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Desarrollo de un equipo electrónico/computacional orientado a extraer información de interés para el diagnóstico de Mildiu en plantaciones de quinua de la costa peruana basado en procesamiento digital de imágenesOré Huacles, Gian Carlos, Vásquez García, Alexis 03 February 2021 (has links)
La presente tesis propone un equipo portátil y ergonómico que permita la captura de imágenes de cultivos de quinua y, mediante un método de procesamiento eficaz, detecte los segmentos donde la planta se encuentra afectada por la enfermedad del Mildiu (representada por un amarillamiento particular sobre las hojas) para así obtener un resultado numérico que represente dicho efecto. La realización de este proyecto resuelve el principal problema del análisis cualitativo en los que se basa el cliente para el diagnóstico de la enfermedad ya que ofrecerá una solución cuantitativa para la identificación y medición de daño en los cultivos que proporcione al agrónomo un dato vital para poder suministrar la dosis adecuada de fungicida a las plantaciones y obtener un producto de mejor calidad. Este trabajo se basa en dos procesos de segmentación: primero, se realizó, a partir de la imagen original capturada, la segmentación de vegetación sobre el entorno mediante el modelo de color L*a*b, histograma bidimensional, filtrado y binarización; y, segundo, se realizó, a partir de la imagen resultante del primer proceso, la segmentación de amarillamiento sobre la vegetación mediante de los modelos de histogramas bidimensionales, filtrado, binarización y propiedades de excentricidad. Para la validación se tomó 50 imágenes de un cultivo de quinua del Instituto Nacional de Innovación Agraria (INIA) - Sede Lima, las cuales fueron procesadas a través del equipo desarrollado y verificado por el agrónomo especialista. Finalmente, se utilizó el índice de Kappa de Cohen para comparar los resultados donde se obtuvo un resultado de 0.789. / This thesis proposes a portable and ergonomic equipment that allows the capture of images of quinoa crops and, through an effective processing method, detect the segments where the plant is affected by Mildew disease (represented by a particular yellowing on the leaves) in order to obtain a numerical result that represents that effect. The realization of this project solves the main problem of the qualitative analysis on which the client is based for the diagnosis of the disease since it will offer a quantitative solution for the identification and measurement of crop damage that provides the agronomist with a vital data to be able to Supply the appropriate dose of herbicide to the plantations and obtain a better quality product. This work is based on two segmentation processes: first, from the original image captured, the segmentation of vegetation over the environment was carried out using the L*a*b color model, two-dimensional histogram, filtering and binarization; and, secondly, from the image resulting from the first process, the segmentation of yellowing on the vegetation was carried out using the two-dimensional histogram, filtering, binarization and eccentricity properties models. For validation, 50 images of a quinoa crop from INIA - Lima Headquarters were taken, which were processed through the equipment developed and verified by the specialist agronomist. Finally, Cohen’s Kappa index was used to compare the results where a result of 0.789 was obtained. / Tesis
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Arrangement Design Studies : the introduction of the digital wall in domestic environments / Designstudier av införandet av den digitala väggen i hemmiljöerAbdipour, Morteza January 2021 (has links)
This research focuses on the emergence of 'digital walls' that can project images onto almost all or even the entirety of interior (and perhaps exterior) walls, and what implications this might have for how we arrange our rooms. It demonstrates the arrangement, i.e., the way that domestic products are arranged physically, of rooms changes in the domestic environment in a complex scenario when using large screens. Due to the fast-growing demand for large screens, this product could potentially be available to be used by people in their home environments; however, it does not yet exist in reality at this scale. Constructing large screens can be carried out using different production methods. Here, this concept is called the digital wall, a very thin wall-sized interactive screen. The characteristics of the digital wall will vary to be able to create different scenarios. One such scenario is a space in the home where the surface of the wall is covered with screens, which allows multiple possibilities to experience and interact with digital content. In this research, the social gathering space of homes, nowadays called the living room, is considered as a highly relevant space for installing the digital wall. In this space, the conceptual framework outlines the basic elements of the research and demonstrates the relationships between people’s interactions with the digital wall and domestic products in the domestic environment. I show two examples from design history to understand how arrangement changes impact the home environment: the transformation of the parlor to the living room, and entry of the television into the living room. These two examples are focused on the place in the home where people gather for socializing. The discussion of these examples led to the elaboration of the relationships between the elements in the conceptual framework. I explored relevant design research methodologies to bring this future scenario into the present to understand the relationships between people and the digital wall. I applied research through design and the constructive design research approaches to frame the design research methodology. In this thesis, I set up seven series of design studies in two cluster groups: Supportive studies and Main studies. All of the design studies were conducted in the Design Research Lab, the actual space for carrying out the design experiments, prototyping the digital wall, and the setting of the experiments for user participation. The Lab was fully equipped with relevant technology and allowed me to use multiple methods to collect data while people were experiencing the design study sessions. The Lab was useful as a platform to understand user experiences, barriers for interactions as well as people's experiences in a simulated space of a domestic environment. The main contribution of this research is to understand the forms of arrangement changes when people use the digital wall in homes. The research demonstrates two significant implications that are seen in two forms of arrangements: tangible arrangement and imperceptible arrangement. These findings are useful for both designers and users of the elements of domestic contexts and the relations that can be shaped by the presence of a digital wall in home environments. This understanding may provide design guidelines in future scenarios in which the digital wall is used in homes. The findings are also beneficial for designing the domestic environment, improving the arrangement of space, and raising the requirements for designing domestic products.
