Research ArticleOpen accessIn the abstractA New Semantic Cache Management Method in Mobile DatabasesShengfei Shi, Jianzhong Li, Chaokun WangIn mobile database systems, caching is a crucial way to improve the performance because a new query can be partially answered locally when the client is continuously moving around. Semantic caching has been paid much attention in traditional database systems. However, the methods of semantic cache management proposed in those systems are not suitable for mobile computing environment. Moreover, although … …Journal of Computer Science, Vol. 1, Issue 3 · 30 Sep 2005 · 6,882 accessesView PDFCite
Research ArticleOpen accessIn the abstractOn the Stability of a Certain Class of Linear Time-Varying SystemsM. De la SenThis study firstly considers the exponential stability of unforced linear systems of slowly time-varying dynamics. Possible switchings of the system structure to unstable dynamics during certain finite time intervals are admitted. The maintenance of global exponential stability does not necessarily require at most a finite number of switchings in the dynamics while infinitely many switches can also lead to stability. … …American Journal of Applied Sciences, Vol. 2, Issue 8 · 31 Aug 2005 · 6,937 accessesView PDFCite
Research ArticleOpen accessIn the abstractFormation of Optimal Messages Path Delivery Within a Virtual Channel TechnologyH. Al-Bdour, K. KaabnehThis research study deals with the process of reduction and optimization of data transmission delays in mobile Internet networks during mobile subscriber transmission (SsS) to various coverage areas. The methods for information transmission in IP-networks and networks based on virtual channel technology are investigated. Throughout this research, special attention is given to the analysis of existing methods for channel reconfiguration … …Journal of Computer Science, Vol. 1, Issue 2 · 30 Jun 2005 · 6,538 accessesView PDFCite
Research ArticleOpen accessIn the abstractMathematical Model of 4-Quadrant DC Electric Drive with 6-Pulse Dual ConverterKosmas ZdrozisMathematical model simulating the operation of DC electric drive hoisting mechanism has been developed. The study illustrates the capabilities of the developed model for investigation both normal and abnormal modes of operation of the converter and the supplying voltage. Large attention was given to the thyristor converter and its firing system so that fast-proceed micro-processes occurring in the converter can … …American Journal of Applied Sciences, Vol. 2, Issue 5 · 31 May 2005 · 7,002 accessesView PDFCite
Research ArticleOpen accessIn the abstractUltra Wide Band (UWB) Ad-hoc Networks: Review and TrendsRashid Saeed, Sabira Khatun, Borhanuddin M. Ali, Mohd K. AbduallahShort-range wireless systems have recently gained a lot of attention to provide seamless, multimedia communications around a user-centric concept in so called Wireless Personal Area Networks (WPAN). Ultra-Wide Band (UWB) technology presents itself as a good candidate for the Physical Layer (PHY) of WPAN, both for high and low data rate applications. Many ongoing developments of Ultra-Wide Band (UWB) system … …Journal of Computer Science, Vol. 1, Issue 1 · 31 Mar 2005 · 7,063 accessesView PDFCite
Research ArticleOpen accessIn the abstractAn Investigation into the Use of the Least Significant Bit Substitution Technique in Digital WatermarkingKevin Curran, Xuelong Xi, Roisin ClarkeDigital imaging companies lose revenue each year to people who are illegally copying and using their images. One prevention mechanism is to digitally encode images making it difficult for others to copy. This could be done using digital fingerprinting or simply adding a visible watermark. The information is hidden in a way that should not attract attention, but make it … …American Journal of Applied Sciences, Vol. 2, Issue 3 · 31 Mar 2005 · 7,471 accessesView PDFCite
Research ArticleOpen accessIn the abstractWind Speed Simulation Using WaveletsA. H. Siddiqi, S. Khan, S. RehmanMost of the renewable energy sources have direct or indirect link with the sun. Wind is also a form of solar energy. It is initiated by uneven heating of the atmospheric air by the sun, affected from the topography and surface roughness of the earth's surface and rotation of the earth. The earth's terrain, water surfaces and vegetation cover modifies … …American Journal of Applied Sciences, Vol. 2, Issue 2 · 28 Feb 2005 · 7,553 accessesView PDFCite
Research ArticleOpen accessIn the abstractDuration Modeling in Undergraduate Econometrics Curriculum via ExcelIsmail H. GencThe main goal of an Econometrics course is to prepare students for more advanced levels of study and make them able to cope with the empirical problems they are likely to face. In recent years, there has been a tendency to purge merely theoretical topics from the econometric textbooks by including only time honored methods. Survival analysis, however, has so … …American Journal of Applied Sciences, Vol. 1, Issue 4 · 31 Dec 2004 · 7,055 accessesView PDFCite
Research ArticleOpen accessIn the abstractAn Investigation of the Nature Properties of PlasmaPeter Evans, Frederick Osman, Heinrich HoraThis study presents the characteristics of the plasma and the effect of the laser beam to best suit the plasma model behavior. Special attention is paid to the “Genuine” Two Fluid Model and the ponder-motive and transient forces. These models are translated into a numerical study of the parameters, such as the electric field density and temperature distributions once electromagnetic … …American Journal of Applied Sciences, Vol. 1, Issue 3 · 30 Sep 2004 · 6,568 accessesView PDFCite