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Image denoising is a challenging work in outdoor image applications. Edges get blurred while noises get filtered. A novel edge-preserving filtering method was proposed in this paper. A gradient based inhomogeneous mean matrix was presented to prevent the edges from smoothing. And its sparse structure was constructed to reduce the computational cost. The effectiveness and robustness of our algorithm...
Haze removal is a challenging work in outdoor image applications. Physical model based restoration methods are accepted with higher pertinence, while non-physical model based enhancement methods are more robust and widely applied. A novel haze removal algorithm based on tensor weighted least square decomposition was presented in this paper. By either progressively or recursively applying this decomposition,...
One of the objectives of METIS-II project is to facilitate discussion on scenarios, use cases, KPIs and requirements for 5G, building upon the comprehensive work conducted in the METIS-I project and taking the work of other European projects as well as other bodies such as ITU-R, NGMN, etc. into account. This paper analyses the landscape of 5G use cases and presents METIS-II 5G use cases that cover...
In this paper, we study the energy efficiency of multicast service in interference-limited heterogeneous networks (HetNets). We propose a new power model for base stations (BSs) where the impact of system load, antenna port, carrier number, as well as the power supply and cooling system, is together taken into consideration. Furthermore, we define network energy efficiency for multicast service as...
In this paper, we study and optimize the energy efficiency performance of heterogeneous network (HetNet) with the help of self-organized network (SON). Firstly, we propose a new and general power model for different types of base stations (BSs), where the impact of system load (including power load and bandwidth load), antenna port, carrier number, as well as the power supply and cooling system, is...
The base station (BS) density configuration is a key factor to improve energy efficiency (EE) performances. In this paper, BS density configurations for achieving the optimal EE performance in two-tier cellular networks are analyzed, where the Poisson point process (PPP) is used to model the BS spatial distribution. To make the EE performances trackable and analyzable, the BS density optimization...
In this paper, we focus on the hopping pattern design for device-to-device (D2D) discovery. The requirements of hopping pattern is discussed, where the impact of specific system constraints, e.g., frequency hopping, is also taken into consideration. Specifically speaking, we discover and utilize the novel feature of resource hopping, i.e., "hopping invariant" to design four new hopping patterns...
Characterizing user access methods in heterogeneous cloud radio access networks (H-CRANs)is critical for performance optimization. Different from the user access in cloud radio access networks, the inter-tier interference from macro base station has a great impact on user access in H-CRANs. In this paper, after considering the inter-tier interference, the ergodic rates of downlink H- CRANs for two...
In this paper, we investigate the location optimization for opportunistic cooperative networks under Rayleigh fading channels. We study both decode-and-forward (DF) and amplify-and-forward (AF) and derive the closed-form solution for the optimal location. It is interesting to find that the optimal relay location is identical for either DF or AF, and it is related to the power configuration of nodes...
A numerical method for solving nonlinear Fredholm integral equations of second kind is proposed. The Fredholm type equations which have many applications in mathematical physics are then considered. The method is based upon hybrid function approximate. The properties of hybrid of block-pulse functions and Taylor series are presented and are utilized to reduce the computation of nonlinear Fredholm...
A numerical method to solve Lane-Emden equations as singular initial value problems is presented in this work. This method is based on the replacement of unknown functions through a truncated series of Chebyshev expansions of function. The collocation method transforms the differential equation into a system of algebraic equations. It also has application in a wide area of differential equations....
A numerical solution to solve Fredholm integral equation is presented in this work. The method is based on the replacement of unknown functions through Bernstein polynomials. The collocation method transforms the Fredholm equations into a system of algebraic equations. Also, convergence and rate of convergence are given. The procedure has great potential to be implemented in more complex systems where...
In this paper, we investigate the outage performance of decode-and-forward (DF) based opportunistic cooperative communications with channel estimation errors at the receivers under Rayleigh fading channels, in which the effect of the direct link has been explicitly evaluated. To be specific, the exact expression of outage probability has been derived for arbitrary values of signal-to-noise ratio (SNR)...
In the planning of cellular networks, link budget calculation is the first step to get the maximum allowable cell radius that guarantees a target signal to interference plus noise ratio (SINR) with a certain level of outage probability at the cell border. The interference margin as one of key inputs for link budget is used to compensate for co-channel interference. In this paper, a mathematical analysis...
In this paper, we investigate the location optimization for decode-and-forward (DF) opportunistic cooperative networks, in which the impact of the availability of the direct link between the source and the destination has been studied. Under Rayleigh fading channels, the closed-form solution for the optimal location is derived. It is interesting to find that the optimal relay location is related to...
In this paper, we investigate resource allocation for decode-and-forward (DF) opportunistic cooperative networks, where the availability of the direct link between the source and the destination has been taken into consideration. In addition to separate power allocation and location optimization, we also consider joint resource allocation to minimize the outage probability. Under Rayleigh fading channels,...
A simulation research concerning the gap flow performance of multi-pad hydrostatic thrust bearing having circular cavities in the large-scale vertical CNC lathe was described. The Finite Volume Method of Fluent has been used to compute fluid three-dimensional velocity field and pressure field of gap flow between the revolution working table and bearing pad. This study theoretically analyzes the influence...
This paper investigates a simple and effective power allocation method to maximize the Effective Configuration Duration (ECD) in wireless sensor networks, which aims to minimize the signaling overhead needed to perform relay nodes selection, Cooperative Set update and power allocation, resulting in obvious power saving and lifetime extension. Compared with traditional allocation schemes, this method...
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