Internationales Kolloquium über Anwendungen der Informatik und Mathematik in Architektur und Bauwesen : 20. bis 22.7. 2015, Bauhaus-Universität Weimar

The 20th International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering will be held at the Bauhaus University Weimar from 20th till 22nd July 2015. Architects, computer scientists, mathematicians, and engineers from all over the world will meet in Weimar for an interdisciplinary exchange of experiences, to report on their results in research, development and practice and to discuss. The conference covers a broad range of research areas: numerical analysis, function theoretic methods, partial differential equations, continuum mechanics, engineering applications, coupled problems, computer sciences, and related topics. Several plenary lectures in aforementioned areas will take place during the conference. We invite architects, engineers, designers, computer scientists, mathematicians, planners, project managers, and software developers from business, science and research to participate in the conference

Design of autonomous robotic system for removal of porcupine crab spines

Among various types of crabs, the porcupine crab is recognized as a highly potential crab meat resource near the off-shore northwest Atlantic ocean. However, their long, sharp spines make it difficult to be manually handled. Despite the fact that automation technology is widely employed in the commercial seafood processing industry, manual processing methods still dominate in today’s crab processing, which causes low production rates and high manufacturing costs. This thesis proposes a novel robot-based porcupine crab spine removal method. Based on the 2D image and 3D point cloud data captured by the Microsoft Azure Kinect 3D RGB-D camera, the crab’s 3D point cloud model can be reconstructed by using the proposed point cloud processing method. After that, the novel point cloud slicing method and the 2D image and 3D point cloud combination methods are proposed to generate the robot spine removal trajectory. The 3D model of the crab with the actual dimension, robot working cell, and endeffector are well established in Solidworks [1] and imported into the Robot Operating System (ROS) [2] simulation environment for methodology validation and design optimization. The simulation results show that both the point cloud slicing method and the 2D and 3D combination methods can generate a smooth and feasible trajectory. Moreover, compared with the point cloud slicing method, the 2D and 3D combination method is more precise and efficient, which has been validated in the real experiment environment. The automated experiment platform, featuring a 3D-printed end-effector and crab model, has been successfully set up. Results from the experiments indicate that the crab model can be accurately reconstructed, and the central line equations of each spine were calculated to generate a spine removal trajectory. Upon execution with a real robot arm, all spines were removed successfully. This thesis demonstrates the proposed method’s capability to achieve expected results and its potential for application in various manufacturing processes such as painting, polishing, and deburring for parts of different shapes and materials

Industrial Robotics

This book covers a wide range of topics relating to advanced industrial robotics, sensors and automation technologies. Although being highly technical and complex in nature, the papers presented in this book represent some of the latest cutting edge technologies and advancements in industrial robotics technology. This book covers topics such as networking, properties of manipulators, forward and inverse robot arm kinematics, motion path-planning, machine vision and many other practical topics too numerous to list here. The authors and editor of this book wish to inspire people, especially young ones, to get involved with robotic and mechatronic engineering technology and to develop new and exciting practical applications, perhaps using the ideas and concepts presented herein

Semi-nonparametric varying coefficient regression : methodology, theory and application in urban economics

This thesis presents three classes of semi-nonparametric varying coefficient regression for modelling spatial heterogeneity with cross-sectional data, panel data, and functional data, respectively, in the urban context. Chapter 2 presents a selective review of the nonparametric and semi-parametric methodologies. We first examine the estimation of a nonparametric regression using the kernel and the series methods, high lighting the cost of using the nonparametric methods. Next, we review the estimation of a varying coefficient regression and stress its relationship with the popular geographical weighted regression. Finally, we discuss the estimation of a functional linear regression, where the independent variable itself is a function. The functional principal component and Tikhonov regularisation are introduced subsequently to estimate the model. Chapter 3 considers a spatially varying coefficient regression model over irregularly shaped areas. We develop a novel methodology that combines local polynomials and a non-Euclidean metric, called geodesic distance, to achieve both coefficient smoothing and spatial prediction over complex regions. We implement a series of Monte Carlo simulation studies to test the proposed methodology. The results suggest that our method performs better in the estimated coefficients as well as the prediction than alternative methods. Finally, we apply the method to the housing market in Aveiro, Portugal, a coastal area separated by lagoons and rivers. The results highlight the importance of modelling spatial heterogeneity and dependence in a hedonic regression. Chapter 4 presents a spatiotemporally varying coefficient regression model which extends the spatially varying coefficient regression model into the temporal dimension. A three-dimensional local polynomial method is applied to estimate the coefficient. The Monte-Carlo simu lations show that the proposed methodology outperforms the existing geographical and temporal weighted regression. Empirically, we apply the methodology to study the relationship between human activities and consumption amenities in Beijing. To measure the human activi ties and the distribution of the consumption amenities, we collect two unique datasets, a high-resolution mobile phone positioning dataset from Wechat, a mobile social-networking application, and a point-of-interest(POI) dataset from Meituan-Dianping, a crowd-sourcing review website. The results show that the spatial configurations for the consumption amenities play a significant role in attracting human activities, after controlling for a wide range of location-specific characteristics. However, the effects vary substantially over space and a 24-hour time span. The results provide insights into the geographic contextual uncertainties of local amenities in shaping the rise and fall in the city liveliness. Chapter 5 proposes a novel methodology called sieve continuum generalised method of moments to estimate a functional linear regression model. The methodology uses the sieve method to achieve dimension reduction and the continuum generalised method of moments to exploit all the moment conditions. It provides a general framework for estimating a functional linear regression with exogenous regressors as well as a functional instrumental variable regression. The proposed estimator has a closed-form which makes it easy to implement and intuitively appealing. Finally, we derive the optimal rate of convergence for the estimator. Chapter 6 concludes with the summaries, the limitations of the thesis, as well as the directions for future researches

