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61.
A mixture of 125I labeled meglumine diatrizoate and 131I labeled human serum albumin was injected into the lower abdominal aorta of 30 anesthetized, laparotomized male rats. Measurements of the activities in cardiac blood and in different tissues of the hindlimbs and tests were perfomed at six time intervals ranging from 5 seconds to 2 minutes after injection, the determine early uptake and distribution volumes of diatrizoate. Concentrations and distribution volumes were initially much greater than values obtained after intravenous injection, but these differences had considerably decreased or disappeared by 2 minutes. 相似文献
62.
This paper develops a concept of Panoramic Appearance Map (PAM) for performing person reidentification in a multi-camera setup.
Each person is tracked in multiple cameras and the position on the floor plan is determined using triangulation. Using the
geometry of the cameras and the person location, a panoramic map centered at the person’s location is created with the horizontal
axis representing the azimuth angle and vertical axis representing the height. Each pixel in the map image gets color information
from the cameras which can observe it. The maps between different tracks are compared using a distance measure based on weighted
SSD in order to select the best match. Temporalintegration by registering multiple maps over the tracking period improves
the matching performance. Experimental results of matching persons between two camera sets show the effectiveness of the approach.
This work has been sponsored by the Technical Support Working Group (TSWG) of US Department of Defence (DoD). 相似文献
63.
Michael Grottke Kishor S. Trivedi 《Computer》2007,40(2):107-109
Even if software developers don't fully understand the faults or know their location in the code, software rejuvenation can help avoid failures in the presence of aging-related bugs. This is good news because reproducing and isolating an aging-related bug can be quite involved, similar to other Mandelbugs. Moreover, monitoring for signs of software aging can even help detect software faults that were missed during the development and testing phases. If, on the other hand, a developer can detect a specific aging-related bug in the code, fixing it and distributing a software update might be worthwhile. In the case of the Patriot missile-defense system, a modified version of the software was indeed prepared and deployed to users. It arrived at Dhahran on 26 February 1991- a day after the fatal incident 相似文献
64.
A multidisciplinary research effort at UCSD focuses on the design, development, and evaluation of novel computational frameworks for vehicle-based safety systems. The dynamic active display presents visual alerts to the driver based on the surrounding environment, vehicle dynamics, and driver's state as well as a driver-intent analysis and situational awareness system. 相似文献
65.
H. Walker Shan Liu J. H. Lee R. Trivedi 《Metallurgical and Materials Transactions A》2007,38(7):1417-1425
Critical experimental studies have been carried out to examine the stability of eutectic morphology in three-dimensional (3-D)
samples under diffusive growth conditions. By directionally solidifying capillary samples of the well-characterized Al-Cu
eutectic alloy, it is shown that the observed minimum spacing agrees with the value predicted by the Jackson and Hunt (JH)
model, but the range of stable spacing is reduced significantly in three dimensions. The ratio of the maximum to minimum eutectic
spacing in three dimensions is found to be only 1.2 compared to the predicted value of 2.0 in two dimensions. The narrow range
of stable spacing is shown to be due to the instabilities in the third dimension that forms when the local spacing becomes
larger than some critical spacing value, which corresponds to the maximum stable spacing. A new mechanism of lamellar creation
in the third dimension is observed in which lamella with a local spacing larger than the critical value becomes unstable and
forms a sidewise perturbation that becomes enlarged at the leading front and then propagates parallel to the lamella to create
a new lamella. Alternately, an array of sidewise perturbations form, which then coalesce at their leading fronts and then
become detached from the parent lamella to form a new lamella.
This article is based on a presentation made in the symposium entitled “Solidification Modeling and Microstructure Formation:
In Honor of Prof. John Hunt,” which occurred March 13–15, 2006, during the TMS Spring Meeting in San Antonio, Texas, under
the auspices of the TMS Materials Processing and Manufacturing Division, Solidification Committee. 相似文献
66.
