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This paper deals with a comparative study between reluctance (REL), permanent magnet assisted reluctance (PMAREL), and surface mounted permanent magnet (PM) synchronous machines with rotor eccentricity. Static, dynamic, and combined eccentricity cases are considered. For the sake of generality, this comparison is carried out at different levels of air-gap flux density, as different current angles, different PM materials, and different number of magnetic poles. Additionally, different stator windings arrangements, i.e, distributed and fractional slot concentrated windings are taken into account. Besides, different rotor geometries of REL and PMAREL machines are included. As a case of study, 36-slot machine is analyzed, considering three flux barriers per pole; however, the study can be applied to any machine geometry. Due to the structural criticality of the rotor iron ribs of the REL machines, the impact of the eccentricity on the mechanical stress acting on those ribs and the deformation of the rotor is studied. [ABSTRACT FROM AUTHOR]

Synchronous reluctance machine has high flux density fluctuations in the iron due to the high harmonics results from the rotor anisotropy. Thus, an accurate computation of the iron losses is of paramount importance, especially during the design stage. In this paper, a nonlinear analytical model considering the magnetic iron saturation and the slotting effect is proposed. The model estimates accurately the iron losses at a wide range of operating speed. In addition, the accuracy of the nonlinear model when the machine is highly saturated, i.e., when it works along the maximum torque per ampere (MTPA) trajectory, is presented and verified. The model presented is general and can be applied to other configurations. A 36-slot four-pole machine, with three flux-barriers per pole is considered as a case study. Finite element analysis is used to validate the results achieved by means of the nonlinear analytical model. Furthermore, an experimental setup is built to validate the simulation results. [ABSTRACT FROM AUTHOR]

Introduction: The cornerstone of treatment for endometrial carcinoma is total abdominal hysterectomy and bilateral salpingo-oophoprectomy. Pelvic lymphadenectomy, with or without para-aortic lymphadenectomy, plays an important role in the surgical staging of endometrial carcinoma, and provides more accurate prognostic information.Aims: We aimed to evaluate the value and techniques for SLN mapping in early stage endometrial cancer with low risk for lymph node metastasis and whether selective or systematic lymphadenectomy is needed according to the results of proposed algorithm.Method: Between June 2016 and June 2017, 120 patients with early stage endometrial cancer with low risk for nodal metastasis underwent surgical staging. Patients were classified equally according to SLN mapping technique used for injecting the methylene blue dye. Group A included hysteroscopic guided methylene blue injection, Group B included transcervical injection, Group C included subserosal uterine injection and Group D included combined transcervical and subserosal injection. Blue lymph nodes and enlarged suspicious whether stained or non stained ones were dissected for frozen section evaluation done then bilateral pelvic node dissection was done and tissues were sent for pathological examination.Results: Clinical and pathological SLN detection were more with hysteroscopic technique than others and pathological detection was lower than clinical detection in all techniques. Metastatic disease was more common in nodes with suspicious appearance. About 10% of negative suspicious and mapped nodes were associated with positive other nodes for metastasis.Conclusion: SLN in endometrial cancer has a role in staging of endometrial cancer with best technique for detection, hysteroscopic guided blue dye injection. SLN can be used in patients with low risk for lymph node metastasis for selective lymphadenectomy. Blue dye labelling using methylene blue dye is good in low resource countries as it is cheap. We recommended the following algorithm for surgical staging in early endometrial cancer with better results than using SLN alone. Stage I type 1, grade 1,2 endometrial cancer should undergo surgical staging with initial evaluation of the peritoneum which if affected, it is stage III with no need for lymphadenectomy. Then, dissection of the blue and suspicious nodes which if any is positive on frozen section, selective same side pelvic and paraaortic nodal dissection should be done. If they are negative, no need for lymphadenectomy. This approach can help patients to avoid the side effects associated with a complete lymphadenectomy. The higher rate of detection using this algorithm is related to combining the suspicions nodes with the stained ones. [ABSTRACT FROM AUTHOR]

This paper deals with an analytical model of reluctance synchronous motor, able to consider both stator slotting effect and magnetic saturation in the stator and rotor iron paths. It joints the field distribution at the air gap to a lumped-parameter magnetic network. Local saturation factors are defined so as to adjust the flux-density distribution. The analytical approach exhibits great potentiality, since it is a formulation based on an harmonic study, and it is easily adaptable to any motor geometries. As an example, 36-slot 4-pole machine is analyzed, considering three flux barriers per pole. Finite element analysis confirms the results achieved by means of the analytical model. [ABSTRACT FROM PUBLISHER]

