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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

Lowest Cost Alternative to Auto-Tracking Using GPS-TRAK, Augustin-Sullivan Distribution, & Single Axis Antenna Techniques

Augustin, Eugene P., Dunn, Daniel S., Sullivan, Arthur 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The first telemetry tracking system was desired in 1959 for the space program. Cost was of little concern. The tracking technique used was 3 channel monopulse which is still today, after all these years, the optimum in performance for any type of tracking requirement. Telemetry tracking really got off the ground in the early 1970's with the move from P-Band to S-Band for telemetry. In the design of early tracking systems, performance was on the top of the list, and cost was on the bottom of the list in establishing the design criteria. By the beginning of the 1980's cost was approaching performance in importance. Today, with the demise of the cold war and a considerable reduction in global threats coupled with the state of the world economy, cost has now reached the top of the list. The cost of a telemetry tracking system can be reduced by more than a factor of two by going to a single axis tracking technique. The lowest cost single axis approach heretofore has been the use of a cosecant squared (CSC²) distribution. To improve the efficiency of a single axis system and increase the overhead coverage capability, the use of a dual beam antenna has been widely used as another type of single axis approach. The dual beam technique involves additional costs since two tracking antennas are required. Except for satellite tracking, almost all telemetry tracking is performed at low elevation angles and, like it or not, multipath is there. The multipath fade varies from a few dB, to over 20 dB depending upon the reflecting terrain. Most general purpose systems should be designed for at least a 10 dB multipath fade. For all telemetry tracking applications, the multipath effect is completely negligible at elevation angles greater than 10 degrees. The Augustin-Sullivan Distribution, in effect, fades away the multipath margin as the multipath effect decreases. Because of the multipath phenomenon, an antenna beam should not be shaped at the one dB point as is the case with a CSC² distribution, but only needs to be shaped from somewhere between the 15 - 20 dB level based on the mission requirements. This involves a gain reduction from a pencil beam on the order of 1/2 dB or less, rather than the 3 dB reduction associated with the CSC² distribution. The Augustin-Sullivan distribution does not start shaping the beam until shaping is retired, and shapes the beam for constant altitude coverage from the horizon to zenith. For the first time, coverage is provided from the peak of the beam to directly overhead with a single antenna and a single axis rotator. When GPS information is available from the tracked vehicle, the Augustin-Sullivan distribution, with a single axis rotator and using the GPS-TRAK technique, results in the lowest possible cost alternate to autotracking.
2

Global Positioning System Analysis of a High School Football Scrimmage

Gleason, Benjamin H., Sams, Matthew L., Salley, John T., Pustina, A. Andrew, Stone, Michael H. 01 August 2017 (has links)
The purpose of this study was to examine the physical demands of a high school American football scrimmage. Male high school football players (N = 25) participated in a spring scrimmage. Global positioning system data and game film were recorded throughout the entirety of the scrimmage to determine the total distance covered, the distance covered in different velocity bands, the number of accelerations and decelerations performed, and the work-to-rest ratio of the scrimmage. The athletes were divided into 2 groups: linemen (L) (N = 7) vs. nonlinemen (NL) (N = 8) for statistical analysis, and independent T-tests with Holm's sequential Bonferroni adjustment were used to determine differences in movement characteristics between the L and NL groups. Average play duration was 5.7 ± 2.1 seconds, whereas the rest interval was 33.4 ± 13.6 seconds between plays, for an overall exercise-to-rest ratio of 1:5.9. Total distance, standing and walking distance, running distance, striding distance, sprinting distance, and total high-speed running distance covered by NL was greater than L (statistically significant at p ≤ 0.05). Distances traveled in each velocity band by position and by play are also included to provide context of our findings. Data from the present study add to the pool of support for the use of position-specific training in preparing high school football players for competition.
3

Robustness in constructing a network of induced emissions based on GPS-tracking data

