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Two types of wedge-shaped CsI(Tl) crystals were designed to be placed behind an annular double-sided silicon detector to identify light charged-particles with the Δ E − E method. The properties of the CsI(Tl) detectors with different shapes and sizes were investigated using an α source and a radioactive beam of 15C. The larger crystal was found to have better energy resolution, smaller light output non-uniformity, as well as better particle identification capability, and was finally adopted to form the Δ E - E telescope. The performance of the two types of CsI(Tl) crystals are interpreted based on Geant4 simulation results.

To make the voltage of and the power factor of AC side adjustable, according to the working principle of the three-phase voltage source PWM rectifier,establish the mathematical model of DC regulated power supply, introduce the space voltage vector modulation technology, and build its circuit model based on SVPWM control on the Matlab/Simulink software platform, The simulation results show that this control strategy is feasible.

The composition of Qinling Mountain rock is studied using laser induced breakdown spectroscopy for the first time. Elements Ca, Mg, Cu, Fe, C, Na, Si, Al, Ti, K and Mn are identified qualitatively. Using an improved iterative Boltzmann plot method, the electron temperature of 16,825 K is inferred with Ca I lines at 422.67, 428.30, 443.49, 445.48, and 585.74 nm, while the ionic temperature of 15,587 K is obtained with Ca II lines at 393.37, 396.85, and 370.60 nm. The electron number density of 1.49 10 cm is inferred from the Stark broadened profile of Ca I 422.67 nm averaged with 10 single spectra. The laser-induced rock plasma is verified to be in local thermodynamic equilibrium and to be optically thin based on the experimental results.

Capacitor switching transient is one of the most commonly encountered power quality disturbances. Measuring and identifying these transients remains a challenge as the characteristics depend on the system parameters, capacitor ratings and makeup of the connected loads. This paper describes a systematic approach to design an automated system for identifying such transients. It relies on the belief that some of the system and component parameters are either known or can be determined, and thus can be used to develop the necessary pattern for identification and discrimination. However, identification also needs to be robust against uncertainties in these parameters. The proposed method combines the techniques of wavelet transform, rank correlation and fuzzy logic to account for the uncertainties. Dynamic simulations were undertaken to verify the method and to illustrate its robustness when dealing with various uncertain transient characteristics. It is shown to be capable of identifying transients caused by switching of both isolated and back-to-back capacitors.

Follicle-stimulating hormone (FSH), a glycoprotein secreted by the anterior pituitary, can regulate ovarian function through the FSH receptor (FSHR). To evaluate the effects of the FSHR gene on reproductive traits in pigs, polymorphisms in exon 10 of the FSHR gene were observed by polymerase chain reaction-single-strand conformation polymorphism, and 3 single nucleotide polymorphisms (C1491T, G1885A, and C1977T) in exon 10 of the porcine FSHR gene, and 3 genotypes (AA, AB, and BB) for C1491T and 2 haplotypes (D and E) for G1885A and C1977T were identified. Further analysis of single nucleotide polymorphism genotypes associated with reproductive traits including total number born (TNB) and number born alive (NBA) was carried out in 3 pig populations including Berkshire, Wannan Black (a Chinese indigenous pig breed), and BW pigs (two-way crossbred pigs produced from Berkshire ♂ and Wannan Black pig ♀). The results showed that the TNB and NBA of Wannan Black pigs with the AB genotype were significantly higher than in AA genotype sows (P0.01) in multiparity sows and all parities. The TNB and NBA of Berkshire pigs with the DE genotype were significantly higher than the DD and EE genotype sows (P0.01) in gilts, sows and all parities. Overall, TNB and NBA from the 3 identified genotypes was DEDDEE. The results showed that polymorphisms in exon 10 of the FSHR gene had a significant effect on litter size traits of Wannan Black and Berkshire pigs. These results can be applied for marker-assisted selection in the 2 swine breeds.

The present paper obtains the exact solutions to the time-dependent supersymmetric two-level multiphoton Jaynes-Cummings model and the Chiao-Wu model that describes the propagation of a photon inside an optical fiber. On the basis of the fact that the two-level multiphoton Jaynes-Cummings model possesses a supersymmetric structure, an invariant is constructed in terms of the supersymmetric generators by working in the sub-Hilbert-space corresponding to a particular eigenvalue of the conserved supersymmetric generators (i.e., the time-independent invariant). By constructing the effective Hamiltonian that describes the interaction of the photon with the medium of the optical fiber, it is further verified that the particular solution to the Schrodinger equation is the eigenfunction of the second-quantized momentum operator of photons field. This, therefore, means that the explicit expression (rather than the hidden form that involves the chronological product) for the time-evolution operator of wave function is obtained by means of the invariant theories.

Short duration voltage variation is one of the most commonly encountered power quality disturbances. The severity is generally determined by the remaining voltage RMS magnitude and the duration of the disturbance. These are generally determined through the RMS measurement method, which at times faces difficulties especially with variations of very short duration. This paper proposes an alternative technique to effectively characterize voltage variations of all durations. It uses wavelet analysis to zoom into a high frequency band for the time information, and the fundamental frequency band for the magnitude change. It is shown to be effective even for very short interruption, which is difficult to determine using the RMS method. Compared to other wavelet methods, its low computational requirement makes it suitable for real-time application. Dynamic simulations were used to demonstrate the capability of this method.

At higher Hertz pressures, the wear of boronized 45C steel revealed a three-period behaviour, i.e., steady state wear, accelerative wear and rapid wear. The wear ressistance greatly increased with increasing substratum hardness. It was proposed that the accelerative wear was due to the contact fatigue and hardening the substratum would increase the contact fatigue strength so as to increase the wear ressistance.