Deadlock detection is very difficult in a distributed database system because no controller has complete and current information about the system and data dependencies. The deadlock problem is intrinsic to a distributed database system which employs locking as its concurrency control algorithm. This paper attempts a comprehensive study of deadlock detection in distributed database systems. Afterwards, a deadlock detection algorithm is presented. The algorithm is based on creating Linear Transaction Structure (LTS), Distributed Transaction Structure (DTS), finding local and global cycle, deciding priority Id of the transaction and localglobal abortion. The proposed algorithm does not detect any false deadlock or exclude any really existing deadlocks. In this technique global deadlock is not dependent on the local deadlock.

Self-regulated learning has become an important construct in education research in the last few years. Selfregulated learning in its simple form is the learner’s ability to monitor and control the learning process. There is increasing research in the literature on how to support students become more self-regulated learners. However, the advancement in the information technology has led to paradigm changes in the design and development of educational content. The concept of learning object instructional technology has emerged as a result of this shift in educational technology paradigms. This paper presents the results of a study that investigated the potential educational effectiveness of a pedagogical framework based on the self-regulated learning theories to support the design of learning object systems to help computer science students. A prototype learning object system was developed based on the contemporary research on self-regulated learning. The system was educationally evaluated in a quasi-experimental study over two semesters in a core programming languages concepts course. The evaluation revealed that a learning object system that takes into consideration contemporary research on self-regulated learning can be an effective learning environment to support computer science education.

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The most current computing curriculum guidelines focus on designing learning materials to prepare students for lifelong learning. Under the lifelong learning paradigm, students are responsible for controlling and monitoring their learning processes. This undoubtedly includes the ability to choose suitable learning materials. Correspondingly, instructional paradigms are shifting from teacher-centered to more student-centered models that require students to be self-regulated learners. On the other hand, recent trends in learning materials’ instructional design focus on moving toward the concept of Learning Object-based instructional technology. A learning object is a unit of instruction with a specific pedagogical objective that can be used and reused in different learning contexts. Designing learning objects to support students in their self-regulated learning is not an easy task due to the lack of underlying pedagogical frameworks. It is difficult to find learning objects related to students’ specific preferences and requirements. In this study, a number of learning objects are designed to support the self-regulated learning of programming languages concepts based on the theory of learning styles. Students’ interactions with these learning objects are managed using an online learning object repository. The repository helps students identify their preferred learning styles and find the relevant learning objects. The results of the evaluations of these learning objects revealed that students perceive them to be easy to use and effective in supporting their learning about different programming languages concepts

An important aim in the design of the Timor programming language is to provide programmers with features which enable them to build complex systems from components which can be developed in isolation from each other (i.e. without knowledge of each other's existence). The database transaction concept serves as an interesting test case for this objective, since it is a general concept which can be applied to many different applications. The paper discusses those features of Timor which allow this objective to be achieved.