Al-Soloh, Mohanad, Al-Isawi, Arkan January 2017 (has links)
The mobility of people, freight and information is fundamental to economic and social activities such as commuting, manufacturing, distributing consumer goods and supplying energy. There are two major problems that arise as a result of mobility. The first is economic cost and the second is environmental impact which is of increasing concern in sustainable development due to emission levels, particularly as a result of car use. This study focuses on constructing a network of induced emissions (NOIEs) by using three models and checking the robustness of NOIEs under varying parameters and models. The three models are Stead’s model, the NAEI model, and Oguchi’s model. This study uses the Swedish city of Borlänge as the case study. Calculating CO2 emissions by constructing the NOIEs using Stead’s model appears to give an underestimation when compared to results from a NOIEs which applies Oguchi’s model. Results when applying the NAEI model in constructing a NOIEs also give an underestimation compared to a NOIEs applying Oguchi’s model. Applying the NAEI model is, however, more accurate than applying Stead’s model in constructing a NOIEs. The outcomes of this study show that constructing a NOIEs is robust using Oguchi’s model. This model is preferable since it takes into account more important variables such as driving behavior and the length of the road segments which have a significant impact when estimating CO2 emissions.
4

Grundläggande undersökning och utveckling av GPS- spårningssystem för androidenheter / Basic Analysis and Development of GPS-Trackingsystem for Android

Strömberg, Niclas January 2015 (has links)
Denna rapport redogör dels för utvecklingen av två applikationer för Android och dels för jämförelsen mellan de två. Dessa applikationer skulle regelbundet samla in och skicka sin position till en server för spårning. Tanken var att en administratör för till exempel ett orienteringsevent skulle kunna följa deltagarna i realtid. I slutet av rapporten återfinns en utvärdering av de två applikationerna som utvecklades som försöker avgöra vilken av de två applikationerna som verkar effektivast med avseende på energikonsumtion och dataöverföringshastighet.   Arbetet utfördes åt Progmera i Linköping som tidigare haft en del kunder inom bl a orienteringsbranchen. / This report details both the development of two separate applications for Android and a comparative evaluation between the two. The applications where supposed to regularly collect and transmit the device position to a server for tracking. The applications where meant to be used at orientation events to maintain locations of all participants in real-time. At the end of this report the evaluation tries to determine the most effective solution based on energy consumption and data transfer time.   The project was performed for Progmera in Linköping, Sweden. The company had clients in the orientation business.
5

The Influence of Diet and Foraging Behavior on Carotenoid Ornaments in the Brown Booby (<i>Sula leucogaster</i>)

Michael, Nathan January 2020 (has links)
No description available.
6

The use of time study, method study and GPS tracking in improving operational harvest planning in terms of system productivity and costs

