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This paper discusses heterogeneous Network-on-Chip (NoC) design from a Constraint Programming (CP) perspective and extends the formulation to solving Voltage-Frequency Island (VFI) problem. In general, VFI is a superior design alternative in terms of thermal constraints, power consumption as well as performance considerations. Given a Communication Task Graph (CTG) and subsequent task assignments for cores, cores are allocated to the best possible places on the chip in the first stage to minimize the overall communication cost among cores. We then solve the application scheduling problem to determine the optimum core types from a list of technological alternatives and to minimize the makespan. Moreover, an elegant CP model is proposed to solve VFI problem by mapping and grouping cores at the same time with scheduling the computation tasks as a limited capacity resource allocation model. The paper reports results based on real benchmark datasets from the literature. [ABSTRACT FROM AUTHOR]

Multiple memory stacks can be integrated with a processor chip in the silicon interposer technology ("2.5D" stacking). In 2.5D architecture, there are two different network layers for both coherence and memory traffic. The CPU layer is used for coherence Core-to-Core traffic, while the interposer layer is associated with Core-to-Memory blocks traffic regularly. A load balancing strategy balances the traffics on the two network layers and optimizes the resources utilization. In the aforementioned strategy, after detecting congestion in the CPU layer, packets can be moved to the interposer one. It can be concluded that this transferring encounters the bottleneck of the edge portion that is connected to memory blocks. In this paper, we propose a Controlled Load Balancing Mechanism (CLBM) which efficiently controls bottleneck in load balancing methods. As a result, the CLBM selects an appropriate network based on the destination address without comparing latencies of two networks. Moreover, a multicast fault-tolerant ring is introduced to propagate network congestion information. The experimental results showed that, as compared with the absence of load balancing method and traditional load balancing strategy, our CLBM strategy achieves 37.82% and 17.22% average latency improvements and 22.19% and 8.55% average total power with minor overhead. [ABSTRACT FROM AUTHOR]

Highlights • BC-NoC is an efficient method to reduce network packet latency. • Proposed RIP BC-NoC partitioning method enhances workload consolidation density. • Task communication minimally uses other application resources. • Application tasks can be mapped close to each other in a straight path. • Increased consolidation density & reduced latency improve performance parameters. Abstract The network on a chip (NoC) is considered as the main shared communication resource to avoid compromise the system performance. A strict isolation strategy is employed in the NoC to avoid performance degradation; however, this strategy is accompanied by a low consolidation density or a complex routing mechanism, which leads to considerable latency and high hardware costs. We propose the row irregular partitioning (RIP) method, which results in a high consolidation density compared to regularity-oriented topology. We additionally propose a congestion awareness (CA) mapping scheme in which mapping is performed based on congestion control on a route in a bypass-channel-based NoC (BC-NoC). Furthermore, mapping methods, such as straight path (SP) and straight path and congestion awareness (SP&CA), are recommended to exploit the communication platform properties of BC-NoC. The experimental results show that the average delay in the SP mapping method is improved compared with SP&CA and CA. [ABSTRACT FROM AUTHOR]

Three dimensional Networks-on-Chip (3D NoCs) have evolved as an ideal solution to the communication demands and complexity of future high density many core architectures. However, the design practicality of 3D NoCs faces several challenges such as thermal issues, high power consumption and area overhead of 3D routers as well as high complexity and cost of vertical link implementation. To mitigate the performance and manufacturing cost of 3D NoCs, inhomogeneous architectures have emerged to combine 2D and 3D routers in 3D NoCs producing lower area and energy consumption while maintaining the performance of homogeneous 3D NoCs. Due to the limited number of vertical links, application mapping on inhomogeneous 3D NoCs can be complex. However, application mapping has a great impact on the performance and energy consumption of NoCs. This paper presents an energy and performance aware application mapping algorithm for inhomogeneous 3D NoCs. The algorithm has been evaluated with various realistic traffic patterns and compared with existing mapping algorithms. Experimental results show NoCs mapped with the proposed algorithm have lower energy consumption and significant reduction in packet delays compared to the existing algorithms and comparable average packet latency with Branch-and-Bound. [ABSTRACT FROM AUTHOR]

