Open Unification for Program Query Languages

We present a new technique for helping developers understand heap referencing properties of object-oriented programs and how the actions of the program affect these properties. Our dynamic analysis uses the aliasing properties of objects to synthesize a set of roles; each role represents an abstract object state intended to be of interest to the developer. We allow the developer to customize the analysis to explore the object states and behavior of the program at multiple different and potentially complementary levels of abstraction. The analysis uses roles as the basis for three abstractions: role transition diagrams, which present the observed transitions between roles and the methods responsible for the transitions; role relationship diagrams, which present the observed referencing relationships between objects playing different roles; and enhanced method interfaces, which present the observed roles of method parameters. Together, these abstractions provide useful information about important object and data structure properties and how the actions of the program affect these properties. We have implemented the role analysis and have used this implementation to explore the behavior of several Java programs. Our experience indicates that, when combined with a powerful graphical user interface, roles are a useful abstraction for helping developers explore and understand the behavior of object-oriented programs.

For a very long time truth-value gaps were under a cloud of suspicion because they were considered logically unmanageable. So Frege declared that:“as regards concepts we have a requirement of sharp delimitation; if this were not satisfied it would be impossible to set forth logical laws about them”.Three-valued logic promised to dispel the cloud but in the eyes of many it had promised more than it could deliver. So in response to Reichenbach's plea for a three-valued quantum logic Russell replied:“This is one of a number of questions as to which I am prevented from accepting a certain view by difficulties in carrying it out, but am prepared to alter my opinion if technical skill supplies an answer to my difficulties”.‘By now technical skill has supplied many alternative systems of three-valued logic, but few answers and numerous additional difficulties.’

In this chapter, we introduce an instance of dynamic logic, called JavaDL, that allows us to reason about Java programs. Dynamic logic extends first-order logic and makes it possible to consider several program states in a single formula. Its principle is the formulation of assertions about program behavior by integrating programs and formulas within a single language. We present a sequent calculus for JavaDL, which is used in the KeY System for verifying Java programs. Deduction in this calculus is based on symbolic program execution and simple program transformations and is, thus, close to a programmer's understanding of Java. Besides rules for symbolic execution, the calculus contains rules for program abstraction and modularization, including invariant rules for reasoning about loops and rules that replace a method invocation by the method's contract.

The goal of the JAVAVIS system is to help students understand what is happening in a Java program during execution. The primary focus of the first release is on sequential Java programs, although there is some support for visualizing concurrent threads. The system uses the Java Debug Interface (JDI), so there are no modifications needed in the Java source code for the extraction of information. The system shows the dynamic behavior of a running program by displaying several object diagrams and a single sequence diagram. There is one object diagram for each active method on the call stack. All modifications in the diagrams are done by smooth transitions.

Inheritance is a crucial part of object-oriented programming, but its use in practice, and the resulting large-scale inheritance structures in programs, remain poorly understood. Previous studies of inheritance have been relatively small and have generally not considered issues such as Java's distinction between classes and interfaces, nor have they considered the use of external libraries. In this paper we present the first substantial empirical study of the large-scale use of inheritance in a contemporary OO programming language. We present a suite of structured metrics for quantifying inheritance in Java programs. We present the results of performing a corpus analysis using those metrics to over 90 applications consisting of over 100,000 separate classes and interfaces. Our analysis finds higher use of inheritance than anticipated, variation in the use of inheritance between interfaces and classes, and differences between inheritance within application types compared with inheritance from external libraries.

Koide’s prediction of the tau mass may be formulated as a condition on the three eigenvalues of a quantum Fourier series, using simple parameters, and similar triplets have been found for neutrino and hadron masses [2]. Assuming these parameters arise from quantum gravity, one would like to understand them from the more abstract context of category theory. In particular, whereas the logic of lepton spin is a linear analogue of the ordinary Boolean logic of the category of sets, mass triplets suggest an analogous ternary logic, requiring higher dimensional categorical structures.

