37 research outputs found
Phase-only array transmit beamforming without iterative/numerical optimization methods
In this letter, we address the problem of phase-only transmit beamforming to generate a wide beam with an almost flat mainlobe for phased arrays. Instead of resorting to time-demanding optimization procedures, the proposed method is grounded on the Fourier analysis and exploits the fact that radiation pattern can be written as the Fourier transform of the aperture illumination function. In this context, we consider a complex linear frequency modulated illumination function and derive the equations allowing for a control of the beam width. The related computational complexity is linear in the number of the array elements. The numerical examples show the effectiveness of the proposed method in forcing the desired beam shape with good sidelobes’ properties and also in comparison with an iterative competitor
A Framework for Life Cycle Cost Estimation of a Product Family at the Early Stage of Product Development
A cost estimation method is required to estimate the life cycle cost of a product family at the early stage of product development in order to evaluate the product family design. There are difficulties with existing cost estimation techniques in estimating the life cycle cost for a product
family at the early stage of product development. This paper proposes a framework that combines a knowledge based system and an activity based costing techniques in estimating the life cycle cost of a product family at the early stage of product development. The inputs of the framework are the product family structure and its sub function. The output of the framework is the life cycle cost of a product
family that consists of all costs at each product family level and the costs of each product life cycle
stage. The proposed framework provides a life cycle cost estimation tool for a product family at the early stage of product development using high level information as its input. The framework makes it possible to estimate the life cycle cost of various product family that use any types of product structure. It provides detailed information related to the activity and resource costs of both parts and
products that can assist the designer in analyzing the cost of the product family design. In addition, it can reduce the required amount of information and time to construct the cost estimation system
Technology 2003: The Fourth National Technology Transfer Conference and Exposition, volume 2
Proceedings from symposia of the Technology 2003 Conference and Exposition, Dec. 7-9, 1993, Anaheim, CA, are presented. Volume 2 features papers on artificial intelligence, CAD&E, computer hardware, computer software, information management, photonics, robotics, test and measurement, video and imaging, and virtual reality/simulation
UAVs for the Environmental Sciences
This book gives an overview of the usage of UAVs in environmental sciences covering technical basics, data acquisition with different sensors, data processing schemes and illustrating various examples of application
Technology 2000, volume 1
The purpose of the conference was to increase awareness of existing NASA developed technologies that are available for immediate use in the development of new products and processes, and to lay the groundwork for the effective utilization of emerging technologies. There were sessions on the following: Computer technology and software engineering; Human factors engineering and life sciences; Information and data management; Material sciences; Manufacturing and fabrication technology; Power, energy, and control systems; Robotics; Sensors and measurement technology; Artificial intelligence; Environmental technology; Optics and communications; and Superconductivity