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The main purpose of this study is to analysis the thermomechanical behavior of the dry contact between the brake disc and pads during the braking phase. The thermal-structural analysis is then used coupling to determine the deformation and the Von Mises stress established in the disc, the contact pressure distribution in pads. The results are satisfactory when compared with those of the specialized literature.

This paper examines the availability and variations of timber species within Ibadan Metropolis and Oyo Town Oyo State, Nigeria. Sixty copies of structured questionnaire were randomly administered on timber sellers from randomly selected timber markets in Ibadan and Oyo town. The selected markets in Ibadan were Bodija Timber Market (18), Sango Timber Market (12), Oke-Ado Timber Market (7) and Apata Timber Market (7). Those visited in Oyo were Sabo Timber Market (5), Owode Timber Market (6) and Oroki Timber Market (5). Descriptive statistics such as frequency and percentage distributions were used to analyze the collected data. Study revealed that 70% of the timber dealers were between 30 and 70 years of age, with 60% of them having been in business for more than 40 years. Various reasons were given by the traders on why they engaged in the timber business and these include availability, durability and demand, with majority (38.3%) of them citing the demand for the timber species as the reason why they traded the species. It was discovered from the study that certain timber species have become endangered species due to over- exploitation and these include Nauclea dideriichii, Tectona grandis, Terminalia spp., Khaya senegalensis Milicia excelsa, among others. The scarcity of these fine quality species has then brought into the market species in a few years ago were considered only suitable for low-end uses. These include Daniella oliveirii Pycnanathus angolensis(Akomu), Albizia zygia(Ayunre) and others. Therefore, there a is need for the planting of fast growing plantation species by State forestry departments in six geopolitical zones in Nigeria, as a replacement for commercially popular species; and as alternatives to decreasing availability of popular timber species so as to avoid running out of valuable and good quality timber species in the nearest future.

The density (?), viscosity (?) and ultrasonic velocity (U) have been measured for the binary mixtures of Brompheniramine with 1-Butanol at 303,308 and 313K. From the experimental data, several acoustic parameters such as adiabatic compressibility (?), free length (L_f), free volume (V_f), viscous relaxation time (?) and Gibbs free energy (?G) have been calculated. The excess values of the above parameters (?^E, L_f^E, V_f ^E ,?^E and ?G^E ) were also determined and interpreted in terms of molecular association such as hydrogen bonding formed between the liquid mixtures. The results show that hetero association and homo association of molecules decrease with increase in the temperature.

The validity of equation-of-state EOS of relevant materials is very important for various researchers in the scientific fields including geophysics, material science and high-pressure physics. In the present work we have calculated pressure , isothermal bulk modulas , first pressure derivative of isothermal bulk modulus and second order pressure derivative of isothermal bulk modulus in terms of for geophysical Olivine mineral, using different equation of state. Using the values of these parameters, we have computed the values of Gruneisen parameter ( ) and the graphs are plotted between V/V0 and Gruneisen parameter corresponding to different values of V/V0 for Olivine. From graph we observe that as V/V0 , goes to infinity. Isothermal bulk modulus increases continuously with increase in pressure. Pressure derivative of isothermal bulk modulus KT i.e. decreases progressively with the increase in pressure and is always negative. The result analysis conclude that the Brennan-Stacey and Shanker EOS is compatible both low and high compression ranges for calculating Gruniesen parameter where as Vinet EOS is not compatible for calculating the Gruniesen parameter at low compression ranges.

