A New Low Latency Parallel FIR Filter Scheme

A new array type parallel scheme for an FIR digital filter is presented in this paper. The proposed scheme is based on the structure of the carry-save array multiplier where each cell implements the computation of an FIR filter at the bit-level. This structure leads to latency independent of the number of the filter taps. The proposed scheme is pipelined at the bit-level, is systolic at the cell-level and requires less hardware than other schemes based on discrete multipliers.Paraskevas Kalivas received his Diploma and Ph.D. degree in electrical and computer engineering from the National Technical University of Athens, Greece, in 1990 and 2000 respectively.His research interests include computer arithmetic and efficient realization of arithmetic circuits and digital filters.Vassilis Vassilakis received his Diploma in electrical and computer engineering from NationalTechnical University of Athens, Greece, in 1997. He isworking toward the Ph.D. degree in electrical engineering at National Technical University of Athens.His research interests include efficient circuit implemenation of DSP algorithms and java processor architectures.Chris Meletis received his Diploma in electrical and computer engineering from National Technical University of Athens in 1997. Currently, he is working toward the Ph.D. degree in electrical engineering at National Technical University of Athens.His research interests include multirate filter banks, digital filter design and their efficient realization.Kiamal Z. Pekmestzi received his Diploma in electrical engineering from the National Technical University of Athens, Greece, in 1975. From 1975 to 1981, he was a research fellow in the Electronics Department of the Nuclear Research Center Demokritos. He received his Ph.D. in electrical engineering from the University of Patras, Greece, in 1981.From 1983 to 1985, he was a professor at the Higher School of Electronics in Athens. Since 1985, he has been with the National Technical University of Athens, where he is currently a professor. His research interests include computer arithmetic, VLSI digital filters and VLSI design automation.     

Proteome of Stored RBC Membrane and Vesicles from Heterozygous Beta Thalassemia Donors

Genetic characteristics of blood donors may impact the storability of blood products. Despite higher basal stress, red blood cells (RBCs) from eligible donors that are heterozygous for beta-thalassemia traits (βThal⁺) possess a differential nitrogen-related metabolism, and cope better with storage stress compared to the control. Nevertheless, not much is known about how storage impacts the proteome of membrane and extracellular vesicles (EVs) in βThal⁺. For this purpose, RBC units from twelve βThal⁺ donors were studied through proteomics, immunoblotting, electron microscopy, and functional ELISA assays, versus units from sex- and aged-matched controls. βThal⁺ RBCs exhibited less irreversible shape modifications. Their membrane proteome was characterized by different levels of structural, lipid raft, transport, chaperoning, redox, and enzyme components. The most prominent findings include the upregulation of myosin proteoforms, arginase-1, heat shock proteins, and protein kinases, but the downregulation of nitrogen-related transporters. The unique membrane proteome was also mirrored, in part, to that of βThal⁺ EVs. Network analysis revealed interesting connections of membrane vesiculation with storage and stress hemolysis, along with proteome control modulators of the RBC membrane. Our findings, which are in line with the mild but consistent oxidative stress these cells experience in vivo, provide insight into the physiology and aging of stored βThal⁺ RBCs.     

Indexing views to route queries in a PDMS

P2P computing gains increasing attention lately, since it provides the means for realizing computing systems that scale to very large numbers of participating peers, while ensuring high autonomy and fault-tolerance. Peer Data Management Systems (PDMS) have been proposed to support sophisticated facilities in exchanging, querying and integrating (semi-)structured data hosted by peers. In this paper, we are interested in routing graph queries in a very large PDMS, where peers advertise their local bases using fragments of community RDF/S schemes (i.e., views). We introduce an original encoding for these fragments, in order to efficiently check whether a peer view is subsumed by a query. We rely on this encoding to design an RDF/S view lookup service featuring a statefull and a stateless execution over a DHT-based P2P infrastructure. We finally evaluate experimentally our system to demonstrate its scalability for very large P2P networks and arbitrary RDF/S schema fragments, and to estimate the number of routing hops required by the two versions of our lookup service. Work done when T. Dalamagas was a postdoc researcher in NTUA.     

Explicit model predictive control of hybrid systems and multiparametric mixed integer polynomial programming

Hybrid systems are dynamical systems characterized by the simultaneous presence of discrete and continuous variables. Model‐based control of such systems is computationally demanding. To this effect, explicit controllers which provide control inputs as a set of functions of the state variables have been derived, using multiparametric programming mainly for the linear systems. Hybrid polynomial systems are considered resulting in a Mixed Integer Polynomial Programming problem. Treating the initial state of the system as a set of bounded parameters, the problem is reformulated as a multiparametric Mixed Integer Polynomial optimization (mp‐MIPOPT) problem. A novel algorithm for mp‐MIPOPT problems is proposed and the exact explicit control law for polynomial hybrid systems is computed. The key idea is the computation of the analytical solution of the optimality conditions while the binary variables are treated as relaxed parameters. Finally, using symbolic calculations exact nonconvex critical regions are computed. © 2016 The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers AIChE J, 62: 3441–3460, 2016     

A low-cost wireless sensors positioning solution for indoor parking facilities management

