The literature in reading comprehension has demonstrated that both domain-specific knowledge and strategic knowledge are vital to good comprehension. However, few studies have actually compared the effects of the two types of knowledge on reading comprehension. Fewer studies have examined the effects of combining the two strategies even though cognitive theories indicate that true comprehension occurs when certain procedures act upon knowledge constructed from the text being read and "link" that knowledge with knowledge in the long-term memory. This study compared subjects receiving strategic knowledge and content knowledge to subjects receiving strategic knowledge only, subjects receiving content-knowledge only, and a control group. Subjects were 9- and 10-year-old students in four fourth-grade classrooms. The design was a pretest-posttest quasi-experimental design. Subjects were given the comprehension and verbal subtests of the Stanford Achievement Test. Based on these tests, subjects were identified as high- or low-ability readers. In addition, they were given a comprehension pretest designed by the instructor before intervention began. The intervention took place over a 4-week period and consisted of a different series of lessons presented by an independent instructor. After the intervention, subjects took the posttest. SAT subtest scores and pretest scores were used as covariates in the final analysis. Results showed a decrease in the posttest means and no differences among the four experimental groups. Lack of findings was attributed to several factors, including lack of interest in the reading material on the comprehension tests and brevity of the intervention.

Domain-specific languages can significantly speed up the development of software applications. However, it usually takes a few iterations of the language design before it achieves such power. At the same time, many domains tend to evolve quite often today, which implies that domain-specific languages have to evolve accordingly. Thus, being able to evolve a language in a painless manner is crucial. Unfortunately, current state-of-the-art research does not provide enough answers on how to efficiently evolve domain-specific languages. We present an approach to evolving a language in order to reduce the amount of code cloning it introduces. The approach specifically targets those languages whose design causes users to create many duplicated code segments. We target domain-specific languages as they tend to be more challenging to evolve due to their specifics, but the approach may be applicable to general purpose programming languages as well. The approach was tested on a real-world domain-specific language that is used in a financial domain. We proposed three improvements and current users helped us evaluate them. We found that the proposed improvements would reduce code cloning, which provides evidence that the approach can be used in a real-world environment. Furthermore, this work provides a solid basis for further research in the area of application of code cloning detection results. In particular, code cloning detection results and the ideas we presented show potential to be extended and used to facilitate domain analysis.

This thesis describes and evaluates how extending Intel's Concurrent Collections (CnC) programming model can address the problem of hybrid programming with high performance and low energy consumption, while retaining the ease of use of data-flow programming. The CnC model is a declarative, dynamic light-weight task based parallel programming model and is implicitly deterministic by enforcing the single assignment rule, properties which ensure that problems are modelled in an intuitive way. CnC offers a separation of concerns by allowing algorithms to be expressed as a two stage process: first by decomposing a problem into components and specifying how components interact with each other, and second by providing an implementation for each component. By facilitating the separation between a domain expert, who can provide an accurate problem specification at a high level, and a tuning expert, who can tune the individual components for better performance, we ensure that tuning and future development, such as replacement of a subcomponent with a more efficient algorithm, become straightforward. A recent trend in mainstream desktop systems is the use of graphics processor units (GPUs) to obtain order-of-magnitude performance improvements relative to general-purpose CPUs. In addition, the use of FPGAs has seen a significant increase for applications that can take advantage of such dedicated hardware. We see that computing is evolving from using many core CPUs to ``co-processing" on the CPU, GPU and FPGA, however hybrid programming models that support the interaction between multiple heterogeneous components are not widely accessible to mainstream programmers and domain experts who have a real need for such resources. We propose a C-based implementation of the CnC model for enabling parallelism across heterogeneous processor components in a flexible way, with high resource utilization and high programmability. We use the task-parallel HabaneroC language (HC) as the platform for implementing CnC-HabaneroC (CnC-HC), a language also used to implement the computation steps in CnC-HC, for interaction with GPU or FPGA steps and which offers the desired flexibility and extensibility of interacting with any other C based language. First, we extend the CnC model with tag functions and ranges to enable automatic code generation of high level operations for inter-task communication. This improves programmability and also makes the code more analysable, opening the door for future optimizations. Secondly, we introduce a way to specify steps that are data parallel and thus are fit to execute on the GPU, and the notion of task affinity, a tuning annotation in the specification language. Affinity is used by the runtime during scheduling and can be fine-tuned based on application needs to achieve better (faster, lower power, etc.) results. Thirdly, we introduce and develop a novel, data-driven runtime for the CnC model, using HabaneroC (HC) as a base language. In addition, we also create an implementation of the previous runtime approach and conduct a study to compare the performance. Next, we expand the HabaneroC dynamic work-stealing runtime to allow cross-device stealing based on task affinity. Cross-device dynamic work-stealing is used to achieve load balancing across heterogeneous platforms for improved performance. Finally, we implement and use a series of benchmarks for testing the model in different scenarios and show that our proposed approach can yield significant performance benefits and low power usage when using a hybrid execution.

Flecs is a framework for facilitating rapid implementation of communication protocols. Forwarding functionality of protocols can be modeled as a combination of packet processing components called abstract switching elements or Ases. The design of Ases is constrained by the axioms of communication which enables us to formally analyze forwarding mechanisms in communication networks. Ases can be connected in a directed graph to define complex forwarding functionality. We have developed Flecs on top of the Click modular router. The compilers in the Flecs framework translate protocol specifications into its Click implementation. We claim that the use of our framework reduces the implementation time by allowing the programmer to specify Ases and the forwarding configuration in a high-level meta-language and produces reasonably efficient implementations. It allows rapid prototyping through configuration, as well as specialized implementation of performance-critical functionality through inheritance.

