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The development of electric vehicle (EV) industry is facing a series of issues, among which the efficient charging of multiple EVs needs solving desperately. This paper investigates the coordinated charging of multiple EVs with the aim of reducing the charging cost, ensuring a high battery state of charge (SoC), and avoiding the transformer overload. To this end, we first formulate the EV coordinated charging problem with the above multiple objectives as a Markov Decision Process (MDP) and then propose a multi-agent deep reinforcement learning (DRL)-based algorithm. In the proposed algorithm, a novel interaction model, i.e., communication neural network (CommNet) model, is adopted to realize the distributed computation of global information (namely the electricity price, the transformer load, and the total charging cost of multiple EVs). Moreover, different from the most existing works which make specific constraints on the size, the location, or the topology of the distribution network, what we need in the proposed method is only the transformer load. Besides, due to the use of long and short-term memory (LSTM) for price prediction, the proposed algorithm can flexibly deal with various uncertain price mechanisms. Finally, simulations are presented to verify the effectiveness and practicability of the proposed algorithm in a residential charging area. [ABSTRACT FROM AUTHOR]

The stability and dispersion analysis for the alternating-direction-implicit finite-difference time-domain (ADI-FDTD) method in lossy media is presented. Although the stability and numerical dispersion have been analyzed for the ADI-FDTD method, most of the analysis is dedicated to the cases of lossless media. Here, the stability and dispersion analysis is performed for the method in lossy media. The stability analysis theoretically proves the unconditional stability of the ADI-FDTD method in lossy media. Meanwhile, the dispersion analysis reveals the numerical loss and dispersion characteristics of this method. This will be meaningful for the evaluation and further development of the ADI-FDTD method in lossy media. Index Terms--Alternating-direction-implicit finite-difference time-domain (ADI-FDTD), lossy media, numerical dispersion, stability, unconditionally stable.

From the stability analysis for the conventional explicit finite-difference time-domain (FDTD) method including the passive lumped element, one can find that its stability is related either to the mesh size or to both the mesh size and the values of the elements. This paper presents a three-dimensional (3-D) alternating-direction-implicit FDTD (ADI-FDTD) method, including various lumped elements, such as resistors, capacitors, and inductors. The stability of these schemes is proved to be neither related to the mesh size, nor to the values of the elements. This unconditional stability is different from that of the previous explicit schemes including lumped elements and is therefore a distinct advantage. These 3-D schemes can be justified to achieve improved computation efficiency. Some numerical experiments are performed for the demonstration of the higher efficiency and validation of these schemes. Index Terms--ADI-FDTD, lumped elements, stability.

This paper presents a parameter optimized alternating direction implicit (ADI) finite-difference time-domain (FDTD) method based on the (2,4) stencil (denoted as (2,4) parameter optimized (PO)-ADI-FDTD method) to achieve better dispersion performance. With different optimization schemes, the method can be applied to satisfy various requirements, such as zero numerical dispersion error (ZNDE) in the axes direction, ZNDE in the diagonal direction, zero anisotropy dispersion, ZNDE for two arbitrary angles, and minimum average dispersion error. Through the stability analysis for the (2,4) PO-ADI-FDTD method, it can be proved that all the schemes proposed here are unconditionally stable. The variation of the performance of the (2,4) PO-ADI-FDTD method for different frequencies is also studied. One can find that the desired performance of the (2,4) PO-ADI-FDTD method can be basically preserved within a frequency band without deterioration. Through comparison, it can be concluded that the (2,4) PO-ADI-FDTD method outperforms the previous parameter optimized ADI-FDTD method based on the (2,2) stencil in several aspects. Index Terms--Alternating direction implicit finite-difference time-domain (ADI-FDTD), numerical dispersion, parameter optimized (PO).

