Erbug Celebi

A watermarking algorithm based on chirp z-transform, discrete wavelet transform, and singular value decomposition

Digital watermarking has attracted increasing attentions as it has been the current solution to copyright protection and content authentication which has become an issue to be addressed in multimedia technology. This study introduces a novel watermarking scheme based on the discrete wavelet transform (DWT) in combination with the chirp z-transform (CZT) and the singular value decomposition (SVD). Firstly, the image is decomposed into its frequency subbands by using 1-level DWT. Then, the high-frequency subband is transformed into z-domain by using CZT. Afterward by SVD, the watermark is added to the singular matrix of the transformed image. Finally, the watermarked image is obtained by using inverse of CZT and inverse of DWT. This algorithm combines the advantages of all three algorithms. The experimental result shows that the algorithm is imperceptible and robust to several attacks and signal processing operations.

Turkish — English cross language information retrieval using LSI

This paper describes a study of Turkish-English cross language information retrieval (CLIR) system. One of the biggest issues with CLIR studies is to access to bi-lingual parallel corpus. So, the first step of this study was to construct a parallel Turkish-English corpus. We have constructed a corpus that has 1801 parallel documents. The corpus has been divided in to two parts, first one for training the system and second one for testing the system. Latent semantic indexing (LSI) techniques applied to the training set to obtain the language relations. After the training, we have performed set of tests (queries) to measure the effectiveness of LSI based retrieval on Turkish-English parallel corpus. Our experimental results show that, LSI based CLIR outperforms the non-LSI based retrieval where their retrieval successes are %69 and %26 respectively.

Hybrid technique for robust image watermarking using discrete time fourier transform

The current paper proposes a novel scheme for non-blind watermarking of images, making use of discrete wavelet transform (DWT), discrete time Fourier transform (DTFT), as well as singular value decomposition, or SVD. During the process of embedding, 1-level DWT is used to decompose the host image into its various frequency sub-bands. After this, the high-frequency sub band receives an application of DTFT. This is followed then by SVD, after which the watermark becomes embedded into the now-transformed host images singular matrix. Then, the inverses of 1-level DWT, DTFT and SVD are applied in order to obtain a watermarked final image. This paper evaluates the performance of the proposed method of watermarking against a number of attacks, including sharpening, salt and pepper noise, AWGN, gamma correction, histogram equalisation, flipping and cropping. Results obtained during experiments have found that the scheme as proposed does provide high levels of robustness and imperceptibility against various signal processing attacks.

Miniarutized and lightweight automotive antenna design for vehicle to vehicle communication

In this paper, automotive antenna design for vehicle to vehicle communication is proposed. Antenna design is based on elliptical geometry by utilizing the self-similarity of the fractal concepts. The initiator is an elliptical shape based vertical to horizontal ratio of about 3:1. The proposed antenna is a combination of two reproduced elliptical shape placed at +/- 30 degrees to the central point of the initiator. Antenna is miniaturized (42 × 34 mm2) and lightweight with efficient characteristics. Simulation results show that the presented antenna has a reflection coefficient characteristic better than -17.5 dB, 70% radiation efficiency, 4-6dBi antenna gain and omni-directional radiation pattern properties over the 75 MHz of 802.11p standard (5.85 - 5.925 GHz).

Automatic question answering for Turkish with pattern parsing

In this study we have explained the implementation details of a Automatic Question Answering System for Turkish. Automatic Question Answering (QA) is a sub-field of information retrieval (IR) that deals with finding the answers of submitted free text questions. Automatic QA is important for daily life because, it retrieves the answers or answer sets of submitted questions without wasting time for searching the entire document corpus that include the answers. The important issue in QA systems is to extract the features of each sentence to create their semantic meaning. In this study, documents are processed with pattern matching techniques and features of documents are extracted for question answering system. We propose to categorize the questions automatically and then select the correct answer from corresponding answer set. We have used name entity recognition and pattern matching to categorize the type of questions. Additionally we have used range queries to submit the questions. Instead of using traditional distance metrics we have proposed a new approach to rank the similar documents. Each approach has been evaluated and described in this study.

Using Mobile Telephone as an Operator Independent, Secure Micro-Payment Tool

-With the latest advances in Information and Communication Technologies (ICT), using different technologies for electronic-payment has become a major issue in the retail market. The use of portable communication devices became particularly attractive candidates when versatility, security and simplicity features of payment technologies are considered.

Is BIG-5 personality feature set convenient for movie recommender systems

A recommender system is defined simply as the software tools or systems that recommend items like products, people, and service, to people based on the opinion of other similar preferences. BIG-Five is a widely examined theory of five broad dimensions used by some psychologists to describe human personality. The aim of this study is to analyze the possibility of a movie recommending system which benefits from users BIG-Five personality scores and personal details. The obtained data about people, their BIG-Five Scores and their preferences, are then analyzed using Classification, and results are evaluated. Results confirm that there is no relation between BIG-Five personality scores and movie type preferences.

The Effect of Stemming and Stop-Word-Removal on Automatic Text Classification in Turkish Language

Text classification is defined simply as the labeling of natural and unstructured language text documents using predefined categories or classes. This classification not only help organizations in improving their business communication skills and their customer satisfaction levels, but also improves the usage of unstructured data in academic and non-academic world. The aim of this study is to analyze the effect of stemming, over-sampling, and stopword-removal when doing automatic classification on Turkish content. After obtaning a Turkish Corpus, stemming, balancing, and stopword-removal is applied and the results are evaluated.

Classification of 20 News Group with Naïve Bayes Classifier

In this study, we have classified well known 20 News Group Set that contains 20.000 documents with a Naïve Bayes Classifier. Rather than using traditional Naïve Bayes method, we have used logarithm based classifier that is more suitable for information retrieval tasks. We successfully evaluated the performance of our implementation using two other classification studies (Icsiboost-bigram and EM) on the same dataset. The performance was measured by comparing its with the accuracies of other algorithms using the same dataset. We conclude that the Naïve Bayes Classifier performs well among other similar classifiers but it also has its short comings as well.

Kapsama katsayisi tabanli kümeleme ile belge özetleme

Multimedia documents, especially the text documents are occupying an important time in our daily life. Reading the summery of documents will allow us to spend less time and understand the document faster. A sumary consist of the subset sentences of documents and theyneeds to cover the main content of document as a brief.