Positioning based information technique in cooperative MIMO-OFDM systems

International audienceFuture Communication networks are tending towards a diverse wireless networking world where the positioning information (PI) could be helpful in different techniques like the dynamic resource allocation. On the other hand, the PI could be widely used for cooperative techniques in the relay and/or routing selection process. In this paper, we propose to use the PI in the selection of the relays and then to apply an efficient double layer distributed space time block code (DLSTBC) scheme between the different relays. Using the amplify and forward (AF) technique, we show that the proposed code is very efficient whatever the transmitted power is. Moreover, we show that the relay selection process based on PI yields very powerful results when compared to the random relay selection (RS) proces

Bit Error Rate Prediction of Coded MIMO-OFDM Systems

International audienceBit error rate (BER) prediction over channel realisations has emerged as an active research area. In this paper, we give analytical signal to interference and noise ratio (SINR) evaluation of MIMO-OFDM systems using an iterative receiver. Using this analytical SINR expression, we propose an accurate BER prediction method based on effective exponential SINR mapping (EESM) method. We show by simulations that our method is independent of the channel realisation and of the MIMO scheme. It is only dependent on the modulation and coding scheme

Robustness of MIMO-OFDM Schemes for Future Digital TV to Carrier Frequency Offset

International audienceThis paper investigates the impact of carrier frequency offset (CFO) on the performance of different MIMO-OFDM schemes with high spectral efficiency for next generation of terrestrial digital TV. We show that all studied MIMO-OFDM schemes are sensitive to CFO when it is greater than 1% of inter-carrier spacing. We show also that the Alamouti scheme is the most sensitive MIMO scheme to CF

On the Influence of Carrier Frequency Offset and Sampling Frequency Offset in MIMO-OFDM Systems for Future Digital TV

International audienceThis paper investigates the impact of carrier frequency offset (CFO) and sampling frequency offset (SFO) on the performance of different MIMO-OFDM schemes with high spectral efficiency for next generation of terrestrial digital TV. We analyze particularly orthogonal Alamouti scheme, and non-orthogonal (NO) schemes like VBLAST, linear dispersion (LD) code and Golden code. This analysis gives a global view on the best suitable MIMO-OFDM scheme with respect to CFO and SFO. We show that for high spectral efficiency, Alamouti is more sensitive to CFO and SFO. Moreover, we show that all studied MIMO-OFDM schemes are sensitive to CFO when it is greater than 1% of inter-carrier spacing. Their sensitivity due to SFO is less than that due to CFO

3D MIMO Scheme for Broadcasting Future Digital TV in Single Frequency Networks

International audienceThis letter introduces a 3D space-time-space block code for future digital TV systems. The code is based on a double layer structure for inter-cell and intra-cell transmission mode in single frequency networks. Without increasing the complexity of the receiver, the proposed code is very efficient for different transmission scenarios

Adaptive resources allocation at the cell border using cooperative technique

National audienceThe technique of cooperative communication has recently gained momentum in the research community; this technique utilizes the notion of relay, as an intermediate node between the source and the destination, to enhance the overall system performance. In this paper we ex-plored the benefits of adaptive cooperation, in which the relay adapts its relaying process in response to channel conditions and data priorities. We are particularly interested in applying this concept to the cell border situation, in which two mobile nodes acting as destinations com-municate with base stations (sources) through a relay. The adaptive cooperation is proposed here since the transmission channel conditions (Packet Error Rate for example) and data priori-ties are not the same for both mobiles. We show that using the adaptive resource allocation technique in combination with the cross layer design techniques, we can achieve Real-Time data constraints with no additional overhead

An outer approximation bi-level framework for mixed categorical structural optimization problems