In this paper, the stability and dispersion analysis for higher order three-dimensional (3-D) alternating-direction-implicit (ADI) finite-difference time-domain (FDTD) methods is presented. Starting with the stability and dispersion analysis of the fourth order 3-D ADI-FDTD method, which adopts the fourth order cell-centered finite difference scheme for the spatial differential operator, we generalize the analysis to other higher order methods based on the sixth and tenth order cell-centered finite difference schemes. To the best of our knowledge, this is the first time that a comprehensive study of the stability and dispersion characteristics for one series of higher order 3-D ADI-FDTD methods is presented. Our analysis results show that all the higher order ADI-FDTD methods that are based on cell-centered finite difference schemes are unconditionally stable. The generalized form of the dispersion relations for these unconditionally stable ADI-FDTD methods is also presented. Using the relations attained, the effects of the order of schemes, mesh size and time step on the dispersion are illustrated through numerical results. This study will be useful for the selection and evaluation of various higher order ADI methods. Index Terms--Alternating-direction-implicit (ADI), finite-difference time-domain (FDTD), higher order, numerical dispersion relation, stability.

This article investigates a bounded cluster synchronization problem of dynamical systems, which can be of the generic linear type or Lipschitz nonlinear type, over directed switching network. Each cluster is equipped with a virtual leader which produces the desired trajectory for the agents to track. It is required only a fraction of systems is influenced by the leader. The interaction topology, which describes the information exchange among the dynamical systems as well as the virtual leaders, is allowed to be time varying with a well-defined average over an infinite horizon. That is, each augmented cluster, consisting of the agents as well as the corresponding virtual leader, in the time-average network topology is required to have a directed spanning tree. We then transform the cluster synchronization problem into a stability problem via the averaging method. It is proved that the convergence property for both types of dynamical systems is exclusively determined by the averaging system if the network topology switches sufficiently fast compared to original systems. Finally, it is concluded that if the intracluster coupling strength of the time-average topology is stronger than a threshold, then bounded cluster synchronization can be realized for a fast switching linear or nonlinear systems. Two examples are provided to verify our results. [ABSTRACT FROM AUTHOR]

The authors provide evidence that upholds the belief that excitotoxicity may be an element in the development of Alzheimer's disease. Excitotoxicity is a form of nerve injury involving overactivation of glutamate receptors, which, in turn, overloads the cells with calcium.

The resilient cooperative source seeking problem of double-integrator multi-robot systems under d-local deception attacks is investigated. In this article, we first propose a resilient cooperative control algorithm and present a necessary and sufficient condition for its achievement of resilient consensus. Then, through applying the particle swarm optimization algorithm to the resilient cooperative control algorithm, a resilient cooperative source seeking algorithm is proposed. We show that this algorithm can solve the source seeking problems under d-local deception attacks with an additional potential of addressing the multiple local extrema case. Finally, the feasibility of the proposed algorithms is illustrated by simulation and experimental results. [ABSTRACT FROM AUTHOR]

Summary: This article considers distributed optimization problems of complex cyber‐physical networks, whose goal is to minimize a global function consisting of a sum of local functions possessed by each node, when the communication network is suffering L‐local deception attacks. After showing that merely 1‐local deception attacks can arbitrarily affect the outcome of any distributed optimization algorithms without being detected, we propose a resilient consensus‐based distributed optimization algorithm, where the estimation for the optimizer of each node is updated according to its subgradient and its partial neighbors' estimation. Then, we provide the conditions for the proposed algorithm to ensure that all the nodes can make an agreement and converge to the convex hull of the local optimizer of their functions in the presence of L‐local deception attacks. Finally, some simulation examples are presented to demonstrate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

This article considers the resilient consensus problems of discrete-time complex cyber-physical networks under $F$ -local deception attacks. A resilient consensus algorithm, where extreme values received are removed by each node, is first introduced. By utilizing the presented algorithm, a necessary and sufficient condition to ensure resilient consensus in the absence of trusted edges is then provided by means of network robustness. We further generalize the notion of network robustness and present the necessary and sufficient condition for the achievement of resilient consensus in the presence of trusted edges. In addition, we show that through appropriately assigning the trusted edges, the resilient consensus can be reached under arbitrary communication network. Finally, the validity of the theoretical findings is demonstrated by simulation examples. [ABSTRACT FROM AUTHOR]