Proceedings of the Twenty-Third Annual Software Engineering Workshop

The Twenty-third Annual Software Engineering Workshop (SEW) provided 20 presentations designed to further the goals of the Software Engineering Laboratory (SEL) of the NASA-GSFC. The presentations were selected on their creativity. The sessions which were held on 2-3 of December 1998, centered on the SEL, Experimentation, Inspections, Fault Prediction, Verification and Validation, and Embedded Systems and Safety-Critical Systems

A New Design Method Framework for Open Origami Design Problems

With the development of computer science and manufacturing techniques, modern origami is no longer just used for making artistic shapes as its traditional counterpart was many centuries ago. Instead, the outstanding lightweight and high flexibility of origami structures has expanded their engineering application in aerospace, medical devices, and architecture. In order to support the automatic design of more complex modern origami structures, several computational origami design methods have been established. However these methods still focus on the problem of determining a crease pattern to fold into an exact pre-determined shape. And these methods apply deductive logic and function for only one type of topological origami structure. In order to drop the topological constraints on the shapes, this dissertation introduces the research on the development and implementation of the abductive evolutionary design methods to open origami design problems, which is asking for their designs to achieve geometric and functional requirements instead of an exact shape. This type of open origami design problem has no formal computational solutions yet. Since the open origami design problem requires searching for solutions among arbitrary candidates without fixing to a certain topological formation, it is NP-complete in computational complexity. Therefore, this research selects the genetic algorithm (GA) and one of its variations – the computational evolutionary embryogeny (CEE) – to solve origami problems. The dissertation made two major contributions. One contribution is on creating the GA-based/abstract design method framework on open origami design problems. The other contribution is on the geometric representation of origami designs that directs the definition and mapping of their genetic representation and physical representation. This research introduced two novel geometric representations, which are the “ice-cracking” and the pixelated multicellular representation (PMR). The proposed design methods and the adapted evolutionary operators have been testified by two open origami design problems of making flat-foldable shapes with desired profile area and rigid-foldable 3D water containers with desired volume. The results have proved the proposed methods widely applicable and highly effective in solving the open origami design problems

Reliable and Safe Motion Control of Unmanned Vehicles

Unmanned vehicles (UVs) are playing an increasingly significant role in modern daily life. In the past decades, numerous commercial, scientific, and military communities across the world are developing fully autonomous UVs for a variety of applications, such as environmental monitoring and surveillance, post-disaster search and rescue, border patrol, natural resources exploration, and experimental platforms for new technologies verification. The excessive opportunities and threats that come along with these diverse applications have created a niche demand for UVs to extend their capabilities to perform more sophisticated and hazardous missions with greater autonomy, lower costs of development and operation, improved personnel safety and security, extended operational range (reliability) and precision, as well as increased flexibility in sophisticated environments including so-called dirty, dull, harsh, and dangerous missions. In order to successfully and effectively execute missions and meet their corresponding performance criteria and overcome these ever-increasing challenges, greater autonomy together with more advanced reliable and safe motion control systems are required to offer the critical technologies for ensuring intelligent, safe, reliable, and efficient control of UVs in the presence of disturbances, actuator saturation, and even actuator faults, especially for practical applications. This thesis concentrates on the development of different reliable and safe motion control algorithms/strategies applicable to UVs, in particular, unmanned aerial vehicles (UAVs) and unmanned surface vehicles (USVs). A number of contributions pertaining to the fault detection and diagnosis (FDD), fault-tolerant control (FTC), disturbance estimation and compensation, and actuator saturation avoidance have been made in this thesis. In addition to the control problems, this thesis also presents several guidance-related contributions, including adaptive observer-based line-of-sight (LOS) guidance law, time-varying lookahead distance scheme, piecewise path switching criterion for guiding a single UV, as well as a proportional-integral (PI) type of leader-follower formation guidance strategy for a group of UVs

