Search results for: housing defects
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 389

Search results for: housing defects

119 Shape Memory alloy Actuator System Optimization for New Hand Prostheses

Authors: Mogeeb A. Ahmed, Mona F. Taher, Sayed M. Metwalli

Abstract:

Shape memory alloy (SMA) actuators have found a wide range of applications due to their unique properties such as high force, small size, lightweight and silent operation. This paper presents the development of compact (SMA) actuator and cooling system in one unit. This actuator is developed for multi-fingered hand. It consists of nickel-titanium (Nitinol) SMA wires in compact forming. The new arrangement insulates SMA wires from the human body by housing it in a heat sink and uses a thermoelectric device for rejecting heat to improve the actuator performance. The study uses optimization methods for selecting the SMA wires geometrical parameters and the material of a heat sink. The experimental work implements the actuator prototype and measures its response.

Keywords: Optimization, Prosthetic hand, Shape memory alloy, Thermoelectric device, Actuator system

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118 Finite Element Study of a DfD Beam-Column Connection

Authors: Zhi Sheng Lin, K. C. G. Ong, Lado Riannevo Chandra, Bee Hong Angeline Tan, Chat Tim Tam, Sze Dai Pang

Abstract:

Design for Disassembly (DfD) aims to reuse the structural components instead of demolition followed by recycling of the demolition debris. This concept preserves the invested embodied energy of materials, thus reducing inputs of new embodied energy during materials reprocessing or remanufacturing. Both analytical and experimental research on a proposed DfD beam-column connection for use in residential apartments is currently investigated at the National University of Singapore in collaboration with the Housing and Development Board of Singapore. The present study reports on the results of a numerical analysis of the proposed connection utilizing finite element analysis. The numerical model was calibrated and validated by comparison against experimental results. Results of a parametric study will also be presented and discussed.

Keywords: Design for Disassembly (DfD), finite element analysis, parametric study.

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117 Analysis of Behaviour of Real Estate Rates in India- A Case Study of Pune City

Authors: Sayali Sandbhor, Ravindra Bapat, N. B. Chaphalkar

Abstract:

Decisions for investment, buying and selling of properties depend upon the market value of that property. Issues arise in arriving at the actual value of the property as well as computing the rate of returns from the estate. Addressing valuation related issues through an understanding of behavior of real property rates provide the means to explore the quality of past decisions and to make valid future decisions. Pune, an important city in India, has witnessed a high rate of growth in past few years. Increased demand for housing and investment in properties has led to increase in the rates of real estate. An attempt has been made to study the change and behavior of rates of real estate and factors influencing the same in Pune city.

Keywords: Real estate, valuation, property rates, trend analysis

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116 Monitoring of Belt-Drive Defects Using the Vibration Signals and Simulation Models

Authors: A. Nabhan, Mohamed R. El-Sharkawy, A. Rashed

Abstract:

The main aim of this paper is to dedicate the belt drive system faults like cogs missing, misalignment and belt worm using vibration analysis technique. Experimentally, the belt drive test-rig is equipped to measure vibrations signals under different operating conditions. Finite element 3D model of belt drive system is created and vibration response analyzed using commercial finite element software ABAQUS/CAE.  Root mean square (RMS) and Crest Factor will serve as indicators of average amplitude of envelope analysis signals. The vibration signals pattern obtained from the simulation model and experimental data have the same characteristics. It can be concluded that each case of the RMS is more effective in detecting the defect for acceleration response. While Crest Factor parameter has a response with the displacement and velocity of vibration signals. Also it can be noticed that the model has difficulty in completing the solution when the misalignment angle is higher than 1 degree.

Keywords: Simulation model, misalignment, cogs missing and vibration analysis.

