule of DG units and thus defer the required expansions of substation infrastructures. [ABSTRACT FROM PUBLISHER]

To design a stable and fully controllable process for conveying steel plates with less noise, we have extensively investigated the feasibility of incorporating the structure that can provide appropriate extra electromagnetic attraction forces. By implementing appropriate fixed electromagnetic poles on top of the rollers at the run-out table of a steel mill, controllable lift and propulsive forces can thus be provided to drive the movable steel plate to the desired 2-D directions. Based on the stringent operational environment at a steel mill, an online recursive gap detection scheme combined with a real-time fuzzy-based controller has been developed. Realization results showed that the system, being implemented with the proposed fine-tuned processing/control scheme, can supply rapid and accurate online 2-D controls onto the steel plates and thus fulfill the design and operational objectives. [ABSTRACT FROM AUTHOR]