Abstract: By placing the whirling element in the nozzle body, swirling abrasive jet has been produced. The speed function of spiral groove and swirling contraction segment in inner of nozzle are analyzed. And the formulas of speed function are obtained. It is seen that movement of fluid in the spiral groove is regarded as spiral one-dimension axial symmetry, movement of fluid in the swirling contraction as spiral two-dimension axial symmetry. The swirling abrasive jet system has been established. The production method and the drilling test system of the swirling abrasive jet are introduced. The drilling mechanism of the swirling abrasive jet is analyzed. Through experiment, the effects of the whirling element structure and the jet parameters on drilling performance are studied. The results indicated that in the case of nozzle non-rotation, under the working pressure of 10 MPa, swirling abrasive jet can drill a deep hole on coal block of which Polodyakonov coefficient f is about 4, and that the diameter of the hole is 20~30 times the size of the nozzle exit diameter. So the swirling abrasive jet has a good drilling performance.
Abstract: In this study implementing Supply Chain Management (SCM) among Malaysian automotive industries are considered to recognize what kind of problems suffered by those organizations when SCM was applied. Survey questionnaire was used to gather the data needed. The questionnaire was distributed to 300 Malaysian’s automotive organizations and a total of 62 replies were usable. The survey reveals that companies suffer from the lack of information as major difficulty during implementing SCM. The findings of this research would give invaluable information to all researchers and practitioners in the field of SCM.
Abstract: Electromigration(EM) failure can be occurred in the via because of the high aspect ratio of Via and the high stress in the via. The theoretical and experimental study is developed in detail. The different via structures are designed and the simulation and accelerate test is operated. The result shows the current density and electric field in the via is decreased apparently and reliability is improved by use the structures, so it is considered of the practical means for improving the copper via interconnect reliability. Finally, two optimized via structures are advanced based on the result of experiments and simulations. The two structures are instructive for the design and manufacture.
Abstract: It’s difficult to measure bottom pressure in the fractured-vuggy reservoir, and measuring cost is usually high; In this paper, using the modified Beggs-Brill method, the variety of wellbore pressure has been calculated and analyzed. Results show that the variety of wellhead pressure is consistent with that of bottom pressure, and the variety of wellhead pressure is greater than that of bottom pressure. Thereby a simple method of predicting bottom pressure through wellhead pressure is established. Through example calculation, it’s confirmed that this method has a certain reliability and practicability.
Abstract: Conflicting results in the effect of OC on Atterberg limits need to a clarification with more studies. The observation that why PL increases in the higher rate than LL would be interesting issue to more investigation. Thus, this paper is focused on the index properties of OS (Site A) and SOS (Site B). It was found that removing OC in Site A affect particle size distribution by a dispersion phenomena while no effect was observed in Site B. Presence of average 13.6 % OC in site A leaded to increase in liquid and plastic limits for 6.1% and 26.9 %, respectively.