Power mad [low-power design

Power reduction is nowadays becoming the first consideration in VLSI design. Low power is one of major concerns in deeply scaled CMOS technologies. There have been many methods in very wide rang to achieve this objective. And the Register-Transfer level (RTL) has become the most effective stage in low power VLSI design, according to the significant power optimization impact and accurate power estimation. In this paper, some respective low power design techniques at RTL are re-investigated at tsmc 45 nanometer CMOS technology. Clock gating (CG) is one of the most widely used and effective technique in RTL low power design. Without the enable signal, bus-specific clock gating (BSC) and threshold-based clock gating (TCG) are considered. Also an improved active-driven optimized bus-specific clock gating (OBSC) is proposed in our laboratory. When the enable signal is taken into account, this paper explains local-explicit clock gating (LECG), enhanced clock gating (ECG), waste-toggle-rate-based (WTR) clock gating and the single comparator-based clock gating (SCCG) techniques. Operand isolation is another useful design technique for reducing the power consumption by blocking some redundant operations. Memory splitting is an effective design solution for low power design as well. These techniques have been experimented by using tsmc 45nm technology library and the proposed low-power RTL techniques are evaluated at gate level with logic synthesis results.

Two versions of a distributed-memory model, one for associative information and one for serial-order information, leave open the question of whether there are two different modes of operation or only one. An analysis of these two versions showed that differential predictions emerge when one considers the role of item information. To test these predictions, a standard item-recognition task (Sternberg, 1966) was embedded in a paired-associate probe-recognition task, a serial-order probe-recognition task, or both. The item-recognition serial-position curves were quite different in the paired-associate and the serial-order conditions, and followed the paired-associate condition when the two were combined. In general, the results were consistent with the predictions of the distributed-memory models, and supported the idea of different modes of operation rather than a single common mode of operation.

In the IoT for multi-sensor node application [1], there are demanded both high-performance for computation in an active mode, and an ultra-low standby power in a sleep mode for longtime buttery life in the energy efficient system. Ultra-low standby MCU with embedded NVM using 90 nm CMOS technology is also reported [2], but its SRAM cache is not sufficient for applying imaging processing which requires large memory capacity with imaging sensors in edge computing. Embedded SRAMs can be achieved fast read/write access within a few nanoseconds, but consume standby leakage power for data retention, being dominant power in the sleep mode. To reduce the standby leakage power of embedded SRAMs, the source bias design technique with power-gating is introduced on a bulk CMOS device [3]. In the resume standby (RS) mode, the VSS source bias control for SRAM array is demonstrated as an effective SRAM leakage power reduction. Besides, once the large SRAM array are into the resume standby mode, it takes long time to wake-up again. It is not applicable for high-speed CPU operation. Then, a fast resume standby mode (FRS) for cache memories is proposed to wake-up as much as fast. In that FRS mode, the power supply for SRAM peripheral is cutoff but SRAM array is keeping with a VDD supply. Each standby mode and its circuit diagram are summarized in Fig. 1. Meanwhile, dopant-less channel fully-depleted (FD) silicon-on-insulator (SOI) device is proposed [4]–[6] to improve the performance, power, and area (PPA) of embedded SRAMs. FD-SOI enables to control the back-bias (BB) dynamically under the buried-oxide (BOX) to reduce leakage current and/or to improve performance by applying reverse or forward bias, respectively. Fig. 2 presents the block diagram of BB control scheme for voltage scaling in IoT application with FD-SOI structure [7]–[9]. BBs for NMOS (VBN) and PMOS (VBP) can be applied individually by VBB generator (VBB Gen.) circuit. Four operation modes for smart IoT applications are considered. High-performance, normal, low-power operating modes are introduced, along with the required loads in the system. The sleep mode with SRAM data retention for long-term waiting in the sensor nodes is also proposed. Each supply voltage and BB is also shown in Fig. 2. The comparison of embedded SRAM leakage power is shown in Fig. 3.

In-ear and earmuff-type electronic protection devices are rapidly being introduced into the marketplace and deployed in noisy industrial workplaces and military settings. In these environments, workers must be sufficiently protected from noise while being able to maintain good communication abilities and situational awareness. Features such as level-dependent attenuation or amplification, noise reduction, and remote communication capabilities are commonly found in advanced devices. The benefits of these features depend on their complex interaction with the signal and noise characteristics, the hearing status and language proficiency of the workers, and the nature of the auditory task. Furthermore, advanced devices often have different modes of operation and several user-adjustable control settings. In this paper, the interaction between the gain control setting and the degree of hearing loss is investigated for two level-dependent devices in a speech recognition task in noise. At all gain settings, the level-dependent mode of the devices provided better speech recognition that passive attenuation for all groups of subjects, and performance often exceeded unprotected listening.

