Service Workflow Research Articles

Spanning Web Capabilities over Clouds

As developers interleave Web capabilities across cloud infrastructures, deploying service workflows will introduce a number of challenges. Here, Brian Blake poses questions that must be considered to meet such challenges.

Integration of data and computing infrastructures for earth science: an image mosaicking use-case

This paper addresses the emerging issue of integrating data sharing and computing e-infrastructures for multidisciplinary applications. In the recent years several solutions have been proposed to implement digital infrastructures for sharing and processing scientific data and observations. Spatial data infrastructures currently enable effective and efficient geo-information data sharing in many disciplinary communities, and innovative solutions are under development to support new open data and linked data paradigms. In parallel, High Performance Computing systems, computing grids and more recently cloud services, enable fast processing of big data. However, the integration of data and computing e-infrastructures is a raising issue in multidisciplinary research. In the context of the Global Earth Observation System of Systems (GEOSS) initiative, an innovative approach has been proposed. Taking into account that the heterogeneity of data and computing e-infrastructures and related technologies cannot be reduced beyond a certain extent, since it is due to the need of supporting use cases and scenarios from different scientific communities, a brokering solution has been designed and developed. A Business Process Broker (BPB) is a component which takes a formal description of a scientific business process, and translates it in an executable process which can be run on multiple and remote processing and workflow services. In doing this it solves all the interoperability issues in a (semi-)automated way. It allows lowering the entry barrier for both computing service providers and users, decoupling the specification of the scientific process from the underlying enabling infrastructures. The paper presents and discusses a BPB use-case from the European project IASON, implementing an Earth Observation application involving satellite image mosaicking, HPC computing services and spatial data e-infrastructures.

Multi-criteria selection for services selection in service workflow

Selecting services to be part of a workflow has been a very important challenge. As a number of available services increases, the selection becomes more complicated. Different providers may offer the same service with different non-functional attributes such as services’ qualities, past experience, reputation value, etc. Moreover, the importance of each attribute is subjective and varies in different contexts of use. Complexity increases due to dynamic changes in real-time service workflow interoperation, for example, services can dynamically join or leave at any time, attributes can be changed, or the importance of an attribute can be lessened or increased. To alleviate this problem, this paper presents a Multi-Criteria Decision Making (MCDM) approach for dynamic real-time service selection in service workflow. The main study emphasizes on an integrated architecture with the enhancement of compliance checking for Service Workflow Specification language (SWSpec) with MCDM using Analytic Hierarchy Process (AHP). This approach enables real-time service selection based on the degree of compliance, in which depending on each context the best-suited services can be determined. To make this approach more understandable, an application example of car rental agent is demonstrated.

Modeling method for integration of air command and security process

Air command and security (ACS) process is a kind of typical complex operation process. Its modeling issue has become a hot spot and challenge in the research field of complex operation process. Combining the demand on the application of air command and support, this paper proposes a simulation-based modeling method of integrating air command and support process, emphatically describing such aspects as the meta-model of the concept of aviation support process, work flow service modeling and arrangement of multi-aircraft process, etc. Finally, based on actual cases of application, this paper unfolds simulating verification and assessment on the whole process of control and support operation process of a flight task involving multiple aircrafts.

Building scalable, secure, multi-tenant cloud services on IBM Bluemix

While an infrastructure-as-a-service cloud provides an economic alternative to managing information technology on premises, it does not provide ready-to-use advanced functionalities for solution management. A platform-as-a-service cloud (PaaS), on the other hand, provides application management and offers a catalog of services, which developers can easily use to host their solutions in the cloud. It also provides DevOps capabilities, which facilitate the management of a solution lifecycle. In this paper, we offer insights into the benefits and challenges that developers, who want to develop applications or offer services, would face in using a PaaS. We describe the step-by-step process of developing applications and offering services on IBM Bluemix, which is a PaaS cloud. We identify the key ingredients to achieve service scalability, security, and multi-tenancy. We also demonstrate the entire process through case studies of two Bluemix services: Rating-as-a-Service (RaaS) and the beta release of the Workflow Service .