How to identify class comment types? A multi-language approach for class comment classification

Contemporary China’s urban development has been driven by a logic of homogenization, quantification, and exchange value—hallmarks of the globally admired ‘Chinese speed.’ Yet this rapid abstraction of urban space has increasingly disconnected from the lived experiences of residents, fostering widespread disillusionment and eroding the public’s confidence in everyday spatial participation. As a result, the city risks losing its capacity for organic renewal. In stark contrast, a group of working poets—migrant labourers engaged in creative self-expression—inhabits the same spaces while producing alternative, poetic forms of everyday life. This article employs Henri Lefebvre’s spatial dialectics to analyse the divergent spatial practices of urban residents and working poets, revealing the roots of their contrasting experiences. Through interdisciplinary inquiry—combining urban theory, field interviews, and audiovisual experimentation—this research culminates in the creation of an essay film that constructs a representational image-space based on the working poets’ practices. By doing so, it proposes a narrative intervention that not only critiques dominant spatial discourses but also invites publics to reclaim everyday space through creative, poetic acts. Ultimately, the article positions artmaking as a method of urban problem-solving—foregrounding difference, imagination, and self-identification as vital tools for reactivating the right to the city.

Correctly predicting the direction that branches will take is increasingly important in today's wide-issue computer architectures. The name program-based branch prediction is given to static branch prediction techniques that base their prediction on a program's structure. In this paper, we investigate a new approach to program-based branch prediction that uses a body of existing programs to predict the branch behavior in a new program. We call this approach to program-based branch prediction, evidence-based static prediction, or ESP. The main idea of ESP is that the behavior of a corpus of programs can be used to infer the behavior of new programs. In this paper, we use a neural network to map static features associated with each branch to the probability that the branch will be taken. ESP shows significant advantages over other prediction mechanisms. Specifically, it is a program-based technique, it is effective across a range of programming languages and programming styles, and it does not rely on the use of expert-defined heuristics. In this paper, we describe the application of ESP to the problem of branch prediction and compare our results to existing program-based branch predictors. We also investigate the applicability of ESP across computer architectures, programming languages, compilers, and run-time systems. Averaging over a body of 43 C and Fortran programs, ESP branch prediction results in a miss rate of 20%, as compared with the 25% miss rate obtained using the best existing program-based heuristics.

An active set is a unifying space being able to act as a “bridge” for transferring information, ideas and results between distinct types of uncertainties and different types of applications. An active set is a set of agents who independently deliver true or false values for a given proposition. It is not a simple vector of logic values for different propositions, the results are a vector but the set is not. The difference between an ordinary set and active set is that the ordinary set has passive elements with values of the attributes defined by an external agent, in the active set any element is an agent that internally defines the value of a given attribute for a passive element. So agents in many cases are in a logic conflict and this generates semantic uncertainty on the evaluation. Criteria and agents are the two variables by which we give different logic values to the same attribute or proposition. In modal logic, given a proposition, we can evaluate the proposition only when we know the worlds where the proposition is located. In epistemic logic any world is an agent that knows that the proposition is true or false. The active set is a set of agents as in epistemic logic but the difference with modal logic is that all the agents (worlds) are not separate but are joined in the evaluation of the given proposition. In active set for one agent and one criteria we have one logic value but for many agents and criteria the evaluation is not true or false but is a matrix of true and false. This matrix is not only a logic evaluation as in the modal logic but give us the conflicting structure of the active set evaluation. The agent multi dimensional space to evaluate active set also includes the Hilbert multidimensional space where is possible to simulate quantum logic gate. New logic operation are possible as fuzzy gate operations and more complex operations as conflicting solving, consensus operations, syntactic inconsistency, semantic inconsistency and knowledge integration. In the space of the agents evaluations morphotronic geometric operations are a new frontier to model new types of computers. In this paper we show the connection between classical, fuzzy, evidence theory and active sets.

