IT architecture meets the real (legal) world

Unfortunately for IT professionals, e-mail represents only the tip of the iceberg in how legal and regulatory duties will impact IT operations. In addition to privacy issues, regulators and other legal officials have already expressed interest in intruding into data center operations for audits of digital rights management (distribution of copyrighted materials) and taxes. They also want to determine whether e-commerce personalization engines have the impact of illegally redlining users. (Redlining is the illegal practices of a lending institution that denies loans or restricts the number of loans for certain areas of a community. There have also been redlining problems in the insurance industry.) Data centers house information, and information is of critical interest to legal and regulatory authorities. The net result is that IT architecture isn't just about technology any more. The last year's market realities made it clear that everyone must worry about the fiduciary realities of return on investment and total cost of ownership. Now that the rest of the world is catching up, IT architects need to deal with the legal realities imposed by governments and regulatory agencies. It is argued that companies that host e-mail should prepare to cooperate with law enforcement authorities and comply with search warrants or risk having their systems seized and carted away     

Logical approximation for program analysis

The abstract interpretation of programs relates the exact semantics of a programming language to a finite approximation of those semantics. In this article, we describe an approach to abstract interpretation that is based in logic and logic programming. Our approach consists of faithfully representing a transition system within logic and then manipulating this initial specification to create a logical approximation of the original specification. The objective is to derive a logical approximation that can be interpreted as a terminating forward-chaining logic program; this ensures that the approximation is finite and that, furthermore, an appropriate logic programming interpreter can implement the derived approximation. We are particularly interested in the specification of the operational semantics of programming languages in ordered logic, a technique we call substructural operational semantics (SSOS). We show that manifestly sound control flow and alias analyses can be derived as logical approximations of the substructural operational semantics of relevant languages.     

Using Physical and Logical Constraints for Invoice Understanding

This work presents a methodology for invoice understanding. The invoices of our domain can be grouped into classes according to their logo. The understanding phase is based on two knowledge levels: a specific knowledge for each class, called a document model; and knowledge on the whole domain of interest, called a domain model. The invoices of a known class are understood by its document model, while the invoices of an unknown class are understood by using the domain model. The main contribution of this work is related to the use of the physical and logical constraints of the domain of interest for document understanding, without using an OCR system. Our approach has been tested by some experiments that are intended to identify some regions within invoices of unknown classes. In most cases, the results have shown the reliability of the approach.     

Logical Equivalence for Subtyping Object and Recursive Types

Subtyping in first order object calculi is studied with respect to the logical semantics obtained by identifying terms that satisfy the same set of predicates, as formalised through an assignment system. It is shown that equality in the full first order ς-calculus is modelled by this notion, which in turn is included in a Morris-style contextual equivalence. U. de’Liguoro’s research was partially supported by project PRIN’05 prot. 2005015785_003.     

Deadlock Detection and Avoidance for Shared Logical Resources

Logical resources are defined as shared passive entities that can be concurrently accessed by multiple processes. Concurrency restrictions depend upon the mode or manner in which a process may manipulate a resource. Models incorporating these single unit resources can be used to analyze information locking for consistency and integrity purposes. Mode compatibility is defined and used to derive dead-lock detection and avoidance methods. These methods generalize well-known deadlock results for single unit resources by permitting greater concurrency while still guaranteeing data consistency. This model is applicable to the standard shared (read-only) and exclusive (read-write) access modes as well as a useful subset of those proposed in the CODASYL DBMS report.     

Logical Semantics for the Rewriting Calculus

The Rewriting Calculus has been proposed as a language for defining term rewriting strategies. Rules are explicitly represented as terms, and are applied explicitly to other terms to transform them. Sets of rules may be applied to (sets of) terms non-deterministically to obtain sets of results. Strategies are implemented as rules which accept other rules as arguments and apply them in certain ways. This paper describes work in progress to strengthen the Rewriting Calculus by giving it a logical semantics. Such a semantics can provide crucial guidance for studying the language and increasing its expressive power. The latter is demonstrated by adding support to the Rewriting Calculus for what we call higher-form rewriting, where rules rewrite other rules. The logical semantics used is based on ordered linear logic. The paper develops the ideas through several examples.     

A Deterministic Logical Semantics for Esterel

Esterel is a synchronous design language for the specification of reactive systems. There exist two main semantics for Esterel. On the one hand, the logical behavioral semantics provides a simple and compact formalization of the behavior of programs using SOS rules. But it does not ensure deterministic executions for all programs and all inputs. As non-deterministic programs have to be rejected as incorrect, this means it defines behaviors for incorrect programs, which is not convenient. On the other hand, the constructive semantics is deterministic (amongst other properties) but at the expense of a much more complex formalism. In this work, we construct and thoroughly analyze a new deterministic semantics for Esterel that retains the simplicity of the logical behavioral semantics, from which it derives. In our view, it provides a much better framework for formal reasoning about Esterel programs.     

