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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.
261

Optimizing Monitoring Efforts of Kit Fox (<em>Vulpes macrotis</em>) in Utah

Richards, Kelsey Alina 01 November 2017 (has links)
The kit fox (Vulpes macrotis) is a species of conservation concern in western North America. Recent methods for monitoring populations of kit fox include using lures and remote cameras in an occupancy-modeling framework and habitat modeling to predict areas of occupancy. In chapter one, we tested the optimal lure and movement procedure for scent stations to maximize visits and detection of foxes, thereby improving estimates of occupancy. Between May 2015 and October 2016, we placed remote cameras at 522 random locations throughout nine study areas in the Colorado Plateau, Great Basin Desert, and Mojave Desert. Each location was randomly assigned one of three methods (Scented Predator Survey Disks, cotton swabs, or hollowed golf ball) to broadcast one of three lure types (Red and Gray Fox liquid lure, Willey liquid lure, and fatty acid lure). After seven nights, half of all stations were moved 100 meters within the same sample grid cell, while the others remained in the same location. Stations were then monitored for an additional week. We used Program MARK and AIC model selection to identify optimal lure types and broadcast methods and to estimate rates of occupancy. Detection of kit foxes differed by method of scent deployment; cotton swabs were associated with the highest rates of visitation. Detection of kit foxes did not differ by lure type. Relocating the scent station after one week did not influence detection probability. We suggest that the use of cotton swabs maximizes detection, and therefore, the precision of estimates of occupancy. For chapter two, we used resource selection functions to identify variables that best discriminated between locations where kit fox were detected and random locations. We then produced a habitat map that predicted the relative probability of kit foxes occurring across seven study areas throughout the state of Utah. We placed remote cameras at 458 randomly selected locations throughout the study areas in the Colorado Plateau, Great Basin Desert, and Mojave Desert. We detected kit foxes at 157 "use" points from these cameras between May 2015 and October 2016. We then compared the attributes of these "use" points to 14,742 available, randomly selected points located within the study areas using variables derived from a Geographic Information System (GIS). We used model selection and minimization of AIC values to determine key habitat characteristics that differentiated use and random locations. We identified slope, elevation, and soil type as significant variables (P < 0.05) in habitat selection of kit foxes. Kit foxes selected areas that were 1) less steep, 2) lower in elevation, and 3) classified as having silty soils. The identification of these specific variables from our modeling effort was generally consistent with kit fox ecology. Our study produced a habitat model that can serve as a foundation for future monitoring efforts of kit foxes in potential habitat across Utah.
262

臺北市立南湖高中學校建築用後評估之研究 / A case study of school building post-occupancy evaluation for Taipei municipal Nanhu high school

戴國禎 Unknown Date (has links)
學校建築佔用最大宗的教育經費與投資,故實施學校建築用後評估,至為重要。台北市尚未有高中對學校建築進行全面用後評估,因此本研究選擇以南湖高中學校建築用後評估為主題。 本研究之目的包含:探討學校建築整體規劃與用後評估之理念與範疇;探究臺北市立南湖高中學校建築整體規劃的理念與過程;研析其學校建築新建完成後的使用情形與使用者的滿意程度;最後提出用後評估的建議,以作為日後改進之參考依據。 本研究使用的研究方法包括文件分析、訪談、調查、觀察等四種方法。以文件分析明瞭南湖高中學校建築之規劃理念。觀察校園內7處定點,訪談南湖高中校長、秘書、主任、教師等7人,以明瞭學校建築使用的情況。問卷調查學生113人,以描述統計、t考驗、F考驗等方法,比較學生在不同性別與不同年級間對學校建築滿意度的差異。 所得研究結論如下:南湖高中學校建築整體規劃的理念以整體性、教育性、舒適性與前瞻性為主。各項設施空間使用情形良好,符合規劃機能與預期效果。教師對壯觀的造型、齊備的教學空間與設施、多樣的活動空間與動靜分明的區分、流暢的動線等項目,尤感滿意。學生對教學空間的大小與使用滿意度最高,性別之間滿意度差異小,各項空間的使用滿意度一、二年級分別高於三年級。師生對使用現況的建議多屬修繕維護與使用行為事項。 本研究依據研究結論,提出建議如下:應推動學校建築用後評估;重視規劃之整體性、教育性、舒適性、與前瞻性;加強部分設施的管理與維護;發展圖書館為教學資源中心;鼓勵教師更充分使用優良的教學設施。以及對後續研究的建議等。 / The purpose of this research is to explore the notions of the total school building planning and the Post-occupancy Evaluation. Illustrated by Taipei Municipal Nanhu High school, the research has inquired into Nanhu High School’s concepts of total school building planning, the space usage condition and user satisfactory. The goal is to propose suggestions for the future use and the improvement. This research is conducted through document analysis, focus interviews, student questionnaire, and campus observation. The conclusions this research has reached and suggestions provided are as follows: (1) ‘The wholeness’, ‘educational’, ‘the comfortableness’ and ‘the foresightedness’ are the main concepts of the total school building planning of Nanhu High School. (2) Each facility and space are well-utilized, conforming to the purpose of design and reaching the planned efficiency. (3) The teachers are significantly satisfied by the spectacular exterior, all-ready teaching spaces plus facilities, various activity spaces, the clear division of mobility and immobility, and the efficient routes. (4) The students are the most satisfied by the size and the usage of the learning space. There is little difference in the satisfactory by gender. The freshmen and the juniors (Year Ten and Year Eleven) reach higher satisfactory of the space usage than the seniors (Year Twelve) in every item. (5) Most of the suggestions from the teachers and the students are about the maintenance and user behaviors. Ultimately, this research, based on the findings and conclusions of the study, proposes following suggestions: (1) It is advised and encouraged to apply Post-occupancy Evaluation. (2) The school building planning should value the wholeness, the educational-ness, the comfortableness and the foresightedness. (3) School should enhance the management and maintenance of certain facilities. (4) School library should develop into the teaching and learning resource centre. (5) Teachers are encouraged to proficiently utilize school’s high quality facilities.
263

