The production of jets is studied in collisions of virtual photons, specifically for applications at HERA. Photon flux factors are convoluted with matrix elements involving either direct or resolved photons and, for the latter, with parton distributions of the photon. Special emphasis is put on the range of uncertainty in the modeling of the resolved component. The resulting model is compared w...

We will present a new concept of analysis by using visualization of large quantities of simulation data. The time development of 3D object with high temporal resolution provides the opportunity of scientific discovery. We visualize large quantities of simulation data using visualization application 'Virtual Aurora' based on AVS and the parallel distributed processing at “Space Weather Cloud” in...

We present a fast, robust and automatic method for computing centerline paths through tubular structures for application to virtual endoscopy. The key idea is to utilize a skeletonization algorithm which exploits properties of the average outward flux of the gradient vector field of a Euclidean distance function from the boundary of the structure. The algorithm is modified to yield a collection...

In this paper, direct power control (DPC) of three-phase pulsewidth-modulated rectifiers without line voltage sensors is presented. The new system is based on virtual flux (VF) estimation. Theoretical principles of this method are discussed. The steady-state and dynamic behavior of VF-DPC are presented that illustrate the operation and performance of the proposed system compared to a convention...

We point out that in processes involving the parton content of the photon the usual effective photon approximation should be modified. The reason is that the parton content of virtual photons is logarithmically suppressed compared to real photons. We describe this suppression using several simple, physically motivated ansätze. Although the parton content of the electron in general no longer fac...

Background: Virtual education refers to a variety of teaching-learning methods that are implemented and supported electronically. The present study was conducted to determine the effects of group blogging on the attitude of nursing students towards virtual education.    Methods: This was a quasi-experimental pretest-posttest study in which all fifth-semester nursing students (n=25) w...

Due to the frequent drought periods, water consumption increase, and competition of different water-using sectors, the Hirmand catchment is in a critical water status in the Sistan region. This threat has been intensified in recent years. To cope with this problem, we must pay more attention to different types of water use such as virtual water as a water saving method. The present study calcul...