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115 Functionalization of Carbon Nanotubes Using Nitric Acid Oxidation and DBD Plasma

Authors: M. Vesali Naseh, A. A. Khodadadi, Y. Mortazavi, O. Alizadeh Sahraei, F. Pourfayaz, S. Mosadegh Sedghi

Abstract:

In this study, multiwall carbon nanotubes (MWNTs) were modified with nitric acid chemically and by dielectric barrier discharge (DBD) plasma in an oxygen-based atmosphere. Used carbon nanotubes (CNTs) were prepared by chemical vapour deposition (CVD) floating catalyst method. For removing amorphous carbon and metal catalyst, MWNTs were exposed to dry air and washed with hydrochloric acid. Heating purified CNTs under helium atmosphere caused elimination of acidic functional groups. Fourier transformed infrared spectroscopy (FTIR) shows formation of oxygen containing groups such as C=O and COOH. Brunauer, Emmett, Teller (BET) analysis revealed that functionalization causes generation of defects on the sidewalls and opening of the ends of CNTs. Results of temperature-programmed desorption (TPD) and gas chromatography(GC) indicate that nitric acid treatment create more acidic groups than plasma treatment.

Keywords: Carbon nanotubes (CNTs), chemical treatment, functionalization, plasma.

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114 Investigation of Stoneley Waves in Multilayered Plates

Authors: Bing Li, Tong Lu, Lei Qiang

Abstract:

Stoneley waves are interface waves that propagate at the interface between two solid media. In this study, the dispersion characteristics and wave structures of Stoneley waves in elastic multilayered plates are displayed and investigated. With a perspective of bulk wave, a reasonable assumption of the potential function forms of the expansion wave and shear wave in nth layer medium is adopted, and the characteristic equation of Stoneley waves in a three-layered plate is given in a determinant form. The dispersion curves and wave structures are solved and presented in both numerical and simulation results. It is observed that two Stoneley wave modes exist in a three-layered plate, that conspicuous dispersion occurs on low frequency band, that the velocity of each Stoneley wave mode approaches the corresponding Stoneley wave velocity at interface between two half infinite spaces. The wave structures reveal that the in-plane displacement of Stoneley waves are relatively high at interfaces, which shows great potential for interface defects detection.

Keywords: Characteristic equation, interface waves, dispersion curves, potential function, Stoneley waves, wave structures.

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113 Pig Husbandry and Solid Manures in a Commercial Pig Farm in Beijing, China

Authors: Roxana Mendoza Huaitalla, Eva Gallmann, Kun Zheng, Xuejun Liu, Eberhard Hartung

Abstract:

Porcine production in China represents approximately the 50% of the worldwide pig production. Information about pig husbandry characteristics in China and manure properties from sows to fatteners in intensive pig farms are not broadly available for scientific studies as it is a time consuming, expensive task and highly inaccessible. This study provides a report about solid pig manures (28% dry matter) in a commercial pig farm located in the peri-urban area of Beijing as well as a general overview of the current pig husbandry techniques including pig breeds, feeds, diseases, housing as well as pig manure and wastewater disposal. The main results are intended to serve as a literature source for young scientists in order to understand the main composition of pig manures as well as to identify the husbandry techniques applied in an intensive pig farm in Beijing.

Keywords: China, heavy metals, intensive pig farming, manure, nutrients, pig growing stages.

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112 Analysis of Different Resins in Web-to-Flange Joints

Authors: W. F. Ribeiro, J. L. N. Góes

Abstract:

The industrial process adds to engineering wood products features absent in solid wood, with homogeneous structure and reduced defects, improved physical and mechanical properties, bio-deterioration, resistance and better dimensional stability, improving quality and increasing the reliability of structures wood. These features combined with using fast-growing trees, make them environmentally ecological products, ensuring a strong consumer market. The wood I-joists are manufactured by the industrial profiles bonding flange and web, an important aspect of the production of wooden I-beams is the adhesive joint that bonds the web to the flange. Adhesives can effectively transfer and distribute stresses, thereby increasing the strength and stiffness of the composite. The objective of this study is to evaluate different resins in a shear strain specimens with the aim of analyzing the most efficient resin and possibility of using national products, reducing the manufacturing cost. First was conducted a literature review, where established the geometry and materials generally used, then established and analyzed 8 national resins and produced six specimens for each.