Composition of Resource-Service Chain for Cloud Manufacturing

In distributed manufacturing systems, manufacturing resource composition is one of the most important problems. This is because efficiency of resource selection and resource utilization can all be improved if it is tackled well. However, most of the existing methods neglect temporal relationship between resources. This leads to an inefficient use of resources, because all resources have to be kept available before a business process is started. A temporal composition of resources is more suitable, as it expresses the scheduling and the flow of servicing to a business process. Therefore, resource services invoked in sequential order are called the resource-service chain (RSC), in view that distributed resources are encapsulated into cloud services in a cloud manufacturing (CMfg) environment. We propose an approach, called RSC composition algorithm (RSCCA) that can better cope with the temporal relationship between the resource services in a business process. Specifically, a two-stage composition method based on the degrees of dependency between resource services in workflow is proposed. To begin, in the build-time stage algorithm, RSCCA resolves initial compositions based on task relatedness and temporal dependencies between resource services, and then calculates the usage frequencies of ICs by mining workflow log at workflow runtime stage. Based on this, RSCCA can compose individual resource services as more than sets, especially as chains, allowing flow directions and dynamics to be considered. RSCCA has been tested with different data sets and the results show that it can be very promising.

SLMToolBox: enterprise service process modelling and simulation by coupling DEVS and services workflow

Market competition is pushing companies to differentiate themselves from competitors by developing customised services in addition to their original production (either physical or digital). It drives the emergence of service process modelling to describe precisely the composition of services. To this end, this paper presents the key concept of the transformation of EA* and BPMN models into simulation workflows. Then, it introduces the implementation done with the SLMToolBox that is a service graphical modeller, model transformer, and simulation engine. In addition, enterprises are facing situations where future (undeveloped yet) enterprise services need to be integrated with existing ones. To go further and for a better integration and deployment of service models in the enterprise, we propose to combine service process M&S with service calls execution workflow. To achieve that goal, we are mashing up simulation of services modelled with existing enterprise web services calls.

SLMToolBox: enterprise service process modelling and simulation by coupling DEVS and services workflow

SLMToolBox: enterprise service process modelling and simulation by coupling DEVS and services workflow

A Petri Net Method for Compatibility Enforcement to Support Service Choreography

Non-local choice mismatch is one of the most important problems in the Internet-scale and service-based workflow ecosystems. The state-of-the-art method can solve it by generating adaptors to check deadlock-freeness based on a reachability graph. The states in the reachability graph give clues to re-design the composition. Deadlocks are resolved via an iterative process. However, this method is inefficient due to the overlook of the future deadlock state and the requirement of many interactions with a developer. In this paper, an abnormity prevention strategy based on an optimal controller is proposed for collaboration services described by Web Services Choreography Description Language. To overcome the deficiencies of the previous work, we describe service choreography by using service workflow nets. Then, by combining structure and reachability analyses, we formulate a different reachability graph called controlled reduced one. We next develop a maximally permissive state feedback control policy to prevent abnormity. We finally construct an optimal controller for the administrator of service composition to avoid deadlocks in service choreography. The advantage of our methodology is verified via an example.

Monetary Cost Optimizations for Hosting Workflow-as-a-Service in IaaS Clouds

Recently, we have witnessed workflows from science and other data-intensive applications emerging on Infrastructure-asa-Service (IaaS) clouds, and many workflow service providers offering workflow as a service (WaaS). The major concern of WaaS providers is to minimize the monetary cost of executing workflows in the IaaS cloud. While there have been previous studies on this concern, most of them assume static task execution time and static pricing scheme, and have the QoS notion of satisfying a deterministic deadline. However, cloud environment is dynamic, with performance dynamics caused by the interference from concurrent executions and price dynamics like spot prices offered by Amazon EC2. Therefore, we argue that WaaS providers should have the notion of offering probabilistic performance guarantees for individual workflows on IaaS clouds. We develop a probabilistic scheduling framework called Dyna to minimize the monetary cost while offering probabilistic deadline guarantees. The framework includes an A*-based instance configuration method for performance dynamics, and a hybrid instance configuration refinement for utilizing spot instances. Experimental results with three real-world scientific workflow applications on Amazon EC2 demonstrate (1) the accuracy of our framework on satisfying the probabilistic deadline guarantees required by the users; (2) the effectiveness of our framework on reducing monetary cost in comparison with the existing approaches.

