Self-adapting recovery nets for policy-driven exception handling in business processes

In this paper, we propose Self-Adapting Recovery Net (SARN), an extended Petri net model, for specifying exceptional behavior in business processes. SARN adapts the structure of the underlying Petri net at run time to handle exceptions while keeping the Petri net design easy. The proposed framework caters for the specification of high-level recovery policies that are incorporated either with a single task or a set of tasks, called a Recovery Region. These recovery policies are generic directives that model exceptions at design time together with a set of primitive operations used at run time to handle the occurrence of exceptions. We identified a set of recovery policies that are useful and commonly needed in many practical situations. A tool has been developed to illustrate the viability of the proposed exception handling technique. B. Medjahed’s work is supported by a grant from the University of Michigan’s OVPR.     

A knowledge-based approach for handling exceptions in business processes

This paper describes a novel knowledge-based methodology and toolset for helping business process designers and participants better manage exceptions (unexpected deviations from an ideal sequence of events caused by design errors, resource failures, requirement changes, etc.) that can occur during the enactment of a process. This approach is based on an on-line repository exploiting a generic and reusable body of knowledge, which describes what kinds of exceptions can occur in collaborative work processes, how these exceptions can be detected, and how they can be resolved. This work builds upon previous efforts from the MIT Process Handbook project and from research on conflict management in collaborative design. This revised version was published online in July 2006 with corrections to the Cover Date.     

A lightweight and proactive rule-based incremental construction approach to detect phishing scam

The development of digitization over the globe has made digital security inescapable. As every single article on this planet is being digitalized quickly, it is more important to protect those items. Numerous cyber threats effectively deceive ordinary individuals to take away their identifications. Phishing is a kind of social engineering attack where the hackers are using this kind of attack in modern days to steal the user's credentials. After a systematic research analysis of phishing technique and email scam, an intrusion detection system in chrome extension is developed. This technique is used to detect real-time phishing by examining the URL, domain, content and page attributes of an URL prevailing in an email and any web page portion. Considering the reliability, robustness and scalability of an efficient phishing detection system, we designed a lightweight and proactive rule-based incremental construction approach to detect any unknown phishing URLs. Due to the computational intelligence and nondependent of the blacklist signatures, this application can detect the zero-day and spear phishing attacks with a detection rate of 89.12% and 76.2%, respectively. The true positive values acquired in our method is 97.13% and it shows less than 1.5% of false positive values. Thus the application shows the precision level higher than the previous model developed and other phishing techniques. The overall results indicate that our framework outperforms the existing method in identifying phishing URLs.

     

Context aware exception handling in business process execution language

ContextFault handling represents a very important aspect of business process functioning. However, fault handling has thus far been solved statically, requiring the definition of fault handlers and handling logic to be defined at design time, which requires a great deal of effort, is error-prone and relatively difficult to maintain and extend. It is sometimes even impossible to define all fault handlers at design time.ObjectiveTo address this issue, we describe a novel context-aware architecture for fault handling in executable business process, which enables dynamic fault handling during business process execution.MethodWe performed analysis of existing fault handling disadvantages of WS-BPEL. We designed the artifact which complements existing statically defined fault handling in such a way that faults can be defined dynamically during business process run-time. We evaluated the artifact with analysis of system performance and performed a comparison against a set of well known workflow exception handling patterns.ResultsWe designed an artifact, that comprises an Observer component, Exception Handler Bus, Exception Knowledge Base and Solution Repository. A system performance analysis shows a significantly decreased repair time with the use of context aware activities. We proved that the designed artifact extends the range of supported workflow exception handling patterns.ConclusionThe artifact presented in this research considerably improves static fault handling, as it enables the dynamic fault resolution of semantically similar faults with continuous enhancement of fault handling in run-time. It also results in broader support of workflow exception handling patterns.     

A meta modeling approach to workflow management systems supporting exception handling

Workflow Management Systems (WFMSs) facilitate the definition of structure and decomposition of business processes and assists in management of coordinating, scheduling, executing and monitoring of such activities. Most of the current WFMSs are built on traditional relational database systems and/or using an object-oriented database system for storing the definition and run time data about the workflows. However, a WFMS requires advanced modeling functionalities to support adaptive features, such as on-line exception handling. This article describes our advanced meta-modeling approach using various enabling technologies (such as object orientation, roles, rules, active capabilities) supported by an integrated environment, the ADOME, as a solid basis for a flexible WFMS involving dynamic match making, migrating workflows and exception handling.     

