Scala Server Faces

Progress in the Java language has been slow over the last few years. Scala is emerging as one of the probable successors for Java with features such as type inference, higher order functions, closure support and sequence comprehensions. This allows object-oriented yet concise code to be written using Scala. While Java based MVC frameworks are still prevalent, Scala based frameworks along with Ruby on Rails, Django and PHP are emerging as competitors. Scala has a web framework called Lift which has made an attempt to borrow the advantages of other frameworks while keeping code concise. Since Sun’s MVC framework, Java Server Faces 2.0 and its future versions seem to be heading in a reasonably progressive direction; I have developed a framework which attempts to overcome its limitations. I call such a framework ―Scala Server Faces‖. This framework provides a way of writing Java EE applications in Scala yet borrow from the concept of ―convention over configuration‖ followed by rival web frameworks. Again, an Eclipse tool is provided to make the programmer\u27s task of writing code on the popular Eclipse platform. Scala Server Faces, the framework and the tool allows the programmer to write enterprise web applications in Scala by providing features such as templating support, CRUD screen generation for database model objects, an Ant script to help deployment and integration with the Glassfish Application Server

MongoDB Performance In The Cloud

Web applications are growing at a staggering rate every day. As web applications keep getting more complex, their data storage requirements tend to grow exponentially. Databases play an important role in the way web applications store their information. Mongodb is a document store database that does not have strict schemas that RDBMs require and can grow horizontally without performance degradation. MongoDB brings possibilities for different storage scenarios and allow the programmers to use the database as a storage that fits their needs, not the other way around. Scaling MongoDB horizontally requires tens to hundreds of servers, making it very difficult to afford this kind of setup on dedicated hardware. By moving the database into the cloud, this opens up a possibility for low cost virtual machine instances at reasonable prices. There are many cloud services to choose from and without testing performance on each one, there is very little information out there. This paper provides benchmarks on the performance of MongoDB in the cloud

Auto-generation of rich Internet applications from visual mock-ups

Capturing and communicating software requirements accurately and quickly is a challenging activity. This needs expertise of people with unique skills. Traditionally this challenge has been compounded by assigning specialist roles for requirements gathering and analysis, design, and implementations. These multiple roles have resulted in information loss mainly due to miscommunication between requirement specialists, designers and implementers. Large enterprises have managed the information loss by using document centric approaches, leading to delays and cost escalations. But documentation centric and multiple role approaches are not suitable for Small to Medium Enterprises (SMEs) because they are vulnerable to market competitions. Moreover, SMEs require effective online applications to provide their service. Hence the motivation for carrying out this research is to explore the possibilities of empowering requirement specialists such as Business Analysts’ (BAs) to take on additional responsibilities of designers and implementers to generate web applications. In addition, SME owners and BAs can communicate better if they perceive the application requirements using a What You See Is What You Get (WYSIWYG) approach. Hence, this research explores the design and development of mock-up-based auto-generating tool to develop SME applications. A tool that auto-generates an application from a mock-up should have the capacity to extract the essential implementation details from the mock-up. Hence a visual mock-up language was created by extending existing research on meta-models of UIs for a class of popular modern web-based business applications called Rich Internet Applications (RIAs). The popularity of RIAs is due to their distinctive client-side processing power with desktop application like responsiveness and look and feel. The mock-ups drawn with the mock-up language should have sufficient level of details to auto-generate RIAs. To support this, the mock-up language includes constructs for specifying a RIA’s mock-up in terms of layouts and the widgets within them. In addition, the language uses annotations on the mock-up to specify the behaviour of the system. In such an approach the only additional effort required of a Business Analyst is to specify the requirements in terms of a mock-up of the expected interfaces of the SME application. Apart from the mock-up language, a tool was designed and developed to auto-generate the desired application from the mock-up. The tool is powered by algorithms to derive the database structure and the client-side and server-side components required for the auto-generated application. The validation of the mock-up language and auto-generating tool was performed by BAs to demonstrate its usability. The measurement and evaluation results indicate that the mock-up language and the auto-generator can be used successfully to help BAs in the development of SME application and thereby reduce delays, errors and cost overruns. The important contributions of this research are: (i) the design of a mock-up language that makes it easy to capture the structure and behaviour of SME web applications. (ii) algorithms for automatic derivation of the expected database schema from a visual mock-up. (iii) algorithms for automatic derivation of the client and server-side application logic. (iv) application of an existing measurement and evaluation process for the usability testing of the mock-up language and the auto-generated application. This research followed the Design Science Research (DSR) method for Information System to guide the IS design and to capture the knowledge created during the design process. DSR is a research method useful in solving wicked problems requiring innovative solutions for incomplete, contradictory or changing requirements that are often difficult to recognize. This research opens new ways of thinking about web application development for future research. Specifically, mock-ups with few easy to understand annotations can be used as powerful active artifacts to capture the structure and behaviour of applications not just of small but also large enterprises. Auto-generating tools can then create fully functional and usable applications holistically from such mock-ups, thereby reducing delays and cost overruns during software engineering

Supporting formal expression of eligibility criteria in clinical trials. The implementation and evaluation of the eligibility criteria builder

A clinical trial is a study that assesses the effectiveness and safety of a new drug or treatment. To be able to generalize from the findings of the study, the clinical trial requires a representative sample of the target patient population. The target population is defined in terms of eligibility criteria that clearly describe the characteristics of patients enrolled in the study. The eligibility criteria are stated in natural language in its own section in a protocol document, which serves as the plan and detailed description of any prospective clinical trial. Having the eligibility criteria expressed as natural language has several drawbacks. First, it can lead to ambiguities and different interpretations among clinicians responsible for enrolment of patients into the study, which consequently may affect the safety of patients. Second, it provides no means of automatic eligibility checking against patient databases and electronic patient journals. The process of determining the eligibility of each patient therefore becomes a resource demanding and time consuming task. Formally defined computer interpretable eligibility criteria could potentially improve safety of involved patients and efficiency in patient enrolment. This thesis presents the Eligibility Criteria Builder that aims to provide a simple and pragmatic way of defining these rules using a user-friendly graphical user interface. The evaluation of the prototype indicated that the target users in general were positive to, and clearly saw the need for, a tool like this. The evaluation also pointed out weak spots and areas of improvements for the proposed prototype

Indexing and retrieval of free-form surfaces using self-organizing maps

This thesis describes the use of Self-Organizing Maps in combination with unique curvature based feature combinations and various training data sets as a clustering function to describe free-form surfaces. Our descriptor was successfully used as the basis of techniques that segmented, indexed and retrieved free-form surfaces represented as triangulated meshes