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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Reproductive health and denied paternity : the politics of men's fertility.

Chauke, Polite 04 September 2014 (has links)
Issues of fertility, population growth and birth control are synonymous with women. Therefore, there is a void of the male perspective on issues pertaining to reproductive health. There is a reproductive health discourse, in which bio-psychosocial service such as family planning is woman-based. Whilst on the other hand statistics on absent fathers and contested pregnancies, are reaching millions and thus the effectiveness of these services are questionable. Therefore, men’s health and sexuality requires careful understanding so as to unfold narrations of denied paternity and men’s ‘assumed’ lack of responsibility in questions of contraception. Through in-depth interviews with 14 unmarried men from the townships of Soweto and Kagiso, this research found that contraception is a gendered concept that constructs various experiences for men in how they perceive sexual reproductive health services. It also found that denied paternity and father absences are rooted not only in historical factors but also in feminised conceptions of contraception and how this conception speaks to notions of how responsibility is distributed and withheld. Furthermore, it acknowledges that there are different conceptions of denied paternity and father absence and thus, shapes men’s experiences and expectations of fatherhood. Finally, it argues that masculine sexualities, notions of pleasure and issues of fertility are shaped by sexual socialisation processes; this also links how men transition from boyhood to manhood through circumcision and initiation schools not only as a cultural and religious practice but as a health practice. These narratives were captured through using thematic content analysis in investigating unmarried men’s perceptions of contraceptives and ideas of father absence and denied paternity. This research contributes to the existing knowledge on family and children services, with specific attention to family planning and the provision of services to young men and women regarding reproductive rights and responsibilities.
2

Development of a Velocity Controller for Following a Human Using Target Velocity in GPS-Denied Environments

Hartman, Chase January 2018 (has links)
No description available.
3

GPS Denied Localization Using Ultra-Wideband Radios

Vanfleet, Joshua P. 01 August 2018 (has links)
GPS denied environments cause each unmanned ground vehicle (UGV) in an autonomous convoy to lose positional accuracy which can lead to inoperability, or even damage. In order for autonomous convoy systems to fill the needs of any particular field, a well-performing system must be designed such that a convoy can operate in any environment. Ultra-wideband (UWB) radios are a proposed solution to GPS denied localization.The main objective of this research is to use UWB radios to localize a leader vehicle within a convoy situation while in a GPS denied environment.
4

Impacts of Distributions and Trajectories on Navigation Uncertainty Using Line-of-Sight Measurements to Known Landmarks in GPS-Denied Environments

Lamoreaux, Ryan D. 01 December 2017 (has links)
Unmanned vehicles are increasingly common in our world today. Self-driving ground vehicles and unmanned aerial vehicles (UAVs) such as quadcopters have become the fastest growing area of automated vehicles research. These systems use three main processes to autonomously travel from one location to another: guidance, navigation, and controls (GNC). Guidance refers to the process of determining a desired path of travel or trajectory, affecting velocities and orientations. Examples of guidance activities include path planning and obstacle avoidance. Effective guidance decisions require knowledge of one’s current location. Navigation systems typically answer questions such as: “Where am I? What is my orientation? How fast am I going?” Finally, the process is tied together when controls are implemented. Controls use navigation estimates (e.g., “Where I am now?”) and the desired trajectory from guidance processes (e.g., “Where do I want to be?”) to control the moving parts of the system to accomplish relevant goals. Navigation in autonomous vehicles involves intelligently combining information from several sensors to produce accurate state estimations. To date, global positioning systems(GPS) occupy a crucial place in most navigation systems. However, GPS is not universally reliable. Even when available, GPS can be easily spoofed or jammed, rendering it useless. Thus, navigation within GPS-denied environments is an area of deep interest in both military and civilian applications. Image-aided inertial navigation is an alternative navigational solution in GPS-denied environments. One form of image-aided navigation measures the bearing from the vehicle to a feature or landmark of known location using a single lens imager, such as a camera, to deduce information about the vehicle’s position and attitude. This work uncovers and explores several of the impacts of trajectories and land mark distributions on the navigation information gained from this type of aiding measurement. To do so, a modular system model and extended Kalman filter (EKF) are described and implemented. A quadrotor system model is first presented. This model is implemented and then used to produce sensor data for several trajectories of varying shape, altitude, and landmark density. Next, navigation data is produced by running the sensor data through an EKF. The data is plotted and examined to determine effects of each variable. These effects are then explained. Finally, an equation describing the quantity of information in each measurement is derived and related to the patterns seen in the data. The resulting equation is then used to explain selected patterns in the data. Other uses of this equation are presented, including applications to path planning and landmark placement.
5

