Spatial spectrum and energy efficiency of random cellular networks

It is a great challenge to evaluate the network performance of cellular mobile communication systems. In this paper, we propose new spatial spectrum and energy efficiency models for Poisson-Voronoi tessellation (PVT) random cellular networks. To evaluate the user access the network, a Markov chain based wireless channel access model is first proposed for PVT random cellular networks. On that basis, the outage probability and blocking probability of PVT random cellular networks are derived, which can be computed numerically. Furthermore, taking into account the call arrival rate, the path loss exponent and the base station (BS) density in random cellular networks, spatial spectrum and energy efficiency models are proposed and analyzed for PVT random cellular networks. Numerical simulations are conducted to evaluate the network spectrum and energy efficiency in PVT random cellular networks.Comment: appears in IEEE Transactions on Communications, April, 201

Is porto sinusoidal vascular disease to be actively searched in patients with portal vein thrombosis?

Porto sinusoidal vascular liver disease (PSVD) and portal vein thrombosis (PVT) are distinct vascular liver diseases characterized, respectively, by an intrahepatic and a prehepatic obstacle to the flow in the liver portal system. PVT may also occur as a complication of the natural history of PSVD, especially if a prothrombotic condition coexists. In other cases, it is associated to local and systemic pro-thrombotic conditions, even if its cause remains unknown in up to 25% despite an active search. In our opinion, the presence of PSVD should be suspected in patients with PVT especially in those with PVT "sine causa" and the active search of this condition should be included in their diagnostic work-out. However, sometimes the diagnosis of pre-existing PSVD is very hard. Biopsy cannot be fully discriminant as similar histological data have been described in both conditions. Liver stiffness may help as it has been shown to be higher in PSVD than in "pure" PVT, due to the presence of sclerosis in the portal venous radicles observable in PSVD patients. Nevertheless, comparing liver stiffness between PVT and PSVD has until now been restricted to very limited series of patients. In conclusion, even if it is still totally hypothetical, our point of view may have clinical consequences, especially when deciding to perform a liver biopsy in patients with a higher liver stiffness and suspending the anticoagulation in patients with PVT and no detectable prothrombotic factors

The GPS Assimilator: a Method for Upgrading Existing GPS User Equipment to Improve Accuracy, Robustness, and Resistance to Spoofing

Preprint of the 2010 ION GNSS Conference Portland, OR, September 21–24, 2010A conceptual method is presented for upgrading existing GPS user equipment, without requiring hardware or software modifications to the equipment, to improve the equipment’s position, velocity, and time (PVT) accuracy, to increase its PVT robustness in weak-signal or jammed environments, and to protect the equipment from counterfeit GPS signals (GPS spoofing). The method is embodied in a device called the GPS Assimilator that couples to the radio frequency (RF) input of an existing GPS receiver. The Assimilator extracts navigation and timing information from RF signals in its environment—including non-GNSS signals—and from direct baseband aiding provided, for example, by an inertial navigation system, a frequency reference, or the GPS user. The Assimilator optimally fuses the collective navigation and timing information to produce a PVT solution which, by virtue of the diverse navigation and timing sources on which it is based, is highly accurate and inherently robust to GPS signal obstruction and jamming. The Assimilator embeds the PVT solution in a synthesized set of GPS signals and injects these into the RF input of a target GPS receiver for which an accurate and robust PVT solution is desired. A prototype software-defined Assimilator device is presented with three example applications.Aerospace Engineerin

Modeling the correlations of crude oil properties based on sensitivity based linear learning method

This paper presented a new prediction model of pressure–volume–temperature (PVT) properties of crudeoil systems using sensitivity based linear learning method (SBLLM). PVT properties are very important in the reservoir engineering computations. The accurate determination of these properties, such as bubble-point pressure and oil formation volume factor, is important in the primary and subsequent development of an oil field. Earlier developed models are confronted with several limitations especially their instability and inconsistency during predictions. In this paper, a sensitivitybasedlinearlearningmethod (SBLLM) prediction model for PVT properties is presented using three distinct databases while comparing forecasting performance, using several kinds of evaluation criteria and quality measures, with neural network and the three common empirical correlations. In the formulation used, sensitivity analysis coupled with a linear training algorithm for each of the two layers is employed which ensures that the learning curve stabilizes soon and behaves homogenously throughout the entire process operation. In this way, the model will be able to adequately model PVT properties faster with high stability and consistency. Empirical results from simulations demonstrated that the proposed SBLLM model produced good generalization performance, with high stability and consistency, which are requisites of good prediction models in reservoir characterization and modeling

