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NoC technology is composed of packet-based interconnections, where the communication resources are distributed across the network. Therefore, the optimal resource utilization is a crucial consideration for efficient architectural designs. This paper studies the practicality of the Constraint Programming (CP) models for NoC architecture designs that effectively use a regular mesh with wormhole switching and the XY routing. The complexity of the CP models is compared with the earlier Mixed Integer Programming (MIP) models. Practical CP-based mapping and scheduling models are developed and results are reported on the benchmark datasets. Results indicate that mapping and scheduling problems can be solved at near optimality even under relatively shorter run-time limits as compared to those required by the MIP models. [ABSTRACT FROM AUTHOR]

Deep neural networks (DNNs) have been employed to different devices as a popular machine learning algorithm (ML) owing to deploy the Internet of Things (IoT), data mining in cloud computing, and web search engines, which MLs had an impressive effect on IoT's edge level nodes. Deploying DNN-based applications leads to memory access problems, including communication delay, energy efficiency, and bandwidth requirement. We propose a bus scheduling for data placement on distributed local buffers in a deep learning accelerator (DLA). The contributions of this paper include (1) providing a method for data-flow mapping between off-chip DRAM and distributed local buffers, and a flow mapping approach for data transfer between distributed local buffers and processing elements (PEs) (2) employing distributed local buffers in four directions for traffic distribution on a mesh based on memory access mechanism (3) bus scheduling for data placement on distributed local buffers. Simulated experiment based on typical DNN (i.e., AlexNet, VGG-16, and GoogLeNet) workflows demonstrates the effectiveness of the design: (1) the scheduling and mapping methods improve total runtime and bandwidth requirement by approximately 42.29% and 88.95% compared with TPU, respectively. Additionally, (2) our methods reduce total runtime for row-column stationary plus by approximately 99% compared with weight-stationary data-flow in CONV1 and CONV11 of VGG-16, respectively. This work reports the simulation results based on distributing AlexNet, VGG-16, and GoogLeNet's traffics as the popular CNNs and DNNs models, whereas it investigates our method's efficiency for other trained models. [ABSTRACT FROM AUTHOR]

Network-on-chip (NoC) architecture is regarded as a solution for future on-chip interconnects. However, the performance advantages of conventional NoC architectures are limited by the long latency and high power consumption due to multi-hop long-distance communication among processing elements. To solve these limitations, we employed on-chip wireless communication as express links for transferring data so that transfer latency can be reduced. A hybrid NoC architecture utilizing both wired and wireless communication approaches is proposed in this paper. We also devised a deadlock-free routing algorithm that is able to make efficient use of the incorporated wireless links. Moreover, simulated annealing optimization techniques were applied to find optimal locations for wireless routers. Cycle-accurate simulation results showed a significant improvement in transfer latency. Area and power consumption analysis demonstrates the feasibility of our proposed NoC architecture. [ABSTRACT FROM AUTHOR]

Spin transfer torque magnetic random access memory (STT-MRAM) is a promising candidate for next generation memory as it is non-volatile, fast, and has unlimited endurance. Another important aspect of STT-MRAM is that its core component, the nanoscale magnetic tunneling junction (MTJ), is thought to be radiation hard, making it attractive for space and nuclear technology applications. However, studies on the effects of ionizing radiation on the STT-MRAM writing process are lacking for MTJs with perpendicular magnetic anisotropy (pMTJs) required for scalable applications. Particularly, the question of the impact of extreme total ionizing dose on perpendicular magnetic anisotropy, which plays a crucial role on thermal stability and critical writing current, remains open. Here we report measurements of the impact of high doses of gamma and neutron radiation on nanoscale pMTJs used in STT-MRAM. We characterize the tunneling magnetoresistance, the magnetic field switching, and the current-induced switching before and after irradiation. Our results demonstrate that all these key properties of nanoscale MTJs relevant to STT-MRAM applications are robust against ionizing radiation. Additionally, we perform experiments on thermally driven stochastic switching in the gamma ray environment. These results indicate that nanoscale MTJs are promising building blocks for radiation-hard non-von Neumann computing. [ABSTRACT FROM AUTHOR]

Quantum dot cellular automata (QCA) is one of the nano-scale computing paradigms which promises high speed and ultra-low power consumption. Since the one-bit full adder is a fundamental building block of arithmetic circuits, designing an efficient QCA full adder cell is very imperative in this new technology. In this paper, we propose a QCA full adder using a new inverter gate which leads to reduced complexity and area occupation. The proposed layout is simulated by the QCA designer engines. We also provide a performance comparison of our proposed QCA full adder with the previous relevant designs. Furthermore, a detailed analysis of energy dissipation is performed which demonstrates the superiority of the proposed design in terms of the energy efficiency. [ABSTRACT FROM AUTHOR]

This paper investigates the transmission of an injection-locked optical orthogonal frequency-division multiplexing (ILO-OFDM) scheme over an optical fiber. In the ILO-OFDM system, an optically injection-locked semiconductor laser is utilized to directly modulate the OFDM signal on the optical carrier. With a sufficiently large injection strength and a negative shift of the detuning frequency, the modulation sidebands become asymmetric similar to a single sideband modulation (SSB). The SSB spectrum is advantageous for minimizing the chromatic dispersion-induced power variation. Using simulation we show that ILO-OFDM system can be used to compensate for chromatic dispersion in long-haul applications. [ABSTRACT FROM AUTHOR]