Triangulation Based Fusion of Sonar Data with Application in Mobile Robot Mapping and Localization

Wijk, Olle January 2001 (has links)
No description available.
264

Short-Term Occupancy Prediction at the Ottawa Hospital Using Time-Series Data for Admissions and Longitudinal Patient Data for Discharge

Arbuckle, Lon Michel Luk 11 January 2012 (has links)
The Ottawa Hospital cancels hundreds of elective surgeries every year due to a lack of beds, and has an average weekday occupancy rate above 100%. Our approach to addressing these issues, by way of informing administrators of resource needs, was to model the flow of patients coming and going from the hospital. We used administrative data from the Ottawa Hospital to build a time-series model of emergency department admissions, and studied models that would predict next-day discharge of patients currently taking up hospital beds. In the latter, we considered population-averaged models for groups of patients based on their primary medical condition, as well as subject-specific models. We included the random effects from subject-specific variation to improve on predictive accuracy over the population- averaged approach. The result was a model that provided more realistic probabilities of discharge, and stable predictive accuracy over patient length of stay.
265

Short-Term Occupancy Prediction at the Ottawa Hospital Using Time-Series Data for Admissions and Longitudinal Patient Data for Discharge

Arbuckle, Lon Michel Luk 11 January 2012 (has links)
The Ottawa Hospital cancels hundreds of elective surgeries every year due to a lack of beds, and has an average weekday occupancy rate above 100%. Our approach to addressing these issues, by way of informing administrators of resource needs, was to model the flow of patients coming and going from the hospital. We used administrative data from the Ottawa Hospital to build a time-series model of emergency department admissions, and studied models that would predict next-day discharge of patients currently taking up hospital beds. In the latter, we considered population-averaged models for groups of patients based on their primary medical condition, as well as subject-specific models. We included the random effects from subject-specific variation to improve on predictive accuracy over the population- averaged approach. The result was a model that provided more realistic probabilities of discharge, and stable predictive accuracy over patient length of stay.
266

Radar and Thermopile Sensor Fusion for Pedestrian Detection

Rouhani, Shahin January 2005 (has links)
During the last decades, great steps have been taken to decrease passenger fatality in cars. Systems such as ABS and airbags have been developed for this purpose alone. But not much effort has been put into pedestrian safety. In traffic today, pedestrians are one of the most endangered participants and in recent years, there has been an increased demand for pedestrian safety from the European Enhanced Vehicle safety Committee and the European New Car Assessment Programme has thereby developed tests where pedestrian safety is rated. With this, detection of pedestrians has arised as a part in the automotive safety research. This thesis provides some of this research available in the area and a brief introduction to some of the sensors readily available. The objective of this work is to detect pedestrians in front of a vehicle by using thermoelectric infrared sensors fused with short range radar sensors and also to minimize any missed detections or false alarms. There has already been extensive work performed with the thermoelectric infrared sensors for this sole purpose and this thesis is based on that work. Information is provided about the sensors used and an explanation of how they are set up during this work. Methods used for classifying objects are given and the assumptions made about pedestrians in this system. A basic tracking algorithm is used to track radar detected objects in order to provide the fusion system with better data. The approach chosen for the sensor fusion is a central-level fusion where the probabilities for a pedestrian from the radars and the thermoelectric infrared sensors are combined using Dempster-Shafer Theory and accumulated over time in the Occupancy Grid framework. Theories that are extensively used in this thesis are explained in detail and discussed accordingly in different chapters. Finally the experiments undertaken and the results attained from the presented system are shown. A comparison is made with the previous detection system, which only uses thermoelectric infrared sensors and of which this work continues on. Conclusions regarding what this system is capable of are drawn with its inherent strengths and weaknesses.
267

Observer error in identifying species using indirect signs: analysis of a river otter track survey technique

