动态全局约束：第一个视图

View-based Propagator Derivation

When implementing a propagator for a constraint, one must decide about variants: When implementing min, should one also implement max? Should one implement linear constraints both with unit and non-unit coefficients? Constraint variants are ubiquitous: implementing them requires considerable (if not prohibitive) effort and decreases maintainability, but will deliver better performance than resorting to constraint decomposition. This paper shows how to use views to derive perfect propagator variants. A model for views and derived propagators is introduced. Derived propagators are proved to be i…

Tractable Combinations of Global Constraints

We study the complexity of constraint satisfaction problems involving global constraints, i.e., special-purpose constraints provided by a solver and represented implicitly by a parametrised algorithm. Such constraints are widely used; indeed, they are one of the key reasons for the success of constraint programming in solving real-world problems. Previous work has focused on the development of efficient propagators for individual constraints. In this paper, we identify a new tractable class of constraint problems involving global constraints of unbounded arity. To do so, we combine structural …

Prefix-Projection Global Constraint for Sequential Pattern Mining

Sequential pattern mining under constraints is a challenging data mining task. Many efficient ad hoc methods have been developed for mining sequential patterns, but they are all suffering from a lack of genericity. Recent works have investigated Constraint Programming (CP) methods, but they are not still effective because of their encoding. In this paper, we propose a global constraint based on the projected databases principle which remedies to this drawback. Experiments show that our approach clearly outperforms CP approaches and competes well with ad hoc methods on large datasets.

Structural Decompositions for Problems with Global Constraints

A wide range of problems can be modelled as constraint satisfaction problems (CSPs), that is, a set of constraints that must be satisfied simultaneously. Constraints can either be represented extensionally, by explicitly listing allowed combinations of values, or implicitly, by special-purpose algorithms provided by a solver. Such implicitly represented constraints, known as global constraints, are widely used; indeed, they are one of the key reasons for the success of constraint programming in solving real-world problems. In recent years, a variety of restrictions on the structure of CSP inst…

基于MDD的通用全局约束

Generic Global Constraints based on MDDs

约束规划（CP）已成功地应用于约束满足和约束优化问题。各种各样的专门的全球限制提供了关键的援助，以实现一个良好的模型，可以利用问题的结构，在寻找解决方案。然而，一个关键的悬而未决的问题是表示“特设”的约束，不具有固有的组合性质，因此没有建模以及使用狭义的全球性约束。我们试图通过考虑搜索和编译的混合来解决这个问题。具体来说，我们建议使用简化的有序多值决策图（ROMDDs）作为通用全局约束的支持数据结构。我们给出了一个算法，用于维护广义弧一致性（GAC）在此约束下，分摊成本的GAC计算在一个根到叶路径的搜索树，而不需要渐近更多的空间比用于MDD。此外，我们提出了一种方法，用于在搜索过程中逐步保持减少属性的MDD，并展示了如何可以用于提供域蕴涵检测。最后，我们讨论了如何将我们的方法应用到其他类似的数据结构，如AOMDD和案例DAG。所使用的技术可以被看作是GAC算法对有限长度输入的正则语言约束的扩展。

全局约束推理的复杂性

The Complexity of Reasoning with Global Constraints

约束传播是约束编程成功的关键技术之一。为了减少搜索，与每个约束相关联的快速算法修剪变量的域。对于全局（或非二进制）约束，这种传播的成本可能比二进制约束的二次成本大得多。因此，我们研究的计算复杂性的推理与全局约束。我们首先讨论了一些与约束传播有关的重要问题。我们表明，这样的问题是棘手的一般，并确定不同问题的易处理性和难处理性之间的依赖关系。然后，我们演示了如何使用计算复杂性的工具，可以在设计和分析特定的全局约束。特别是，我们说明了如何可以使用计算复杂性来确定何时应执行较低级别的局部一致性，何时约束可以安全地推广，何时分解约束将减少修剪量，以及何时组合约束是易处理的。

A global constraint for closed itemset mining

Discovering the set of closed frequent patterns is one of the fundamental problems in Data Mining. Recent Constraint Programming (CP) approaches for declarative itemset mining have proven their usefulness and flexibility. But the wide use of reified constraints in current CP approaches raises many difficulties to cope with high dimensional datasets. This paper proposes CLOSED PATTERN global constraint which does not require any reified constraints nor any extra variables to encode efficiently the Closed Frequent Pattern Mining (CFPM) constraint. CLOSED-PATTERN captures the particular semantics…

A global constraint for the capacitated single-item lot-sizing problem

The goal of this paper is to set a constraint programming framework to solve lot-sizing problems. More specifically, we consider a single-item lot-sizing problem with time-varying lower and upper bounds for production and inventory. The cost structure includes time-varying holding costs, unitary production costs and setup costs. We establish a new lower bound for this problem by using a subtle time decomposition. We formulate this NP-hard problem as a global constraint and show that bound consistency can be achieved in pseudo-polynomial time and when not including the costs, in polynomial time…

全球变暖（软化全球约束）

On Global Warming (Softening Global Constraints)

我们描述软版本的全球基数约束和常规约束，有效的过滤算法保持域的一致性。对于这两个约束，软化是通过增强底层图来实现的。软化约束可以用来扩展Petit，Regin和Bessiere提出的过约束问题的元约束框架。

An Abstract Semantics of the Global View of Choreographies

We introduce an abstract semantics of the global view of choreographies. Our semantics is given in terms of pre-orders and can accommodate different lower level semantics. We discuss the adequacy of our model by considering its relation with communicating machines, that we use to formalise the local view. Interestingly, our framework seems to be more expressive than others where semantics of global views have been considered. This will be illustrated by discussing some interesting examples.