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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.
111

3D Near Isotropic Antenna in Package for IoT Applications

Su, Zhen 11 1900 (has links)
Internet of Things (IoT) is an emerging paradigm about building a massive internet to link billions of non-living things to make smart decisions for humans and improve their quality of life. For many of IoT devices, such as wireless sensor nodes dispersed in the environment, there is not much control over their placements or orientations. Thus, there is a need to develop orientation insensitive antennas that ensure reliable data transmission irrespective of devices’ positions or orientations. As billions of such IoT devices required in the future, a low-cost fabrication process suitable for mass manufacturing must be adapted. Antenna in package (AiP) concept is beneficial that the package is utilized to realize the antennas, not only saving space but also reducing the overall cost. For orientation insensitivity, antennas must be near isotropic and even have to maintain their radiation pattern for multi-bands or wide bandwidths in most applications. However, there is a dearth in the literature about design methodologies for near isotropic antennas, particularly for multi-bands near isotropic AiP designs. In addition, a near isotropic behavior is also important for polarization, particularly for CP antennas. To have simultaneous isotropy in radiation pattern and circular polarization is challenging. In the nut shell, this thesis presents theoretical models and derives conditions for wire AiP design for different specifications, single-band and dual-band near isotropic antennas, null free near isotropic antenna with wide CP coverage, and a full CP antenna with decent near isotropy (with very narrow null beam). The single-band AiP has only 5.05 dB gain variation at WiFi/BLE band and the dual-band AiP has a decent near isotropic radiation property and covers both GSM900 and GSM1800 bands. The theoretical model for null-free near isotropic antenna with wide CP coverage is presented with particle swarm optimization (PSO). The full CP antenna has a measured CP coverage of 70% with a small null in the radiation pattern. The results are promising and indicate that the conditions and methods proposed are useful for the future near isotropic AiP design. Also, this work provides designers flexibility to adjust the AiP design according to their own applications.
112

Nativní podpora DEB balíčků pro Spacewalk / Native Support for DEB Packages in Spacewalk

Ďurfina, Lukáš January 2010 (has links)
The system Spacewalk is a managment tool for the linux operating systems based on RPM package manager. The aim of thesis is adding support to Spacewalk for DEB package managment system, which is connected with Debian, a distribution of linux operating system. The result is native support of managing Debian system by the Spacewalk, what includes a registration of system, distribution of configuration files, remote scripts running and managment of DEB packages.
113

Measurement and Analysis of the Physical and Climatic Distribution Environment for Air Package Shipment

Guadagnini, David 01 June 2017 (has links)
The modern air parcel distribution industry has significantly grown to become one of the most commonly employed methods to quickly transport goods throughout the world. Although it comes with many benefits, including higher speed, greater reliability, and tighter security, the multimodal transport system within it can expose packages to a wide variety of climatic and physical distribution hazards. In a single route of transportation, packages could be included in different types of small delivery vans, large commercial semi trucks, cargo dollies, feeder aircraft, and high altitude commercial jetliners. The varying hazard level presented during distribution could directly weaken the packaging components and/or cause product damage. For this reason, it is of utmost importance to properly account for them during package design. Although there have been many past studies to quantify the hazards experienced in specific modes of transport, an over-arching profile of entire distribution route has not yet been developed. Furthermore, after a review of the current testing standards presented in the Code of Federal Regulations as outlined in 49 CFR Part 178, Subpart M, it can be found that many of these currently used testing profiles are not truly representative of the conditions experienced in actual distribution. This study quantifies each hazard element experienced within the modern air parcel distribution environment and develops single testing profiles to accurately represent them. In order to develop single testing profiles for each hazard element, instrumented test packages were sent to multiple domestic and international destinations. Throughout each of these distribution routes, data was collected on the hazard levels experienced. Afterwards, by identifying the amount of time a package spends within each mode of transport, correctly weighted testing profiles were developed. These newly developed profiles represent the minimum hazard level to be included in package performance testing that represents the normal conditions of the air transport environment. Although these composite testing profiles are developed, it is the responsibility of testing laboratories to integrate these updated profiles into their practice.
114