一种规则驱动的Web服务组合例外处理方法

提出一种规则驱动的Web服务组合例外处理模型,并对该模型的语义进行了详细说明。模型中的规则基于事件、状态以及元流程。元流程由相应的规则启动,并对基础流程进行协调和控制。该方法不仅支持错误恢复,同时也支持流程修改等复杂状况。模型实现了服务组合例外处理的模块化、可扩展性以及适应性。     

一种异常处理机制的设计与实现

异常处理是一种用来检测异常并时其进行处理的技术。异常处理机制已作为现代程序设计语言的一个重要的特性被广泛地采纳,以增强系统运行的可靠性,提高软件的健壮性。对异常处理在程序语言的实现进行了一般性研究,分析比较几种异常处理机制及其实现方法,提出了一种新的异常处理机制的实现方法。     

测试Java异常处理机制的方法

异常处理机制能增强程序运行的可靠性,提高软件的健壮性.然而,如果异常处理机制使用不当,会带来许多潜在的错误,因而很有必要对程序的异常处理结构进行测试.提出了一种识别被测程序中的所有异常变量"定义-使用"关系的方法,并使用一个异常的定义-捕获度量来计算异常定义-使用链的测试覆盖.最后设计了一种异常分析及测试的原型工具.     

An approach to capture authorisation requirements in business processes

Business process modelling focuses on the modelling of functional behaviour. In this article, we propose an extension for the business process modelling notation to express non-functional authorisations requirements in a process model to enable the collaboration between security experts and business analysts. To capture multi-level, role-based and Separation of Duty authorisation requirements, new model element attributes and authorisation artefacts are introduced. To enhance the usability of this approach, simple visual decorators are specified to ease the communication of requirements between various stakeholders. To provide an early validation of these authorisation requirements during the definition of a process model, formal semantics are applied to the process model and model-checking techniques are used to provide feedback. As a pragmatic proof-of-concepts, a first prototype implementation is briefly discussed.     

Real-time risk monitoring in business processes: A sensor-based approach

This article proposes an approach for real-time monitoring of risks in executable business process models. The approach considers risks in all phases of the business process management lifecycle, from process design, where risks are defined on top of process models, through to process diagnosis, where risks are detected during process execution. The approach has been realized via a distributed, sensor-based architecture. At design-time, sensors are defined to specify risk conditions which when fulfilled, are a likely indicator of negative process states (faults) to eventuate. Both historical and current process execution data can be used to compose such conditions. At run-time, each sensor independently notifies a sensor manager when a risk is detected. In turn, the sensor manager interacts with the monitoring component of a business process management system to prompt the results to process administrators who may take remedial actions. The proposed architecture has been implemented on top of the YAWL system, and evaluated through performance measurements and usability tests with students. The results show that risk conditions can be computed efficiently and that the approach is perceived as useful by the participants in the tests.     

Static analysis of exception handling in Ada

Since the signature of an Ada subprogram does not specify the set of exceptions that the subprogram can propagate, computing the set of exceptions that a subprogram may encounter is not a trivial task. This is a source of error in large Ada systems: for example, a subprogram may not be prepared to handle an exception propagated from another subprogram several layers lower in the call-tree. In a large system, the number of paths in exceptional processing is so great that it is unlikely that testing will uncover all errors in inter-procedural exception handling. Nor are compilers or code inspections likely to locate all such errors. Exception handling is an area where static analysis has a high potential payoff for systems with high reliability requirements. We discuss fundamental notions in computing exception propagation and describe an analysis tool that has proved to be effective in detecting inconsistencies in the exception-handling code of Ada applications.     

A mechanism for exception handling and its verification rules

This paper presents a control structure designed for an exception handling mechanism based on Goodenough's proposal. The aim is to provide a recovery mechanism as a basic component of any procedure-oriented language, which can handle any kind of error, ranging from design errors to occasional malfunctioning of hardware components.The semantics of the structure is described formally by means of Hoare type verification rules.     