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Einfluss des Experimentalraums auf biomechanische Messungen beim Laufen in unterschiedlichen LaufschuhenZaumseil, Falk 16 August 2017 (has links)
Die Fortbewegung des Menschen – ob gehend oder laufend – war und ist bis zum heutigen Tag im Fokus des wissenschaftlichen Interesses. Dabei gehört die Durchführung von etwaigen Studien im Labor zu einer anerkannten methodischen Verfahrensweise. Durch die stete technologische Weiterentwicklung von Messsystemen, bestehen nunmehr veränderte Möglichkeiten, wodurch das Laufen des Menschen in seinem natürlichen Bewegungsraum quantifiziert werden kann.
Ziel dieser Arbeit war es, den Einfluss des Experimentalraums auf das Laufen zu untersuchen. Zusätzlich wurde dabei die Rolle von drei Laufschuhen unterschiedlicher Kategorien genauer betrachtet. Für die Erhebung der zum Vergleich notwendigen Messgrößen diente zum einen ein Inertialsensor-System, um die Kinematik der Läufer zu erfassen und zum anderen EMG-System, um Rückschlüsse auf deren muskulären Status ziehen zu können.
In den Ergebnissen zeigte sich, dass nicht nur der Laufschuh sondern auch der Experimentalraum mit seinen jeweiligen Gegebenheiten Einfluss auf den Laufstil der Probanden nahmen. Generell kann aus den Ergebnissen abgeleitet werden, dass auf Grund der besseren Laufrhythmik im Feld, die Läufer einen messbar effizienteren Laufstil aufwiesen.
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Damage characteristics of brittle rocks inside the pre-failure range: numerical simulation and lab testingChen, Wei 12 October 2015 (has links)
The time-independent and -dependent damage characteristics of brittle rocks inside the pre-failure range have been investigated using numerical simulations and lab testing. Grain-based discrete element models have been developed to simulate both, time-independent and -dependent damage evolution leading to ultimate failure of sandstone and granite, respectively. The models take into account elastic grain and elasto-plastic contact deformation, inter- and intra-granular fracturing and lifetime prediction on the basis of subcritical crack growth. The time-independent mechanical behavior of Coconino sandstone and Lac du Bonnet granite during uniaxial compression tests, Brazilian splitting tests and fracture toughness tests was simulated. Triaxial compression tests and fracture toughness tests for Kirchberg II granite and fracture patterns tests for Eibenstock II granite were carried out in laboratory to perform time-independent damage and failure criterion analysis. The corresponding simulations showed reasonable damage phenomena compared with experimental results. Damage indices were deduced and were applied for different time-independent simulations. Based on calibrations of the time-independent damage simulations of selected brittle rocks, Charles equation and Hillig-Charles equation, which are generally used to describe subcritical crack growth, were implemented into the numerical code to simulate time-dependent damage. One-edged crack growth in Coconino sandstone specimen due to stress corrosion has been analyzed theoretically and numerically. Uniaxial compressive creep tests for Lac du Bonnet granite were simulated and time-dependent behavior in terms of the damage process during primary, secondary and tertiary creep until final failure characterized by macroscopic fracturing was discussed in detail. Subsequent to this, the time-dependent Mode-I crack growth tests and uniaxial compressive creep tests for Kirchberg II granite were carried out and the corresponding simulations were performed. Simulation results are in good agreement with experimental observations. In addition, damage indices and time-dependent fracture development were monitored and illustrated. The developed approach was applied to two potential practical applications: the damage analysis of a sandstone landscape arch and a tunnel. Finally, the results are summarized and recommendations for future work are proposed.:1 Introduction
