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Millimeter-wave power amplifiers realized in CMOS processes have demonstrated output power and power added efficiency exceeding 20 dBm and 30%, respectively. We describe efforts to achieve high power and high efficiency for mm-wave transmitters and linearize mm-wave PAs in fineline CMOS processes. We will present novel circuit approaches based on Doherty amplifiers and digital pre-distortion of high-power...
This work focuses on automating the task of estimating Polar ice thickness from airborne radar data acquired over Greenland and Antarctica. This process involves the identification and accurate selection of the ice sheet's surface location and interface between the ice sheet and the underlying bedrock for each measurement. Identifying the surface and bedrock locations in the radar imagery enables...
This paper introduces a non-traditional Web search problem, referred to as ??process-based search??, and focuses on the query analysis and formulation of this type of search. Traditional information retrieval models were created based on the assumption that one query can be answered by one document. A query needs to properly specify the topic being requested. Recently published work, referred to as...
This paper introduces a novel approach to solving a certain type of Web search problem. The concept of process-based Web search is proposed and a prototype process-based search engine has been developed and evaluated to help users solve problems more effectively. Unlike traditional Web search engines showing a list of ranked hyperlinks as results, the proposed system searches and displays results...
Functional impairment of the upper limb is a major challenge faced by many stroke survivors. The present study aimed at developing a novel sensory-enhanced robot-aided motor training program and testing its feasibility in stroke rehabilitation. A specially designed robot handle was developed as an attachment to the Inmotion2 robotic system. This handle provided sensory stimulation through pins connected...
The automation of a robot to measure ice sheets is necessary for CReSIS. The approach described in this paper is to use a single camera for localization for use in many types of large-scale environments. In order to operate in large-scale environments, a hybrid map approach has been used; both topological and geometric maps. An appearance-based approach is used for recognizing the different locations...
Mobile robots can perform some of the more dangerous and laborious human tasks on Earth and throughout the solar system, many times with greater efficiency and accuracy, saving both time and resources. As we explore further away from Earth, higher levels of autonomy are also becoming more desired in such applications, one of them being distributed mapping. Smaller, less expensive mobile robots are...
The Center of Remote Sensing of Ice Sheets (CReSIS) is studying the use of the TETwalker mobile robot developed by NASA/Goddard Space Flight Center for polar seismic data acquisition. This paper discusses the design process for deploying seismic sensors within the 4-TETwalker mobile robot architecture. The 4-TETwalkerpsilas center payload node was chosen as the deployment medium. An alternative method...
This paper presents an automated system to assess human vision to identify early signs of vision disorders such as amblyopia (lazy eye), so that potential problems can be addressed as early as possible by having the system refer children to a specialist (pediatric ophthalmologist). The system does not require extensive operator training or patient cooperation. This paper explores the application of...
A calibration-free, high-resolution ADC designed for bioluminescence sensing employs an extended-counting architecture in which the residual error from a second-order incremental SigmaDelta modulator is encoded using a successive approximation ADC. The ADC has been integrated in 0.18-mum CMOS technology and achieves a dynamic range of 90.1 dB and a peak SNDR of 86.3 dB at a conversion rate of 1MSample/sec...
This paper presents a new 32-bit adder structure with 12 GHz low-power operation in 65nm technology. The fast conditional sparse-tree logic (FCSL) is based on modifying the initial sparse-tree architecture (Mathew et al., 2003) to enhance its speed using tertiary trees and applying a carry-select scheme in some of the more significant bits. This design has been compared with the sparse-tree adder...
In this paper, we present the details of a portable, powerful, and flexible software-defined radio development platform called the Kansas University Agile Radio (KUAR). The primary purpose of the KUAR is to enable advanced research in the areas of wireless radio networks, dynamic spectrum access, and cognitive radios. The KUAR hardware implementation and software architecture are discussed in detail...
There are several applications which require high-precision placement of sensors or objects. Unstructured, remote environments make this problem even more complex, where high precision is not attainable using conventional sensors. Some applications have units so sparsely spaced that few options remain. A team of mobile robots can be integrated into such missions, providing a higher level of precision...
This paper examines the use of genetic algorithms and neural networks to generate neural network topologies. The data set consists of digital images of objects taken from different angles. A successful neural network topology had been trained on this data, so it was investigated whether the genetic algorithm could evolve a neural network topology capable of learning the training data. The genetic...
Mobile robots for harsh environments provide useful means for automating the collection of research data in the field by reducing human involvement. MARVIN II has been designed and constructed to autonomously collect radar measurements to determine properties of the polar ice sheets. This paper discusses the lessons learned from a number of field experiments with its predecessor MARVIN, and how these...
The effects of stroke are debilitating on the American population. Past studies of robot-aided motor training for survivors have proven to be effective in upper limb motor recovery. However, survivors also suffer from loss or impairment of sensation. Sensory impairment is an important predictor for motor recovery of stroke survivors. Studies have suggested that sensory inputs during robot-aided motor...
This paper focuses on the assessment of the properties of security enforcement mechanisms for prevention of denial of service (DoS) attacks in wireless sensor networks. First part of the paper demonstrates the requirement for security enforcement using auction theory that allows detection of non cooperative nodes. In the proposed protocol, nodes prefer to participate in forwarding incoming packets...
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