In this paper, we present development and testing results for a novel colonic polyp classificatio... more In this paper, we present development and testing results for a novel colonic polyp classification method for use as part of a computed tomographic colonography (CTC) computer-aided detection (CAD) system. Inspired by the interpretative methodology of radiologists using 3-D fly-through mode in CTC reading, we have developed an algorithm which utilizes sequences of images (referred to here as videos) for classification of CAD marks. For each CAD mark, we created a video composed of a series of intraluminal, volume-rendered images visualizing the detection from multiple viewpoints. We then framed the video classification question as a multiple-instance learning (MIL) problem. Since a positive (negative) bag may contain negative (positive) instances, which in our case depends on the viewing angles and camera distance to the target, we developed a novel MIL paradigm to accommodate this class of problems. We solved the new MIL problem by maximizing a L2-norm soft margin using semidefinite programming, which can optimize relevant parameters automatically. We tested our method by analyzing a CTC data set obtained from 50 patients from three medical centers. Our proposed method showed significantly better performance compared with several traditional MIL methods. Index Terms-Computed tomographic colonography (CTC), multiple-instance learning, semidefinite programming, video analysis. I. INTRODUCTION C OLON cancer is the second leading cause of cancer-related death in the United States [1]. Computed tomographic colonography (CTC), also known as virtual colonoscopy when a fly-through viewing mode is used, provides a less invasive alternative to optical colonoscopy Manuscript
Due to its importance and possible applications in visualization, tumor detection and pre-operati... more Due to its importance and possible applications in visualization, tumor detection and pre-operative planning, automatic small bowel segmentation is essential for computer-aided diagnosis of small bowel pathology. However, segmenting the small bowel directly on CT scans is very difficult because of the low image contrast on CT scans and high tortuosity of the small bowel and its close proximity to other abdominal organs. Motivated by the intensity characteristics of abdominal CT images, the anatomic relationship between the mesenteric vasculature and the small bowel, and potential usefulness of the mesenteric vasculature for establishing the path of the small bowel, we propose a novel mesenteric vasculature map-guided method for small bowel segmentation on high-resolution CT angiography scans. The major mesenteric arteries are first segmented using a vessel tracing method based on multi-linear subspace vessel model and Bayesian inference.
We present a new approach for retrieving halo-free phase contrast microscopy (hfPC) images by upg... more We present a new approach for retrieving halo-free phase contrast microscopy (hfPC) images by upgrading the conventional PC microscope with an external interferometric module, which generates sufficient data for reversing the halo artifact. Acquiring four independent intensity images, our approach first measures haloed phase maps of the sample. We solve for the halo-free sample transmission function by using a physical model of the image formation under partial spatial coherence. Using this halo-free sample transmission, we can numerically generate artifact-free PC images. Furthermore, this transmission can be further used to obtain quantitative information about the sample, e.g., the thickness with known refractive indices, dry mass of live cells during their cycles. We tested our hfPC method on various control samples, e.g., beads, pillars and validated its potential for biological investigation by imaging live HeLa cells, red blood cells, and neurons.
2015 IEEE International Workshop on Information Forensics and Security (WIFS), 2015
With the rapid growth of Internet traffic, new emerging network architectures are under deploymen... more With the rapid growth of Internet traffic, new emerging network architectures are under deployment. Those architectures will substitute the current IP/TCP network only if they can ensure better security. Currently, the most advanced proposal for future Internet architecture is Named Data Networking (NDN). However, new computer network architectures bring new types of attacks. This paper focuses on the detection against Interest flooding-one of the most threatening attacks in NDN. The statistical detection is studied within the framework of hypothesis testing. First, we address the case in which all traffic parameters are known. In this context, the optimal test is designed and its statistical performance is given. This allows us to provide an upper bound on the highest detection accuracy one can expect. Then, a linear parametric model is proposed to estimate unknown parameters and to design a practical test for which the statistical performance is also provided. Numerical results show the relevance of the proposed methodology.