Keywords: Engineered wood products, structural resin, wood i-joist.

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111 The Prospective Assessment of Zero-Energy Dwellings

Authors: Jovana Dj. Jovanovic, Svetlana M. Stevovic

Abstract:

The highest priority of so called, projected passive houses is to meet the appropriate energy demand. Every single material and layer which is injected into a dwelling has a certain energy quantity stored. The passive houses include optimized insulation levels with minimal thermal bridges, minimum of air leakage through the building, utilization of passive solar and internal gains, and good circulation of air which leans on mechanical ventilation system. The focus of this paper is on passive house features, benefits and targets, their feasibility and energy demands which are set up during each project. Numerous passive house-standards outline the very significant role of zero-energy dwellings towards the modern label of sustainable development. It is clear that the performance of both built and existing housing stock must be addressed if the population across the world sets out the energy objectives. This scientific article examines passive house features since the many passive house cases are launched.

Keywords: Benefits, energy demands, passive houses, sustainable development.

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110 A Study on the Impacts of Computer Aided Design on the Architectural Design Process

Authors: Halleh Nejadriahi, Kamyar Arab

Abstract:

Computer-aided design (CAD) tools have been extensively used by the architects for the several decades. It has evolved from being a simple drafting tool to being an intelligent architectural software and a powerful means of communication for architects. CAD plays an essential role in the profession of architecture and is a basic tool for any architectural firm. It is not possible for an architectural firm to compete without taking the advantage of computer software, due to the high demand and competition in the architectural industry. The aim of this study is to evaluate the impacts of CAD on the architectural design process from conceptual level to final product, particularly in architectural practice. It examines the range of benefits of integrating CAD into the industry and discusses the possible defects limiting the architects. Method of this study is qualitatively based on data collected from the professionals’ perspective. The identified benefits and limitations of CAD on the architectural design process will raise the awareness of professionals on the potentials of CAD and proper utilization of that in the industry, which would result in a higher productivity along with a better quality in the architectural offices.

Keywords: Architecture, architectural practice, computer aided design, CAD, design process.

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109 Comparison of Seismic Retrofitting Methods for Existing Foundations in Seismological Active Regions

Authors: Peyman Amini Motlagh, Ali Pak

Abstract:

Seismic retrofitting of important structures is essential in seismological active zones. The importance is doubled when it comes to some buildings like schools, hospitals, bridges etc. because they are required to continue their serviceability even after a major earthquake. Generally, seismic retrofitting codes have paid little attention to retrofitting of foundations due to its construction complexity. In this paper different methods for seismic retrofitting of tall buildings’ foundations will be discussed and evaluated. Foundations are considered in three different categories. First, foundations those are in danger of liquefaction of their underlying soil. Second, foundations located on slopes in seismological active regions. Third, foundations designed according to former design codes and may show structural defects under earthquake loads. After describing different methods used in different countries for retrofitting of the existing foundations in seismological active regions, comprehensive comparison between these methods with regard to the above mentioned categories is carried out. This paper gives some guidelines to choose the best method for seismic retrofitting of tall buildings’ foundations in retrofitting projects.

Keywords: Existing foundation, landslide, liquefaction, seismic retrofitting.

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108 The Application of an Experimental Design for the Defect Reduction of Electrodeposition Painting on Stainless Steel Washers

Authors: Chansiri Singhtaun, Nattaporn Prasartthong

Abstract:

The purpose of this research is to reduce the amount of incomplete coating of stainless steel washers in the electrodeposition painting process by using an experimental design technique. The surface preparation was found to be a major cause of painted surface quality. The influence of pretreating and painting process parameters, which are cleaning time, chemical concentration and shape of hanger were studied. A 23 factorial design with two replications was performed. The analysis of variance for the designed experiment showed the great influence of cleaning time and shape of hanger. From this study, optimized cleaning time was determined and a newly designed electrical conductive hanger was proved to be superior to the original one. The experimental verification results showed that the amount of incomplete coating defects decreased from 4% to 1.02% and operation cost decreased by 10.5%.

