<p>Unmanned aerial vehicles (UAV) have revolutionized data collection in large scale agronomic field trials (10+ ha). Vegetative index (VI) maps derived from UAV imagery are a potential tool to characterize temporal and spatial treatment effects in a more efficient and non-destructive way compared to traditional data collection methods that require manual sampling. The overall objective of this study was to characterize and quantify maize responses to experimental treatments in field-scale research using UAV imagery. The specific objectives were: 1) to assess the performance of several VI as predictors of grain yield and to evaluate their ability to distinguish between fertilizer treatments, and the effects of removing soil and shadow background, 2) to assess the performance of VI and canopy cover fraction (CCF) as predictors of maize biomass at vegetative and reproductive growth stages under field-scale conditions, and 3) to compare the performance of VI derived from consumer-grade and multispectral sensors for predicting grain yield and identifying treatment effects. For the first objective, the results suggest that most VI were good indicators of grain yield at late vegetative and early reproductive growth stages, and that removing soil background improved the characterization of maize responses to experimental treatments. For objective two, overall, CCF was the best to predict biomass at early vegetative growth stages, while VI at reproductive growth stages. Finally, for objective three, performance of consumer-grade and multispectral derived VI were similar for predicting grain yield and identifying treatment effects.</p>

Despite decades of research robotic manipulation systems outside of highly-structured industrial applications are still far from ubiquitous. Perhaps particularly curious is the fact that there appears to be a large divide between the theoretical grasp modeling literature and the practical manipulation community. Specifically, it appears that the most successful approaches to tasks such as pick-and-place or grasping in clutter are those that have opted for simple grippers or even suction systems instead of dexterous multi-fingered platforms. We argue that the reason for the success of these simple manipulation systemsis what we call passive stability: passive phenomena due to nonbackdrivable joints or underactuation allow for robust grasping without complex sensor feedback or controller design. While these effects are being leveraged to great effect, it appears the practical manipulation community lacks the tools to analyze them. In fact, we argue that the traditional grasp modeling theory assumes a complexity that most robotic hands do not possess and is therefore of limited applicability to the robotic hands commonly used today. We discuss these limitations of the existing grasp modeling literature and setout to develop our own tools for the analysis of passive effects in robotic grasping. We show that problems of this kind are difficult to solve due to the non-convexity of the Maximum Dissipation Principle (MDP), which is part of the Coulomb friction law. We show that for planar grasps the MDP can be decomposed into a number of piecewise convex problems, which can be solved for efficiently. Despite decades of research robotic manipulation systems outside of highlystructured industrial applications are still far from ubiquitous. Perhaps particularly curious is the fact that there appears to be a large divide between the theoretical grasp modeling literature and the practical manipulation community. Specifically, it appears that the most successful approaches to tasks such as pick-and-place or grasping in clutter are those that have opted for simple grippers or even suction systems instead of dexterous multi-fingered platforms. We argue that the reason for the success of these simple manipulation systemsis what we call passive stability: passive phenomena due to nonbackdrivable joints or underactuation allow for robust grasping without complex sensor feedback or controller design. While these effects are being leveraged to great effect, it appears the practical manipulation community lacks the tools to analyze them. In fact, we argue that the traditional grasp modeling theory assumes a complexity that most robotic hands do not possess and is therefore of limited applicability to the robotic hands commonly used today. We discuss these limitations of the existing grasp modeling literature and setout to develop our own tools for the analysis of passive effects in robotic grasping. We show that problems of this kind are difficult to solve due to the non-convexity of the Maximum Dissipation Principle (MDP), which is part of the Coulomb friction law. We show that for planar grasps the MDP can be decomposed into a number of piecewise convex problems, which can be solved for efficiently. We show that the number of these piecewise convex problems is quadratic in the number of contacts and develop a polynomial time algorithm for their enumeration. Thus, we present the first polynomial runtime algorithm for the determination of passive stability of planar grasps. For the spacial case we present the first grasp model that captures passive effects due to nonbackdrivable actuators and underactuation. Formulating the grasp model as a Mixed Integer Program we illustrate that a consequence of omitting the maximum dissipation principle from this formulation is the introduction of solutions that violate energy conservation laws and are thus unphysical. We propose a physically motivated iterative scheme to mitigate this effect and thus provide the first algorithm that allows for the determination of passive stability for spacial grasps with both fully actuated and underactuated robotic hands. We verify the accuracy of our predictions with experimental data and illustrate practical applications of our algorithm. We build upon this work and describe a convex relaxation of the Coulombfriction law and a successive hierarchical tightening approach that allows us to find solutions to the exact problem including the maximum dissipation principle. It is the first grasp stability method that allows for the efficient solution of the passive stability problem to arbitrary accuracy. The generality of our grasp model allows us to solve a wide variety of problems such as the computation of optimal actuator commands. This makes our framework a valuable tool for practical manipulation applications. Our work is relevant beyond robotic manipulation as it applies to the stability of any assembly of rigid bodies with frictional contacts, unilateral constraints and externally applied wrenches. Finally, we argue that with the advent of data-driven methods as well as theemergence of a new generation of highly sensorized hands there are opportunities for the application of the traditional grasp modeling theory to fields such as robotic in-hand manipulation through model-free reinforcement learning. We present a method that applies traditional grasp models to maintain quasi-static stability throughout a nominally model-free reinforcement learning task. We suggest that such methods can potentially reduce the sample complexity of reinforcement learning for in-hand manipulation.We show that the number of these piecewise convex problems is quadratic in the number of contacts and develop a polynomial time algorithm for their enumeration. Thus, we present the first polynomial runtime algorithm for the determination of passive stability of planar grasps.