Flecs is a framework for facilitating rapid implementation of communication protocols. Forwarding functionality of protocols can be modeled as a combination of packet processing components called abstract switching elements or Ases. The design of Ases is constrained by the axioms of communication which enables us to formally analyze forwarding mechanisms in communication networks. Ases can be connected in a directed graph to define complex forwarding functionality. We have developed Flecs on top of the Click modular router. The compilers in the Flecs framework translate protocol specifications into its Click implementation. We claim that the use of our framework reduces the implementation time by allowing the programmer to specify Ases and the forwarding configuration in a high-level meta-language and produces reasonably efficient implementations. It allows rapid prototyping through configuration, as well as specialized implementation of performance-critical functionality through inheritance.

Thesis (D. Ed.)--Ball State University, 2009. / Title from PDF t.p. (viewed on Nov. 12, 2009). Includes bibliographical references (p. 148-159).

A Domain-Specific Modeling Approach This study has presented a component-based domain modeling approach that provides an environment for simplifying and accelerating software development and analysis, and improves software reusability, maintainability, and productivity. With highlevel design abstraction, constraints of application domains, and the guidance of domain rules, the proposed component-based framework offers an effective solution to modeling and automating the development and deployment of software application. Meta-modeling will be used in this study to define the domain notations, rules, and constraints for component composition within a specific domain context. A domain-specific graphical design environment will also be proposed to simplify and accelerate the software development by simply dragging and dropping pre-built components with minimal programming effort. The modeling of components can be further extended with the specification of their dependability and real-time constraints. / Related work -- Component composition -- Domain-specific modeling -- Model-based component composition environment for a specific domain -- Mobile service creation framework (MCSF) -- A model-driven approach to implementing dependable component-based mobile services -- A model-driven approach to implementing component-based real-time mobile services / Related work -- Component composition -- Domain-specific modeling -- Model-based component composition environment for a specific domain -- Mobile service creation framework (MCSF) -- A model-driven approach to implementing dependable component-based mobile services -- A model-driven approach to implementing component-based real-time mobile services. / Department of Computer Science

Domain-specific languages can significantly speed up the development of software applications. However, it usually takes a few iterations of the language design before it achieves such power. At the same time, many domains tend to evolve quite often today, which implies that domain-specific languages have to evolve accordingly. Thus, being able to evolve a language in a painless manner is crucial. Unfortunately, current state-of-the-art research does not provide enough answers on how to efficiently evolve domain-specific languages. We present an approach to evolving a language in order to reduce the amount of code cloning it introduces. The approach specifically targets those languages whose design causes users to create many duplicated code segments. We target domain-specific languages as they tend to be more challenging to evolve due to their specifics, but the approach may be applicable to general purpose programming languages as well. The approach was tested on a real-world domain-specific language that is used in a financial domain. We proposed three improvements and current users helped us evaluate them. We found that the proposed improvements would reduce code cloning, which provides evidence that the approach can be used in a real-world environment. Furthermore, this work provides a solid basis for further research in the area of application of code cloning detection results. In particular, code cloning detection results and the ideas we presented show potential to be extended and used to facilitate domain analysis.

This dissertation is dedicated to the problem of device driver reliability. Software defects in device drivers constitute the biggest source of failure in operating systems, causing significant damage through downtime and data loss. Previous research on driver reliability has concentrated on detecting and mitigating defects in existing drivers using static analysis or runtime isolation. In contrast, this dissertation presents an approach to reducing the number of defects through an improved device driver architecture and development process. In analysing factors that contribute to driver complexity and induce errors, I show that a large proportion of errors are due to two key shortcomings in the device-driver architecture enforced by current operating systems: poorly-defined communication protocols between drivers and the operating system, which confuse developers and lead to protocol violations, and a multithreaded model of computation, which leads to numerous race conditions and deadlocks. To address the first shortcoming, I propose to describe driver protocols using a formal, state-machine based, language, which avoids confusion and ambiguity and helps driver writers implement correct behaviour. The second issue is addressed by abandoning multithreading in drivers in favour of a more disciplined event-driven model of computation, which eliminates most concurrency-related faults. These improvements reduce the number of defects without radically changing the way drivers are developed. In order to further reduce the impact of human error on driver reliability, I propose to automate the driver development process by synthesising the implementation of a driver from the combination of three formal specifications: a device-class specification that describes common properties of a class of similar devices, a device specification that describes a concrete representative of the class, and an operating system interface specification that describes the communication protocol between the driver and the operating system. This approach allows those with the most appropriate skills and knowledge to develop specifications: device specifications are developed by device manufacturers, operating system specifications by the operating system designers. The device-class specification is the only one that requires understanding of both hardware and software-related issues. However writing such a specification is a one-off task that only needs to be completed once for a class of devices. This approach also facilitates the reuse of specifications: a single operating-system specification can be combined with many device specifications to synthesise drivers for multiple devices. Likewise, since device specifications are independent of any operating system, drivers for different systems can be synthesised from a single device specification. As a result, the likelihood of errors due to incorrect specifications is reduced because these specifications are shared by many drivers. I demonstrate that the proposed techniques can be incorporated into existing operating systems without sacrificing performance or functionality by presenting their implementation in Linux. This implementation allows drivers developed using these techniques to coexist with conventional Linux drivers, providing a gradual migration path to more reliable drivers.

Thesis (Ph. D.)--University of Alabama at Birmingham, 2007. / Additional advisors: Barrett R. Bryant, Marjan Mernik, Mikhail Auguston, Chengcui Zhang, Brian Toone. Description based on contents viewed Feb. 8, 2008; title from title screen. Includes bibliographical references (p. 143-151).