Geometrical product specification and verification (GPS) matrix system is a universal tool for expressing geometrical requirements on product design drawings. It benefits product designers through providing detailed description of functional requirements for geometrical products, and through referring to corresponding manufacturing and verification processes. In order to overcome current implem...

This paper presents a prediction of the millimeterwave multipath propagation characteristics in the typical urban environment. To analyze the propagation in an outdoor environment, the three dimensional model based on the geometrical optics and the uniform geometrical theory of diffraction is employed. Prediction by the three dimensional ray tracing method needs a detailed map, which records lo...

Due to increasing the number of decision-making criteria in today's ever complicated geometrical optimization problems, the traditional multiobjective optimization approaches, whether a priori, a posteriori or interactive's, found to be insufficient and ineffective. In this paper the drawbacks of the current algorithms are reviewed and the urgent need for inserting a learning componen...

A novel, digitally based geometrical packing algorithm, called DigiPac, is used in an investigation into the segregation of non-spherical particles, due to vibration or shaking. Comparison between simulations and experiments shows a consistent, albeit qualitative, correlation, supporting the hypothesis that segregation can be explained from a geometrical instead of mechanistic point of view, in...

Screw theory has demonstrated its wide applications in robot kinematics and statics. We aim to propose an intuitive geometrical approach to obtain the reciprocal screws for a given screw system. Compared with the traditional Plücker coordinate method, the new approach is free from algebraic manipulation and can be used to obtain the reciprocal screws just by inspecting the structure of manipula...

Deciding how to teach geometry remains a demanding task with one of major arguments being about how to combine the intuitive and deductive aspects of geometry into an effective teaching design. In order to try to obtain an insight into tackling this issue, this paper reports an analysis of innovative geometry textbooks which were published in the early part of the 20th Century, a time when sign...

A new method of optimization on linear parabolic solar collectors using exergy analysis is presented. A comprehensive mathematical modeling of thermal and optical performance is simulated and geometrical and thermodynamic parameters were assumed as optimization variables. By applying a derived expression for exergy efficiency, exergy losses were generated and the optimum design and operating co...

The purpose of functional tolerancing process is to define the geometrical specifications of parts ensuring functional requirements. For automotive and aircraft industries, the tolerance synthesis has become an important issue in product design process. Indeed, designers need methods and rules to determine the tolerances. To define rules, a mathematical formulation of tolerance synthesis is det...

The Geometrical Product Specification (GPS) is a set of standards widely adopted by modern manufacturing industries for expressing tolerances and communicating geometrical requirements. It has great benefit in reduction of manufacturing cost, alleviation of design and manufacturing misunderstandings and insurance of the consistency of geometric characteristics for the machining products through...

We propose a unified framework for the analysis of estimators of geometrical vector quantities and vector systems through a collection of performance measures. Unlike standard performance indicators, these measures have intuitive geometrical and physical interpretations, are independent of the coordinate reference frame, and are applicable to arbitrary parameterizations of the unknown vector or...