• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 109
  • 80
  • 39
  • 13
  • 10
  • 6
  • 3
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 298
  • 52
  • 34
  • 34
  • 33
  • 29
  • 29
  • 29
  • 27
  • 26
  • 25
  • 25
  • 23
  • 23
  • 23
  • 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.
291

Komunikační zařízení přes GSM/GPRS / Communication devices over GSM/GPRS

Prečan, David January 2010 (has links)
This master thesis deals with a data remote transmission by means of SMS and GPRS technology. The overview of current solutions is presented and then a remote temperature measurement and a data transmission employing a communication module GSM/GPRS TM1 through GSM network using GPRS technology is described. As a response to an impulse, the communication module sends SMS. The technical solution is described in details including HW and SW design of the data transfer and processing equipment using a ATmega 162 microprocessor. This equipment communicates with a server (PC), which displays the measured temperature. A prototype which was used for a validation of the design is also described.
292

Návrh automatizovaného měřicího pracoviště s průmyslovým robotem / Design of measurement robotized workcell

Tvardek, Michal January 2013 (has links)
This master's thesis focuses on the use of the Renishaw's Equator gauging system in cooperation with the industrial robot. The target is to design the robotized workcell which contains these two products. Robot acts as a manipulator for inserting and sorting out the workpieces into the "good" and "bad" pallets according to measured results from the Equator. Equator uses a parallel kinematics and probing system which is normally used on coordinate measuring machines. Therefore there is the introduction to the parallel and serial kinematic structures, to the problems of the coordinate measuring machines in the first part of this thesis. It was made a separation of the probing systems into a few basic categories, description of the typical representatives of these categories and of the other important accessories of the coordinate measuring machines, too. The second part of the thesis contains a description of the Equator gauging system, the industrial robot which I used and their accessories. In this part is mentioned a few examples of measurement automation in industry practice, too. The third part devotes to the design of the robotized workcell and contains all the important requirements for the realization.
293

Mobile phone based applications in implementing cholera prevention and control education in complex humanitarian emergencies : a feasibility study in Mogadishu, Somalia

Kinyanjui, Jesee Wainaina 02 1900 (has links)
The aim of this study was to identify and describe the viability of using cell phones to conduct rapid assessments, pass key health messages and conduct monitoring and evaluation in complex emergencies. The study setting was in a cholera outbreak response situation in Mogadishu, the capital of war torn Somalia. Qantitative, descriptive research was conducted to determine the feasibility. Data collection was done using structured questionnaires, self-response mailed questionnaires as well as follow-up telephone interviews. Three groups of respondents participated in the study. The respondent groups included 383 internally displaced persons (IDPs), 5 water, sanitation and hygiene (WASH) specialists and 5 specialists from 5 mobile phone providers in Mogadishu. The study showed that there is good potential for an effective, cost efficient and scalable short message service (SMS) based public health education platform in Somalia. The study has also come up with recommendations on key considerations to ensure viability of the Public health education platform. It is envisaged that the recommended platform shall increase speed, access, spontaneity, coverage and reduced cost per capita, a combination of which form the hallmark of a good emergency health response. Ultimately this effort shall contribute to improved health, reduced suffering and reduced deaths in fragile humanitarian contexts. / Health Studies / M.A. (Public Health)
294

Computer Mediated Communication: Perceptions of Academic Advisors Regarding Text Messaging in Higher Education

Looney, Kathryn 02 March 2022 (has links)
No description available.
295

Phytoremédiation d’un sol contaminé par des contaminants organiques et inorganiques