Keywords: Defect reduction, design of experiments, electrodeposition painting, stainless steel.

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107 Numerical Simulation of Investment Casting of Gold Jewelry: Experiments and Validations

Authors: Marco Actis Grande, Somlak Wannarumon

Abstract:

This paper proposes the numerical simulation of the investment casting of gold jewelry. It aims to study the behavior of fluid flow during mould filling and solidification and to optimize the process parameters, which lead to predict and control casting defects such as gas porosity and shrinkage porosity. A finite difference method, computer simulation software FLOW-3D was used to simulate the jewelry casting process. The simplified model was designed for both numerical simulation and real casting production. A set of sensor acquisitions were allocated on the different positions of the wax tree of the model to detect filling times, while a set of thermocouples were allocated to detect the temperature during casting and cooling. Those detected data were applied to validate the results of the numerical simulation to the results of the real casting. The resulting comparisons signify that the numerical simulation can be used as an effective tool in investment-casting-process optimization and casting-defect prediction.

Keywords: Computer fluid dynamic, Investment casting, Jewelry, Mould filling, Simulation.

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106 Investigation of Failures in Wadi-Crossing Pipe Culverts, Sennar State, Sudan

Authors: Magdi M. E. Zumrawi

Abstract:

Crossing culverts are essential element of rural roads. The paper aims to investigate failures of recently constructed wadi-crossing pipe culverts in Sennar state and provide necessary remedial measures. The investigation is conducted to provide an extensive diagnosis study in order to find out the main structural and hydrological weaknesses of the culverts. Literature of steel pipe culverts related to construction practices and common types of culvert failures and their appropriate mitigation measures were reviewed. A detailed field survey was conducted to detect failures and defects appeared on the existing culverts. The results revealed that seepage of water through the embankment and foundation of the culverts leads to excessive erosion and scouring causing sever failures and damages. The design mistakes and poor construction were detected as the main causes of culverts failures. For sustainability of the culverts, various remedial measures are recommended to be considered in urgent rehabilitation of the existing crossings.

Keywords: Culvert, erosion, failure, sustainability.

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105 Real-time Laser Monitoring based on Pipe Detective Operation

Authors: Mongkorn Klingajay, Tawatchai Jitson

Abstract:

The pipe inspection operation is the difficult detective performance. Almost applications are mainly relies on a manual recognition of defective areas that have carried out detection by an engineer. Therefore, an automation process task becomes a necessary in order to avoid the cost incurred in such a manual process. An automated monitoring method to obtain a complete picture of the sewer condition is proposed in this work. The focus of the research is the automated identification and classification of discontinuities in the internal surface of the pipe. The methodology consists of several processing stages including image segmentation into the potential defect regions and geometrical characteristic features. Automatic recognition and classification of pipe defects are carried out by means of using an artificial neural network technique (ANN) based on Radial Basic Function (RBF). Experiments in a realistic environment have been conducted and results are presented.

Keywords: Artificial neural network, Radial basic function, Curve fitting, CCTV, Image segmentation, Data acquisition.

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104 A Detection Method of Faults in Railway Pantographs Based on Dynamic Phase Plots

Authors: G. Santamato, M. Solazzi, A. Frisoli

Abstract:

Systems for detection of damages in railway pantographs effectively reduce the cost of maintenance and improve time scheduling. In this paper, we present an approach to design a monitoring tool fitting strong customer requirements such as portability and ease of use. Pantograph has been modeled to estimate its dynamical properties, since no data are available. With the aim to focus on suspensions health, a two Degrees of Freedom (DOF) scheme has been adopted. Parameters have been calculated by means of analytical dynamics. A Finite Element Method (FEM) modal analysis verified the former model with an acceptable error. The detection strategy seeks phase-plots topology alteration, induced by defects. In order to test the suitability of the method, leakage in the dashpot was simulated on the lumped model. Results are interesting because changes in phase plots are more appreciable than frequency-shift. Further calculations as well as experimental tests will support future developments of this smart strategy.

