Chapter 25. Model Counting

2021 ◽  
Author(s):  
Carla P. Gomes ◽  
Ashish Sabharwal ◽  
Bart Selman
Keyword(s):  
Local Search ◽  
Upper Bound ◽  
Probabilistic Inference ◽  
Efficient Algorithms ◽  
Propositional Formula ◽  
Exact Methods ◽  
Complete Problem ◽  
Model Counting ◽  
New Ideas

Model counting, or counting the number of solutions of a propositional formula, generalizes SAT and is the canonical #P-complete problem. Surprisingly, model counting is hard even for some polynomial-time solvable cases like 2-SAT and Horn-SAT. Efficient algorithms for this problem will have a significant impact on many application areas that are inherently beyond SAT, such as bounded-length adversarial and contingency planning, and, perhaps most importantly, general probabilistic inference. Model counting can be solved, in principle and to an extent in practice, by extending the two most successful frameworks for SAT algorithms, namely, DPLL and local search. However, scalability and accuracy pose a substantial challenge. As a result, several new ideas have been introduced in the last few years that go beyond the techniques usually employed in most SAT solvers. These include division into components, caching, compilation into normal forms, exploitation of solution sampling methods, and certain randomized streamlining techniques using special constraints. This chapter discusses these techniques, exploring both exact methods as well as fast estimation approaches, including those that provide probabilistic or statistical guarantees on the quality of the reported lower or upper bound on the model count.

Why Is Safe Science Good Science?

2018 ◽  
Author(s):  
Camilla Kao ◽  
Che-I Kao ◽  
Russell Furr
Keyword(s):  
Decision Making ◽  
Design Thinking ◽  
Good Science ◽  
Safety Issues ◽  
Safety Requirements ◽  
The Arts ◽  
Hands On ◽  
Obvious Benefit ◽  
New Ideas

In science, safety can seem unfashionable. Satisfying safety requirements can slow the pace of research, make it cumbersome, or cost significant amounts of money. The logic of rules can seem unclear. Compliance can feel like a negative incentive. So besides the obvious benefit that safety keeps one safe, why do some scientists preach "safe science is good science"? Understanding the principles that underlie this maxim might help to create a strong positive incentive to incorporate safety into the pursuit of groundbreaking science.<div><br></div><div>This essay explains how safety can enhance the quality of an experiment and promote innovation in one's research. Being safe induces a researcher to have <b>greater control</b> over an experiment, which reduces the <b>uncertainty</b> that characterizes the experiment. Less uncertainty increases both <b>safety</b> and the <b>quality</b> of the experiment, the latter including <b>statistical quality</b> (reproducibility, sensitivity, etc.) and <b>countless other properties</b> (yield, purity, cost, etc.). Like prototyping in design thinking and working under the constraint of creative limitation in the arts, <b>considering safety issues</b> is a hands-on activity that involves <b>decision-making</b>. Making decisions leads to new ideas, which spawns <b>innovation</b>.</div>

Evaluating the sufficiency of proposed security measures in favour of building objects

2021 ◽  
Vol 12 (1) ◽  
pp. 66-66
Author(s):  
Josef Reitšpís ◽  
Jozefína Drotárová
Keyword(s):  
Limited Area ◽  
Security Measures ◽  
Exact Methods ◽  
Technical Standards ◽  
Security Environment ◽  
Intentional Actions ◽  
Protection Systems ◽  
Level Of Knowledge ◽  
Satisfactory Answer

Security is understood as one of the basic life needs of people. However, it is necessary to realize that security is a natural quality of the environment where people live and is designated as a security environment. The need for sacurity is part of implementing sacurity measures that are created in compliance with a certain level of knowledge and needs. The content of this process can be characterized as a set of answers to primary questions (What is to be protected? – protected interest, Why to protect?, What to protect from? – threats) and secondary questions (Who will provide the protection?, How will the protection be provided?, When will the protection be provided?, By means of what will the protection be provided?, What price will the protection be provided for? etc.). From this viewpoint it is necessary to pay attention primarily to the problems concerning property protection from intentional actions focusing on protecting a particular building onject. In case of building objects it is primarily about the protection of tangible and intangible properties that are part of a particular limited area (mostly a building object) that is in possession or administration of a particular state or a private subject. The issues are dealt with by legal regulations, technical standards and various technical books. These usually concentrate on a particular area, kind of a building object and/or environment. However, none of them focuses on the property protection in a complex way and does not provide a satisfactory answer to the question "How to create protection systems in view of their sufficiency, complexity and balance in the technical and economic spheres?" That is why it is a social interest to search for new standardized procedures based on exact methods by means of which it will be possible, in empiric or intuitive ways, to exactly evaluate the effectivness of the existing or proposed property protection systems, including the formal desposition of results in project solutions Keywords: Project, Project documentation, Attack, Intervention and Detection time, Resistance of a building object, Modeling, Simulating