Fortin Faubert, Maxime 04 1900 (has links)
Le nombre important de sites contaminés au Québec (Canada) et partout dans le monde est une problématique de santé publique majeure en raison des risques toxicologiques qu’ils présentent pour la santé humaine et environnementale. Dans la municipalité de Varennes (Québec, Canada), située sur la rive sud de l'Île de Montréal, les activités d’une ancienne usine pétrochimique (Pétromont Inc.) ont conduit à l’accumulation de concentrations modérées à élevées d’éléments traces métalliques (ETMs), de biphényles polychlorés (BPCs), d’hydrocarbures pétroliers aliphatiques (C10-C50) et d’hydrocarbures aromatiques polycycliques (HAPs) sur les terrains de la compagnie. En 2010, une culture intensive de saule sur courtes rotations (CICR) a été établie sur le site, afin d’y conduire une expérience de phytoremédiation à grande échelle. Bien que cette plantation de Salix miyabeana ait été implantée dans une optique d'assainissement, aucun effet significatif n'a été signalé sur la concentration des contaminants du sol au cours des premières années de croissance. Les processus d'assainissement basés sur l’utilisation de végétaux peuvent être difficiles à prévoir en milieux naturels et nécessitent des améliorations afin d'en augmenter leur efficacité. La fertilisation des sols avec des amendements organiques, ainsi que la manipulation du microbiome végétal, sont deux techniques agronomiques couramment utilisées pour la gestion des cultures traditionnelles, afin d’augmenter la production de biomasse et améliorer la santé générale des végétaux. Ces approches peuvent également influencer la mobilité et la biodisponibilité de certains composés du sol. Puisque de telles modifications sont connues pour avoir le potentiel d’améliorer considérablement l’efficacité des végétaux à éliminer ou à transformer certains contaminants du sol, ces deux techniques agronomiques présentent un intérêt grandissant dans le domaine de la phytoremédiation. Cette recherche doctorale vise donc à améliorer les connaissances scientifiques dans le domaine de la phytoremédiation appliquée à grande échelle en abordant certains aspects qui touchent à ces deux approches agronomiques. En utilisant la plantation de saules déjà établie, une première étude a été réalisée afin d’évaluer l’impact d’un amendement de sol organique sur l’efficacité phytoremédiatrice des deux cultivars de saules (‘SX61’ et ‘SX64’). À l’intérieur de cette plantation, le sol de certaines parcelles expérimentales a été recouvert de bois raméal fragmenté (BRF) de saules, combiné, ou non, avec du substrat de champignons épuisé (SCE) de Pleurotus ostreatus. Après trois saisons de croissance, les résultats ont montré que l’ajout de SCE au BRF n’avait eu aucun effet sur la croissance des saules, ainsi que sur leur efficacité à extraire ou à réduire la concentration des contaminants présents sur le site. Les résultats suggèrent néanmoins que le BRF contribue à immobiliser certains HAPs dans le sol, en plus d’augmenter l’efficacité des saules à phytoextraire le Zn. La présence de saules semble avoir réduit de façon significative l’atténuation naturelle des C10-C50 sur le site. De plus, les concentrations de BPCs, de Cd, de Ni et de dix HAPs, ont montré des oscillations saisonnières, ce qui suggère que l’évapotranspiration qui a lieu à l’intérieur de la plantation de saules provoque un important flux d'eau et de contaminants solubles en direction des racines. Ainsi, la concentration de certains contaminants pourrait avoir tendance à augmenter à l’intérieur d’une dense plantation de saules au fil du temps. Une deuxième étude a été réalisée à l’intérieur de cette même plantation, afin de vérifier si les augmentations de concentration observées précédemment pouvaient être liées à l’évapotranspiration qui a lieu à l’intérieur d’une plantation de saules. Dans l’optique d’éliminer l’effet de transpiration, des coupes de saules ont été effectuées dans certaines parcelles de la plantation, puis les concentrations des contaminants organiques et inorganiques ont été suivies au fil du temps (24 mois), et comparées avec celles observées dans les parcelles non coupées. Les résultats obtenus ont montré que l'élimination des saules avait bel et bien limité l'accumulation de certains contaminants à la surface du sol, tels qu’observé dans les parcelles non coupées. Ces résultats suggèrent donc encore une fois que la culture intensive de saules à courte rotation peut entrainer une migration de certains contaminants en direction des racines et ainsi augmenter leurs concentrations à la surface du sol près des zones racinaires. Très peu d’études ont rapporté des résultats qui semblent contredire les multiples avantages de purification qui sont habituellement mis de l’avant en phytoremédiation. Toutefois, de tels effets sur la mobilisation des contaminants pourraient être pertinents et souhaitables dans un contexte de gestion du risque. La troisième et dernière étude présentée dans cette thèse explore la diversité des communautés microbiennes associées aux racines des deux cultivars de saules établis sur le site expérimental depuis plusieurs années (six années). Des études antérieures ont permis d’en apprendre davantage sur la composition du microbiome racinaire et rhizosphérique du saule poussant en milieux contaminés, mais la plupart de celles-ci ont été menées sur des individus relativement jeunes. Par conséquent, peu d’information existe concernant les associations microbiennes des individus plus âgés qui ont été établis en milieux contaminés. La caractérisation des communautés fongiques, bactériennes et archéennes a permis de montrer des différences de composition entre les deux cultivars de saules, ainsi qu’entre leurs compartiments (i.e. racines et rhizosphère). Certains groupes taxonomiques, appartenant à chacun des trois domaines, se sont démarqués, de par leur abondance, ou par leurs fonctions écologiques déjà connues et potentiellement bénéfiques pour la survie des végétaux, ou pour augmenter la dégradation et l'extraction de divers contaminants. Cette étude fournit donc de précieuses informations qui pourront servir à l’amélioration de certaines approches d'ingénierie du microbiome favorisant l'établissement, la survie, la croissance et les performances d’assainissement de Salix spp. établis en milieux contaminés. L’ensemble des résultats présentés dans cette thèse ont permis d’alimenter différentes