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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.
21

A pragmatic approach to the functional analysis of chipped stone tools

Finlayson, Bill January 1990 (has links)
No description available.
22

PresenteraMera : En rapport om skapandet av ett interaktiv presentationsverktyg / PresnteraMera : A document about the creation of an interaktive salespresentation-tool.

Birgisdottir, Hrefna January 2012 (has links)
This report describes the background, approach, and the final results for the presentation tool PresenteraMera. PresenteraMera is an online-based, interactive presentation tool that is created to improve the quality of sales presentations and simplify the creation of presentations. The client for this project is Dempsey, a digital advertising agency and production company with headquarters in Stockholm. PresenteraMera consists of several features that make it easier for businesses to create, edit and display their presentations. The tool also allows the user to always be sure that the presentations created with PresenteraMera follows a specific design, based on their graphic manual for example.
23

Building in Puma

Ho, Rosanna January 2010 (has links)
It is proven that sustainable development only occurs when ideas and resources are locally adapted; however, many conventional development approaches ignore local voices and treat them merely as passive consumers. Today, communication networks and technologies are decentralizing information. Citizens are empowered with unprecedented access to ideas, resources, and tools with which they may execute initiatives on their own terms. It is imperative that designers interested in working with the Global South face the implications of this contemporary terrain of interconnectivity: with new platforms for empowered community-led production, we must re-imagine our role as collaborative partners in development. The thesis focuses on a previously isolated and underdeveloped village in central Tanzania called Puma. Newfound connectivity has provided them with valuable access to development resources, but also has overwhelmed them with its scope and capacity, placing them in sudden proximity to varied and unfamiliar communities. In this terrain where tradition must confront the foreign, the thesis proposes an intervention that will foster communication across lines of difference and stimulate a process of reciprocal learning to generate development initiatives specific to Puma’s needs. This thesis identifies how an outsider architect can insert herself into Puma and forge a relationship that can effectively make use of the local-global collaborative potential. The thesis proposes an architectural intervention to help foster a dialogue on this subject. Using a building form and the building process, architecture will act as a dialogic tool for the navigation and confrontation of the unfamiliar and the cultivation of an enduring local-global partnership.
24

Reliability test of a RIFD system for tool management on construction sites

Kalla, Naresh 15 May 2009 (has links)
In the construction industry, one of the aspects that affect the productivity of the construction crew is the availability of tools and supplies. Unavailability of tools and supplies results in a delay of the project, which in turn increases the cost of the project. If any such delays on job sites could be reduced, it would help the construction industry in reduction of time and cost losses. The construction industry is in need of a technology that would improve the presentday tool management system (TMS) to reduce the construction costs from delays in projects. Radio Frequency Identification (RFID) technology offers the possibility that tools and supplies, tagged with RFID devices, could be tracked down automatically. Although the potential of RFID is real, it does have limitations like any other technology. Without understanding and working with the limitations of RFID, this technology may disappoint many before its true and significant capabilities are realized. Before the technology is executed fullfledged, it needs to be tested for reliability on construction sites in particular. Researchers, from many parts of the world, have performed tests to understand the reliability of the RFID technology considering variables like metal interferences, reading range, multiple tag identification, etc. But these tests conducted could not discuss all the factors that may affect the reliability of the technology. This paper identifies other factors that might affect the reliability of RFID technology and tests are conducted to understand the influence of these factors on the readability of the RFID tags. Number of tools and the velocity with which tools are taken across the portal are two variables that are tested for reliability of RFID. Tests are conducted using the experiment setup that resembles a construction site tool management room entrance/exit. Results show a radical decrease in the readability of tags, while the numbers of the tools are increased gradually. And also, when the tools were taken across the RFID portal with gradual increasing velocity, the readability reduced. These results prove that both the tested parameters have an effect on the reliability of RFID technology for tool tracking.
25

Adhesion effect on tool wear of polishing process

Ou, Chia-ching 14 July 2004 (has links)
The adhesive effects between abrasive particle and work on tool wear of the polishing process were considered in the study. Adhesive strength of the interfaces may affect wear rates of tool on the different adhesive way. Several sets of experiments were designed to reveal some phenomena about the wear rates of tool and work. There are variations in the adhesive of the interface causing different degree of tool wear for distinct kind of abrasive particle¡Bwork and tool¡¦s material. The experimental study demonstrated that the wear rate of tool was related to the adhesive strength between abrasive particle and work. Any change of the adhesive strength may significantly alter the wear rate of tool. An analytical study was done to examine the role played by the adhesive strength at the interfaces of abrasive particle on the wear rates of tool and work. It was derived from the law of force equilibrium and the principle of minimum potential energy. Tool wear was affected for polishing process by altering adhesive strength. The computer simulations indicated that an enhancement of adhesion between abrasive particle and work would always increase the wear rate at tool while the wear rate of work could be increased or decreased. To prove analytical study was reasonable by experimental study. Finally,the possible causes of observed phenomena and the limitations of the study were discussed.
26

