Low-complexity structures for digital symbol timing recovery

Symbol timing recovery (STR) is required in every digital synchronous communications receiver, since the output of the demodulator must be sampled periodically at symbol rate, at the precise sampling time instants in order to correctly recover the transmitted data. The major objective of this thesis is to present, analyze and prove feasibility of the new, low complexity, digital implementation structures for STR. The first presented digital structure is a feedback (FB) symbol timing recovery technique, which is based on the Costas loop principle. This technique requires only 5 constant multipliers and 7 adders, and has very low jitter feature, which is very desirable for high level modulation techniques. The structure, with its error tracking capabilities, is perfectly applicable for continuous mode communication systems, however, the required long acquisition time, makes this feedback STR not suitable for short burst mode communication systems. The feedforward (FF) STR techniques, have very short acquisition time, thus they are the perfect candidates for the short burst mode communication systems, and two such FF techniques are presented in this thesis as well. The first presented FF technique uses relatively high symbol over-sampling (16 samples per symbol) to achieve low implementation complexity (2 unsigned adders, 1 RAM block, and 1 serial magnitude comparator), and acceptable jitter, with the help of only 4 symbols long training preamble. Due to high over-sampling rate, the technique is only applicable to communication systems with relatively low bit rate. In order to expand the applicability of this new over-sampling, technique to higher bit rate systems, an optional "add-on" interpolation technique is presented, which can effectively reduce the over-sampling rate to a minimum of 3 samples per symbol. The cost for the improved performance is in the increased implementation complexity (additional 3 summers and 1 divider

Welke maatregelen kan de gemeente Zwolle treffen om haar primair- en voortgezet onderwijsinstellingen te verduurzamen

Het doel van dit onderzoek is het in kaart brengen van maatregelen waarmee de energieprestaties en binnenmilieu van onderwijsinstellingen verbeterd kunnen worden. Maatschappelijk vastgoed is een breed begrip, dit onderzoek zal zich daarom richten op onderwijsinstellingen. De FAME groep richt zich specifiek op het segment onderwijsinstellingen, vandaar dat het onderzoek gefocust wordt op dit segment. In de oriëntatie worden de werkzaamheden en de belangen van de FAME groep nader toegelicht. De probleemstelling in dit onderzoek zal zijn: Welke maatregelen kan de gemeente Zwolle treffen om haar primair, speciaal en voortgezet onderwijsinstellingen te verduurzamen. Studentenonderzoek in het kader van het thema Duurzaam bouwen

E-learning : technology in teaching logistics

The impact of data, information, and knowledge on teaching and learning is more important than ever. The dynamic development of technology based on digitization, robotization, and networking is transforming the world of business and science, and universities play an extremely important role in this process. The digitization of the socioeconomic environment forces changes towards technologization. The educational process should be substantive and organized in such a way that students not only learn about technological solutions but also have the skills and competences to apply knowledge in practice. An example of such activity is the teaching and learning of logistics with the use of distance learning methods and techniques. The aim of this article is to identify the possibilities of using e-learning in teaching logistics to face the challenges of the future. The information is based on secondary and primary sources. This article uses qualitative and quantitative mixed research methods. On the one hand, books and reports, scientific articles, and Internet sources were examined during the desk research phase. On the other hand, the use of e-learning in teaching logistics at selected universities in Poland was tested using the diagnostic survey method, which involved computer-assisted web interviewing (CAWI). The collected material showed the need for using e-learning in teaching logistics. Logistics companies need employees with digital competences and skills. Therefore, using new technologies already in the education process is justified. Learning with the use of remote methods and techniques represents the essential components of the requirements of the university's technological ecosystem. The analysis of the material leads to the conclusion that the implementation of technology into the didactic process as such is not sufficient. Adoption of modern methods and technologies requires a comprehensive approach to managing educational units. It is important that the propagation of modern forms of teaching has the understanding and support of users who are an inherent component of the educational ecosystem structure

Multi-Agent Reinforcement Learning for Joint Channel Assignment and Power Allocation in Platoon-Based C-V2X Systems

We consider the problem of joint channel assignment and power allocation in underlaid cellular vehicular-to-everything (C-V2X) systems where multiple vehicle-to-infrastructure (V2I) uplinks share the time-frequency resources with multiple vehicle-to-vehicle (V2V) platoons that enable groups of connected and autonomous vehicles to travel closely together. Due to the nature of fast channel variant in vehicular environment, traditional centralized optimization approach relying on global channel information might not be viable in C-V2X systems with large number of users. Utilizing a reinforcement learning (RL) approach, we propose a distributed resource allocation (RA) algorithm to overcome this challenge. Specifically, we model the RA problem as a multi-agent system. Based solely on the local channel information, each platoon leader, who acts as an agent, collectively interacts with each other and accordingly selects the optimal combination of sub-band and power level to transmit its signals. Toward this end, we utilize the double deep Q-learning algorithm to jointly train the agents under the objectives of simultaneously maximizing the V2I sum-rate and satisfying the packet delivery probability of each V2V link in a desired latency limitation. Simulation results show that our proposed RL-based algorithm achieves a close performance compared to that of the well-known exhaustive search algorithm.Comment: 6 pages, 4 figure