2 State of the art
3 Time-independent damage analysis
4 Time-dependent damage analysis
5 Applications of numerical models .
6 Conclusions and outlook
References
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Behavior of jointed rock masses: numerical simulation and lab testingChang, Lifu 19 June 2019 (has links)
The anisotropic behavior of a rock mass with persistent and planar joint sets is mainly governed by the geometrical and mechanical characteristics of the joints. The aim of the study is to develop a continuum-based approach for simulation of multi jointed geomaterials. There are two available numerical techniques for the strain-stress analysis of rock masses: continuum-based methods and discontinuum based methods. Joints are simulated explicitly in discontinuous methodology. This technique provides a more accurate description for the behavior of a rock mass. However, in some projects, the explicit definition becomes impractical, especially with increasing number of joints. Besides, the calculation efficiency will be significant reduced as the number of joints increases within the model. Considering the above mentioned shortcomings of the discontinuous method, the continuum-based approach is widely used in rock mechanics. Within the continuum methods, the discontinuities are regarded as smeared cracks in an implicit manner and all the joint parameters are incorporated into the equivalent constitutive equations.
A new equivalent continuum model, called multi-joint model, is developed for jointed rock masses which may contain up to three arbitrary persistent joint sets. The Mohr-Coulomb yield criterion is used to check failure of the intact rock and the joints. The proposed model has solved the issue of multiple plasticity surfaces involved in this approach combined with multiple failure mechanisms. The multi-joint model is implemented into FLAC and is verified against the distinct element method (UDEC), analytical solutions, and experimental data. Uniaxial compression tests with artificial rock-like material (gypsum) are carried out in the laboratory in order to verify the developed constitutive model and to investigate the behavior of jointed specimen. Samples with two crossing joints covering more than 20 angle configurations and two different property sets were prepared and tested.
Simulation results are in good agreement with experimental observations. The developed model is applied to two potential practical applications: the stability analysis of a slope and a tunnel under different stress conditions. Finally, the main achievements of the whole PhD study are summarized and future research work is proposed.
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Non-Destructive Evaluation of the Condition of Subsurface Drainage in Pavement Using Ground Penetrating RADAR (GPR)Hao Bai (5929478) 14 December 2020 (has links)
<div>Pavement drainage systems are one of the key drivers of pavement function and longevity, and effective drain maintenance can significantly extend a pavement's service life. Maintenance of these drains, however, is often hampered by the challenge of locating the drains. Ground Penetrating Radar (GPR) typically offers a rapid and effective method to detect these underground targets. However, typical detection schema that rely upon the observation of the hyperbolic return from a GPR scan of a buried conduit still tend to miss many of the older drains beneath pavements as they may be partially or fully filled with sediment and/or may be fabricated from clay or other earthen materials, yielding a return signal that is convolved with significant background noise. </div><div><br></div><div>To manage this challenge, this work puts forward an improved background noise and clutter reduction method to enhance the target signals in what amounts to a constructed environment that tends to have more consistent subsurface properties than one might encounter in a general setting. Within this technique, two major algorithms are employed. Algorithm 1 is the core of this method, and plays the role of reducing background noise and clutter. Algorithm 2 is supplementary, and helps eliminate anomalous discontinuous returns generated by the equipment itself, which could otherwise lead to false detection indications in the output of Algorithm 1. Instead of traditional 2-D GPR images, the result of the proposed algorithms is a 1-D plot along the survey line, highlighting a set of “points of interest” that could indicate buried drain locations identified at any given GPR operating frequency. Subsurface exploration using two different operating frequencies, 900 MHz and 400 MHz herein, is then employed to further enhance detection confidence. Points of interest are ultimately coded to define the confidence of the detection. Comparing the final result of proposed algorithms with the original GPR images, the improved algorithm is demonstrated to provide significantly improved detection results, and could potentially be applied to similar problems in other contexts.