Includes bibliographical references / Although learning management systems (LMSs) have been widely adopted by universities in developing countries, their potential to support students' learning has not been fully exploited due to several factors. Some of the factors limiting the more successful implementation of LMSs in developing country universities have been identified and reported in this study. Most importantly, LMS implementation in developing country universities is constrained by limited institutional ICT infrastructures, Internet bandwidth and electricity outages that affect the accessibility of LMS services by the students. The main research question addressed in this study is: How can we better use the available ICTs and ICT infrastructure in developing country universities to enhance the accessibility of the LMS services by students to better support the implementation of LMSs? The research question was addressed through surveys and experimentation. Two surveys were carried out, and the findings of these surveys were useful in: understanding the current state of practice in LMS implementation in developing country universities; defining the problem; understanding the students' LMS expectations and needs; and deciding the nature of the intervention to be implemented. Through the surveys, it was established that the majority of students in the surveyed universities possessed mobile phones, most of which being internet enabled phones. The study therefore explored the possibility of enabling and enhancing mobile access for LMS services so as to enhance students' LMS accessibility through their mobile phones. The design, development, implementation and evaluation of the intervention (the mobile LMS) were achieved through a user-centred development approach that included participatory design, prototyping and user experience evaluation. An impact evaluation of the mobile LMS intervention indicated that: mobile LMS interfaces can lead to students' increased access and use of the LMS through mobile phones; students prefer streamlined mobile LMS interfaces with fewer and block-based services; with streamlined mobile LMS interfaces, students are able to get the LMS services they need on their mobile phones without the need for desktop and laptop computers and without the need for the full desktop LMS interfaces. While the streamlined mobile LMS allows the students an opportunity to more satisfactorily access the LMS services through their mobile phones, it also takes away the pressure from the constrained institutional ICT infrastructure and facilities such as computer laboratories. The design and development process of the mobile LMS intervention highlighted that students' involvement leads to creation of more usable and useful mobile LMS interfaces and that most of the students' mobile LMS needs can be achieved through a cross-platform mobile Web application.