réflexions sur l’intérêt d’utiliser certains amendements organiques et de caractériser le microbiome racinaire et rhizosphérique des saules afin d’améliorer les pratiques et la mise en oeuvre de la phytoremédiation par des saules. Cette thèse met également en lumière un phénomène de migration des contaminants, influencé par la présence de plantes à croissance rapide, qui représente un obstacle pour l’évaluation des performances d’assainissement par des approches de phytoremédiation notamment par des saules. / The large number of contaminated sites in Quebec (Canada) and all around the world is a major public problem because of the toxicological risks they present for human and environmental health. In the municipality of Varennes (Quebec, Canada), located on the south shore of the Island of Montreal, the activities of a former petrochemical plant (Pétromont Inc.) have led to the accumulation of moderate to high concentrations of traces elements (TEs), polychlorinated biphenyls (PCBs), aliphatic petroleum hydrocarbons (C10-C50) and polycyclic aromatic hydrocarbons (PAHs) on the land. In 2010, a short rotation intensive culture (SRIC) of willow has been established on the site, in order to conduct a field-scale phytoremediation experiment. Although this plantation of Salix miyabeana was established with a remediation view, no significant effect was reported on the concentration of soil contaminants during the first years of growth. Plant-based remediation processes can be difficult to predict in the fiel and require improvement in order to increase their effectiveness. Fertilization with organic amendments, as well as manipulating the plant microbiome, are two agronomic techniques commonly employed in traditional crop management, in order to increase biomass production and improve overall plant health. These approaches can also influence the mobility and bioavailability of some compounds in the soil. Since such modifications are known to have the potential to significantly improve the efficiency of plants in removing or transforming soil contaminants, these two agronomic techniques are of growing interest in the field of phytoremediation. This doctoral research aims to improve scientific knowledge in the field-scale phytoremediation application by addressing some aspects that affect these two agronomic approaches. Inside the already established willow plantation, a first study was carried out to assess the impact of soil organic amendment on the phytoremediation efficacy of the two willow cultivars (‘SX61’ and ‘SX64’). The soil of some experimental plots was covered with ramial chipped wood (RCW) combined or not with spent mushroom substrate (SMS) of Pleurotus ostreatus. After three growing seasons, the results showed that the addition of SMS to the RCW had no effect on the growth of the willows, as well as on their effectiveness in removing or reducing the concentration of contaminants on the site. The results nevertheless suggest that RCW helps immobilize some PAHs in the soil, in addition to increasing the efficiency of willows to phytoextract Zn. The presence of willows appears to have significantly reduced the natural attenuation of C10-C50 on the site. In addition, the concentrations of PCBs, Cd, Ni and ten PAHs, showed seasonal oscillations, which suggests that the evapotranspiration inside the willow plantation mobilized some contaminants towards the rooting zones. Thus, the concentration of certain contaminants may tend to increase within a dense willow plantation over time. A second study was carried out inside the same plantation, in order to verify if the increases in concentration observed previously could be linked to the evapotranspiration that takes place inside a willow plantation. In order to eradicate the effect of plant transpiration, willows were harvested in certain plots of the plantation. The concentrations of organic and inorganic contaminants were followed over time (24 months) and compared with those observed in the unharvested plots. The results obtained showed that the removal of the willows limited the accumulation of certain contaminants on the soil surface, as observed in the uncut plots. These results suggested once again that the short rotation intensive culture of willows can lead to the migration of certain contaminants towards the roots and thus increase their concentrations on the soil surface near the root zones. Very few studies have reported results that seem to contradict the multiple purification benefits that are usually put forward in phytoremediation. However, such effects on contaminant mobilization could be relevant and suitable in a risk management context. The third and final study presented in this thesis explores the microbial communities associated with the roots of the two willow cultivars established on the experimental site for several years (six years). Root and rhizosphere microbial communities of Salix spp. have been studied in contaminated environments, but most of studies have been carried out on relatively young hosts. Therefore, little information exists regarding the microbial communities associated with older willows established in contaminated environments. The characterization of fungal, bacterial and Archean communities has shown differences in composition between the two willow cultivars, as well as between their compartments (i.e., roots and rhizosphere). Some taxonomic groups, belonging to each of the three domains, caught our attention, either by their abundance, or by their ecological functions already known to be potentially beneficial for the plant survival, or for increasing the degradation and extraction of various contaminants. This study therefore provides valuable information that can be used to improve certain microbiome engineering approaches that promote the establishment, survival, growth and phytoremediation performance of Salix spp. in contaminated environments. All the results presented in this thesis have fueled various reflections on the interest of using soil organic amendments and characterizing the root and rhizosphere microbiome of willows in order to improve the practices and implementation of phytoremediation with willows. This thesis also highlights a phenomenon of contaminant migration, influenced by the presence of fast-growing woody plants, which represents an obstacle for the evaluation of phytoremediation performance approaches with willows.
296