A high incidence of native portal vein thrombosis in veterans undergoing liver transplantation

The incidence of native portal vein thrombosis (PVT) in liver transplant recipients has been reported to range from 2.1 to 13.8%. We have identified an inordinately high incidence of PVT in a consecutive series of U.S. veterans receiving liver transplants. Between October 1989 and February 1994, 88 consecutive U.S. veterans received 99 orthotopic liver transplants under primary Tacrolimus (Prograf, formerly FK506) based immunosuppression. A number of clinical features were examined in an effort to identify risk factors for PVT and outcome was compared to patients without PVT. Native PVT was present in 23/88 (26%) patients. All of these patients were male U.S. veterans with a mean age of 47 years. When compared to the 65 patients without PVT, we found no significant difference with respect to underlying liver disease, age, Childs-Pugh score (mean = 12), UNOS status as defined prior to April 1995 (95% UNOS 3 or 4), previous abdominal surgery, or liver volume. Median blood loss for patients with PVT (21 units of packed red blood cells) was greater than for those without PVT (14 units, P = 0.04). Portal thrombectomy was performed in 11 patients, 11 patients required mesoportal jump grafts, and 1 patient had an interposition graft. Standard veno-venous bypass was used in 10 patients with single bypass utilized for the remainder. Actuarial patient survival for all patients at 1, 2, and 4 years was 88, 85, and 79%, respectively. There was no significant difference in patients with or without PVT. Patients with PVT had poorer graft survival than patients without PVT (86% vs 65%, 1 year; 81% vs 65%, 2 years; 81% vs 61%, 4 years; P = 0.03); however, this was not related to technical problems with the portal venous inflow. PVT occurred in 26% of U.S. veterans undergoing liver transplantation. These patients bad significantly higher operative blood loss and poorer graft survival. The high incidence of postnecrotic cirrhosis in a predominantly male group of patients with advanced disease, as is evident by the high mean Childs-Pugh score and UNOS status, perhaps accounts for our observations