</div><div><br></div><div>Besides the background reduction methods, a group of simulations performed using GPRMAX2D software are examined to explore the influence of road cross-section designs on sub-pavement drainage conduit GPR signatures, and evaluate the effectiveness of alternate GPR antennae configurations in locating these buried conduits in different ground conditions. Two different models were explored to simulate conduit detection. In addition, different pipe and soil conditions were modeled, such as pipe size, pipe material, soil moisture level, and soil type. Four different quantitative measurements are used to analyze GPR performance based on different key factors. The four measurements are 1) signal to background ratio (SBR) in dB; 2) signal to receiver noise ratio (SNR) in dB; 3) signal energy in Volts; and 4) average signal band power in Watts.</div><div><br></div><div>The water and clay content of subsurface soil can significantly influence the detection results obtained from ground penetrating radar (GPR). Due to the variation of the material properties underground, the center frequency of transmitted GPR signals shifts to a lower range as wave attenuation increases. Examination of wave propagation in the subsurface employing an attenuation filter based on a linear system model shows that received GPR signals will be shifted to lower frequencies than those originally transmitted. The amount of the shift is controlled by a wave attenuation factor, which is determined by the dielectric constant, electric conductivity, and magnetic susceptibility of the transmitted medium. This work introduces a receiver-transmitter-receiver dual-frequency configuration for GPR that employs two operational frequencies for a given test - one higher and one slightly lower - to take advantage of this phenomenon to improve subpavement drain detection results. In this configuration, the original signal is transmitted from the higher frequency transmitter. After traveling through underground materials, the signal is received by two receivers with different frequencies. One of the receivers has the same higher center frequency as the transmitter, and the other receiver has a lower center frequency. This configuration can be expressed as Rx(low-frequency)-Tx(high-frequency)-Rx(high-frequency) and was applied in both laboratory experiments and field tests. Results are analyzed in the frequency domain to evaluate and compare the properties of the signal obtained by both receivers. The laboratory experiment used the configuration of Rx(400MHz)-Tx(900MHz)-Rx(900MHz). The field tests, in addition to the configuration used in the lab tests, employed another configuration of Rx(270MHz)-Tx(400MHz)-Rx(400MHz) to obtain more information about this phenomenon. Both lab and field test results illustrate the frequency-shift phenomenon described by theoretical calculations. Based on the power spectrum for each signal, the lower frequency antenna typically received more energy (higher density values) at its peak frequency than the higher frequency antenna.</div>
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Utveckling av laboration om trefastransformatorn : En studie om transformatorer / Development of three phase transformer lab : A study about transformersAl-Breihi, Mohammed January 2014 (has links)
Examensarbetet har utforts pa uppdrag av enheten for Data- och Elektroteknik pa skolan for Teknik och Halsa, KTH. Denna studie om transformatorer omfattar deras funktioner och anvandningsomraden, hur de ar uppbyggda, hur karnan och lindningarna som ar transformatorns viktigaste delar ar uppbyggda, vilka materiel som anvands vid konstruktion av dessa samt vilka typer det finns av dem beskrivs i rapporten. Vidare beskrivs flera olika transformatortypers funktioner och anvandningsomraden. Eftersom en viktig del av studien varit pa vilka satt transformatorer kan utvecklas for okad miljovanlighet och livslangd gar rapporten igenom olika vegetabiliska oljor, vilka fordelar de har gentemot mineraloljor och vilka egenskaper de har samt pa vilket satt de ar skonsammare mot miljon. HVDC-enheter transformerar hoga spanningar fran vaxelspanning till likspanning for mindre resistiva forluster och darmed lagre energiforluster vilket i sin tur leder till en renare miljo. Teorigenomgangen av transformatorn ligger till grund for utformningen av en laboration for undervisningsbruk, bl.a. i en kurs om elkraftteknik som ges i hogskoleingenjorsprogrammet Elektroteknik pa KTH. / This degree project was carried out on behalf of the unit for Computer and Electrical engineering at the School of Technology and Health, KTH. This study about transformers, their function and uses, the way they’re built, how the core and windings, which are the most important parts of a transformer, are made and what kind of materials are used to make them. Several types of transformers and their functions are described. A crucial part of the study has been to search for different ways to develop transformers to make them environmentally safer and to increase their life-span. As such this work describes different transformer oils, what advantages and disadvantages they have compared to mineral oils, what properties they have and in what way they’re less harmful for the environment. HVDC units transform high voltages from Alternating Current to Direct Current to lessen the resistive losses and energy losses which lead to a cleaner environment. The theory examination of the transformer is the basis for the formation of a lab for educational use, among others in a course about electrical power that’s included in Bachelor of Science in Electrical Engineering at KTH.
