基于字形动态描述库的Webfont汉字生成方法

现有的Webfont汉字生成方法,需要设计专门的字库,工作量大且灵活性差。针对这一问题,将汉字特征点用字形动态描述库记录,在此基础上提出一种新的Webfont汉字的自动生成方法。研究基于特征点描述的汉字笔画提取、连接和优化方法,并对比基于B样条曲线和贝塞尔曲线的字形优化效果。为方便用户进行个性化字体生成,设计了用户自定义字形优化方法。实验结果证明,基于汉字字形动态描述库,用户无需下载字库,即可以在网页上生成符合自身需求的Webfont汉字。

Research on the closure and creep mechanism of circular tunnels

A numerical code called Rock Failure Process Analysis (RFPA2D) was em- ployed to investigate the closure,damage and failure behavior of the horizontal tunnels.In this code the time-dependent deformation was described in terms of evolution of meso- scopic structure,leading to progressive degradation of elastic modulus and failure strength of material.In terms of material degradation,a series of numerical simulations were per- formed to study the convergence and subsequent failure in circular tunnels.The numerical results provide a complete illumination for the closure,damage and failure behavior with different loading conditions.It is shown that the depth and the ratio of far field stresses play an important role in the creep behavior of tunnels.Creep failure is expected to occur in the direction of the smallest far field stress component,which means that rheological failure of tunnels is influenced not only by the rock characteristic around the tunnels but also by the orientation and distribution of far field stress on a global scale.

Constructions with Numbers

Pascal Triangle is more of a number construction （body） then an array of the binomial coefficients. It is a mathematical body, like the digital code feeds for computer but with 2 dimensions. And there should be bodies with x-dimensions and even abnormal or irregular appearances.

Towards a New Geoid Model of Tanzania Using Precise Gravity Data

The new geoid model of Tanzania is a major breakthrough in the determination of vertical heights for the past 60 years. A new geoid model has been computed using precise gravity data supplemented with marine gravity data from Gravity Recovery and Climate Experiment （GRACE） satellite and new high-resolution satellite gravity data from Gravity field and steady-state Ocean Circulation Explorer （GOCE）. A digital terrain model was also used based on 15＂ Shuttle and Rader Terrain Model （SRTM） data. The use of gravity data makes an orthometric height easily computed using Global Navigation Satellite System （GNSS）. The GNSS is being used in many African countries including Tanzania and soon it will replace conventional leveling technique and avoid frequent maintenance of benchmarks. This paper presents preliminary result of a new geoid model which shows that by using precious gravity data and Remove-Compute-Restore technique, an accuracy of 10 cm can be reached.

Numerical Calculation and Experiment of Coupled Dynamics of the Differential Velocity Vane Pump Driven by the Hybrid Higher-order Fourier Non-circular Gears

The transmission systems of the differential velocity vane pumps （DVVP） have periodic vibrations under loads. And it is not easy to find the reason. In order to optimize the performance of the pump, the authors proposed DVVP driven by the hybrid Higher-order Fourier non-circular gears and tested it. There were also simi- lar periodic vibrations and noises under loads. Taking into account this phenomenon, the paper proposes fluid mechanics and solid mechanics simulation methodology to analyze the coupling dynamics between fluid and transmission system and reveals the reason. The results show that the pump has the reverse drive phenomenon, which is that the blades drive the non-circular gears when the suction and discharge is alternating. The reverse drive phenomenon leads the sign of the shaft torque to be changed in positive and negative way. So the transmis- sion system produces torsional vibrations. In order to confirm the simulation results, micro strains of the input shaft of the pump impeller are measured by the Wheatstone bridge and wireless sensor technology. The relation- ships between strain and torque are obtained by experimental calibration, and then the （rue torque of input shaft is calculated indirectly. The experimental results are consistent to the simulation results. It is proven that the peri- odic vibrations are mainly caused by fluid solid coupling, which leads to periodic torsional vibration of the trans- mission system.

Hybrid memristor-CMOS neurons for in-situ learning in fully hardware memristive spiking neural networks

Spiking neural network,inspired by the human brain,consisting of spiking neurons and plastic synapses,is a promising solution for highly efficient data processing in neuromorphic computing.Recently,memristor-based neurons and synapses are becoming intriguing candidates to build spiking neural networks in hardware,owing to the close resemblance between their device dynamics and the biological counterparts.However,the functionalities of memristor-based neurons are currently very limited,and a hardware demonstration of fully memristor-based spiking neural networks supporting in-situ learning is very challenging.Here,a hybrid spiking neuron combining a memristor with simple digital circuits is designed and implemented in hardware to enhance neuron functions.The hybrid neuron with memristive dynamics not only realizes the basic leaky integrate-and-fire neuron function but also enables the in-situ tuning of the connected synaptic weights.Finally,a fully hardware spiking neural network with the hybrid neurons and memristive synapses is experimentally demonstrated for the first time,and in-situ Hebbian learning is achieved with this network.This work opens up a way towards the implementation of spiking neurons,supporting in-situ learning for future neuromorphic computing systems.