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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.
1

An investigation of the National Building Regulations to promote uniformity and sustainability in the South African built environment

Laubscher, Jacques 12 October 2011 (has links)
The study investigates two aspects that arise when an application is made for building plan approval to the Building Control Officer (BCO) in the Department of Building Control at a local authority (LA). Firstly, the uniform application of the minimum requirements for building plan approval is studied. Secondly, while keeping the original goal of the National Building Regulations (NBR) in mind, the inclusion of passive design requirements is considered as part of the minimum requirements. In the Republic of South Africa (South Africa), the National Building Regulations and Building Standards Act, 1977 (Act 103 of 1977) determines the minimum requirements of any building. Although the NBR are in the process of being rewritten, the amended 1990 version is still being used. On 15 June 2010, the South African National Standard (SANS) 10400-XA: The Application of the National Building Regulations Part X: Environmental Sustainability Section A: Energy Usage in Buildings, was published for public comment. However, the current version of the NBR does not address sustainability. Therefore, it is argued that the planning and erection of structures within the South African built environment do not currently conform to any minimum sustainability requirements. A series of ‘Deemed-to-Satisfy Rules’ constitutes an integral part of the NBR. Should a development in the built environment comply with these prerequisites, it is observing the statutory requirements of Act 103 of 1977. The regulations are implemented by the Department of Building Control of the different LAs (or municipalities). Act 103 of 1977 also prescribes the appointment, qualifications and functions of the BCO who should head the department. However, it is the LA’s responsibility to appoint the BCO. An LA’s Department of Building Control uses guidelines (as determined by Act 103 of 1977) to approve applications for new buildings and alterations to existing ones. A series of prescribed inspections should be conducted during the construction phase of a building. Before a building can be used for its intended purpose, the BCO has to sign a Certificate of Occupancy. Although the NBR provide prescriptions, the requirements are implemented in different ways by the various LAs. After determining the origin and examining the goals and implementation methods of Act 103 of 1977 and its Regulations (together with the Code of Application (SANS 10400:1990)), this study demonstrates that the current edition of the NBR is not uniformly implemented in the Republic of South Africa. Additionally, the study links the original goal of the NBR to limit inflationary tendencies with current practice to use passive design principles to combat building operation costs. Lastly, a pro forma application form is included as an addendum (although it is not officially part of the study). This proposed pro forma could assist in the uniform implementation of NBR, while at the same time promoting sustainability. / Thesis (PhD)--University of Pretoria, 2011. / Architecture / unrestricted
2

Optimering av en intern datorplattform : En utredning åt Byggtec Gävleborg AB

Jörnelind, Johan January 2017 (has links)
Syftet med uppsatsen är att ta fram en mall för intern dokumenthantering och projektstyrning åt byggföretaget Byggtec Gävleborg AB. För att komma fram till resultatet har jag till använt mig av intervjuer av olika tjänstemän på Byggtec. Jag har även gjort litteraturstudier genom 4 tidskrifter med inriktning mot byggbranschen, samt studerat liknande system som redan finns på marknaden. Totalt så intervjuades 3 byggplatschefer samt den ekonomiansvarige och VD:n, detta gav en god uppfattning om vilka områden som borde täckas upp på plattformen, det gav även en bild av hur de vill att arbetet med plattformen ska utföras. Intervjuerna som gjordes handlade om de olika byggplatschefernas arbetssätt i dagsläget, samt hur de vill att plattformen ska byggas upp och hur de vill att den ska användas. Rapporten är avgränsad till att tillgodose Byggtec Gävleborg ABs behov då det är för dem studien är gjord, men trots att den är avgränsad till Byggtec så fungerar upplägget lika bra även åt andra byggföretag. Detta resulterade i en mall som lämpar sig bra att spara de viktigaste och mest användbara dokumenten under ett byggprojekt i. Mallen innehåller även de viktigaste dokument och handlingar som kan tänkas användas i framtida bruk. / The purpose with this essay is to obtain a template for internal document management and project control for the company Byggtec Gävleborg AB. To achieve the results I mostly have used interviews of different officials at Byggtec. Other methods that has been used is literature studies through different magazines and also studying similar systems that are already on the market. Totally 3 construction site managers, the financial officer and the CEO were interviewed. This gave a good perception of what subjects that should be covered by the platform. It also gave a picture of how they wanted the work with the platform would be done. The interviews who were held was how the construction site managers work today, how they want the platform to be constructed and how they want it to be used. The report is limited to meet the requirements of Byggtec Gävleborg AB. It is for them the report has been done. Although it is limited for them the report layout would be suitable for any building company. This gave as result a template useable to save the most important documents during a constructing project. The template also contains the most important documents which may be used for future use. / <p>Betyg 170707, H14.</p>
3

