Parameter adaptation for generalized multiframe tasks: schedulability analysis,case study,and applications to self-suspending tasks

The generalized multiframe task model (GMF) extends the sporadic task model and multiframe task model. Each frame in the GMF model contains an execution time, a relative deadline, and a minimum inter-arrival time. These parameters are fixed after task specification time in the GMF model. However, multimedia and adaptive control systems may be overloaded and no longer stabilized when the task parameters in such systems are not flexible. In order to address this problem, deadlines and periods of frames may change to alleviate temporal overload, e.g., in the parameter adaptation and elastic scheduling model. In this paper, we propose a new model GMF-PA (the GMF model with parameter adaptation). This model allows task parameters to be flexible in arbitrary-deadline systems. A necessary schedulability test based on mixed-integer linear programming is given to check the schedulability under EDF scheduling and optimally assign frame deadlines and periods at the same time. We also prove that the test is a sufficient and necessary schedulability test when frame deadlines and periods must be integers. An approximation algorithm is also deployed to reduce computational running time and indicates a sufficient schedulability test in general. The speed-up factor of our approximation algorithm is \(1+\epsilon \) where \(\epsilon \) can be arbitrarily small, with respect to the exact schedulability test of GMF-PA tasks under EDF. We also apply the GMF model to self-suspending tasks. By extending recent work on scheduling self-suspending tasks, we remove the assumption that frame deadlines are equally assigned in self-suspending tasks, and the system is extended from constrained-deadline systems to arbitrary-deadline systems. We have done extensive experiments to show that the schedulability ratio is improved using our techniques in our GMF-PA model.     

Recyclable,Flexible, Low‐Power Oxide Electronics

The ability to process and dimensionally scale field‐effect transistors with and on paper and to integrate them as a core component for low‐power‐consumption analog and digital circuits is demonstrated. Low‐temperature‐processed p‐ and n‐channel integrated oxide thin‐film transistors in the complementary metal oxide semiconductor (CMOS) inverter architecture are seamlessly layered on mechanically flexible, low‐cost, recyclable paper substrates. The possibility of building these circuits using low‐temperature processes opens the door to new applications ranging from smart labels and sensors on clothing and packaging to electronic displays printed on paper pages for use in newspapers, magazines, books, signs, and advertising billboards. Because the CMOS circuits reported constitute fundamental building blocks for analog and digital electronics, this development creates the potential to have flexible form factor computers seamlessly layered onto paper. The holistic approach of merging low‐power circuitry with a recyclable substrate is an important step towards greener electronics.     

Iron Mobilization from Ferritin in Yeast Cell Lysate and Physiological Implications

Most in vitro iron mobilization studies from ferritin have been performed in aqueous buffered solutions using a variety of reducing substances. The kinetics of iron mobilization from ferritin in a medium that resembles the complex milieu of cells could dramatically differ from those in aqueous solutions, and to our knowledge, no such studies have been performed. Here, we have studied the kinetics of iron release from ferritin in fresh yeast cell lysates and examined the effect of cellular metabolites on this process. Our results show that iron release from ferritin in buffer is extremely slow compared to cell lysate under identical experimental conditions, suggesting that certain cellular metabolites present in yeast cell lysate facilitate the reductive release of ferric iron from the ferritin core. Using filtration membranes with different molecular weight cut-offs (3, 10, 30, 50, and 100 kDa), we demonstrate that a cellular component >50 kDa is implicated in the reductive release of iron. When the cell lysate was washed three times with buffer, or when NADPH was omitted from the solution, a dramatic decrease in iron mobilization rates was observed. The addition of physiological concentrations of free flavins, such as FMN, FAD, and riboflavin showed about a two-fold increase in the amount of released iron. Notably, all iron release kinetics occurred while the solution oxygen level was still high. Altogether, our results indicate that in addition to ferritin proteolysis, there exists an auxiliary iron reductive mechanism that involves long-range electron transfer reactions facilitated by the ferritin shell. The physiological implications of such iron reductive mechanisms are discussed.     

The impact of childhood symptoms of conduct disorder on driver aggression in adulthood

Background

Despite limited empirical investigation, existing scientific literature suggests that individuals with a history or current diagnosis of conduct disorder (CD) may be more likely to demonstrate reckless and aggressive driving. Much of the limited research in this field examines the impact of childhood CD on driver behaviour and collision risk in young adults. Few if any, studies assess the impact of this disorder on driver behaviour beyond age 21 years. The current research is a population-based study of the impact of CD symptoms during childhood on the risk of engaging in driver aggression during adulthood.