A relatively low-cost system for indoor parking facilities management is proposed, which is a combined solution of RFID/WiFi and a MEMS IMU monitoring scheme. An RFID localisation module is proposed in the form of so-called virtual gates. To define such virtual gates, either RFID tags or readers are placed at known locations throughout the area of interest. In this study, a number of tags are fixed at known positions and a moving reader is carried by each participating vehicle. Based on this configuration set-up, the Cell of Origin (CoO) technique is applied, in which the system indicates the presence of the user carrying the reader in a cell around the tag location. To define a virtual gate, tags are installed along the parking lot corridors and at critical transit passages in the parking facility. The CoO technique is also proposed in the case of WiFi for location determination of vehicles in a multi-storey car park. In this study, WiFi is employed to monitor the passing vehicles and bridge the gap until a tag can detect a user’s reader again. Thus, a combined positioning solution of RFID and WiFi is achieved. As a complement to the proposed RFID/WiFi system, this study examines the potential and limitations of MEMS IMU sensors (i.e. accelerometers, gyroscopes and barometers) commonly found in modern smartphones. The paper concludes with a detailed discussion on the implications of alternative positioning techniques for indoor parking management.     

Towards proximity-based passenger sensing on public transport buses

While substantial research on intelligent transportation systems has focused on the development of novel wireless communication technologies and protocols, relatively little work has sought to fully exploit proximity-based wireless technologies that passengers actually carry with them today. This paper presents the real-world deployment of a system that exploits public transit bus passengers’ Bluetooth-capable devices to capture and reconstruct micro- and macro-passenger behavior. We present supporting evidence that approximately 12 % of passengers already carry Bluetooth-enabled devices and that the data collected on these passengers captures with almost 80 % accuracy the daily fluctuation of actual passengers flows. The paper makes three contributions in terms of understanding passenger behavior: We verify that the length of passenger trips is exponentially bounded, the frequency of passenger trips follows a power law distribution, and the microstructure of the network of passenger movements is polycentric.     

Numerical study of confinement effectiveness in solid and hollow reinforced concrete bridge piers: Analysis results and discussion

This paper presents the outcome of a large parametric numerical analysis of solid and hollow reinforced concrete piers taken from actually constructed bridges, based on a consistent three-dimensional nonlinear finite element methodology that was presented in a companion paper. Various transverse reinforcement arrangements and spacings were examined, as well as the effect of high-strength concrete on confinement effectiveness. The interpretation of numerical results mainly focuses on identifying the most convenient confinement configurations in terms of enhanced strength and ductility, as well as ease of construction and cost effectiveness. Furthermore, issues regarding confinement arrangements (often used in practice) that result in reduced section ductility are investigated and possible remedies are suggested. Finally, the broad applicability of the proposed methodology is established by application to a particularly complex (in terms of geometry and reinforcement detailing) hollow pylon section.     

Automotive industry challenges in meeting EU 2015 environmental standard

Automotive Shredder Residue (ASR) generation in EU is approximately 2–2.5 million t/y, constituting 10% of total hazardous waste in the EU. Currently, about 75% of ELVs total weight is recycled while the remaining 25% (ASR). Not surprisingly, Europe is the world’s largest vehicle producer as about 30% of the 50 million cars produced globally are manufactured in the EU. Worldwide, ASR is considered an increasingly problematic waste, consisting of a large number of different materials that basically remains unprocessed and directed to landfills. The aim of this study is to provide an overview of the ASR problem and the options for processing this waste in order to minimize the waste directed to landfills.     

Challenging Hurdles of Current Targeting in Glioblastoma: A Focus on Immunotherapeutic Strategies

Glioblastoma is the most frequent primary neoplasm of the central nervous system and still suffers from very poor therapeutic impact. No clear improvements over current standard of care have been made in the last decade. For other cancers, but also for brain metastasis, which harbors a very distinct biology from glioblastoma, immunotherapy has already proven its efficacy. Efforts have been pursued to allow glioblastoma patients to benefit from these new approaches, but the road is still long for broad application. Here, we aim to review key glioblastoma immune related characteristics, current immunotherapeutic strategies being explored, their potential caveats, and future directions.     

A Low-Complexity PTS-based PAPR Reduction Technique for OFDM Signals without Transmission of Side Information

Increased peak-to-average power ratio (PAPR) imposes a design challenge for orthogonal frequency division multiplexing-based signals. An efficient technique to address the increased PAPR problem is the partial transmit sequences (PTS) approach. A significant drawback of PTS is the fact that it multiplies the transmitted symbol with weighting factors selected by the transmitter. Since the weighting factors are required for decoding, they are explicitly transmitted, in most cases. This paper proposes a new low-complexity technique for retrieving the weighting factors in the receiver. The proposed decoder uses the predefined values of pilot tones and explores all the permissible combinations of weighting factors in order to identify the factor combination employed by the transmitter. The proposed decoder requires no additional pilot tones or explicit transmission of side information, therefore no data rate loss is implied. Furthermore this paper presents a digital very large scale integration implementation of the proposed PTS decoder and demonstrates its low-power properties.