A novel deep submicron bulk planar sizing strategy for low energy subthreshold standard cell libraries

Engineering andPhysical Science ResearchCouncil (EPSRC) and Arm Ltd for providing funding in the form of grants and studentshipsThis work investigates bulk planar deep submicron semiconductor physics in an attempt to improve standard cell libraries aimed at operation in the subthreshold regime and in Ultra Wide Dynamic Voltage Scaling schemes. The current state of research in the field is examined, with particular emphasis on how subthreshold physical effects degrade robustness, variability and performance. How prevalent these physical effects are in a commercial 65nm library is then investigated by extensive modeling of a BSIM4.5 compact model. Three distinct sizing strategies emerge, cells of each strategy are laid out and post-layout parasitically extracted models simulated to determine the advantages/disadvantages of each. Full custom ring oscillators are designed and manufactured. Measured results reveal a close correlation with the simulated results, with frequency improvements of up to 2.75X/2.43X obs erved for RVT/LVT devices respectively. The experiment provides the first silicon evidence of the improvement capability of the Inverse Narrow Width Effect over a wide supply voltage range, as well as a mechanism of additional temperature stability in the subthreshold regime. A novel sizing strategy is proposed and pursued to determine whether it is able to produce a superior complex circuit design using a commercial digital synthesis flow. Two 128 bit AES cores are synthesized from the novel sizing strategy and compared against a third AES core synthesized from a state-of-the-art subthreshold standard cell library used by ARM. Results show improvements in energy-per-cycle of up to 27.3% and frequency improvements of up to 10.25X. The novel subthreshold sizing strategy proves superior over a temperature range of 0 °C to 85 °C with a nominal (20 °C) improvement in energy-per-cycle of 24% and frequency improvement of 8.65X. A comparison to prior art is then performed. Valid cases are presented where the proposed sizing strategy would be a candidate to produce superior subthreshold circuits

Symmetrical and asymmetrical outcomes of leader anger expression: a qualitative study of army personnel

Recent studies have highlighted the utility of anger at work, suggesting that anger can have positive outcomes. Using the Dual Threshold Model, we assess the positive and negative consequences of anger expressions at work and focus on the conditions under which expressions of anger crossing the impropriety threshold are perceived as productive or counterproductive by observers or targets of that anger. To explore this phenomenon, we conducted a phenomenological study (n = 20) to probe the lived experiences of followers (as observers and targets) associated with anger expressions by military leaders. The nature of task (e.g. the display rules prescribed for combat situations) emerged as one condition under which the crossing of the impropriety threshold leads to positive outcomes of anger expressions. Our data reveal tensions between emotional display rules and emotional display norms in the military, thereby fostering paradoxical attitudes toward anger expression and its consequences among followers. Within this paradoxical space, anger expressions have both positive (asymmetrical) and negative (symmetrical) consequences. We place our findings in the context of the Dual Threshold Model, discuss the practical implications of our research and offer avenues for future studies

Estimating Dependency Structure as a Hidden Variable

This paper introduces a probability model, the mixture of trees that can account for sparse, dynamically changing dependence relationships. We present a family of efficient algorithms that use EM and the Minimum Spanning Tree algorithm to find the ML and MAP mixture of trees for a variety of priors, including the Dirichlet and the MDL priors. We also show that the single tree classifier acts like an implicit feature selector, thus making the classification performance insensitive to irrelevant attributes. Experimental results demonstrate the excellent performance of the new model both in density estimation and in classification

Experiential Learning in Industrial/Organizational Psychology: A Case Study

Experiential learning is considered a powerful tool for learning in college. Community-based research is one type of experiential learning that has been used to learn research skills in a variety of social science disciplines. The current case study was conducted as an experiential learning research project. A team of six students and a professor from a small Midwestern college conducted community-based research with a large agribusiness company headquartered near the college. The goal of the project was to create an effective employee-selection process for this firm and to provide an effective learning experience for students. This included development of a situational judgment test, cognitive ability testing, and personality assessment. The article focuses on steps taken to organize a community- based research project, the steps required to develop an effective selection process, and an evaluation of the experience from students, the community partners, and faculty

Design and Testing of a Bidirectional Smart Charger Prototype

Rising greenhouse gas emissions, increased fuel costs, and recent technological advances are causing a paradigm shift in the auto-industry away from traditional internal combustion engine vehicles to Electric Vehicles (EVs). Although good for the environment, mass deployment of electric and hybrid electric vehicles has the possibility to cause negative effects to the power grid, such as phase imbalances, voltage deviations, and distribution transformer overloading, since some EVs can potentially draw as high as 19.2 kW in a household from a single-phase outlet. However, if charging is properly controlled and coordinated, EVs have the potential to support the power grid, possibly acting as distributed generation or a storage unit. This thesis aims to address the aforementioned issues by developing a fully-functional “smart” bidirectional EV charger prototype. The term smart refers to the charger’s ability to control the charging and discharging of the battery pack based on the preferences of the car owner, the electricity price at the time of use, battery’s operational constraints, and the distribution system’s requirements at the command of the utility or Local Distribution Company (LDC). Bidirectional refers to power flow, i.e., the charger will employ a design that allows the power to flow from the grid to the battery and vise-versa. The thesis first reviews existing bidirectional charger topologies and smart grid communication technologies. Then, relevant standards, battery technologies, and controller options are discussed; this finally is followed by the charger design process and simulation results to validate the design. Finally, the smart bidirectional charger prototype is presented and tested, to validate and demonstrate its effectiveness in addressing power grid issues

P2_3 Tennis Ball Tunnelling

This paper aims to calculate the probability of a tennis ball quantum tunnelling through a tennis racket. This is done by treating the tennis ball as a single particle, and making the potential barrier equal to the energy required to break the strings classically. The probability of tunnelling through a racket is found to be 3.6exp(-2.9x10^31). This very low probability matched with what would be expected. The paper also briefly discusses the problem of decoherence when applying quantum mechanics to macroscopic systems

P2_5 Bouncing Back

This paper aims to calculate the probability of a person being reflected back from a cliffs edge whilst try to run off of it. This is by treating the cliff as a negative potential step, and the person as a point of mass. The probability of reflection is found to be = which although extremely small, is non-zero. The paper also discusses the limits of the model presented when considering decoherence

P2_7 Not So Incy Wincy

This paper takes the abilities of spider silk to the extreme by examining how thick a single strand would have to be in order to stop a commercial airliner mid-flight. We found that a 50m long strand with a diameter of 12.57cm would be able to bring the aircraft to rest without exceeding the limit of elasticity