scholarly journals Penjadwalan Tenaga Kebidanan Menggunakan Algoritma Memetika

2018 ◽  
Vol 8 (1) ◽  
pp. 99
Author(s):  
A. Y. Erwin Dodu ◽  
Deny Wiria Nugraha ◽  
Subkhan Dinda Putra
Keyword(s):  
Genetic Algorithm ◽  
Local Search ◽  
Public Hospital ◽  
Memetic Algorithm ◽  
Optimal Schedule ◽  
Scheduling System ◽  
Local Search Methods ◽  
Evolution Algorithm ◽  
Central Sulawesi

The problem of midwife scheduling is one of the most frequent problems in hospitals. Midwife should be available 24 hours a day for a full week to meet the needs of the patient. Therefore, good or bad midwife scheduling result will have an impact on the quality of care on the patient and the health of the midwife on duty. The midwife scheduling process requires a lot of time, effort and good cooperation between some parties to solve this problem that is often faced by the Regional Public Hospital Undata Palu Central Sulawesi Province. This research aimed to apply Memetics algorithm to make scheduling system of midwifery staff at Regional Public Hospital Undata Palu Central Sulawesi Province that can facilitate the process of midwifery scheduling as well as to produce optimal schedule. The scheduling system created will follow the rules and policies applicable in the hospital and will also pay attention to the midwife's preferences on how to schedule them according to their habits and needs. Memetics algorithm is an optimization algorithm that combines Evolution Algorithm  and Local Search method. Evolution Algorithm in Memetics Algorithm generally refers to Genetic Algorithm so that the characteristics of Memetics Algotihm are identical with  Genetic Algorithm characteristics with the addition of Local Search methods. Local Search in Memetic Algorithm aims to improve the quality of an individual so it is expected to accelerate the time to get a solution.

scholarly journals The Computational Complexity of Probabilistic Planning

1998 ◽  
Vol 9 ◽  
pp. 1-36 ◽  
Author(s):  
M. L. Littman ◽  
J. Goldsmith ◽  
M. Mundhenk
Keyword(s):  
Computational Complexity ◽  
Efficient Algorithms ◽  
Boolean Satisfiability ◽  
Complexity Classes ◽  
Probabilistic Planning ◽  
Plan Evaluation ◽  
Partially Ordered ◽  
Boolean Satisfiability Problem ◽  
Complete Problem ◽  
Planning Problems

We examine the computational complexity of testing and finding small plans in probabilistic planning domains with both flat and propositional representations. The complexity of plan evaluation and existence varies with the plan type sought; we examine totally ordered plans, acyclic plans, and looping plans, and partially ordered plans under three natural definitions of plan value. We show that problems of interest are complete for a variety of complexity classes: PL, P, NP, co-NP, PP, NP^PP, co-NP^PP, and PSPACE. In the process of proving that certain planning problems are complete for NP^PP, we introduce a new basic NP^PP-complete problem, E-MAJSAT, which generalizes the standard Boolean satisfiability problem to computations involving probabilistic quantities; our results suggest that the development of good heuristics for E-MAJSAT could be important for the creation of efficient algorithms for a wide variety of problems.

Mobile Learning

2011 ◽  
pp. 103-128
Author(s):  
Marija Zelic
Keyword(s):  
Mobile Learning ◽  
Relevant Literature ◽  
Learning Systems ◽  
Personal Digital Assistants ◽  
Desktop Computers ◽  
Efficiency And Effectiveness ◽  
E Learning ◽  
New Ideas ◽  
Access To Knowledge

Mobile learning, as the “portable and personal” fashion of e-learning, is intended to enhance the efficiency and effectiveness of learning in the context of handheld terminals. Most present-day learning systems run on desktop computers and are not designed for use on mobile devices such as mobile phones, smart phones, Personal Digital Assistants, etc. Mobile learning systems aim to improve the quality of learning by providing mobile learners with an easy, contextualized and ubiquitous access to knowledge. This chapter gives an overview of the current state of knowledge and research in the m-learning domain, describes issues and problems pertinent to mobile learning and offers our approach to solving these problems in the form of a mobile intelligent tutoring model we are currently developing. Given the present absence of relevant literature and referent material we think that this chapter provides developers with some new ideas.

