Cumincad : CUMINCAD Papers : Search Results

CumInCAD is a Cumulative Index about publications in Computer Aided Architectural Design
supported by the sibling associations ACADIA, CAADRIA, eCAADe, SIGraDi, ASCAAD and CAAD futures

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_id	acadia21_328
id	acadia21_328
authors	Akbari, Mostafa; Lu, Yao; Akbarzadeh, Masoud
year	2021
title	From Design to the Fabrication of Shellular Funicular Structures
source	ACADIA 2021: Realignments: Toward Critical Computation [Proceedings of the 41st Annual Conference of the Association of Computer Aided Design in Architecture (ACADIA) ISBN 979-8-986-08056-7]. Online and Global. 3-6 November 2021. edited by B. Bogosian, K. Dörfler, B. Farahi, J. Garcia del Castillo y López, J. Grant, V. Noel, S. Parascho, and J. Scott. 328-339.
doi	https://doi.org/10.52842/conf.acadia.2021.328
summary	Shellular Funicular Structures (SFSs) are single-layer, two-manifold structures with anticlastic curvature, designed in the context of graphic statics. They are considered as efficient structures applicable to many functions on different scales. Due to their complex geometry, design and fabrication of SFSs are quite challenging, limiting their application in large scales. Furthermore, designing these structures for a predefined boundary condition, control, and manipulation of their geometry are not easy tasks. Moreover, fabricating these geometries is mostly possible using additive manufacturing techniques, requiring a lot of supports in the printing process. Cellular funicular structures (CFSs) as strut-based spatial structures can be easily designed and manipulated in the context of graphic statics. This paper introduces a computational algorithm for translating a Cellular Funicular Structure (CFS) to a Shellular Funicular Structure (SFS). Furthermore, it explains a fabrication method to build the structure out of a flat sheet of material using the origami/ kirigami technique as an ideal choice because of its accessibility, processibility, low cost, and applicability to large scales. The paper concludes by displaying a structure that is designed and fabricated using this technique.
series	ACADIA
type	paper
email
last changed	2023/10/22 12:06

_id	ecaade2014_065
id	ecaade2014_065
authors	Daniel Prohasky, Rafael Moya Castro, Simon Watkins, Jane Burry and Mark Burry
year	2014
title	Wind sensing with real-time visualisations for Designers - An approach to understanding wind phenomena for pedestrian comfort using low cost wind sensors
source	Thompson, Emine Mine (ed.), Fusion - Proceedings of the 32nd eCAADe Conference - Volume 1, Department of Architecture and Built Environment, Faculty of Engineering and Environment, Newcastle upon Tyne, England, UK, 10-12 September 2014, pp. 165-171
doi	https://doi.org/10.52842/conf.ecaade.2014.1.165
wos	WOS:000361384700016
summary	The evaluation of a low-tech wind sensing platform for urban aerodynamic simulations relevant to pedestrian comfort. In this paper, the wind canyon effect is simulated with two different building morphologies. The platform provides conceptual knowledge of the dynamics in wind relevant for designers, architectural practitioners and students of design. Low-cost hot wire anemometry is utilised for the design of an Experimental Fluid Dynamic (EFD) wind sensing network interface. This paper explores the validity of the sensing platform for a new approach for non-wind engineers to gain a better understanding of the dynamics of wind. The influence of real-time feedback from quantified wind on the understanding of wind phenomena for non-wind engineers is discussed and compared with post analysis data. It was found that real-time quantified feedback from wind intrigues and stimulates the intuitive notion of wind dynamics through discussion, however post analysis remains critical to evaluate building design performance.
keywords	Wind sensing; real-time feedback; experimental fluid dynamics; hot-wire anemometry; atmospheric boundary layer
series	eCAADe
email
last changed	2022/06/07 07:55