This paper deals with an improved analytical model of synchronous reluctance (REL) machine considering rotor eccentricity. This model considers the magnetic saturation in the iron parts of both the stator and the rotor. This saturation results from the actual B–H characteristic of the iron. In addition, the slotting effect is considered in the analytical model. The unbalanced magnetic force (UMF) on the rotor is accurately estimated. Furthermore, the impact on the estimated UMF due to the slotting effect and the magnetic saturation is studied. Both static and dynamic eccentricity cases are considered. As an example, a four-pole 36-slot REL motor with three flux-barriers per rotor pole is considered. Experimental measurements confirm the results achieved by means of both finite-element analysis and the improved analytical model. [ABSTRACT FROM AUTHOR]

Ultrafast electron diffraction is used to probe the lattice dynamics of femtosecond laser-excited antimony thin film. The temporal hierarchies of the intensity and position of diffraction orders are monitored. The femtosecond laser excitation of antimony film was found to lead to initial compression after the laser pulse, which gives way to tension vibrating at new equilibrium displacement. A damped harmonic oscillator model, in which the hot electron-blast force contributes to the driving force of oscillations in lattice spacing, is used to interpret the data. The electron–phonon energy-exchange rate and the electronic Grüneisen parameter were obtained. [ABSTRACT FROM AUTHOR]

This paper describes a procedure for a practical synthesis of both a synchronous reluctance motor and a permanent magnet assisted synchronous reluctance motor. The procedure is completely analytical, yielding a rapid drawing of the motor geometry, taking into account both magnetic and mechanical considerations. From the application requirements, the external volume of the motor is computed. The further practical needs, such as maximum outer space, maximum available length, existing stator lamination, and so on are considered. Then, the design of the rotor geometry is carried out. The PM size is determined considering the demagnetisation limit according to the maximum current loading. [ABSTRACT FROM AUTHOR]

In the permanent magnet (PM)-assisted reluctance motors, low-energy PM, such as Ferrite PM, is used to get a cheap rotor. As far as the design choices are concerned, the PM width has to be selected so as to achieve the desired air-gap flux density at no-load condition and the PM thickness has to be selected to avoid the demagnetization of the PM under full-load conditions. This paper presents a practical analytical approach to compute PM width and thickness according to a given air-gap flux density and stress on the PM itself. Two approaches based on a complete model and a simplified model are considered and compared. As an example, a 36-slot 4-pole machine is designed. Finite element analysis confirms the results achieved by means of both analytical analyses. [ABSTRACT FROM PUBLISHER]

This paper describes a procedure for a practical synthesis of both a synchronous reluctance motor and a permanent magnet assisted synchronous reluctance motor. The procedure is completely analytical, yielding a rapid drawing of the motor geometry, taking into account both magnetic and mechanical considerations. From the application requirements, the external volume of the motor is computed. The further practical needs, such as maximum outer space, maximum available length, existing stator lamination, and so on are considered. Then, the design of the rotor geometry is carried out. The PM size is determined considering the demagnetisation limit according to the maximum current loading. [ABSTRACT FROM AUTHOR]

In this paper, a coupled experimental–mathematical inverse problem based methodology for the detection of interturn faults in an asynchronous induction machine is presented. The fault detection is accomplished by interpreting well-defined measurements into the machine mathematical model. First, the studied machine is modeled by means of a dynamic state-space model in the $abc$ reference frame. This model simulates the machine behavior under healthy and faulty cases in both transient and steady-state conditions. The signature of the interturn fault is captured using the magnetic pendulous oscillation technique. The proposed inverse problem is validated numerically and experimentally. The results show the robustness of the proposed scheme against the measurement noise. [ABSTRACT FROM AUTHOR]

Referring to the analysis of the impact of the eccentricity on a synchronous reluctance motor presented in the companion paper (Part I), a comparison is carried out between rotors with symmetric and asymmetric flux-barriers. As an example, a four-pole machine with one or two flux-barriers per pole is used. In addition, the analysis is also applied to motors with fractional-slot coil windings. Both single- and double-layer windings are considered. As an example, a six-slot four-pole machine with concentrated windings and 36-slot four-pole machine with distributed windings are compared. The analytical model which is proposed in Part I is used to predict the machine performance. A finite-element analysis confirms the results achieved by means of the analytical model. [ABSTRACT FROM AUTHOR]

