Distributed state estimation for uncertain Markov-type sensor networks with mode-dependent distributed delays

This the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2012 John Wiley & Sons, Ltd.In this paper, the distributed state estimation problem is investigated for a class of sensor networks described by uncertain discrete-time dynamical systems with Markovian jumping parameters and distributed time-delays. The sensor network consists of sensor nodes characterized by a directed graph with a nonnegative adjacency matrix that specifies the interconnection topology (or the distribution in the space) of the network. Both the parameters of the target plant and the sensor measurements are subject to the switches from one mode to another at different times according to a Markov chain. The parameter uncertainties are norm-bounded that enter into both the plant system as well as the network outputs. Furthermore, the distributed time-delays are considered, which are also dependent on the Markovian jumping mode. Through the measurements from a small fraction of the sensors, this paper aims to design state estimators that allow the nodes of the sensor network to track the states of the plant in a distributed way. It is verified that such state estimators do exist if a set of matrix inequalities is solvable. A numerical example is provided to demonstrate the effectiveness of the designed distributed state estimators.This work was supported in part by the Royal Society of the U.K., the National Natural Science Foundation of China under Grants 60804028 and 61028008, the Specialized Research Fund for the Doctoral Program of Higher Education for New Teachers in China under Grant 200802861044, the Teaching and Research Fund for Excellent Young Teachers at Southeast University of China, the International Science and Technology Cooperation Project of China under Grant No. 2009DFA32050, and the Alexander von Humboldt Foundation of Germany

Performance Analysis and Optimization of IEEE 802.11 Protocol in Wireless Ad Hoc Networks

作为新一代无线通信网络的核心技术之一，无线自组织网络技术已成为当前信息技术领域的一大研究热点。作为无线自组织网络的关键技术，媒体接入控制（MediumAccessControl，MAC）协议决定着无线信道的使用方式，并负责为节点分配无线通信资源，其性能的优劣直接影响无线信道的利用率和网络的整体性能。其中，IEEE802.11的MAC协议是目前无线自组织网络的测试系统和实际应用中使用最多的MAC协议之一，也是许多无线自组织网络MAC协议的研究基础。因此，系统研究IEEE802.11的性能并加以针对性的改进，具有极为重要的理论意义和广泛的应用价值。 IEEE802.11MAC协议以分布式协调功能...As one of the essential technologies of next generation mobile communication system, wireless Ad Hoc network has become the focus in the field of current information technologies. As the key component of wireless Ad Hoc networks, Media Access Control (MAC) protocols determine the usage mode of wireless channels and allocate radio resource for nodes, which can directly influence the efficiency of w...学位：工学博士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007015387

Structural constraints of pyocin S2 import through the ferripyoverdine receptor FpvAI

TonB-dependent transporters (TBDTs) mediate energized transport of essential nutrients into gram-negative bacteria. TBDTs are increasingly being exploited for the delivery of antibiotics to drug-resistant bacteria. While much is known about ground state complexes of TBDTs, few details have emerged about the transport process itself. In this study, we exploit bacteriocin parasitization of a TBDT to probe the mechanics of transport. Previous work has shown that the N-terminal domain of Pseudomonas aeruginosa–specific bacteriocin pyocin S2 (PyoS2NTD) is imported through the pyoverdine receptor FpvAI. PyoS2NTD transport follows the opening of a proton-motive force-dependent pore through FpvAI and the delivery of its own TonB box that engages TonB. We use molecular models and simulations to formulate a complete translocation pathway for PyoS2NTD that we validate using protein engineering and cytotoxicity measurements. We show that following partial removal of the FpvAI plug domain which occludes the channel, the pyocin's N-terminus enters the channel by electrostatic steering and ratchets to the periplasm. Application of force, mimicking that exerted by TonB, leads to unraveling of PyoS2NTD as it squeezes through the channel. Remarkably, while some parts of PyoS2NTD must unfold, complete unfolding is not required for transport, a result we confirmed by disulfide bond engineering. Moreover, the section of the FpvAI plug that remains embedded in the channel appears to serve as a buttress against which PyoS2NTD is pushed to destabilize the domain. Our study reveals the limits of structural deformation that accompanies import through a TBDT and the role the TBDT itself plays in accommodating transport

Model-Based Security Testing

Security testing aims at validating software system requirements related to security properties like confidentiality, integrity, authentication, authorization, availability, and non-repudiation. Although security testing techniques are available for many years, there has been little approaches that allow for specification of test cases at a higher level of abstraction, for enabling guidance on test identification and specification as well as for automated test generation. Model-based security testing (MBST) is a relatively new field and especially dedicated to the systematic and efficient specification and documentation of security test objectives, security test cases and test suites, as well as to their automated or semi-automated generation. In particular, the combination of security modelling and test generation approaches is still a challenge in research and of high interest for industrial applications. MBST includes e.g. security functional testing, model-based fuzzing, risk- and threat-oriented testing, and the usage of security test patterns. This paper provides a survey on MBST techniques and the related models as well as samples of new methods and tools that are under development in the European ITEA2-project DIAMONDS.Comment: In Proceedings MBT 2012, arXiv:1202.582

Biomechanical Testing of Spinal Segment Fixed by Arcofix System on the Swine Spine