2015 IFIP/IEEE International Symposium on Integrated Network Management (IM), 2015
Confronting the changing demand of users, the current Internet is revealing its limitations. Info... more Confronting the changing demand of users, the current Internet is revealing its limitations. Information Centric Network (ICN) are Future Internet proposals which are based on named data objects. In order to actually replace its predecessor, ICN must be able to resist existent threats in the current Internet, especially the Denial of Service (DoS) attack. In this paper, we focus on Interest flooding-a new type of DoS attack in Content Centric Network (CCN). Several solutions for this threat have been introduced, but they do not solve the problem in a satisfying way because of some drawbacks in either their detection performance, scalability support or restricted scenario of usage. Our goal is to design a reliable, low resources-consuming detection method against Interest flooding attack in CCN. A detection scheme must be attended since a lot of resources consumed by unnecessarily continuous countermeasure can be saved by a dependable detector. Like no other detectors in proposed solutions, our detector is based on statistical hypotheses testing theory. The achieved result is a low resources-consuming detector that can be deployed globally on each CCN router. The false alarm probability of our detector can be controlled at will. Its statistical power can be theoretically established and evaluated precisely. To validate our contribution, numerical results show the relevance of the proposed approach and the sharpness of theoretical results.
Isotropic ultra-thin shells or membranes, as well as cable–membrane structures, cannot resist loa... more Isotropic ultra-thin shells or membranes, as well as cable–membrane structures, cannot resist loads at the initial state and always require a form-finding process to reach the steady state. After this stage, they can work in a pure membrane state and quickly experience large deflection behavior, even with a small amplitude of load. This paper aims to improve the load-carrying capacity and strength of membrane structures via exploiting the advantages of functionally graded carbon-nanotube-reinforced composite (FG-CNTRC) material. In this work, the load-carrying capacity and nonlinear behavior of membrane structures with and without CNTs reinforcement are first investigated using a unified adaptive approach (UAA). As an advantage of UAA, both form finding and postbuckling analysis are performed conveniently and simultaneously based on a modified Riks method. Different from the classical membrane theory, the present theory (first-order shear deformation theory) simultaneously takes int...
MILCOM 2012 - 2012 IEEE Military Communications Conference, 2012
Due to the challenging network conditions posed by a highly-dynamic airborne telemetry environmen... more Due to the challenging network conditions posed by a highly-dynamic airborne telemetry environment, it is essential for the transport protocol to provide automated mechanisms that dynamically adapt to changing end-to-end performance on any path. The AeroTP multi-mode transport protocol provides service tailored to the requirements of the telemetry mission control and data packets, achieving better performance compared to the traditional TCP and UDP. We use ns-3 to simulate the AeroTP protocol's reliable and quasi-reliable modes and demonstrate the performance tradeoffs between the modes, as well as comparing their performance with TCP and UDP.
Due to the challenging network conditions posed by a highly-dynamic airborne telemetry environmen... more Due to the challenging network conditions posed by a highly-dynamic airborne telemetry environment, it is essential for the transport protocol to provide automated mechanisms that dynamically adapt to changing end-to-end performance on any path. The AeroTP multi-mode transport protocol provides service tailored to the requirements of the telemetry mission control and data packets, achieving better performance compared to the traditional TCP and UDP. We use ns-3 to simulate the AeroTP protocol's reliable and quasi-reliable modes and demonstrate the performance tradeoffs between the modes, as well as comparing their performance with TCP and UDP.
In this paper, a rigorous analysis of the performance of time-switching energy harvesting strateg... more In this paper, a rigorous analysis of the performance of time-switching energy harvesting strategy that is applied for a half-duplex bidirectional wireless sensor network with intermediate relay over a Rician fading channel is presented to provide the exact-form expressions of the outage probability, achievable throughput and the symbol-error-rate (SER) of the system under the hardware impairment condition. Using the proposed probabilistic models for wireless channels between mobile nodes as well as for the hardware noises, we derive the outage probability of the system, and then the throughput and SER can be obtained as a result. Both exact analysis and asymptotic analysis at high signal-power-to-noise-ratio regime are provided. Monte Carlo simulation is also conducted to verify the analysis. This work confirms the effectiveness of energy harvesting applied in wireless sensor networks over a Rician fading channel, and can provide an insightful understanding about the effect of vari...