The brain circuitry of attention

The problem of the development of modern bearings (magnetic, gas, etc.) for high-speed machines with a wide range of capacities (from tens of kilowatts to megawatts) and rotational speeds (from 6000 to 60000 rpm) used in oil and gas production, robotics, space technology, and mini gas-turbine power plants is considered. The distribution of forces applied to the rotor shaft in different modes of operation is investigated including the case of shaft eccentricity. In operation, the eccentricity should not exceed 5%. A computer system is designed on the basis of the numerical method for field (2D) computation in the active part of the machine. The distribution of forces is analyzed taking into account the saturation of the magnetic circuit of the machine and the harmonic content of the mutual magnetic flux (flux in the gap). When calculating these forces in the no-load mode of operation, it was assumed that, in machines with permanent magnets, the mutual magnetic flux on the rotor is about 10–15% higher than under the rated load because of the demagnetization effect of the armature reaction. The mutual magnetic flux was specified depending on the type of rotor magnets. The computer system takes into account the relative position of the rotor poles relative to the stator field reaction under load (load angle Θ). It is also taken into account that, during use, the resulting mutual magnetic flux is distorted (compared to the no-load mode). As a result, a number of additional high harmonics appear in the gap, which affect the forces applied to the rotor shaft. Load angle Θ is calculated using graphical options of the simulation package by the iteration method. An algorithm for the implementation of this method is described. The distribution of the radial forces along the rotor shaft surface (differential parameter) and the total radial attraction force applied to the rotor shaft (integral parameter) are calculated for different values of eccentricity and different modes of operation of high-speed machines.

Molecular characterization of the microbial community structure in two activated sludge systems for the advanced treatment of domestic effluents

The paper is focused on simulating the discharge of Li-Ion batteries using series and parallel cells in different modes of operation. The simulations are realized using Matlab/Simulink. Two cases are analyzed for the system under test: constant discharge current and a variable discharge current. In these cases the batteries were considered 100% or partially charged. For a series cell we used four batteries and for the parallel connection we used three series cells. The simulated waveforms for the state of charge (SoC) and the output voltage of batteries are presented for the analyzed cases.

With the growing number of physically disabled person in the present age, the usage of wheelchair has become unprecedented. Electric autonomous smart wheelchairs have emerged as the go to caring module for the disabled people. The proposed electric health monitoring smart wheelchair system is intended to be an all-in-one electric wheelchair that surpasses its previous predecessors. It allows the user to independently move around both indoor and outdoor using 3 different mode of operation – gesture control for controlling via neck movement, Joystick control & voice command module. It is incorporated with ultrasonic sonar edge detection module & obstacles detection both front and back to ensure safety of the patient. A variety of sensors such as heart rate sensor, PIR sensor, load cell, temperature & humidity detection are attached to keep monitoring the patient while he/she is sitting on the wheelchair. In the event of any accident or anomaly in the health monitoring data, the system will notify the relative and affiliated medical institution via SMS combined with GPS location. The proposed wheelchair system also incorporates retractable solar panel to charge the battery while operating outdoors. The proposed prototype model has been tested in a local area and the practical simulation data gained is promising. As a whole, the proposed prototype has a great deal to offer to the disabled population.

A Monod kinetic model, logistic equation model, and statistical regression model were developed for a Chinese hamster ovary cell bioprocess operated under three different modes of operation (batch, bolus fed-batch, and continuous fed-batch) and grown on two different bioreactor scales (3 L bench-top and 15 L pilot-scale). The Monod kinetic model was developed for all modes of operation under study and predicted cell density, glucose glutamine, lactate, and ammonia concentrations well for the bioprocess. However, it was computationally demanding due to the large number of parameters necessary to produce a good model fit. The transferability of the Monod kinetic model structure and parameter set across bioreactor scales and modes of operation was investigated and a parameter sensitivity analysis performed. The experimentally determined parameters had the greatest influence on model performance. They changed with scale and mode of operation, but were easily calculated. The remaining parameters, which were fitted using a differential evolutionary algorithm, were not as crucial. Logistic equation and statistical regression models were investigated as alternatives to the Monod kinetic model. They were less computationally intensive to develop due to the absence of a large parameter set. However, modeling of the nutrient and metabolite concentrations proved to be troublesome due to the logistic equation model structure and the inability of both models to incorporate a feed. The complexity, computational load, and effort required for model development has to be balanced with the necessary level of model sophistication when choosing which model type to develop for a particular application.