Multiple Agent Target Tracking in GPS-Denied Environments

Tolman, Skyler 17 December 2019 (has links)
Unmanned aerial systems (UAS) are effective for surveillance and monitoring, but struggle with persistent, long-term tracking, especially without GPS, due to limited flight time. Persistent tracking can be accomplished using multiple vehicles if one vehicle can effectively hand off the tracking information to another replacement vehicle. This work presents a solution to the moving-target handoff problem in the absence of GPS. The proposed solution (a) a nonlinear complementary filter for self-pose estimation using only an IMU, (b) a particle filter for relative pose estimation between UAS using a relative range (c) visual target tracking using a gimballed camera when the target is close to the handoff UAS, and (d) track correlation logic using Procrustes analysis to perform the final target handoff between vehicles. We present hardware results of the self-pose estimation and visual target tracking, as well as an extensive simulation result that demonstrates the effectiveness of our full system, and perform Monte-Carlo simulations that indicate a 97% successful handoff rate using the proposed methods.
6

UTILIZING BEHAVIOR INTERVENTIONS TO INCREASE APPROPRIATE WAITING BEHAVIOR WITH INDIVIDUALS DIAGNOSED WITH ASD: A REVIEW OF THE LITERATURE

Markovich, Abigail January 2020 (has links)
Children diagnosed with Autism Spectrum Disorder (ASD) often engage in impulsive, dysfunctional, and maladaptive behaviors (Dawson, Matson, & Cherry, 1998). Research has shown the individuals diagnosed with ASD often exhibit problem behavior when they are required to wait for a preferred item. In fact, research has demonstrated that individuals diagnosed with ASD often choose smaller, immediate reinforcer over larger, delayed reinforcer. Most of the research conducted, however, has previously focused on teaching waiting for a preferred item within the ADHD population. The purpose of the current literature review was to evaluate recent research utilizing behavior interventions to increase socially appropriate waiting with individuals diagnosed with ASD. This review assessed the age of participants, setting(s), research design, independent variables, results, and effectiveness. This review also evaluated the rigor of those studies included utilizing the Quality and Rigor Checklist (Ledford, Lane, & Tate, 2018). Lastly, this review provides recommendations to clinicians currently practicing with the field. / Applied Behavioral Analysis
7

Modeling, Parameter Estimation, and Navigation of Indoor Quadrotor Robots

Quebe, Stephen C. 29 April 2013 (has links) (PDF)
This thesis discusses topics relevant to indoor unmanned quadrotor navigation and control. These topics include: quadrotor modeling, sensor modeling, quadrotor parameter estimation, sensor calibration, quadrotor state estimation using onboard sensors, and cooperative GPS navigation. Modeling the quadrotor, sensor modeling, and parameter estimation are essential components for quadrotor navigation and control. This thesis investigates prior work and organizes a wide variety of models and calibration methods that enable indoor unmanned quadrotor flight. Quadrotor parameter estimation using a particle filter is a contribution that extends current research in the area. This contribution is novel in that it applies the particle filter specifically to quadrotor parameter estimation as opposed to quadrotor state estimation. The advantages and disadvantages of such an approach are explained. Quadrotor state estimation using onboard sensors and without the aid of GPS is also discussed, as well as quadrotor pose estimation using the Extended Kalman Filter with an inertial measurement unit and simulated 3D camera updates. This is done using two measurement updates: one from the inertial measurement unit and one from the simulated 3D camera. Finally, we demonstrate that when GPS lock cannot be obtained by an unmanned vehicle individually. A group of cooperative robots with pose estimates to one anther can exploit partial GPS information to improve global position estimates for individuals in the group. This method is advantageous for robots that need to navigate in environments where signals from GPS satellites are partially obscured or jammed.
8

Möten mellan gömda flyktingar och sjukvårdspersonal / Meeting of hidden refugees and medical personnel