Uncertainty handling in rule-based mobile context-aware systems

Uncertainty handling is one of the most important aspects of modelling of context-aware systems. It has direct impact on the adaptability, understood as an ability of the system to adjust to changing environmental conditions or hardware configuration (missing data), changing user habits (ambiguous concepts), or imperfect information (low quality sensors). In mobile context-aware systems, data is most often acquired from device’s hardware sensors (like GPS, accelerometer), virtual sensors (like activity recognition sensor provided by the Google API) or directly from the user. Uncertainty of such data is inevitable, and therefore it is obligatory to provide mechanisms for modelling and processing it. In this paper, we propose three complementary methods for dealing with most common uncertainty types present in mobile context-aware systems. We combine modified certainty factors algebra, probabilistic interpretation of rule-based model, and time-parametrised operators into a comprehensive toolkit for modelling and building robust mobile context-aware systems. Presented approach was implemented and evaluated on the practical use-case.     

A proactive material handling method for CPS enabled shop-floor

Cyber physical system (CPS) enables companies to keep high traceability and controllability in manufacturing for better quality and improved productivity. However, several challenges including excessively long waiting time and a serious waste of energy still exist on the shop-floor where limited buffer exists for each machine (e.g., shop-floor that manufactures large-size products). The production logistics tasks are released after work-in-processes (WIPs) are processed, and the machines will be occupied before trolleys arrival when using passive material handling strategy. To address this issue, a proactive material handling method for CPS enabled shop-floor (CPS-PMH) is proposed. Firstly, the manufacturing resources (machines and trolleys) are made smart by applying CPS technologies so that they are able to sense, act, interact and behave within a smart environment. Secondly, a shop-floor digital twin model is created, aiming to reflect their status just like real-life objects, and key production performance indicators can be analysed timely. Then, a time-weighted multiple linear regression method (TWMLR) is proposed to forecast the remaining processing time of WIPs. A proactive material handling model is designed to allocate smart trolleys optimally. Finally, a case study from Southern China is used to validate the proposed method and results show that the proposed CPS-PMH can largely reduce the total non-value-added energy consumption of manufacturing resources and optimize the routes of smart trolleys.     

Java虚拟机中异常机制实时性的研究及实现

异常处理机制是程序设计语言的重要特征之一。讨论了对Java异常处理进行实时性改造的可行性和具体方法,并且在Linux平台上,实现了对开源Java虚拟机SableVM中异常处理机制的实时性改造。实验结果表明改进后的虚拟机在异常捕获时间趋于线性的同时,异常表查询效率也得到了提高。     

The measurement of information technology absorption into information handling processes in business

The need for a comparative measure of information technology absorption in business is discussed. Studies of various forms of technological change are reviewed in terms of three issues; the level of measurement used, the research techniques/methods used and the approaches to the measurement of technology absorption. The requisite properties for an assessment of information technology absorption within business are outlined. A framework for a structured interview schedule is proposed which could assess approaches to information handling at several levels of analysis (e.g. departments, sites, organizations, industries). A pilot factor analysis of the IT items within the schedule across a sample of businesses reveals a sensible three-factor structure of IT influence within information handling. This form of measure is shown to offer sufficient sensitivity to assess technological changes within organizations and be relatable to behavioural outcomes. The extent of changes in management roles is shown to be correlated with degree of IT change along the three dimensions identified. The needs for further research are discussed.     

An autonomic approach to manage elasticity of business processes in the Cloud

Cloud Computing is gaining more and more importance in the Information Technologies (IT) scope. One of the major assets of this paradigm is its economic model based on pay-as-you-go model. Cloud Computing gets more attention from IT users when it fits their required QoS and reduces their expenses. This task cannot be done without increasing the autonomy of the provisioned Cloud resources. In this paper, we propose a holistic approach that allows to dynamically adding autonomic management facilities to Cloud resources even if they were designed without these facilities. Based on the Open Cloud Computing Interface (OCCI) standard, we propose a generic model that allows describing the needed resources to render autonomic a given Cloud resource independently of the service level (Infrastructure, Platform or Software). Herein, we define new OCCI Resources, Links and Mixins that allow provisioning autonomic Cloud Resources. In order to illustrate our approach, we propose a use case that specializes our autonomic infrastructure to ensure the elasticity of Service-based Business Processes (SBPs). The elasticity approach that we are using is based on a formal model that features duplication/consolidation mechanisms and a generic Controller that defines and evaluates elasticity strategies. To validate our proposal, we present an end to end scenario of provisioning an elastic SBP on a public PaaS. Evaluation of our approach on a realistic situation shows its efficiency.