Algorithms and Simulation Framework for Residential Demand Response

Adhikari, Rajendra 11 February 2019 (has links)
An electric power system is a complex network consisting of a large number of power generators and consumers interconnected by transmission and distribution lines. One remarkable thing about the electric grid is that there has to be a continuous balance between the amount of electricity generated and consumed at all times. Maintaining this balance is critical for the stable operation of the grid and this task is achieved in the long term, short term and real-time by operating a three-tier wholesale electricity market consisting of the capacity market, the energy market and the ancillary services market respectively. For a demand resource to participate in the energy and the capacity markets, it needs to be able to reduce the power consumption on-demand, whereas to participate in the ancillary services market, the power consumption of the demand resource needs to be varied continuously following the regulation signal sent by the grid operator. This act of changing the demand to help maintain energy balance is called demand response (DR). The dissertation presents novel algorithms and tools to enable residential buildings to participate as demand resources on such markets to provide DR. Residential sector consumes 37% of the total U.S. electricity consumption and a recent consumer survey showed that 88% of consumers are either eager or supportive of advanced technologies for energy efficiency, including demand response. This indicates that residential sector is a very good target for DR. Two broad solutions for residential DR are presented. The first is a set of efficient algorithms that intelligently controls the customers' heating, ventilating and air conditioning (HVAC) devices for providing DR services to the grid. The second solution is an extensible residential demand response simulation framework that can help evaluate and experiment with different residential demand response algorithms. One of the algorithms presented in this dissertation is to reduce the aggregated demand of a set of HVACs during a DR event while respecting the customers' comfort requirements. The algorithm is shown to be efficient, simple to implement and is proven to be optimal. The second algorithm helps provide the regulation DR while honoring customer comfort requirements. The algorithm is efficient, simple to implement and is shown to perform well in a range of real-world situations. A case study is presented estimating the monetary benefit that can be obtained by implementing the algorithm in a cluster of 100 typical homes and shows promising result. Finally, the dissertation presents the design of a python-based object-oriented residential DR simulation framework which is easy to extend as needed. The framework supports simulation of thermal dynamics of a residential building and supports house hold appliances such as HVAC, water heater, clothes washer/dryer and dish washer. A case study showing the application of the simulation framework for various DR implementation is presented, which shows that the simulation framework performs well and can be a useful tool for future research in residential DR. / PHD / The total power generation and consumption has to always match in the electric grid. When there is a mismatch because the generation is less than the load, the match can be restored either by increasing the generation or by decreasing the load. Often, during system stress conditions, it is cheaper to decrease certain loads than to increase generation, and this method of achieving power balance is called demand response (DR). Residential sector consumes 37% of the total U.S. electricity consumption and is largely unexplored for demand response purpose, so the focus of the dissertation is on providing solutions to enable residential houses to provide demand response services. This dissertation presents two broad solutions. The first is a set of efficient algorithms that intelligently controls the customers’ heating, ventilating and air conditioning (HVAC) devices for providing DR services to the grid while keeping their comfort in mind. The second solution is a simulation software that can help evaluate and experiment with different residential demand response algorithms. The first algorithm is for reducing the collective power consumption of an aggregation of residential HVAC, whereas the second algorithm is for making the collective power follow a signal sent by the grid operators. It is shown that the algorithms presented can intelligently control the HVAC devices such that DR services can be provided to the grid while ensuring that the temperatures of the houses remain within comfortable range. The algorithms can enable demand response service providers to tap into the residential demand response market and earn revenue, while the simulation software can be valuable for future research in this area. The simulation software is simple to use and is designed with extensibility in mind, so adding new features is easy. The software is shown to work well for studying residential building control for demand response purpose and can be a useful tool for future research in residential DR.
4