This paper investigates the group synchronization problem for interacting clusters of agents, which can be either generic linear systems or nonlinear oscillators, by focusing on in-depth understanding of how the couplings among agents influence the group behavior. To this end, we work on both the homogeneous case that agents have the same system dynamics and the heterogeneous case that agents from different clusters have different system dynamics. It is shown that the synchronization for each cluster of agents is irrelevant to the strength of the intercluster couplings as long as the intercluster couplings are collectively acyclic; that is, the intercluster couplings do not incur desynchronization and, thus, no extra effort beyond the strengths of the intracluster couplings, which are necessary to guarantee the synchronization of each cluster in the absence of intercluster couplings, are needed. Moreover, we provide an example demonstrating that the condition of having collectively acyclic intercluster couplings is not a necessity in guaranteeing the above property. [ABSTRACT FROM AUTHOR]

In order to investigate the diversity of spotted fever group (SFG) Rickettsia infection in hard ticks, ticks were harvested from the forest areas in Suifenhe city, along the Chinese–Russian border and conventional PCR was carried out using universal SFG Rickettsia primers targeting glt A and omp A genes to screen for their infection with SFG Rickettsia organisms. Results showed that of the 215 ticks belonging to Ixodes persulcatus , Haemaphysalis concinna and Haemaphysalis japonica Warburton, 1908 species, 138 (64.2%) were positive for SFG Rickettsia . Three species of SFG Rickettsia were detected, Rickettsia raoultii , Rickettsia heilongjiangensis and Candidatus Rickettsia tarasevichiae . No co-infection with different species of SFG Rickettsia was found in any individual tick among the three tick species. We detected more than one SFG Rickettsia species in ticks from each of the three tick species with an overlapping distribution and potentially similar transmission cycles of SFG Rickettsia in the areas surveyed. Consequently, different pathogenic rickettsial species may be involved in human cases of rickettsiosis after a bite of the three above-mentioned tick species in that area Rickettsia [ABSTRACT FROM AUTHOR]

Chronic infection with Schistosoma japonicum is an important cause of hepatic fibrosis (HF). Human 9q33.3 is one of the most important loci for stress-related diseases. We examined the potential associations of 43 single-nucleotide polymorphisms (SNPs) with S. japonicum infection and HF in epidemic region in China. We identified a SNP (rs10118570 GG in mitogen-activated protein kinase associated protein 1, MAPKAP1) contributes to anti-infection (adjusted OR = 0.35) and anti-fibrogenesis (adjusted RR = 0.44) in the discovery study. Replicative and combined studies showed consistent protective quality for this genotype (replicative: adjusted OR = 0.37 for anti-infection, and adjusted RR = 0.40 for anti-fibrogenesis; Combined: adjusted OR = 0.45 for anti-infection, and adjusted RR = 0.42 for anti-fibrogenesis). Univariate and multivariate analysis in the discovery, replicative and combined studies, suggested that durations (years), splenomegaly, serum ALB and rs10118570 were independent predictors influencing the fibrogenesis. The analysis of gene-gene interaction showed rs10118570 functions independently. We conclude that MAPKAP1 may represent a novel anti-infection and anti-fibrogenesis genomic locus in chronic schistosomiasis japonica. And rs10118570 may be a potential biomarker and target for the treatment of this life-threatening ancient disease. [ABSTRACT FROM AUTHOR]

