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Summary: The X chromosome shows a special interaction between demographic factors and genetic variation, and the analysis of X‐linked genomic variation can therefore provide insights into the unique effects of demography and selection on the horse genome that cannot be readily detected by autosomal markers. Debao (DB) ponies have experienced intense selective pressure for the development of their small stature (<106 cm at adult height). To identify selective sweeps on the X chromosome of the DB pony, we performed a genome‐wide scan of three Chinese horse breeds using an Equine SNP70 BeadChip. Using Yili and Mongolian horses (>134 cm at adult height) as reference groups, both FST and XP‐EHH revealed that five regions on the X chromosome were under strong selection, resulting in 95 overlapping genes. Seven of these genes, SMS, PHEX, ACSL4, CHRDL1, CACNA1F, DKC1 and CDKL5, are involved in bone development, growth hormone secretion and fat deposition. The region showing the strongest selection pressure was located at the position of 86.6–87.5 Mb. The subsequent genome‐wide association analysis of the adult height of three Chinese horse breeds detected the two most significant SNPs in the same region, and these two SNPs overlapped with the gene CHRDL1. As a member of the bone morphogenetic protein (BMP) superfamily, CHRDL1 antagonizes the function of BMP4 and plays an important role in embryonic bone formation and cartilage generation. Our results provide new insights into the X‐linked selection in Chinese Debao pony. [ABSTRACT FROM AUTHOR]

This paper proposes a coordinated positioning control network for three direct drive, linear switched reluctance machines. To obtain the optimized network control parameters, the distributed linear quadratic regulator is applied. Different communication topologies are studied for both the dynamic tracking and the coordination performance of the network. Experimental results demonstrate that an absolute static tracking precision of 20~\mu \textm can be achieved from the “cycle” communication topology and an absolute static coordination precision of 11~\mu \textm can be obtained from the “path” communication topology. [ABSTRACT FROM AUTHOR]

In this paper, a novel direct drive, bilateral planar switched reluctance generator (BPSRG) is developed for 2-D wave energy conversion with a mixed type of flux circulation. The proposed BPSRG has longitudinal flux type of the magnetic circuit on one direction and transverse flux-type magnetic circulation for the other perpendicular direction. The characteristics of the magnetic flux and static inductance are calculated for the BPSRG based on the 3-D finite-element method, in order to ensure negligible coupling effect between any phases. Theoretical model of the BPSRG is derived, and parameters that impact the open-loop operation performance of the power generation are analyzed, optimized, and supported by experimental results. [ABSTRACT FROM AUTHOR]

A fuzzy position controller is employed for the linear switched reluctance motor. Performance comparison between the fuzzy controller and a proportional-differential (PD) controller is carried out. Under the PD controller, the absolute steady-state error is 44.5 ~211.5 μm under normal condition and 1157–1212 μm under sustained time-variant disturbance circumstance, respectively. The absolute steady-state error of 3 μm and 9 μm can be achieved under the fuzzy controller in the normal and sustained disturbed circumstance. Experimental results demonstrate that the position tracking performance from the proposed algorithm is superior to the conventional PD control strategy, both in normal circumstance and disturbance environment. [ABSTRACT FROM AUTHOR]

In this paper, to enhance the machine performance and realize a high-precision position control performance, a dual-loop position controller is employed for the asymmetric bilateral linear hybrid switched reluctance motor (ABLHSRM). Machine characteristics are investigated by finite-element method. The dual-loop controller is constructed by employing a tradition proportional–integral differential velocity controller as the inner loop and a fuzzy proportional differential (PD) controller for the outer loop. Experimental results demonstrate that both the position control performance and the velocity control performance under the dual-loop control algorithm are superior to the single-loop PD position control strategy. An absolute steady-state error of 4 \mu \textm can be achieved under the dual-loop control strategy. Performance comparison from the ABLHSRM and its asymmetric bilateral linear switched reluctance counterpart with the same dimensions are carried out. Position tracking results show that the rise time is improved for the proposed ABLHSRM under the proposed control scheme. [ABSTRACT FROM AUTHOR]

