The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
William C. Little - One of the best experts on this subject based on the ideXlab platform.
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External Pressure of undisturbed left ventricle.
American Journal of Physiology-heart and Circulatory Physiology, 1990Co-Authors: Robert J. Applegate, William P. Santamore, H. S. Klopfenstein, William C. LittleAbstract:We evaluated the contribution of the thorax and the undisturbed pericardium to the External Pressure of the euvolemic left ventricle in thirteen anesthetized dogs. Left ventricular (LV) end-diastol...
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External Pressure of undisturbed left ventricle.
The American journal of physiology, 1990Co-Authors: Robert J. Applegate, William P. Santamore, H. S. Klopfenstein, William C. LittleAbstract:We evaluated the contribution of the thorax and the undisturbed pericardium to the External Pressure of the euvolemic left ventricle in thirteen anesthetized dogs. Left ventricular (LV) end-diastolic Pressure (EDP) in the euvolemic state was 7 +/- 2 mmHg initially and increased to 10 +/- 2 mmHg after the chest and pericardium were opened. LV end-diastolic volume (conductance catheter) was 43 +/- 20 ml initially and did not change after the chest or the pericardium was opened. Intrathoracic (PIT) and pericardial (PPER) Pressures were calculated as the difference in LV chamber Pressure before and after opening these spaces. Thus for the LV, PIT was -3 +/- 1 mmHg, and PPER was 0 +/- 2 mmHg. Isovolumic relaxation, early diastolic filling, and total diastolic filling were not significantly altered after the chest or pericardium was opened. Thus under euvolemic conditions in this model pericardial Pressure is negligible, and the External Pressure of the undisturbed left ventricle is negative and equal to intrathoracic Pressure.
Wenjun Huang - One of the best experts on this subject based on the ideXlab platform.
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a theoretical study of the critical External Pressure for casing collapse
Journal of Natural Gas Science and Engineering, 2015Co-Authors: Wenjun HuangAbstract:Abstract A new theoretical casing collapse model is proposed on the basis of a refined reduced modulus calculation method. The reduced modulus of considers the co-existence of the elastic and plastic regions on the casing cross section. The collapse Pressure for an ideal circular casing is expressed as a weighted harmonic sum of the critical elastic Pressure and casing yielding Pressure. Three kinds of casing imperfections including the wall thickness variation, ovality and non-uniform External Pressure on casing collapse are further considered to amend the ideal casing collapse model. The equivalent wall thickness due to wall thickness variation is introduced, and the critical elastic Pressure and yielding Pressure under the effects of initial ovality and non-uniform External Pressure are obtained. On this basis, the collapse Pressure for an oval casing with thickness variation under non-uniform External Pressure is obtained with superposition principle. The effects of axial force, bending moment and torque on collapse Pressure are included with the reduced yielding point. All the above factors are integrated into a unified casing collapse model. At last, the comparison between the new model and API specification is further discussed. The results indicate that the new model gives a more sophisticated description of casing collapse problem. Introducing the casing imperfections improves the consistency between the theoretical and experimental results at the transition between elastic and plastic ranges. The non-uniform External Pressure plays the most important role in the casing collapse problem. The existence of non-uniform External Pressure, axial force, bending moment and torque also reduces the critical casing collapse Pressure a lot.
Vinh T Nguyen - One of the best experts on this subject based on the ideXlab platform.
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buckling under the External Pressure of cylindrical shells with variable thickness
International Journal of Solids and Structures, 2009Co-Authors: Hien Luong T Nguyen, Isaac Elishakoff, Vinh T NguyenAbstract:Abstract This study focuses on the buckling of cylindrical shells with small thickness variations under External Pressure. Asymptotic formulas in terms of the thickness non-uniformity parameter are derived by the combined perturbation and Bubnov–Galerkin methods. In addition to the analytic investigation based on the thin shell theory, a numerical analysis is also performed. Results from these formulas are discussed and compared with those obtained by other authors.
Flora He - One of the best experts on this subject based on the ideXlab platform.
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studies of tin whisker growth under high External Pressure
International Microsystems Packaging Assembly and Circuits Technology Conference, 2017Co-Authors: Flora He, Alex Fung, Crystal P L Li, Dennis Chit Yiu ChanAbstract:In this study, a series of factors that may affect whisker growth on electroplated tin coatings under high External Pressure were studied by an indentation method, including storage time, coating thickness, loading and ball diameter. The indentation test results showed that longer storage time, thicker coating (< 3 μm), heavier loading and smaller inert ball could accelerate whisker growth. In addition, the insertion force, retention force and whisker behavior of compliant press-fit pins inserted into the same design of plated through holes with three different types of final finishes (Immersion tin, ENIG and OSP) were investigated.
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Studies of tin whisker growth under high External Pressure
2017 12th International Microsystems Packaging Assembly and Circuits Technology Conference (IMPACT), 2017Co-Authors: Flora He, Alex Fung, Crystal Li, Dennis ChanAbstract:In this study, a series of factors that may affect whisker growth on electroplated tin coatings under high External Pressure were studied by an indentation method, including storage time, coating thickness, loading and ball diameter. The indentation test results showed that longer storage time, thicker coating (
Robert J. Applegate - One of the best experts on this subject based on the ideXlab platform.
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External Pressure of undisturbed left ventricle.
American Journal of Physiology-heart and Circulatory Physiology, 1990Co-Authors: Robert J. Applegate, William P. Santamore, H. S. Klopfenstein, William C. LittleAbstract:We evaluated the contribution of the thorax and the undisturbed pericardium to the External Pressure of the euvolemic left ventricle in thirteen anesthetized dogs. Left ventricular (LV) end-diastol...
-
External Pressure of undisturbed left ventricle.
The American journal of physiology, 1990Co-Authors: Robert J. Applegate, William P. Santamore, H. S. Klopfenstein, William C. LittleAbstract:We evaluated the contribution of the thorax and the undisturbed pericardium to the External Pressure of the euvolemic left ventricle in thirteen anesthetized dogs. Left ventricular (LV) end-diastolic Pressure (EDP) in the euvolemic state was 7 +/- 2 mmHg initially and increased to 10 +/- 2 mmHg after the chest and pericardium were opened. LV end-diastolic volume (conductance catheter) was 43 +/- 20 ml initially and did not change after the chest or the pericardium was opened. Intrathoracic (PIT) and pericardial (PPER) Pressures were calculated as the difference in LV chamber Pressure before and after opening these spaces. Thus for the LV, PIT was -3 +/- 1 mmHg, and PPER was 0 +/- 2 mmHg. Isovolumic relaxation, early diastolic filling, and total diastolic filling were not significantly altered after the chest or pericardium was opened. Thus under euvolemic conditions in this model pericardial Pressure is negligible, and the External Pressure of the undisturbed left ventricle is negative and equal to intrathoracic Pressure.
