关于赛珍珠研究的几个有待深入的问题

赛珍珠研究还有几个有待深入的问题:1 关于赛珍珠可不可以写入20世纪中国文学史的问题,可以从作家对自我身份的认定以及从作品的性质来决定。赛珍珠多次说自己"也是一个中国人",而她的作品大部分跟中国20世纪30年代的"乡土文学"有着紧密的血缘关系,因此她可以写入中国文学史。2 如何评价当年的西方传教活动及赛珍珠的传教士身份,总体上说,西方的传教活动对开启民智、加速中华民族的现代文明进程起到了一定的推动作用。赛珍珠是一位真诚善良、热心为中国人民服务的人。3 怎样评价赛珍珠的贡献,要看到她的"人桥"作用的特点本意在中美双方的"沟通"上,但重在对双方文化的匡正和建设上。4 要加强有关资料的搜集与整理。

Vibration control of pedestrian-bridge vertical dynamic coupling interaction based on biodynamic model

The human-induced vertical vibration serviceability of low-frequency and lightweight footbridges is studied based on the moving mass-spring-damper（MMSD） biodynamic model, and the mass damper（TMD） with different optimal model parameters being used to control the vertical vibration.First, the MMSD biodynamic model is employed to simulate the pedestrians, and the time-varying control equations of the vertical dynamic coupling system of the pedestrian-bridgeTMD are established with the consideration of pedestrianbridge dynamic interaction; and the equations are solved by using the Runge-Kutta-Felhberg integral method with variable step size. Secondly, the footbridge dynamic response is calculated under the model of pedestrian-structure dynamic interaction and the model of moving load when the pedestrian pace frequency is consistent with the natural frequency of footbridge. Finally, a comparative study and analysis are made on the control effects of the vertical dynamic coupling system in different optimal models of the TMD. The calculation results show that the pedestrian-bridge dynamic interaction cannot be ignored when the vertical human-induced vibration serviceability of low-frequency and light-weight footbridge is evaluated. The TMD can effectively reduce the vibration under the resonance of pedestrian-bridge, and TMD parameters are recommended for the determination by the Warburton optimization model.

Applications of Glass and Glass Fiber Retrofit Polymer in Modern Footbridges

The architecture of footbridge design takes the form of a number of submissions from leading architects and engineers, each setting out their views on bridge design--present and future. It looks at the functions of a bridge, defining purpose of place and context, the spirit of creativity and the reasoned progression of an idea. It also explores the exploitation of materials technology and construction innovation and the tension between lightness and mass and between sculpture and scale. Present parameters of tempered and laminated glass create possibility of modern architecture of footbridges which are being full of transparency and light reflex effects. Four projects, using glass panels designed by Santiago Calatrava, have been presented in this paper. GFRP （glass fiber retrofit polymer） makes new horizon in material technology, helps to enrich new conception of structure with longer durability, low weight of deck and new creation of architecture line. The paper has described a few results of FEM （finite element method） analysis of footbridge with modular bridge GFRP deck system. The footbridge was excited by impact and human-induced vibrations. Composite material consists of glass fibers and polymer matrix is a promising alternative against traditional materials. New architecture and modern material engineering are looking for fresh possibilities of form and shape of structure, long durability and extraordinary technical parameters of building elements.

The Gap and Bridge between the Cultivation of Excellent Engineer and the Need of Enterprises

Industrial demand is the leading core of engineering education reform. Promoting the integration between engineering personnel training and business needs is an important and urgent issue of our outstanding program implementation. Based on the empirical research conclusions of ＂investigation on innovative engineering talent structure of Chinese enterprises＂ and ＂survey of the current outstanding engineer training model＂, analyzing the gap between outstanding engineer training and business needs, proposing to strengthen benefits on personnel training of both schools and enterprises, taking personnel training environment, talent development goals and talent evaluation criteria as a starting point, and promoting personnel training process is deeply involved in the smooth implementation of Outstanding Program.

Damage Identification in Footbridges from Natural Frequency Measurements

The present study aims to develop a robust structural damage identification method that can be used for the evaluation of bridge structures. An approach for the structural damage identification based on the measurement of natural frequencies is presented. The structural damage model is assumed to be associated with a reduction of a contribution to the element stiffness matrix equivalent to a scalar reduction of the material modulus. A computational procedure for the direct iteration technique based on the non-linear perturbation theory is proposed to identify structural damage. The presented damage identification technique is applied to the footbridge over the Slunjcica River near Slunj to demonstrate the effectiveness of the proposed approach. Using a limited number of measured natural frequencies, reduction in the stiffness of up to 100% at multiple sites is detected. The results indicate that the proposed approach can be successful in not only predicting the location of damage but also in determining the extent of structural damage.

Dynamic Characteristic of the Medium Span Concrete Footbridges

Concrete footbridges, due to their mass, stiffness and damping, are perceived as strucaires more resistant to vibration caused by dynamic action of the users. In order to verify the dynamic behaviour of concrete footbridges, a series of field tests and numerical analyses have been carried out. In the paper, the results of the dynamic field tests of three medium span concrete footbridges with different structural systems （frame, beam and arch footbridges） and their dynamic characteristics （mass, stiffness and damping） are presented. The field tests were carried out for different types of vibration excitation caused by walking, running and jumping persons. Furthermore, the vibrational comfort criteria for footbridges are shortly described and verified for examined structures. The study were supplemented by numerical calculation of natural mode shapes and frequencies of the structures using the 3D FEA （finite element analysis） models with elastic supports elements in order to ensure the compatibility of the calculated and measured mode shapes of the footbridges.

Prediction of bridge temperature field and its effect on behavior of bridge deflection based on ANN method

In recent years, the bridge safety monitoring has been paid more attention in engineering field. How- ever, the financial and material resources as well as human resources were costly for the traditional monitoring means. Besides, the traditional means of monitoring were low in accuracy. From an engineering example, based on neural network method and historical data of the bridge monitoring to construct the BP neural network model with dual hidden layer strueture, the bridge temperature field and its effect on the behavior of bridge deflection are forecasted. The fact indicates that the predicted biggest error is 3.06% of the bridge temperature field and the bridge deflection behavior under temperature field affected is 2. 17% by the method of the BP neural net-work, which fully meet the precision requirements of the construction with practical value.