An Investigation of BGA Electronic Packaging Moiré Interferometry

Rivers, Norman 21 March 2003 (has links)
As technology progresses towards smaller electronic packages, thermo-mechanical considerations pose a challenge to package designers. One area of difficulty is the ability to predict the fatigue life of the solder connections. To do this one must be able to accurately model the thermo-mechanical performance of the electronic package. As the solder ball size decreases, it becomes difficult to determine the performance of the package with traditional methods such as the use of strain gages. This is due to the fact that strain gages become limited in size and resolution and lack the ability to measure discreet strain fields as the solder ball size decreases. A solution to the limitations exhibited in strain gages is the use of Moiré interferometry. Moiré interferometry utilizes optical interferometry to measure small, in-plane relative displacements and strains with high sensitivity. Moiré interferometry is a full field technique over the application area, whereas a strain gage gives an average strain for the area encompassed by the gage. This ability to measure full field strains is useful in the analysis of electronic package interconnections; especially when used to measure strains in the solder ball corners, where failure is known to originate. While the improved resolution of the data yielded by the method of Moiré interferometry results in the ability to develop more accurate models, that is not to say the process is simple and without difficulties of it's own. Moiré interferometry is inherently susceptible to error due to experimental and environmental effects; therefore, it is vital to generate a reliable experimental procedure that provides repeatable results. This was achieved in this study by emulating and modifying established procedures to meet our specific application. The developed procedure includes the preparation of the specimen, the replication and transfer of the grids, the use of the PEMI, interpretation of results, and validation of data by finite element analysis using ANSYS software. The data obtained maintained uniformity to the extent required by the scope of this study, and potential sources of error have been identified and should be the subject of further research.
115

Bayesian design and analysis of cluster randomized trials

Xiao, Shan 07 August 2017 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Cluster randomization is frequently used in clinical trials for convenience of inter ventional implementation and for reducing the risk of contamination. The opera tional convenience of cluster randomized trials, however, is gained at the expense of reduced analytical power. Compared to individually randomized studies, cluster randomized trials often have a much-reduced power. In this dissertation, I consider ways of enhancing analytical power with historical trial data. Specifically, I introduce a hierarchical Bayesian model that is designed to incorporate available information from previous trials of the same or similar interventions. Operationally, the amount of information gained from the previous trials is determined by a Kullback-Leibler divergence measure that quantifies the similarity, or lack thereof, between the histor ical and current trial data. More weight is given to the historical data if they more closely resemble the current trial data. Along this line, I examine the Type I error rates and analytical power associated with the proposed method, in comparison with the existing methods without utilizing the ancillary historical information. Similarly, to design a cluster randomized trial, one could estimate the power by simulating trial data and comparing them with the historical data from the published studies. Data analytical and power simulation methods are developed for more general situations of cluster randomized trials, with multiple arms and multiple types of data following the exponential family of distributions. An R package is developed for practical use of the methods in data analysis and trial design.
116

Individualizace / Individualization

Kiriakovský, Šimon January 2018 (has links)
Testing alternative forms of packaging design and also production of promotional materials. Production of package according to production program of Tambor brewery.
117

The Design and Testing of a Waterwaste Treatment Process suitable for Arctic Application

Bromley, David E.G. 10 1900 (has links)
The purpose of the project was to design and test the components of a potential package sewage treatment plant suitable for the Arctic environment. The designed treatment plant was simplistic in concept while utilizing the advantages of both biological and physical-chemical treatment. The system was tested over a ten-week period. The emphasis of the testing was on treatment of high-strength wastes. In addition the effects of temperatures and system start-up-shutdown conditions were assessed. The results indicated that the system operated well under most of the conditions tested. Both the physical-chemical and biological processes complemented each other with the former providing the necessary treatment at start-up and the latter providing low cost treatment once the system had been in. operation for a month. With the high degree of treatment performance achieved, it was felt the process was feasible for Arctic application. However, further testing was recommended to develop the complete package unit. / Thesis / Master of Engineering (ME)
118

