THE FEKETE-SZEG?INEQUALITY AND SUCCESSIVE COEFFICIENTS DIFFERENCE FOR A SUBCLASS OF CLOSE-TO-STARLIKE MAPPINGS IN COMPLEX BANACH SPACES

Let C be the familiar class of normalized close-to-convex functions in the unit disk.In[17],Koepf demonstrated that,as to a function■in the class C,■By applying this inequality,it can be proven that‖a3|-|a2‖≤1 for close-to-convex functions.Now we generalized the above conclusions to a subclass of close-to-starlike mappings defined on the unit ball of a complex Banach space.

APPLICATION OF WEIGHTED NONOSCILLATORY AND NON-FREE-PARAMETER DISSIPATION DIFFERENCE SCHEME IN CALCULATING THE FLOW OF VIBRATING FLAT CASCADE

A dual-time method is introduced to calculate the unsteady flow in a certain vibrating flat cascade. An implicit lower-upper symmetric-gauss-seidel scheme（LU-SGS） is applied for time stepping in pseudo time domains, and the convection items are discretized with the spatial three-order weighted non-oscillatory and non-free-parameter dissipation difference （WNND） scheme. The turbulence model adopts q-co low-Reynolds-number model. The frequency specmuns of lift coefficients and the unsteady pressure-difference coefficients at different spanwise heights as well as the entropy contours at blade tips on different vibrating instants, are obtained. By the analysis of frequency specmuns of lift coefficients at three spanwise heights, it is considered that there exist obvious non-linear perturbations in the flow induced by the vibrating, and the perturbation frequencies are higher than the basic frequency. The entropy contours at blade tips at different times display an intensively unsteady attribute of the flow under large amplitudes.

Reduction of Cogging Torque and Electromagnetic Vibration Based on Different Combination of Pole Arc Coefficient for Interior Permanent Magnet Synchronous Machine

Cogging torque and electromagnetic vibration are two important factors for evaluating permanent magnet synchronous machine(PMSM)and are key issues that must be considered and resolved in the design and manufacture of high-performance PMSM for electric vehicles.A fast and accurate magnetic field calculation model for interior permanent magnet synchronous machine(IPMSM)is proposed in this article.Based on the traditional magnetic potential permeance method,the stator cogging effect and complex boundary conditions of the IPMSM can be fully considered in this model,so as to realize the rapid calculation of equivalent magnetomotive force(MMF),air gap permeance,and other key electromagnetic properties.In this article,a 6-pole 36-slot IPMSM is taken as an example to establish its equivalent solution model,thereby the cogging torque is accurately calculated.And the validity of this model is verified by a variety of different magnetic pole structures,pole slot combinations machines,and prototype experiments.In addition,the improvement measure of the machine with different combination of pole arc coefficient is also studied based on this model.Cogging torque and electromagnetic vibration can be effectively weakened.Combined with the finite element model and multi-physics coupling model,the electromagnetic characteristics and vibration performance of this machine are comprehensively compared and analyzed.The analysis results have well verified its effectiveness.It can be extended to other structures or types of PMSM and has very important practical value and research significance.

Fusion Reaction Rate Coefficient for Different Beam and Target Scenarios

Fusion power output is proportional not only to the fuel particle number densities participating in reaction but also to the fusion reaction rate coefficient （or reactivity）, which is dependent on reactant velocity distribution functions. They are usuMly assumed to be dual Maxwellian distribution functions with the same temperature for thermal nuclear fusion circumstances. However, if high power neutral beam injection and minority ion species ICRF plasma heating, or multi-pinched plasma beam head-on collision, in a converging region are required and investigated in future large scale fusion reactors, then the fractions of the injected energetic fast ion tail resulting from ionization or charge exchange will be large enough and their contribution to the non-Maxwellian distribution functions is not negligible, hence to the fusion reaction rate coefficient or calculation of fusion power. In such cases, beam-target, and beam-beam reaction enhancement effect contributions should play very important roles. In this paper, several useful formulae to calculate the fusion reaction rate coefticient for different beam and target combination scenarios are derived in detail

Description of a New Subspecies of the Genus Saurogobio Bleeker (1870)

The genus Saurogobio Bleeker (1870) is a group of small sized cyprinids. Saurogobio dabryi Bleeker (1871) is widely distributed in East Asia.On the basis of careful inspection of morphological and meristic characters of specimen collected from Chenghai Lake in Yunnan and the opening river systems including Pearl River,Minjiang River,Yangtze River,Liaohe River and Songhuajiang River,the Chenghai Lake population of Saurogobio dabryi is considered to represent a new subspecies, Saurogobio dabryi chenghaiensis . Saurogobio dabryi chenghaiensis is distinguished by the combination of following characters.Rostral cap developed,covering over upper lip,and lips with developed papillae.Body and caudal peduncle very slender,body depth 12 7%-15 0% of standard length(SL),caudal peduncle depth 5 5%-6 1% of SL and 31 8%-39 1% of caudal peduncle length.A longitudinal dark stripe present along the axis on each side of body and 6-11 stick shaped black spots (its widths being 25%-50% of its lengths respectively) occur along the stripe.Distance from pelvic fin origin to anus is more than 50% of pelvic fin length.The length of the shortest caudal fin ray is less than 50% that of the longest one.The new subspecies occurs only in Chenghai Lake,Yunnan,China.

Stability analysis of concrete gravity dam on complicated foundation with multiple slide planes

A key problem in gravity dam design is providing enough stability to prevent slide, and the difficulty increases if there are several weak structural planes in the dam foundation. Overload and material weakening were taken into account, and a .finite difference strength reserve method with partial safety factors based on the reliability method was developed and used to study the anti-slide stability of a concrete gravity dam on a complicated foundation with multiple slide planes. Possible slide paths were obtained, and the stability of the foundation with possible failure planes was evaluated through analysis of the stress distribution characteristics. The results reveal the mechanism and process of sliding due to weak structural planes and their deformations, and provide a reference for anti-slide stability analysis of gravity dams in complicated geological conditions.

Laser Surface Textured PTFE Inhibitation for Stick-Slip Phenomenon Under Boundary Lubrication

When the machine tool is in the start-and stop-stages,the stick-slip phenomenon will be observed and highprecision positioning,machining accuracy and fretting feed will not be guaranteed. The most critical reason is that there is the difference between the dynamic and the static friction coefficients. Textures with different area ratios are fabricated on the surfaces of the upper PTFE-based composite and the friction tests are carried out on a reciprocating tribotester under the boundary lubrication and flat-on-flat contact conditions. The results show that there exists an optimal textured area ratio of 19.6% that can minimize the difference between the dynamic and the static friction coefficients.