2011 IEEE International Symposium on Biomedical Imaging: From Nano to Macro, 2011
In this paper, we proposed a novel method to improve colonic polyp detection in computed tomograp... more In this paper, we proposed a novel method to improve colonic polyp detection in computed tomographic colonography. Utilizing the human knowledge workers via the Amazon Mechanical Turk (MTurk) webservice, we distributed polyp detections from a computer-aided detection system (CAD) to anonymous online knowledge workers and asked them to distinguish true and false polyp candidates. We combined decisions from the CAD
In this paper, we present development and testing results for a novel colonic polyp classificatio... more In this paper, we present development and testing results for a novel colonic polyp classification method for use as part of a computed tomographic colonography (CTC) computer-aided detection (CAD) system. Inspired by the interpretative methodology of radiologists using 3-D fly-through mode in CTC reading, we have developed an algorithm which utilizes sequences of images (referred to here as videos) for classification of CAD marks. For each CAD mark, we created a video composed of a series of intraluminal, volume-rendered images visualizing the detection from multiple viewpoints. We then framed the video classification question as a multiple-instance learning (MIL) problem. Since a positive (negative) bag may contain negative (positive) instances, which in our case depends on the viewing angles and camera distance to the target, we developed a novel MIL paradigm to accommodate this class of problems. We solved the new MIL problem by maximizing a L2-norm soft margin using semidefinite programming, which can optimize relevant parameters automatically. We tested our method by analyzing a CTC data set obtained from 50 patients from three medical centers. Our proposed method showed significantly better performance compared with several traditional MIL methods. Index Terms-Computed tomographic colonography (CTC), multiple-instance learning, semidefinite programming, video analysis. I. INTRODUCTION C OLON cancer is the second leading cause of cancer-related death in the United States [1]. Computed tomographic colonography (CTC), also known as virtual colonoscopy when a fly-through viewing mode is used, provides a less invasive alternative to optical colonoscopy Manuscript
Due to its importance and possible applications in visualization, tumor detection and pre-operati... more Due to its importance and possible applications in visualization, tumor detection and pre-operative planning, automatic small bowel segmentation is essential for computer-aided diagnosis of small bowel pathology. However, segmenting the small bowel directly on CT scans is very difficult because of the low image contrast on CT scans and high tortuosity of the small bowel and its close proximity to other abdominal organs. Motivated by the intensity characteristics of abdominal CT images, the anatomic relationship between the mesenteric vasculature and the small bowel, and potential usefulness of the mesenteric vasculature for establishing the path of the small bowel, we propose a novel mesenteric vasculature map-guided method for small bowel segmentation on high-resolution CT angiography scans. The major mesenteric arteries are first segmented using a vessel tracing method based on multi-linear subspace vessel model and Bayesian inference.
We present a new approach for retrieving halo-free phase contrast microscopy (hfPC) images by upg... more We present a new approach for retrieving halo-free phase contrast microscopy (hfPC) images by upgrading the conventional PC microscope with an external interferometric module, which generates sufficient data for reversing the halo artifact. Acquiring four independent intensity images, our approach first measures haloed phase maps of the sample. We solve for the halo-free sample transmission function by using a physical model of the image formation under partial spatial coherence. Using this halo-free sample transmission, we can numerically generate artifact-free PC images. Furthermore, this transmission can be further used to obtain quantitative information about the sample, e.g., the thickness with known refractive indices, dry mass of live cells during their cycles. We tested our hfPC method on various control samples, e.g., beads, pillars and validated its potential for biological investigation by imaging live HeLa cells, red blood cells, and neurons.
2015 IEEE International Workshop on Information Forensics and Security (WIFS), 2015
With the rapid growth of Internet traffic, new emerging network architectures are under deploymen... more With the rapid growth of Internet traffic, new emerging network architectures are under deployment. Those architectures will substitute the current IP/TCP network only if they can ensure better security. Currently, the most advanced proposal for future Internet architecture is Named Data Networking (NDN). However, new computer network architectures bring new types of attacks. This paper focuses on the detection against Interest flooding-one of the most threatening attacks in NDN. The statistical detection is studied within the framework of hypothesis testing. First, we address the case in which all traffic parameters are known. In this context, the optimal test is designed and its statistical performance is given. This allows us to provide an upper bound on the highest detection accuracy one can expect. Then, a linear parametric model is proposed to estimate unknown parameters and to design a practical test for which the statistical performance is also provided. Numerical results show the relevance of the proposed methodology.
