Taking I/O seriously: resolution reconsidered for disk

Journal ArticleModern compilation techniques can give Prolog programs, in the best cases, a speed comparable to C. However, Prolog has proven to be unacceptable for data-oriented queries for two major reasons: its poor termination and complexity properties for Datalog, and its tuple-at-a-time strategy. A number of tabling frameworks and systems have addressed the first problem, including the XSB system which has achieved Prolog speeds for tabled programs. Yet tabling systems such as XSB continue to use the tuple-at-a-time paradigm. As a result, these systems are not amenable to a tight interconnection with disk-resident data. However, in a tabling framework the difference between tuple-at-a-time behavior and set-at-a-time can be viewed as one of scheduling. Accordingly, we define a breadth-first set-at-a-time tabling strategy and prove it iteration equivalent to a form of semi-naive magic evaluation. That is, we extend the well-known asymptotic results of Seki [10] by proving that each iteration of the tabling strategy produces the same information as semi-naive magic. Further, this set-at-a-time scheduling is amenable to implementation in an engine that uses Prolog compilation. We describe both the engine and its performance, which is comparable with the tuple-at-a-time strategy even for in-memory Datalog queries. Because of its performance and its fine level of integration of Prolog with a database-style search, the set-at-a-time engine appears as an important key to linking logic programming and deductive databases

Three Denerations of DBMS

This paper describes the evolution of data base technology from early computing to the sophisticated systems of today. It presents an overview of the most popular data base management systems architectures such as hierarchical, network, relational and object-oriented. The last section of this paper presents a view of the factors that will influence the future of data base technology

Data, Analytics and Community-Based Organizations: Transforming Data to Decisions for Community Development

Big data and analytics for community-focused nonprofits can improve analytic capabilities and increase impact. However, Community-based organization needs do not match well with conventional notions of data and analytics. Decentralized model for data-driven research may be preferred, but centralized model is dominant. CBOs can articulate data needs, but are often not yet able to access relevant data easily and use data effectively. Finally, certain values maximize impact of big data and analytic

Automated Evaluation for Distributed System Assignments

A distributed system can exist in numerous states, including many erroneous permutations that could have been addressed in the code. As distributed systems such as cloud computing and microservices gain popularity, involving distributed com- puting assignments is becoming increasingly crucial in Computer Science and related fields. However, designing such systems poses various challenges, such as considering parallel executions, error-inducing edge cases, and interactions with external systems. Typically, distributed assignments require students to implement a system and run multiple instances of the same code to behave as distributed. However, such assign- ments do not encourage students to consider the potential edge cases that external systems may induce when interacting with their code. Assignments that execute a combination of student submissions as a single system promote high-quality design discussions before and during code writing and encourage students to consider how to handle faults generated by other systems. Testing such assignments is labor-intensive and involves repetitive tasks of setting up and destroying a virtual environment in which to test the system. In some cases, inducing a specific type of fault may require modifying the submitted source code, which is strongly discouraged. This research project explores the necessity, design, and implementation of Distributed CodEval, a tool that enables course instructors to define test cases for automating the evaluation of distributed system assignments

Family-Owned or -Managed Higher Education Institutions: A Special Kind of Governance

Thesis advisor: Hans de WitThe family ownership context has been investigated across many business settings, within the manufacturing, trade, and services industries. The consensus among scholars has been that families that own and operate firms act in self-serving ways and frame organizational problems and make decisions with the primary goal of satisfying the family’s affective needs, i.e., preserve or augment what is referred to as socioemotional wealth. However, the theoretical reasoning of socioemotional wealth theory may fall apart in traditional university settings, where self-serving behaviors may lead to (pronounced) agency conflict. Universities have been long understood for their politicized governance environs in which multiple stakeholder groups have representation in decision-making. Within this reality, families involved in higher education management may be challenged to act self-servingly and protect or enhance certain socioemotional wealth. They may need to act in altruistic ways to avoid agency conflict. I investigate whether this is the case through a single, critical case study approach conducted at one family-owned or -managed university in India. I rely on what Yin (2003) refers to as “rival explanation as patterns” to test socioemotional theory relative to a rival theoretical framework. I ask the important question of whether this rival theory can address the limitations of socioemotional wealth theory when applied to the higher education context. As expected, findings generally suggest that where socioemotional wealth theory fails to capture family decision-making behaviors, the rival theory is relevant. This finding is important to consider and has several implications to theory, practice, and future research. Importantly, the findings support that current family-owned business theorizing is not enough to capture family decision-making behaviors in the context of traditional university settings.Thesis (PhD) — Boston College, 2020.Submitted to: Boston College. Lynch School of Education.Discipline: Educational Leadership and Higher Education