The Key of Franchising Chains and Human Resource Management

2016 ◽  
pp. 209-222
Author(s):  
Ana Branca Carvalho ◽  
Fernanda Nogueira
Keyword(s):  
Quality Of Life ◽  
Economic Growth ◽  
Resource Management ◽  
Human Resources ◽  
Human Resource Management ◽  
Human Resource ◽  
Low Cost ◽  
Human Resources Management ◽  
New Ideas

This chapter aims to contribute to the literature and aid in developing a theoretical and practical framework in the area of organization and human resource. With contributions and research from different perspectives, this paper is an essential source for students, researchers and managers in the franchising chains. There has been an increased interest in human resources problems and in new forms of organizations. The concept of Trust can be combined to satisfy the needs of people seeking better quality-of-life. This analyzes the problems of human resources management features of franchising chain business management. The franchising chains involve two aspects: the relation based in trust and a group that develops an innovation idea. It contributes to economic growth, as a pillar to support other complementary activities with a low cost. This system contributes to employment growth and regional wealth, contributes to new ideas helps create new services with high value, promotes establishment of international cooperation networks, and yields a number of additional benefits.

Quality of Service for Multimedia and Real-Time Services

2010 ◽  
Vol 5 (4) ◽  
pp. 1-22
Author(s):  
F. W. Albalas ◽  
B. A. Abu-Alhaija ◽  
A. Awajan ◽  
A. Awajan ◽  
Khalid Al-Begain
Keyword(s):  
Decision Making ◽  
Quality Of Service ◽  
Real Time ◽  
Qos Routing ◽  
Routing Algorithms ◽  
Complete Problem ◽  
Filtering Technique ◽  
Np Complete ◽  
Multiple Metrics

New web technologies have encouraged the deployment of various network applications that are rich with multimedia and real-time services. These services demand stringent requirements are defined through Quality of Service (QoS) parameters such as delay, jitter, loss, etc. To guarantee the delivery of these services QoS routing algorithms that deal with multiple metrics are needed. Unfortunately, QoS routing with multiple metrics is considered an NP-complete problem that cannot be solved by a simple algorithm. This paper proposes three source based QoS routing algorithms that find the optimal path from the service provider to the user that best satisfies the QoS requirements for a particular service. The three algorithms use the same filtering technique to prune all the paths that do not meet the requirements which solves the complexity of NP-complete problem. Next, each of the three algorithms integrates a different Multiple Criteria Decision Making method to select one of the paths that have resulted from the route filtering technique. The three decision making methods used are the Analytic Hierarchy Process (AHP), Multi-Attribute Utility Theory (MAUT), and Kepner-Tregoe KT. Results show that the algorithms find a path using multiple constraints with a high ability to handle multimedia and real-time applications.

scholarly journals An Improved Iterated Local Search Algorithm for the Static Partial Repositioning Problem in Bike-Sharing System

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Qiong Tang ◽  
Zhuo Fu ◽  
Dezhi Zhang ◽  
Meng Qiu ◽  
Minyi Li
Keyword(s):  
Local Search ◽  
Search Algorithm ◽  
Iterated Local Search ◽  
Target Number ◽  
Absolute Deviation ◽  
Penalty Cost ◽  
Bike Sharing ◽  
Single Vehicle ◽  
Loading And Unloading

In this paper, a single-vehicle static partial repositioning problem (SPRP) is investigated, which distinguishes the user dissatisfaction generated by different stations. The overall objective of the SPRP is to minimize the weighted sum of the total operational time and the total absolute deviation from the target number of bikes at all stations. An iterated local search is developed to solve this problem. A novel loading and unloading quantity adjustment operator is proposed to further improve the quality of the solution. Experiments are conducted on a set of instances from 30 to 300 stations to demonstrate the effectiveness of the proposed customized solution algorithm as well as the adjustment operator. Using a small example, this paper also reveals that the unit penalty cost has an effect on the repositioning strategies.

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