Recently, the problem of designing a carbon, hydrogen, and oxygen symbiosis network (CHOSYN) has been introduced to enable the systematic integration of multiple plants and to determine chemical conversion, separation, and allocation schemes through a multiscale atomic targeting approach. The previous contributions in designing CHOSYNs assumed a single mode of operation for all participating plants. Since some plants may have seasonable variabilities, multiple modes of operation may be necessary. Each mode of operation is characterized by different flow rates and compositions of the integrated streams. The objective of this work is to develop a multiperiod approach to design a CHOSYN by considering multiple modes of operation throughout the year. A multiscale targeting approach is proposed to determine the optimal type and size of the common infrastructure for all participating plants under different modes of operation. A case study involving five industrial plants and two modes of operation is presented ...

This paper focuses on the super/subsynchronous operation of the doubly fed induction generator (DFIG) system. The impact of a damping controller on the different modes of operation for the DFIG-based wind generation system is investigated. The coordinated tuning of the damping controller to enhance the damping of the oscillatory modes using bacteria foraging technique is presented. The results from eigenvalue analysis are presented to elucidate the effectiveness of the tuned damping controller in the DFIG system. The robustness issue of the damping controller is also investigated.

The article first proposed an approach to improving the accuracy of quantitative assessment of reliability indicators of radio-electronic means with a variable structure, operating in different modes of operation using separate sets of elements in each of them. In the well-known works, this circumstance is not taken into account and there liability indicators of the product are estimated under the assumption that all elements operate simultaneously, which leads to a decrease in the calculated value of mean time to failure. The problem is solved by the introduction of the utilization rate of each structural element of the product in all possible modes of operation. An example of using the obtained results for the quantitative assessment of the time to failure of a radio station is given, and the effect of clarifying the calculations is shown.Reliability of radio-electronic means is quantitatively evaluated by indicators, the main ones being the time between products failure and the average time of its recovery. They define a comprehensive measure of reliability - availability. Reducing the calculated value of time between failures requires, to ensure its desired value, the use of more reliable components, which leads to an increase in the value of the product as a whole.The article for the first time obtained a mathematical model for assessing reliability indicators, taking into account the product operation time in each of the possible modes, and when calculating the maintainability index, metrological reliability of measuring equipment tools that are used in the process of diagnostics during radio repair is taken into account.The proposed model for estimating the values of reliability indicators of objects with variable structure is advisable to use at the design stage of modern radio electronic equipment. The effect of its implementation is to provide the specified values of reliability indicators of multi-mode electronic means at their minimum cost.

This paper surveys the state-of-the-art in operation-based property checking and describes how this technique can be used to conceptualize on a design at the Register-Transfer-Level (RTL). The paper argues that this technique can contribute to closing the semantic gap between system level design descriptions and the RTL and, thus, opens new possibilities for solving the power closure problem. The semantics of the high-level model are defined in terms of properties to be proven on the concrete RTL. The paper surveys a methodology to create sound abstractions and elaborates their possible role in a power-aware design flow. Specifically, it is demonstrated that the availability of a formal specification at an abstract level can be exploited for energy estimations at the system level as well as for deriving power optimizations at the RTL. First experimental results will be shown that demonstrate this optimization potential and confirm the correlation between energy consumption and operations which are the basic building blocks of the proposed abstract models.

The paper examined the problem of modeling and design of software computer systems. The article briefly describes the content aspects of the various stages of the implementation of software complexes and systems. The methodology of research and analysis of systems, which uses the method of computer simulation modeling, is given. The aim of the work is to create a new universal approach to the design and implementation of software systems of various levels of complexity. During the study, the following general scientific methods were used: system analysis, synthesis, formalization, modeling, decomposition, structuring, description, comparison. The materials used in the study were: computers and software development tools. As a result of the study proposed a universal agent-module approach to the design and implementation of software systems based on simulation agent-based modeling. The study presents the processes of modeling and designing software systems, their stages, and the possibility of their integration within the described approach. Examples of formal model and structure of the software system under design based on the agent-module approach are presented. The proposed approach can be used in the process of software development at the initial stages related to modeling and designing of software systems. Integration of modeling and design stages in the proposed approach will significantly reduce software development time and simplify the design process by making it clearer and more formalized. Materials of the article are of scientific and practical value for a wide range of specialists interested in system analysis, modeling, design and implementation of software systems.