Development of robust building energy demand-side control strategy under uncertainty

Kim, Sean Hay 25 May 2011 (has links)
The potential of carbon emission regulations applied to an individual building will encourage building owners to purchase utility-provided green power or to employ onsite renewable energy generation. As both cases are based on intermittent renewable energy sources, demand side control is a fundamental precondition for maximizing the effectiveness of using renewable energy sources. Such control leads to a reduction in peak demand and/or in energy demand variability, therefore, such reduction in the demand profile eventually enhances the efficiency of an erratic supply of renewable energy. The combined operation of active thermal energy storage and passive building thermal mass has shown substantial improvement in demand-side control performance when compared to current state-of-the-art demand-side control measures. Specifically, "model-based" optimal control for this operation has the potential to significantly increase performance and bring economic advantages. However, due to the uncertainty in certain operating conditions in the field its control effectiveness could be diminished and/or seriously damaged, which results in poor performance. This dissertation pursues improvements of current demand-side controls under uncertainty by proposing a robust supervisory demand-side control strategy that is designed to be immune from uncertainty and perform consistently under uncertain conditions. Uniqueness and superiority of the proposed robust demand-side controls are found as below: a. It is developed based on fundamental studies about uncertainty and a systematic approach to uncertainty analysis. b. It reduces variability of performance under varied conditions, and thus avoids the worst case scenario. c. It is reactive in cases of critical "discrepancies" observed caused by the unpredictable uncertainty that typically scenario uncertainty imposes, and thus it increases control efficiency. This is obtainable by means of i) multi-source composition of weather forecasts including both historical archive and online sources and ii) adaptive Multiple model-based controls (MMC) to mitigate detrimental impacts of varying scenario uncertainties. The proposed robust demand-side control strategy verifies its outstanding demand-side control performance in varied and non-indigenous conditions compared to the existing control strategies including deterministic optimal controls. This result reemphasizes importance of the demand-side control for a building in the global carbon economy. It also demonstrates a capability of risk management of the proposed robust demand-side controls in highly uncertain situations, which eventually attains the maximum benefit in both theoretical and practical perspectives.
5

Návrh a tvorba ukázkových panelů se systémovou instalací Inels / Design and production of sample panels with system installation Inels

Steidl, Jaromír January 2010 (has links)
Diploma thesis deals with the problems of system installations. The system installation is presented as an installation, where the light switch does not serve for interrupt a power circuit, but it serves as a sensor, which directs the status change of actuator, that makes the own manipulation with a power circuit. In the first chapter the diploma thesis presents the history of the system installation development depending on the demand for the system regulation in buildings centrally and complexly. There are also summarize advantages and disadvantages of installations, which are used in these days. In the second chapter, the system installations are devided into centralized and decentralized systems. The centralized systems are constructionally simpler as well the communication, but the whole system is more inclinable to fail. The decentralized systems are more complicated, more expensive, but more reliable and they have also potentiality to extand. Two decentralized systems, nowadays the most used, are further presented – KNX and LonWorks. They are used especially for the administration buildings control. Then the diploma thesis presents both some systems, which are used abroad, and the situation at the Czech market, whereas there is described the system INELS, which is made by Elko ep. Limited Company. The goal of the thesis, which is mentioned in the third chapter, is to present the system installations, design a panel with this installation including the panel´s handmade, and then on this panel demonstrate the panel´s using for education in laboratory practices. The fourth chapter discusses the author´s characterization of the panel´s concept – there is described the graphical concept of the panel, used units and their integrations. By all of used units their functions on the panel are described. In the last but one chapter, there are mentioned the practical applications, which the panel serves, and there are also described the concepts of laboratory tasks for education of the fundamental configuration and possibilities of the system installation INELS. The chapter also engage in the configuration of the system for the panel, which presents control elements in one room via the system installation INELS. This configuration serves for the presentation of the educational panel. The conclusion is dedicated to the summary of the mentioned problems.
6