Enhanced reproducibility of SADI web service workflows with Galaxy and Docker.

BackgroundSemantic Web technologies have been widely applied in the life sciences, for example by data providers such as OpenLifeData and through web services frameworks such as SADI. The recently reported OpenLifeData2SADI project offers access to the vast OpenLifeData data store through SADI services.FindingsThis article describes how to merge data retrieved from OpenLifeData2SADI with other SADI services using the Galaxy bioinformatics analysis platform, thus making this semantic data more amenable to complex analyses. This is demonstrated using a working example, which is made distributable and reproducible through a Docker image that includes SADI tools, along with the data and workflows that constitute the demonstration.ConclusionsThe combination of Galaxy and Docker offers a solution for faithfully reproducing and sharing complex data retrieval and analysis workflows based on the SADI Semantic web service design patterns.

A service components pipeline model based on multi-source data extraction

Different with the traditional scientific data (such as physics, materials, weather, etc.). The model focuses on the application data source and proposes a service components pipeline model based on multi-source data extaction. Some questions should be considered:firstly, the data modes are not uniformed and metadata representations are difficult to build uniformly, etc. In the service component publishing process, we build an open multi-source data extraction and service data package model for the transparent access to multi-source data service. Secondly, in order to avoid the potential bottlenecks and conflicts(structural conflicts and data collision) in various service components workflow, we dynamically predict the pipeline bottlenecks, analyze the potential structural conflict and data collision among service components and construct the specific-domain component pipeline service model by monitoring trends in data throughput capacity. In the verification process, the model takes ethnic minorities featured villages GIS service workflow (involving national architectural data, ecological data and national costumes data) as an application use case to further verify the methods effectiveness we proposed.

Evolving Technical Services Workflows in a Demand-Driven Acquisitions Pilot

Demand-driven acquisitions (DDA) of electronic books (ebooks) has been a favored method of acquisitions in academic libraries for a number of years. Despite careful consideration and planning ahead of implementation, snags and hiccups may erupt in the acquisitions and cataloging workflow while executing a DDA pilot. Technical Services must remain attentive, collaborative, and flexible in order to redress known issues and anticipate potential ones. DDA is ultimately a worthwhile endeavor that has the potential to replace traditional bibliographer ebook title selection, particularly when the long-term integrity of a collections budget is in question.

A Subsumption Hierarchy of Test Case Prioritization for Composite Services

Many composite workflow services utilize non-imperative XML technologies such as WSDL, XPath, XML schema, and XML messages. Regression testing should assure the services against regression faults that appear in both the workflows and these artifacts. In this paper, we propose a refinement-oriented level-exploration strategy and a multilevel coverage model that captures progressively the coverage of different types of artifacts by the test cases. We show that by using them, the test case prioritization techniques initialized on top of existing greedy-based test case prioritization strategy form a subsumption hierarchy such that a technique can produce more test suite permutations than a technique that subsumes it. Our experimental study of a model instance shows that a technique generally achieves a higher fault detection rate than a subsumed technique, which validates that the proposed hierarchy and model have the potential to improve the cost-effectiveness of test case prioritization techniques.

English

English

Cost Effective Design of an RFID Based Healthcare Service System

Healthcare industry confronts many challenges in a pursuit to give safe, cost-effective and highly-valued healthcare services; Radio Frequency Identification (RFID) is considered as one of the rising mechanism which helps in addressing the challenges, currently faced by Mobile Healthcare Service System (MHS). This article focuses on the contribution of cost-effective RFID deployments in healthcare sector that broadly categorize tracking of items, patients and items associated to patient; providing solutions for improving the auditability and accountability, reducing human errors, eliminating the risks of misidentification, identifying treatment errors and keeping the inventory updated. It explores certain parameters that can play an important role for the cost effective deployment of an RFID system such as security and privacy concerns, social and ethical aspects. Moreover, the article analyses the main challenges faced and investigates how security threats and vulnerabilities are a red flag to RFID technology. Furthermore, different solutions are highlighted that can streamline the operation and can optimize the workflow services in healthcare system. RFID represents next-generation enhancement over bar-code technology. Based on performance evaluation and comparison, differences between the two technologies are identified. This article also provides an overview that how RFID is a key enabler to build-up the healthcare service system and an efficacious affirm in optimizing and transforming healthcare practices.