The Implementation of an Authoring Tool for e-Learning Platform

Chen, Chih-Chia 30 August 2004 (has links)
On e-Learning platform, it used to make use of teaching materials with static media (Html, Word, PowerPoint, PDF) traditionally. With Increases in computing power recently, dynamic teaching materials like multi-media have been used progressively on e-Learning platform. Media like audio and video, nevertheless, need more and more computing ability, even employed with the last compression technology (MPEG-4, WMV9, H.264, AAC) to enhance compression ratio. At the same time, they neglect to integrate existing static teaching materials in addition. Hence, ¡§are video media necessary?¡¨ which is a good idea we reflect upon. An authoring tool fit the standard teaching materials bears the characteristics of teaching materials re-use and exchanging. As a result of this, our system integrates each material to transform ones into an appropriate media for a variety of education environments. For instance, compatible with traditional static media, simple films, transforming them into streaming to delivering via networks, even our synchronized learning methods, as can be achieved with demands from students. The synchronizations of materials our system provides can integrate voice and power-point slides into an on-line presentation with the feature of dynamic exposition to impart knowledge to students more effectively. Of course, it also can be played back, recording in real time, and showing presentations in full screen like ordinary PowerPoint. Further, we can do authoring after recorded. In this feature, we can set time stamp on each slide arbitrarily to achieve the best purpose of presentation.
27

A digital tool for sustainable urban planning : A case study of introducing a carpool in a residential area in Uppsala

Lillo, Gustav, Sahlén, Klara, Swenman, Marie January 2015 (has links)
The purpose of this project is to create a simplifiedtool for urban planning, to illustrate how differentparameters affect each other. The municipality ofUppsala and the company Atkins have investigatedthe possibility to implement several themes andaspects in a digital tool. Since urban planning has acomplex structure, only a few aspects are selectedin this report. This is a case study which examineshow an implementation of a carpool in a residentialarea affects the parameters ground use, carbondioxide emissions and social aspects such asridesharing and car ownership. A model has beencreated in MATLAB to visualize the environmentalimpact of a carpool compared to traditional parking.The results show that the environmental impactdecreases as the number of cars in the areadecreases. Further, the sensitivity analysis showsthat social factors may have a great impact on theenvironmental aspects. A decreased car usage andincreased ridesharing, where only traditional parkingis used, can result in an environmental improvementalmost corresponding to an area with only a carpoolsolution with the current car usage and ridesharing.
28

Quality control of a diagnostic tool through qualitative and quantitative measurement assessment of field testing

Jidegren, Martin, Gupta, Tushar January 2015 (has links)
The purpose of this study is to develop a method to qualitatively and quantitatively measure and assess the field testing of a diagnostic tool by identifying the parameters that are relevant to assess a field test. The study is conducted at Scania CV AB, Södertälje, Sweden, a world leading manufacturer of trucks, buses and industrial and marine engines, where a method to assess the field test of their diagnostic currently does not exist. The study follows a deductive approach while taking a positivistic and hermeneutic perspective. The relevant theories and literature such as quality development and software testing are described to give a better understanding of the study. The study is conducted in four main steps- description of present situation, situation analysis, development of the assessment approach or framework and evaluation of the framework. The empirical information gathered from numerous interviews and meetings is presented in the description of present situation along with the various data sources available. The collected data from different databases is analysed where hypotheses are formulated based on the different influencing parameters for field testing. The correlations between the parameters are then calculated and analysed to verify the hypothesis as True or False. The ECU updates are also analysed to show that the ECU updates performed during field testing is a good representation of the actual usage after release. The framework to assess the field test is then developed using the available data and analysis made. A holistic view is taken to include the processes before and after the field test in the framework. The framework is in the form of an Excel workbook where data is either copied from databases or manually entered and relevant graphs describing the field test are generated automatically. The time period to be displayed on the graphs can be selected manually. This gives a good base to take decisions about how a field test has gone and whether or not the software is ready for release. Based on the correlation of the different parameters, a table with different key values of how much field test usage that should be conducted based on the number of implemented change requests are presented. Thus the result is that the most important attributes to consider for a field test are the amount of implemented changes where each field test usage occasion increases the chance of finding potential faults in the software of the diagnostic tool. An unrestricted framework is also described using data that may be available, but currently difficult to utilise effectively. Thus the recommended future work is represented by this framework which describes what information that can be obtained from different data sources and how they can be used to get a detailed understanding of what exactly has been used during field testing as well as after the software has been released. The framework is assessed in the last step and its uses along with limitations are described.  The difficulty in describing the success of software testing is also discussed to give a good context to the framework and understand its utility.
29