Mohamadi, Sahar January 2014 (has links)
The purpose of this essay is to understand meeting between hidden refugees and health professionals through interviews with refugee in hiding and health professionals. The implantation of the essay has been made by social science research methods which I have used as a qualitative survey. The material that I have used in this paper is to interview with hidden refugee and health care workers. I have used the different sources such as literature, internet and different laws which relates to the topic of this easy. I am using the power of theories to analyze the work. The work highlights relation between healthcare professionals and hidden refugees. The work is based on a new law that called SFS and that is health care for some foreigners who reside in Sweden without the necessary of permeation which according to the Social Board (2010) gives the hidden and undocumented person entitled to care that cannot be deferred. The result of my investigation was that hidden refugee’s right to emergency cares is not always met in practice although they are legally entitled to it. Another result was that the hidden meeting with health care professionals is not problem in itself but being refused to care is problematic . Controlled documents from health professionals page allows hidden may feel at a disadvantage. In this case crated anxiety and fear among the hidden people seeking care .This means that they seek care at nonprofit organizations instead. Conclusions about my essay is that a more clear legislation should be enacted and that healthcare professionals should be payable after care needs and not by legal status and ability to pay.
9

Autonomous Goal-Based Mapping and Navigation Using a Ground Robot

Ferrin, Jeffrey L. 01 December 2016 (has links)
Ground robotic vehicles are used in many different applications. Many of these uses include tele-operation of the robot. This allows the robot to be deployed in locations that are too difficult or are unsafe for human access. The ability of a ground robot to autonomously navigate to a desired location without a-priori map information and without using GPS would allow robotic vehicles to be used in many of these situations and would free the operator to focus on other more important tasks. The purpose of this research is to develop algorithms that enable a ground robot to autonomously navigate to a user-selected location. The goal is selected from a video feed from the robot and the robot drives to the goal location while avoiding obstacles. The method uses a monocular camera for measuring the locations of the goal and landmarks. The method is validated in simulation and through experiments on an iRobot Packbot platform. A novel goal-based robocentric mapping algorithm is derived in Chapter 3. This map is created using an extended Kalman filter (EKF) by tracking the position of the goal along with other available landmarks surrounding the robot as it drives towards the goal. The mapping is robocentric, meaning that the map is a local map created in the robot-body frame. A unique state definition of the goal states and additional landmarks is presented that improves the estimate of the goal location. An improved 3D model is derived and used to allow the robot to drive on non-flat terrain while calculating the position of the goal and other landmarks. The observability and consistency of the proposed method are shown in Chapter 4. The visual tracking algorithm is explained in Chapter 5. This tracker is used with the EKF to improve tracking performance and to allow the objects to be tracked even after leaving the camera field of view for significant periods of time. This problem presents a difficult challenge for visual tracking because of the drastic change in size of the goal object as the robot approaches the goal. The tracking method is validated through experiments in real-world scenarios. The method of planning and control is derived in Chapter 6. A Model Predictive Control (MPC) formulation is designed that explicitly handles the sensor constraints of a monocular camera that is rigidly mounted to the vehicle. The MPC uses an observability-based cost function to drive the robot along a path that minimizes the position error of the goal in the robot-body frame. The MPC algorithm also avoids obstacles while driving to the goal. The conditions are explained that guarantee the robot will arrive within some specified distance of the goal. The entire system is implemented on an iRobot Packbot and experiments are conducted and presented in Chapter 7. The methods described in this work are shown to work on actual hardware allowing the robot to arrive at a user-selected goal in real-world scenarios.
10

Inertial Navigation Sytem Improvement Using Ground Station Data

Guner, Dunya Rauf Levent 01 September 2012 (has links) (PDF)
Missile navigation systems rely on hybrid INS/GPS systems to employ lower grade inertial sensors for the sake of cost and availability. Current inertial navigation systems on missiles can perform accurately for a limited time without GPS aiding. However, GPS is the most likely system that is going to be jammed in a crisis or war by low cost jammers by any opposing force. Missiles do not have adequate equipment to maintain accuracy when GPS is jammed completely in the battle area. In this thesis, a new method is proposed to improve performance of INS systems onboard missiles and autonomous aerial vehicles with EO sensors in a GPS denied environment. Previously laid ground based beacons are used by the missile EO/IIR seeker for bearing-only measurements and position updates are performed by the use of modified artillery survey algorithms based on triangulation techniques which involve angle measurements. For mission planning, two main problems are identified as deployment problem and path planning problem and a tool for the optimal laying of beacons for a given desired trajectory and optimal path planning for a given network of beacons is developed by using evolutionary algorithms and results for test scenarios are discussed.

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