Propaedeutics of Differential and Integral Calculi Author: Ing. Martin Malachov Department: Department of Mathematics Education Supervisor: Zdeněk Halas, DiS., Ph.D. Department of Mathematics Education Keywords: propaedeutics, derivative, Riemann integral, applications Differential and integral calculi both are interesting and beautiful branches of mathematics with many interdisciplinary overlaps and significant and practi- cal applications. Learning as well as teaching of these topics is very difficult and demanding. In this thesis we show that the derivatives and integrals have much to offer in the high school education while the schooling can be eased and made attractive with intentional propaedeutics and knowledge of rich background of applications. First part of the thesis presents short contem- plation on the current state of teaching and literature, we focus on the urge for the propaedeutics of the differential and integral calculi revealed by us. We identify key terms that can be used to build useful preconcepts during the whole high school education, even in the elementary education. In the latter part of the thesis we offer teacher innovative texts and a rich set of origi- nal exercises that can be used for motivation, application and propaedeutics of the differential and integral calculi. We also present...

A mobile application has to be able to keep up with heavy demands to compete with all the new applications that are developed each day. Good performance and nice visuals are base requirements for the development of mobile applications. There are many options for tools when developing and one of these choices is a native application, which is said to have better performance and suitability to the mobile environment. Another choice is a tool which requires only one code base for multiple platforms and is therefore easier to maintain. Flutter is an open-source User Interface (UI) toolkit created by Google that can create cross-platform applications with one code base while said to maintain the aspects of looking native. This paper explores how Flutter compares to native applications, which are currently seen as superior in mobile behaviour and performance. An experiment was conducted to test how Flutter as a cross-compiler compared to two native applications made of kotlin and Android studio and swift and XCode, in terms of CPU performance. A survey was created to see if there was a difference in the perception of users with regards to appearance and animations. A literature study was conducted to strengthen the results from the experiment and survey and to give a background to the subject. Flutter is a new tool and it continues to grow incredibly fast. Conclusions are drawn that a Flutter application can compete with a native application when it comes to CPU performance, but is not as developed in the animation area. Flutter does not require complex code for creating a simple application and uses significantly less lines of code in development compared to native. The final conclusion is that Flutter is best to use when building smaller to medium-sized applications, but has a potential to grow to overcome its current drawbacks in the animation department. Further examination of the areas examined in this paper is needed in order to ensure and strengthen the results.

Magnetic cooling is an emerging refrigeration technology with potential to surpass the performance of vapour compression devices. It has been successfully applied in the cryogenic temperature ranges, where magnetic cooling gas liquefiers surpass the performance of conventional liquefaction systems. Magnetic refrigeration technology is based on the magnetocaloric effect, a characteristic present in all magnetic materials and alloys. In magnetic thermodynamic cycles, magnetization of a magnetocaloric material is equivalent to the compression of a gas, while demagnetization is equivalent to expansion of a gas, with a subsequent diminution of the entropy. In this thesis, the applicability of this technology to the domestic environment is reviewed. First, the thermodynamics of magnetic refrigeration are explored. Then, a comprehensive review of magnetocaloric materials suitable for use at room temperature is presented. To ascertain the state of the art, the most relevant prototypes and their performances have been described. Concluding the documentation, a survey on the existing mathematic models has been performed, that provided the foundation to create a Matlab model of a magnetic refrigeration device. To gain greater insight on the internal working of these devices, a representative room temperature cooling device has been modelled, and used to simulate a magnetic refrigerator and room air conditioner. Its performance has been analysed and compared with that of vapour compression devices. Also, the influence of parameters such as magnetic field applied, temperature span, refrigerant fluid and different regenerator configurations has been investigated.