Keywords: Pantograph models, phase-plots, structural health monitoring, vibration-based condition monitoring.

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103 Detecting Defects in Textile Fabrics with Optimal Gabor Filters

Authors: K. L. Mak, P. Peng

Abstract:

This paper investigates the problem of automated defect detection for textile fabrics and proposes a new optimal filter design method to solve this problem. Gabor Wavelet Network (GWN) is chosen as the major technique to extract the texture features from textile fabrics. Based on the features extracted, an optimal Gabor filter can be designed. In view of this optimal filter, a new semi-supervised defect detection scheme is proposed, which consists of one real-valued Gabor filter and one smoothing filter. The performance of the scheme is evaluated by using an offline test database with 78 homogeneous textile images. The test results exhibit accurate defect detection with low false alarm, thus showing the effectiveness and robustness of the proposed scheme. To evaluate the detection scheme comprehensively, a prototyped detection system is developed to conduct a real time test. The experiment results obtained confirm the efficiency and effectiveness of the proposed detection scheme.

Keywords: Defect detection, Filtering, Gabor function, Gaborwavelet networks, Textile fabrics.

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102 The Early Stages of the Standardization of Finnish Building Sector

Authors: A. Soikkeli

Abstract:

Early 20th century functionalism aimed at generalising living and rationalising construction, thus laying the foundation for the standardisation of construction components and products. From the 1930s onwards, all measurement and quality instructions for building products, different types of building components, descriptions of working methods complying with advisable building practises, planning, measurement and calculation guidelines, terminology, etc. were called standards. Standardisation was regarded as a necessary prerequisite for the mass production of housing.

This article examines the early stages of standardisation in Finland in the 1940s and 1950s, as reflected on the working history of an individual architect, ErkkiKoiso-Kanttila (1914-2006). In 1950 Koiso-Kanttila was appointed the Head of Design of the Finnish Association of Architects’ Building Standards Committee, a position which he held until 1958. His main responsibilities were the development of the RT Building Information File and compiling of the files.

Keywords: Architecture, Post WWII period, Reconstruction, Standardisation.

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101 Urban Life on the Go: Urban Transformation of Public Space

Authors: E. Zippelius

Abstract:

Urban design aims to provide a stage for public life that, when once brought to life, is right away subject to subtle but continuous transformation. This paper explores such transformations and searches for ways how public life can be reinforced in the case of a housing settlement for the displaced in Nicosia, Cyprus. First, a sound basis of theoretical knowledge is established through literature review, notably the theory of the Production of Space by Henri Lefebvre, exploring its potential and defining key criteria for the following empirical analysis. The analysis is pinpointing the differences between spatial practice, representation of space and spaces of representation as well as their interaction, alliance, or even conflict. In doing so uncertainties, chances and challenges are unraveled that will be consequently linked to practice and action and lead to the formulation of a design strategy. A strategy, though, that does not long for achieving an absolute, finite certainty but understands the three dimensions of space formulated by Lefebvre as equal and space as continuously produced, hence, unfinished.

Keywords: Production of space, public space, urban life, urban transformation.

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100 Wave Interaction with Defects in Pressurized Composite Structures

Authors: R. K. Apalowo, D. Chronopoulos, V. Thierry

Abstract:

A wave finite element (WFE) and finite element (FE) based computational method is presented by which the dispersion properties as well as the wave interaction coefficients for one-dimensional structural system can be predicted. The structural system is discretized as a system comprising a number of waveguides connected by a coupling joint. Uniform nodes are ensured at the interfaces of the coupling element with each waveguide. Then, equilibrium and continuity conditions are enforced at the interfaces. Wave propagation properties of each waveguide are calculated using the WFE method and the coupling element is modelled using the FE method. The scattering of waves through the coupling element, on which damage is modelled, is determined by coupling the FE and WFE models. Furthermore, the central aim is to evaluate the effect of pressurization on the wave dispersion and scattering characteristics of the prestressed structural system compared to that which is not prestressed. Numerical case studies are exhibited for two waveguides coupled through a coupling joint.