Odhiambo, Benedict O. 12 1900 (has links)
Thesis (MScFor (Dept. of Forest and Wood Science)--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: This study aims to quantify the benefits of implementing an operational harvesting plan in forest harvesting operations. This is to be achieved by comparing productivity and costs from unplanned and planned harvesting operations. The study was conducted on a Pinus radiata plantation owned by Mountain to Ocean Forestry Company (Pty) Ltd (MTO) located near the town of Grabouw in the Western Cape Province of South Africa. MTO conducts harvesting operations using semi-mechanised tree-length harvesting systems. A wheeled H67 Clark Ranger cable skidder is used to extract tree-lengths from infield to the landing. Data was obtained both manually (work study) and from GPS tracking. Choking and dechoking data was obtained through time and method studies. GPS tracking was used to measure travel loaded and travel empty times, as well as travel distances and travel speeds. The aim of using both manual techniques and GPS tracking was to obtain detailed and spatially accurate information about the operation. The operating costs were estimated using South African Harvesting and Transport Costing Model. Productivity of the newly introduced tagline system (45.97 m³/pmh) exceeded that of mainline system (37.85 m³/pmhh) by 26%. The unit production cost of using tagline system (R20.21/m³) was 10% lower than the unit production cost of using mainline system (R22.54/³3). There were no benefits to be gained from improving the level of skid trail construction by removal of logging residue or cutting down stumps to as near the ground level as possible. A combination of manual (time and method studies) data collection and GPS tracking provided more detailed and accurate information on the semi-mechanised harvesting system. / AFRKAANSE OPSOMMING: Hierdie studie beoog om die voordele van die uitvoering van 'n operasionele inoestingsplan te kwantifiseer. Dit word bereik deur produktiwiteit en kostes van beplande en onbeplande inoestingswerksaamhede te vergelyk. Die studie is gedoen in Pinus radiata opstande van Mountain to Ocean Forestry Company (Pty) Ltd (MTO) naby Grabouw in die Wes-Kaap provinsie van Suid Afrika. MTO gebruik semi-gemeganiseerde boomlengte inoestingstelsels in hul inoestingswerksaamhede. . H67 Clark Ranger wielsleeptrekker met kabel en wenas is gebruik om boomlengtes van die veld na die pad te sleep. Data is versamel deur van beide hand (werkstudie) en GPS-opsporing gebruik te maak. Afhaak en aanhaak data is verkry deur van tyd- en metodestudies gebruik te maak. Gelaaide en ongelaaide tyd, spoed en afstande is met behulp van die GPS gemeet. Deur van beide hand en GPS versamelingsmetodes gebruik te maak, kon omvattende sowel as ruimtelik akkurate inligting oor die werksaamhede verkry word. Die bedryfskostes is verkry van die South African Harvesting and Transport Costing Model. Produktiwiteit van die nuut ingestelde verbindingslynstelsel (45.97 m³/pmh) het die hooflynstelsel (37.85 m³/pmh) met 26% oorskry. Die eenheidsproduksiekoste van die verbindingslynstelsel (R20.21/m³) was 10% laer as die eenheidsproduksiekoste van die hooflynstelsel (R22.54/m³). Daar was geen voordeel in die verbetering van die sleeppad konstruksie deur afval te verwyder of stompe nader aan die grondvlak af te sny nie. 'n Kombinasie van hand (tyd- en metodestudies) dataversameling en GPS-opsporing het meer akkurate en omvattende inligting oor die semi-gemeganiseerde inoestingstelsel verskaf.
7

Real-time Wind Direction Filtering for Sailboat Race Tracking

Nielsen, Emil January 2015 (has links)
In this paper, an algorithm that calculates the direction of the wind from the directions of sailors during fleet races is proposed. The algorithm is based on a 1-D spatial convolution and it is named Convolution Based Direction Filtering (CBDF). The CBDF-algorithm is used in the TracTrac race client that broadcasts sailboat races in real-time. The fact that the proposed algorithm is polynomial makes it suitable, to be used as a real-time application inside TracTrac, even for large fleets. More concretely, we show that the time complexity of the CBDF-algorithm is O(n2), in the worst-case, where n &gt; 0 is the number of boats in competition. It is also shown that in more realistic sailing scenarios, the CBDF-algorithm is in fact a linear algorithm.
8

Feasibility of digital contact tracing in low‑income settings – pilot trial for a location‑based DCT app

Handmann, Eric 18 April 2024 (has links)
Abstract Background Data about the effectiveness of digital contact tracing are based on studies conducted in countries with predominantly high- or middle-income settings. Up to now, little research is done to identify specific problems for the implementation of such technique in low-income countries. Methods A Bluetooth-assisted GPS location-based digital contact tracing (DCT) app was tested by 141 participants during 14 days in a hospital in Monrovia, Liberia in February 2020. The DCT app was compared to a paper-based reference system. Hits between participants and 10 designated infected participants were recorded simultaneously by both methods. Additional data about GPS and Bluetooth adherence were gathered and surveys to estimate battery consumption and app adherence were conducted. DCT apps accuracy was evaluated in different settings. Results GPS coordinates from 101/141 (71.6%) participants were received. The number of hours recorded by the participants during the study period, true Hours Recorded (tHR), was 496.3 h (1.1% of maximum Hours recordable) during the study period. With the paper-based method 1075 hits and with the DCT app five hits of designated infected participants with other participants have been listed. Differences between true and maximum recording times were due to failed permission settings (45%), data transmission issues (11.3%), of the participants 10.1% switched off GPS and 32.5% experienced other technical or compliance problems. In buildings, use of Bluetooth increased the accuracy of the DCT app (GPS + BT 22.9 m ± 21.6 SD vs. GPS 60.9 m ± 34.7 SD; p = 0.004). GPS accuracy in public transportation was 10.3 m ± 10.05 SD with a significant (p = 0.007) correlation between precision and phone brand. GPS resolution outdoors was 10.4 m ± 4.2 SD. Conclusion In our study several limitations of the DCT together with the impairment of GPS accuracy in urban settings impede the solely use of a DCT app. It could be feasible as a supplement to traditional manual contact tracing. DKRS, DRKS0 00293 27. Registered 20 June 2020 - Retrospectively registered.
9