A direct-drive generator based on linear switched reluctance principle is investigated for wave energy utilization. Integrated with the sensorless technique, the direct-drive generator has the characteristics of low cost and robustness, and the power generation control system is especially suitable for the operation under hostile working environments since restrictions of physical sensors are eliminated. Simulation analysis based on the finite element methods (FEM) and joint simulation are carried out for performance analysis of the power generation control system, including position estimation, open loop turn-on and turn-off position optimization and closed loop current regulation. Experimental results validate the effectiveness of the position estimation scheme for the sensorless, linear switched reluctance generator based power generation control system. [ABSTRACT FROM AUTHOR]

This paper discusses about the voltage output ripple reduction and error minimization for the direct-drive, linear switched reluctance generator (LSRG)-based wave power generation system. First, the concept of the LSRG-based wave power generation system is studied. According to the characteristics of the LSRG, the suitable drive circuit dedicated to proper current excitation and generation is established. Second, the reasons that cause voltage output ripples are investigated. To reduce the remarkable ripples from phase current commutations, a current distribution function (CDF) is proposed based on the minimized copper loss principle. Third, the dual-loop control strategy with current and voltage as the inner and outer loop is constructed, implemented with the proposed CDF. Theoretical bases of the control strategy are derived. The simulation results prove that the proposed control algorithm is capable of voltage ripple suppression and error reduction within the range of ±0.5 V over the entire operation speed for wave energy extraction, validated by experimental verification. [ABSTRACT FROM AUTHOR]

Core loss is one of the key factors for performance evaluation of switched reluctance machines. In this paper, core loss analysis of the planar switched reluctance motor (PSRM) is calculated based on the 3-D time-stepping finite element methods. The numerical analysis for the computation of the core loss is discussed, also its transient and average core loss in the mover and the stator are calculated. The corresponding experiments of measurement loss for a PSRM prototype are conducted and the results validate the accuracy from the numerical analysis. It can be concluded that core loss dominates around the corner of the mover and stator cores. [ABSTRACT FROM AUTHOR]

An integrated rotary–linear machine based on switched reluctance principle is investigated. The characteristics of the motor are analyzed by finite-element methods, with particular emphasis on the coupled magnetic paths. Results from numerical calculation are verified by the hardware experiment. The simple yet effective decoupling algorithm for the independent position control of both rotary and linear axes is proposed. Implemented with the proportional–integral-differential algorithm, the motor is capable of high-precision rotary and linear position tracking with the steady error within 0.3^\circ and 10~\mum, respectively. [ABSTRACT FROM AUTHOR]

A novel double-sided electric asymmetric linear switched reluctance motor (LSRM) is proposed in this paper. The features of the proposed linear machine are that mover teeth and stators are not exactly identical according to the axis of the moving platform. This machine structure ensures that the alleviation of motor saturation magnetization effect and a higher thrust force output can be derived from the asymmetric LSRM. A thorough magnetic analysis is carried out for performance prediction of the machine, and results are compared to a symmetric LSRM counterpart. Both theoretical and finite-element methods results prove the priority of the asymmetric LSRM with higher force-to-volume ratio and better acceleration performance. Experimental results from the machine prototype validate the design of an asymmetric LSRM with yoke length of 12 mm. [ABSTRACT FROM PUBLISHER]

A transverse-flux tubular linear machine with novel gear-shaped teeth for high force density is proposed. The teeth can be formed by silicon steel laminations or permanent magnets for a tubular linear switched reluctance or tubular linear hybrid motor. With the unique improved teeth structure and short magnetic circulation paths, larger propulsion force output can be obtained with reduced mover weight and volume. Simulation based on finite element method (FEM) verifies the validity of the proposed machine design. The proposed machines are compared with other transverse-flux linear machines. Results show that the proposed tubular motors exhibit better output performance with a higher force-to-volume ratio. [ABSTRACT FROM AUTHOR]

An improved force distribution function (FDF) of linear switched reluctance motors (LSRMs) based on nonlinear inductance modeling for force ripple minimization and smooth speed operation is proposed. Nonlinear inductance profile is divided into three segments with a K factor that depicts current effect on inductance of the LSRM. Speed controller based on the proposed FDF and the nonlinear inductance model is constructed. Both simulation and experimental results verify the proposed FDF with the nonlinear inductance modeling effectively reduce force ripples with uniform speed response. [ABSTRACT FROM AUTHOR]

