Interfacing Oz with the PCTE OMS: A Case Study of Integrating a Legacy System with a Standard Object Management System

The integration of a legacy system and a standard Object Management System (OMS) is often a very challenging task. This paper details a case study, our experiment in interfacing Oz with the PCTE (Portable Common Tool Environment) Object Management System. Oz is a multi-user process-centered software development environment that has been under development in our lab since 1987, originally under the name Marvel. PCTE is a specification that defines a language-independent interface providing support mechanisms for software engineering environments (SEE). One of the premises of PCTE is that, in theory, an SEE such as Oz can be built (or extended) using the services provided by PCTE. The purpose of our experiment was to study how a legacy system such as Oz can be integrated into a new environment framework, e.g., PCTE. The architecture of the legacy system and the services of the framework are the key factors in the integration approach. Because Oz historically has included a native OMS, our experiment focused on modifying Oz to use the PCTE OMS, which has an open and standard API. This paper describes how several Oz components were changed to interface to the PCTE OMS. The resulting proof-of-concept hybrid system has process control and integration services provided by Oz, and data integration services provided in part by PCTE. We discuss in depth the solutions to the concurrency control problems that arise in such an environment, where Oz and PCTE use different approaches to transaction management (i.e., each has its own transaction manager). The PCTE implementation used in our experiment was the Emeraude PCTE V 12.5.1, and the Oz version was V 1.0.1.     

MAGAD-BFS: A learning method for Beta fuzzy systems based on a multi-agent genetic algorithm

This paper proposes a learning method for Beta fuzzy systems (BFS) based on a multiagent genetic algorithm. This method, called Multi-Agent Genetic Algorithm for the Design of BFS has two advantages. First, thanks to genetic algorithms (GA) efficiency, it allows to design a suitable and precise model for BFS. Second, it improves the GA convergence by reducing rule complexity thanks to the distributed implementation by multi-agent approach. Dynamic agents interact to provide an optimal solution in order to obtain the best BFS reaching the balance interpretability-precision. The performance of the method is tested on a simulated example.     

一种基于令牌的认证密钥交换协议

对称密钥系统较之非对称密钥系统具有惊人的速度优势,但是管理对称密钥系统的密钥却是需要解决的一个难题。Diffie-Hellman密钥交换是一个可以使通信双方在不可信信道上一同建立共享密钥,并使之应用于后继对称密钥通信系统的一种密码协议。应当注意到,Diffie-Hellman密钥交换协议不支持对所建立的密钥的认证。处于两个通信参与者Alice和Bob之间的一个恶意的攻击者Mallary可以主动操纵协议运行过程的信息并成功实施所谓的中间人攻击(man-in-the-middleattack)。因此为了能够真正在两个通信参与者Alice和Bob之间协商一个密钥就必须确保他们在协议运行过程中收到的信息的确是来自真实的对方。本文就是给出一种基于令牌的认证密钥交换协议以对Diffie-Hellman密钥交换协议进行改进。这对于电子商务等等很多网络应用而言是至关重要的。本文也给出了这种协议的安全性分析,并描述了基于JAVA的实现。     