Keywords: Finite element, prestressed structures, wave finite element, wave propagation properties, wave scattering coefficients.

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99 Estimating the Effect of Fluid in Pressing Process

Authors: A. Movaghar, R. A. Mahdavinejad

Abstract:

To analyze the effect of various parameters of fluid on the material properties such as surface and depth defects and/or cracks, it is possible to determine the affection of pressure field on these specifications. Stress tensor analysis is also able to determine the points in which the probability of defection creation is more. Besides, from pressure field, it is possible to analyze the affection of various fluid specifications such as viscosity and density on defect created in the material. In this research, the concerned boundary conditions are analyzed first. Then the solution network and stencil used are mentioned. With the determination of relevant equation on the fluid flow between notch and matrix and their discretion according to the governed boundary conditions, these equations can be solved. Finally, with the variation creations on fluid parameters such as density and viscosity, the affection of these variations can be determined on pressure field. In this direction, the flowchart and solution algorithm with their results as vortex and current function contours for two conditions with most applications in pressing process are introduced and discussed.

Keywords: Pressing, notch, matrix, flow function, vortex.

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98 Comparative Study of Indoor Environment in Residential Buildings in Hot Humid Climate of Malaysia

Authors: M. I. Mohd Hafizal, Y. Hiroshi, T. Goto

Abstract:

There-s a lack in understanding the indoor climate of Malaysian residential. The assumption of traditional house could provide the best indoor environment is too good to be true. This research is to understand indoor environment in three types of Malaysian residential and thermo recorder TR72Ui were placed in indoor spaces for measurement. There are huge differences of indoor environment between housing types, and building material helps to control indoor climate. Traditional house indoor climate was similar to the outdoor. Temperature in the bedroom of terrace and town houses were slightly higher than the living room. Indoor temperature was 2oC lower in the rainy season than the hot season. It was hard to control indoor humidity level in traditional house compared with terrace and town house. As for conclusion, town house provides the best thermal environment to the building occupants and can be improved with good roof insulation.

Keywords: Indoor environment, residential, temperature.

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97 Evaluation of Hazardous Status of Avenue Trees in University of Port Harcourt

Authors: F. S. Eguakun, T. C. Nkwor

Abstract:

Trees in the university environment are uniquely position; however, they can also present a millstone to the infrastructure and humans they coexist with. The numerous benefits of trees can be negated due to poor tree health and anthropogenic activities and as such can become hazardous. The study aims at evaluating the hazardous status of avenue trees in University of Port Harcourt. Data were collected from all the avenue trees within the selected major roads in the University. Tree growth variables were measured and health condition of the avenue trees were assessed as an indicator of some structural defects. The hazard status of the avenue trees was determined. Several tree species were used as avenue trees in the University however, Azadirachta indica (81%) was found to be most abundant. The result shows that only 0.3% avenue tree species was found to pose severe harzard in Abuja part of the University. Most avenue trees (55.2%) were rated as medium hazard status. Due to the danger and risk associated with hazardous trees, the study recommends that good and effective management strategies be implemented so as to prevent future damages from trees with small or medium hazard status.

Keywords: Avenue tree, hazard status, inventory, urban.

