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Pedagogical content knowledge (PCK) has become a framework for exploring what teachers need to know or to develop for effective teaching. Physics teachers’ PCK includes five components. In this study, the self-made “Questionnaire of Physics Teachers’ Pedagogical Content Knowledge” was used. The quantitative responses were compiled and analyzed by SPSS. The results indicated that the physics teachers’ level of PCK is on the intermediate and many factors help physics teachers to develop their PCK.

The marine micro organisms are the store house of a wide variety of biologically active products. Among the vast population of microorganisms which include algae, bacteria, actinomycetes etc., marine fungi are considered as the most useful microorganisms in biotechnology field. The marine environment conditions the micro flora to generate metabolites that have antimicrobial qualities as a self- defending mechanism. The objective of this paper was to isolate the Zinc resistant fungal strains from marine samples like wood , seashore sand , sea water and wooden boat and identify the isolated cultures morphologically till the genus level. The antimicrobial compounds were extracted using different organic solvents and their antibacterial activity was cheked on the selected pathogenic bacteria at different varying concentration. A confirmatory test was performed for each test organism in their selective media. The fungal cultures were found to belong to the genus Aspergillus, Mucor and Fusarium. The extracts of hexane and chloroform on mucor showed very good activity on E.coli while average activity on Pseudomonas aeruginosa and Klebsiella pneumonia and least activity in S. aureus cultures was found.

This paper presents the model which is developed for single and coupled microstripline structure for both the even and odd-mode of propagation of waves. Most important and common models are: Conformal transformation model, coupled analysis model, hybrid analysis model, numerical analysis by relaxation model, even and odd-mode models, which is the outcome of the coupled line model. H.A. Wheeler derived the characteristic impedance and propagation parameters. Numerical methods are adopted by Stenelhalfer and Sylvester based on pure TEM-mode, Quasi-TEM mode and Non-TEM mode

This paper aim to discuss the preliminary study of modelling algorithm setting of Stochastic Boosted Regression Trees (BRT) using R statistical software. The ground level ozone (O3) concentrations from a Malaysia’s air quality monitoring station was used as a case study. The new approach; BRT developed by Friedman (2001), Friedman (2002) and adopted by Yahaya (2013) in air pollution studies. BRT is differ substantially from traditional regression-based approaches. BRT are constructed of multiple regressions models which finally produce a single ‘best iteration’ model to optimize prediction performance. Sensitivity testing of model been carried out to determine the best parameters’ setting which are number of trees (nt) (1000-10000), learning rates (lr) (0.005-0.5), and interaction depth (tc) (1-10) to suits the ozone data. Results indicated that the BRT analysis algorithm best modeled with the best combination of parameters lr=0.001, tc=5 and nt=5301 that achieves minimum predictive error (minimum error for predictions). The algorithm model would crucially best provided clear benefit for air pollution study and their ability to model complex variable interactions and non-linear effects.

The aim of the study is to delineate the morphometric characteristics of Kangshabati-Darkeswar Interfluves Area using remote sensing and GIS technology. 10 km2 grids were elaborate to delineate the relief characteristics using Advance Space Thermal Emission and Radiometer (ASTER) data. Drainage networks were automatically extracted from digital aster elevation models. Second order local polynomial (LP) interpolation technique was used to estimate the surface characteristics of the study area using ArcGIS 9.3. The absolute elevation of the study region is extended between 4.0 – 949.29 m with an average elevation of 484.50m. The highest relative relief resulted 833.69m, whereas the average ruggedness index of the study area is recorded as 0.09 per 10 km2 area. The average drainage density of the study area was computed 0.73 /sq. km and the highest drainage intensity are recorded as 9.58/10 km2 grid area. The average length of overland flow of the study area was 2.56/10 km2 grid areas. The result of the study highlights an about the spatial distribution of relief and hydrological characteristics which may provide the knowledge to devise and accomplish an appropriate plan to progress agriculture and others allied activities. Hence, from the study, it can be concluded that remote sensing data (ASTER –DEM) coupled with GIS techniques prove to be a competent tool in morphometric analysis and the data can be used for basin or interfluves area management and other hydrological studies in future.

We are very happy to announce that from 24th August 2012, Mr. Dambaru Ballab Kattel has joined the team of Elixir Editorial Advisory Board. He will carry a special responsibility for dealing with manuscripts based on meteorology/climatology (particularly in the mountain climate system around Himalayas). Mr. Dambaru Ballab Kattel is currently associated with Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China. The appointment of Mr. Dambaru Ballab Kattel as member Editorial Advisory Board strengthens the links and will make it easier for prospective authors to establish contact with the journal. Please send any expressions of interest to chiefeditor@elixirjournal.org. Sincerely Editor-in-Chief

Power consumption of system level on chip communications is becoming more significant in the overall system on chip power as technology scales down. High bandwidth is desired to enhance parallelism for better performance, and the power efficiency on this bandwidth is critical to the overall SoC power consumption. Current bus architectures such as AMBA, Core connect, and Avalon are convenient for designers but not efficient on power. This paper proposes a physical synthesis scheme for on chip buses and bus matrices to minimize the power consumption, without changing the interface or arbitration protocols. By using a bus gating technique, data transactions can take shortest paths on chip, reducing the power consumption of bus wires to minimal. Routing resource and bandwidth capacity are also optimized by the construction of a shortest-path Steiner graph, wire sharing among multiple data transactions, and wire reduction heuristics on the Steiner graph. In this paper, we optimize on-chip bus communications on the tradeoffs between minimal power, maximal bandwidth, and minimal total wire length. Based on AMBA protocols, we modify the bus structure using a “bus gating” technique, and apply optimizations which are biased toward minimal power, but also favor bandwidth and routing resource.

Doubly fed induction generator (DFIG) based wind turbines have arisen as the leading technologies in wind power market as they offer a variable-speed, economically viable and efficient alternative to the fossil fuel. The present paper comprises of a wind energy conversion system which is simulated using two level pulse width modulation (PWM) converter as well as three level (PWM) converter and their performance under normal and fault conditions are compared. It is observed that multi-level inverters generate purer sinusoidal voltage with reduced total harmonic distortion thus bringing an improvement in the quality of generated power.

Seeds of Vigna aconitifolia Jacq.(mataki seeds) pre-soaked in cell free culture filtrate of post-harvest sapota fungi viz.Geotrichum candidum, Aspergillus niger and Rhizoctonia solani. Impact of effect of incubation period, pH and temperature on fungal metabolites from culture filtrates on seed germination was studied for toxicity. It is clear from the result that culture filtrate of all the post-harvest sapota fungi hampered percentage of mataki seed germination and showed reduction in root length and shoot length as compared to control.

The main objective of this paper is to find the optimum machining parameter for higher Material Removal Rate (MRR) in micro EDM on 316L stainless steel. The most important parameters like machining voltage, capacitance and sparkgap are considered in this experimentation. The experiments were conducted based on the full factorial design methodology. Multiple regression and Artificial Neural Network (ANN) techniques were applied to predict the MRR. The predicted results are quite closer with the experimental results. S/N ratio was calculated to find the optimum values. ANOVA is carried out and the influence of machining parameters was found. The results show that the voltage is highly significant and the capacitance is the next significant than sparkgap on MRR.