338 research outputs found
A Meaning of Baroque in terms of Space Syntax
No full textA city is a spatial system that is generated in the process of searching for an ideal form. From the structure of a city, we can find paradigms of the past in which worldviews of the society are instilled. Baroque, to be studied in this paper, is interpreted as a change from ′limitation′ to ′infinity′. There are many studies that investigated Baroque but they see the change from a single viewpoint of either cosmology or practicality. The purpose of this study is, therefore, to combine these two viewpoints for a comprehensive understanding of what paradigm has formed Baroque cities. Practicality is revealed by means of Space Syntax and our new concept, Urban Entropy Coefficient (: UEC), which is then related to cosmology. We conclude that the intention of Baroque was to configure a Multi-Center layout for the dynamic function of the city
Fuzzy Layout Planner: A simple layout planning tool for early stages of design
No full textThis study presents a digital architectural design tool named \u93Fuzzy Layout Planner\u94 that helps architects create two dimensional sketchy footprints for their design. The purpose of the tool is to extend limits of early design thinking. It uses fuzzy modeling techniques to adapt the ambiguous design phase. There are several commands in this digital tool to generate and modify layouts. Users can create, move, combine sketchy bubbles to form bigger footprints and see them in action dynamically. The tool offers a manual creation process
Logic synthesis for automatic layout
No full textISBN: 0818628456The author present an attempt to automate the design of complex modules using a synthesis tool. They aim at generating automatically and directly the layout of a module using complex MOS cells from a behavioural specification. The re-design of the library elements for a new technology would then be replaced by only some changes in the technology files. The two main steps presented in this paper are the decomposition of the initial netlist into complex MOS cells with adequate characteristics and the layout generation for the complex cells
Offshore Wind Farm Layout Optimisation: To provide insight in what can be expected from offshore wind farm layout optimisation
No full textThe potential gain in energy production and profit by improving the placements of turbines within a wind farm is driving interest. However, finding the optimal placements provides a complex problem. A large number of inter-dependent design variables create a design space that is difficult to solve. Therefore there is much attention for offshore wind farm layout optimisation (OWFLO) in practice and literature. Most of the research is done in selecting and creating the best optimisation algorithms, wake models and cost models.This is not yet another study into better modelling or optimiser selection for OWFLO. Instead, this study aims to provide insight into what performance can be expected from OWFLO and to know when further optimising is not justifiable anymore. The study consists of three parts. All three parts make use of a referent. A referent can be considered a close representation of reality, obtained by a best-practice implementation of the optimisation problem and its associated models. It is assumed that the referent has the same characteristics as reality and that deviations of other implementations of OWFLO from the referent are representative of their deviations from the true optimisation problem.\\In this study, the referent is defined by, amongst others, the use of the Bastankhah and Porté-Agel Gaussian wake model, a 12 sector wind rose with a Weibull distribution per sector and the gradient-free covariance matrix adaptation evolution strategy. The referent is used to maximise annual energy production (AEP). The first part uses the referent to find and understand the characteristics of the OWFLO problem. Wind farms with 9, 25 and 64 turbines have been optimised 100 times with the referent. The results show a small spread in the performance of the found optimised layouts, indicating that many local optima exist with similar performances in an OWFLO problem. The spread between the highest and lowest found performance decreases with increasing numbers of turbines. A special form of the response surface is used to visualise the response surface. The visualised response surfaces, with only two design variables, showed that the wakes of the turbines created multiple local optima.The second part compares performances from optimised layouts with 25 turbines resulting from optimisations with alternative implementation choices, evaluated by the referent model. The performances are represented in boxplots for 100 optima each. The boxplots show that the influence of alternative implementation choices depends on the slightly different locations of the local optima in the design space and the roughness of the response surface they create. The influence of the shifts in locations of the local optima on the performance turned out to be minimal. An increase in the roughness of the response surface meant an increase in the spread of the performances. The difference in performance resulting from the alternative optimisers indicates that improvement of a state-of-the-art optimiser is not expected to lead to much better results. The third part explores the need for improvement of the analysis by adding a phenomena currently not considered in OWFLO. The influence of neighbouring wind farms on layout optimisation without including atmospheric stability is explored. Three cases have been defined to show the influence of neighbouring wind farms on layout optimisation. It is concluded that adding neighbouring wind farms for accurate energy yield assessments is necessary. However, for layout optimisation, the benefit of including neighbouring wind farms is not evident.Electrical Engineering | Sustainable Energy Technolog
Automated car interior layout design based on user activities