2015 IFIP/IEEE International Symposium on Integrated Network Management (IM), 2015
Confronting the changing demand of users, the current Internet is revealing its limitations. Info... more Confronting the changing demand of users, the current Internet is revealing its limitations. Information Centric Network (ICN) are Future Internet proposals which are based on named data objects. In order to actually replace its predecessor, ICN must be able to resist existent threats in the current Internet, especially the Denial of Service (DoS) attack. In this paper, we focus on Interest flooding-a new type of DoS attack in Content Centric Network (CCN). Several solutions for this threat have been introduced, but they do not solve the problem in a satisfying way because of some drawbacks in either their detection performance, scalability support or restricted scenario of usage. Our goal is to design a reliable, low resources-consuming detection method against Interest flooding attack in CCN. A detection scheme must be attended since a lot of resources consumed by unnecessarily continuous countermeasure can be saved by a dependable detector. Like no other detectors in proposed solutions, our detector is based on statistical hypotheses testing theory. The achieved result is a low resources-consuming detector that can be deployed globally on each CCN router. The false alarm probability of our detector can be controlled at will. Its statistical power can be theoretically established and evaluated precisely. To validate our contribution, numerical results show the relevance of the proposed approach and the sharpness of theoretical results.
Isotropic ultra-thin shells or membranes, as well as cable–membrane structures, cannot resist loa... more Isotropic ultra-thin shells or membranes, as well as cable–membrane structures, cannot resist loads at the initial state and always require a form-finding process to reach the steady state. After this stage, they can work in a pure membrane state and quickly experience large deflection behavior, even with a small amplitude of load. This paper aims to improve the load-carrying capacity and strength of membrane structures via exploiting the advantages of functionally graded carbon-nanotube-reinforced composite (FG-CNTRC) material. In this work, the load-carrying capacity and nonlinear behavior of membrane structures with and without CNTs reinforcement are first investigated using a unified adaptive approach (UAA). As an advantage of UAA, both form finding and postbuckling analysis are performed conveniently and simultaneously based on a modified Riks method. Different from the classical membrane theory, the present theory (first-order shear deformation theory) simultaneously takes int...
MILCOM 2012 - 2012 IEEE Military Communications Conference, 2012
Due to the challenging network conditions posed by a highly-dynamic airborne telemetry environmen... more Due to the challenging network conditions posed by a highly-dynamic airborne telemetry environment, it is essential for the transport protocol to provide automated mechanisms that dynamically adapt to changing end-to-end performance on any path. The AeroTP multi-mode transport protocol provides service tailored to the requirements of the telemetry mission control and data packets, achieving better performance compared to the traditional TCP and UDP. We use ns-3 to simulate the AeroTP protocol's reliable and quasi-reliable modes and demonstrate the performance tradeoffs between the modes, as well as comparing their performance with TCP and UDP.
Due to the challenging network conditions posed by a highly-dynamic airborne telemetry environmen... more Due to the challenging network conditions posed by a highly-dynamic airborne telemetry environment, it is essential for the transport protocol to provide automated mechanisms that dynamically adapt to changing end-to-end performance on any path. The AeroTP multi-mode transport protocol provides service tailored to the requirements of the telemetry mission control and data packets, achieving better performance compared to the traditional TCP and UDP. We use ns-3 to simulate the AeroTP protocol's reliable and quasi-reliable modes and demonstrate the performance tradeoffs between the modes, as well as comparing their performance with TCP and UDP.
In this paper, a rigorous analysis of the performance of time-switching energy harvesting strateg... more In this paper, a rigorous analysis of the performance of time-switching energy harvesting strategy that is applied for a half-duplex bidirectional wireless sensor network with intermediate relay over a Rician fading channel is presented to provide the exact-form expressions of the outage probability, achievable throughput and the symbol-error-rate (SER) of the system under the hardware impairment condition. Using the proposed probabilistic models for wireless channels between mobile nodes as well as for the hardware noises, we derive the outage probability of the system, and then the throughput and SER can be obtained as a result. Both exact analysis and asymptotic analysis at high signal-power-to-noise-ratio regime are provided. Monte Carlo simulation is also conducted to verify the analysis. This work confirms the effectiveness of energy harvesting applied in wireless sensor networks over a Rician fading channel, and can provide an insightful understanding about the effect of vari...
2011 IEEE International Symposium on Biomedical Imaging: From Nano to Macro, 2011
In this paper, we proposed a novel method to improve colonic polyp detection in computed tomograp... more In this paper, we proposed a novel method to improve colonic polyp detection in computed tomographic colonography. Utilizing the human knowledge workers via the Amazon Mechanical Turk (MTurk) webservice, we distributed polyp detections from a computer-aided detection system (CAD) to anonymous online knowledge workers and asked them to distinguish true and false polyp candidates. We combined decisions from the CAD
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