Chapter 11. Exploiting Runtime Variation in Complete Solvers

2021 ◽  
Author(s):  
Carla P. Gomes ◽  
Ashish Sabharwal
Keyword(s):  
Formal Model ◽  
Negative Impact ◽  
Sat Solvers ◽  
Model Based ◽  
Heavy Tailed ◽  
Runtime Distributions ◽  
Over Time ◽  
The Way

It has become well know over time that the performance of backtrack-style complete SAT solvers can vary dramatically depending on “little” details of the heuristics used, such as the way one selects the next variable to branch on and in what order the possible values are assigned to the variable. Extreme variations can result even from simple tie breaking mechanisms necessarily employed in all SAT solvers. The discovery of this extreme runtime variation has been both a stumbling block and an opportunity. This chapter focuses on providing an understanding of this intriguing phenomenon, particularly in terms of the so-called heavy tailed nature of the runtime distributions of systematic SAT solvers. It describes a simple formal model based on expensive mistakes to explain runtime distributions seen in practice, and discusses randomization and restart strategies that can be used to effectively overcome the negative impact of heavy tailed behavior. Finally, the chapter discusses the notion of backdoor variables, which explain the unexpectedly short runs one also often sees in practice.

The Negative Impact of Biological Variation in the Effect and Clearance of Warfarin on Methods for Prediction of Dose Requirements

1986 ◽  
Vol 56 (03) ◽  
pp. 371-375 ◽  
Author(s):  
Peretz Weiss ◽  
Hillel Halkin ◽  
Shlomo Almog
Keyword(s):  
Individual Variation ◽  
Negative Impact ◽  
Warfarin Dose ◽  
Empirical Therapy ◽  
Maintenance Phase ◽  
Individual Variability ◽  
Dose Prediction ◽  
Group I ◽  
Over Time ◽  
Variance Explained

SummaryWithin-individual variation over time in the clearance (Cl) and effect (PT%) of warfarin, was measured in 25 inpatients (group I) studied after standard single or individualized split loading doses and 1-3 times (n = 16) 8-16 weeks later during maintenance. Mean Cl (2.5 α 0.9 ml/min) was similar in both phases but significant changes occurred in 6/16 patients, exceeding those expected from within-individual variation alone (defined by its 95% tolerance limits -24% to +62%). Initial PT% (21 α 5) was unaffected by dosing schedule, total or free plasma warfarin, varying between patients by only 18-24%. Mean initial and maintenance dose-PT% ratios (8.2 mg/d: 21% and 4.1 mg/d: 40%) were similar but significant changes in sensitivity to warfarin occurred in 4/16 patients. In group I and 64 other outpatients on maintenance therapy, between-individual variability was 36-52% for Cl and 49-56% for effect. PT% correlated best (r = 0.56) with free and total plasma warfarin but poorly with dose (r = 0.29), with only 30% of PT% variance explained at best, due to high between patient variability.Warfarin dose prediction whether based on extrapolation from initial effects to the maintenance phase, or on iterative methods not allowing for between- or within-patient variation in warfarin clearance or effect which may occur independently over time, have not improved on empirical therapy. This, due to the elements of biological variability as well as the intricacy of the warfarin - prothrombin complex interaction not captured by any kinetic-dynamic model used for prediction to date.

PERANAN PEREMPUAN DALAM MEMBINA KESADARAN BERAGAMA ANAK

2019 ◽  
Vol 10 (1) ◽  
pp. 83-104
Author(s):  
Nursyam Nursyam
Keyword(s):  
Religious Education ◽  
Negative Impact ◽  
Muslim World ◽  
First Person ◽  
Good Care ◽  
Religious Dimension ◽  
The Gift ◽  
The Way ◽  
At Home

Children are a gift from Allah SWT that is always expected by every family. However, not everyone (parents) can take good care of their children according to what is commanded by Allah through religious teachings. For various reasons and reasons, parents no longer pay attention to children's religious education. In the end, the negative impact will be felt by parents even more so for their own children. To be able to form a religious awareness of children, the mother as the first person known to the child, then the mother needs to provide an understanding of the religious dimension of children is important, the child is essentially a mandate from Allah SWT that must be grateful, and we as Muslims must carry out the mandate with good and right. The way to be grateful for the gift of God in the form of children is through caring for, caring for, and educating and coaching the characters properly and correctly, so that they will not become weak children, both physically and mentally, and weak in faith and weak in their worldly lives. The aim of education is to be a perfect Muslim, who has faith and fear Allah. Mother as a parent is the first primary educator for children, before the child knows the outside world, first the child knows the mother and after that his father is the closest person to the child. As for women's efforts in fostering religious awareness as follows: to destroy personality, to form good habits , forming civilizations in the Muslim world and helping to encourage them to encourage things that lead to obedience to God and educate them with different ways of worship. Like prayer, recitation, prayer at home and at school.

Has Aid Helped in Pakistan?