Evans, Jonah Wy 17 September 2007 (has links)
Indirect signs of species presence (e.g., tracks, scats, hairs) are frequently used to detect target species in occupancy, presence/absence, and other wildlife studies. Indirect signs are often more efficient than direct observation of elusive animals, making such signs well suited for long-term and broad-scale monitoring programs. However, error associated with misidentification of indirect signs can be high, and should be measured if meaningful inferences about population parameters are to be made. This study addressed the need for systematic approaches to estimate and minimize variation due to observer error in identifying indirect signs. I reanalyzed data from 4 replicates of a presence/absence survey of northern river otters (Lontra canadensis) that had been conducted by Texas Parks and Wildlife Department (1996-2003). Sixteen observers had recorded tracks at sample points under bridges (n = 250) distributed throughout 27 counties in the Piney-Woods ecoregion of east Texas. My objectives were to 1) determine if observers were a source of bias in the survey, 2) estimate the proportion of error associated with track identification skill, and 3) evaluate the use of an international certification procedure that measured observer tracking skill. The null hypothesis that observers had no effect on the variation in reported sign was rejected. Indeed, binary logistic regression tests indicated that observers were significantly associated with variation in reported track presence. Observers were not randomly distributed among bridge sites, and therefore were significantly correlated with 4 habitat variables that may have influenced heterogeneity in otter occupancy and probability of detection (watershed, vegetation-type, water-type, bridge-area). On average, experienced observers (n = 7) misidentified 44% of otter tracks, with a range of 0% to 100% correct detection. Also, 13% of the tracks of species determined to be 'otter-like' were misidentified as belonging to an otter. During the certification procedure, participants misidentified the tracks of 12 species as otter. Inaccurate identification of indirect signs is a likely source of error in wildlife studies. I recommend that observer skill in identification of indirect signs be measured in order to detect and control for observer bias in wildlife monitoring.
268

Triangulation Based Fusion of Sonar Data with Application in Mobile Robot Mapping and Localization

Wijk, Olle January 2001 (has links)
No description available.
269

Radar and Thermopile Sensor Fusion for Pedestrian Detection

Rouhani, Shahin January 2005 (has links)
<p>During the last decades, great steps have been taken to decrease passenger fatality in cars. Systems such as ABS and airbags have been developed for this purpose alone. But not much effort has been put into pedestrian safety. In traffic today, pedestrians are one of the most endangered participants and in recent years, there has been an increased demand for pedestrian safety from the European Enhanced Vehicle safety Committee and the European New Car Assessment Programme has thereby developed tests where pedestrian safety is rated. With this, detection of pedestrians has arised as a part in the automotive safety research.</p><p>This thesis provides some of this research available in the area and a brief introduction to some of the sensors readily available. The objective of this work is to detect pedestrians in front of a vehicle by using thermoelectric infrared sensors fused with short range radar sensors and also to minimize any missed detections or false alarms. There has already been extensive work performed with the thermoelectric infrared sensors for this sole purpose and this thesis is based on that work.</p><p>Information is provided about the sensors used and an explanation of how they are set up during this work. Methods used for classifying objects are given and the assumptions made about pedestrians in this system. A basic tracking algorithm is used to track radar detected objects in order to provide the fusion system with better data. The approach chosen for the sensor fusion is a central-level fusion where the probabilities for a pedestrian from the radars and the thermoelectric infrared sensors are combined using Dempster-Shafer Theory and accumulated over time in the Occupancy Grid framework. Theories that are extensively used in this thesis are explained in detail and discussed accordingly in different chapters.</p><p>Finally the experiments undertaken and the results attained from the presented system are shown. A comparison is made with the previous detection system, which only uses thermoelectric infrared sensors and of which this work continues on. Conclusions regarding what this system is capable of are drawn with its inherent strengths and weaknesses.</p>
270

Statistical analysis of weaving before and after managed lane conversion

Araque Rojas, Santiago Andres 20 September 2013 (has links)
This thesis presents a statistical analysis of weaving in a managed lane system which is evolving from a High-Occupancy Vehicle (HOV) system to a High-Occupancy Toll system (HOT). Weaving was, assessed along the I-85 corridor in Atlanta, during three different phases in the conversion from HOV to HOT: 1) the existing HOV managed lane system prior to conversion to HOT lanes, 2) after restriping of some weaving zones but prior to conversion of the HOV lanes to HOT lanes and, 3) after the HOT managed lane system opened. Each phase was analyzed to see how weaving behavior into and out of the managed lane system was affected by changes in the system. To accomplish the analysis, video was collected using Georgia Department of Transportation cameras along the corridor. The videos were transferred to an Android Tablet, in which an App developed by the research team was used to record data from the videos. Using the processed weaving data, a comparison of weaving activity during each phase was performed. Data were also analyzed across time of day, speed differentials, and whether the weaves in question were performed legally (within established weaving zones) or illegally (across double-solid striped lane markings). After a comparison of weaving behavior along different variables, a regression tree analysis was completed. The analysis showed that weaving intensity increased as the system was converted from HOV to HOT. However, illegal weaving decreased significantly once the HOT system was in place, perhaps due to stricter enforcement or perhaps due to driver response to illegally entering and leaving tolled lanes. The regression tree analyses indicated that weaving intensity was highly dependent upon whether it was legal or illegal to weave and upon the phase of conversion during which the weave occurred.

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