Improving Steering Module Efficiency for Incremental Loading Finite Element Numeric Models

Kitchen, Ryan L. 22 March 2006 (has links) (PDF)
Engineers frequently use computerized numeric models to calculate and predict water levels and current patterns for rivers, bays, and other bodies of water. This computation often involves an iterative process known as incremental loading that can cause frustration and consume a lot of time. Although the steering module in the Surface-water Modeling System (SMS) automates incremental loading to minimize user interaction, it can still be very time consuming. This thesis examines the steering module and the incremental loading process to improve its efficiency. Specifically, the RMA2 and FESWMS models are utilized. Two methods of improving efficiency are examined. The first includes creating predicted solution files for each step of the incremental loading process. These predictions allow the steering module to take larger steps and decrease the computation time. The second method changes the algorithm used to determine the size of each step. Finally, the interface to the process was examined and simplified to require minimal input and to make the input more intuitive.
297

Analysis of the Sediment Transport Capabilities of FESWMS FST2DH

Ipson, Mark K. 19 August 2006 (has links) (PDF)
Many numeric models simulate the transport of sediment within rivers and streams. Engineers use such models to monitor the overall condition of a river or stream and to analyze the impact that the aggradation and degradation of sediment has on the stability of bridge piers and other features within a stretch of a river or stream. A model developed by the Federal Highway Administration, FST2DH, was recently modified to include the simulation of sediment movement within a channel. The tools for modeling sediment movement with FST2DH remain unproven. This thesis examines the sediment capabilities of FST2DH. It evaluates the sediment results for reasonableness and compares the results to those obtained from a sediment transport model developed by the Army Corps of Engineers, SED2D WES. Resulting concentrations from another program created by the Army Corps of Engineers, SAMwin, provide additional data comparison for FST2DH sediment solutions. Several test cases for laboratory flumes give additional insight into the model's functionality. Finally, this thesis suggests further enhancements for the sediment capabilities of the FST2DH model and provides direction for future research of the sediment transport capabilities of FST2DH. Results show that FST2DH appropriately models sediment movement in channels with clear-water and equilibrium transport rate inflow conditions. Transport formulas found to be functional include the Engelund—Hansen, Yang sand and gravel, and Meyer-Peter—Mueller equations. FST2DH has difficulty modeling channels with user-specified inflow concentrations or transport rates, models with very small particles, models containing hydraulic jumps, and models with small elements. The test cases that successfully run to completion provide appropriate patterns of scour and deposition. Other trends in the results further verify the functionality of many of the sediment transport options in FST2DH.
298