Programming languages for distributed applications

Much progress has been made in distributed computing in the areas of distribution structure, open computing, fault tolerance, and security. Yet, writing distributed applications remains difficult because the programmer has to manage models of these areas explicitly. A major challenge is to integrate the four models into a coherent development platform. Such a platform should make it possible to cleanly separate an application’s functionality from the other four concerns. Concurrent constraint programming, an evolution of concurrent logic programming, has both the expressiveness and the formal foundation needed to attempt this integration. As a first step, we have designed and built a platform that separates an application’s functionality from its distribution structure. We have prototyped several collaborative tools with this platform, including a shared graphic editor whose design is presented in detail. The platform efficiently implements Distributed Oz, which extends the Oz language with constructs to express the distribution structure and with basic primitives for open computing, failure detection and handling, and resource control. Oz appears to the programmer as a concurrent object-oriented language with dataflow synchronization. Oz is based on a higher-order, state-aware, concurrent constraint computation model. Seif Haridi, Ph.D.: He received his Ph.D. in computer science in 1981 from the Royal Institute of Technology, Sweden. After spending 18 months at IBM T. J. Watson Research Center, he moved to the Swedish Institute of Computer Science (SICS) to form a research lab on logic programming and parallel systems. Dr. Haridi is currently the research director of the Swedish Institute of Computer Science. He has been an active researcher in the area of logic and constraint programming and parallel processing since the beginning of the eighties. His earlier work includes contributions to the design of SICStus Prolog, various parallel Prolog systems and a class of scalable cache-coherent multiprocessors known as Cache-Only Memory Architecture (COMA). During the nineties most of his work focused on the design of multiparadigm programming systems based on Concurrent Constraint Programming (CCP). Currently, he is interested in programming systems and software methodology for distributed and agent-based applications. Peter Van Roy, Ph.D.: He obtained an engineering degree from the Vrije Universiteit Brussel (1983), Masters and Ph.D. degrees from the University of California at Berkeley (1984, 1990), and the Habilitation à Diriger des Recherches from Paris VII Denis Diderot (1996). He has made major contributions to logic language implementation. His research showed for the first time that Prolog can be implemented with the same execution efficiency as C. He was principal developer or codeveloper of Aquarius Prolog, Wild_Life, Logical State Threads, and FractaSketch. He joined the Oz project in 1994 and is currently working on Distributed Oz. His research interests are motivated by the desire to provide increased expressivity and efficiency to application developers. Per Brand: He is a researcher at the Swedish Institute of Computer Science. He has previously worked on the design and implementation of OR-parallel Prolog (the Aurora project) and optimized compilation techniques for Concurrent Constraint Programming Languages (in particular, AKL). He has been a member of the Distributed Oz design team since the project began. His research interests are focused on techniques, languages, and methodology for distributed programming. Christian Schulte: He studied computer science at the University of Karlsruhe, Germany, from 1987 to 1992 where he received his diploma. Since 1992 he has been a member of the Programming Systems Lab at DFKI. He is one of the principal designers of Oz. His research interests include design, implementation, and application of concurrent and distributed programming languages as well as constraint programming.     

A parallel copying garbage collection scheme for shared-memory multiprocessors

Earlier work on parallel copying garbage collection is based on parallelization of sequential schemes with breadth-first traversing of live data. Recently it has been demonstrated that sequential copying schemes with depth-first traversing of live data are more flexible and more efficient than the corresponding ones with breadth-first traversal. A clear advantage of the former is that they work with no extra space overheads on non-contiguous memory blocks, which allows more flexible implementation. This paper shows how to parallelize an efficient depth-first copying scheme while retaining its high efficiency and flexibility. Research interests: His research interests include techniques for parallel and distributed implementation of functional, logic, concurrent constraints and object-oriented programming systems. He is also interested in performance analysis and garbage collection. His current interest is efficient techniques for distributed implementation of the concurrent programming language Oz.     

Generic Pickling and Minimization

This paper presents generic pickling and minimization mechanisms that are provided as services similar to garbage collection. Pickling is used to externalize and internalize data. Minimization means to maximize the sharing in arbitrary data structures. The paper introduces the notion of an abstract store as a formal basis for the algorithms, and analyzes design decisions for the implementation aspects of pickling and minimization. The mechanisms presented here are fully implemented in the Alice programming system.     

Using UML and OCL for representing multiobjective combinatorial optimization problems

This paper describes the results of a preliminary feasibility study of an approach to representing multiobjective combinatorial optimization problems in UML (structural constraints) and OCL (procedural constraints) and then automatically translating the representations to a constraint satisfaction solving language (Oz) for execution. The paper presents two examples of the application of the approach—a job scheduling problem and a (fixture) design problem. The main goal of this paper is to investigate directions towards a standard, graphical language for representing combinatorial optimization problems. The paper shows that for the two selected problems it is easy to represent structural constraints in UML and that procedural constraints are representable in OCL. The results also show that a developed translator automatically converts the UML/OCL representations to Oz and that the resulting Oz program performs very reasonably, in some cases outperforming the hand-written benchmark programs.     