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Forward Osmosis Application in Manufacturing Industries: A Short ReviewHaupt, Anita, Lerch, André 13 December 2018 (has links)
Forward osmosis (FO) is a membrane technology that uses the osmotic pressure difference to treat two fluids at a time giving the opportunity for an energy-efficient water and wastewater treatment. Various applications are possible; one of them is the application in industrial water management. In this review paper, the basic principle of FO is explained and the state-of-the-art regarding FO application in manufacturing industries is described. Examples of FO application were found for food and beverage industry, chemical industry, pharmaceutical industry, coal processing, micro algae cultivation, textile industry, pulp and paper industry, electronic industry, and car manufacturing. FO publications were also found about heavy metal elimination and cooling water treatment. However, so far FO was applied in lab-scale experiments only. The up-scaling on pilot- or full-scale will be the essential next step. Long-term fouling behavior, membrane cleaning methods, and operation procedures are essential points that need to be further investigated. Moreover, energetic and economic evaluations need to be performed before full-scale FO can be implemented in industries.
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Use of Bio-Product/Phase Change Material Composite in the Building Envelope for Building Thermal Control and Energy SavingsBoozula, Aravind Reddy 08 1900 (has links)
This research investigates the bio-products/phase change material (PCM) composites for the building envelope application. Bio-products, such as wood and herb, are porous medium, which can be applied in the building envelope for thermal insulation purpose. PCM is infiltrated into the bio-product (porous medium) to form a composite material. The PCM can absorb/release large amount of latent heat of fusion from/to the building environment during the melting/solidification process. Hence, the PCM-based composite material in the building envelope can efficiently adjust the building interior temperature by utilizing the phase change process, which improves the thermal insulation, and therefore, reduces the load on the HVAC system. Paraffin wax was considered as the PCM in the current studies. The building energy savings were investigated by comparing the composite building envelope material with the conventional material in a unique Zero-Energy (ZØE) Research Lab building at University of North Texas (UNT) through building energy simulation programs (i.e., eQUEST and EnergyPlus). The exact climatic conditions of the local area (Denton, Texas) were used as the input values in the simulations. It was found that the EnergyPlus building simulation program was more suitable for the PCM based building envelope using the latent heat property. Therefore, based on the EnergyPlus simulations, when the conventional structure insulated panel (SIP) in the roof and wall structures were replaced by the herb panel or herb/PCM composite, it was found that around 16.0% of energy savings in heating load and 11.0% in cooling load were obtained by using PCM in the bio-product porous medium.
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DEVELOPMENT, DESIGN, AND CONSTRUCTION OF A HUMAN-BUILDING INTERACTIONS LABORATORYSourabh Deepak Yadav (12224741) 20 April 2022 (has links)
<div>The evolution of existing building construction is envisioned as modular construction. Instead of on-site construction, buildings can be assembled on-site using prefabricated modular elements. These modular elements could integrate intelligent building technologies to enable autonomous, occupant responsive, scalable, cost-effective, and sustainable features. On-site assembly of modular construction elements would offer better quality control, decrease material waste and resources, with more predictable schedules. These building elements would allow more cost-effective integration of new intelligent sensors, adaptive interfaces, renewable energy and energy recovery technologies, comfort delivery, and resiliency technologies, making high-performance buildings more affordable. To explore and evaluate these modular and intelligent comfort delivery concepts and advanced approaches for interaction with occupants, a new Human-Building Interactions Laboratory (HBIL) has been designed and is under development. The facility has a modular construction layout with thermally active panels, and the interior surface temperature of each panel can be individually controlled using a hydronic system. Such configuration allows us to emulate different climate zones and building type conditions and perform studies such as the effect of different kinds of active building surfaces on thermal comfort, localized comfort delivery, and occupant comfort control. Moreover, each panel is reconfigurable to investigate different interior surface treatments for thermal, visual, and acoustic comfort conditions. <br></div><div>In this MS thesis work, the overall design approach of the facility is presented. Development, experimental investigation of thermal performance, and aligned design modifications of a prototype thermo-active wall panel are explained in detail. Detailed development of a 1-D transient numerical model for the prototype wall panel and its tuning and validation are also presented. Furthermore, the design and installation plan of the hydronic system for the HBIL facility are also presented with an initial commissioning plan.</div>
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