Accurate segmentation of foreground objects in video scenes is critical for assuring reliable performance of vision systems
for object tracking and situational awareness in outdoor scenes. Most existing techniques for background modeling and shadow
suppression require that a number of parameters be “hand-tuned” based on environmental conditions. This paper presents two
contributions to overcome such limitations. First, we develop and demonstrate a satellite imagery based approach for selecting
appropriate background and shadow models. It is shown that the illumination conditions (i.e. cloud cover) of a scene can be
reliably inferred from visible satellite images in the local region of the camera. The second contribution presented in the
paper is introduction and evaluation of a Hybrid Cone-Cylinder Codebook (HC3) model which combines an adaptive efficient background
model with HSV-color space shadow suppression into a single coherent framework. The structure of the HC3 model allows for
seamless fusion of the satellite data. We are thereby able to exploit the fact that, for example, shadows are more pronounced
on sunny days than cloudy days, allowing for more sensitive detection. The paper presents a set of experiments using day long
sequences of videos from an operational surveillance system testbed. Results of these experimental analyses quantitatively
illustrate the benefits of using satellite imagery to inform and adaptively adjust background and shadow modeling. 相似文献
67.
Dyer JA Trivedi P Sanders SJ Scrivner NC Sparks DL 《Environmental science & technology》2003,37(5):923-930
Few studies have demonstrated the practical application of surface complexation models, calibrated with fundamental macroscopic and spectroscopic metal sorption data, in helping to solve industrial trace metal emissions problems. In this work, multistage ferrihydrite sorption systems are evaluated for their effectiveness in reducing single-solute lead(II) [Pb(II)] concentrations in contaminated water streams to very low levels. Experimental data and modeling results indicate that a multistage sorption system can significantly reduce Pb(II) effluent concentrations for the same total amount of sorbent or, alternatively, dramatically lower total sorbent consumption for the same effluent Pb(II) concentration. Model predictions were generated using a steady-state, multistage, equilibrium adsorber model that was specifically developed for and integrated into 0LI Systems' Environmental Simulation Program. The modified triple-layer model was used to simulate Pb(II) surface-liquid equilibria within the adsorber model. Engineering screening evaluations indicate that a 2-3-stage sorption process can provide significant economic savings when compared to a 1-stage process operating with the same target effluent Pb(II) concentration. Additional equilibrium stages beyond 2 or 3 provide diminishing economic returns. The major economic driver for multiple contacting stages is reduced capital investment and operating costs for sludge handling, dewatering, and disposal. 相似文献
68.
PURPOSE: To assess long-term survival following cladribine salvage treatment for previously treated patients with chronic lymphocytic leukemia. PATIENTS AND METHODS: Fifty-two patients aged 39-84 years with previously treated CLL received cladribine 0.12 mg/kg/day in 2-hour infusions for 5 days in monthly courses. Two-thirds were refractory to previous therapy, and 8 had prior fludarabine. RESULTS: Sixteen (31%) patients achieved complete response (CR) and 14 (27%) partial remission (PR) according to consensus criteria. Response correlated with clinical stage, number of previous treatment regimes, blood lymphocyte count, and lymphocyte halflife following the first cladribine course. Toxicity included pneumonia (n = 9), herpes zoster (n = 7), and septicemia (n = 2). Four patients in CR underwent high-dose chemotherapy with autologous blood stem cell support, and 2 remain in CR 48 and 60 months from start of cladribine, and 2 had relapse at 42 and 48 months, respectively. Median progression-free survival (Kaplan-Meier analysis) for CR patients was 23 months from start of cladribine treatment, and for PR patients 16 months. The projected overall survival was 80% at 3 years for CR patients, and the median survival 28 months for PR patients and 4 months for non-responding patients. CONCLUSIONS: Our previous finding of durable CRs from cladribine in advanced CLL is thus confirmed in a larger patient material, and follow-up indicate that long-term survival may be achieved. 相似文献
69.
70.