Let us begin with basic terminology and concepts. We call z = x + iy a complex variable. The imaginary unit i should be treated as a symbol that obeys all the usual laws of algebra together with i2 = −1. We call x = Rez the real part of z and y = Imz the imaginary part of z. We can identify z = x+ iy with a point in the xy-plane (known as the z-plane or the complex plane). The complex conjugate...

With the development of satellite mobile communications, large antennas are now widely used. The precise pointing of the antenna's optical axis is essential for many space missions. This paper addresses the challenging problem of high-precision autonomous pointing control of a large satellite antenna. The pointing dynamics are firstly proposed. The proportional-derivative feedback and structura...

Increasingly, the advent of multislice CT scanners, volume CT scanners, and total body spiral acquisition modes has led to the use of Multi Planar Reconstruction and 3D datasets. In considering 3D resolution properties of a CT system it is important to note that both the in-plane (x,y) and z-axis (slice thickness) influence the visual-ization and detection of objects within the scanned volume. ...

Introduction: Integration of single photon emission computed tomography (SPECT) and computed tomography (CT) scanners into SPECT/CT hybrid systems permit detection of coronary artery disease in myocardial perfusion imaging (MPI). Misregistration between CT and emission data can produce some errors in uptake value of SPECT images. The aim of this study was evaluate the influence...

In these indirect-drive experiments, up to 40 of the 60 OMEGA laser beams enter the hohlraum laser entrance holes (LEHs). The beams are arranged in 3 cones, with entrance angles (i.e., half-cone angles) of 21.42°, 42.02°, and 58.85° for Cones 1, 2, and 3, respectively. The pointing of the cones was adjusted in a series of 3 experimental scans to assess the effects of the beam pointing on the ca...

We describe the muon track direction (pointing backwards along the trajectory) by the zenith angle Θ and azimuth Φ. The position of one point on the muon trajectory can be taken as the point of closest approach to the axis of the detector cylinder. The distance of closest approach of the muon track to the axis is denoted by b in what follows. Uncertainty in the extrapolated track arising from p...

BACKGROUND AND PURPOSE PCT has emerged as an alternative to MR imaging for the assessment of patients with suspected acute stroke. However, 1 disadvantage of PCT is its limited anatomic coverage, which may impact the characterization of hemispheric ischemic strokes. The purpose of this study was to determine the optimal brain CT coverage required to accurately estimate the size of the infarct c...

Given the relationship between spherical aberrations and accommodation, study of these can be helpful to understand accommodative response in subjects with dysfunctions. The purpose this was evaluate on-axis off-axis changes primary secondary aberrations, Z(4,0) Z(6,0), accommodation insufficiency (AI). Ten AI eleven without any dysfunction (control) participated study. On-axis defocus Z(2,0), ...