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Capacity estimation of lithium-ion batteries is significant to achieving the effective establishment of the prognostics and health management (PHM) system of lithium-ion batteries. A capacity estimation model based on the variable activation function-long short-term memory (VAF-LSTM) algorithm is proposed to achieve the high-precision lithium-ion battery capacity estimation. By re-selecting each activation function, the proposed algorithm avoids the low estimation accuracy caused by the fixed activation function of the long short-term memory (LSTM) algorithm, and meanwhile, it can effectively speed up the convergence. The algorithm inputs consider two correlation coefficients so that the health factor with the highest correlation coefficient is chosen as the network input. The experimental data used for the experimental validation is the NASA public battery data under different temperature operating conditions. The validation results show that the estimation accuracy of the VAF-LSTM algorithm under different training sets is greatly improved compared with the traditional LSTM algorithm and the back propagation (BP) algorithm, and the average estimation accuracy can reach more than 97.5%. The improvement of estimation accuracy is also clearly demonstrated under the MAE, MSE, and RMSE. Therefore, the capacity estimation model will provide an important reference role in high-precision battery management systems. [ABSTRACT FROM AUTHOR]

Smart roads, AV and CAV are emerging technologies that represent the new paradigm of mobility. To support the public and private road operators better prepare themselves to implement these technologies in their respective existing or planned infrastructures, there is an urgent need to develop an integrated analysis framework to evaluate the impact of these novel systems on road capacity and safety in function of different market penetration levels of AVs and CAVs. The research focuses on novel smart road geometric design and review criteria based on the performance of AVs and CAVs. The case study of one of the first planned smart roads in Italy has been analysed. [ABSTRACT FROM AUTHOR]

Performance-based seismic engineering has brought new dimensions to tall building design, leading to a major transformation from the prescriptive linear strength-based approach to the explicit non- prescriptive nonlinear deformation-based design approach. Current tall building seismic design practice is based on a well-established design methodology, which starts with a preliminary design followed by two performance evaluation stages. However the designer has no reliable analysis tools at preliminary design stage other than linear response analysis and application of capacity design principles, which in fact may not insure for an acceptable nonlinear response in performance evaluation stage under maximum considered earthquake. In order to fill the gap an attempt is made to develop simple capacity and ductility demand estimation tools for coupled core wall systems to be implemented during the preliminary design stage. [ABSTRACT FROM AUTHOR]

Video broadcast operators target a variety of receiving devices of different resolutions and processing capabilities. In such a heterogeneous TV network, the transport resource consumption is likely to increase. In this paper we estimate the required transport capacity for a broadcast TV network taking into account parameters as currently proposed in standardization bodies. We target constant video quality, hence the TV channel has variable bit rate (VBR). We consider a multicast-based transport system where only the required versions of a TV channel are transported; this leads to fluctuation of the consumed transport capacity over time. The main focus in this paper is on the comparison of a simulcast and a scalable video coding (SVC) transport scheme in several realistic examples with different encoding modes, including spatial and/or quality scalability. To estimate the required transport capacity for simulcast and SVC, we use a comprehensive toolkit based on a Gaussian approximation of the capacity demand. In order to obtain realistic input values for our calculation tools, we characterize the fluctuations of the bit rate associated with a TV channel by encoding a representative set of video clips. Based on the considered realistic examples, we explore under what conditions either the simulcast or the SVC transport scheme is more efficient. [ABSTRACT FROM AUTHOR]

In this paper we consider the theoretical characterization of the ionospheric transmission. More accurately, we derive a closed form expression of the average capacity for Mid-latitude High Frequency (HF) ionospheric channels. Heretofore, this problem has been studied for Rayleigh channels when each tap of the impulse response has a Rayleigh distribution without characterizing the variance of this distribution. In this paper, we extend these works to HF ionospheric channels by evaluating the variance of the amplitude attenuation versus the Doppler spread and then the channel capacity. For a multipath HF ionospheric channel, we model the Doppler phenomenon as a Gaussian profile which is suggested for HF environments. Finally, we derive a closed form expression of the average channel capacity using the probability density function (pdf) of the instantaneous impulse response. Numerical results on both simulated and real measured data are derived at the end of the paper. [ABSTRACT FROM AUTHOR]

