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Electric discharge machining (EDM) is a non-traditional machining processes that involved a transient spark discharges through the fluid due to the potential difference between the electrode and the work piece. In this experiment, EDM process on mild steel workpiece was conducted EDM Die Sinking Neu-ar. The electrodes used were copper, brass and graphite. This project is to be conducted using Taguchi method L4 orthogonal array. The parameters to be studied are peak current (12A and 21A), discharge ON time (10µs and 45 µs) and pumping direction (B0 and B1). This research aims to study the factors that influencing the machining of different electrodes in electrical discharge machining (EDM) process. Surface roughness was measured using surface roughness tester (SJ-301). Material removal rate (MRR) and electrode wear ratio were determined based on weighting the workpiece and electrode using digital weight scale. Then, the result of the experiment was analyzed by using EXCEL. The higher material removal rate in the EDM machine, the better is the machining performance while the lower electrodes wear ratio in the EDM machine is the better and accurate performance characteristic. The results show that copper electrode gives higher material removal rate which is 0.411 g/min than brass and graphite. Brass electrode gives better surface finishing which is 15 ?m and graphite electrodes give the better electrode wear rate which is 0.53 among two electrodes. Key words: Electrical Discharge Machining, Surface Roughness, Material Removal Rate, Electrode Wear Ratio.

The mastery of writing skill is a crucial for ESL/EFL students. Scholars in the field of language teaching and learning have suggested so many strategies and methods to improve writing compositing. One of these methods is journal writing. However, whether the students actually realize that journal writing may improve a special kind of writing has not been explored. Therefore, the present study was conducted to investigate the effect of applying journal writing on the descriptive, reflective, and critical ability of EFL learners. The study included 80 male and female EFL learners of Hermes institute at the advanced level of language proficiency who were selected, and randomly assigned to experimental and control group. In the course of 10 sessions, the experimental group took the pretest and post test by which the teacher feedback and during which the treatment rubric were introduced. In control group, besides the pretest and posttest, they were provided with traditional writing with no treatment. Descriptive statistics and a paired sample t-test were utilized to analyze the data demonstrated that the two groups were significantly different regarding their writing ability. In order to compare the posttest of the three experimental groups while taking into account their initial differences on pretest (i.e. covariate) ANCOVA was administered. It was concluded that descriptive and reflective models of writing can lead to higher improvement in writing. In other words, the results of this study revealed that descriptive and reflective journal writing have positive effects on the learners’ writing achievements and provided opportunity for teachers to modify and revise their teaching performances in terms of allocating much time on the content of the learners’ writings to achieve the qualified teaching and learning.

Grievances or conflicts are part of industrial/ corporate scenario. In the working lives, employees occasionally have reasons to be uncomfortable, disappointed or aggrieved either about certain managerial decisions and practices or service conditions. The question then is whether this particular symptom or feeling is given any attention or is ignored altogether. What are the pros and cons of each of the approaches? The conflicts or disappointments cannot be eliminated but their expressions will contribute towards their reduction. Such expressions lead to adjustments and further improved organizational effectiveness. To a large extent, the approach to the problem will be governed by several variables such as the style of management, size of the enterprise, level of education of the workforce, technology of the plant and the extent of unionization of the work force.

The formalized theory of the identification of genotypes by their phenotypes in modern breeding technologies is offer. It erect on the mathematical model of the interaction "genotype-environment".

The paper explores the herding relationship between spot market and futures market by using two different herding measurements. Heavily traded constituents stocks of Taiwan electronic sector index and finance sector index are used to test the existence of herding. We also examine whether herding behavior has asymmetric reactions for up (bull) markets and down (bear) markets. Daily and 15-minute returns data covering Taiwan spot market and Taiwan futures market are analyzed. The results partly support the information cascade theory and rational asset pricing theory. Investors do herd temporarily but also trade rationally in a long period. Furthermore, daily and 15-minute data demonstrate the investors’ tendency toward herding is higher during market downstream.

In Wireless Sensor Networks, cluster head is the key technology where nodes or motes the information transmit it to the base station. The energy consumption in a wireless sensor network can be reduced by allowing only some nodes to communicate with the base station. One way to support efficient communication between sensors is to organize the network into multiple groups, called clusters, with each cluster electing one node as the head of cluster. To support scalability, nodes are often grouped mostly non-overlapping clusters. This paper proposes a new design of an efficient clustering in wireless sensor head which is based on two level clustering. In two levels clustering approach instead of sensor nodes sends the data to cluster heads directly, each node sends data to their cluster head and then sends data to the base station.

Retrocaval ureter is a rare disease found most often in young adult males, the usual clinical manifestation is right lumbar pain due to obstruction of the upper urinary tract. The diagnosis is based on CT and the treatment is mainly laparoscopic as our observation shows.

In this work, FT-IR and FT-Raman spectra are recorded on the solid phase of methyl 2-chloronicotinate in the regions 4000–400 cm-1 and 3500–100 cm-1 respectively. The geometrical parameters, vibrational assignments, HOMO–LUMO energies and NBO calculations are obtained for the monomer and dimer of methyl 2-chloronicotinate from DFT (B3LYP) with 6-311++G (d, p) basis set calculations. Second order perturbation energies and electron density (ED) transfer from filled lone pairs of Lewis base to unfilled Lewis acid sites of methyl 2-chloronicotinate are discussed on the basis of NBO analysis. give the evidence for the formation of dimer entities in the title molecule. The theoretically calculated harmonic frequencies are scaled by common scale factor. The observed and the calculated frequencies are found to be in good agreement. The thermodynamic functions were obtained for the range of temperature 100–1000 K. The polarizability, first hyperpolarizability, anisotropy polarizability invariant has been computed using quantum chemical calculations. The chemical parameters were calculated from the HOMO and LUMO values. The NMR chemical shielding anisotropy (CSA) parameters were also computed for the title molecule.

Improving distribution systems performance has become a significant issue as a result of large increase in electrical power consumption during recent years. The system operators aim to enhance efficiency of the distribution system in both dynamic and static modes. While DFACTS has commonly been employed to promote distribution systems capability in dynamic mode, this paper proposes a new static technique based on using interline dynamic voltage restorer (IDVR) to make a virtual smooth load duration curve for the adjacent loads having different load curves. Such a technique can be used for peak shaving and help the operator postpones the system expansion necessity. Furthermore, as a result of virtual smoothing load duration curve, voltage security margin and system reliability which are two important topics in static performance of the distribution systems will be enhanced. The simulation results demonstrate the suitability of the proposed technique.

In this analysis, the viscous dissipation and heat source effects on free convective boundary layer slip flow due to induced magnetic field is studied. The governing partial differential equations are converted into ordinary differential equations by using the similarity transformations. In which the coupled non linear differential equations are solved by using regular perturbation technique. The effects of various parameters on the velocity, temperature, induced magnetic field and also the local skin friction, the rate of heat transfer are presented through graphically and tabulated values in detailed.