Many chronic acute diseases affect the respiration of the patients. The monitoring of vital body signs such as respiration is becoming increasingly important, especially in view of the general aging of the population and the associated increase in chronic diseases. A quantitative, semi quantitative or even qualitative monitoring of respiration may help to detect pulmonary disorders such as apnea, Cheyne – stokes or Biot’s respiration. When used in a home setting, respiratory monitoring should be easy to use and not constrictive to for the patient. Moreover, because longtime monitoring entails direct connection between the patient and the system, the integration of such systems into clothing is desirable. A novel approach is presented for non constrictive long term – monitoring of respiration, which could particularly become suitable for home care applications. The system is based on textile integrated force sensors, which detect expansion of the thorax during respiration and allow wireless data transmission for maximum mobility. Possible application include long - term monitoring of patients with chronic pulmonary diseases, early recognition of disease and the performance measurement of athletes during excise. Results from performance tests under various conditions are presented. In addition, long – term respiratory monitoring systems could be used to monitor the performance of athletes and to optimize their training. Many qualitative, quantitative and semi – quantitative methods that are integrated in clothing for respiratory monitoring are available.

English, Kurdish, and Persian belong to Indo-European languages and they have the same proto form so they are called related (family) languages. As these languages have the same common ancestor, it is clear that they have some similar linguistic items regarding syntax, semantics, morphology, pragmatics, etc. But as they are spoken in different distinct areas, they may have some differences regarding these items. One of these linguistic items is grammatical aspect. This study was conducted to define and describe the concept and function of grammatical aspect in languages like English, Kurdish, and Persian to find if there were any similarities and differences among them. To do this, first the notions of aspect, tense, and time and also the difference between grammatical and lexical aspect were defined clearly. Then grammatical aspect was defined and described in each language by drawing separate tables. At the other part of the article, I compared grammatical aspect in three languages and found that there were some similarities and differences among these languages concerning grammatical aspect. Finally, the article concluded with making some conclusions and recommendation for those who want to learn these languages as second or foreign language. I hope this study can help the learners and teachers in facilitating the process of teaching/learning, and so do for translators and researchers to do their work better.

In this work, an attempt was made to synthesize chalcones 3-(Substitutedphenyl)-N-(4H-1,2,4-triazol-4-yl)acrylamide by condensation of Substitutedbenzaldehyde with N-(4H-1,2,4-triazol-4-yl)acetamide under basic conditions by using both conventional and Microwave synthesis methods. A simple condensation reaction of substiutedbenzaldehyde and N-(4H-1,2,4-triazol-4-yl)acetamide using Sodium hydroxide as a base was carried out for the study. The synthesized chalcone derivatives were characterized for FTIR, 1H NMR, 13C NMR and Mass spectral analysis. It was observed that complete conversion to chalcone occurred in 10-12 min by Microwave synthesis method and in 10 h by conventional method. Finally, it has been observed that chalcone synthesis using Microwave synthesis method is a Convenient, Rapid and Eco-Friendly Synthesis over conventional method. The reaction time has been brought down from hours to seconds with improved yield as compared to conventional heating.

With the progress of VLSI technology, delay buffer plays an important role affecting the circuit design and performance. This paper presents the design of low power buffer using clock gating and gated driver tree. Since delay buffers are accessed sequentially, it adopts a gated clock ring counter addressing scheme. The ring counter employs double edge triggered (DET) flip flops instead of traditional flip flop to half the operating frequency. Also for generating clock gating signals, combinational elements (C-element) are implemented in the control logic to avoid the increasing loading of the global clock signal. For the clock distribution network, a gated driver tree technique is used and it further reduces the power consumption. In addition, this technique is used in the input and output ports of the memory to decrease their loading. The proposed delay buffer consumes less power comparing to the conventional delay buffers.

Due to the rapid development of internet, perfect copy and illegal use of digital data becomes easy, which enforces the newer mechanism to provide means of protecting all forms of digital data. The purpose of this paper is to propose a novel approach of protecting the ownership rights and resolving the dispute of unauthorized addition of second watermark on already watermarked data by the use of watermark authentication server (WAS). Watermark authentication server serves as a trusted third party and solves the problem of deadlock in watermarking.

The success of a machine learning algorithm depends on quality of data .The data given for classification, should not contain irrelevant or redundant attributes. This invariably increases the processing time. The data set, selected for classification should contain the right attributes for accurate results. Feature selection is an essential data processing step, prior to applying a learning algorithm. Here we discuss some basic feature selection models and evaluation function. Experimental results are compared for individual datasets with filter and wrapper model.