This paper presents a novel two-dimensional (2-D) planar switched reluctance motor (PSRM) for position control applications. The proposed 2-D planar motor has the advantages of simple mechanical construction, high reliability, and the ability to withstand hostile operating conditions. Due to the unique structure of the planar motor's magnetic circuit, there is very little coupling between the X- and Z-axis, and no decoupling compensation is needed. It is expected that this innovative SR planar motion system will be an ideal replacement for traditional X-Y tables in industrial automation applications. [ABSTRACT FROM AUTHOR]

A novel planar motor based on the switched reluctance (SR) principle has been developed. This motor has the advantages of simple structure, low cost and ease of manufacture. The motor is highly reliable and can work in hostile working environments. However, in many industrial applications, the motor's performance is subject to practical constraints, such as mechanical noise, load disturbance and friction. The motor cannot cope with these difficulties under classical PID control scheme. Therefore an auto-disturbance rejection control (ADRC) strategy is proposed to overcome these problems. An ADRC velocity control strategy is implemented on the planar motor, and its performance is then compared with a classical PID controller. Experiment results demonstrate that the motor is more resistant to disturbances under this new control scheme. It confirms that ADRC is an effective solution to overcome the inherent control problems of the SR planar motor. It is expected that the same method can be applied to other SR machines with the same promising results. [ABSTRACT FROM AUTHOR]

Compares the bioavailability of trace metals, chromium and iron bound with natural colloids of different origins and sizes to marine bivalves. Isolation of colloids; Radiolabeling of colloids; Uptake of colloidal metals by bivalves.

This paper discusses the tracking coordination of a linear switched reluctance machine (LSRM) network based on a global feedback control strategy with a full-state observation framework. The observer is allocated on the follower instead of the leader to form a leader--follower--observer network, by utilizing the leader as the global feedback tracking controller and the observer as the observation of the full states. The internal model compensator (IMC) is applied to the leader for the improvement of the network performance. The full-state information of the LSRM network is reconfigured by the output of the LSRM where the observer is located to provide necessary feedback information to the leader. Then, the controllability and observability of the leader--follower--observer network with the IMC are inspected, serving as a basis for the design of the global controller with the IMC and full-state observer. Experimentation verifies the effectiveness of the proposed network control scheme and the results demonstrate that both the absolute and the relative accuracy can be simultaneously improved, compared to the LSRM network with only the consensus algorithm and no global feedback mechanism. [ABSTRACT FROM AUTHOR]

An adaptive high-precision position control algorithm with online system identification is implemented onto the switched reluctance, two-finger gripper with coupled magnetic paths. Theoretical investigation proves that the magnetic paths from the two fingers are highly coupled. Without the introduction of any decoupling scheme, the position control performance under the proportional integral differential controller and the adaptive controller is inspected and the control results are compared. Experimental results verify that, without introducing any decoupling mechanism, the adaptive controller is capable of independent control of each finger with a high-precision and uniform position control performance. [ABSTRACT FROM AUTHOR]

In this paper, a new rotary-linear switched-reluctance motor with a magnetic decoupled structure is introduced. The rotational motion of the motor, managed by a sliding-mode controller, is coordinated with the proportional-derivation linear motion by using a fuzzy logic block. Consequently, both rotational and linear motions can be realized simultaneously. In addition, the decoupled magnetic paths of the motor in two directions are analyzed by finite-element method, with the force and torque measurements suggesting the feasibility of the motor. Both the simulation and experimental results show that the motor is totally decoupled in the linear and rotary directions. The linear movement and the rotation at the same time validate the effectiveness of the motor design and the proposed control method, with highly accurate responses for the two degrees of freedom movement. [ABSTRACT FROM AUTHOR]

In this paper, an approach combining current pulses injection and fuzzy logic observer to measure the air gap length of linear machines is proposed. A polymer enclosed by a coil is produced and selected as the test object. The characteristics and production process for the polymer is introduced and its magnetic feature has been studied. Injecting current pulses is used to calculate the self-inductance of the coil fixed on the cores that is directly influenced by the air gap length from the polymer. By using a fuzzy logic observer, the air gap length can be estimated precisely according to the variations of the self-inductance. Experimental results show the effectiveness of the proposed measurement method and the results prove that the proposed method is suitable for the air gap measurement for linear machines. [ABSTRACT FROM AUTHOR]

