scholarly journals Reliable CPS Design for Unreliable Hardware Platforms

Author(s):  
Wanli Chang ◽  
Swaminathan Narayanaswamy ◽  
Alma Pröbstl ◽  
Samarjit Chakraborty

AbstractToday, many battery-operated cyber-physical systems (CPS) ranging from domestic robots, to drones, and electric vehicles are highly software-intensive. The software in such systems involves multiple feedback control loops that implement different functionality. How these control loops are designed is closely related to both the semiconductor aging of the processors on which the software is run and also the aging of the batteries in these systems. For example, sudden acceleration in an electric vehicle can negatively impact the health of the vehicle’s battery. On the other hand, processors age over time and stress, impacting the execution of control algorithms and thus the control performance. With increasing semiconductor scaling, and our increasing reliance on battery-operated devices, these aging effects are of concern for the lifetime of these devices. Traditionally, the design of the control loops focused only on control-theoretic metrics, related to stability and performance (such as peak overshoot or settling time). In this chapter we show that such controller design techniques that are oblivious of the characteristics of the hardware implementation platform dramatically worsen the battery behaviour and violate the safety requirement with processor aging. However, with proper controller design these effects can be mitigated—thereby improving the lifetime of the devices.

2018 ◽  
Author(s):  
Alasdair D F Clarke ◽  
Jessica Irons ◽  
Warren James ◽  
Andrew B. Leber ◽  
Amelia R. Hunt

A striking range of individual differences has recently been reported in three different visual search tasks. These differences in performance can be attributed to strategy, that is, the efficiency with which participants control their search to complete the task quickly and accurately. Here we ask if an individual's strategy and performance in one search task is correlated with how they perform in the other two. We tested 64 observers in the three tasks mentioned above over two sessions. Even though the test-retest reliability of the tasks is high, an observer's performance and strategy in one task did not reliably predict their behaviour in the other two. These results suggest search strategies are stable over time, but context-specific. To understand visual search we therefore need to account not only for differences between individuals, but also how individuals interact with the search task and context. These context-specific but stable individual differences in strategy can account for a substantial proportion of variability in search performance.


2020 ◽  
pp. 174702182092919 ◽  
Author(s):  
Alasdair DF Clarke ◽  
Jessica L Irons ◽  
Warren James ◽  
Andrew B Leber ◽  
Amelia R Hunt

A striking range of individual differences has recently been reported in three different visual search tasks. These differences in performance can be attributed to strategy, that is, the efficiency with which participants control their search to complete the task quickly and accurately. Here, we ask whether an individual’s strategy and performance in one search task is correlated with how they perform in the other two. We tested 64 observers and found that even though the test–retest reliability of the tasks was high, an observer’s performance and strategy in one task was not predictive of their behaviour in the other two. These results suggest search strategies are stable over time, but context-specific. To understand visual search, we therefore need to account not only for differences between individuals but also how individuals interact with the search task and context.


2020 ◽  
Vol 33 (1) ◽  
pp. 96-125 ◽  
Author(s):  
Devin Judge-Lord ◽  
Constance L. McDermott ◽  
Benjamin Cashore

Due to inconsistent concepts of regulatory stringency, scholars offer conflicting accounts about whether competing private governance initiatives “race to the bottom,” “ratchet up,” “converge,” or “diverge.” To remedy this, we offer a framework for more systematic comparisons across programs and over time. We distinguish three often-conflated measures of stringency: regulatory scope, prescriptiveness, and performance levels. Applying this framework, we compare competing U.S. forestry certification programs, one founded by environmental activists and their allies, the other by the national industry association. We find ‘upwardly divergent’ policy prescriptiveness: both programs increased in prescriptiveness, but this increase was greater for the activist-backed program. Furthermore, requirements added by the activist-backed program were more likely to impose costs on firms than requirements added by the industry-backed program, many of which may even benefit firms. These results are consistent with the hypothesis that industry-backed programs emphasize less costly types of stringency than activist-backed programs. They also reveal patterns of change that previous scholarship failed to anticipate, illustrating how disentangling types of stringency can improve theory building and testing.


Author(s):  
Melanie K. T. Takarangi ◽  
Deryn Strange

When people are told that their negative memories are worse than other people’s, do they later remember those events differently? We asked participants to recall a recent negative memory then, 24 h later, we gave some participants feedback about the emotional impact of their event – stating it was more or less negative compared to other people’s experiences. One week later, participants recalled the event again. We predicted that if feedback affected how participants remembered their negative experiences, their ratings of the memory’s characteristics should change over time. That is, when participants are told that their negative event is extremely negative, their memories should be more vivid, recollected strongly, and remembered from a personal perspective, compared to participants in the other conditions. Our results provide support for this hypothesis. We suggest that external feedback might be a potential mechanism in the relationship between negative memories and psychological well-being.


Author(s):  
Avi Max Spiegel

This chapter seeks to understand how Islamist movements have evolved over time, and, in the process, provide important background on the political and religious contexts of the movements in question. In particular, it shows that Islamist movements coevolve. Focusing on the histories of Morocco's two main Islamist movements—the Justice and Spirituality Organization, or Al Adl wal Ihsan (Al Adl) and the Party of Justice and Development (PJD)—it suggests that their evolutions can only be fully appreciated if they are relayed in unison. These movements mirror one another depending on the competitive context, sometimes reflecting, sometimes refracting, sometimes borrowing, sometimes adapting or even reorganizing in order to keep up with the other.