Evaluation of Package Delivery Truck Drivers: Task Analysis and Development/Validation of an Objective Visual Behavior Measure to Assess Performance

Grove, Kevin 08 July 2008 (has links)
The job of a package delivery driver (PDD) is complex and demanding. These drivers must possess many skills in order to succeed in their work, including physical stamina, appropriate decision-making, positive customer interaction, and most importantly, operational safety. Companies must use significant resources, not only to provide insurance for existing drivers, but also to train new drivers to use their visual attention effectively while driving, and companies have a vested interest in ensuring that the most capable trainees are selected for jobs. Currently, subjective assessments of supervisors or managers are typically used to make these determinations. While these are valuable methods for assessing drivers, an objective measure of how well the driver is using his/her visual attention would both assist evaluators in making judgments, as well as make those judgments more accurate. The purpose of the study described herein was to 1) conduct a task analysis of the driving component of the PDD job responsibilities, and 2) create and test an objective measure that a package delivery company could use to evaluate the performance of its drivers. A detailed task analysis based on numerous observations of drivers in their normal work routines was conducted for this research in order to understand these complex tasks. A framework was created for understanding this system of tasks, which was then used to organize all tasks that drivers were observed to perform into more general, goal-oriented activities. Using this task analysis, incidents were identified that were observed while drivers were behind the wheel. This information demonstrated that breakdowns were occurring within the tasks drivers were performing and that improved methods of training and evaluations may be needed as a result. A construct of visual behavior called Head Down Time (HTD) was then created and tested. An individual HDT is defined as the sum of time of all eye gazes away from the primary display (i.e. windshield) between two distinct eye gazes at the primary display while the vehicle is in motion. HDT was evaluated for its ability to differentiate levels of experience between drivers, its relationship to types of route on which drivers delivered, and its relationship to the driving-related incidents that were observed. HDTs were shown to be differed significantly between drivers of low and high experience, with experienced drivers displaying shorter durations of HDT when compared to inexperienced drivers. HDTs also differed in duration when analyzed by the type of route upon which drivers operated. Commercial and urban routes, while not significantly different with respect to HDT, were shown to have increased HDT durations when compared to rural routes and, in turn, residential routes were found to have significantly longer HDTs than did rural routes and may have significantly shorter durations compared to commercial and urban. Finally, HDTs that were associated with observed driving incidents in terms of chronological proximity were shown to be of significantly longer duration than were HDTs that were not associated with incidents. All tests were conducted using appropriate statistical measures, including t-tests at a level of α = 0.05 for each dataset. Applications of this research include: 1) improvement of PDD training and evaluation methods through use of a detailed task analysis, 2) improvement in how package delivery companies define incidents and train PDD toward the prevention of incidents based on task analysis and observations as to incident frequency, and 3) the further development of HDT as a possible objective measure to supplement the training and evaluation of PDD. / Master of Science
119

Development of a User Oriented Optimization System For Computer Aided Design Packages.

Jha, Virendra Kumar 02 1900 (has links)
A new user oriented optimization system is described which is particularly useful for integration into user oriented design packages. Four new subroutines have been developed for the system, one being for integer or mixed integer nonlinear problems. A description is given of the problem of handling constraints while solving optimization problems. The technique of integration into a design package is discussed. Solutions of four sample problems have been included to demonstrate use of the subroutines. / Thesis / Master of Engineering (ME)
120

The Design and Implementation of the Test Package for the Serial Output Controller board

Karapetsas, Spyridon 12 1900 (has links)
<p> The Serial Output Controller is one of the component boards of a Marine Navigation System. Litton Systems (Canada) Limited required the development of a test package for this board to be implemented on the DIGIPACT test station. This report introduc.es the subject of electronic component board testing with an overview of the test equipment and underlying philosophies used by Litton Systems for fault detection and fault diagnosis. The four stages of the test package development process, test plan definition, programming, validation and evaluation are described. The architecture of the DIGIPACT test system is presented as background information. </p> / Thesis / Master of Engineering (MEngr)

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