Logical sentences and searches

Abstract  A study of 13–14 year-old students' performance on two parallel logical reasoning tasks related to database searches is reported. In one task, given a logical sentence defining a search, students had to construct the equivalent data structure. In the other, given a data structure, they had to construct the equivalent logical sentence. Binary logical sentences including AND, OR and NOT were investigated, including tautology and contradiction. Students were more successful with sentences using AND than with sentences using OR. Negation generally produced difficulties, and essentially none could manage tautology and contradiction. Sentences using OR were more difficult, especially when they involved NOT. A common pattern was to treat OR as if it were AND. The two tasks, though formally parallel, were very different in difficulty, with the construction of sentences from a data structure being the more difficult. Both tasks were administered before and after training in the use of a database. A negligible difference in performance was seen.     

Model for knowledge and legal expert systems

This paper presents a four layer model for working with legal knowledge in expert systems. It distinguishes five sources of knowledge. Four contain basic legal knowledge found in published and unpublished sources. The fifth consists of legal metaknowledge. In the model the four basic legal knowledge sources are placed at the lowest level. The metaknowledge is placed at levels above the other four knowledge sources. The assumption is that the knowledge is represented only once. The use of metaknowledge at various levels should make it possible to use the appropriate knowledge for the problem presented to the system. The knowledge has to be represented as closely to the original format as possible for this purpose. Suitable representation formalisms for the various types of knowledge in the five knowledge sources are discussed. It is not possible to indicate a best representation formalism for each knowledge source.     

绿色评价模型的互模拟等价及逻辑保持

绿色计算中,复杂系统的绿色评价是一个重要的研究课题,其核心任务是判断运行时时间、空间资源消耗是否满足环境约束或限定.设计时,采用模型检测技术,自动、完备、高效地进行绿色评价,是一种新颖且有效的解决方案,但可能出现的状态爆炸问题将影响评价成败或效率.引入随机决策过程作为绿色评价模型;用时态逻辑刻画包含行为正确性及时间、空间资源约束的绿色评价指标;定义不确定语义理解下评价模型状态的互模拟等价规则,给出互模拟商的构造方法以及商模型调度,并比较等价语义下的行为机理;运用结构化归纳法证明互模拟等价保持评价结论.分析表明,互模拟等价可用作状态约简手段,为基于模型的绿色评价提供理论支撑和技术手段.     

Acceptable legal standards for software

The author discusses the legal issues that are involved in software protection. She discusses legal actions open to users who get a system that does not perform as expected and have exhausted all remedies that do not involve litigation. She examines how the law treats software, covering liability limitations and court actions regarding fraud or misrepresentation as well as injury and damage caused by software. The author discusses the inadequacy of current laws and offers recommendations for remedying the situation     

A Logical Architecture for Active Network Management

This paper focuses on improving network management by exploiting the potential of “doing” of the Active Networks technology, together with the potential of “planning,” which is typical of the artificial intelligent systems. We propose a distributed multiagent architecture for Active Network management, which exploits the dynamic reasoning capabilities of the Situation Calculus in order to emulate the reactive behavior of a human expert to fault situations. The information related to network events is generated by programmable sensors deployed across the network. A logical entity collects this information, in order to merge it with general domain knowledge, with a view to identifying the root causes of faults, and to deciding on reparative actions. The logical inference system has been devised to carry out automated isolation, diagnosis, and even repair of network anomalies, thus enhancing the reliability, performance, and security of the network. Experimental results illustrate the Reasoner capability of correctly recognizing fault situations and undertaking management actions.     

Logical programming for the telegram analysis problem

The telegram analysis problem posed by Henderson and Snowdon has been repeatedly taken into account. This paper adds yet another contribution to the literature on this problem. We propose rigorous specification methods, and describe how programs can be derived from BNF to Definite Clause Grammar in Prolog by two different methods. One method is especially useful for large scale problems and has been applied to file manipulation, and the other is applicable to simple problems.     

A Logical Framework for Knowledge Base Maintenance

1IntroductionAmongalltheoreticalworksonknowledgebasemaintenance,Doyle's"TruthMaintenanceSystem"[1]andAlchourr6n,GdrdenforsandMakinson's"LogicofThe-oryChange"[2]playthemostimportantrole.'Inthe"TruthMaintenanceSystem",everylawcontainedinaknowledgebase,orabaseforshort,isspecifiedby"in"and"out"status,whichindicatethededuciblerelationsbetweenthelawsofthebase.Whenalawofthebaseisrejectedbytheusers3arevisedversionofthebasecanbeobtainedbymechanicallychangingthe"in"and"out"statusofthelaws.Thismech…     

Logical/linear operators for image curves

We propose a language for designing image measurement operators suitable for early vision. We refer to them as logical/linear (L/L) operators, since they unify aspects of linear operator theory and Boolean logic. A family of these operators appropriate for measuring the low-order differential structure of image curves is developed. These L/L operators are derived by decomposing a linear model into logical components to ensure that certain structural preconditions for the existence of an image curve are upheld. Tangential conditions guarantee continuity, while normal conditions select and categorize contrast profiles. The resulting operators allow for coarse measurement of curvilinear differential structure (orientation and curvature) while successfully segregating edge-and line-like features. By thus reducing the incidence of false-positive responses, these operators are a substantial improvement over (thresholded) linear operators which attempt to resolve the same class of features