A new flow model for highly separated airfoil flows at low speeds

An analytical model for separated airfoil flows is presented which is based on experimentally observed physical phenomena. These include a free stagnation point aft of the airfoil and a standing vortex in the separated region. A computer program is described which iteratively matches the outer potential flow, the airfoil turbulent boundary layer, the separated jet entrainment, mass conservation in the separated bubble, and the rear stagnation pressure. Separation location and pressure are not specified a priori. Results are presented for surface pressure coefficient and compared with experiment for three angles of attack for a GA(W)-1, 17% thick airfoil

An analytical model for highly seperated flow on airfoils at low speeds

A computer program was developed to solve the low speed flow around airfoils with highly separated flow. A new flow model included all of the major physical features in the separated region. Flow visualization tests also were made which gave substantiation to the validity of the model. The computation involves the matching of the potential flow, boundary layer and flows in the separated regions. Head's entrainment theory was used for boundary layer calculations and Korst's jet mixing analysis was used in the separated regions. A free stagnation point aft of the airfoil and a standing vortex in the separated region were modelled and computed

JSP Custom Tag for Pagination, Sorting and Filtering – A Case Study

Tag libraries have the power of reducing complex functionalities to one liners by separating out implementation part from tag declarations. Tags do hide the implementation specific tasks from the end user by making the code more readable. The frequently and widely used functionality in any application is database operations which involve lot of code repetition. Such a repeated code can be hidden behind a couple of custom tags where the end user can be concerned only with the tag usage which renders the application bug free and also aids in rapid application development. Majority of automation softwares at the minimal incorporate functionalities for interaction with repository of data . The need for quick searching of required data and retrieving subsets of data demand sorting, pagination, and filtering capabilities to be an integral part of any application. With the exponential growth in data these functionalities become mandatory to be incorporated in any application irrespective of its type and size. Further, Rich Internet Application (RIA) demands an attractive graphical user interface providing visual clues on the type of data to be entered or to be displayed. In order to cater a solution to this issue, in the current paper, the authors have designed and implemented a JSP custom tag for displaying a database table data in columns of different types such as check boxes, images, hyperlinks etc. Boolean attributes are added to the tag for enabling one or more of the features corresponding to pagination, sorting and filtering

Custom Annotation for Execution of Data Manipulation Commands in a Generic Manner ? A Case Study

Java annotations are the tags employed for providing meta data for Java code. They can be attached to a class, method, or a field to provide some additional information to the compiler and JVM. This paper introduces the concept of Annotations in Java with an emphasis on various in-built annotations in Java and the annotations that are used by other annotations. The reader is introduced to J2EE standard annotations and those employed by Hibernate as a replacement for XML-based mapping document. Steps in designing and using custom annotations are highlighted. A custom annotation design is illustrated with the help of an example for execution of DML commands in a generic way in a database management system independent manner

Struts, Hibernate and Spring Integration ? A Case Study

Over the last few decades software development has undergone tremendous radical changes in order to enhance user experience, user friendliness and to widen its scope over large geographical area. The key actors in this arena are two leading IT companies Microsoft and Sun Microsystems, now taken owner by Oracle Inc. who compete on a continual basis for rendering rapid professional software design and development process at the same time incorporating more functionality and focusing strongly towards software maintenance issues. Due to this intense competition, the ultimate beneficiary is a software developer who is tremendously benefited at large. In this review paper, the researcher aims at consolidating the technological advancements that have brought a revolutionary change in corporate software development over last few decades. The main substance of the paper is technological advancements facilitating J2EE application development viz., struts framework, hibernate and spring framework which operate in different layers of scalable N-tier architecture. Each technology has its own merits and de-merits. The researcher attempts to aggregate the benefits offered by the trio in a single J2EE application thereby bringing in best of three worlds to a single application. The application is boosted with powerful struts tag library, persistent layer provided by hibernate and dependency injection or Inversion of Control (IoC) user the same roof. A case study is presented to demonstrate the integration of three diverse technologies, struts, hibernate and spring. JBOSS application server is employed as a container for J2EE components

On the origin of the various types of radio emission in GRS 1915+105

We investigate the association between the radio ``plateau'' states and the large superluminal flares in GRS 1915+105 and propose a qualitative scenario to explain this association. We identify several candidate superluminal flare events from available monitoring data on this source and analyze the contemporaneous RXTE pointed observations. We detect a strong correlation between the average X-ray flux during the ``plateau'' state and the total energy emitted in radio during the subsequent radio flare. We find that the sequence of events is similar for all large radio flares with a fast rise and exponential decay morphology. Based on these results, we propose a qualitative scenario in which the separating ejecta during the superluminal flares are observed due to the interaction of the matter blob ejected during the X-ray soft dips, with the steady jet already established during the ``plateau'' state. This picture can explain all types of radio emission observed from this source in terms of its X-ray emission characteristics.Comment: Corrected typo in the author names, contents unchanged, accepted in Ap