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This paper presents a method for calculating optimum values of stabilizing proportionalintegral- derivative(PID) controller for interval plants using particle swarm optimization(PSO) technique. This method is based on plotting the stability boundary locus in the (Kp,Ki)-plane for fixed Kd and then compute the stability region of PID controllers. Once the stability region of Kp,Ki locus is obtained, the best possible PID controller parameters are computed using PSO technique. The proposed method has got advantages like, It does not require sweeping over the parameters and also does not need a linear programming to solve set of inequalities over existing methods. To show the efficacy of the proposed method, a typical unstable fixed coefficient and interval plant is considered and simulated in MATLAB.The simulation results obtained by the proposed method are successfully verified.

Ethics and ethical behaviors are the ancient concepts which their history goes back to human’s life; and minds of many researchers have been involved in. In this regard, various theories have been proposed. In the field of ethics, one of the theories has been considered by masters is Ethical Work Climate Model presented by Victor & Cullen (1987). This model is the basis of our study. We aim to clarify the influence of gender and marital status on ethical work climate. So we studied ethical work climate in Agriculture Jihad Organization of Qom among men and women and also married and unmarried persons. Findings show there is no significant difference among men and women in ethical work climate. But one of the components of this model has a significant difference among men and women; this component is Independence Ethical Culture. It means in comparison with women, men are more independent in decision making about what is right and what is wrong. Also we found that there is no significant difference in ethical work climate among married and unmarried persons.

The need for renewable energy sources is on the rise because of the acute energy crisis in the world today. India plans to produce 20 Gigawatts of Solar power by the year 2020, whereas we have only realized less than half a Gigawatt of our potential as of March 2010. Solar energy is a vital untapped resource in a tropical country like ours. The main hindrance for the penetration and reach of solar PV systems is their low efficiency and high capital cost. To maximize a photovoltaic (PV) system's output power, continuously tracking the maximum power point (MPP) of the system is necessary. Maximum power point tracking (MPPT) is a technique that grid tie inverters, solar battery chargers and similar devices use to get the maximum possible power from one or more solar panels. Solar cells have a complex relationship between solar irradiation, temperature and total resistance that produces a non-linear output efficiency known as the I-V curve. It is the purpose of the MPPT system to sample the output of the cells and apply the proper resistance (load) to obtain maximum power for any given environmental conditions. Maximum power point tracking (MPPT) algorithms provide the theoretical means to achieve the MPP of solar panels; these algorithms can be realized in many different forms of hardware and software.

In this paper, we consider the 2nth-order symmetric differential expressions with real-valued coefficients. We obtain a necessary and sufficient condition for the discreteness of the spectrum of 2nth-order self-adjoint differential operators.

TiO₂ Nanoparticles (TNPs) were prepared by sol-gel method using TiCl₄ as the precursor and propanol as the solvent. The sizes of TNPs were about 4 nm and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-Visible spectroscopy (UV-vis). The X-ray powder diffraction studying explains that all the prepared samples have pure anatase phase tetragonal system. The gas sensing properties of TNPs were also investigated. We prepared porous poly silicon in nano and micron pores size by chemical electrolysation method and deposited TNPs by vacuum system (electron beam gun) with 23 nm thickness on porous poly silicon by sandwich method. I-V, and C-f curves was plotted. Gas sensing of this sandwich device increased in presence of TNPs in comparing with porous poly silicon without TNPs at room temperature by CO₂ gas.

The Second World War that took place from 1939 to 1945 involved the people of British West Africa who fought on the side of their colonial masters, the British. However a positive change in British colonial policy engendered the set up of Asquith and Elliot Commissions that favoured the establishment of institutions of higher education in some of the colonies in the post-war years. In this regard, the war was a catalyst to the emergence of university colleges in Gold Coast (now Ghana) and Ibadan in Nigeria. The British Labour Party government’s welfare scheme for the colonies and nationalists demand for higher education were also factors that made university colleges to develop and they were affiliated to the University of London. They maintained a high standard quality of education. Data for this discourse were generated from secondary sources.

The validity of equation-of-state (EOS) of geophysical minerals is very important for various scientific fields including geophysics, material science and high-pressure physics. In the present work we have calculated pressure , isothermal bulk modulus , first pressure derivative of isothermal bulk modulus and second order pressure derivative of isothermal bulk modulus in terms of for MgO and Al2O3, using different equation of state. Using the values of these parameters we have computed the values of Gruneisen parameter ( ) corresponding to different values of V/V0 and graphs are plotted for Gruneisen parameter ( ) vs. v/v0 for MgO and Al2O3. From these plots it is clear 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.

By adopting a language-oriented, problem-solving perspective, the present paper investigated the effect of grammatical proficiency on translation quality when translating English indirect speeches into Persian and the methods Iranian translators use to translate such a structure. A null hypothesis was formulated and 30 MA translation studies students were randomly chosen to take part in two tests: advanced grammar and translation test. A correlation test was used to determine the degree of go-togetherness between the two sets of scores. The result (rXY=0.824) rejected the null hypothesis, indicating a strong positive relationship between the two variables. Also, by analyzing translations, translated indirect speeches were categorized into five classes: Censorship, Lexical Translation, Free Translation, Direct Translation and Correct Translation. Finally, a simple model for translating English indirect speeches was proposed. The result indicates a gap in participants’ English knowledge which requires further studies to investigate the reason behind this shortcoming in Iranian context. The proposed model can be used in forming problem-solving curriculums for translation courses and further research is needed to cover other aspects in this respect.

The aim of this study was to investigate the adolescent psychopathologies among youth in Eldoret town. The objectives of the study were; to investigate the psycho-physical manifestations of psychopathology among youth in Eldoret town, the etiological factors in the psychopathologies and the relationship between the psychopathology and socio-economic factors. The study adopted the expost-facto research design. The study sample was 72 adolescents from low socio-economic status estates of the town which include Langas, Kamukunji, Kambi Nyasi, Munyaka, King’ong’o and Huruma estates. The common psychopathologies were aggression, anxiety disorders, depression, learning disorders, eating disorders and the conduct disorders. The etiological factors for the psychopathologies were peer influence, bad role models, influence of the environment and genetic factors. The psychopathologies were common in large families that that had five or more children implying laxity in control by the parents. The prevalence of the psychopathologies was high in less well-to-do families as well as those that had uneducated parents.

Current perspectives on the early childhood curriculum stress the need for a play-based program for children. Although the status of play has been given due to emphasis in the Malaysian Preschool National Curriculum, the implementation of play in the daily practice may not be consistent with the curriculum guidelines. Therefore, this study set out to examine the preschool teachers’ perception on the implementation of play in the private preschools. This study adopts the survey method, involving 105 teachers from 35 private preschools in Tampoi and Skudai, Johor. The questionnaire comprised of 46 items modified based on the CIPP model with the focus on the Input and Process constructs. Data were analyzed using descriptive analysis (mean, rank and standard deviation). Results on input evaluation revealed that although the teachers viewed play positively, they perceived possessing only average pedagogical knowledge about the implementation of play. On the other hand, the respondents believed that parents’ attitude towards the play concept was averagely positive. The overall appropriateness and availability of resources were also rated average. As for the process evaluation, the aspects of play management and the observation of the children’s behaviors were claimed to be average. A few suggestions were highlighted in the end of the study to enhance the effectiveness of the implementation of play in preschool curriculum.