1,002,966 research outputs found
Recommended from our members
Implementation and Evaluation of Novel Buildstyles in Fused Deposition Modeling (FDM)
Previous investigations have shown that the optimization of extrusion dynamics in .conjunction with the buildstyle pattern is of paramount importance to increase part quality in
Fused Deposition Modeling (FDM). Recently domain decomposition and space filling
curves have been introduced for slice generation in FDM [1]. The current work focuses
on the implementations of fractal-like buildstyle .patterns using. Simulated Annealing [2,
3], Lin-Kernighan algorithms [4] and Construction Procedures based on Nearest
Neighbor Heuristics [5]. These computational optimization procedures are able to
generate filling patterns that allow the continuous deposition of a single road to fill arbitrary shaped domains. The necessary software modules to produce arbitrary threedimensional artifacts have been developed and are evaluated with respect to part quality
and build time.Mechanical Engineerin
Development of computer aided design of rectangular reinforced concrete column by using Visual Basic 6.0 / Mohd Akmal Salleh
Column is one of the vital parts in construction. It needs to be design precisely with accurate calculation in order to avoid any failure in construction. There are 2 main types of column that are Braced Column and Unbraced Column. Each of these 2 columns has its own types of classification. In order to design these column its types of classification has to be taken in consideration during calculation. However the most common column used is Braced column because buildings usually have shear walls. As the calculations in designing columns are tedious, developing a simple but yet affective software using Visual Basic is appropriate. The software will save time in designing column hence allow us to recheck our calculation easily. However, aside from calculation process of column design, the detailing and its reinforcement arrangement are also important to be determined. Finally, all the design process still refers to the design techniques of BS 8110 Part 1, BS 8110 Part 2 and BS 8110 Part 3
Cloudbus Toolkit for Market-Oriented Cloud Computing
This keynote paper: (1) presents the 21st century vision of computing and
identifies various IT paradigms promising to deliver computing as a utility;
(2) defines the architecture for creating market-oriented Clouds and computing
atmosphere by leveraging technologies such as virtual machines; (3) provides
thoughts on market-based resource management strategies that encompass both
customer-driven service management and computational risk management to sustain
SLA-oriented resource allocation; (4) presents the work carried out as part of
our new Cloud Computing initiative, called Cloudbus: (i) Aneka, a Platform as a
Service software system containing SDK (Software Development Kit) for
construction of Cloud applications and deployment on private or public Clouds,
in addition to supporting market-oriented resource management; (ii)
internetworking of Clouds for dynamic creation of federated computing
environments for scaling of elastic applications; (iii) creation of 3rd party
Cloud brokering services for building content delivery networks and e-Science
applications and their deployment on capabilities of IaaS providers such as
Amazon along with Grid mashups; (iv) CloudSim supporting modelling and
simulation of Clouds for performance studies; (v) Energy Efficient Resource
Allocation Mechanisms and Techniques for creation and management of Green
Clouds; and (vi) pathways for future research.Comment: 21 pages, 6 figures, 2 tables, Conference pape
Team Relationship and Knowledge Management in Construction Projects in Thailand Part 2: Network Relationship Analysis Using UCINET Software
The study of network relationship using UCINET program in part 1 was inspired by the problematic fragmented structure of a construction project development team. In this paper, the multi-stage project development process as another key factor that underlies the construction industry’s poor performance is addressed. Knowledge management is then proposed as another key solution to achieve the more effective project development in Thailand context. Based on Nonaka and Takeuchi’s 1995 knowledge conversion model, representatives from key project members’ organisations that developed recently complete large commercial residential projects in Bangkok central business area were asked in semi-structured interviews about organisational knowledge management process using a set of standardised questions. The outcomes show the moderate efficiency due to key project members’ unawareness of knowledge potentials. A three-stage framework is also proposed to identify key project members, strengthen network relationship and improve organisational knowledge management capability to achieve the better project development performance
Recommended from our members
Understanding construction delay analysis and the role of pre-construction programming