Acceleration for the many, not the few

Although specialized hardware promises orders of magnitude performance gains, their uptake has been limited by how challenging it is to program them. Hardware accelerators present challenges programmers are not used to, exposing details of the hardware that are often hidden and requiring new programming styles to use them effectively. Existing programming models often involve learning complex and hardware-specific APIs, using Domain Specific Languages (DSLs), or programming in customized assembly languages. These programming models for hardware accelerators present a significant challenge to uptake: a steep, unforgiving, and untransferable learning curve. However, programming hardware accelerators using traditional programming models presents a challenge: mapping code not written with hardware accelerators in mind to accelerators with restricted behaviour. This thesis presents these challenges in the context of the acceleration equation, and it presents solutions to it in three different contexts: for regular expression accelerators, for API-programmable accelerators (with Fourier Transforms as a key case-study) and for heterogeneous coarse-grained reconfigurable arrays (CGRAs). This thesis shows that automatically morphing software written in traditional manners to fit hardware accelerators is possible with no programmer effort and that huge potential speedups are available

An Experimental and Theoretical Investigation of Novel Aircraft Drag Reduction

Air transportation is an important part of the world’s economic and indispensable transportation system. The major institutions in the world and the aviation authorities are well aware of the demanding expectations of the public for cheaper transportation cost and at the same time the need to reduce the negative impact of aircraft or air-transportation system on the atmosphere which include noise around airports and global warming to attain sustainability, reduction in the emission of green-house gases such Nitrogen oxides (x) and Carbon di-oxide. In order to achieve such a balance in the future, a strategy is required to match competitive excellence dedicated to meeting the demands of society while at the same time being cost effective for the airline companies and operating aviation authorities. Such a vision or concept cannot be realised without making further technological breakthroughs in engineering fields such as Aerodynamics and other discipline including materials and structures. Improving aircraft aerodynamic performance will have a direct impact on helping to implement these goals. Improving aircraft drag capabilities remains one of the big challenges faced by manufacturers of transport aircraft. It is known that for a typical transport aircraft drag, the induced drag amounts to about 40% of the total drag at cruise flight conditions and about 80 –90 percent of the total drag during aircraft take off. The skin friction drag constitute approximately one half of the total Aircraft drag at cruise flight configuration making up most of the remaining percentage of drag at cruise condition. The use of winglets or other wing-tip devices as a drag reduction device play a significant role in improving aircraft performance by acting as passive devices to reduce drag and enhance aircraft performance. In this thesis, four novel spiroid drag reduction devices are presented which were designed and optimised using STAR-CCM+ Optimate + which uses the SHERPA search algorithm as its optimisation tool. The objective of the optimisation process was set to maximise the lift-to-drag ratio. A low fidelity mesh model was used during the optimisation and the results were verified by using high-fidelity physics and mesh model. The developed devices showed an improve CL/CD ratio of up to 11 percent and improved CL by up to 7 percent while reducing CD by up to 4 percent with an 18 - 24 percent reduction in induced drag observed as well. The devices showed consistency in performance at several Mach numbers and angles of attacks. Thus, suggesting that such devices could be used over a wide range of flight regimes on aircraft or UAVs. The study also successfully demonstrated the capability to using this optimisation process in the design and development of such devices. Furthermore, a numerical investigation and wind tunnel verification study was performed on a wing tip turbine to ascertain the aerodynamic performance modification of using such a device at several Mach numbers, angles of attack, propeller rpms and sensitivity of propeller nacelle positions at the wing tip. The obtained results revealed a trend on the nacelle position to achieve the most improved aerodynamic performance. A CL/CD ratio improvement of up to 7 percent, CL modification of approximate 4 percent and CD reduction of up to 4 percent were achieved. In addition to demonstrate an appreciation of some of the wider implication of installing wing tip devices, a flutter analysis on a rectangular clean wing with added variable mass at the wing tip was performed. The result showed that the added masses had no significant implication on the flutter characteristics of the wing