數位時代下垃圾訊息法制之建置---以美國法為藍本

蔡欣惠, Tsai, Hsin-huei Unknown Date (has links)
當您看到此份研究計畫書時,五分鐘內可能您的e-mail郵箱已湧進二十封垃圾郵件(通稱SPAM)。據Ferris Research指出,社會花費在圍堵垃圾郵件的成本開銷上一年高達一百億美元。而根據聯合國國際電信聯盟(International Telecommunication Union,ITU)統計, Spam每年更浪費全球各國250億美元。這個驚人的數據傳達出一個訊息:對多數人而言-聽到「You've Got Mail!」,已經不再是令人愉悅的聲音了。Spamhaus的調查報告顯示 ,台灣及HINET一直是垃圾郵件主要輸出來源,過去AOL曾封鎖由HINET 寄送的郵件,一度造成台灣HINET使用者相當大的困擾。隨著數位匯流(Digital Convergence)時代的來臨,除了Email Spam外,電話行銷、Mobile Spam、SMS簡訊SPAM及VoIP都是數位匯流時代下垃圾郵件客攻掠的戰場,而我國行政院所草擬之「濫發商業電子郵件管理條例」草案明文只規範垃圾「郵件」問題,而未及其它垃圾訊息,法律若未對此議題及早規範,可能草案還沒出立法院大門就已經被時代淘汰。 因此,本文欲針對數位時代下可能興起之垃圾訊息型態作全面性的檢討,以建構一更為完善的垃圾訊息法制已未雨綢繆。本文之研究方法如下: 第一,針對美國之垃圾訊息法制的內容與立法背景,進行比較法研究。台灣的濫發商業電子郵件管制條例草案,內容主要係參考美國法,但在若干立法例仍有所不同,例如於是否需要標示主旨欄(Subject Line Labeling)則有不同選擇。對此,筆者曾於在律師雜誌發表對美國聯邦貿易委員會(FTC)研究報告反對強制行銷業者寄送廣告信必需標示主旨欄的不同意見,且建議台灣的「濫發商業電子郵件管制條例」草案做相反規定 。此外,在處罰對象及門檻之設計亦大相逕庭,例如沒有刑罰規定。而在於規制主體上,我國草案的內容明文只限於垃圾『郵件』之規範,對於日益惡化的的新型態未經邀約的商業訊息,像是透過無線傳輸設備或是行動設備所接收的未經邀約之商業訊息等,草案並無法可管。因此,本文並將針對垃圾電子郵件以外的其它新興垃圾訊息法制進行說明與分析,以供未來立法及執法的參考。 再者,本文將藉由國內外的實務案例研究了解法律實際操作情況。因為台灣法律目尚前無法處理垃圾郵件這個新興法律問題,導致檢察官無法可用,之後通過草案亦可能會面臨到法律不足的問題,因此實有必要針對實際案例操作深入了解。 第三,本文擬就我國之「濫發商業電子郵件管理條例草案」內容進行通盤檢討,提出更符合數位匯流時代之法制架構,以更有效防堵垃圾訊息。美國史丹佛教授Dr. Dan Boneh在「the Difficulties of Tracing Spam Email」 一文中提及垃圾郵件客技術日新月異,防不勝防。可預見SPAM這個議題將隨著科技演進而日益嚴重。隨著數位匯流(Digital Convergence)時代的來臨,除了垃圾郵件外,電話行銷、行動簡訊(Mobile Spam)、簡短訊息服務SMS 及網路語音(Voice over Internet Protocal)、多媒體圖片訊息(MMS)都是數位匯流時代下垃圾郵件客攻掠的戰場,實有必要針對此些新興類型之Spam進行防範。 / Within the five minutes it takes for you to read this essay, your e-mail box may have already received 20 spam mails. Ferris Research has pointed out that the costs incurred to society in blocking spam has reached US$10 billion per year. And according to International Telecommunication Union (ITU), the annual global cost of spam is US$2.5 billion. These startling figures convey a bit of information: for most people, the message “You’ve got mail!” is no longer welcome.. Based on a survey conducted by Spamhaus, Taiwan is a leading source of spam messages. AOL once blocked all e-mail messages coming from Hinet, which at one blow caused huge difficulties for Taiwanese Internet users. With the coming of the Digital Convergence era, besides e-mail spam, new forms are emerging such as mobile spam, telemarketing calls, SMS messaging spam, and VoIP spam. The Digital Convergence era will provide all kinds of opportunities for spammers to attack. However, Taiwan’s draft Anti-UCE Act addresses only e-mail spam. If the law does not address the broader issue early on, it may be outmoded even before it is passed. The US remains the main source of reference for Taiwan in the area of technology law. Long ago, before the US enacted the “Can-Spam Act,” there was “Shiksaa.” I would like to do in-depth research on American cyber and technology law so I can develop a suitable legal solution to Taiwan’s very serious UCE problem, to reduce the losses to society and to business productivity that are caused by spam, to eliminate Taiwan’s bad reputation for being a main spam exporter, and to spur e-commerce development. My research project would be as follows. 1. To examine the inner traits of various SPAM regulation and do interdisciplinary research 2. Deploy case-based and comparative law study to gather practical material 3. Combine the research results from technology and law to contribute to the ultimate resolution of SPAM.

Page generated in 0.032 seconds