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71.
One of the imperatives for improving the quality-of-service (QoS) of high-speed networks of next generation is to reduce congestion. Congestion occurs when the resource demand exceeds the capacity of the network. The purpose of this paper is to analyze the performance of Robust Adaptive Congestion Control algorithm for available bit rate traffic in asynchronous transfer mode networks and suggest improvements of the algorithm for better performance and fairness. The results of simulation presented here corroborates the fact that the improved algorithm reduces settling time and cell loss ratio and thus maximizes utilization of the network. 相似文献
72.
An analytical solution is developed to predict spatio-temporal variation of the water table in a 2-D aquifer system which is receiving transient recharge from an overlying basin of rectangular shape. The transient recharge function is approximated by a number of line segments. Application of the solution is demonstrated with the help of an example problem. 相似文献
73.
74.
A prior knowledge of the water table fluctuations, in response to the proposed recharge scheme, is essential to achieve the preset objectives of ground water resources management. In this paper an analytical solution of the linearised Boussinesq's equation is presented to predict the spatio-temporal variation of the water table in an aquifer system in response to time-varying recharge applied through a rectangular basin. The recharge function is approximated by introducing a number of line segments depending on its nature of variation. The solution is obtained by using finite Fourier sine transform and its application is demonstrated for a case of periodically applied recharge. 相似文献
75.
Warranty data are a rich source of information for feedback on product reliability. However, two-dimensional automobile warranties that include both time and mileage limits, pose two interesting and challenging problems in reliability studies. First, warranty data are restricted only to the reported failures within warranty coverage and such incompleteness can lead to inaccurate estimates of field failure rate or hazard rate. Second, factors such as inexact time/mileage data and vague reported failures in a warranty claim make warranty data unclean that can suppress inherent failure pattern. In this paper we discuss two parameter estimation methods that address the incompleteness issue. We use a simulation-based experiment to study these estimation methods when departure from normality and varying amount of truncation exists. Using a life cycle model of the vehicle, we also highlight and explore issues that lead to warranty data not being very clean. We then propose a five-step methodology to arrive at meaningful component level empirical hazard plots from incomplete and unclean warranty data. 相似文献
76.
77.
Cyclins are essential proteins in cell cycle control, and their deranged expression has been reported to be associated with malignant transformation. Involvement of cyclins in the development of endometrioid carcinomas of the endometrium was studied immunohistochemically using antibodies against both cyclin A and tumor suppressor gene product p53, and their expression was compared with that of Ki-67 antigen. Sixty-two cases of endometrial endometrioid carcinoma and 20 cases of normal endometrium (10 proliferative and 10 secretory phase) were examined. Of the 62 endometrioid carcinomas, atrophic endometrium and hyperplasia were found adjacent to the cancers in 30 and 19 cases respectively. Cyclin A was expressed in < 1% of the glandular cells of normal endometrium in the proliferative phase and in hyperplasia, but was negligible in normal secretory phase and atrophic endometrium. p53 was almost always negative in normal endometrium and hyperplasia. Of the 62 endometrioid carcinomas, 12 tumors (19.4%) overexpressed cyclin A and 21 tumors (33.8%) overexpressed p53 (positive cells > 1%). Cyclin A and p53 were more frequently expressed in poorly differentiated tumors than in well differentiated tumors (cyclin A, p = 0.002; p53, p = 0.016). In addition, cyclin A-positive cells were topographically related to those cells positive for p53 as well as Ki-67. In conclusion, the abnormal expression of cyclin A and p53 is associated with high-grade endometrial endometrioid carcinomas. 相似文献
78.