UA1C12 559th AAA (AW) BN Broadside

Broadside of of logo of the 559th AAA (AW) BN with names of company members on one quarter of a sheet of paper. Transcription of notations and signatures: 571st AEA Medical Detachment (Independent) T/5 Chas. Gans (?) A - Battery 1st Sgt. Bing Miller S/Sgt. B.J. Martin S/Sgt. A. Hawkins S/Sgt. G. Swesnen S/Sgt B. Mallioux S/Sgt. M. Enevald S/Sgt. C. Watts Sgt. F. Glasser Sgt. E. Baseman Sgt. M. Krisan Pfc. Harry Shuler Pfc John Caggiano T/5 Ernest E. Black Pvt. Ed Nestel Cpl. Geo. O. Diamond Pvt. Donald D. Dreyr (?) Pvt. Patsy Lombardo B - Battery Cpl. Edw. J. Brennan Pvt. Clarence W. Parks Pvt. Sandy Orlando PFC Lewis Morris PFC Albert Koloman Pvt. Sigmund J. Bloom Pfc Cecil Arthur P.F.C. Antony Cornacchio P.F.C. Dorwood R. Bartlam Cpl. Geo. D. Egbert Pvt. Salvatore J. Borzillo PFC Mikey D. Magrone PFC Joseph A. Irrera Pfc Harry C. Wesler Pvt. Harold A. Mordt P.f.C. Jimmie N. Sha___ Pvt. Costello P.F.C. Albert Olson Pvt. Howard Hausenberger Pvt. Walter Steawart Pvt. Larry Cellucci Pvt. Bob Jones Pvt. Mac D. Williams PFC Harry Hermann Cpl. Chas. C. Eaton Pvt. Cellow Quock P.F.C. James R. Adams Cpl. Dan Ferraro Medics T/5 Ralph A. Lewis Cpl. S. Jakenborusky (?) (Yard Bird) Pvt. Donald R. Czoka 571st C Btry AAA AW BN.SP T/5 Eugene Richert Pvt. Bernard M. Piker T/5 Andrew McKenzie T/5 Frank Joe Wippel Cpl. Wm. Brackmann C - Battery P.F.C. Pat Piccirilli P.F.C. Thomas E. Beam P.FC Alvin E. Mann P.F.C. Joseph C. Jenkins Pvt M. Biconopard (?) P.F.C. Delbert R. Harris P.F.C. P.J. (Greek) Christofas P.F.C. J.E. (Perk) Perkinson Pvt. Thomas C. Angelone Cpl. Joseph T. Zabielska Jr. (?) Pfc. Ralph V. Caputo P.F.C. Van Riper Pvt. Charles Fisher Pvt. J.D. (Chick/Chuck) Cocahine (?) D - Battery Pvt. Don Forestien P.F.C. George P. Saxon Pvt. Jesse Collora Pvt. Bob Anton Cpl. Andy Geckle Pfc. Floyd J. Derkinson (?) Pvt. Charles Cummins CPl Alvin Bortz Pvt. M.W. Robinson Pvt. J.J. White Pvt. M. Kink Pvt. Frank Raniert Sgt. Jeff R. Donnelly Pvt. T. M. De Luca Pvt. Ralph Glazer Pfc. John Gruden Cpl. Howard Friedman P.f.C. Harold Hammond (?) PFC. Ed (Bagels) Puberlidfer (?) Cpl. John J. Nuzzo Pvt. Thomas J. Burns The 559th American Antiaircraft Artillery (AW) Battalion served in the European theater of World War II

Natural history of patients with non cirrhotic portal hypertension: Comparison with patients with compensated cirrhosis

Background. The knowledge of natural history of patients with portal hypertension (PH) not due to cirrhosis is less well known than that of cirrhotic patients. Aim. To describe the clinical presentation and the outcomes of 89 patients with non-cirrhotic PH (25 with non-cirrhotic portal hypertension, INCPH, and 64 with chronic portal vein thrombosis, PVT) in comparison with 77 patients with Child A cirrhosis. Methods. The patients were submitted to a standardized clinical, laboratory, ultrasonographic and endoscopic follow-up. Variceal progression, incidence of variceal bleeding, portal vein thrombosis, ascites and survival were recorded. Results. At presentation, the prevalence of varices, variceal bleeding and ascites was similar in the 3 groups. During follow-up, the rate of progression to varices at risk of bleeding (p<0.0001) and the incidence of first variceal bleeding (p=0.02) were significantly higher in non-cirrhotic then in cirrhotic patients. A PVT developed in 32% of INCPH patients and in 18% of cirrhotics (p=0.02). Conclusions. In the patients with non–cirrhotic PH variceal progression is more rapid and bleeding more frequent than in cirrhotics. Patients with INCPH are particularly prompt to develop PVT. This observational study suggests that the management of patients with non-cirrhotic PH should take into consideration the natural history of portal hypertension in these patients and cannot be simply derived by the observation of cirrhotic patients

Simulations of a Scintillator Compton Gamma Imager for Safety and Security

We are designing an all-scintillator Compton gamma imager for use in security investigations and remediation actions involving radioactive threat material. To satisfy requirements for a rugged and portable instrument, we have chosen solid scintillator for the active volumes of both the scatter and absorber detectors. Using the BEAMnrc/EGSnrc Monte Carlo simulation package, we have constructed models using four different materials for the scatter detector: LaBr_3, NaI, CaF_2 and PVT. We have compared the detector performances using angular resolution, efficiency, and image resolution. We find that while PVT provides worse performance than that of the detectors based entirely on inorganic scintillators, all of the materials investigated for the scatter detector have the potential to provide performance adequate for our purposes.Comment: Revised text and figures, Presented at SORMA West 2008, Published in IEEE Transactions on Nuclear Scienc