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A generalized Womersley model of a nonstationary axisymmetric flow of a viscous incompressible fluid through a tube of circular cross-section to periodic pressure fluctuations at the inlet of the tube is obtained due for the case of a fluid with complicated rheology. The rheological parameters of the fluid are viscosity and four relaxation coefficients for strains and stresses of the first and second order. Such rheology is proper to the non-Newtonian viscoelastic fluids with mesostructure, namely technical and biological micro/ nanofluids. It was shown that with the increase of the relaxation coefficients of the first/second order the flow rate, the average and maximum velocities decrease/increase, accordingly. Simultaneous changes in these parameters can lead to complex changes in the velocity profile, especially for higher harmonics. The studied regularities can explain the deviations of the flow parameters of different micro/nanofluids from the values predicted by the classical Womersley solution for a homogeneous Newtonian fluid, which does not take into account viscous dissipation during the rearrangement of the fluid mesostructure.

A new approach is shown that mechanically proves various theorems in plane geometry by recasting them in terms of constraint satisfaction. A Python 3 implementation called GEOPAR affords transparent proofs of well-known theorems as well as new ones, including a generalization of Morley’s Theorem.

Test-yourself questions are effective examples of formative assessment, and have been shown to promote learners' active interaction with materials and knowledge mastery through frequent practice. However, the cost of developing and implementing engaging test-yourself activities can be problematic in large-scale web-based learning environments; a lack of built-in scaffolding to guide learners is also a challenge. We introduce Guided-KNOWLA, an improvement of KNOWLA -- a learning tool has learners assemble a given set of mixed-size scrambled fragments into a logical order using a web-based interface, accompanied by motivational step-by-step hint/guidance as enhancements. We conducted an exploratory study with graduate learners to examine their attitudes toward Guided-KNOWLA activities, measured by perceived usefulness and comparative formats for formative assessment. Preliminary results suggest that using the Guided-KNOWLA were useful in helping learners master online materials and were a preferred format of "test-yourself" practice to multiple-choice questions.

UML creates useful visualizations but they become monolithic, complex, and expensive to maintain. In agile development, documentation is secondary, which discourages the use of UML even further. We introduce an in-code, just-in-time, maintainable approach to UML, supported by a tool called PREXEL. PREXEL minimizes interruptions in coding by allowing concise in-line specifications which automatically synthesize in-code graphical ASCII class models, class and method skeletons, and class relationships.

The assessment of learning in large online courses requires tools that are valid, reliable, easy to administer, and can be automatically scored. We have evaluated an online assessment and learning tool called Knowledge Assembly, or Knowla. Knowla measures a student’s knowledge in a particular subject by having the student assemble a set of arbitrarily sized scrambled fragments into a logical order using a web-based interface. Instructors can use Knowla to create assessments and grading criteria. Initial testing of the tool indicates that the measure is reliable and that students access critical thinking skills as they engage with the material. Additionally, testing demonstrates that Knowla can be used to assess learning gains in a subject area. Knowla also shows promise as a learning tool and has already been integrated into university courses.

This paper explores and describes die different facets of facilitating an online security course. It describes the purpose of a facilitator, the qualifications necessary for a facilitator, defines the role of the facilitator, and finally describes the activities of a facilitator.

The assessment of learning in large online courses such as Massive Online Open Courses, or MOOCs, requires tools that are valid, reliable, and can be automatically administered and scored. We have developed and assessed a tool called Knowledge Assembly for Learning and Assessment, or KNOWLA. The tool measures a student's knowledge in a particular subject by having her assemble a set of scrambled phrases into a logical order. Initial testing indicates that KNOWLA is reliable, and can be used to measure learning gains. KNOWLA also shows promise as a learning tool.

The emergence and popularity of Cloud computing could not have happened were it not for the massive amount of underlying software reuse, as reuse of services and applications is what saves development dollars and allows IT infrastructure to adapt more nimbly to the changing environment. Software fosters two reuse syntaxes: Sharing and reuse of human-readable source code (open source), or sharing and reuse of machine-readable binary code (proprietary). Software also caters to two reuse semantics: where the software is either prepackaged as components or as frameworks. In this chapter, the authors examine software reuse in the Cloud. By categorizing it in these dual categories, they glimpse the practices that prime Cloud-based software for massive reuse.

Code reuse has long been a holy grail of Information Technology. When realized, it is manifested either by sharing source code or by sharing binary code. The free software and open source movements promote the sharing of source code. The proprietary world promotes market mechanisms through exclusive rights of ownership to binary code, protected by licenses and copy protection mechanisms. When binary code is shared by many owners in the proprietary world, it is packaged as either software libraries or software frameworks, abstractions in which common binary code providing generic functionality can be leveraged, extended, and specialized. With software libraries, owners write code that calls library code; with software frameworks, owners write callback code that is called by framework code. This paper details benefits and drawbacks of these two types of shared binary code abstractions and suggests best practices, from a practical perspective and concerning large and complex implementations of software frameworks in sizable enterprises.

The paper applies recent advances in object-oriented research to propose a class-level framework for discrete event simulations. The advances are in object-oriented analysis and design, the Unified Modeling Language, and the identification of application class frameworks as a discipline in and of itself.

In the first part of this paper it is proved that a property of topologicalspaces recently formulated by Lorch and Tong is equivalent to G δ diagonality, thereby yielding an alternate proof of a recent result of theirs. This equivalence also yields several related theorems. In the second part it is shown that analogous results are valid for spaces with G -Souslin diagonals. Consideration of these analogs yields the corollary that compact Hausdorff spaces which are countable unions of metrizable G -Souslin subspaces are metrizable.

It is shown that perfect open multivalued maps preserve Z \mathcal {Z} -analytic sets (which include compact zero sets) as well as other objects of descriptive set theory. The concept of “distinguishability", introduced by Frolík, is applied to multivalued maps, yielding a new class of such maps with similar preservation properties. That the projection of a compact zero set is a zero set is one corollary, and another is a generalized G δ {\mathcal {G}_\delta } diagonal metrization theorem.