1. Introduction.

  title={1. Introduction.},
  author={Zhi Chen},
  journal={Journal of the ICRU},
  volume={13 1-2},
  • Zhi Chen
  • Published 31 December 1971
  • Political Science
  • Journal of the ICRU
The first non-racial elections in South Africa, held on 27/04/1994, ushered in a government whose political framework is grounded on principles of democracy, nonracism and non-sexism. The ‘rainbow people of the South’ is a phrase popularized by Archbishop Desmond Tutu to describe the new post-apartheid South African society. The ‘rainbow’ metaphor captures both the different backgrounds of South Africans and the common non-racial values to which the nation should strive. Underlying both this… 

Figures from this paper


A Theory for Multiresolution Signal Decomposition: The Wavelet Representation
  • S. Mallat
  • Computer Science
    IEEE Trans. Pattern Anal. Mach. Intell.
  • 1989
It is shown that the difference of information between the approximation of a signal at the resolutions 2/sup j+1/ and 2/Sup j/ can be extracted by decomposing this signal on a wavelet orthonormal basis of L/sup 2/(R/sup n/), the vector space of measurable, square-integrable n-dimensional functions.
Broadband Planar Antennas: Design and Applications
Foreword. Preface. Acknowledgements. 1 Planar Radiators. 1.1 Introduction. 1.2 Bandwidth Definitions. 1.2.1 Impedance Bandwidth. 1.2.2 Pattern Bandwidth. 1.2.3 Polarization or Axial-ratio Bandwidth.
Structured importance sampling of environment maps
This work introduces structured importance sampling, a new technique for efficiently rendering scenes illuminated by distant natural illumination given in an environment map, and presents a novel hierarchical stratification algorithm that uses the authors' metric to automatically stratify the environment map into regular strata.
All-frequency shadows using non-linear wavelet lighting approximation
This work presents a method, based on pre-computed light transport, for real-time rendering of objects under all-frequency, time-varying illumination represented as a high-resolution environment map, using non-linear wavelets for accurate rendering.
Generalized wavelet product integral for rendering dynamic glossy objects
This paper presents an efficient sub-linear algorithm to render dynamic glossy objects under time-variant all-frequency lighting and arbitrary view conditions in a few seconds on a commodity CPU, orders of magnitude faster than previous techniques.
Triple product wavelet integrals for all-frequency relighting
This paper proposes a new mathematical and computational analysis of pre-computed light transport, and gives efficient linear and sublinear-time algorithms for Haar wavelets, incorporating non-linear wavelet approximation of lighting and BRDFs.
Wavelet importance sampling: efficiently evaluating products of complex functions
A novel hierarchical sample warping algorithm is presented that generates high-quality point distributions, which match the wavelet representation exactly and is more than an order of magnitude more efficient than the best previous techniques.
Bidirectional importance sampling for direct illumination
The notion of bidirectional importance sampling is introduced, in which samples are drawn from the product distribution of both the surface reflectance and the light source energy, which achieves significant quality improvements over previous sampling strategies for the same compute time.
The rendering equation
An integral equation is presented which generalizes a variety of known rendering algorithms and a new form of variance reduction, called Hierarchical sampling, which may be an efficient new technique for a wide variety of monte carlo procedures.
Efficient Multidimensional Sampling
Based on a generalized concept of stratification, an efficient sampling scheme that consistently outperforms previous techniques is presented by assembling sampling patterns that are stratified in the sense of jittered sampling and N‐rooks sampling at the same time.