No full textThe evolution of the automated driving industry liberates users from driving tasks, thus creating more time for Non-Driving-Related activities (NDRAs), thereby transforming the car from a mere mode of transport to a mobile activity platform. This shift presents two main challenges: predicting the type of activities passengers will engage in within the automated cars and adapting the car’s interior design to accommodate these activities. This project tackles these challenges with a focus on comfort, ergonomics, and user activity, promising valuable insights for the interior design of future automated vehicles.A rigorous review of literature spanning 2014 to 2023 was conducted, with a focus on NDRAs in automated vehicles. The review retrieved 2315 papers from various databases, from which 47 articles encapsulating 66 cases and 50 types of activities were selected based on strict eligibility criteria. These activities were then categorized into 13 clusters, with the top five being Entertainment and online activities, Work and productivity, Interpersonal communication and interaction, Sleep and relaxation, and Observation and monitoring.An exploratory experiment was conducted within a simulated automated vehicle environment to study the ergonomic and spatial needs of five significant NDRAs. These activities were the most representative of each of the five main clusters: talking to passengers, looking out the window, working on a computer, sleeping, and using an iPad for entertainment. This investigation filled a crucial research gap, providing valuable insights for designing more ergonomic and comfortable interiors for future automated vehicles.The project further leveraged 3D modeling and Augmented Reality (AR) technologies to analysis the spatial requirements of users engaging in the identified NDRAs within a Range Rover Evoque. The research indicates that the current interior design of the Range Rover Evoque can accommodate average-sized (P50) users performing 5 major Non-Driving-Related activities at small or medium comfort joint angles, yet struggles to support larger comfortable joint angles, particularly for activities such as sleeping, entertainment, or work. The results suggest a future design could include slimmer seats and dashboards and potentially transition from a four-seater layout to a two or three-seater layout to provide more space for users for activities.After evaluation of initial concepts for future automated vehicle interior design, I have combined their strengths and minimized their shortcomings to develop a final iteration. This design focuses on flexible space allocation by incorporating a slim dashboard and thinner seats and can shift between a standard four-seat configuration to a 2 or 3-seater layout, and include independent seats, and an adjustable table to cater to various user needs, setting the stage for the future of comfortable Non-Driving-Related activities within vehicles.In conclusion, this project integrates theoretical and practical approaches, focusing on user activities and comfort in automated vehicles. The study leaves out considerations of commercial viability, manufacturing, and socio-cultural aspects. Future improvements should include these factors and align design with commercial and manufacturing realities.Integrated Product Desig
Wingtip-Mounted Propellers: Aerodynamic Analysis of Interaction Effects and Comparison with Conventional Layout
No full textWingtip-mounted propellers installed in a tractor configuration can decrease the wing induced drag by attenuating the wingtip vortex by the propeller slipstream. This paper presents an aerodynamic analysis of the propeller-wing interaction effects for the wingtip-mounted propeller configuration, including a comparison with a conventional configuration with the propeller mounted on the inboard part of the wing. Measurements were taken in a low-speed wind tunnel at Delft University of Technology, with two wing models and a low-speed propeller. Particle-image-velocimetry measurements downstream of a symmetric wing with integrated flap highlighted the swirl reductions characteristic of the wingtip-mounted propeller due to wingtip-vortex attenuation and swirl recovery. External-balance and surface-pressure measurements confirmed that this led to an induced-drag reduction with inboard-up propeller rotation. In a direct comparison with a conventional propeller-wing layout, the wingtip-mounted configuration showed a drag reduction of around 15% at a lift coefficient of 0.5 and a thrust coefficient of 0.12. This aerodynamic benefit increased upon increasing the wing lift coefficient and propeller thrust setting. An analysis of the wing performance showed that the aerodynamic benefit of the wingtip-mounted propeller was due to an increase of the wing's effective span-efficiency parameter.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Flight Performance and Propulsio
Modular impulsive green-monopropellant propulsion system for micro/nano satellites high-thrust orbital maneuvers (MIMPS-G)
No full textInnovation in small-satellite modern space missions and applications require propulsion capabilities to enable active operations in orbit, such as formation flying, rendezvous operations, orbital altitude & inclination changes, and orbital transfers,– generally, operations demanding high-thrust impulsive maneuvers. In addition, Green-monopropellants are current state-of-the-art of liquid propellants for small satellites space propulsion due to their safety, stability, storability, relative design simplicity, and high performance. These facts were the motive behind the design of the Modular Impulsive Propulsion System– namely MIMPS-G – that utilizes Green-monopropellants and is a prospect solution for micro- and nano- spacecraft, particularly CubeSats, requiring a modular propulsion system for high-thrust impulsive orbital maneuvers. The baseline design is a standard 1U that can be expanded depending on the spacecraft size, required thrust level, and mission’s ΔV requirements. System analysis and preliminary design of MIMPS-G are discussed, and system architecture is presented. Different pressurization-systems are investigated – conventional and unconventional relative to small-satellites – emphasizing on autogenous-pressurization system utilizing micro electric pump, since the choice of the pressurization-system will further affect the propulsion system overall performance, onboard power consumption, and the spacecraft size optimization. A tradeoff study with regards to the performance and characteristics of suitable monopropellants, to be utilized by MIMPS-G, is carried out to give insights for system design and architecture possibilities, as well as future studies concerned with monopropellant propulsion systems for various classes of space propulsion. Finally, candidate propulsion system utilizing a 0.5 N thruster – designated as MIMPS-G500mN – is introduced elaborating system’s architecture, analysis, design, and CAD models. MIMPS-G500mN offers total impulse 퐼푡표푡 ≅ 850 to 1350 N.s per 1U or >3000 푁.푠 per 2U expanded-layout depending on used propellant, which makes the latter a modular expandable propulsion system suitable for Lunar missions. Comparative results of the propulsion system properties using different monopropellants are tabulated – focusing on alternatives for the highly stable Hydroxyl-ammonium nitrate (HAN-) based monopropellant AF-M315E, that is the state-of-art of green-monopropellants.Virtual/online event due to COVID-19 accepted author manuscriptSpace Systems Egineerin