In this paper, mixed categorical structural optimization problems are investigated. The aim is to minimize the weight of a truss structure with respect to cross-section areas, materials and cross-section type. The proposed methodology consists of using a bi-level decomposition involving two problems: master and slave. The master problem is formulated as a mixed integer linear problem where the linear constraints are incrementally augmented using outer approximations of the slave problem solution. The slave problem addresses the continuous variables of the optimization problem. The proposed methodology is tested on three different structural optimization test cases with increasing complexity. The comparison to state-of-the-art algorithms emphasizes the efficiency of the proposed methodology in terms of the optimum quality, computation cost, as well as its scalability with respect to the problem dimension. A challenging 120-bar dome truss optimization problem with 90 categorical choices per bar is also tested. The obtained results showed that our method is able to solve efficiently large scale mixed categorical structural optimization problems.Comment: Accepted for publication in Structural and Multidisciplinary Optimization, to appear 202

Heparin-induced thrombocytopenia presenting as splenic hemorrhage following cardiac surgery: a case report.

BACKGROUND: Heparin-induced thrombocytopenia with thrombosis (HITT) is a paradoxical prothrombotic complication of anticoagulant therapy. As many as 3% of patients undergoing cardiac surgery develop clinical HIT presenting as thrombocytopenia with or without thrombosis within 5-10 days of heparin exposure. Thrombotic complications associated with HIT carry a mortality rate of 5-10%. CASE PRESENTATION: We report a case of atraumatic splenic hemorrhage due to splenic vein thrombosis as the main indicator of HIT following cardiac surgery in a 62-year-old woman. She presented to the emergency department on day nine following coronary artery bypass graft surgery with acute weakness, dizziness, and malaise. Her evaluation in the emergency department found anemia and thrombocytopenia. A coagulation profile revealed a markedly elevated d-dimer. She underwent a computed tomography scan of the chest, abdomen and pelvis for suspected bleed and was found to have splenic vein thrombosis, right atrial filling defects consistent with atrial thrombus and mild to moderate hemoperitoneum. Surgical consultation was obtained due to splenic hemorrhage. Hematology was consulted on post-operative day 10, however, she unfortunately developed left sided weakness concerning for stroke. A magnetic resonance imaging scan of the brain demonstrated infarct involving distribution of the right anterior cerebral artery. A transesophageal echocardiogram demonstrated a large immobile thrombus within the right atrium with a second, mobile thrombus arising from the left tricuspid valve annulus. Due to a 4Ts score of 7 and markedly positive platelet factor 4 (PF4) IgG antibody a serotonin release assay was not performed given the high probability of HIT. She was cautiously treated with bivalirudin and was transitioned to warfarin anticoagulation. In the following days her platelet count recovered and 3 months later a transthoracic echocardiogram revealed solution of the intracardiac thrombi. CONCLUSIONS: Atraumatic splenic hemorrhage is an unusual presentation of HIT that is reminiscent of the rare bilateral adrenal hemorrhage due to adrenal necrosis that also occurs in HIT. Alternative anticoagulation is the mainstay of therapy for HIT despite hemorrhage, given the underlying acquired hypercoagulability. Despite similarities of the presentation between splenic hemorrhage and bilateral adrenal hemorrhage, splenic hemorrhage is rarely described in the literature. HIT should be considered in patients presenting with thrombocytopenia following cardiac surgery

Session 5: Banking, Capital Markets, and The Crypto Revolution - A Look Back and Projection of the Future of FinTech

In Session Five of the SITIE 2023 Symposium: Enabling Innovation in Law and Society, Joseph M. Vincent moderated as the four panelists, Joseph R. Cutler, Lawrence Kaplan, Youssef Sneifer, and Jill Williamson, discussed banking, capital markets, and the crypto revolution by looking back and projecting the future of the financial technology (FinTech) industry. The discussion commenced with a conversation on banking deposits, then moved into a discussion on cryptocurrency companies and the challenges they have faced in recent years in the banking industry. The panelists further discussed artificial intelligence (AI) technology’s impact on FinTech, open banking, and challenges facing cryptocurrency (crypto) going forward