Background: Endoscopic third ventriculostomy (ETV) is a developing therapeutic stratagem for obstructive hydrocephalus (OH). The aim of this study was to determine the relevance of third ventricle diagnostic imaging by three-dimensional constructive inference in steady state (3D CISS) MRI in patients with OH and to access the preoperative and postoperative values of this technique in patients undergoing endoscopic third ventriculostomy (ETV). Methods: Forty-six patients with an existing obstruction below the posterior part of the third ventricle underwent 3D CISS sequence MRI on a 1.5 T superconductive MR scanner and were included into this retrospective study. 19 patients were treated with ETV. Regression analysis of the correlation between third ventricle enlargement (TVE) and hydrocephalus degree (HD) and between TVE and third ventricle floor thickness (TVFT) was calculated. In the 19 ETV cases the incisions were marked according to MR images, and the 3D-CISS sequence imaging and the surgical outcome were compared before and after ETV. Results: By virtue of 3D-CISS 97.83% third ventricle floors and 91.30% basilar arteries (BA) could be visualized, and there was a positive correlation between TVE and HD and a negative correlation between TVE and TVFT in this group. All incision sites on the scalp could be marked correctly. The degree of enlargement of the third ventricle allowed a prediction of the technical challenge to puncture the third ventricle floor. The position and route of BA could be demonstrated avoiding intraoperative iatrogenic lesions. At follow-up, 100% of the fistulas of the third ventricle floor could be measured on 3D-CISS images. The mean diameter of the fistulas was 6.12 ± 0.96 mm; in 91.67%, new CSF fluid directions could be demonstrated; in 83.33%, enlarged ventricle system got withdrawn, and 91.67% patients showed relief of initial symptoms. 1 patient needed the implantation of a ventriculoperitoneal shunt 7 months after EVT. The preoperative HD compared with postoperative HD (P < .01); the preoperative TVE compared with postoperative TVE (P < .05). Conclusion: Images of the 3D-CISS sequence on MRI can visualize the third ventricle accurately and provide a reliable method for the evaluation of ETV pre- and postoperatively. The degree of enlargement of the third ventricle in patients with obstructive hydrocephalus is associated with the thickness of third ventricle floor and allows a prediction of the difficulty to puncture in ETV. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate the effectiveness of the supraorbital "keyhole" approach with endoscope assistance in surgical treatment of benign tumors around the sellar region. Thirty-five patients, including 19 pituitary tumors, 11 craniopharyngiomas and five tuberculum sellae meningiomas, were enrolled in this study. The tumors were resected through an endoscope-assisted supraorbital keyhole approach via a small skin incision within the eyebrow. Complete removal of the sellar region tumors was achieved in all 35 cases by endoscope-assisted supraorbital keyhole approach. Mean length of hospital stay after surgery was 10.2 days (range 5 - 17). There was no patient with evidence of residual or recurrent tumor during the follow-up period. There was no infection, bleeding, further vision impairment, oculomotor nerve injury or other cranial nerve injury symptom owing to surgery. Though some patients suffered from insipidus, hyperprolactinemia, subcutaneous edema or other postoperative complications, they eventually recovered with or without drug administration. The supraorbital "keyhole" approach with endoscopic assistance in the surgical treatment of benign tumors around the sellar region is an ideal pattern. [ABSTRACT FROM AUTHOR]

Telomerase is a reverse transcriptase that adds repeats of a six-base DNA sequence to chromosome ends and thereby prevents their shortening during successive cell divisions. Telomerase activity and expression of the catalytic subunit of telomerase (TERT) are high in brain cells during embryonic development, but are undetectable in the adult. We now report that telomerase activity and expression of TERT are induced in the hippocampus of adult mice after administration of the seizure-inducing excitotoxin kainate. Telomerase activity is present at 24 h and 7 days after kainate administration, but is no longer detectable at 4 weeks. Because the time course of telomerase induction was similar to the time course of microglial activation, we performed studies to determine whether microglia were the source of the telomerase activity. Examination of brain sections immunostained with a TERT antibody and an antibody against a microglia-specific antigen revealed that TERT was not detectable in the uninjured brain, and was present in microglia 24 h and 7 days after kainate administration. This is the first evidence that telomerase can be induced by brain injury and the first evidence that TERT can be expressed in microglia, suggesting roles for telomerase in microglial responses to brain injury. [Copyright &y& Elsevier]

This paper considers the interval consensus problems of discrete-time multi-agent systems over random interaction networks, where each agent can impose a lower and an upper bound, i.e., a local constraint interval, on the achievable consensus value. We show that if the intersection of the intervals is nonempty, it holds as a sure event that the states of all the agents converge to a common value inside that intersection, i.e., the interval consensus can be achieved almost surely. Convergence analysis is performed through developing a robust consensus analysis of random networks in view of a martingale convergence lemma. Numerical examples are also exhibited to verify the validity of the theoretical results. [ABSTRACT FROM AUTHOR]

A 2D higher-order alternating-direction-implicit (ADI) finite-difference time-domain method based on a compact scheme is presented in this paper. This compact ADI method improves the efficiency of computation by reducing the bandwidth of the matrix to be inversed from seven to five for the 4th-order scheme. The method is proved to be unconditionally stable and its dispersion analysis is also presented. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 273–275, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20609 [ABSTRACT FROM AUTHOR]