Building in Puma

Ho, Rosanna January 2010 (has links)
It is proven that sustainable development only occurs when ideas and resources are locally adapted; however, many conventional development approaches ignore local voices and treat them merely as passive consumers. Today, communication networks and technologies are decentralizing information. Citizens are empowered with unprecedented access to ideas, resources, and tools with which they may execute initiatives on their own terms. It is imperative that designers interested in working with the Global South face the implications of this contemporary terrain of interconnectivity: with new platforms for empowered community-led production, we must re-imagine our role as collaborative partners in development. The thesis focuses on a previously isolated and underdeveloped village in central Tanzania called Puma. Newfound connectivity has provided them with valuable access to development resources, but also has overwhelmed them with its scope and capacity, placing them in sudden proximity to varied and unfamiliar communities. In this terrain where tradition must confront the foreign, the thesis proposes an intervention that will foster communication across lines of difference and stimulate a process of reciprocal learning to generate development initiatives specific to Puma’s needs. This thesis identifies how an outsider architect can insert herself into Puma and forge a relationship that can effectively make use of the local-global collaborative potential. The thesis proposes an architectural intervention to help foster a dialogue on this subject. Using a building form and the building process, architecture will act as a dialogic tool for the navigation and confrontation of the unfamiliar and the cultivation of an enduring local-global partnership.
30

Tool Condition Monitoring and Replacement for Tubesheet Drilling

2013 September 1900 (has links)
Tool Condition Monitoring (TCM) methods have shown significant potential to automatically detect worn tools without intervention in the machining process, thus decreasing machine downtime and improving reliability and part quality. Previous research on TCM systems have used a wide variety of time-domain and frequency-domain features extracted from cutting force related parameters as well as mechanical and acoustical vibrations to infer the wear state of tools. This project concerns the process of drilling thousands of tight-tolerance holes on tubesheets and baffles of heat exchangers using large diameter indexable insert drills on a horizontal boring machine. To address the issues involved in the process, the aim of this research is to develop a non-intrusive, indirect, online TCM system on the horizontal boring machine to monitor the drill wear and hole quality while drilling. The specific objectives are to establish an indirect TCM system for the drilling process, to develop models to predict tool wear and the machining accuracy of the drilled holes, and to develop an optimum tool replacement strategy. The TCM system developed used two cutting-force related signals on the horizontal boring machine, namely the spindle motor current and the axial feed motor current. Features extracted from these data streams, as well as the machining parameters, the cutting speed and the feed rate, and the number of holes drilled with the current inserts, are the inputs to a series of models to predict the tool wear state and the hole diameter. The first model is an autoregressive model that allows the prediction of the extracted features for the next hole before it is drilled. As each hole is drilled, this model is updated with the most recent data to improve the accuracy of the prediction. The predicted values for the features are then used as inputs to the second and third models which are surface response models, one to estimate the tool wear state and one to estimate the hole diameter. A tool replacement strategy based on applying limits to the predicted hole diameter was also developed. Adjusting these limits allows the strategy to be tuned for either hole accuracy or tool life depending on the requirements of a specific application. Tuning the replacement strategy for tool life resulted in a significant 44% increase in tool life and a non-trivial reduction in machine down time due to fewer tool changes while holding a hole diameter tolerance of ±0.1mm. The TCM system ensured that not a single over tolerance hole would have been drilled which is critically important since over tolerance holes can result in a scrapped workpiece. The proposed 3-model TCM system shows promise in being able to significantly reduce the risk of drilling out of tolerance holes while at the same time increasing tool life and correspondingly decreasing tool change time. The models are able to accurately predict the insert flank wear and as well as the actual hole diameter within acceptable error. The TCM system could be implemented in an industrial settingwith minimal revision and since it is an indirect system there would be no intrusion into the manufacturing operation. One limitation of the TCM system as proposed is that it is only capable of detecting gradual tool wear and not catastrophic tool failure, a limitation that was known from the outset but was not investigated as it was beyond the scope of this project. The proposed TCM system would allow the integration of additional functionality to instantaneously detect catastrophic tool failure. Finally, for use in a production environment, the developed models need to be implemented on a standalone device that requires essentially no operator input to monitor continuous drilling operations for tubesheet and baffle applications. This implementation could include automatic detection of the machining parameters using frequency analysis of the motor signals.

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