_id	ecaade2018_414
id	ecaade2018_414
authors	Liapi, Katherine and Papantoniou, Andreana
year	2018
title	Square Tessellation Patterns on Double Layer Minimal Surface Structures - Geometric Investigation and Design Algorithms
source	Kepczynska-Walczak, A, Bialkowski, S (eds.), Computing for a better tomorrow - Proceedings of the 36th eCAADe Conference - Volume 2, Lodz University of Technology, Lodz, Poland, 19-21 September 2018, pp. 385-390
doi	https://doi.org/10.52842/conf.ecaade.2018.2.385
summary	Minimal surfaces, defined as surfaces of the smallest area spanned by a given boundary present advantages for architectural applications in terms of their structural and material performance. Therefore, the investigation of their properties including their geometric ones deserve special attention. In this regard, methods for tessellating minimal surfaces need to be studied. In this paper, patterns that consist of four squares with partly overlapping sides have been considered. A constrain in this study was the square tiles maintained their planarity. Three different types of surfaces have been considered, namely the helicoid, catenoid and Enneper's surface. Design algorithms that generate tiling patterns in all three minimal surface types have been developed and are presented in the paper. The geometric investigation of the application of the developed methods to double layer structures has also been examined and discussed in the paper. Finally, the accuracy of the developed algorithms has been tested through the construction of a physical model.
keywords	minimal surfaces; double layer; square tessellation
series	eCAADe
email
last changed	2022/06/07 07:59

_id	acadia12_97
id	acadia12_97
authors	Lilley, Brian ; Hudson, Roland ; Plucknett, Kevin ; Macdonald, Rory ; Cheng, Nancy Yen-Wen ; Nielsen, Stig Anton ; Nouska, Olympia ; Grinbergs, Monika ; Andematten, Stephen ; Baumgardner, Kyle ; Blackman, Clayton ; Kennedy, Matthew ; Chatinthu, Monthira ; Tianchen, Dai ; Sheng-Fu, Chen
year	2012
title	Ceramic Perspiration: Multi-Scalar Development of Ceramic Material
source	ACADIA 12: Synthetic Digital Ecologies [Proceedings of the 32nd Annual Conference of the Association for Computer Aided Design in Architecture (ACADIA) ISBN 978-1-62407-267-3] San Francisco 18-21 October, 2012), pp. 97-108
doi	https://doi.org/10.52842/conf.acadia.2012.097
summary	Ceramic building material is a useful passive modulator of the environment. The subject area is based on traditional cultural and material knowledge of clay properties: from amphora to rammed earth building; and ranges to present uses: from desiccants and space shuttle tile patterns to bio-ceramics. The primary consideration is to control material density and porosity in a tile component, in response to specific environmental conditions. This depends on a number of key physical principles: the ability of the material to absorb thermal energy, the ability to absorb and then ‘wick’ moisture within the pore structure, and the decrement factor or ‘time lag’ of the effect. The interplay between these properties point to the importance of directionality in the porous microstructure, at the boundary layer. Material characteristics have been investigated in the laboratory at a micron scale and in the ceramics workshop at full scale, with some interplay between the two. Recent work done on monitoring has led to the development of software tools that allow feedback (approaching real time)- a visual representation of the dynamic thermal and hygrometric properties involved.
keywords	Synthetic tectonics , composite materials , smart assemblies , emerging material processes , Responsive environments , sensing , real-time computation , feedback loops , Information Visualization
series	ACADIA
type	normal paper
email
last changed	2022/06/07 07:59

_id	ecaade2022_238
id	ecaade2022_238
authors	Tommasi, Ilaria and Erioli, Alessio
year	2022
title	Branch Making Shells - A multi-agent systems application for the formation of shell branched structures
source	Pak, B, Wurzer, G and Stouffs, R (eds.), Co-creating the Future: Inclusion in and through Design - Proceedings of the 40th Conference on Education and Research in Computer Aided Architectural Design in Europe (eCAADe 2022) - Volume 2, Ghent, 13-16 September 2022, pp. 123–132
doi	https://doi.org/10.52842/conf.ecaade.2022.2.123
summary	This research explores an application of multi-agent systems to the generation of single- layer branched shell structures for architectural application. The study is prompted by the structure and pattern-making capacity of climbing plants’ growth behaviours, in which growth history (affected by internal local processes and environmental conditions), generates a multi-performant outcome. The digital system merges parts of the Space Colonization Algorithm (SCA) with agent-based logic, leveraging iterative local interactions to coherently embed environmental conditions and static requirements in the production of a coherent structural network on a boundary surface, which is translated in a beams-and-nodes glued laminated timber structure. The paper exposes the method and its applications to the case study of a pavilion, discussing geometric constructability’s challenges and limits.
keywords	Multi-Agent System, Space Colonization Algorithm, Branching Structures, Structural Shells, Glued Laminated Timber
series	eCAADe
email
last changed	2024/04/22 07:10