Ett gränssnitt för en lättare användning : En kvalitativ studie om en mobilspårningsapplikations gränssnitt och vilka element som behöver utvecklas / An interface for easier use : A qualitative study of a mobile tracking application's interface and the elements that need to be developed

Olin, Joakim, Wahlgren, Bryan January 2022 (has links)
I takt med att ägandet av smartphones ökat samt att tekniken utvecklats så har det blivit allt mer förekommande med spårning av GPS-enheter. Användningen innefattar flera områden som exempelvis berör spårning av djur, fordon och människor. Tidigare forskning har främst fokuserat på de tekniska aspekterna med GPS och i flera av dessa källor nämns kortfattat att de mobila gränssnitten har fått kritik från studiernas deltagare och ansetts vara svåra att använda. Syftet med studien var att öka förståelsen för hur spårningsapplikationers gränssnitt kan utformas för att bli mer användarvänliga. Att genom ett användarcentrerat arbete kartlägga vilka element i nuvarande gränssnitt som kan förbättras för att underlätta användares kognitiva belastning vid användning. Studien hade en kvalitativ ansats och data samlades in genom intervjuer med erfarna användare av spårningsapplikationen Go. Det var Go-applikationens gränssnitt som undersöktes i studien. För att kunna besvara forskningsfrågan användes Foggs beteendemodell, UX och informationsarkitektur för att skapa intervjufrågor samt för att analysera och diskutera resultaten. Studiens resultat är inte generaliserbart eftersom urvalet var för litet och ej slumpmässigt framtaget. Därmed gav studiens resultat endast en första inblick av vilka element i gränssnittet som var i behov av att utvecklas för att förbättra spårningsapplikationens gränssnitt. Studien visade att informanterna var tillräckligt motiverade och att det framför allt var förmågan som behövde ökas och att det i vissa fall behövdes triggers. De element i gränssnittet som behövde utvecklas var historiken, larm, platsmarkörer, inställningar, informationssidan och livespårning. Tillvägagångssätten för att utveckla dessa element berör oftast ett grafiskt tydliggörande eller förklarande. / As the usage of smartphones has increased and the technology also has developed, it has become increasingly common with tracking of GPS devices. The usage includes multiple areas such as tracking of animals, vehicles, and people. Early research has mainly focused on the technical aspects with GPS and in a few of these sources it is briefly mentioned that mobile interfaces have been criticized by the study participants and are considered difficult to use. The purpose of this research was to increase the understanding on how tracking applications interface can be designed to be more user friendly. Through a User-Centered work to map how elements and functions in a current interface can improve to ease the users cognitive load during usage. The research had a qualitative approach and the data that was collected through interviews with experienced users of the tracking application Go. It was the interface of Go that was being studied during the research. To answer our research question, Fogg's behavior model was used together with UX and information architecture to create questions for the interviews and to analyze the results. Results of this research are not generalizable since the sample was small and not randomly selected. Hence, the results of the research provided a first insight of which elements in the interface that need development to improve the interface of tracking applications. The research showed that the informants are motivated enough and that it was primarily their ability that needed to be increased and, in some cases, triggers were needed. The elements on the interface that needed to be developed were, the history, the alarm, placemarks, settings, information page and live tracking. The approach to develop the elements often touches on a graphical clarity or explanatory note.
10