<p>QC 20131115</p>

HydroShare is a collaborative online system being developed by the Consortium of Universities for the Advancement of Hydrologic Science Inc. (CUAHSI) with the goal of facilitating the dissemination, visualization, and publishing of hydrologic data and models. External web applications serve a key role in extending HydroShare's capabilities, so robust application programming interfaces (APIs) are a vital component of HydroShare's architecture. Hydrologic data stored on HydroShare are defined by a data type, and much of these data are either geospatial or time series data. Although HydroShare's API provides ways to upload and download files, as well as access certain metadata, it does not currently provide GIS services defined by the Open Geospatial Consortium, or Hydrologic Information System (HIS) services developed by CUAHSI. The absence of these services severely limits the capabilities of HydroShare apps while also increasing the development time and complexity of apps that are developed.To help alleviate this disconnect between HydroShare and HydroShare apps, I have developed a system which helps extend HydroShare's data service capabilities using GeoServer and a Water Data Server to expose GIS and HIS data services for HydroShare content. With this system in place, HydroShare apps have much better access to HydroShare content, allowing them to be developed in less time, and provide much more powerful visualization, access, and analysis services to HydroShare users.

Mobile web browsers of today have many of the same capabilities as their desktop counterparts. However, among the capabilities they lack is a way for web applications to interact with local devices. While today’s mobile phones commonly include GPS receivers and digital cameras, these local devices are currently not accessible from within the browser. The only means of utilizing these devices is by using standalone applications, but such applications lack the versatility of web browsers. If a mobile browser could utilize these local devices, then a mobile application could run within the browser, thus avoiding the need for specialized client software. This thesis suggests an approach for adding such capabilities to mobile browsers. In the proposed method, scripted access to local device functionality is facilitated by a local Java application. This application acts as a proxy server and allows the browser to call methods exposed by the local Java APIs. Both the benefits and some security concerns of this approach are examined. The benefits are further highlighted through two example web applications which utilize local devices. / I dagens mobila webbläsare återfinns det mesta av funktionaliteten från webbläsare för datorer. Det som dock fortfarande saknas är möjligheten för webbapplikationer att komma åt lokala telefonfunktioner. Dagens mobiltelefoner är ofta utrustade med GPS-mottagare och digitalkameror, men dessa kan för närvarande ej nås från webbläsaren. Det enda sättet att utnyttja dessa inbyggda funktioner är genom separata applikationer, men sådana applikationer är inte lika mångsidiga som webbläsare. Om en mobil webbläsare kunde utnyttja de inbyggda funktionerna, så skulle en mobil applikation kunna köras i webbläsaren istället för att ha separat klientprogramvara. Det här examensarbetet föreslår ett sätt att ge denna möjlighet till mobila webbläsare. I den föreslagna metoden används en lokal Java-applikation för att ge tillgång till inbyggda funktioner via skript. Denna applikation fungerar som en proxy-server och låter webbläsaren anropa metoder exponerade av lokala Java-API. Både fördelar och några säkerhetsproblem med den här lösningen undersöks. Fördelarna visas ytterligare genom två exempel på webbapplikationer som utnyttjar inbyggda telefonfunktioner.

The aim of this study is to investigate how and in which form students come in contact with practical applications in the upper secondary school course Chemistry B. The study is based upon the assumption that all learning is situated in a social environment. The theoretical framework is the design theory perspective, which entails an assumption that the pedagogical tools affect the knowledge content. The empiric materials in the study are collected through three methods: textbook analysis, classroom observations and questionnaires. Two groups of students and their teachers were observed during a section of the relevant course. The textbook analysis focuses upon the same course section in the textbooks of the two groups and compares these books with the relevant section in a third textbook. In addition, the two student groups responded to a questionnaire on their attitudes toward the subject of chemistry subject linked to its applications at a society level. The study shows that there are significant differences between the strategies which teachers and textbooks use in order to present and visualise practical applications of chemical theory. The context strategy is based upon the students’ own surroundings and uses real life application as a tool for the presentation of the principles of chemistry. According to this strategy, the knowledge content should be organised in such a way that the chemical principles are used to explain our surroundings. The process and product strategy, on the other hand focuses upon a scientific approach, in which science as a process and scientific products are most important. With this strategy, applications are used to illustrate and exemplify the knowledge content. The conclusion of this study is that neither different forms of presentation nor the presence of practical applications affect the students' attitude towards the subject. Furthermore, practical applications are not a significant part of the students' learning strategies.