Rai A. WhaleyConnell A. Khanna R. 《Hemodialysis international. International Symposium on Home Hemodialysis》2005,9(1):90-91
An increased frequency of the Milk‐Alkali syndrome in the last several years has been noticed related to increasing use of calcium carbonate as a phosphate binder in CKD patients, as an antacid or as calcium supplementation. We present a case of severe hypercalcemia secondary to Milk‐Alkali syndrome that precipitated acute renal failure requiring urgent hemodialysis. A 59-year‐old male with history of hypertension, diabetes mellitus, and acid reflux presented to the ER with confusion, lethargy, nausea, vomiting, and diarrhea. His family relayed a history of recent indigestion and relief with Tums. He was taking several tablets at short intervals to self‐treat the indigestion. At the time of presentation, patient was confused and noted to be dehydrated. Lab findings were significant for elevated BUN/Cr‐ 121 mg/dl/11.1 mg/dl (baseline Cr 1.1 mg/dl few months ago), bicarbonate 38 mg/dl, calcium 16.7 mg/dl, ionized Ca of 1.76 mmol/L, iPTH 10 pg/ml, PTHrP 0.7 pg/ml. Medical management with intravenous fluids and furosemide showed no improvement in renal failure, or calcium level. Patient was then started on hemodialysis with 2.0 mmol/L calcium in the dialysate the next day. There was gradual improvement in patient's mental status, calcium values, and renal failure over the ensuing 2 weeks.
Discussion and Conclusions: The diagnosis of Milk‐Alkali syndrome is made on the basis of history. Metabolic abnormalities involved in this syndrome are hypercalcemia with low to normal PTH and Vit. D levels, renal failure, and metabolic alkalosis. Failed medical management required acute dialysis in this patient. Acute hemodialysis in such a case could be life saving. Due to increasing use of calcium carbonate for dyspepsia and osteoporosis, patients should be made aware of these severe, potentially life-threatening adverse effects. 相似文献
Discussion and Conclusions: The diagnosis of Milk‐Alkali syndrome is made on the basis of history. Metabolic abnormalities involved in this syndrome are hypercalcemia with low to normal PTH and Vit. D levels, renal failure, and metabolic alkalosis. Failed medical management required acute dialysis in this patient. Acute hemodialysis in such a case could be life saving. Due to increasing use of calcium carbonate for dyspepsia and osteoporosis, patients should be made aware of these severe, potentially life-threatening adverse effects. 相似文献
79.
Rajesh Kumar Gayatri Sahu Shailendra K. Saxena Hari M. Rai Pankaj R. Sagdeo 《SILICON》2014,6(2):117-121
A qualitative evolution of an asymmetric Raman line-shape function from a Lorentzian line-shape is discussed here for application in low dimensional semiconductors. The step-by-step evolution reported here is based on the phonon confinement model which is successfully used in literature to explain the asymmetric Raman line-shape from semiconductor nanostructures. Physical significance of different terms in the theoretical asymmetric Raman line-shape has been explained here. Better understanding of theoretical reasoning behind each term allows one to use the theoretical Raman line-shape without going into the details of theory from first principle. This will enable one to empirically derive a theoretical Raman line-shape function for any material if information about its phonon dispersion relation, size dependence, etc., is known. 相似文献
80.
Complexes of salicylic acid (Sal) and 1,10-phenanthroline (Phen) were synthesized coordinated with terbium ion (Tb3+) in crystalline phases. The structural characterizations of the lanthanide complex were made using FT-IR, NMR (1H and 13C) and XRD techniques. These measurements confirm the formation of Tb(Sal)3Phen complex structure. The thermal aspects of the complex were examined using DTA and TGA techniques. An enhancement in luminescence intensity of Tb3+ ion bands were observed in Tb(Sal)3Phen complex as compared to TbCl3 crystals on 355 nm laser excitation. Enhancement is reported due to the efficient energy transfer process from Sal to Tb3+ ions. This is also confirmed by the time resolved photoluminescence spectroscopy with increase in lifetime of Tb3+ ions due to encapsulation in Sal/Phen network. Our system in itself can be a deserving candidate for luminescent solar collector material when coupled with solar cells. 相似文献