_id	ascaad2022_032
id	ascaad2022_032
authors	Ibrahim, Aly; Omar, Walid; Ebrahim, Sherif; Abdelmohsen, Sherif
year	2022
title	Moisture-Harvesting Lizard Skins as an Inspiration for Performative Building Envelopes in Arid Climates
source	Hybrid Spaces of the Metaverse - Architecture in the Age of the Metaverse: Opportunities and Potentials [10th ASCAAD Conference Proceedings] Debbieh (Lebanon) [Virtual Conference] 12-13 October 2022, pp. 515-528
summary	Research on shape-shifting adaptive architectural skins has recently focused on bio-inspired programmable materials. Only a few studies however examine the microstructure of living organisms, especially in terms of morphological adaptation in harsh climatic conditions. This paper explores the microstructure of moisture-harvesting lizard skins, specifically the Trapelus species of the Agamidae family in North-East Africa, as an inspiration for programmable materials in adaptive building skins in the arid climate of Egypt. The paper investigates the ability to improve the durability and morphological capabilities of programmable materials based on surface formation, utilizing digital fabrication techniques. A series of physical experiments were conducted on different samples of 3D printed wood filament under several humidity conditions, as a single layer, with textured patterns, and with the addition of potassium chloride as a moisture-harvesting chemical composite. The paper concluded that materials composed of textured patterns and moisture-harvesting chemical composites exhibited the highest moisture retention, therefore leading to advantages in its use in adaptive building skins in arid climates, through a wide variety of design possibilities for performative building envelopes.
series	ASCAAD
email
last changed	2024/02/16 13:24

_id	ecaade2023_130
id	ecaade2023_130
authors	Nas, Mehmet Oguz and Gönenç Sorguç, Arzu
year	2023
title	4D Printing of Hygroscopic Wood Based Actuators for Climate Responsive Skin
source	Dokonal, W, Hirschberg, U and Wurzer, G (eds.), Digital Design Reconsidered - Proceedings of the 41st Conference on Education and Research in Computer Aided Architectural Design in Europe (eCAADe 2023) - Volume 1, Graz, 20-22 September 2023, pp. 439–448
doi	https://doi.org/10.52842/conf.ecaade.2023.1.439
summary	Adaptive building systems aim to enhance user comfort and reduce energy consumption in buildings. However, sensing the environment and generating relevant motion requires complex systems. The high costs associated with the installation, maintenance, and energy consumption of traditional systems hinder their widespread adoption. A more efficient alternative can be found in nature by harnessing the intrinsic properties of materials. Recent studies inspired by pinecones showed that wood bilayers with different swelling and shrinking ratios can passively shape change in response to environmental humidity. The morphing direction is determined by fiber orientation, which can be controlled by extrusion-based 3D printers. The existing literature highlights several challenges in utilizing hygroscopic wood actuators for climate-responsive building skins, including the predictability of motion, response speed, and scalability. Hence, this research investigates the design space at both mesostructural and macrostructural levels for controlled, scaleable motion. To this end, a series of experiments were conducted in a controlled environment to observe the actuation dynamics. The experiments explored design parameters including thickness, porosity, bilayer ratio, layer orientation, and 3D printing parameters such as layer thickness and printing order. Collected data were utilized to construct a model that can predict the actuation and find the configuration for the required motion. Two implementations of this model are proposed. While the first design makes use of combined actuators for motion amplification, the latter employs pre-stressed bistability to control the timing of motion. Both designs were tested at scales of 1/2 and 1 to 1, using a wood-based filament and wood veneer as actuators, respectively. The results demonstrate that the use of multiple joined actuators significantly increases the actuation speed. Moreover, it is shown that the humidity level required to trigger the shape-shifts can be tuned thanks to the pre-stressed bistable structures. This is promising in terms of adaptability to diverse climates and enhancement of energy efficiency in buildings.
keywords	4D Printing Wood, Biomimicry, Hygroscopic Actuators, Pre-stressed Bistability, Climate-Responsive, Responsive Architecture
series	eCAADe
email
last changed	2023/12/10 10:49