The role of social interaction on users motivation to exercise: A persuasive web framework to enhance the self-management of a healthy lifestyle

The current research guidelines of the European community suggest the importance of the development of systems that help users manage their health themselves. The increasing amount of communication technologies and devices from which users can access information, and the possibility to interact through social media channels, play an important role in this scenario. Based on these considerations, in this paper we present an innovative persuasive web application, designed both to exploit social networking sites and to cooperate with a mobile application that already operates in the e-health and motivational domains. In particular, the innovative aspects introduced by the web application are the possibility to access also from a web browser some features previously available only through a mobile application and a more direct and user-friendly integration of social network sites. Indeed, thanks to an extensive interaction with the Facebook social network, users are allowed to share their experience with the application. This generates a strong social influence effect, which inspires and motivates other users to improve their exercising activity. Experimental results put in evidence that our web application, also thanks to social interactions, is favoring an enhancement of users’ motivation to a more active lifestyle. This is mainly due to its capability to have an impact on the other users thanks to the posts generated on the Facebook social network.     

Pro-active meeting assistants: attention please!

This paper gives an overview of pro-active meeting assistants, what they are and when they can be useful. We explain how to develop such assistants with respect to requirement definitions and elaborate on a set of Wizard of Oz experiments, aiming to find out in which form a meeting assistant should operate to be accepted by participants, and whether the meeting effectiveness and efficiency can be improved by an assistant at all. This paper gives an overview of pro-active meeting assistants, what they are and when they can be useful. We explain how to develop such assistants with respect to requirement definitions and elaborate on a set of Wizard of Oz experiments, aiming to find out in which form a meeting assistant should operate to be accepted by participants, and whether the meeting effectiveness and efficiency can be improved by an assistant at all.     

Assessing the effects of building social intelligence in a robotic interface for the home

This paper reports an exploration of the concept of social intelligence in the context of designing home dialogue systems for an Ambient Intelligence home. It describes a Wizard of Oz experiment involving a robotic interface capable of simulating several human social behaviours. Our results show that endowing a home dialogue system with some social intelligence will: (a) create a positive bias in the user's perception of technology in the home environment, (b) enhance user acceptance for the home dialogue system, and (c) trigger social behaviours by the user in relation to the home dialogue system.     

The Implementation of a Deductive Query Language Over an OODB

The ROCK and ROLL database system cleanly integrates deductive and object-oriented capabilities by defining an imperative programming language, ROCK, and a declarative, deductive language, ROLL, over a common object-oriented (OO) data model. Existing techniques for evaluation and optimization of deductive languages fail to address key requirements imposed by ROLL such as: strict typing; placement of deductive methods (predicates) within classes; encapsulation; overriding and late binding. This paper describes the task of implementing an evaluator and optimizer for ROLL, explaining how existing implementation techniques for deductive languages were adapted to meet these requirements and extended to support novel types of optimization.     

Asymmetric bidirectional controlled remote preparation of an arbitrary four-qubit cluster-type state and a single-qubit state

In this paper, we propose a novel scheme for asymmetric bidirectional controlled remote state preparation (ABCRSP) via a ten-qubit entangled state as the quantum channel. In this scheme, two distant parties, Alice and Bob are not only senders but also receivers, and Alice wants to remotely prepare a single-qubit state at Bob’s site; at the same time, Bob wishes to help Alice remotely prepare an arbitrary four-qubit cluster-type entangled state. It is shown that only if the two senders and the controller collaborate with each other, the ABCRSP can be completed successfully. We demonstrate that the total success probability of the ABCRSP in this scheme can reach 1, that is, the scheme is deterministic.     

Building a Swiss German Sign Language avatar with JASigning and evaluating it among the Deaf community

This paper reports on the development of a system that translates German train announcements of the Swiss Federal Railways (Schweizerische Bundesbahnen, SBB) into Swiss German Sign Language (Deutschschweizerische Gebärdensprache, DSGS) in real time and displays the result via an avatar. The system used to animate the avatar is called JASigning. Deliverables of the projects during which JASigning was developed are the main source of documentation for the system along with notes on the Web site. Not all planned features have been fully implemented: some because they are used very infrequently; others because there is insufficient linguistic research on which to base an implementation. The team of hearing and Deaf researchers identified the avatar functionality needed for the project and built a first version of the avatar. A focus group study with seven Deaf signers was then carried out to obtain feedback on how to further improve the avatar. This paper reports the evaluation results. It also discusses the workarounds introduced for features that were not yet directly available in the JASigning system. These features were not specific to train announcements. Hence, knowledge of how to achieve their designated effects in JASigning can be useful to persons working with other types of sign language data as well.     

