Volume-4 , Issue-9 , Sep - 2016 Go Back

The aim of this research work is to study the security issues in the Web learning environment. Problems in Web learning system are related to networking issues, database management issues, operating system related issues, memory and sharing issues, resource channeling issues, learners� authenticity related issues, load related issues, virtualization-related issues, management information system, etc., These above said issues are very common and hurdle in Web learning environment. From Web service providers to learners there are many possibilities in security lapse. The service providers have possibilities to control the system, but controlling the flow of information and controlling the technology such as networking and database usage, virus and information related laws are difficult to manage. There are possibilities to control the flow of information from every stage from the main service provider to users. Data losses can be minimized by maintaining the local backups separately. By developing the infrastructure, a service provider can facilitate the communication between the learner and the educator. Storing the sensitive data in a secured place is the best method to save. Storing the important data in the Web has a potential risk. This review paper critically analyzes the various issues related to Web security

Web learning, Web computing, Security, Network, Web security issues, Data loss, Information laws, Backups

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N. Jebaseeli, L. Jayasimman, B.S. Kumar, "Enhancing Web Security Based on Network Algorithm," International Journal of Computer Sciences and Engineering, Vol.4, Issue.9, pp.138-140, 2016.

Every organization faces the issue of slow performance with their database on regular basis. In this scenario, a DBA is required to tune the database or find the root cause of the sluggishness. Tuning a database after it has been setup is a highly tedious task and requires a lot of expertise, in-depth knowledge of the architecture and underlying functionality. So, it�s better to deal with the problem from the starting, i.e. structuring the Database in such a manner, that it yields good performance. This will make the database more stable and reduce the effort required to manage the database. So, presented below is a method to achieve better performance regardless of the quality of the hardware on which the database is hosted. Below method of database structuration made my life easier when I was asked to design the structure of an organization�s database from scratch and this entire paper is based on that method.

Database Optimization, Database Structuration, Performance Tuning, Table Structuration

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A. Sharma, "Tuning a Multi-Million Row Table," International Journal of Computer Sciences and Engineering, Vol.4, Issue.9, pp.141-145, 2016.

The data preprocessing is helpful in removing noise, inconsistency in the given data and produce quality data. The output of the data preprocessing is then given to refinement of existing algorithm that can later applied over the data structures called external sorting, optimal binary search trees, and pattern matching algorithms. In external sorting(first case), user data entered can be qualified using Data preprocessing, then separate algorithms used to different data items such as numeric and alphabets. In Optimal binary search trees (second case), user entered data can be made quality data using data preprocessing (second case), then refined algorithm used over the data elements that produce OBSTs separately for numeric items, and String items. In pattern matching (third case), user entered data can be made quality data, then refined algorithm used over the text which immediately finds out index for the pattern along with history of indices for the substring which further helpful in manual identification of the given pattern in the large given text. The results and graphs were also demonstrated based on certain examples. This also differentiates between time complexities obtained of the existing and proposed algorithm used over the data structures such as external sorting, OBST, and pattern matching.

Data preprocessing, data structures, external sorting, Optimal Binary Search Trees, Pattern Matching, Time Complexities

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S.H. Raju, M.N. Rao, "A Review on Specific Data Structures Using Data Preprocessing and Refinement of Existing Algorithms in Order to Improve Time Complexities," International Journal of Computer Sciences and Engineering, Vol.4, Issue.9, pp.146-151, 2016.

Anisotropic Diffusion is very efficient non-linear image processing PDE based technique which simultaneously restore images and enhance image features for 2-D or, 3-D images. This technique is described by local eigenvalues and local eigenvectors of the anisotropic diffusion tensor field where anisotropic diffusion coefficients are depending on direction and position. Here, mathematical analysis of robust anisotropic diffusion (RAD) filter for ultrasound (US) image has been discussed in this paper. It includes probabilistic memory mechanism and speckle statistics models of tissues characterization and adapts the anisotropic diffusion tensor to the ultrasound image iteratively. Higher frequency absorbed by tissue and skin but cannot penetrate deeply in comparison to lower frequency which give poorer image quality by echo signals, so we get an inferior quality image with some clinical information loss. This clinical information loss is restored by iterative process of various state-of-the-art filters, but discussed RAD filter shows better performance in terms of measured MSE and SSIM index, with including memory mechanism and speckle statistics, and preserves the relevant tissue details for clinical purposes.

Ultrasound imaging, speckle filter, anisotropic diffusion, tensor, Volterra equations.

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S. Kushwaha, "Mathematical Analysis of Robust Anisotropic Diffusion Filter for Ultrasound Images," International Journal of Computer Sciences and Engineering, Vol.4, Issue.9, pp.152-160, 2016.