David and the vegetable factory: A Two-stage Optimization Model for Generating a Vegetable Factory's Facility Layout Using the Gradient Descent Approach
No full textIn this thesis a two-stage model is proposed, combining the idea of a two-stage model from Anjos and Vieira [1] with a gradient descent approach, much like proposed in Sikaroudi and Shahanaghi [42], in order to solve the facility layout problem for problems consisting of 8 and 12 departments . This method was chosen after analyzing the criteria for a vegetable processing factory and combining this with a literature research to previous methods applied to solve these "facility layout problems". The gradient descent approach uses the partial derivatives of a multi-variable objective, the flow-cost, in order to get a vector which is the direction of greatest descent. Computing this vector for all departments and then moving them creates an iterative improving loop. In addition to the gradient descent approach a swapping procedure and a shooting procedure is introduced in order to reduce the effect of random starting position. From the result of the first-stage model, relative location constraints are extracted to be used in the second-stage model, a linear constraint programming solver capable of running optimizations by google or-tools [36], to greatly reduce the solution space. The proposed method was tested on two toy-problems from Tam and Li [44] and compared to results existing in literature. Additionally, the effect of including a first-stage model was tested as well. When looking directly at the results, the proposed method is consistent and shows good results. Especially the inclusion of the first-stage model helps finding better solutions. Compared to other results found in the literature, the method shows slightly less good results based purely on the objective value. However, the final layouts found in this thesis are more compact.Architecture, Urbanism and Building Sciences | Building Technolog
Evaluation and analysis of impact of subsidies on small scale renewable energy technologies dissemination: a case study of Nepal
No full textThe report has analysed the status of rural electrification using renewable energy technologies (RETs) and the current subsidy delivery modality of RETs in Nepal. As the Government of Nepal is subsidizing small scale renewable energy projects, it is important to evaluate and analyse the programme to make sure that a programme is running in an effective and efficient way while reaching the target group.
During the course of the research, primary information collected from the field has been compiled using appropriate tools/software (such as MS Office) and analyzed. Different sets of questionnaires were prepared, targeting different personnel ranging from the users’ level to the government policy level. The field survey methods include field observations of RETs installations and operations along with interviews with selected users on a random sampling basis to identify barriers to subsidy delivery and possible measures to overcome these barriers; to determine user satisfaction level and time period for subsidy delivery mechanisms.
The report started with the country background information and the rationale behind the study. This is followed by the literature review and information on the current status of small scale RETs in the country. Next it deals with the organizational structure and current subsidy delivery modality of RETs in the country. The evaluation of the effectiveness of the subsidy with the current subsidy delivery modality has been analyzed based on six parameters; Targets and Achievements, Impact of RETs, Subsidy Delivery System Efficiency, Transparency, Sustainability and Effectiveness.
The research shows that the subsidized government program has been successful in achieving its goal to provide basic energy services in rural areas through RETs in terms of its quantitative target. Although the subsidized program is successful in electrifying the rural communities via RETs, the poorest of the poor families are still excluded from the subsidy. The program seems to benefit more the rich and upper middle class families rather than the poor families for which the subsidy was intended. The high capital cost and long subsidy delivery process are the main important reasons for this failure. The author has proposed a new modality which might overcome the time barriers and bureaucratic process in the subsidy delivery mechanism and will decrease the lead time. This will in turn help to reduce the operational cost of the private companies and will encourage more players to enter the market, increase competition and result in lower system costs.
After identifying gaps in the current subsidy delivery modality, the project report ends with the recommendation of a new modality improving the current modality and filling the gaps identified. As this study has some limitations, as described in chapter one, the scope of further works has been listed at the end
Influence of knots and density distribution on compressive strength of wooden foundation piles
No full textThis work investigated the influence of knots on the compression strength of wooden foundation piles. The study involved 110 pile segments sawn from 18 spruce and 9 pine piles with a mean diameter of approximately 200 mm, and moisture contents above fiber saturation. The mechanical properties were determined performing both full-scale compression tests on pile segments, and small-scale experiments on discs sawn from selected segments, considering samples with and without knots. A knot ratio (KR) was defined analysing the knots layout of each wooden pile, and evaluating how the compressive strength was influenced by size, number and layout of knots. As final step, a prediction model was implemented based on the dry density and KR of wooden piles, to estimate the influence of knots on their compressive strength.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Bio-based Structures & Material
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