Local motions and deformations of organs between treatment fractions introduce geometrical uncertainties into radiotherapy. These uncertainties are generally taken into account in the treatment planning by enlarging the radiation target by a margin around the clinical target volume. However, a practical method to fully include these uncertainties is still lacking. This paper proposes a model based on the principal component analysis to describe the patient-specific local probability distributions of voxel motions so that the average values and variances of the dose distribution can be calculated and fully used later in inverse treatment planning. As usually only a very limited number of data for new patients is available; in this paper the analysis is extended to use population data. A basic assumption (which is justified retrospectively in this paper) is that general movements and deformations of a specific organ are similar despite variations in the shapes of the organ over the population. A proof of principle of the method for deformations of the prostate and the seminal vesicles is presented.

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In the process of job management, many problems are faced. So that good management is needed, which is required to provide problem solving. Problem solving is done by conducting research on objects, in order to produce quality management. Research is a way to objectively seek truth, where truth here is not only conceptually or deductively obtained, but also must be tested empirically. The purpose of this paper is to provide an understanding of 10 (ten) basic research, as a form of research management, namely the understanding of research, research, research steps, motivation and research objectives, research processes, characteristics of research, preliminary studies, benefits and objectives preliminary studies, how to conduct preliminary studies, concepts of research methods and methodologies.

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