In this paper, English language will be used as an instance of natural languages as we will be concerned with the set of all natural language texts. this research tries to employ a set of all synonyms as a way to hide secret message inside a natural language text. 

Modeling of take-off and landing motion for a fixed wing (UAV) is necessary for developing an automatic take off and landing control system (ATOL). Automatic take off and landing system becomes an important system due to wide spread of unmanned aerial vehicles in different applications ranging from intelligence, surveillance, up to missile firing. Automatic take off and landing system reduces damage to an unmanned aerial vehicle and its payload that may be caused by human pilot errors. Furthermore, training human pilot to a sufficient level of skill and experience for takeoff and landing may take several years and significant cost. A human pilot also may impose additional restrictions for UAV operation especially at night time or dusty desert conditions. Although, ATOL adds complexity to the system, it reduces the long run cost and risk caused by takeoff and landing process, and makes UAV takeoff from different runways and at different atmospheric conditions. A mathematical model for takeoff is successfully developed for a small fixed wing UAV. A Matlab/Simulink simulation model is prepared for the ground roll phase, and some simulation results are also shown.

The aim of this work was to determine TTT diagram of medium carbon V-N micro-alloyed steel with emphasis on the

development of intragranular ferrite morphologies. The isothermal treatment was carried out at 350, 400, 450, 500, 550

and 600 οC. These treatments were interrupted at different times in order to analyze the evolution of the microstructure.

Metallographic evaluation was done using optical and scanning electron microscopy (SEM). The results show that at high

temperatures (≥ 500 ○C) polygonal intragranulary nucleated ferrite idiomorphs, combined with grain boundary ferrite and

pearlite were produced and followed by an incomplete transformation phenomenon. At intermediate temperatures (450, 500

○C) an interloced acicular ferrite (AF) microstructure is produced, and at low temperatures (400, 350 ○C) the sheave of

parallel acicular ferrite plates, similar to bainitic sheaves but intragranularly nucleated were observed. In addition to sheaf

type acicular ferrite, the grain boundary nucleated bainitic sheaves are observed.

The electron-doped magnetic nanoparticles of Ca1–xYxMnO3 (x = 0, 0.05, 0.10, 0.15, 0.20,

and 0.30) manganite with an average particle size of 50 nm are analyzed and discussed in relation to their bulk counterparts. Nanoparticle samples show dominant anti-ferromagnetic ordering with a significant increase of coercivity, with the maximum value of 0.9 T for x = 0.

Par ti cle size re duction in Ca1–xYxMnO3 retains the bulk-like magnetic behavior of samples

having up to 15% of Y3+, with the small fer ro mag netic contri bu tion from dis or dered sur face

spins. Sup pres sion of charge order ing state and en hance ment of sat ura tion mag ne ti zation

were found in samples with higher Y3+ con cen tra tion (x = 0.2, 0.3), indicating high ferromag netic contri bu tion in these sam ples

This paper presents empirical methods for enhancing the accuracy of inductive learning systems. It addresses the problems of: learning propositional production rules in multi-class classification tasks in noisy domains, maintaining continuous learning when confronted with new situation after the initial learning phase is completed, and classifying an object when no rule is satisfied for it.

It is shown that interleaving the learning and performance-evaluation process allows accurate classifications to be made on real-world data sets. The paper presents the system ARIS which implements this approach, and it is shown that the resulting classifications are often more accurate than those made by the non-refined knowledge bases.

The core design decision that lies behind ARIS is that it employs an ordering of the rules according to their weight. A rule’s weight is learned by using Bayes’ theorem to calculate weights for the rule’s conditions and combining them. This model focuses the analyses of the knowledge base and assists the refinement process significantly.

The system is non-interactive, it relies on heuristics to focus the refinement on those experiments that appear to be most consistent with the refinement data set. The design framework of ARIS consists of tabular model for expressing rule weights, and the relationship between refinement cases and the rules satisfied for each case to focus the refinement process. The system has been used to refine knowledge bases created by ARIS itself, as well as to refine knowledge bases created by the RIPPER and C4.5 systems in ten selected domains.

Problem statement: In the construction industry, success of building projects greatly depends on the client’s performance. The performance of clients is crucial since decisions made will influence the overall project performance. Typically, clients are represented by managerial and technical representatives during the design process. They play major roles in conveying required information to the design team regarding their future project. The quality of clients’ representatives has potential influence on design team performance. In designing green buildings client’s attributes are critical factors to high performance of building projects. Attributes such as knowledge and experience on green buildings, commitment level to green and clients’ ability to participate and manage design process are the key factors to produce green design. The propose of this study to identify current performance level of clients of building projects and establish key clients’ attributes influencing green design performance. Approach: To achieve mentioned aim a questionnaire survey was conducted to collect dada required. A sample of 274 respondents has been covered under the study, including architects and engineers practicing design and consultancy building sectors. Prior to analysis of data WINSTEPS software were used for Rasch modeling to determine validity and reliability of date. Descriptive analysis data includes quantitative and qualitative. Results and Conclusion: Client qualities in general were low, client communication with design team; client involvement and ability to coordinate design process were moderate. However, Knowledge and experience on green …