A multiaxis thrust-vectoring nozzle designed to have equal ow-turning capability in pitch and yaw was conceived and experimentally tested for internal static performance at Langley Research Center. The cruciform-shaped, convergent-divergent nozzle turned the ow for thrust vectoring by deeecting the divergent surfaces of the nozzle, called aps. Methods for eliminating physical interference betwe...

We report the discovery of a coherent magnetic spiral structure within the nearby ringed Sab galaxy NGC4736. High sensitivity radio polarimetric data obtained with the VLA at 8.46GHz and 4.86GHz show a distinct ring of total radio emission precisely corresponding to the bright inner pseudoring visible in other wavelengths. However, unlike the total radio emission, the polarized radio emission r...

This paper studies the path planning problem for mobile robots to move smoothly and safely along a shorter curvature-constrained path in completely known dynamic environments. The cost of travel is defined by an obstacle-avoidance cost, which is designed as a weighted penetration depth to vertices of obstacles, and a length cost. The path is composed of a pre-specified number of cubic spiral se...

Aims. We study the magnetic field structure, strength, and energy density in the Scd galaxy M33. Methods. Using the linearly polarized intensity and polarization angle data at 3.6, 6.2 and 20 cm, we determine variations of Faraday rotation and depolarization across M33. We fit a 3-D model of the regular magnetic field to the observed azimuthal distribution of polarization angles. We also analyz...

A m ultiaxis thrust-vectoring nozzle designed to have equal ow-turning capability in pitch and yaw was conceived and experimentally tested for internal static performance at Langley Research Center. The cruciform-shaped, convergent-divergent nozzle turned the ow for thrust vectoring by deeecting the divergent surfaces of the nozzle, called aps. Methods for eliminating physical interference betw...

This paper addresses a new path planning method, whose objective is to build a process to generate a path which connects two configurations of car-like mobile robots. The generated path is constituted by both cubic spirals and straight lines, and has continuous and bounded curvature. We will show the procedure to find the path with theoretical minimal length and to simplify it for the reason of...

Abstract Introduction and aim Aortic annulus dimensions change during the cardiac cycle. A retrospective ECG-gated (Spiral) scan is default technique for pre TAVR evaluation since it includes systolic phases considered optimal aortic assessment. Ultra-fast, Low-Dose High-Pitch (FLASH) offers faster, potentially low radiation contrast dose scans. However, lacks ability to time data acquisition s...

RATIONALE AND OBJECTIVES To develop an optimal scanning protocol for multislice spiral CT perfusion (CTP) imaging to evaluate hemodynamic changes in liver cirrhosis with diethylnitrosamine- (DEN-) induced precancerous lesions. MATERIALS AND METHODS Male Wistar rats were randomly divided into the control group (n = 80) and the precancerous liver cirrhosis group (n = 40). The control group rece...

This paper presents the spiral array model and its associated algorithms for tonal induction, approximation, and segmentation. The spiral array is a geometric model for tonality that clusters perceptually similar tonal entities. The model summarizes music information as interior points inside an array of spirals. Distances in the spiral array space are used to quantify tonal similarity. The pap...

The growth and development of plants is determined by both genetic and environmental factors. In this study, path analysis was employed to investigate the magnitude of developmental variation among six quantitative characters associated with growth in 29 pitch pine (Pinus rigida Mill.) families at Walden Woods, Lincoln, Mass. Seedlings were grown for six months in two environments: sand (poor) ...