Deep reinforcement learning for automated building climate control

Snällfot, Erik, Hörnberg, Martin January 2024 (has links)
The building sector is the single largest contributor to greenhouse gas emissions, making it a natural focal point for reducing energy consumption. More efficient use of energy is also becoming increasingly important for property managers as global energy prices are skyrocketing. This report is conducted on behalf of Sustainable Intelligence, a Swedish company that specializes in building automation solutions. It investigates whether deep reinforcement learning (DLR) algorithms can be implemented in a building control environment, if it can be more effective than traditional solutions, and if it can be achieved in reasonable time. The algorithms that were tested were Deep Deterministic Policy Gradient, DDPG, and Proximal Policy Optimization, PPO. They were implemented in a simulated BOPTEST environment in Brussels, Belgium, along with a traditional heating curve and a PI-controller for benchmarks. DDPG never converged, but PPO managed to reduce energy consumption compared to the best benchmark, while only having slightly worse thermal discomfort. The results indicate that DRL algorithms can be implemented in a building environment and reduce green house gas emissions in a reasonable training time. This might especially be interesting in a complex building where DRL can adapt and scale better than traditional solutions. Further research along with implementations on physical buildings need to be done in order to determine if DRL is the superior option.
7

Semi-active Control Of Earthquake Induced Vibrations In Structures Using MR Dampers : Algorithm Development, Experimental Verification And Benchmark Applications