_id	0a09
authors	Akin, O., Dave, B. and Pithavadian, S.
year	1987
title	Problem Structuring in Architectural Design
source	February, 1987. [4], 15 p. : ill. includes bibliography
summary	The purpose of this research is to describe in operational terms the process of problem structuring while solving spatial problems in architectural design. The designer's behavior is described in terms of problem structuring, when problem parameters are established or transformed, and in terms of problem solving when these parameters are satisfied in a design solution. As opposed to problem solving, the structuring of problems is an under-studied but crucial aspect of complex tasks such as design. This work is based on observations derived from verbal protocol studies. To consider various levels of skill, the research subjects range from professional architects to novice designers. Subjects are given space planning problems which require them to develop solutions in accordance with individually established constraints and criteria, the majority of which are not explicit stated in the problem description. Based on the results of the protocol analysis, a framework is developed which explains how information processing characteristics, problem structure and different levels of expertise interact to influence the designer behavior
keywords	architecture, design process, problem solving, protocol analysis, problem definition
series	CADline
email
last changed	2003/05/17 10:09

_id	ae05
authors	Akin, Omer
year	1987
title	Expertise of the Architect
source	November, 1987. [13] p. unevenly numbered : ill. includes bibliography
summary	One of the areas where the expertise of the seasoned architect comes out is in the initial structuring of design problems. During problem structuring the parameters and processes used in design are defined. Experienced architects modify these parameters both in global and local levels as a function of the success of their research process. Experienced architects also rely on 'scenarios' acquired through pervious experiences with similar problems to initialize their problem structures or to redefined them
keywords	design, architecture, methods
series	CADline
email
last changed	2003/05/17 10:09

_id	eb5f
authors	Al-Sallal, Khaled A. and Degelman, Larry 0.
year	1994
title	A Hypermedia Model for Supporting Energy Design in Buildings
source	Reconnecting [ACADIA Conference Proceedings / ISBN 1-880250-03-9] Washington University (Saint Louis / USA) 1994, pp. 39-49
doi	https://doi.org/10.52842/conf.acadia.1994.039
summary	Several studies have discussed the limitations of the available CAAD tools and have proposed solutions [Brown and Novitski 1987, Brown 1990, Degelman and Kim 1988, Schuman et al 1988]. The lack of integration between the different tasks that these programs address and the design process is a major problem. Schuman et al [1988] argued that in architectural design many issues must be considered simultaneously before the synthesis of a final product can take place. Studies by Brown and Novitski [1987] and Brown [1990] discussed the difficulties involved with integrating technical considerations in the creative architectural process. One aspect of the problem is the neglect of technical factors during the initial phase of the design that, as the authors argued, results from changing the work environment and the laborious nature of the design process. Many of the current programs require the user to input a great deal of numerical values that are needed for the energy analysis. Although there are some programs that attempt to assist the user by setting default values, these programs distract the user with their extensive arrays of data. The appropriate design tool is the one that helps the user to easily view the principal components of the building design and specify their behaviors and interactions. Data abstraction and information parsimony are the key concepts in developing a successful design tool. Three different approaches for developing an appropriate CAAD tool were found in the literature. Although there are several similarities among them, each is unique in solving certain aspects of the problem. Brown and Novitski [1987] emphasize the learning factor of the tool as well as its highly graphical user interface. Degelman and Kim [1988] emphasize knowledge acquisition and the provision of simulation modules. The Windows and Daylighting Group of Lawrence Berkeley Laboratory (LBL) emphasizes the dynamic structuring of information, the intelligent linking of data, the integrity of the different issues of design and the design process, and the extensive use of images [Schuman et al 19881, these attributes incidentally define the word hypermedia. The LBL model, which uses hypermedia, seems to be the more promising direction for this type of research. However, there is still a need to establish a new model that integrates all aspects of the problem. The areas in which the present research departs from the LBL model can be listed as follows: it acknowledges the necessity of regarding the user as the center of the CAAD tool design, it develops a model that is based on one of the high level theories of human-computer interaction, and it develops a prototype tool that conforms to the model.
series	ACADIA
email
last changed	2022/06/07 07:54