In recent years, there is a growing interest for synchronous reluctance machines. This is due to their high torque density, flux-weakening operation capability, and high fault-tolerance capability. This paper deals with the analysis of a synchronous reluctance machine when eccentricity occurs. Both static and dynamic eccentricity are considered. An analytical model to predict the machine performance is described. As an example, a four-pole reluctance machine is analyzed, considering single, as well as multi flux-barriers per pole. The finite-element analysis confirms the results achieved by means of the proposed analytical model. [ABSTRACT FROM AUTHOR]

The synchronous reluctance motor works under heavy saturation. This paper presents a nonlinear analytical model of the reluctance machine, which is used to derive both average and torque harmonics as a function of the rotor geometry. Maps showing the torque harmonics as a function of the rotor barrier angles are derived. These maps are useful tools for the machine designer to get a proper rotor geometry. The torque maps are compared with those obtained from both linear analytical and finite element models. The maps computed analytically show good agreement with those derived by means of finite element analysis, and they are obtained in a much smaller computing time. [ABSTRACT FROM AUTHOR]

This article presents an accurate analytical model (AM) for synchronous reluctance machine (SynRM) that incorporates the effect of stator slots on the air gap flux density and torque waveforms. From the formulation of magnetic potential in the air gap for both the stator and rotor, the flux density is obtained, considering the first harmonic of the flux density and the electric loading, the average torque is calculated using the Lorentz’s force. The ripple torque is obtained from the energy stored in magnetic circuit. The method is developed for a rotor with one flux barrier per pole and then extended to a larger number of barriers. To validate the results obtained by the AM proposed finite element analysis have been carried out. Several comparisons have been derived considering different rotor positions as well as different harmonic orders, and the pros and cons of the method are highlighted. The model performs fast and can predict results with high accuracy, and can be adopted to speed up the preliminary design and optimizations of this type of motors, with respect to finite element. In addition, from the analytical expressions it is possible to obtain all the correlations between electrical, magnetic, and geometrical characteristics of the machine, with the advantage of enabling a faster machine design. [ABSTRACT FROM AUTHOR]

• Multicharged carbon ions are produced from femtosecond laser ablation. • Up to C6+ ions are produced from a laser plasma. • Carbon ion signal fits a shifted Maxwell-Boltzmann distribution. • External electric field along the plasma expansion increases ion extraction. Carbon ion emission from femtosecond laser ablation of a glassy carbon target is studied. A Ti:sapphire laser (pulse duration τ ~ 150 fs, wavelength λ = 800 nm, laser fluence F ≤ 6.4 J cm−2) is used to ablate the carbon target while ion emission is detected by a time-of-flight detector equipped with a three-grid retarding field analyzer. A strong effect of the laser pulse fluence on the yield of carbon ions is observed. Up to C6+ ions are detected. The carbon ion time-of-flight signal is fit to a shifted Maxwell-Boltzmann distribution and used to extrapolate the effective plasma ion temperature T ieff = 6.9 eV. Applying an external electric field along the plasma expansion direction increases ion extraction, possibly due to the retrograde motion of the plasma-vacuum edge. [ABSTRACT FROM AUTHOR]

This paper presents a novel framework comprises of a Propositional Satisfiability (SAT) encoder and solver. The framework responsible for generating and proving a simplified SAT-based formula of digital circuits for Automatic Test Pattern Generation (ATPG) proposes. The parallel algorithms introduced in this work are aimed at both combinational and sequential circuits and optimized on NVIDIA General-Purpose Graphics Processing Unit (GPGPU) paradigm. The SAT encoder presents an efficient method to apply the Boolean Constraint Propagation (BCP) on-the-fly while the generation is running on the GPU. The simplified formula is further proved for satisfiability using an improved parallel solver on GPU. The proposed encoder executes 93 times faster compared to the sequential counterpart. The test generation algorithm using the GPU-accelerated framework delivers about 5.86 speedup on an average compared to the state-of-the-art Lingeling solver. Moreover, the SAT encoder reduced the run time for fault detection by 6.53 and 11.42% on an average when applied to the proposed and the conventional CUD@SAT solvers, respectively, offering promising related work for the future research. [ABSTRACT FROM AUTHOR]