Bezpieczeństwo informacji i biznesu: zagadnienia wybrane

Praca recenzowana / peer-reviewed paperPrezentowane wydawnictwo stanowi plon obrad międzynarodowej konferencji naukowej zorganizowanej w dniach 12–13 października 2008 roku przez Katedrę Zarządzania Informacją, działającą w ramach Wydziału Ekonomii i Zarządzania, oraz, jak już wspomniano, przez Międzynarodowe Stowarzyszenie „Edukacja dla Obronności i Bezpieczeństwa”. Ambicją organizatorów konferencji było włączenie w tok dyskusji licznych przedstawicieli organów administracji państwa i samorządu, praktyki gospodarczej, nauki, mediów oraz studentów, zarówno z kraju, jak i z zagranicy

Subdivision of the helix-turn-helix GntR family of bacterial regulators in the FadR, HutC, MocR, and YtrA subfamilies

Haydon and Guest (Haydon, D. J, and Guest, J. R. (1991) FEMS Microbiol Lett. 63, 291-295) first described the helix-turn-helix GntR family of bacterial regulators. They presented them as transcription factors sharing a similar N-terminal DNA-binding (D-b) domain, but they observed near-maximal divergence in the C-terminal effector-binding and oligomerization (E-b/O) domain. To elucidate this C-terminal heterogeneity, structural, phylogenetic, and functional analyses were performed on a family that now comprises about 270 members. Our comparative study first focused on the C-terminal E-b/O domains and next on DNA-binding domains and palindromic operator sequences, has classified the GntR members into four subfamilies that we called FadR, HutC, MocR, and YtrA. Among these subfamilies a degree of similarity of about 55% was observed throughout the entire sequence. Structure/function associations were highlighted although they were not absolutely stringent. The consensus sequences deduced for the DNA-binding domain were slightly different for each subfamily, suggesting that fusion between the D-b and E-b/O domains have occurred separately, with each subfamily having its own D-b domain ancestor. Moreover, the compilation of the known or predicted palindromic cis-acting elements has highlighted different operator sequences according to our subfamily subdivision. The observed C-terminal E-b/O domain heterogeneity was therefore reflected on the DNA-binding domain and on the cis-acting elements, suggesting the existence of a tight link between the three regions involved in the regulating process.Peer reviewe

Locus coeruleus imaging as a biomarker for noradrenergic dysfunction in neurodegenerative diseases.

Pathological alterations to the locus coeruleus, the major source of noradrenaline in the brain, are histologically evident in early stages of neurodegenerative diseases. Novel MRI approaches now provide an opportunity to quantify structural features of the locus coeruleus in vivo during disease progression. In combination with neuropathological biomarkers, in vivo locus coeruleus imaging could help to understand the contribution of locus coeruleus neurodegeneration to clinical and pathological manifestations in Alzheimer's disease, atypical neurodegenerative dementias and Parkinson's disease. Moreover, as the functional sensitivity of the noradrenergic system is likely to change with disease progression, in vivo measures of locus coeruleus integrity could provide new pathophysiological insights into cognitive and behavioural symptoms. Locus coeruleus imaging also holds the promise to stratify patients into clinical trials according to noradrenergic dysfunction. In this article, we present a consensus on how non-invasive in vivo assessment of locus coeruleus integrity can be used for clinical research in neurodegenerative diseases. We outline the next steps for in vivo, post-mortem and clinical studies that can lay the groundwork to evaluate the potential of locus coeruleus imaging as a biomarker for neurodegenerative diseases.Includes MRC, NIHR, Wellcome Trust, H2020 and FP7

Myelin insulation as a risk factor for axonal degeneration in autoimmune demyelinating disease

Axonal degeneration determines the clinical outcome of multiple sclerosis and is thought to result from exposure of denuded axons to immune-mediated damage. Therefore, myelin is widely considered to be a protective structure for axons in multiple sclerosis. Myelinated axons also depend on oligodendrocytes, which provide metabolic and structural support to the axonal compartment. Given that axonal pathology in multiple sclerosis is already visible at early disease stages, before overt demyelination, we reasoned that autoimmune inflammation may disrupt oligodendroglial support mechanisms and hence primarily affect axons insulated by myelin. Here, we studied axonal pathology as a function of myelination in human multiple sclerosis and mouse models of autoimmune encephalomyelitis with genetically altered myelination. We demonstrate that myelin ensheathment itself becomes detrimental for axonal survival and increases the risk of axons degenerating in an autoimmune environment. This challenges the view of myelin as a solely protective structure and suggests that axonal dependence on oligodendroglial support can become fatal when myelin is under inflammatory attack

Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires

The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of $t\overline{t}$, $W+b\overline{b}$ and $W+c\overline{c}$ is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 $\pm$ 0.02 \mbox{fb}^{-1}. The $W$ bosons are reconstructed in the decays $W\rightarrow\ell\nu$, where $\ell$ denotes muon or electron, while the $b$ and $c$ quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions