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141.
Rodrigues J Cancho VG de Castro M Balakrishnan N 《Statistical methods in medical research》2012,21(6):585-597
In this article, we propose a new Bayesian flexible cure rate survival model, which generalises the stochastic model of Klebanov et al. [Klebanov LB, Rachev ST and Yakovlev AY. A stochastic-model of radiation carcinogenesis - latent time distributions and their properties. Math Biosci 1993; 113: 51-75], and has much in common with the destructive model formulated by Rodrigues et al. [Rodrigues J, de Castro M, Balakrishnan N and Cancho VG. Destructive weighted Poisson cure rate models. Technical Report, Universidade Federal de S?o Carlos, S?o Carlos-SP. Brazil, 2009 (accepted in Lifetime Data Analysis)]. In our approach, the accumulated number of lesions or altered cells follows a compound weighted Poisson distribution. This model is more flexible than the promotion time cure model in terms of dispersion. Moreover, it possesses an interesting and realistic interpretation of the biological mechanism of the occurrence of the event of interest as it includes a destructive process of tumour cells after an initial treatment or the capacity of an individual exposed to irradiation to repair altered cells that results in cancer induction. In other words, what is recorded is only the damaged portion of the original number of altered cells not eliminated by the treatment or repaired by the repair system of an individual. Markov Chain Monte Carlo (MCMC) methods are then used to develop Bayesian inference for the proposed model. Also, some discussions on the model selection and an illustration with a cutaneous melanoma data set analysed by Rodrigues et al. [Rodrigues J, de Castro M, Balakrishnan N and Cancho VG. Destructive weighted Poisson cure rate models. Technical Report, Universidade Federal de S?o Carlos, S?o Carlos-SP. Brazil, 2009 (accepted in Lifetime Data Analysis)] are presented. 相似文献
142.
Aggressive scaling of silicon technology over the years has pushed CMOS devices to their fundamental limits. Pioneering works on carbon nanotube during the last decade possessing exceptional electrical properties have provided an intriguing solution for high performance integrated circuits. So far, at best, carbon nanotubes have been considered only for the channel, with metal electrodes being used for source/drain. Here, alternative schemes of 'All-Nanotube' transistor are presented where even the transistor components are derived from carbon nanotubes which hold the promise for smaller, faster, denser and more power efficient electronics. 相似文献
143.
Both AF Balakrishnan A Joseph B Marshall JD 《Environmental science & technology》2011,45(13):5629-5636
We measured outdoor fine particulate matter (PM(2.5)) concentrations in a low- and a nearby middle-income neighborhood in Bangalore, India. Each neighborhood included sampling locations near and not near a major road. One-minute average concentrations were recorded for 168 days during September 2008 to May 2009 using a gravimetric-corrected nephelometer. We also measured wind speed and direction, and PM(2.5) concentration as a function of distance from road. Average concentrations are 21-46% higher in the low- than in the middle-income neighborhood, and exhibit differing spatiotemporal patterns. For example, in the middle-income neighborhood, median concentrations are higher near-road than not near-road (56 versus 50 μg m(-3)); in the low-income neighborhood, the reverse holds (68 μg m(-3) near-road, 74 μg m(-3) not near-road), likely because of within-neighborhood residential emissions (e.g., cooking; trash combustion). A moving-average subtraction method used to infer local- versus urban-scale emissions confirms that local emissions are greater in the low-income neighborhood than in the middle-income neighborhood; however, relative contributions from local sources vary by time-of-day. Real-time relative humidity correction factors are important for accurately interpreting real-time nephelometer data. 相似文献
144.
145.
A. N. Papanicolaou P. Diplas C. L. Dancey M. Balakrishnan 《Canadian Metallurgical Quarterly》2001,127(3):211-218
In this study, the characteristics of near-bed turbulence were experimentally investigated for three distinct roughness regimes, namely (1) isolated; (2) wake interference; and (3) skimming. Spherical particles of the same size and density were placed upon a rough sediment bed to simulate the three regimes. Experimental runs for the aforementioned regimes were performed in a tilting water-recirculating flume. Flow measurements atop the spherical particles were performed by means of a 3D laser Doppler velocimeter. The aim of the tests was to provide further evidence that the structure of turbulence is affected throughout the boundary layer by the presence of roughness geometry. The measurements reported here include velocity profiles of the mean streamwise and vertical velocity components and of the Reynolds shear stress distribution. To further quantify the differences in turbulent structure under various surface roughnesses, a quadrant analysis was performed. 相似文献
146.
IP over optical networks: architectural aspects 总被引:10,自引:0,他引:10
Rajagopalan B. Pendarakis D. Saha D. Ramamoorthy R.S. Bala K. 《Communications Magazine, IEEE》2000,38(9):94-102
The Internet transport infrastructure is moving toward a model of high-speed routers interconnected by intelligent optical core networks. A consensus is emerging in the industry on utilizing an IP-centric control plane within optical networks to support dynamic provisioning and restoration of lightpaths. At the same time, there are divergent views on how IP routers must interact with optical core networks to achieve end-to-end connectivity. This article describes the architectural alternatives for interconnecting IP routers over optical networks, considering the routing and signaling issues. Also, the application of IP-based protocols for dynamic provisioning and restoration of lightpaths, as well as the interworking of multivendor optical networks is described 相似文献
147.
Superalloy, Inconel 718 is widely used in the sophisticated applications due to its unique properties. However, machining
of such superior material is difficult and costly due its peculiar characteristics. The present article is an attempt to suggest
Taguchi optimization technique to study the machinability of Inconel 718 with respect to cutting force, cutting temperature,
and tool life in high speed turning of Inconel 718 using cemented tungsten carbide (K20) cutting tool. Therefore, the objective
of this work is divided into two phases: (i) to demonstrate a correlation between cutting speed, feed, and depth of cut with
respect to cutting force, cutting temperature, and tool life in a process control of high speed turning of Inconel 718 in
order to identify the optimum combination of cutting parameters; (ii) to show the effect of high speed cutting parameters
on the tool wear mechanism and chip analysis. These correlations were obtained by multiple linear regressions. The confirmation
tests were carried out to make a comparison between the experimental results and mathematical models proposed. The proposed
models agree well with the experimental results. 相似文献
148.
Hanne Hjorth Te?nnesen Jan Karlsen Anne -Lise Grislingaas Korattiyil Velayudhan Nair Balakrishnan Payyeri Ayyappan James Verghese 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,194(6):570-572
Summary Three varieties ofCurcuma longa andC. aromatica were investigated during a growth period of 17 weeks with respect to the content of curcuminoids in the bulbs and fingers. A decrease in pigment production as a function of maturity of the rhizomes was observed. The total content of curcuminoids was equal inC. longa andC. aromatica, but with a slight difference in distribution between the fingers and bulbs in the two species. Taking the biomass into account, the fingers will be more beneficial for the isolation of curcuminoids than the respective bulbs.
Studien über Curcumin und Curcuminoide XXI. Unterschiede des Gehaltes an Curcuminoiden bei Curcuma longa L. und Curcuma aromatica Salisb. aus Indien während einer Saison
Zusammenfassung Drei Typen vonCurcuma longa undC. aromatica wurden während einer Wachstumsperiode von 17 Wochen auf ihren Curcuminoidgehalt in den Knollen und im Wurzelstock untersucht. Eine Abnahme der Pigmentproduktion in Abhängigkeit von dem Entwicklungsstadium der Rhizome wurde festgestellt. Der Gesamtgehalt an Curcuminoiden beiC. longa undC. aromatica war der gleiche, doch bestand ein geringer Unterschied in der Verteilung dieser zwischen Knolle und Wurzelstock bei den beiden Spezies. Bei Betrachtung der Biomasse ist der Wurzelstock für die Isolation von Curcuminoiden besser geeignet als die Knollen.相似文献
149.
The present work focuses mainly on an in vivo evaluation of ultra fine grained titanium(UFG-Ti) obtained by severe plastic deformation(SPD).The SPD on commercially produced Grade 2 titanium(Cp-Ti) resulted in the refinement of the grain size by several orders of magnitude.Polished surfaces having similar roughness from both UFG-Ti and Cp-Ti were prepared.In vitro test revealed the presence of fibronectin,which was involved in the attachment of the cells to the substrate.Phase contrast micrographs showed the... 相似文献
150.
Chu-Yin Chang Anthony A. Maciejewski Venkataramanan Balakrishnan Rodney G. Roberts Kishor Saitwal 《Pattern Analysis & Applications》2007,10(1):15-31
Eigendecomposition-based techniques are popular for a number of computer vision problems, e.g., object and pose estimation,
because they are purely appearance based and they require few on-line computations. Unfortunately, they also typically require
an unobstructed view of the object whose pose is being detected. The presence of occlusion and background clutter precludes
the use of the normalizations that are typically applied and significantly alters the appearance of the object under detection.
This work presents an algorithm that is based on applying eigendecomposition to a quadtree representation of the image dataset
used to describe the appearance of an object. This allows decisions concerning the pose of an object to be based on only those
portions of the image in which the algorithm has determined that the object is not occluded. The accuracy and computational
efficiency of the proposed approach is evaluated on 16 different objects with up to 50% of the object being occluded and on
images of ships in a dockyard.
Chu-Yin Chang received the B.S. degree in mechanical engineering from National Central University, Chung-Li, Taiwan, ROC, in 1988, the M.S. degree in electrical engineering from the University of California, Davis, in 1993, and the Ph.D. degree in electrical and computer engineering from Purdue University, West Lafayette, in 1999. From 1999--2002, he was a Machine Vision Systems Engineer with Semiconductor Technologies and Instruments, Inc., Plano, TX. He is currently the Vice President of Energid Technologies, Cambridge, MA, USA. His research interests include computer vision, computer graphics, and robotics. Anthony A. Maciejewski received the BSEE, M.S., and Ph.D. degrees from Ohio State University in 1982, 1984, and 1987. From 1988 to 2001, he was a professor of Electrical and Computer Engineering at Purdue University, West Lafayette. He is currently the Department Head of Electrical and Computer Engineering at Colorado State University. He is a Fellow of the IEEE. A complete vita is available at: Venkataramanan Balakrishnan is Professor and Associate Head of Electrical and Computer Engineering at Purdue University, West Lafayette, Indiana. He received the B.Tech degree in electronics and communication and the President of India Gold Medal from the Indian Institute of Technology, Madras, in 1985. He then attended Stanford University, where he received the M.S. degree in statistics and the Ph.D. degree in electrical engineering in 1992. He joined Purdue University in 1994 after post-doctoral research at Stanford, CalTech and the University of Maryland. His primary research interests are in convex optimization and large-scale numerical algebra, applied to engineering problems. Rodney G. Roberts received B.S. degrees in Electrical Engineering and Mathematics from Rose-Hulman Institute of Technology in 1987 and an MSEE and Ph.D. in Electrical Engineering from Purdue University in 1988 and 1992, respectively. From 1992 until 1994, he was a National Research Council Fellow at Wright Patterson Air Force Base in Dayton, Ohio. Since 1994 he has been at the Florida A&M University---Florida State University College of Engineering where he is currently a Professor of Electrical and Computer Engineering. His research interests are in the areas of robotics and image processing. Kishor Saitwal received the Bachelor of Engineering (B.E.) degree in Instrumentation and Controls from Vishwakarma Institute of Technology, Pune, India, in 1998. He was ranked Third in the Pune University and was recipient of National Talent Search scholarship. He received the M.S. and Ph.D. degrees from the Electrical and Computer Engineering department, Colorado State University, Fort Collins, in 2001 and 2006, respectively. He is currently with Behavioral Recognition Systems, Inc. performing research in computer aided video surveillance systems. His research interests include image/video processing, computer vision, and robotics. 相似文献
Anthony A. MaciejewskiEmail: |
Chu-Yin Chang received the B.S. degree in mechanical engineering from National Central University, Chung-Li, Taiwan, ROC, in 1988, the M.S. degree in electrical engineering from the University of California, Davis, in 1993, and the Ph.D. degree in electrical and computer engineering from Purdue University, West Lafayette, in 1999. From 1999--2002, he was a Machine Vision Systems Engineer with Semiconductor Technologies and Instruments, Inc., Plano, TX. He is currently the Vice President of Energid Technologies, Cambridge, MA, USA. His research interests include computer vision, computer graphics, and robotics. Anthony A. Maciejewski received the BSEE, M.S., and Ph.D. degrees from Ohio State University in 1982, 1984, and 1987. From 1988 to 2001, he was a professor of Electrical and Computer Engineering at Purdue University, West Lafayette. He is currently the Department Head of Electrical and Computer Engineering at Colorado State University. He is a Fellow of the IEEE. A complete vita is available at: Venkataramanan Balakrishnan is Professor and Associate Head of Electrical and Computer Engineering at Purdue University, West Lafayette, Indiana. He received the B.Tech degree in electronics and communication and the President of India Gold Medal from the Indian Institute of Technology, Madras, in 1985. He then attended Stanford University, where he received the M.S. degree in statistics and the Ph.D. degree in electrical engineering in 1992. He joined Purdue University in 1994 after post-doctoral research at Stanford, CalTech and the University of Maryland. His primary research interests are in convex optimization and large-scale numerical algebra, applied to engineering problems. Rodney G. Roberts received B.S. degrees in Electrical Engineering and Mathematics from Rose-Hulman Institute of Technology in 1987 and an MSEE and Ph.D. in Electrical Engineering from Purdue University in 1988 and 1992, respectively. From 1992 until 1994, he was a National Research Council Fellow at Wright Patterson Air Force Base in Dayton, Ohio. Since 1994 he has been at the Florida A&M University---Florida State University College of Engineering where he is currently a Professor of Electrical and Computer Engineering. His research interests are in the areas of robotics and image processing. Kishor Saitwal received the Bachelor of Engineering (B.E.) degree in Instrumentation and Controls from Vishwakarma Institute of Technology, Pune, India, in 1998. He was ranked Third in the Pune University and was recipient of National Talent Search scholarship. He received the M.S. and Ph.D. degrees from the Electrical and Computer Engineering department, Colorado State University, Fort Collins, in 2001 and 2006, respectively. He is currently with Behavioral Recognition Systems, Inc. performing research in computer aided video surveillance systems. His research interests include image/video processing, computer vision, and robotics. 相似文献