Dockningsstation

Söderman, Hampus, Erik, Hedin January 2016 (has links)
Denna rapport behandlar arbetet med att ta fram en ny produkt med ändamålet att underlätta för jägare som jagar med hund. I ungefär tio år har så kallade GPS-pejlar använts av jägare. Hunden utrustas med ett sändarhalsband och hundföraren tar med sig en handenhet på vilken denne kan se vart hunden befinner sig. Genom en undersökning riktad mot hundförare som görs i projektets startskede klargörs dock ett behov av ett nytt sätt att bära handenheten vid jakt, någon typ av dockningsstation. Något som tillåter hundföraren att kunna utnyttja pejlens praktiska funktioner och fortfarande ha båda händer fria till att exempelvis hålla i sitt vapen eller klättra i branta sluttningar. En målsättning skapas för projektet, att ta fram ett produktkoncept vilket utgör en dockningsstation för en pejl av modellen Astro 320 från tillverkaren Garmin. Produkten skall vara tillförlitlig i fält, tillåta hundföraren att i alla lägen ha båda händer tillgängliga och inte begränsa varken rörlighet eller skytte. Utifrån den undersökning som görs skapas även en kravspecifikation vilken används som riktlinje i arbetet med dockningsstationen. I projektets slutskede genereras ett koncept bestående av tre delsystem, ett enhetsfäste vilket fäster i handenheten, ett armfäste vilket sitter som ett armband runt hundförarens underarm samt en länk vilken kopplar samman de två övriga delsystemen. Länken består av två separata delar vilka enkelt kan docka stabilt i varandra och lika enkelt tas isär och erbjuder hundföraren val av vart denne vill bära handenheten samt vilken vinkel handenheten har gentemot underarmen. Armfästet är utrustat med ett särskilt designat klickspänne vilket genom två lägen både erbjuder stabil fastspänning av dockningsstationen och snabb justeringsmöjlighet av handenhetens placering på underarmen. En fysisk funktionsprototyp tillverkas för att utföra tester på och utvärdera resultatet av projektet. Efter tester kan det konstateras att samtliga krav i kravspecifikationen uppfyllts, att projektets målsättning har nåtts och att konceptet anses ha god potential för vidareutveckling till en färdig välfungerande produkt. / This report reviews the process of designing a new product with the purpose of aiding hunters using dogs. Since approximately 10 years GPS tacking devices have been used by hunters using dogs. The dog is equipped with a transmitting collar and the hunter brings a hand held receiver unit. The hunter can keep track of the dog’s current position through the handheld units display. But through a survey targeted at hunters, which is done in the first phase of the project, a desire for a new method of carrying the unit, some sort of docking system, is made clear. A device which would allow the user to utilize the handheld unites practical features while retaining full capability to use both hands to hold their weapon or climb steep slopes. An objective for the project is formed, to design a product concept for a docking station made to fit the product Garmin Astro 320. The docking station should be reliable during hunting, allow the user to always retain the possibility of using both hands and it shouldn’t decrease neither movement nor the ability to shoot. Based on the survey a list of requirements is made which acts as guidelines during the design process. In the later phases of the project a product concept is designed consisting of three subsystems, a unit attachment which attaches to the handheld unit, an arm attachment which mounts the users forearm and a link connecting the other subsystems. The link consists of two separate parts that easily dock with each other and as easily are separated allowing the user to choose where to carry the unit and at what angle it sits on the forearm. The arm attachment is equipped with a specially designed clip buckle with two modes, offering both a stabile attachment to the arm and the possibility to quickly adjust the attachments positioning around the forearm. A physical prototype is made for testing in order to evaluate the projects results. After completed tests the results establish that all the requirements have been met, the project obtained its objective and the product concept has a lot of potential to further develop into a functioning product.

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