_id	sigradi2013_234
id	sigradi2013_234
authors	Alencar, Viviane; Gabriela Celani
year	2013
title	The Art of Computer Graphics Programming: Translating Pioneer Programs
source	SIGraDi 2013 [Proceedings of the 17th Conference of the Iberoamerican Society of Digital Graphics - ISBN: 978-956-7051-86-1] Chile - Valparaíso 20 - 22 November 2013, pp. 500 - 504
summary	Considering the importance of the use of programming languages for teaching computational design to architects, this paper proposes the translation of computer programs from a pioneer work in this field into a more contemporary programming language. The book The Art of Computer Graphics Programming: A Structured Introduction for Architects and Designers was published in 1987 by William J. Mitchell, Robin Ligget and Thomas Kvan, and remains an important reference for architects. The original Pascal codes in the book were translated into Processing, and made available through an Internet website, along with images and comments, in order to give late Prof. Mitchell’s work the consideration it deserves.
keywords	Processing; Pascal; Computer graphics
series	SIGRADI
email
last changed	2016/03/10 09:47

_id	4d3b
authors	Archea, John
year	1987
title	Puzzle-Making : What Architects Do When No One is Looking
source	New York: Wiley-Interscience, 1987. pp. 37-52. includes bibliography
summary	The thesis of this paper is that architects work in a manner that is antithetical to problem-solving because they cannot explicate desired effects prior to their realization through the design process. In an attempt to clarify architecture's uncommon mode of action the author suggests that instead of specifying what they are trying to accomplish prior to their attempts to accomplish it as problem-solver do, architects treat design as a search for the most appropriate effects that can be attained in a unique context. They seek sets of combinatorial rules that will result in an internally consistent fit between a kit of parts and the effects that are achieved when those parts are assembled in a certain way
keywords	puzzle making, problem solving, architecture, design process
series	CADline
last changed	1999/02/12 15:07

_id	e820
authors	Armstrong, W.W., Green, M. and Lake, R.
year	1987
title	Near- Real-Time Control of Human Figure Models
source	IEEE Computer Graphics and Applications. June, 1987. vol. 7: pp. 52-60 : ill
summary	Includes bibliography. Animating human figures is one of the major problems in computer animation. A recent approach is the use of dynamic analysis to compute the movement of a human figure, given the forces and torques operating within and upon the body. One of the problems with this technique is computing the forces and torques required for particular motions: this has been called the control problem of dynamic analysis. To develop a better understanding of this problem, an interactive interface to a dynamics package has been produced. This interface, along with a collection of low-level motion processes, can be used to control the motion of a human figure model. This article describes both the user interface and the motion processes, along with experiences with this approach
keywords	computer graphics, animation, user interface
series	CADline
last changed	2003/06/02 14:41

_id	8eb4
authors	Athithan, G. and Patnaik, L.M.
year	1987
title	Geometric Searching In Extended CSG Models : Application to Solid Modeling and Viewing
source	February, 1987. 30 p. : ill
summary	In this paper, the CSG representation scheme is augmented with the 'cartesian product.' The sweep method of generating solids is encompassed by this 'Extended CSG' formalism. The point inclusion problem encountered in the area of geometric searching in computational geometry is discussed in the context to solid models represented by 'extended CSG.' A simple algorithm to solve it that has a time complexity O(n), where n is the number of primitives, is presented. Allowing for preprocessing and extra storage, a second efficient algorithm, having a time complexity O(log n), is developed. The relevance of point inclusion problem in solid modelling techniques is indicated. An extended CSG based solid modeling method is proposed. A solution to the problem of hidden line removal, that uses the faster algorithm for the point inclusion problem, is also presented in the paper
keywords	point inclusion, computational geometry, data structures, solid modeling, CSG, computer graphics, hidden lines
series	CADline
last changed	2003/06/02 14:41

_id	266d
authors	Badler, Norman I., Manoochehri, Kamran H. and Walters, Graham
year	1987
title	Articulated Figure Positioning by Multiple Constraints
source	IEEE Computer Graphics and Applications. June, 1987. vol. 7: pp. 28-38 : ill. Includes bibliography
summary	A problem that arises in positioning an articulated figures is the solution of 3D joint positions (kinematics), when joint angles are given. If more than one such goal is to be achieved, the problem is often solved interactively by positioning or solving one component of the linkage, then adjusting another, then redoing the first, and so on. This iterative process is slow and tedious. The authors present a method that automatically solves multiple simultaneous joint position goals. The user interface offers a six-degree-of freedom input device to specify joint angles and goal positions interactively. Examples are used to demonstrate the power and efficiency of this method for key-position animation
keywords	animation, constraints, computer graphics
series	CADline
last changed	2003/06/02 13:58