Efficient on-chip communication is necessary for exploiting enormous computing power available on a many-core chip. Routing algorithms play a major role for the communication quality and performance of the on-chip interconnection networks. This paper proposes TagNoC, as an on-chip network router architecture with novel hybrid routing approach which reduces latency and power consumption at a fixed cost based on information redundancy. TagNoC is a hybrid routing approach which combines the source and distributed routing methods together. While eliminating packet routing in each router, TagNoC determines the forwarding output port in parallel with input buffering. For a marginal cost increase in header size, as compared to distributed routing techniques, routing latency can be hidden while eliminating power consuming portion of the routing, increasing router throughput and decreasing latency. The proposed TagNoC router is compared to baseline router with distributed routing implementation on a 16-node CMP mesh. Physical implementation of all routers is modeled using synthesized RTL, detailed area analysis, and accurate channel models. Performance evaluation is also carried out utilizing RTL simulation and detailed power analysis on both synthetic and application traffic is performed using post-synthesis gate-level simulation. The simulation results illustrate that TagNoC outperforms as compared to baseline distributed architecture and other source routing methods in terms of power, latency, and throughput. [ABSTRACT FROM AUTHOR]

We propose a lightweight scheme where the formation of a data block is changed in such a way that it can tolerate soft errors significantly better than the baseline. The key insight behind our work is that CNN weights are normalized between -1 and 1 after each convolutional layer, and this leaves one bit unused in half-precision floating-point representation. By taking advantage of the unused bit, we create a backup for the most significant bit to protect it against the soft errors. Also, considering the fact that in MLC STT-RAMs the cost of memory operations (read and write), and reliability of a cell are content-dependent (some patterns take larger current and longer time, while they are more susceptible to soft error), we rearrange the data block to minimize the number of costly bit patterns. Combining these two techniques provides the same level of accuracy compared to an error-free baseline while improving the read and write energy by 9% and 6%, respectively. [ABSTRACT FROM AUTHOR]

Silent Data Corruptions (SDCs), those errors that escape detection methods, are critical for system designers because they may result in systems failures. In order to catch SDCs, mechanisms should focus on the behavioural aspects of errors in addition to their physical location or error patterns. Therefore, protection codes like parity, hamming, and the Reed-Solomon code, which heavily depend on the physical location of data bits, are not enough in processors for detection of computing errors. Using characterizing data behaviour during program executions, we have observed value locality in results of destination register for each instruction binary code (instruction opcode and operand codes). This locality exists not only in the results of each instruction, but also in the results of instructions at different memory locations having the same binary code. As a result, an architecture called Instruction Result History Table (IRHT) is presented, which is indexed by the instruction binary code. In the IRHT, a history of values produced by the same instruction binary codes are stored in and utilized during each instruction execution cycle. Any mismatch between the stored values in the IRHT and those generated by current execution, indicates an SDC syndrome. To confirm having SDCs with a high level of confidence, a second execution of the current instruction is issued. A duplication of the execution confirms whether SDC occurred. In the case of SDCs, a third instruction execution with the help of a majority voting frees the system of SDC. Several extensive simulations showed that, up to 83.54% of SDCs are detectable with the help of this locality. Moreover, with the small hardware, IRHT, i.e., 16 kB size, 80.66% of SDCs can be detected on average. Note that the presented method can detect those errors that escape conventional detection mechanisms. So, it can be utilized in conjunction with other conventional methods. [ABSTRACT FROM AUTHOR]

The balanced ternary representation allows for significant performance improvement for ternary systems. Immaturity of the semiconductor industry in providing an applicable device for ternary infrastructures during the past decades is an enormous obstacle to actualize the ternary circuit realization. Among the promising devices for this purpose, carbon nanotube field effect transistor (CNFET) is qualified with outstanding characteristics which make it suitable for implementing the ternary logic functions. In this paper, for the first time, we present and evaluate the basic ternary arithmetic circuits in balanced representation based on the CNFET technology. Experimental evaluation of reviewed designs in both balanced and unbalanced representation indicates the superiority of the balanced representation in the design of ternary arithmetic blocks. [ABSTRACT FROM AUTHOR]

Backgrounds: Nowadays developing smart and fast services for patients and transforming hospitals to modern hospitals is considered a necessity. Living in the world inundated with information systems, designing services based on information technology entails a suitable architecture framework.Objectives: This paper aims to present a localized enterprise architecture framework for the Iranian university hospital.Methods and Results: Using two dimensions of implementation and having appropriate characteristics, the best 17 enterprises frameworks were chosen. As part of this effort, five criteria were selected according to experts' inputs. According to these criteria, five frameworks which had the highest rank were chosen. Then 44 general characteristics were extracted from the existing 17 frameworks after careful studying. Then a questionnaire was written accordingly to distinguish the necessity of those characteristics using expert's opinions and Delphi method. The result showed eight important criteria. In the next step, using AHP method, TOGAF was chosen regarding having appropriate characteristics and the ability to be implemented among reference formats. In the next step, enterprise architecture framework was designed by TOGAF in a conceptual model and its layers. For determining architecture framework parts, a questionnaire with 145 questions was written based on literature review and expert's opinions. The results showed during localization of TOGAF for Iran, 111 of 145 parts were chosen and certified to be used in the hospital.Conclusion: The results showed that TOGAF could be suitable for use in the hospital. So, a localized Hospital Enterprise Architecture Modelling is developed by customizing TOGAF for an Iranian hospital at eight levels and 11 parts. This new model could be used to be performed in other Iranian hospitals. [ABSTRACT FROM AUTHOR]