Ali, Shaik Faruque 07 1900 (has links)
As Civil Engineering structures, e.g., tall buildings, long span bridges, deep water offshore platforms, nuclear power plants, etc., have become more costly, complex and serve more critical functions, the consequences of their failure are catastrophic. Therefore, the protection of these structures against damage induced by large environmental loads, e.g., earthquakes, strong wind gusts and waves, etc., is without doubt, a worldwide priority. However, structures cannot be designed to withstand all possible external loads and some extraordinary loading episodes do occur, leading to damage or even failure of the structure. Protection of a structure against hazards can be achieved by various means such as modifying structural rigidities, increasing structural damping, and by attaching external devices, known as control devices. Control devices can be deployed either to isolate the structure from external excitation or to absorb input seismic energy to the structure (absorber) so as to mitigate vibration in the primary structure. Seismic base isolation is one such mechanism which isolates a structure from harmful ground excitations. Seismic base isolation is a widely accepted and implemented structural control mechanism due to its robustness and ease in deployment. Following the Northridge earthquake (1994), and Kobe earthquake (1995), the interest of structural engineers in understanding near-source ground motions has enhanced. Documents published after these earthquakes emphasized the issue of large base displacements because of the use of none or little isolation damping (of viscous type only) prior to these events. More recent studies have investigated analytically and experimentally, the efficiency of various dissipative mechanisms to protect seismic isolated structures from recorded near-source long period, pulse-type, high velocity ground motions. Consequently, hybrid isolation systems, seismic base isolation supplemented with damping mechanisms, have become the focus of current research trend in structural vibration control. Hybrid base isolation system incorporating passive supplemental damping devices like, viscous fluid dampers, etc., performs satisfactorily in minimizing isolator displacement but at the same time increases superstructure acceleration response. Furthermore, the passive system can be tuned to a particular frequency range and its performance decreases for frequencies of excitation outside the tunning bandwidth. In such a scenario, active control devices in addition to base isolation mechanism provide better performance in reducing base displacement and superstructure acceleration for a broad range of excitation frequencies. Tremendous power requirement and the possibility of power failure during seismic hazards restrict the usage of active systems as a supplemental device. Semi-active devices provide the robustness of passive devices and adaptive nature of active devices. These characteristics make them better suited for structural control applications. The recent focus is on the development of magnetorheological (MR) dampers as semi-active device for structural vibration control applications. MR dampers provide hysteretic damping and can operate with battery power. The thrust of this thesis is on developing a hybrid base isolation mechanism using MR dampers as a supplemental damping device. The use of MR damper as a semi-active device involves two steps; development of a model to describe the MR damper hysteretic behaviour; development of a proper nonlinear control algorithm to monitor MR damper current / voltage supply. Existing parametric models of MR damper hysteretic behaviour, e.g., Bouc-Wen model, fail to consider the effect of amplitude and frequency of excitation on the device. Recently reported literature has demonstrated the necessity of incorporating amplitude and frequency dependence of MR damper models. The current/voltage supply as the input variable to the MR damper restricts the direct use of any control algorithms developed for active control of structures. The force predicted by the available control algorithms should be mapped to equivalent current/voltage and then to be fed into the damper. Available semi-active algorithms in the literature used ‘on-off’ or ‘bang-bang’ strategy for MR applications due to nonlinear current/voltage-force relation of MR damper. The ‘on-off’ nature of these algorithms neither provides smooth change in MR damper current/voltage input nor considers all possible current/ voltage values within its minimum to maximum range. Secondly, these algorithms fail to consider the effect of the MR damper applied and commanded current/voltage dynamics. The thrust of this dissertation is to develop semi-active control algorithms to monitor MR damper supply current/voltage. The study develops a Bouc-Wen based model to characterize the MR damper hysteretic phenomenon. Experimental results and modeling details have been documented. A fuzzy based intelligent control and two model-based nonlinear control algorithms based on optimal dynamic inversion and integral backstepping have been developed. Performance of the fuzzy logic based intelligent control has been explored using experimental investigation on a three storey base isolated building. Further the application of the proposed controllers on a benchmark building; a benchmark highway bridge and a stay cable vibration reduction have been discussed. Experimental study has revealed that the performance of optimal FLC is better than manually designed FLC in terms of reducing base displacement and storey accelerations. The performance of both the FLCs (simple FLC and genetic algorithm based optimal FLC) is better than ‘passive-off’ (zero ampere current supply) and ‘passive-on’ (one ampere current supply) condition of MR damper applications. The ‘passive-off’ results have shown higher base displacements with lower storey accelerations, whereas, the ‘passive-on’ results have reduced base displacement to the least but at the same time increased the storey acceleration too much. The FLC monitored MR damper show a compromise between the two passive conditions. Analytical results confirm these observations. Numerical simulations of the base isolated building with the two model based MR damper control algorithms developed have shown a better performance over FLC and widely used clipped optimal algorithms. The applications of the proposed semi-active control algorithms (FLC, dynamic inversion and integral backstepping) have shown better performance in comparison to that of control algorithms provided with the benchmark studies.
8

Sběr MaR dat / Collection of measurement and control data

Podolský, Ondřej January 2017 (has links)
The semester thesis outlines the idea of the concept of intelligent building and related technologies. The first section describes the devices used in the field of intelligent installations in particular selected communication protocols and bus. In the next section there are some examples of systems from different manufacturer and the most detailed herein descripted system is Honeywell’s system built on NiagaraAX Framework because the practical part of the work is implemented using this system. The last part describes creation process of data visualization and storage obtained from intelligent building of Faculty of Electrical Engineering and Communication.
9

Deep Reinforcement Learning for Temperature Control in Buildings and Adversarial Attacks