Research of the Combination of Distributed Business Processes Based on Dynamic Planning

In order to achieve the collaborative completion of entire business process by composition between different workflow management systems, a process composition method based on dynamic programming has been put forward. By analyzing differences and relations between process composition and Web services composition, many aspects have been analyzed with regard to service interface of the workflow system, the interaction control between the workflow systems, parameters and message’s delivery and the planning indexes according to the characteristics of process interaction among the distributed workflow systems. When the process is running, according to the indicators and expectations of users, the optimal workflow services and sub-processes would be selected through dynamic planning method, to provide support to the dynamic combination of workflow processes in a distributed environment.

Informatics solutions for bridging the gap between clinical and laboratory services in a low-resource setting.

There has been little formal analysis of laboratory systems in resource-limited settings, despite widespread consensus around the importance of a strong laboratory infrastructure. This study details the informational challenges faced by the laboratory at Kamuzu Central Hospital, a tertiary health facility in Malawi; and proposes ways in which informatics can bolster the efficiency and role of low-resource laboratory systems. We evaluated previously-collected data on three different aspects of laboratory use. A four-week quality audit of laboratory test orders quantified challenges associated with collecting viable specimens for testing. Data on tests run by the laboratory over a one-year period described the magnitude of the demand for laboratory services. Descriptive information about the laboratory workflow identified informational process breakdowns in the pre-analytical and post-analytical phases and was paired with a 24-hour sample of laboratory data on results reporting. The laboratory conducted 242 242 tests over a 12-month period. The four-week quality audit identified 54% of samples as untestable. Prohibitive paperwork errors were identified in 16% of samples. Laboratory service workflows indicated a potential process breakdown in sample transport and results reporting resulting from the lack of assignment of these tasks to any specific employee cadre. The study of result reporting time showed a mean of almost six hours, with significant variation. This analysis identified challenges in each phase of laboratory testing. Informatics could improve the management of this information by streamlining test ordering and the communication of test orders to the laboratory and results back to the ordering physician.

Research of the Interconnection of Workflow System Based on Web Service

In order to achieve the interconnection between different workflow management systems, it was proposed that all the distributed workflow systems would be encapsulated as web services to perform the entire business process collaboratively by the way of processes’ composition in this paper. By analyzing the comparison between the composition of processes and ordinary Web service, we studied interactive control, the parameters required to be passed through the distributed workflow systems, the workflow system service’s interfaces and its packaging. Furthermore we put forward a general method of the workflow systems interactive interfaces’ extension and the way of the workflow service’s encapsulating and invoking. By this approach, it can easily combine the processes or process fragments which deployed on different workflow systems without other agents and components. It also provides support for the interconnection of the workflow systems in distributed environment, and ultimately achieves a coordinated operation between different workflow engines.

An adaptable navigation strategy for Virtual Microscopy from mobile platforms

Real integration of Virtual Microscopy with the pathologist service workflow requires the design of adaptable strategies for any hospital service to interact with a set of Whole Slide Images. Nowadays, mobile devices have the actual potential of supporting an online pervasive network of specialists working together. However, such devices are still very limited. This article introduces a novel highly adaptable strategy for streaming and visualizing WSI from mobile devices. The presented approach effectively exploits and extends the granularity of the JPEG2000 standard and integrates it with different strategies to achieve a lossless, loosely-coupled, decoder and platform independent implementation, adaptable to any interaction model. The performance was evaluated by two expert pathologists interacting with a set of 20 virtual slides. The method efficiently uses the available device resources: the memory usage did not exceed a 7% of the device capacity while the decoding times were smaller than the 200ms per Region of Interest, i.e., a window of 256×256pixels. This model is easily adaptable to other medical imaging scenarios.