This paper presents two new ternary operators which can be used in different scrambling crypto algorithms. The employment of the proposed operators ( ScramOp1 and ScramOp2 ) leads to reduction in the number of decoding steps, equivalent to only one operation per digit for the receiver side. These operators are presented for the first time in ternary logic. There are some other ternary operators such as SUM , which are specifically suitable for computer arithmetic but they lack desirable efficiency for cryptographic applications. The transistor-level designs of the operators are simulated by using Synopsys HSPICE with 32 nm bulk-CMOS technology. Simulation results demonstrate that ScramOp1 and ScramOp2 achieve significant saving in energy consumption (2.11% and 12.14%) in comparison with SUM . Additionally, ScramOp2 requires only 52 transistors while 58 and 60 transistors are needed to implement ScramOp1 and SUM , respectively. [ABSTRACT FROM AUTHOR]

Nanotechnologies, notably quantum-dot cellular automata, have achieved world-wide attentions for their prominent features as compared to the conventional CMOS circuitry. Quantum-dot cellular automata, particularly owning to its considerable reduction in size, energy consumption and latency of circuits, is considered as a potential alternative for the CMOS technology. Considering the manufacturing aspects, in this paper, a method is proposed for designing efficient quantum-dot cellular automata circuits. We inspect an alternative approach for streamlined design of quantum-dot cellular automata circuits such that the required external fixed inputs are substantially reduced. In order to demonstrate the efficiency of the proposed method, the widely used multiplexer, XOR and party generator circuits are considered as case studies. All of the proposed circuits are simulated and verified using QCADesigner which is a valid and popular simulation tool. Comparisons indicate that the proposed method considerably reduces the number of external fixed inputs which simplifies the overall circuit implementation and fabrication. [ABSTRACT FROM AUTHOR]

Recently, Multiple Valued Logic (MVL) has attracted attention, because it reduces the area and complexity of circuits when compared to binary logic. Carbon nanotube field effect transistors (CNFET) are a good candidate for implementing MVL logic circuits, since determining the threshold voltage value of CNFET is easily achievable by changing the diameter of the nanotubes which are placed under the transistor gate. In this paper, quaternary CNFET based 4–2 and 5–2 compressor cells have been proposed. The proposed cell designs were investigated using HSPICE simulator with the standard 32 nm CNFET technology under different operational conditions such as different temperatures, different load capacitances, and different supply voltages. Also the sensitivity to process variations and noise immunity of the proposed designs have been investigated. The proposed quaternary logic designs reduce the delay of the multi operand addition of arithmetic circuits by eliminating the carry propagation overhead. [ABSTRACT FROM AUTHOR]

This paper presents a novel method for design and implementation of three dimensional (3D) two-layer devices with 1/0 logic values. This method uses carbon nanotube (CNT) technology as well as the molecular quantum cellular automata (MQCA) technology on a graphene substrate. The most significant characteristic of the proposed design, which makes the design unique, is the capability of generating functions in 3D; the proposed method would allow implementation of the designs in a single layer which significantly impacts on reducing the chip area and also greatly facilitates the overall synthesis of the design including placement, routing and reducing the critical path length. [ABSTRACT FROM AUTHOR]

This paper presents a new ternary operator for cyclic redundancy check in ternary logic with high hardware efficiency. It shows the essential properties of a ternary operator for calculating CRC. Gate-level implementation of CRC-16 is exemplified and comprehensively explained in this paper. Transistor-level realizations of the new and the previous operators are also given in full detail. This paper demonstrates that the employment of the proposed operator reduces hardware components such as the elimination of one entire operator in both transmitter and receiver sides in comparison with ternary SUM . In addition, simulation results by HSPICE and 32 nm CNTFET technology shows about 20.6% energy reduction for one of the implementation methods of the proposed operator with respect to the previously presented one ( CCW CYCLE ). Furthermore, five fewer transistors are needed to design the proposed operator in contrast with both operators SUM and CCW . [ABSTRACT FROM AUTHOR]

