A middleware to support services delivery in a domain-specific virtual machine

The increasing use of model-driven software development has renewed emphasis on using domain-specific models during application development. More specifically, there has been emphasis on using domain-specific modeling languages (DSMLs) to capture user-specified requirements when creating applications. The current approach to realizing these applications is to translate DSML models into source code using several model-to-model and model-to-code transformations. This approach is still dependent on the underlying source code representation and only raises the level of abstraction during development. Experience has shown that developers will many times be required to manually modify the generated source code, which can be error-prone and time consuming. ^ An alternative to the aforementioned approach involves using an interpreted domain-specific modeling language (i-DSML) whose models can be directly executed using a Domain Specific Virtual Machine (DSVM). Direct execution of i-DSML models require a semantically rich platform that reduces the gap between the application models and the underlying services required to realize the application. One layer in this platform is the domain-specific middleware that is responsible for the management and delivery of services in the specific domain. ^ In this dissertation, we investigated the problem of designing the domain-specific middleware of the DSVM to facilitate the bifurcation of the semantics of the domain and the model of execution (MoE) while supporting runtime adaptation and validation. We approached our investigation by seeking solutions to the following sub-problems: (1) How can the domain-specific knowledge (DSK) semantics be separated from the MoE for a given domain? (2) How do we define a generic model of execution (GMoE) of the middleware so that it is adaptable and realizes DSK operations to support delivery of services? (3) How do we validate the realization of DSK operations at runtime? ^ Our research into the domain-specific middleware was done using an i-DSML for the user-centric communication domain, Communication Modeling Language (CML), and for microgrid energy management domain, Microgrid Modeling Language (MGridML). We have successfully developed a methodology to separate the DSK and GMoE of the middleware of a DSVM that supports specialization for a given domain, and is able to perform adaptation and validation at runtime. ^

A follow-up outcome evaluation of independent living services for foster care youth

This study aimed to evaluate the effectiveness of the Independent Living (IL) program targeting foster youths to prepare them for effective adulthood. The study employed a pre-post, two-group comparative research design. The IL group was composed of 49 young adults who participated in the IL or SIL (subsidized IL) program prior to their emancipation from foster care (mean age, 20.6 years). The comparison was made up of 18 young adults who experienced foster care but never participated in the IL or SIL programs (mean age, 20.2 years). Data were collected via a mailed survey that included the Daniel Memorial Independent Living Assessment (DMILA) and an additional questionnaire developed by the researcher. The study also examined: (1) why youth in foster care do not participate in IL programs, (2) how participating youth evaluate IL services and what recommendations they make to improve services, and (3) the internal consistency of the DMILA. Results suggest that the DMILA assessment has mediocre reliability. IL program participation is associated with better educational, employment, income, housing, early parenting-prevention, transportation, anger control, criminal-prevention, and self-evaluation outcomes. However, IL participation is not associated with better social support, perceived parenting competence, substance abuse-prevention, sexual risk-prevention outcomes, increased knowledge in money management skills, job seeking and job maintenance skills, interpersonal skills, or lower depression. Results also suggest that the outreach activities of the IL program may be flawed. IL participants reported the IL program was doing best in educational preparation, criminal involvement prevention, and money management preparation and least well in parenting preparation, housing preparation, employment preparation, and substance abuse prevention. To improve services, youths recommended primarily that IL counselors develop closer relationships with youths, that IL training better address organizational skills, and that monthly subsidy be raised and SIL eligibility requirements softened. The study's political context and limitations are also discussed and implications are derived regarding prevention, intervention, outreach, mentorship, empowerment, cross-systems collaboration, and future research. ^

Enabling adaptability in service aggregates using transparent shaping techniques

Distributed applications are exposed as reusable components that are dynamically discovered and integrated to create new applications. These new applications, in the form of aggregate services, are vulnerable to failure due to the autonomous and distributed nature of their integrated components. This vulnerability creates the need for adaptability in aggregate services. The need for adaptation is accentuated for complex long-running applications as is found in scientific Grid computing, where distributed computing nodes may participate to solve computation and data-intensive problems. Such applications integrate services for coordinated problem solving in areas such as Bioinformatics. For such applications, when a constituent service fails, the application fails, even though there are other nodes that can substitute for the failed service. This concern is not addressed in the specification of high-level composition languages such as that of the Business Process Execution Language (BPEL). We propose an approach to transparently autonomizing existing BPEL processes in order to make them modifiable at runtime and more resilient to the failures in their execution environment. By transparent introduction of adaptive behavior, adaptation preserves the original business logic of the aggregate service and does not tangle the code for adaptive behavior with that of the aggregate service. The major contributions of this dissertation are: first, we assessed the effectiveness of BPEL language support in developing adaptive mechanisms. As a result, we identified the strengths and limitations of BPEL and came up with strategies to address those limitations. Second, we developed a technique to enhance existing BPEL processes transparently in order to support dynamic adaptation. We proposed a framework which uses transparent shaping and generative programming to make BPEL processes adaptive. Third, we developed a technique to dynamically discover and bind to substitute services. Our technique was evaluated and the result showed that dynamic utilization of components improves the flexibility of adaptive BPEL processes. Fourth, we developed an extensible policy-based technique to specify how to handle exceptional behavior. We developed a generic component that introduces adaptive behavior for multiple BPEL processes. Fifth, we identify ways to apply our work to facilitate adaptability in composite Grid services.

Biometrics for Hospitality and Tourism: A New Wave of Information Technology

The technologies that empower biometrics have been around for a number of years, but until recently these technologies have been viewed as exotic. In the not too distant future biometrics will be used to regulate internal processes and to improve services in the hospitality and tourism industries. This paper provides an understanding of the current use of biometrics in general and its practical value for the future in hospitality and tourism. The study presents a review of current practices of biometrics with special reference to the hospitality and tourism businesses, addresses key issues imposed by this technology, and identifies business and marketing implications for these industries.