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In this paper, two sets of experimental results to extract the two effective elastic moduli, the effective shear modulus, and the effective Poisson's ratio for the gerbil cochlear partition are analyzed. In order to accomplish this, a geometrically nonlinear composite orthotropic plate model is employed. The model is used to predict both out-of-plane and in-plane motion of the partition under a static finite area distributed load. This loading condition models the small, but finite size, probe tips used in experiments. Both in-plane and out-of-plane motion are needed for comparison with recent experimental results. It is shown that the spatial decay rate (the space constant) for the in-plane deflection is different than for the out-of-plane deflection, which has a significant effect on the derived partition properties. The size of the probe tip is shown to have little influence on the results. Results are presented for two types of boundary conditions. Orthotropy ratios determined from the experimental data are found to vary with longitudinal position and choice of boundary conditions. Orthotropy ratios (the ratio of the two elastic moduli) are in the range of 65 close to the base to 10 in the upper middle turn of the cochlea.

Material properties of the cochlear partition play an important role in understanding the cochlear hydrodynamics. In this paper, two sets of experimental results are analyzed to extract the orthotropic material properties of the gerbil cochlear partition at different longitudinal locations. In order to accomplish this, a geometrically nonlinear composite orthotropic plate model is employed. The model is used to predict both out-of-plane and in-plane motion of the partition under a static finite area distributed load. Both in-plane and out-of-plane motion are needed for comparison with recent experimental results. It is shown that the spatial decay rate (the space constant) for the in-plane deflection is different from the out-of-plane deflection, which has a significant effect on the derived partition properties. The size of the probe tip is shown to have little influence on the results. Results are presented for two types of boundary conditions. Orthotropy ratios (the ratio of the two elastic moduli) determined from the experimental data are found to vary with longitudinal position and choice of boundary conditions. Orthotropy ratios vary from 65 close to the base to 10 in the upper middle turn of the cochlea.

Compared with other projects, information technology (IT) projects are unique, which are characterized by emergency, uniqueness, one shot, short term and uncertainty. To implement an IT project successfully, problems in the IT project management must be found, analyzed and solved and there must be successful project management and management innovation as well. Then, what are the major problems in IT project management? Who can conduct IT project management successfully? How to conduct IT project management successfully? How to innovate IT project management? This paper discusses all these questions. And on the basis of the above, it also draws the following conclusion: The project managers play a key role in both implementing and controlling stages of IT projects. The project managers should regard IT project management as a system, deal with various relationships with the parties concerned in the system well, and conduct management innovation. By adequate communication channels, the project managers should communicate with all the stakeholders, i.e. the factors in the system, including the client, the management, and the team members to know their requirements, needs and the problems respectively. Only by so doing, can they give satisfactory responsiveness to the client, get support from the management, lead and control the team outstandingly, and make the team work efficiently. While by management innovation, the project managers can make all the factors in their management system interact effectively and efficiently with each other to create a synergy effect. Only by so doing, can the IT project management be successful, and finally, can the IT projects be implemented successfully. Keywords-management innovation; IT project management; IT project managersI.

Knowledge of the residual stress state in wheels resulting from manufacturing and subsequent service loading is useful for several practical reasons. The ability to estimate residual stress levels permits the tuning of manufacturing processes to control the magnitude and distribution of these stresses in new wheels in order to achieve safe performance in service. Similarly, understanding the redistribution of residual stresses following application of service loads (wheel/rail contact and thermal stresses) is crucial to avoid operating conditions which may lead to premature wheel failure.Axisymmetric (2-dimensional) analyses are typically performed in order to conduct manufacturing process simulations since these processes affect the entire wheel in a circumferentially uniform sense.Generally, analyses involving service loading have sought to identify the "shakedown state" at which the residual stress distribution stabilizes after some number of loading cycles. In order to properly account for service loads, 3-dimensional models are required since contact and brake shoe thermal loading are not axisymmetric. Since the as-manufactured residual stress distribution must be considered in a service loading simulation, 3-dimensional modeling of this process is required. This paper presents a preliminary comparison of 2-and 3-dimensional modeling of the wheel heat treatment process. Except for the increased computational time required for the 3-dimensional analysis, the results agree favorably. The 3-dimensional model is used to simulate service loads involving wheel-rail contact loading representative of a typical passenger car. The model is exercised with a variety of material models for comparison with previous work. Results are presented for multiple loading scenarios and shakedown stress states are established for a range of applied loads. INTRODUCTIONResidual stresses are important to understand in order to avoid operating conditions which may lead to development of adverse stresses which can cause premature wheel failure. Residual stresses in wheels originate during the manufacturing process and are subsequently modified when wheels are placed in service and subjected to repeated wheel/rail contact and thermal loading during on-tread friction braking. The manufacturing process generally leaves the wheel rim in a state of residual compression. This compression helps to resist wheel tread crack formation. Thermal loading from ontread friction braking has been demonstrated to cause rim stress reversal from compression to tension, leading to the development of wheel tread thermal cracking.Early attempts to estimate residual stresses in wheels considered a combination analysis. Standard finite element techniques were applied to estimate the residual stresses due to the quenching and annealing portions of the manufacturing process [1,2]. These stresses were then used as an initial condition for subsequent consideration of mechanical (wheel/rail contact) and thermal (from friction braking) stresses that were ana...