Methods

Data are based on telephone interviews with 5230 respondents who reported having driven in the past year. Data are derived from the 2011–2013 cycles of the CAMH Monitor, an ongoing cross-sectional survey of adults in Ontario, Canada aged 18 years and older. A binary logistic regression analysis of self-reported driver aggression in the previous 12 months was conducted, consisting of measures of demographic characteristics, driving exposure, problem substance use, alcohol- and drug-impaired driving, symptoms of attention deficit hyperactivity disorder, and childhood (before age 15) symptoms of CD.

Results

When entered with demographic characteristics, driving exposure, and other potential confounders, childhood symptoms of CD increased the odds of reporting driver aggression more than two-fold (adjusted OR = 2.12). Exploratory analyses of the interaction between childhood symptoms of CD and age was not a significant predictor of driver aggression.

Conclusions

Results suggest that symptoms of CD during childhood are associated with significantly increased odds of self-reported driver aggression during adulthood. Limitations and future directions of the research are discussed.     

The School as an Instrument in Planning

The school today plays a peculiarly dynamic role in neighborhood change, for its quality-real or as perceived by parents-strongly affects the decisions of upper-income families as to where to live. If the school reflects the changing social composition of its immediate neighborhood, it tends to speed up the transition from upper-income to lower-income occupancy and to encourage social homogeneity and segregation. If it maintains special standards and a special approach toward education, independent of changes in the population of the surrounding area, it serves as a brake on population change and tends to encourage heterogeneous neighborhoods. It is suggested this principle may help in achieving stable and heterogeneous neighborhoods.     

Immunoproteasome β5i‐Selective Dipeptidomimetic Inhibitors

N,C‐capped dipeptides belong to a class of noncovalent proteasome inhibitors. Herein we report that the insertion of a β‐amino acid into N,C‐capped dipeptides markedly decreases their inhibitory potency against human constitutive proteasome β5c, while maintaining potent inhibitory activity against human immunoproteasome β5i, thereby achieving thousands‐fold selectivity for β5i over β5c. Structure–activity relationship studies revealed that β5c does not tolerate the β‐amino acid based dipeptidomimetics as does β5i. In vitro, one such compound was found to inhibit human T cell proliferation. Compounds of this class may have potential as therapeutics for autoimmune and inflammatory diseases with less mechanism‐based cytotoxicity than agents that also inhibit the constitutive proteasome.     

Area-specific subsidies and population dynamics: Evidence from the Australian zone tax offset

This paper studies the effect of the zone tax offset (ZTO), a place based income subsidy implemented in rural Australia since 1945. The policy was intended to improve the welfare of inhabitants and provide an incentive for settlement. Our empirical approach exploits the geographical discontinuity in the eligibility for the subsidy to identify its causal effect on population growth. Using data on population by locality from the historical censuses we find that the ZTO had a positive but only temporary effect on population growth in the targeted areas.     

Allocation of assembly tolerances to minimize costs

The cost and quality of an assembly depend on the processes used to manufacture its components. The specific processes and process settings are often dictated by the tolerances on the components. One long-standing challenge is allocating the assembly tolerance to components. Many methods have been proposed, most of which endeavor to minimize cost. We propose a tolerance allocation method that minimizes cost by jointly considering process variation and tolerance specifications. A cost model including processing cost, scrap cost, and quality loss is employed. The cost is minimized by a heuristic strategy. An overrunning clutch assembly case study is used to evaluate the method.     

Crosslinking effect on polydimethylsiloxane elastic modulus measured by custom‐built compression instrument

A macroscopic compression test utilizing a simple custom‐built instrument was employed to measure polydimethylsiloxane (PDMS) elastic modulus. PDMS samples with varying crosslinking density were prepared with the elastomer base to the curing agent ratio ranging from 5 : 1 to 33 : 1. The PDMS network elastic modulus varied linearly with the amount of crosslinker, ranging from 0.57 MPa to 3.7 MPa for the samples tested. PDMS elastic modulus in MPa can be expressed as 20 MPa/PDMS base to curing agent ratio. This article describes a simple method for measuring elastic properties of soft polymeric materials. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41050.