Ammouri, Kevin January 2021 (has links)
Heating, Ventilation and Air Conditioning (HVAC) systems in buildings are energy consuming and traditional methods used for building control results in energy losses. The methods cannot account for non-linear dependencies in the thermal behaviour. Deep Reinforcement Learning (DRL) is a powerful method for reaching optimal control in many different control environments. DRL utilizes neural networks to approximate the optimal actions to take given that the system is in a given state. Therefore, DRL is a promising method for building control and this fact is highlighted by several studies. However, neural network polices are known to be vulnerable to adversarial attacks, which are small, indistinguishable changes to the input, which make the network choose a sub-optimal action. Two of the main approaches to attack DRL policies are: (1) the Fast Gradient Sign Method, which uses the gradients of the control agent’s network to conduct the attack; (2) to train a a DRL-agent with the goal to minimize performance of control agents. The aim of this thesis is to investigate different strategies for solving the building control problem with DRL using the building simulator IDA ICE. This thesis is also going to use the concept of adversarial machine learning by applying the attacks on the agents controlling the temperature inside the building. We first built a DRL architecture to learn how to efficiently control temperature in a building. Experiments demonstrate that exploration of the agent plays a crucial role in the training of the building control agent, and one needs to fine-tune the exploration strategy in order to achieve satisfactory performance. Finally, we tested the susceptibility of the trained DRL controllers to adversarial attacks. These tests showed, on average, that attacks trained using DRL methods have a larger impact on building control than those using FGSM, while random perturbation have almost null impact. / Ventilationssystem i byggnader är energiförbrukande och traditionella metoder som används för byggnadskontroll resulterar i förlust av energisparande. Dessa metoder kan inte ta hänsyn till icke-linjära beroenden i termisk beteenden. Djup förstärkande inlärning (DRL) är en kraftfull metod för att uppnå optimal kontroll i många kontrollmiljöer. DRL använder sig av neurala nätverk för att approximera optimala val som kan tas givet att systemet befinner sig i en viss stadie. Därför är DRL en lovande metod för byggnadskontroll och detta faktumet är markerat av flera studier. Likväl, neurala nätverk i allmänhet är kända för att vara svaga mot adversarial attacker, vilket är små ändringar i inmatningen, som gör att neurala nätverket väljer en åtgärd som är suboptimal. Syftet med denna anvhandling är att undersöka olika strategier för att lösa byggnadskontroll-problemet med DRL genom att använda sig av byggnadssimulatorn IDA ICE. Denna avhandling kommer också att använda konceptet av adversarial machine learning för att attackera agenterna som kontrollerar temperaturen i byggnaden. Det finns två olika sätt att attackera neurala nätverk: (1) Fast Gradient Sign Method, som använder gradienterna av kontrollagentens nätverk för att utföra sin attack; (2) träna en inlärningsagent med DRL med målet att minimera kontrollagenternas prestanda. Först byggde vi en DRL-arkitektur som lärde sig kontrollera temperaturen i en byggad. Experimenten visar att utforskning av agenten är en grundläggande faktor för träningen av kontrollagenten och man måste finjustera utforskningen av agenten för att nå tillfredsställande prestanda. Slutligen testade vi känsligheten av de tränade DRL-agenterna till adversarial attacker. Dessa test visade att i genomsnitt har det större påverkan på kontrollagenterna att använda DRL metoder än att använda sig av FGSM medans att attackera helt slumpmässigt har nästan ingen påverkan.
10

Pension Dolní Morava - vybrané části stavebně technologického projektu / Boarding house Dolní Morava - selected parts of the construction technology plan

Šušlík, Marek January 2018 (has links)
The content of the diploma thesis are selected parts of technological project of new building boarding house in Dolní Morava. The diploma thesis includes technical regulation for ground works and ceiling construction. The technological regulations are complemented by design of machine assembly, site facilities and control and test plan. There are the time schedule, suggestion of the realization of the main stages of its construction including suggestion of main construction mechanism and budget of new building.

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