Compilation of bottom-up evaluation for a pure logic programming language

Abstraction in programming languages is usually achieved at the price of run time efficiency. This thesis presents a compilation scheme for the Starlog logic programming language. In spite of being very abstract, Starlog can be compiled to an efficient executable form. Starlog implements stratified negation and includes logically pure facilities for input and output, aggregation and destructive assignment. The main new work described in this thesis is (1) a bottom-up evaluation technique which is optimised for Starlog programs, (2) a static indexing structure that allows significant compile time optimisation, (3) an intermediate language to represent bottom-up logic programs and (4) an evaluation of automatic data structure selection techniques. It is shown empirically that the performance of compiled Starlog programs can be competitive with that of equivalent hand-coded programs

Cogitator : a parallel, fuzzy, database-driven expert system

The quest to build anthropomorphic machines has led researchers to focus on knowledge and the manipulation thereof. Recently, the expert system was proposed as a solution, working well in small, well understood domains. However these initial attempts highlighted the tedious process associated with building systems to display intelligence, the most notable being the Knowledge Acquisition Bottleneck. Attempts to circumvent this problem have led researchers to propose the use of machine learning databases as a source of knowledge. Attempts to utilise databases as sources of knowledge has led to the development Database-Driven Expert Systems. Furthermore, it has been ascertained that a requisite for intelligent systems is powerful computation. In response to these problems and proposals, a new type of database-driven expert system, Cogitator is proposed. It is shown to circumvent the Knowledge Acquisition Bottleneck and posess many other advantages over both traditional expert systems and connectionist systems, whilst having non-serious disadvantages.KMBT_22

Gender In Motion: Negotiating Bengali Social Statuses Across Time and Territories

Hindu Indian Bengalis as an ethno-linguistic and transnational group have negotiated their social locations historically, contemporaneously, and transnationally. In this dissertation, I examine and argue how transnational migration is the most recent in a long line of Bengali strategies to negotiate their social location vis-à-vis other populations in India. Since the early years of the nineteenth century, in Bengal specifically, a series of socio-political dynamics have reshaped and reconstituted Bengali social status. These dynamics can be observed across various geographic scales - national, regional, and local -- and have continued to inform their contemporary gender relations. En route to this examination, the dissertation exposes assumptions about who constitutes families, problematizes family centrally en route to examining spousal relations among Indian-Bengalis. I have examined the lived realities and experiences of migrant spouses in the U.S. and their family living in India amidst differing—and often conflicting-- imaginaries and practices of families. Through my work, I thus illustrate that family and marriage relations can be, and often are, strategic and fluid even as many people view them as structural and enduring. Over time, representations of the idealized Bengali family, of manhood and of womanhood have all shifted, reflecting sociopolitical and economic changes. A constant, however, has been the central role of gender in all these imaginaries and realized configurations. In this dissertation, I employ a gendered optic, a heightened sensibility to what they communicate about gender. As I examine in my work, gendered boundaries amid the Bengali population can be found in a deeply rooted history, a colonial legacy, and one, although repackaged, that continues to be seen contemporaneously. Bengalis\u27 transnational negotiations in family and marriage expand our understanding of transnational gender relations across broad social and historical scales, particularly the transnational. In this vein, the dissertation contributes significantly to the field of gender studies, specifically the field of feminist theorizing and intersectionality studies, postcolonial and South Asian studies, and to the scholarship on migration and transnational migration studies