1997 ◽  
Vol 36 (4II) ◽  
pp. 947-957 ◽  
Author(s):  
Shahrukh Rafi Khan
Keyword(s):  
Economic Growth ◽  
Negative Impact ◽  
Negative Association ◽  
Causal Impact ◽  
The Impact ◽  
Over Time

This paper has a two-fold objective: first, to examine the terms on which Pakistan receives aid and whether its debt situation is sustainable, and second, to examine the impact of aid and debt on economic growth. It is found that there is little encouraging that can be said about how the terms on which Pakistan has received aid over time have changed, and its current debt situation is not sustainable. Also reported is the analysis done elsewhere which shows that aid has a negative (Granger) causal impact on GDP, and aid has a robust negative impact on economic growth after controlling for supplyside shocks. We provide various reasons for this negative association.

Conclusion

2018 ◽  
Author(s):  
Manuel Fröhlich ◽  
Abiodun Williams
Keyword(s):  
Security Council ◽  
International Context ◽  
Peace And Security ◽  
Executive Action ◽  
Trends Over Time ◽  
The Impact ◽  
Over Time ◽  
The Way ◽  
Guiding Questions

The Conclusion returns to the guiding questions introduced in the Introduction, looking at the way in which the book’s chapters answered them. As such, it identifies recurring themes, experiences, structures, motives, and trends over time. By summarizing the result of the chapters’ research into the interaction between the Secretaries-General and the Security Council, some lessons are identified on the changing calculus of appointments, the conditions and relevance of the international context, the impact of different personalities in that interaction, the changes in agenda and composition of the Council as well as different formats of interaction and different challenges to be met in the realm of peace and security, administration, and reform, as well as concepts and norms. Taken together, they also illustrate the potential and limitations of UN executive action.

Civil Society in UN Peacebuilding Discourse

2017 ◽  
Author(s):  
Laura J. Shepherd
Keyword(s):  
Civil Society ◽  
United Nations ◽  
Local Knowledge ◽  
Political Legitimacy ◽  
Civil Society Organizations ◽  
Conceptual Domain ◽  
Close Analysis ◽  
The United Nations ◽  
Over Time ◽  
The Way

Chapter 5 outlines the ways in which civil society is largely associated with “women” and the “local,” as a spatial and conceptual domain, and how this has implications for how we understand political legitimacy and authority. The author argues that close analysis reveals a shift in the way in which the United Nations as a political entity conceives of civil society over time, from early engagement with non-governmental organisations (NGOs) to the more contemporary articulation of civil society as consultant or even implementing partner. Contemporary UN peacebuilding discourse, however, constitutes civil society as a legitimating actor for UN peacebuilding practices, as civil society organizations are the bearers/owners of certain forms of (local) knowledge.

Imagery in the Book of Revelation

2020 ◽  
pp. 52-67
Author(s):  
Konrad Huber
Keyword(s):  
Reception History ◽  
Book Of Revelation ◽  
Imperial Cult ◽  
Emotional Effect ◽  
Greco Roman ◽  
Different Types ◽  
Figurative Speech ◽  
Theological Message ◽  
Over Time ◽  
The Way

The chapter first surveys different types of figurative speech in Revelation, including simile, metaphor, symbol, and narrative image. Second, it considers the way images are interrelated in the narrative world of the book. Third, it notes how the images draw associations from various backgrounds, including biblical and later Jewish sources, Greco-Roman myths, and the imperial cult, and how this enriches the understanding of the text. Fourth, the chapter looks at the rhetorical impact of the imagery on readers and stresses in particular its evocative, persuasive, and parenetic function together with its emotional effect. And fifth, it looks briefly at the way reception history shows how the imagery has engaged readers over time. Thus, illustrated by numerous examples, it becomes clear how essentially the imagery of the book of Revelation constitutes and determines its theological message.

scholarly journals Framing of visual content shown on popular social media may affect viewers’ attitudes to threatened species

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fernando Ballejo ◽  
Pablo Ignacio Plaza ◽  
Sergio Agustín Lambertucci
Keyword(s):  
Social Media ◽  
Threatened Species ◽  
Social Medium ◽  
Visual Content ◽  
Wildlife Species ◽  
Mammalian Predators ◽  
Negative Comments ◽  
Over Time ◽  
The Way

AbstractContent published on social media may affect user’s attitudes toward wildlife species. We evaluated viewers’ responses to videos published on a popular social medium, focusing particularly on how the content was framed (i.e., the way an issue is conveyed to transmit a certain meaning). We analyzed videos posted on YouTube that showed vultures interacting with livestock. The videos were negatively or positively framed, and we evaluated viewers’ opinions of these birds through the comments posted. We also analyzed negatively framed videos of mammalian predators interacting with livestock, to evaluate whether comments on this content were similar to those on vultures. We found that the framing of the information influenced the tone of the comments. Videos showing farmers talking about their livestock losses were more likely to provoke negative comments than videos not including farmer testimonies. The probability of negative comments being posted on videos about vultures was higher than for mammalian predators. Finally, negatively framed videos on vultures had more views over time than positive ones. Our results call for caution in the presentation of wildlife species online, and highlight the need for regulations to prevent the spread of misinformed videos that could magnify existing human-wildlife conflicts.

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