_id	a60d
authors	Bairstow, Jeffrey N.
year	1987
title	Personal Workstations Redefine Desktop Computing
source	high Technology. March, 1987. pp. 18-23 : ill. includes bibliography: p. 64
summary	Becoming an essential tool in any creative activity, the personal workstations were successfully adopted by software developers for designing both system and application software, by electronics engineers for computer-aided design, and by a wide range of businesses for technical publishing. The rapid adoption of networking and file standards by the workstation manufacturers will undoubtedly put them in a good position to install large networks of both PCs and workstations linked to existing corporate mainframe computers
keywords	hardware, technology, business
series	CADline
last changed	2003/06/02 13:58

_id	0cd8
authors	Baker, Nelson C. and Fenves, Stephen J.
year	1987
title	A Knowledge Acquisition Study of Structural Engineers Performing Preliminary Design
source	92 p. : ill. Pittsburgh, PA: Engineering Design Research Center, CMU, December, 1987. EDRC-12-19-87
summary	This paper describes interviews with experts in structural engineering. Video recordings of the experts performing preliminary structural design for three buildings were obtained. The knowledge acquisition process is described and the conclusions reached are presented. The conclusions are discussed in terms of level of design detail, solution time, distribution of process and domain activities, the use of previous information in the design process, and the use of sketches
keywords	knowledge acquisition, civil engineering, design process, design methods, drafting, systems, protocol analysis
series	CADline
last changed	2003/06/02 10:24

_id	05c2
authors	Balachandran, M. B. and Gero, John S.
year	1987
title	Use of Knowledge in Selection and Control of Optimization Algorithms
source	engineering Optimization. 1987. vol. 12: pp. 163-173
summary	Computers have been widely used in optimization based problem solving processes to assist with the numerical computations. The widespread availability of symbolic computational tools and recent developments in artificial intelligence now make it feasible to expand the role of computers in this area. Various classes of knowledge used to improve the efficiency of the optimization processes are presented in this paper. A prototype system developed in the domain of multicriteria decision making is demonstrated. The system contains knowledge needed to select appropriate optimization algorithms, to control the solution process, and to select alternate algorithms if needed
keywords	multicriteria, algorithms, knowledge base, systems, problem solving, optimization
series	CADline
email
last changed	2003/06/02 13:58

_id	016a
authors	Balachandran, M. B. and Gero, John S.
year	1987
title	A Knowledge-based Approach to Mathematical Design Modeling and Optimization
source	engineering Optimization. 1987. vol. 12: pp. 91-115
summary	Optimization is a well understood process in design domains. Designers formulate their design problems as single criterion or multicriteria optimization problems and then select an appropriate optimization algorithm to search for the optimal values for the design variables. The formulation and algorithm selection procedures have been considered to be activities which relied on substantive human knowledge. This paper describes a computer system, OPTIMA, which formulates design optimization problems from a pseudo-English description into canonical algebraic expressions. It then recognizes the formulation and selects appropriate algorithm(s) for its solution. Finally, it runs the selected algorithm(s) and sends the results back to the original descriptions. Areas of expert knowledge involved in carrying out the above tasks are identified. Such knowledge is explicitly encoded in the system. The basic philosophy and key features of the system are described and are illustrated with examples
keywords	structures, algorithms, knowledge base, systems, optimization, engineering
series	CADline
email
last changed	2003/06/02 13:58

_id	08a1
authors	Balachandran, M.B. and Gero, John S.
year	1987
title	A Knowledge-based Graphical Interface for Structural Design
source	Southampton: CM Publications, 1987. pp. 335-346
summary	This paper describes a knowledge-based graphical interface for the domain of structural engineering. The key aspects of the system include graphics interpretation, feature extraction of graphic objects and the identification of the entity itself. Details of the implementation of a prototype system using Prolog and C are provided. The domain knowledge is represented as frames. Examples are given to illustrate the performance of the system
keywords	structures, user interface, knowledge base, systems, design, engineering, computer graphics, frames
series	CADline
email
last changed	2003/06/02 13:58

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