نتایج جستجو برای: scatter system

تعداد نتایج: 2240877  

Journal: :Journal of medical imaging 2015
Janelle A Cross Ben McHenry Taly Gilat Schmidt

Biplane fluoroscopy is used for dynamic in vivo three-dimensional motion analysis of various joints of the body. Cross-scatter between the two fluoroscopy systems may limit tracking accuracy. This study measured the magnitude and effects of cross-scatter in biplane fluoroscopic images. Four cylindrical phantoms of 4-, 6-, 8-, and 10-in. diameter were imaged at varying kVp levels to determine th...

Journal: :iranian journal of nuclear medicine 2012
pablo aguiar charalampos tsoumpas albert cot javier pavía domènec ros

introduction: the key characteristics of positron emission tomography (pet) are its quantitative capability and its sensitivity, which allow the in vivo imaging of biochemical interactions with small amounts of tracer concentrations. therefore, accurate quantification is important. however, it can be sensitive to several physical factors. the aim of this investigation is the assessment of the e...

2012
Mohammed Salah Ibrahim Ahmed T. Sadiq Ali M. Sagheer

In this paper scatter search algorithm has been hybridized with simulated annealing algorithm. Scatter search algorithm has some disadvantages which will be solved by using concepts of simulated annealing algorithm. Simulated annealing algorithm will provide scatter search algorithm with more of exploration for problem search space, this will increase ratio of getting optimal solutions. The hyb...

Journal: :Medical physics 2006
Geneviève Jarry Sean A Graham Douglas J Moseley David J Jaffray Jeffrey H Siewerdsen Frank Verhaegen

Kilovoltage (kV) cone beam computed tomography (CBCT) images suffer from a substantial scatter contribution. In this study, Monte Carlo (MC) simulations are used to evaluate the scattered radiation present in projection images. These predicted scatter distributions are also used as a scatter correction technique. Images were acquired using a kV CBCT bench top system. The EGSnrc MC code was used...

2011
Marsil de Athayde Carlos Eduardo Klein Leandro dos Santos Coelho

The environmental/economic dispatch (EED) problem is a large-scale highly constrained nonlinear multiobjective optimization problem. In recent years, this option has received much attention. Many approaches and methods have been reported to solve the multiobjective EED problem in the literature, such as genetic algorithms, artificial neural networks, particle swarm optimization, and differentia...

2005
Jung-Kyun Bong Jong Doo Lee

Purpose: Abutted scatter energy windows used for a triple energy window (TEW) method may provide wrong estimation of scatter. This study is to propose an extended TEW (ETEW) method, which doesn't require abutted scatter energy windows and overcomes the shortcomings of TEW method. Materials & Methods: The ETEW is a modification of the TEW which corrects for scatter by using abutted scatter rejec...

2007
Lada A. Adamic Suresh K. Bhavnani Xiaolin Shi

Information on any given topic is often scattered across the Web. Previously this scatter has been characterized through the inequality of distribution of facts (i.e. pieces of information) across webpages. Such an approach conceals how specific facts (e.g. rare facts) occur in specific types of pages (e.g. fact-rich pages). To reveal such regularities, we construct bipartite networks, consisti...

2005
Suresh K. Bhavnani Frederick A. Peck

Despite the development of extensive websites with high-quality information, and the use of powerful search engines, many users find it difficult to find comprehensive information. One reason for this difficulty is that information, even for narrowly well-defined topics, is highly scattered across websites with no page or site containing all the relevant information. This high scatter can be ex...

2014
Lin Shao Michael Behrisch Tobias Schreck Ivan Sipiran Bum Chul Kwon Daniel Keim

Scatter plots are effective diagrams to visualize distributions, clusters and correlations in two-dimensional data space. For highdimensional data, scatter plot matrices can be formed to show all two-dimensional combinations of dimensions. Several previous approaches for exploration of large scatter plot spaces have focused on ranking and sorting scatter plot matrices based on global patterns. ...

Journal: :Visual neuroscience 1999
P A Hetherington N V Swindale

The receptive-field positions and orientation preferences of neurons occupying the same tangential location in visual cortex are thought to be similar but to have an associated random scatter. However, previous estimates of this scatter may have been inflated by the use of subjective plotting methods, sequential recording of single units, and residual eye movements. Here we report measurements ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید