Security of valuable multimedia contents such as images in personal photograph albums, electronic publishing, frames of multicast video conference can be achieved by image encryption. Secure transmission of these contents is required to be rapid, efficient and practical. Hence, image encryption process must be chosen not only to satisfy the security goals but also to fulfill these requirements. Due to the inadequacy and inefficiency of conventional text based information encryption methods, researchers have proposed several encryption schemes. Many of them are based on chaotic algorithms. Recently, the studies are concentrated on some weaknesses of chaotic algorithms and most of the presented solutions came up with complex structured chaotic maps. In this paper, we present a self-diagonal shuffler mechanism embedded to one dimensional chaotic encryption system to overcome its leak points while keeping simplicity and efficiency properties.

Günümüzde toplumlar sosyal, ekonomik ve kültürel yönden sürekli deðiþip geliþmektedir. Bu geliþim ve deðiþmeye neden olan etkenlerin baþýnda kuþkusuz teknoloji gelmektedir. Teknolojinin özellikle eðitime saðladýðý imkanlar ile bu geliþim hýz kazanmaktadýr. Son yýllarda eðitim teknolojisinin hýzlý bir þekilde ilerlemesi eðitim-öðretimde bilgisayarlarýn kullanýlmasýna neden olmuþtur. Bilgisayarlarýn saðladýðý görsel ve iþitsel desteðin özellikle okul öncesi çaðdaki çocuklarýn öðrenmelerinde etkili olacaðý bir gerçektir. Ama okul öncesi dönemde, çocuklarýn okuma yazma bilmemeleri ve küçük kas geliþimlerinin tamamlanmamýþ olmasý bu süreçte bilgisayar kullanýmýný sýnýrlandýrmaktadýr. Ancak teknolojinin sunduðu imkanlardan biri olan konuþma tanýma teknolojileri, bu sýnýrlýlýklarýn aþýlmasýna çözüm oluþturmaktadýr. Konuþma tanýma teknolojileri mikrofon vb. cihazlar tarafýndan algýlanan sesin bilgisayarlar tarafýndan tanýnmasýna yönelik geliþtirilen sistemlerdir. Bu çalýþmada konuþma tanýma teknolojisinin sunduðu imkanlar ile okul öncesi eðitimde çocuklarýn bireysel öðrenmesine destek vermek amaçlanmýþtýr. Bu amaç doðrultusunda, okul öncesi dönemde kullanýlmak üzere konuþma tanýma teknolojisinin entegre edildiði bir eðitim yazýlýmý hazýrlanmýþtýr. Bu yazýlýmýn en belirgin özelliði, tamamen ses ile kullanabilmesidir. Böylece elini, kolunu kullanamayan ya da bu organlarý olmayan çocuklar da yazýlýmý rahatlýkla kullanabileceklerdir.

Nowadays communities are continuously evolving and changing socially, economically and culturally. Technology is certainly at the top of causative agent of development and change. The opportunities offered by technology especially in education accelerating this development. In recent years rapidly progress of training technology has led to use computers in education. It’s a fact that audio-visual support provided by computers is efficient in pre-school children’s education. But in pre-school period children don’t know how to read and write and haven’t completed their small muscle development, this fact limits the use of computers in the process. However, speech recognition technologies which is one of the opportunities offered by technology, is the solution to overcome this limitations. Speech recognition technologies are the systems, that developed for the recognition of sounds by computers are perceived by the devices like microphone. In this study with the facilities of speech recognition technology, supporting individual learning in pre-school education has been aimed. For this reason an educational software in which this technologies of speech recognition are integrated for the usage of pre-school education has been prepared. The most distinctive characteristic of this software is to be able to used with completely sounds. Thus, this software can be used easily by the children who can not to use their hands and arms.

Günümüzde, Ýnternet dünyasýnýn geliþimi ile bilgiye ulaþmak hýzlý ve basit bir hal almýþtýr. Bu devasa Ýnternet dünyasýnda istenilen bilgiyi bulabilmek için arama motorlarý geliþtirilmiþtir. Arama motorlarýnýn nasýl çalýþtýðýný bilmek aramalarýn daha etkili olmasýný saðlayacaktýr. Bu çalýþmanýn saðlayacaðý sonuçlar ile kullanýcýlar bilgilere daha hýzlý ulaþabilirler. Bunun yanýnda araþtýrmacýlar, arama motorlarý tarafýndan saðlanan sonuçlarý daha iyi yorumlayabilirler. Bu çalýþmada, arama motoru Bing’in Ýngilizcedeki tekil-çoðul kelimeler için dokümanlarýn indeksleme algoritmasý tahminlenmeye çalýþýlmýþtýr. Bunun için öncelikli olarak incelenecek kelimeler seçilmiþtir. Bu kelimeler için sorgular oluþturulup, Bing’e gönderilmiþtir. Bing’den dönen sonuçlar analiz edilmiþtir. Bu sonuçlara göre, dokümanlar indekslenirken tekil-çoðul kelimeler için güçlü iliþkiler kurulduðu ve kelimenin kullaným sýklýðýnýn bu iliþkide etkili olduðu görülmüþtür.

Today, it has become really fast and easy to access information thanks to the developments in the internet world. Search engines have been developed to find desired information in this gigantic internet world. It is important to know how these search engines works so that searches are more efficient. This work provides results that could help end-users to access information faster. It could also help researchers to interpret results, provided by search engines, better. In this work we have tried to find the indexing algorithm of Bing for single-plural words. For this purpose, we first selected the suitable words and then send the constructed queries to the Bing. Afterwards, the returned results of the queries had been analyzed. We found out that there is a strong relation between single and plural form of the words in term of indexing by Bing. In addition, the frequencies of usage of the words also effect this relation.

Metaheuristic optimization algorithms are nowadays being employed to solve a wide variety of optimization problems. These algorithms are not based on mathematical evidence and have mostly been developed by imitation of natural phenomenon. In this study, a web-based educational metaheuristics testing tool was developed. With this tool, the users are able to test Artificial Immune System and Artificial Bee Colony algorithms on Benchmark functions, observe the results of optimization by modifying the parameters for each algorithm, and at the same time perform optimization procedures by typing their own functions with their own constraints. In addition, information on the working steps of both algorithms are provided in the application.

Bu makale birden fazla seviyede içiçe geçmiþliði mümkün kýlan çift zamanlý iliþkisel veri modelinin uygulanma araþtýrmasýný içerir. Zamansal veriyi betimlemenin temel yapýsý olan Çift Zamanlý Atom beþ bölümden oluþur; olay zamaný periyodu, bu verinin veri tabanýna iþlenme zaman dönemlerinin alt ve üst sýnýrlarý ve yeni veri deðeri. Çift zamanlý veri özniteliklerde bulunmaktadýr ve soyut veri tipi olarak uygulanmýþtýr. Ýçiçe geçmiþ çift zamanlý veri modeli yönetimi için örnekler, modelin özelliklerini göstermek için sorgulamalar sunulmuþtur. Örnek uygulama modelin yapýlabilirliðini göstermek için nesnesel-iliþkisel veri tabaný sisteminde tamamlanmýþtýr.

This paper presents an implementation of a nested bitemporal relational data model that allows more than one level of nesting. The fundamental construct for representing temporal data is a Bitemporal Atom (BTA) that consists of five parts: valid time period, the time periods’ lower and upper bounds this data is recorded in the database and a value. Bitemporal data is attached to attributes and applied as an abstract data type. A number of examples of the management of nested bitemporal data model and queries to demonstrate the features of the model are provided. A prototype implementation has been completed in an object-relational database system to demonstrate the feasibility of the model.