Open Distance Learning (ODL) is an approach in education practices in Open University Malaysia (OUM). One of its programs that are offered through ODL is the Bachelor of Psychology (BPSY) and it is one of the programs with the highest student intake in OUM. Since the program has been commencing for more than 10 years, it is the time to evaluate whether the program needs any revisions or improvements. Thus, the aim of the study is to determine the level of satisfaction of students on the Psychology program offered in OUM. A questionnaire was developed for this purpose which includes 4 areas of students' satisfaction, namely the learning materials, student perceptions on their tutors, assessment matters, as well as the overall program structure. The questionnaires were distributed to more than 1000 active students through online and face-to-face tutorials. A total of 439 students participated in the study. The results indicated that students are most satisfied with the overall program structure and least satisfied with the assessment matters with the mean score of 3.98 and 3.59 respectively. The study certainly benefits the university in taking action to revise and improve the program. Recommendation for future research is included at the end of the paper.

The possibility of basing quantum computations on the laws of genuine quantum (non-Boolean) logic is shown. We investigate the new options provided by this approach and consider its relevance to the existing computational problems. A simple example of quantum adding machine that works according to this idea is studied. This example shows that the proposed new way of making quantum computations in the natural way utilizes `probabilistic' (or `fuzzy') features of quantum objects and allows to deal with non- exact data.

In this study, the crosstalk effects are minimized in coupled multi-line wires based on repeater staggering in ternary logic. For more accuracy, the impact of the coupling capacitance is also considered in our calculations. Our results indicate that the number of repeaters required for optimizing the delay of the multilayer graphene nanoribbon (MLGNR) interconnect is, on average, 43% lower than multi-walled carbon nanotube (MWCNT) interconnect. Moreover, the optimized delay of the MLGNR interconnect is, on average, 48% lower than MWCNT interconnect. The ternary repeater insertion reduces the delay of the MWCNT and MLGNR interconnects carrying ternary signals by 61% and 51%, respectively. The staggered repeater insertion is applied as a practical approach for eliminating the crosstalk noise in the transmitted ternary signals in a multi-line coupled structure. Our results demonstrate that the delay and energy of the staggered repeater-inserted MLGNR interconnects are, on average, 42% and 37% lower than their MWCNT counterparts. Furthermore, the impacts of the process variations are investigated using comprehensive Monte Carlo simulations and the optimized ternary multi-line MLGNR interconnect functions correctly and considerably robustly compared to their MWCNT counterpart.

The rapid growth of stored data, particularly on magnetic disks, is doubling annually for each department within a company, creating a pressing need for efficient database management. While database design is a fundamental step in establishing a high-performance system, it alone is insufficient to ensure optimal efficiency. Query optimization plays a critical role in improving data transaction speed, reducing query execution time, and enhancing overall system responsiveness. This study evaluates various relational database models under different data volumes to analyze their impact on query performance. Using the Cost-Based Optimizer method and access time measurements, we assess query costs and determine the factors influencing performance. The results indicate that among the three database models analyzed, ERD-3 consistently delivers superior performance, especially in handling complex queries. This is attributed to its modular structure, strategic indexing, and reduced full table scans, which collectively minimize query execution costs. Additionally, several key factors significantly affect query performance, including record count, attribute size, query complexity, primary and unique key usage, indexing strategies, order-by clauses, index sequences, and SQL function application. This research contributes to the field of database optimization by demonstrating that ERD structuring and cost-based query analysis significantly improve system efficiency in large-scale environments. These findings emphasize the necessity of a well-structured, scalable database model and efficient query processing techniques to accommodate large-scale data growth. The study’s conclusions provide a foundation for advanced optimization strategies, ensuring that modern database systems remain efficient and adaptable to evolving data demands.

When software developers want to understand the reason for a program's behavior, they must translate their questions about the behavior into a series of questions about code, speculating about the causes in the process. The Whyline is a new kind of debugging tool that avoids such speculation by instead enabling developers to select a question about program output from a set of “why did and why didn't” questions extracted from the program's code and execution. The tool then finds one or more possible explanations for the output in question. These explanations are derived using a static and dynamic slicing, precise call graphs, reachability analyses, and new algorithms for determining potential sources of values. Evaluations of the tool on two debugging tasks showed that developers with the Whyline were three times more successful and twice as fast at debugging, compared to developers with traditional breakpoint debuggers. The tool has the potential to simplify debugging and program understanding in many software development contexts.