2020 ◽  
Vol 65 (4) ◽  
pp. 401-422
Author(s):  
Estelle Variot
Keyword(s):  
The One ◽  

"Etymological, Lexical and Semantic Correspondences in the Process of Feminization of Professional Names, Trades and Activities in French and Romanian Societies. The feminization of thought represented by language and of its varieties in the Roman World has allowed to highlight some convergences that come from a common linguistic heritage, often from Greek and Latin and some hesitation about adapting society to its realities. The feminization of some words which comes from an ancient process illustrates on the one hand the potential of the language and on the other hand some constraints sometimes linked to the society itself, which creates transitional periods, between matching grammatical correction and the evolution of linguistic uses over time. The possibilities of lexical enrichment (internal creation or loan) show the means available in French and Romanian and some convergences in the area of derivation, of lexical units and their etymologies. The grammatical perspective and word constructing methods make it possible to give keys for the feminization of names of trades or professions. Likewise, recording entries in the lexicon, their evolution, their assimilation or sometimes their forgetfulness, for the benefit of new constructions highlight the existence of objective and subjective criteria which teach us a lot about society as a whole. Keywords: feminization of professions, internal and external enrichment, suffixal match, use of words, grammar, lexicon, French and Romanian."


2010 ◽  
Vol 1 (1) ◽  
pp. 1-19
Author(s):  
Ahmed Akgunduz

AbstractIslamic Law is one of the broadest and most comprehensive systems of legislation in the world. It was applied, through various schools of thought, from one end of the Muslim world to the other. It also had a great impact on other nations and cultures. We will focus in this article on values and norms in Islamic law. The value system of Islam is immutable and does not tolerate change over time for the simple fact that human nature does not change. The basic values and needs (which can be called maṣlaḥa) are classified hierarchically into three levels: (1) necessities (Ḍarūriyyāt), (2) convenience (Ḥājiyyāt), and (3) refinements (Kamāliyyāt=Taḥsīniyyāt). In Islamic legal theory (Uṣūl al‐fiqh) the general aim of legislation is to realize values through protecting and guaranteeing their necessities (al-Ḍarūriyyāt) as well as stressing their importance (al‐ Ḥājiyyāt) and their refinements (taḥsīniyyāt).In the second part of this article we will draw attention to Islamic norms. Islam has paid great attention to norms that protect basic values. We cannot explain all the Islamic norms that relate to basic values, but we will classify them categorically. We will focus on four kinds of norms: 1) norms (rules) concerned with belief (I’tiqādiyyāt), 2) norms (rules) concerned with law (ʿAmaliyyāt); 3) general legal norms (Qawā‘id al‐ Kulliyya al‐Fiqhiyya); 4) norms (rules) concerned with ethics (Wijdāniyyāt = Aḵlāqiyyāt = Ādāb = social and moral norms).


2020 ◽  
Vol 13 (2) ◽  
pp. 1
Author(s):  
E. M. Samogim ◽  
T. C. Oliveira ◽  
Z. N. Figueiredo ◽  
J. M. B. Vanini

The combine harvest for soybean crops market are currently available two types of combine with header or platform, one of conventional with revolving reel with metal or plastic teeth to cause the cut crop to fall into the auger header and the other called "draper" headers that use a fabric or rubber apron instead of a cross auger, there are few test about performance of this combine header for soybean in Mato Grosso State. The aim of this work was to evaluate the soybean harvesting quantitative losses and performance using two types combine header in four travel speed. The experiment was conducted during soybean crops season 2014/15, the farm Tamboril in the municipality of Pontes e Lacerda, State of Mato Grosso. The was used the experimental design of randomized blocks, evaluating four forward harvesting speeds (4 km h-1, 5 km h-1, 6 km h-1 and 7 km h-1), the natural crops losses were analyzed, loss caused by the combine harvester (combine header, internal mechanisms and total losses) and was also estimated the  field performance of each combine. Data were submitted to analysis of variance by F test and compared of the average by Tukey test at 5% probability. The results show the draper header presents a smaller amount of total loss and in most crop yield when compared with the conventional cross auger.


Relay Journal ◽  
2018 ◽  
pp. 360-381
Author(s):  
Gordon Myskow ◽  
Phillip A. Bennett ◽  
Hisako Yoshimura ◽  
Kyoko Gruendel ◽  
Takuto Marutani ◽  
...  

The distinction between Cooperative and Collaborative Learning approaches is not a clear one. Some use the terms interchangeably while others consider Cooperative Learning to be a type of Collaborative Learning. Still others clearly differentiate between them, characterizing Cooperative Learning as more highly structured in its procedures, involving a great deal of intervention by the teacher to plan and orchestrate group interactions. Collaborative Learning, on the other hand, presupposes some degree of learner autonomy-that groups can work effectively toward shared goals and monitor their own progress. This paper takes the view that the distinction between Cooperative and Collaborative Learning is a useful one and that both approaches can play valuable roles in fostering autonomous interaction. It argues that while Collaborative Learning formations may be the ultimate goal for teachers wishing to develop learner autonomy, Cooperative Learning is a valuable means for modeling the skills and abilities to help students get there. The discussion begins with an overview of the two approaches, focusing on their implementation in the Japanese educational context. It then presents seven highly structured Cooperative Learning activities and shows how they can be modified and extended over time to encourage more autonomous interaction.


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