Video broadcast operators target a variety of receiving devices of different resolutions and processing capabilities. In such a heterogeneous TV network, the transport resource consumption is likely to increase. In this paper we estimate the required capacity for a broadcast TV network taking into account parameters as currently proposed in standardization bodies. We target constant video quality, hence the TV channel has variable bit rate (VBR). We consider a multicast-based transport system where only the required versions of a TV channel are transported. This leads to fluctuation of the consumed transport capacity over time. In order to characterize the fluctuations of the bit rate associated with one channel, we encoded a representative set of video clips. We compare a simulcast and a scalable video coding (SVC) transport scheme in several realistic examples with different encoding modes. We explore under what conditions one or the other transport scheme is more efficient. [ABSTRACT FROM AUTHOR]

Due to the implementation of an Adaptive Modulation-Coding (AMC) mechanism in the 802.16e physical layer, each connection's bandwidth requirements cannot be statically computed, but they derive as a function of the terminals' instantaneous Signal-to-Noise Ratio (SNR). Therefore, the Connection Admission Control (CAC) mechanism fails to establish an efficient policy that would optimally exploit the system's resources. In this respect, the present paper formulates initially an adequate method for statistically calculating the average capacity of a Mobile-WiMAX system, according to the distribution of the several attenuation factors that affect the signal along the propagation path. In parallel, based on the processing of the terminal's SNR samples, a sophisticated algorithm for filtering out any misleading measurements is developed. This second method aims at predicting the upcoming Modulation-Coding state of every connection, so as to acquire a short-term view of its spectrum demands. Finally, all the above info collected from both the estimation methods is utilized by the CAC procedure in order to perform an as accurate as possible computation of the resource availability. As a result, this hybrid approach succeeds in maximizing the network revenue through significantly increasing the number of concurrently serviced connections while guaranteeing their Quality of Service (QoS) standards. [ABSTRACT FROM AUTHOR]

CO can be stored in geological media for hundreds to thousands of years depending on the location and trapping mechanism(s) involved. A saline aquifer presents the largest capacity available for CO storage among all geological storage options. Two main methodologies proposed by the Department of Energy, US (DOE) and carbon sequestration leadership forum (CSLF) are used for capacity estimation of geological locations for CO storage. A study conducted by Global CCS Institute in 2010 identified 80 large scale integrated projects which will prove to be a huge step in building confidence and commercialization of storage projects in the near future. Use of reliable monitoring tools and accurate simulation software is a must for safe and cost-effective CO storage. [ABSTRACT FROM AUTHOR]

In this letter, capacity estimation for Mobile Ad hoc NETworks (MANETs) using directional antennas are studied. Two Matrix-based Fast Calculation Algorithms (MFCAs) are proposed to estimate the network capacity in a network scenario in which there is no channel sharing among multiple sessions and traffic is sensitive to delay with an end-to-end delay constraint. The first algorithm MFCA-1 is used to estimate network capacity in a situation where all links have the same delay. It estimates the maximum number of κ-hop sessions in a network based on the κ-hop adjacency matrix of the network. The second algorithm MFCA-2 is used to estimate network capacity in a situation where different links may have different delays. It calculates the maximum number of sessions in a network with an end-to-end delay constraint based on the adjacency matrix and the link-delay matrix of the network. Numerical and simulation results show that both MFCA-1 and MFCA-2 can calculate network capacity much faster than the well-known Brute-Force Search Algorithm (BFSA) but with the same accuracy. [ABSTRACT FROM AUTHOR]

This paper is concerned with capacity estimation in multiple-chip-rate (MCR)DS/CDMA systems supporting multimedia services with different informationrates and quality requirements. Considering both power spectral density (PSD)over a radio frequency (RF) band and the effect of RF input filtering onthe receiver, capacity that satisfies the requirementof the bit energy-to-interference PSD ratio is derived.The optimum value of the received power which causes the leastinterference for other users while maintaining an acceptablequality-of-service(QoS) requirement is also derived. The results show that system performanceisstrongly affected by a selected channel assignment strategy. Therefore, it is critical to efficiently assign radio resources in MCR-DS/CDMA systems that support high capacity and a low blocking rate. [ABSTRACT FROM AUTHOR]