A methodology for the performance evaluation of data querystrategies in universal mobile telecommunication systems (UMTS)

The anticipated emergence of third-generation mobile systems, referred to as universal mobile telecommunication systems (UMTS), raises the problem of reconsidering the design of the databases destined to contain the user information. In particular, it is expected that the key concepts of the new database architectures will be high distribution and fast updating of information. So far, the problem of determining the most appropriate distributed database (DDB) architectures for third-generation mobile systems has not been widely dealt with in literature. This paper presents a methodology for evaluating hierarchical DDB architectures by means of an analytical model of the data querying operation. This methodology allows for structural alternatives, differing on account of the number of levels and branches in the hierarchy, to be evaluated in terms of query loads and mean response times, according to a given user mobility characterization and a given search protocol operation. By way of illustration, the paper discusses a case study, concerning a query operation arising from a location updating procedure and applied to a hierarchical tree-like DDB in which some structural alternatives are considered     

Evaluation of ecological effectiveness for dust-separation systems

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 5, pp. 30–31, May, 1992.     

Synthesis and release of ATP by soluble mitochondrial F1 in complex with its inhibitor protein during dimethylsulfoxide-water transitions

Soluble mitochondrial F1 and F1 in complex with the natural ATPase inhibitor protein (F1-IP) catalyze the spontaneous synthesis of [gamma-32P]ATP from medium [32P]phosphate and enzyme-bound ADP when incubated in media with dimethylsulfoxide (Me2SO); under these conditions, the synthesized [gamma-32P]ATP is not released into the media, it remains tightly bound to the enzymes [Gómez-Puyou, A., Tuena de Gómez-Puyou, M. & de Meis, L. (1986) Eur. J. Biochem. 159, 133-140]. Some of the characteristics of the synthesized [gamma-32P]ATP were studied in F1 and F1-IP (ATPase activities of 70 and 1-3 micromol x min(-1) x mg(-1), respectively). In Me2SO media, gamma-phosphate of synthesized ATP in F1 or F1-IP exchanges with medium phosphate. From the rates of the exchange reaction, the half-times for hydrolysis of the synthesized ATP in F1 and F1-IP were calculated: 45 min and 58 min for F1 and F1-IP, respectively. The course that synthesized [gamma-32P]ATP follows after dilution of the Me2SO synthetic mixture with aqueous buffer was determined. After dilution, the half-life of synthesized ATP in F1 was less than 1 min. In F1-IP, ATP was also hydrolyzed, but at significantly lower rates. In F1-IP, dilution also produced release of the synthesized [gamma-32P]ATP. This was assayed by the accessibility of [gamma-32P]ATP to hexokinase. About 25% of [gamma-32P]ATP synthesized in F1-IP, but not in F1, was released into the media after dilution with aqueous buffer that contained 20 mM phosphate. Release of tightly bound ATP required the binding energy of phosphate and solvation of F1-IP, however, the particular kinetics of F1-IP were also central for medium ATP synthesis in the absence of electrochemical H+ gradients.     

Oblique flow impinging on a wall with suction or blowing

Summary The oblique flow of a viscous fluid impinging on a flat wall with suction or blowing is studied. It is found that when suction is applied the fluid penetrates the wall while blowing causes the shifting of the stagnation point. It is also found that this shifting depends upon the magnitude of the blowing.     

Two bit correlation-an adaptive time delay estimation

Time delay estimation is a very important operation in ultrasound time-domain flow mapping and correction of phase aberration of an array transducer. As the interest increases in the application of one and a half-dimensional (1.5-D) and two-dimensional (2-D) array transducers to improving image quality and three-dimensional (3-D) imaging, the need of simple, fast, and sufficiently accurate algorithms for real-time time delay estimation becomes exceedingly crucial. In this paper, we present an adaptive time-delay estimation algorithm which minimizes the problem of noise sensitivity associated with the one bit correlation while retaining simplicity in implementation. This algorithm converts each sample datum into a two bit representation including the sign of the sample and an adaptively selected threshold. A bit pattern correlation operation is applied to find the time delay between two engaged signals. By using the criterion of misregistration as an indicator, we are able to show that the proposed algorithm is better than one bit correlation in susceptibility to noise level. Analytical results show that the improvement in reducing misregistration of the two bit correlation over its counterpart is consistent over a wide range of noise level. This is achieved by an adaptive adjustment of the threshold to accommodate signal corruption due to noise. The analytical results are corroborated by results from simulating the blood as a random distribution of red blood cells. Finally, we also present a memory-based architecture to implement the two bit correlation algorithm whose computation time does not depend upon the time delay of the signals to be correlated     

Numerical investigation of the convection of heat-emitting liquid reactor materials taking stratification into account

Conclusions The calculations for the different levels of volume heat release showed that the integral heat fluxes at the lateral and top surfaces are virtually independent of the scenario of convective flow. However, the maximum of the heat flux on the lateral surface in the homogeneous case is 1.5–1.6 times higher than the maximum heat flux in the stratified case. This could result in larger mechanical loads on the reactor vessel and therefore more stringent requirements on the cooling of the outer surface of the reactor vessel. Institute of Fast Reactors, Russian Academy of Sciences. Translated from Atomnaya énergiya, Vol. 76, No. 5, pp. 406–411, May, 1994.     

Topical use of aprotinin in open heart operations

Among various pharmacological agents used to reduce bleeding after open-heart operations, high-dose aprotinin therapy seems most promising. However, its long-term effects are still obscure; there is almost always possibility of bypass graft occlusions produced by the hypercoagulable state induced by aprotinin in coronary bypass operations. Topical application of aprotinin into the pericardial cavity could prevent the adverse effects. Fifty patients were prospectively studied to evaluate the effects of topical aprotinin. One million KIU of aprotinin was poured into the pericardial cavity before closure of the sternotomy in group 1 (n = 25). Patients in group 2 (n = 25) served as controls. Total postoperative bleeding was significantly reduced in group 1 when compared with that of group 2 (722.7 +/- 230.8 versus 1,282.6 +/- 225.7 mL; p < 0.01). The use of banked donor blood products was significantly less in group 1 than in group 2 (0.33 +/- 0.67 versus 1.36 +/- 0.86 units; p < 0.01). These results show that topical use of aprotinin reduces post-operative blood loss and need for transfusion. It seems promising and warrants further studies to be done.