Infine Functions, Nonsmooth Alternative Theorems and Vector Optimization Problems

In this paper we introduce a new notion of infine nonsmooth functions and give several characterizations of infineness property. We prove alternative theorems with mixed constraints (i.e., inequality and equality constraints) being described by invex-infine nonsmooth functions. We establish a necessary and sufficient condition for a solution of a vector optimization problem involving mixed constraints to be a properly efficient solution.     

Theoretical and Experimental Driving-Point Impedance Results of Resonance Circuits in a Gunn Waveguide Oscillator

The frequency tuning range of waveguide oscillator and its stability depend sensitively on the dimension of the resonance cap. Therefore the driving-point impedances with the various dimensions of the resonance cap are calculated by using HFSS(High Frequency Simulation System). In this paper the comparisons between theoretical results of the driving-point impedances as a function of frequency and that of experimental results are described. The oscillation frequency range could be predicted by using the theoretical evaluation methods which are proposed. It shows that resonance cap size and disc height have an effect on the frequency tuning characteristics of Gunn oscillator.     

Experimental verification of drop/impact simulation for a cellular phone

Conducting drop tests to investigate impact behavior and identify failure mechanisms of small-size electronic products is generally expensive and time-consuming. Nevertheless, strict drop/impact performance criteria for hand-held electronic products such as cellular phones play a decisive role in the design because they must withstand unexpected shocks. The design of product durability on impact has heavily relied on the designer's intuition and experience. In this study, a reliable drop/impact simulation for a cellular phone is carried out using the explicit code LS-DYNA. Subsequently globallocal experimental verification is accomplished by means of high-speed photography and impact response measurement. Using this methodology, we predict potential damage locations in a cellular phone and compare them with real statistical data. It is envisaged that development of a reliable methodology of drop/impact simulation will provide us with a powerful and efficient vehicle for improvement of the design quality and reduction of the product development cycle.     

Formation process for and strain effect in InAs quantum dots grown on GaAs substrates by using molecular beam epitaxy

Reflection high-energy electron diffraction (RHEED) and atomic force microscopy (AFM) measurements were used to investigate the dependences of the formation process and the strain on the As/In ratio and the substrate temperature of InAs quantum dots (QDs) grown on GaAs substrates by using molecular beam epitaxy. The thickness of the InAs wetting layer and the shape and the size of the InAs QDs were significantly affected by the As/In ratio and the substrate temperature. The strains in the InAs layer and the GaAs substrate were studied by using RHEED patterns. The magnitude in strain of the InAs QDs formed at a low substrate temperature was larger than that in InAs QDs grown at high substrate temperature. The present results can help to improve the understanding of the formation process and the strain effect in InAs QDs.     

Multiple p-adic L-function

An analytic function interpolating the multiple generalized Bernoulli numbers attached to a primitive Dirichlet character X at negative integers in the complex plane is studied. The multiple p-adic L-function is constructed as the p-adic analog of the above function. Finally, the values of the partial derivative of this multiple p-adic L-function at s = 0 are given. Dedicated to the memory of Boris Moiseevich Levitan     

Numerical methods for computations of nonequilibrium hypersonic flow around bodies

In this paper we present numerical methods for computations of nonequilibrium hypersonic flow of air around bodies including chemical reaction effects and present numerical result of the flow over concave corners. We developed implicit finite difference method to overcome numerical difficulties associated with the lack of resolution behind the shock and near the body. Using our method we were able to find details of the flow properties near the shock and body and were able to continue the computation of the flow for a long distance from the corner of the body.