Quad-tree index has been widely used in geo-spatial database management and GIS. Yet, how to determine a suitable index depth of quad-tree for an optimal query in terms of query speed remains a difficult task. Bearing this task in mind, the authors analyze the close correlation between the index depth and the index range. The query efficiency of quad-tree is introduced as a quantitative measure...

In this paper, the algorithm was designed of quad-tree spatial search based on spatial information multi-dimensional features, the traditional quad-tree algorithm has been improved to a specific spatial attribute value binding in the quad-tree leaf nodes, a large number with a specific operation irrelevant attributes are excluded, to the effect of finding targets. This algorithm is applied in t...

We prove that every hyperplane of the symplectic dual polar space DW (5, K) that contains a quad is either classical or the extension of a non-classical ovoid of a quad of DW (5, K).

In this paper, the design of equal-split quad-band Wilkinson power divider is presented. The design consists of two quad-band transmission line transformers and four isolation resistors. Standard transmission line theory and even/odd modes analyses are used to obtain closed form expressions that are solved using particle swarm optimization technique to find the required divider parameters (leng...

The multi-level programming problems are attractive for many researchers because of their application in several areas such as economic, traffic, finance, management, transportation, information technology, engineering and so on. It has been proven that even the general bi-level programming problem is an NP-hard problem, so the multi-level problems are practical and complicated problems therefo...

This paper presents an overview of the most effective ideas for the Quad-rotor project. The concept of modeling using different methods is presented. The modeling part presented the nonlinear model, and the concept of linearization using small disturbance theory. Parameter identifications part explained the most important parameters that affect the system stability and tried to get suitable sol...

There are number of failures are recorded in UAV projects because of its non-linearity nature. In Quad-rotor type Unmanned Aerial Vehicles, position controlling is one of the most critical tasks and suitable Position stabilization controller is the essential part of these types of unmanned systems. In this paper a position stabilization (i.e. x and y axes) control with noise rejection system is...

This research work is done to optimize the search in hierarchal database by using Quad Tree. Quad Tree is a tree which consists of a node having 4 sub child nodes.[1] Quad Tree is used in many fields such as computer graphics to find out a desired pixel in graphics and collision detection in 3-D gaming. There are various other applications of quad tree in different fields like weather forecasti...

We study the equation$\begin{equation*} (-\Delta)^s u = |x|^{\alpha} u^{\frac{N+2s+2\alpha}{N-2s}}\mbox{ in }\mathbb{R}^N, \end{equation*} \quad\quad\quad\quad\quad\quad\text{(P)}$where $ is fractional Laplacian operator with 0 < s 1 $, \alpha>-2s and N>2s $. prove linear non-degeneracy of positive radially symmetric solutions equation (P) and, as a consequence, uniqueness result those...