一种新型类型化中间语言的优化实现技术

类型化中间语言是提高代码安全性的一类重要方法。然而在其实现过程中,庞大的类型信息很难被高效地表达和操作。一个未经优化的实现将会给系统带来指数级增长的开销。该文描述了一种新型的类型化中间语言的优化实现技术,并将其成功应用于Intel ORP (Open Runtime Platform)的即时编译器中。     

Private predictions on hidden Markov models

Hidden Markov models (HMMs) are widely used in practice to make predictions. They are becoming increasingly popular models as part of prediction systems in finance, marketing, bio-informatics, speech recognition, signal processing, and so on. However, traditional HMMs do not allow people and model owners to generate predictions without disclosing their private information to each other. To address the increasing needs for privacy, this work identifies and studies the private prediction problem; it is demonstrated with the following scenario: Bob has a private HMM, while Alice has a private input; and she wants to use Bob’s model to make a prediction based on her input. However, Alice does not want to disclose her private input to Bob, while Bob wants to prevent Alice from deriving information about his model. How can Alice and Bob perform HMMs-based predictions without violating their privacy? We propose privacy-preserving protocols to produce predictions on HMMs without greatly exposing Bob’s and Alice’s privacy. We then analyze our schemes in terms of accuracy, privacy, and performance. Since they are conflicting goals, due to privacy concerns, it is expected that accuracy or performance might degrade. However, our schemes make it possible for Bob and Alice to produce the same predictions efficiently while preserving their privacy.     

Propagation engine prototyping with a domain specific language

Constraint propagation is at the heart of constraint solvers. Two main trends co-exist for its implementation: variable-oriented propagation engines and constraint-oriented propagation engines. Those two approaches ensure the same level of local consistency but their efficiency (computation time) can be quite different depending on the instance solved. However, it is usually accepted that there is no best approach in general, and modern constraint solvers implement only one. In this paper, we would like to go a step further providing a solver independent language at the modeling stage to enable the design of propagation engines. We validate our proposal with a reference implementation based on the Choco solver and the MiniZinc constraint modeling language.     

Translating a Linear Logic Programming Language into Java

There have been several proposals for logic programming language based on linear logic: Lolli [8], Lygon [7], LO [3], LinLog [2], Forum [11], HACL [10]. In these languages, it is possible to create and consume resources dynamically as logical formulas. The efficient handling of resource formulas is, therefore, an important issue in the implementation of these languages. Lolli, Lygon, and Forum are implemented as interpreter systems; Lolli is on SML and λProlog, Lygon is on Prolog, Forum is on SML, λProlog and Prolog. However, none of them have been implemented in Java.In this paper, we describe the Prolog Café ¹ system which translates a linear logic programming language called LLP to Java via the LLPAM [12] [5], an extension of the standard WAM [16] [1] for LLP. LLP is a superset of Prolog and a subset of Lolli. The main difference from the first implementation [4] is resource compilation. That is to say, resource formulas are compiled into closures which consist of a reference of compiled code and a set of bindings for free variables. Calling these resources is integrated with the ordinary predicate invocation.Prolog Café is portable to any platform supporting Java and easily expandable with increasing Java's class libraries. In performance, on average, Prolog Café generate 2.2 times faster code for a set of classical Prolog benchmarks compared with jProlog.     

A simple algorithm for clock synchronization in transputer networks

In a distributed system based on Transputer components there is one clock for each processing element, and the definition of the global system time requires the choice of a hardware or software synchronization method. This paper describes the RING_SYNC algorithm, based on a ring-structured synchronization scheme. RING_SYNC has no provision for fault tolerance, but it introduces little overhead, thanks to the optimization of both the number of messages exchanged at sync time and the resynchronization frequency. The implementation of the algorithm together with the tests performed for measuring the synchronization error and their results are discussed extensively, and some typical applications are pointed out.