This paper investigates a distributed, coordinated motion control network based on multiple direct-drive, linear switched reluctance machines (LSRMs). A hierarchical, two-level synchronization control strategy is proposed for the four LSRMs based motion control network. The high-level, reference signals agreement algorithm is first employed to correct the asynchronous behaviors of the position commands. Then, the low-level tracking synchronization method is applied for the collaborative position control of the four LSRMs. The proposed two-level, fault-tolerant control strategy eliminates the asynchrony of the reference signals and it also guarantees the coordinated tracking control performance of the four LSRMs. Experimental results demonstrate that effective coordinated tracking control can be ensured, based on the successful agreement of reference signals and an absolute tracking error falling within 2 mm can be achieved. [ABSTRACT FROM AUTHOR]

The coordinated tracking control for the group motion control system based on three direct-drive double-sided linear switched reluctance motors (LSRMs) is investigated in this paper. The system construction for the proposed coordinated tracking system is elaborated, including the unit system and group system design, communication configuration among unit systems, and stability and performance analysis of the group system. The coordinated control performance is concentrated on three identical LSRMs with different communication topologies. Experimental results demonstrate that necessary bidirectional interactions between the unit systems contribute to the coordination performance. The maximum dynamic tracking error within ±0.4 mm can be achieved under the sinusoidal reference of 30-mm amplitude and 0.2-Hz frequency. [ABSTRACT FROM PUBLISHER]

In planar switched reluctance motors (PSRMs), the electromagnetic force ripple minimization is important to reduce the noise and vibration for high-precision motions. In this paper, an improved PSRM by optimization design for minimization of the electromagnetic force ripple is proposed. The structure, principle, and mathematical model of the PSRM are clarified. Based on Ansoft Maxwell, optimization design of the PSRM is performed by improved structure with smaller pole pitch and incremental number of mover poles. Experiments of the improved PSRM are implemented based on dSPACE. The experimental results verify that the improved PSRM effectively reduces electromagnetic force ripple with planar trajectory tracking. [ABSTRACT FROM AUTHOR]

Mn0·4Zn0·6NdxFe2-xO4/polyaniline (PANI) nanocomposites with magnetic properties were prepared by in situ polymerisation of aniline in the presence of Mn0·4Zn0·6NdxFe2-xO4 nanoparticles. The structure and morphologies of nanocomposites were characterised by X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM). X-ray diffraction analysis shows that the size of Mn0·4Zn0·6NdxFe2-xO4 nanocomposites increases with the increase in the Nd doped amount. The optimum doped amount of Nd was 0·075, and the optimum calcination temperature was 850°C. The ferrite particles are well embedded in PANI chains. The FTIR results further prove that the Nd doped manganese-zinc-ferrite/PANI composites have been synthesised. Images (TEM) showed that the nanocomposites presented a spherical structure with a magnetic core of Mn0·4Zn0·6NdxFe2-xO4 and a conducting shell of PANI. The results showed that the electromagnetic properties of the Mn0·4Zn0·6NdxFe2-xO4/PANI composites were related to the mass ratio of PANI, the amount of Nd, the calcination temperature and the precipitation time. [ABSTRACT FROM AUTHOR]

A controller design methodology to regulate the output voltage of a phase-shifted resonant converter is presented. The design objective is to overcome the highly nonlinear characteristics of the phase-shifted resonant converter observed when the load is unknown. The control goal is to maintain the output voltage at desired values in the presence of large load perturbations by varying the phase angle of the full-bridge converter. The controller is derived using passivity theory which ensures that the closed-loop system is exponentially convergent and that only a single output feedback is required. An adaptive version is deduced to estimate the output load resistance for the passivity control. This feature allows the use of an extra output current sensor to be avoided. The structure of the controller derived using passivity theory is very simple. Laboratory experiments performed using a digital signal processor system confirm the robustness of the converter with the passivity-based controller. [ABSTRACT FROM AUTHOR]