In this paper energy-efficient multiple valued logic (MVL) circuits based on carbon nanotube field effect transistor (CNTFET) are proposed. These circuits are designed based on the unique properties of CNTFETs, such as having same mobility for electrons and holes and also capability of adopting desirable threshold voltage by adjusting the CNTs diameters. The proposed designs have high driving capability, larger noise margins and higher robustness as compared to the previous CNTFET-based designs. The proposed quaternary circuits are examined using HSPICE simulator with the standard CNTFET technology. Simulation results demonstrate more energy-efficient and robust operation of the proposed designs, as compared to the other state-of-the-art CNTFET-based MVL circuits, recently presented in the literature. According to the simulation results the proposed STNOT, STNAND and STNOR circuits have on average 82%, 76% and 45% lower power-delay product (PDP), respectively as compared to their state-of-the-art counterparts. In addition, the proposed QNOT, QNAND and QNOR circuits have the average PDP improvements of 79%, 42% and 61%, respectively, as compared the other recently presented CNTFET-based quaternary designs. [ABSTRACT FROM AUTHOR]

Quantum-dot cellular automata (QCA) exhibits a new paradigm at nanoscale for possible substitution of conventional CMOS technology. Most of the research works in QCA domain have completely ignored the significance of energy consumption constraint in designing circuits. In this study a low complexity and energy-efficient QCA T flip–flip as well as high-performance single-layer synchronous counters are proposed. By cascading the proposed T flip-flop and a suitable level converter, a QCA-compatible structure for falling edge triggered T flip-flop is achieved. This circuit functions as the chief element for constructing synchronous counters. QCADesigner and QCAPro tools are used for evaluating the functionality and calculating dissipated energy of the circuits, respectively. Results indicate the superiority of the proposed circuits in terms of complexity, latency and energy consumption as compared to their state-of-the-art counterparts. The proposed T flip-flop demonstrates 18% leakage energy improvement besides the considerable value of 56% switching energy improvement in 0.5Ek tunneling energy level as compared to the best ones. It is worth mentioning that 41%, 44% and 45% optimizations in the number of cells in addition to 15%, 25% and 33% optimizations in the area are achieved for the proposed mod 4, mod 8 and mod 16 counters, respectively, in comparison with the best previous results. [ABSTRACT FROM AUTHOR]

• A digital fuzzy approach for image edge detection is proposed. • This method employs simple fuzzy rules for digital image edge detection. • Simple logic gates based on carbon nanotube transistor are used for implementation. • Delay and power are significantly reduced while a reasonable accuracy is provided. This study presents a novel digital fuzzy approach for image edge detection based on carbon nanotube field effect transistor (CNTFET). The proposed design employs a simple fuzzy rule for digital image edge detection. To investigate the functionality and performance of the proposed fuzzy approach, our results are compared with the MATLAB edge detection operators such as Sobel, Canny, and Prewitt. Based on the simulation results, we demonstrate that the proposed fuzzy approach can be implemented through nanoscale logic gates and provide a reasonable accuracy. The core element of the proposed fuzzy system, implemented with CNTFETs, occupies 0.22 µm2 layout area and consumes 535 nW power consumption. Our results also emphasize the benefits of the Gate-All-Around (GAA) CNTFETs as a potential candidate for nanoscale digital fuzzy image processing applications. [ABSTRACT FROM AUTHOR]

This paper presents a novel fully programmable membership function generator (MFG) based on carbon nanotube field effect transistors (CNTFETs). The proposed CNTFET-based MFG has full control over the output characteristics such as height, and position independently. The proposed design can produce four different membership functions only by calibrating the external control bias voltages. Moreover, two peripheral transmission gates are utilized to provide controllability over the slope of the generated membership functions in a wide range. The primary advantage of the proposed MFG compared to its counterparts is the ability to control the slope of the resulted membership functions entirely and separately using only two external bias voltages without the need for changing the device physical dimensions. The simulation results demonstrate that the proposed design improves the power, delay, and layout area, on average by, 72%, 55%, and 33% as compared to the previous designs. Furthermore, the proposed MFG shows only 2.13% RMS error, and 5.65% maximum absolute error for the generated Gaussian trapezoidal membership function as compared to the ideal form. Our results certify that the proposed CNTFET-based MFG has the potential to be used as a promising platform for fuzzy inference systems in deep nanoscale technology nodes. [ABSTRACT FROM AUTHOR]