Copyright © 2013, American Society of Civil Engineers. This is the author's accepted manuscript. The final published article is available from the link below.Modern construction projects commonly suffer from delay in their completions. The resolution of time and cost claims consequently flowing from such delays continues to remain a difficult undertaking for all project parties. A common approach often relied on by contractors and their employers (or their representatives) to resolve this matter involves applying various delay analysis techniques, which are all based on construction programs originally developed for managing the project. However, evidence from literature suggests that the reliability of these techniques in ensuring successful claims resolution are often undermined by the nature and quality of the underlying program used. As part of a wider research carried out on delay and disruption analysis in practice, this paper reports on an aspect of the study aimed at exploring preconstruction stage programming issues that affect delay claims resolutions. This aspect is based on an in-depth interview with experienced construction planning engineers in the United Kingdom, conducted after an initial large-scale survey on delay and disruption techniques usage. Summary of key findings and conclusions include: (1) most contractors prefer to use linked bar chart format for their baseline programs over conventional critical path method (CPM) networks; (2) baseline programs are developed using planning software packages. Some of these pose difficulties when employed for most delay analysis techniques, except for simpler ones; (3) manpower loading graphs are not commonly developed as part of the main deliverables during preconstruction stage planning. As a result, most programs are not subjected to resource loading and leveling for them to accurately reflect planned resource usage on site. This practice has detrimental effects on the reliability of baseline programs in their use for resolving delay claims; and (4) baseline program development involves many different experts within construction organizations as expected, but with very little involvement of the employer or its representative. Active client involvement is however quite important as it would facilitate quick program approval/acceptance before construction, a necessary requirement for early delay claims settlement, which otherwise are often left unresolved long after the delaying events with the potential of generating into expensive disputes. The study results provide a better understanding of the key issues that need attention if improvements are to be made in delay claim resolutions. Additional research focusing on the testing of these results using a much larger sample and rigorous statistical analysis for generalization purposes would be helpful in advancing the limited knowledge of this subject matter
Reproducible geoscientific modelling with hypergraphs
Reproducing the construction of a geoscientific model is a hard task. It requires the availability of all required data and an exact description how the construction was performed. In practice data availability and the exactness of the description is often lacking. As part of this thesis I introduce a conceptual framework how geoscientific model constructions can be described as directed acyclic hypergraphs, how such recorded construction graphs can be used to reconstruct the model, and how repetitive constructions can be used to verify the reproducibility of a geoscientific model construction process. In addition I present a software prototype, implementing these concepts. The prototype is tested with three different case studies, including a geophysical measurement analysis, a subsurface model construction and the calculation of a hydrological balance model.:1. Introduction
1.1. Survey on Reproducibility and Automation for Geoscientific Model Construction
1.2. Motivating Example
1.3. Previous Work
1.4. Problem Description
1.5. Structure of this Thesis
1.6. Results Accomplished by this Thesis
2. Terms, Definitions and Requirements
2.1. Terms and Definitions
2.1.1. Geoscientific model
2.1.2. Reproducibility
2.1.3. Realisation
2.2. Requirements
3. Related Work
3.1. Overview
3.2. Geoscientific Data Storage Systems
3.2.1. PostGIS and Similar Systems
3.2.2. Geoscience in Space and Time (GST)
3.3. Geoscientific Modelling Software
3.3.1. gOcad
3.3.2. GemPy
3.4. Experimentation Management Software
3.4.1. DataLad
3.4.2. Data Version Control (DVC)
3.5. Reproducible Software Builds
3.6. Summarised Releated Work
4. Concept
4.1. Construction Hypergraphs
4.1.1. Reproducibility Based on Construction Hypergraphs
4.1.2. Equality definitions
4.1.3. Design Constraints
4.2. Data Handling
5. Design
5.1. Application Structure
5.1.1. Choice of Application Architecture for GeoHub
5.2. Extension Mechanisms
5.2.1. Overview
5.2.2. A Shared Library Based Extension System
5.2.3. Inter-Process Communication Based Extension System
5.2.4. An Extension System Based on a Scripting Language
5.2.5. An Extension System Based on a WebAssembly Interface
5.2.6. Comparison
5.3. Data Storage
5.3.1. Overview
5.3.2. Stored Data
5.3.3. Potential Solutions
5.3.4. Model Versioning
5.3.5. Transactional security
6. Implementation
6.1. General Application Structure
6.2. Data Storage
6.2.1. Database
6.2.2. User-provided Data-processing Extensions
6.3. Operation Executor
6.3.1. Construction Step Descriptions
6.3.2. Construction Step Scheduling
6.3.3. Construction Step Execution
7. Case Studies
7.1. Overview
7.2. Geophysical Model of the BHMZ block
7.2.1. Provided Data and Initial Situation
7.2.2. Construction Process Description
7.2.3. Reproducibility
7.2.4. Identified Problems and Construction Process Improvements
7.2.5. Recommendations
7.3. Three-Dimensional Subsurface Model of the Kolhberg Region
7.3.1. Provided Data and Initial Situation
7.3.2. Construction Process Description
7.3.3. Reproducibility
7.3.4. Identified Problems and Construction Process Improvements
7.3.5. Recommendations
7.4. Hydrologic Balance Model of a Saxonian Stream
7.4.1. Provided Data and Initial Situation
7.4.2. Construction Process Description
7.4.3. Reproducibility
7.4.4. Identified Problems and Construction Process Improvements
7.4.5. Recommendations
7.5. Lessons Learned
8. Conclusions
8.1. Summary
8.2. Outlook
8.2.1. Parametric Model Construction Process
8.2.2. Pull and Push Nodes
8.2.3. Parallelize Single Construction Steps
8.2.4. Provable Model Construction Process Attestation
References
Appendi
Asymptotic Analysis of Inpainting via Universal Shearlet Systems
Recently introduced inpainting algorithms using a combination of applied
harmonic analysis and compressed sensing have turned out to be very successful.
