Search results for "Data rate"
showing 10 items of 46 documents
Performance Enhancement of Multimedia Broadcast Multicast Service (MBMS) with Receive Diversity
2007
The aim of this paper is to evaluate the effect of receive diversity on multimedia broadcast multicast service (MBMS) performance in wideband code division multiple access (WCDMA) networks. In addition to time diversity provided by long interleaving and receive diversity provided by multiple receive antennas, 3GPP release 6 specifications for MBMS introduce two macro diversity schemes: soft and selective combining. Diversity techniques are introduced in order to improve the MBMS performance. Improvements help especially the cell edge MBMS users who suffer most from the fading channel conditions. As receive diversity is one of the most efficient diversity techniques this paper examines the s…
Effects of Masking on Open-Circuit Voltage and Fill Factor in Solar Cells
2019
Guidelines for the correct measurement protocol of novel photovoltaic technologies such as perovskites are becoming more frequent in literature. This because, as will be confirmed in this perspective, it is not straightforward to correctly measure the efficiency parameters of these and many other novel solar cells. This is particularly the case for small area research devices which are prone to overestimate the short circuit current density, due to edge effects of various types. To reduce the inaccuracy of current density determination, the common recommended practice is to utilize masks with well‐defined apertures, often smaller than the device active area. Herein we show both experimental…
A penalty-based edge assembly memetic algorithm for the vehicle routing problem with time windows
2010
In this paper, we present an effective memetic algorithm for the vehicle routing problem with time windows (VRPTW). The paper builds upon an existing edge assembly crossover (EAX) developed for the capacitated VRP. The adjustments of the EAX operator and the introduction of a novel penalty function to eliminate violations of the time window constraint as well as the capacity constraint from offspring solutions generated by the EAX operator have proven essential to the heuristic's performance. Experimental results on Solomon's and Gehring and Homberger benchmarks demonstrate that our algorithm outperforms previous approaches and is able to improve 184 best-known solutions out of 356 instance…
Alzheimer: A Decade of Drug Design. Why Molecular Topology can be an Extra Edge?
2017
Background The last decade was characterized by a growing awareness about the severity of dementia in the field of age-related and no age-related diseases and about the importance to invest resources in the research of new, effective treatments. Among the dementias, Alzheimer's plays a substantial role because of its extremely high incidence and fatality. Several pharmacological strategies have been tried but still now, Alzheimer keeps being an untreatable disease. In literature, the number of QSAR related drug design attempts about new treatments for Alzheimer is huge, but only few results can be considered noteworthy. Providing a detailed analysis of the actual situation and reporting the…
HF Noise Measurements Based on Software Defined Radio Dual Receiver and Two Orthogonal Inverted Vee Antennas
2020
Increasing the data transfer rate in the High Frequency (HF) range involves enlarging the bandwidth of the channel from the standard value of 3 kHz to values of 6, 12, 24, 48 and even 96 kHz. Real-time evaluation of the noise power in the channel under such conditions is essential. This paper aims to implement an automated system for real-time measurement of noise in the HF range. It is composed of two Software Defined Radio (SDR) synchronized receivers and two orthogonal Inverted Vee antennas. Testing the system demonstrates its ability to distinguish between noise and signals generated as a result of human activity. Preliminary results of measurements performed in an urban location are co…
Autonomous Mooring towards Autonomous Maritime Navigation and Offshore Operations
2020
Bollard is a vital component of mooring system. It is the anchor point for mooring ropes to be fixed in order to secure the vessel or ship. An algorithm that translates the segmented mask of bollard output from masked R-CNN along with bounding box and associated class probability to its corresponding edge coordinate and finally to the single reference point for efficient detection and classification of bollard towards autonomous mooring is presented. At first stage, Mask R-CNN framework is trained with custom built bollard. The model obtained from the training is inferred with real data resulting in instance segment of bollard. The segmented mask obtained contains relatively large amount of…
A fast PC-interface for synchronized sampling of digital data
1994
We describe a high-speed interface unit for a PC-like microcomputer used for pulsar observations at the Northern Cross radiotelescope. The unit allows sampling synchronized to a master UTC clock and asynchronous output to a storage device with a peak data rate of about 2.5 MB/sec.
Reducing the peak and average power for OFDM systems using QAM by constellation shaping
2009
In this paper, we present a shell mapping scheme to reduce the peak and average power of orthogonal frequency division multiplexing (OFDM) signals using quadrature amplitude modulation (QAM) by constellation shaping. Our approach can be considered as an extension of the shell mapping technique introduced originally in the V.34 recommendation of ITU-T. The shell mapping method uses multiple cost functions, each having the OFDM block length N as a parameter. The cost functions are presented in closed form for any N. The main advantage of the proposed scheme is that the peak and average power can be reduced without sacrificing the data rate, and no side information is needed at the receive sid…
Joint Topology and Radio Resource Optimization for Device-to-Device Based Mobile Social Networks
2018
In this paper, we consider a joint topology and radio resource optimization for device-to-device (D2D) based mobile social networks. The considered social network is an interest based which is modeled as a d -intersection binomial random graph. The Radio network is also modeled as a random graph where an edge between any two distinct nodes is activated with a certain probability that is equivalent to the probability of exceeding a certain signal to interference ratio for that link. The entire network is then modeled as an intersection graph between the social and radio induced graphs. Thereafter, network topology is optimized such that enabled social edges satisfy certain network connectivi…
Endpoint Admission Control with Delay Variation Measurements for QoS in IP Networks.
2002
In this paper we describe a novel Endpoint Admission Control scheme (EAC) for IP telephony. EAC mechanisms are driven by independent measurements taken by the edge nodes on a flow of packets injected in the network to probe the source to destination path. Our scheme is characterized by two fundamental features. First, it does not rely on any additional procedure in internal network routers other than the capability to apply different service priorities to probing and data packets. Second, the connection admission decision is based on the analysis of the probing flow delay variation statistics. Simulation results, which focus on a IP telephony scenario, show that, despite the lack of core ro…