Tampere University of Technology

About: Tampere University of Technology is a based out in . It is known for research contribution in the topics: Laser & Context (language use). The organization has 6802 authors who have published 19787 publications receiving 431793 citations. The organization is also known as: Tampereen teknillinen yliopisto.

Yee-like schemes on staggered cellular grids: a synthesis between FIT and FEM approaches

Abstract: We propose an analysis (discretization techniques, convergence) of numerical schemes for Maxwell equations which use two meshes (not necessarily tetrahedral), dual to each other. Schemes of this class generalize Yee's "finite difference in time domain" method (FDTD). We distinguish network equations (the discrete equivalents of Faraday's law and Ampere's relation) which can be set up without any recourse to finite elements, and network constitutive laws, whose validity cannot be assessed without them. This establishes a complementarity between "finite integration techniques" (FIT) and the finite element method (FEM). As an example, a Yee-like method on a simplicial mesh and its so-called "orthogonal" dual, is described, and its convergence is proved.

Model studies on ion‐induced nucleation in the atmosphere

Abstract: [1] A new model for ion-induced nucleation and charged aerosol dynamics is presented in this paper. It was found that ion-induced nucleation is able to produce a considerable amount of new particles if the preexisting particle concentration is sufficiently low. Also, when only positive or negative ions nucleate a large amount of particles in observable sizes was produced. It was also found that there can be continuous nucleation in particle sizes below the detection limit of most commonly used aerosol instruments at low temperatures and high preexisting particle concentrations. In some simulated conditions, fair agreement with observed particle formation events in boreal forest environment was achieved. According to the results, in certain situations ion-induced nucleation changes the charge distribution of the particles, which may allow the observation of ion-induced nucleation in the atmospheric conditions.

Modeling Prioritized Broadcasting in Multichannel Vehicular Networks

Abstract: Effective data broadcasting is essential in vehicular networks not only for road-safety message dissemination but also to aid routing and cooperative driving applications through periodic beaconing and to spread network initialization advertisements that are mandatory to support infotainment applications. Broadcast data are neither acknowledged nor retransmitted in case of failure, which raises the possibility of frame loss due to channel errors and collisions with multiple simultaneous broadcasts. This paper aims at modeling periodic broadcasting on the control channel of IEEE Std. 802.11p vehicular networks with multichannel architecture. Unlike previous related work, the proposed novel analytical approach accounts for mutual influence among nodes, frequent periodic updates of broadcasted data, standard network advertisement procedures, and 802.11p prioritized channel access with multichannel-related phenomena under various link quality conditions.

Applying CDMA Technique to Network-on-Chip

Abstract: The issues of applying the code-division multiple access (CDMA) technique to an on-chip packet switched communication network are discussed in this paper. A packet switched network-on-chip (NoC) that applies the CDMA technique is realized in register-transfer level (RTL) using VHDL. The realized CDMA NoC supports the globally-asynchronous locally-synchronous (GALS) communication scheme by applying both synchronous and asynchronous designs. In a packet switched NoC, which applies a point-to-point connection scheme, e.g., a ring topology NoC, data transfer latency varies largely if the packets are transferred to different destinations or to the same destination through different routes in the network. The CDMA NoC can eliminate the data transfer latency variations by sharing the data communication media among multiple users concurrently. A six-node GALS CDMA on-chip network is modeled and simulated. The characteristics of the CDMA NoC are examined by comparing them with the characteristics of an on-chip bidirectional ring topology network. The simulation results reveal that the data transfer latency in the CDMA NoC is a constant value for a certain length of packet and is equivalent to the best case data transfer latency in the bidirectional ring network when data path width is set to 32 bits.

Innate immune activity is detected prior to seroconversion in children with HLA-conferred type 1 diabetes susceptibility

Abstract: The insult leading to autoantibody development in children who will progress to develop type 1 diabetes (T1D) has remained elusive. To investigate the genes and molecular pathways in the pathogenesis of this disease, we performed genome-wide transcriptomics analysis on a unique series of prospective whole-blood RNA samples from at-risk children collected in the Finnish Type 1 Diabetes Prediction and Prevention study. We studied 28 autoantibody-positive children, out of which 22 progressed to clinical disease. Collectively, the samples covered the time span from before the development of autoantibodies (seroconversion) through the diagnosis of diabetes. Healthy control subjects matched for date and place of birth, sex, and HLA-DQB1 susceptibility were selected for each case. Additionally, we genotyped the study subjects with Immunochip to identify potential genetic variants associated with the observed transcriptional signatures. Genes and pathways related to innate immunity functions, such as the type 1 interferon (IFN) response, were active, and IFN response factors were identified as central mediators of the IFN-related transcriptional changes. Importantly, this signature was detected already before the T1D-associated autoantibodies were detected. Together, these data provide a unique resource for new hypotheses explaining T1D biology.