One key ingredient is a carefully chosen representation system which provides
(optimally) sparse approximations of the original image. Due to the common
assumption that images are typically governed by anisotropic features,
directional representation systems have often been utilized. One prominent
example of this class are shearlets, which have the additional benefitallowing
faithful implementations. Numerical results show that shearlets significantly
outperform wavelets in inpainting tasks. One of those software packages,
www.shearlab.org, even offers the flexibility of usingdifferent parameter for
each scale, which is not yet covered by shearlet theory.
In this paper, we first introduce universal shearlet systems which are
associated with an arbitrary scaling sequence, thereby modeling the previously
mentioned flexibility. In addition, this novel construction allows for a smooth
transition between wavelets and shearlets and therefore enables us to analyze
them in a uniform fashion. For a large class of such scaling sequences, we
first prove that the associated universal shearlet systems form band-limited
Parseval frames for consisting of Schwartz functions.
Secondly, we analyze the performance for inpainting of this class of universal
shearlet systems within a distributional model situation using an
-analysis minimization algorithm for reconstruction. Our main result in
this part states that, provided the scaling sequence is comparable to the size
of the (scale-dependent) gap, nearly-perfect inpainting is achieved at
sufficiently fine scales
Structural design for ponding of rainwater on roof structures
Ponding of rainwater is a special load case that can lead to roof collapse. In Dutch building practice the most frequently occurring damage cases are failures of flat roof structures caused by ponding of rainwater. In the Dutch code for loadings and deformations NEN6702 [1] and the Dutch guidelines for practice regarding ponding NPR 6703 [2], principles and guidelines for the determination of rainwater loads are given. The Dutch code [1] prescribes a complex iterative procedure for ponding of rainwater. Today, there are a number of computer software programs available to support the structural designer in this iteration method. However, to keep insight in the process of rainwater ponding, a simple design method for ponding of slightly sloping flat (steel) roof structures was developed. The method is described in the first part of this article. In the second part a sensitivity analysis for design and construction inaccuracies is presented. It is shown that roofs, that are seemingly stiff enough to withstand ponding, need partial safety factors substantially greater than normally used to account for construction inaccuracies. A proposal for the partial safety factor related to roof stiffness and construction inaccuracies is given
A Visual Approach to Construction Cost Estimating
Construction cost estimating is considered one of the most important and critical phases of a construction project. Preparing reliable and accurate estimates to help decision makers is the most challenging assignment that estimators face. An estimate is not only necessary for proposal preparation but also for several project management functions. Despite the importance of estimating, it has remained a very time consuming process. The most inefficient part of construction cost estimating is determination of the amount of resources needed for the construction of a project. This is also known as quantity takeoff. Quantity takeoff is a very long and error-prone process that is performed manually by estimators. Missing or duplicating work items are among the errors that can occur during the quantity takeoff process.
New Parametric CAD software has recently attained widespread attention in the Architectural, Engineering, and Construction (AEC) industry. It represents the development and use of computer-generated models to simulate the planning, design, construction and operation of a facility. It helps architects, engineers, and contractors visualize what is to be built in a simulated environment and to identify potential design, construction or operational problems. The model created from parametric CAD software will significantly increase construction cost estimator productivity by substantially reducing the manual work necessary for performing quantity takeoffs.
This study presents a methodology that uses parametric CAD software and visualization technologies to streamline the estimating process. Although this methodology won\u27t totally automate the estimating process, it will help in the following areas: (1) providing a navigable 3D model of the project, (2) simplifying the quantity takeoff process, and (3) eliminating manual calculations and search for data. This study uses visualization technologies to navigate through a 3D CAD model. This would provide the estimator with a tool to improve the understanding of the location and relationships between elements in a model. The quantity takeoff process may be simplified by using properties and geometry information extracted from the 3D CAD model. This study also uses a database technology to store labor, equipment, and material cost data. This helps eliminate manual calculations and enables an estimator to search for data stored in the database. A case study is presented to illustrate the process and capabilities of the developed system
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