Study DesignAn in vitro biomechanical study.PurposeTo evaluate the mechanical properties of the spinal segment in the intact, injured, and stabilized state after fixation by an Arcofix implant.Overview of LiteratureSeveral types of thoracolumbar spine injury necessitates anterior instrumentation. The Arcofix plate represents the latest generation of angular stablity systems. The biomechanical properties of these implants have not been sufficiently studied yet.MethodsA total of ten porcine specimens (levels Th12-L3) were prepared. The tests were performed for intact, injured, and implanted specimens. In each state, the specimen was subjected to a tension load of a prescribed force, and subsequently, twisted by a given angle. The force load was 200 N. The torsion load had a deformation character, i.e., the control variable was the twisting angle and the measured variable was the moment of a couple. The amplitude of the load alternating cycle was 3°. Another parameter that was evaluated was the area of the hysteresis loop. The area corresponds to the deformation energy which is dissipated during the cycle.ResultsA statistically significant difference was found between the intact and injured states as well as between the injured and implanted specimens. The statistical evaluation also showed a statistically different value of the hysteresis loop area. In the case of instability, the area decreased to 33% of the physiological value. For the implanted sample, the area increased to 170% of the physiological value.ConclusionsThe Arcofix implant with its parameters appears to be suitable and sufficiently stable for the treatment of the anterior column of the spine

Patient perceptions of anticoagulant treatment with dabigatran or a vitamin K antagonist for stroke prevention in atrial fibrillation according to region and age : an exploratory analysis from the RE-SONANCE study

Funding Information: The authors thank all the patients who participated in this study. Medical writing support was provided by Parexel, with funding from Boehringer Ingelheim GmbH. Funding Information: Dragos Vinereanu received grants and personal fees from Boehringer Ingelheim during the conduct of the study; grants and personal fees from Bristol-Myers Squibb, Pfizer, Bayer, Johnson & Johnson, and Daiichi Sankyo outside the submitted work. Dmitry Napalkov received research grants and has participated in scientific advisory boards for Boehringer Ingelheim and has received speaker’s honoraria from Bayer, Boehringer Ingelheim, Pfizer, and Takeda. Bela Benczur received speaker’s/consultancy fees from Bayer, Berlin-Chemie/Menarini, Boehringer Ingelheim, Krka Pharma, Novartis, Pfizer, Sandoz, and Sanofi. Martin Ciernik, Alexey Medvedchikov, and Wenbo Tang are employees of Boehringer Ingelheim. Pentti Põder received educational grants from Boehringer Ingelheim. Maria Trusz-Gluza received personal fees from Boehringer Ingelheim (null during the conduct of the study), personal fees and non-financial support from Boehringer Ingelheim, and personal fees from Bayer outside the submitted work. Jiří Vesely received personal fees and non-financial support from Bayer, Boehringer Ingelheim, Pfizer, MSD, and PRO.MED.CS outside the submitted work. All other authors report no conflicts of interest. Publisher Copyright: © 2021, The Author(s).Background: The oral anticoagulant dabigatran offers an effective alternative to vitamin K antagonists (VKAs) for stroke prevention in atrial fibrillation (AF), yet patient preference data are limited. The prospective observational RE-SONANCE study demonstrated that patients with AF, newly initiated on dabigatran, or switching to dabigatran from long-term VKA therapy, reported improved treatment convenience and satisfaction compared with VKA therapy. This pre-specified sub-study aimed to assess the impact of country and age on patients’ perceptions of dabigatran or VKA therapy in AF. Methods: RE-SONANCE was an observational, prospective, multi-national study (NCT02684981) that assessed treatment satisfaction and convenience in patients switching from VKAs to dabigatran (Cohort A), or newly diagnosed with AF receiving dabigatran or VKAs (Cohort B), using the PACT-Q questionnaire. Pre-specified exploratory outcomes: variation in PACT-Q2 scores by country and age (< 65, 65 to < 75, ≥ 75 years) (both cohorts); variation in PACT-Q1 responses at baseline by country and age (Cohort B). Results: Patients from 12 countries (Europe/Israel) were enrolled in Cohort A (n = 4103) or B (n = 5369). In Cohort A, mean (standard deviation) PACT-Q2 score increase was highest in Romania (convenience: 29.6 [23.6]) and Hungary (satisfaction: 26.0 [21.4]) (p < 0.001). In Cohort B, mean (standard error) increase in PACT-Q2 scores between dabigatran and VKAs was highest in Romania (visit 3: 29.0 [1.3]; 24.5 [0.9], p < 0.001). Mean PACT-Q2 score increase by age (all p < 0.001) was similar across ages. PACT-Q1 responses revealed lowest expectations of treatment success in Romania and greatest concerns about payment in Estonia, Latvia, and Romania, but were similar across ages. Conclusions: Treatment satisfaction and convenience tended to favor dabigatran over VKAs. Regional differences in treatment expectations exist across Europe. Trial and clinical registry: Trial registration number: ClinicalTrials.gov NCT02684981. Trial registration date: February 18, 2016.publishersversionPeer reviewe

Clinical Experience of Stereotactic Radiosurgery at a Linear Accelerator for Intraocular Melanoma Combined with Iridociliary Tumor Resection: A Case Report

Introduction: The treatment of iridociliary and choroidal melanoma relies on the patient’s systemic health, tumor size, location, related features, state of the opposing eye, and personal preferences. The two categories are radiation and surgical techniques. Transpupillary thermotherapy, plaque radiotherapy, charged particle irradiation, local resection, enucleation, orbital exenteration, and experimental nanoparticle therapy are all options for treating choroidal melanoma. Case Presentation: The method that entails creating a partial thickness circular, rectangular, or polyhedral scleral flap in the region covering the tumor after removing a portion of the extraocular muscles is the most popular method for local excision in choroidal or choroidal-ciliary body cancers. We discuss our experience treating iridociliary melanoma using block excision and stereotactic irradiation on a linear accelerator with TD 20.0 Gy. Conclusion: One of the treatment modalities is the combined treatment approach using stereotactic irradiation and tumor resection, and our results 1 year after therapy are comparable to the rates of local control and anatomic eye preservation to those achieved in studies of comparable uveal melanoma treatment modalities