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96 Real Time Compensation of Machining Errors for Machine Tools NC based on Systematic Dispersion

Authors: M. Rahou, A. Cheikh, F. Sebaa

Abstract:

Manufacturing tolerancing is intended to determine the intermediate geometrical and dimensional states of the part during its manufacturing process. These manufacturing dimensions also serve to satisfy not only the functional requirements given in the definition drawing, but also the manufacturing constraints, for example geometrical defects of the machine, vibration and the wear of the cutting tool. In this paper, an experimental study on the influence of the wear of the cutting tool (systematic dispersions) is explored. This study was carried out on three stages .The first stage allows machining without elimination of dispersions (random, systematic) so the tolerances of manufacture according to total dispersions. In the second stage, the results of the first stage are filtered in such way to obtain the tolerances according to random dispersions. Finally, from the two previous stages, the systematic dispersions are generated. The objective of this study is to model by the least squares method the error of manufacture based on systematic dispersion. Finally, an approach of optimization of the manufacturing tolerances was developed for machining on a CNC machine tool

Keywords: Dispersions, Compensation, modeling, manufacturing Tolerance, machine tool.

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95 Improving TNT Curing Process by Using Infrared Camera

Authors: O. Srihakulung, Y. Soongsumal

Abstract:

Among the chemicals used for ammunition production, TNT (Trinitrotoluene) play a significant role since World War I and II. Various types of military weapon utilize TNT in casting process. However, the TNT casting process for warhead is difficult to control the cooling rate of the liquid TNT. This problem occurs because the casting process lacks the equipment to detect the temperature during the casting procedure This study presents the temperature detected by infrared camera to illustrate the cooling rate and cooling zone of curing, and demonstrates the optimization of TNT condition to reduce the risk of air gap occurred in the warhead which can result in the destruction afterward. Premature initiation of explosive-filled projectiles in response to set-back forces during gunfiring cause by casting defects. Finally the study can help improving the process of the TNT casting. The operators can control the curing of TNT inside the case by rising up the heating rod at the proper time. Consequently this can reduce tremendous time of rework if the air gaps occur and increase strength to lower elastic modulus. Therefore, it can be clearly concluded that the use of Infrared Cameras in this process is another method to improve the casting procedure.

Keywords: Infrared camera, TNT casting, warhead, curing.

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94 Towards Benchmarking English Residential Gas Consumption

Authors: J.Morris, D.Allinson, J.Harrison, K.J. Lomas

Abstract:

The UK Government has emphasized the role of Local Authorities as a key player in its flagship residential energy efficiency strategies, by identifying and targeting areas for energy efficiency improvements. Residential energy consumption in England is characterized by significant geographical variation in energy demand, which makes centralized targeting of areas for energy efficiency intervention difficult. This paper draws on research which aims to understand how demographic, social, economic, urban form and climatic factors influence the geographical variations in English residential gas consumption. The paper reports the findings of a multiple regression model that shows how 64% of the geographical variation in residential gas consumption is accounted for by variations in these factors. Results from this study, after further refinement and validation, can be used by Local Authorities to identify areas within their boundaries that have higher than expected gas consumption, these may be prime targets for energy efficiency initiatives.

Keywords: UK Housing, Heating Energy, Socio-Economics, Statistical Modelling

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93 Enhanced Performance for Support Vector Machines as Multiclass Classifiers in Steel Surface Defect Detection

Authors: Ehsan Amid, Sina Rezaei Aghdam, Hamidreza Amindavar

Abstract:

Steel surface defect detection is essentially one of pattern recognition problems. Support Vector Machines (SVMs) are known as one of the most proper classifiers in this application. In this paper, we introduce a more accurate classification method by using SVMs as our final classifier of the inspection system. In this scheme, multiclass classification task is performed based on the "one-againstone" method and different kernels are utilized for each pair of the classes in multiclass classification of the different defects. In the proposed system, a decision tree is employed in the first stage for two-class classification of the steel surfaces to "defect" and "non-defect", in order to decrease the time complexity. Based on the experimental results, generated from over one thousand images, the proposed multiclass classification scheme is more accurate than the conventional methods and the overall system yields a sufficient performance which can meet the requirements in steel manufacturing.

Keywords: Steel Surface Defect Detection, Support Vector Machines, Kernel Methods.

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92 The Accuracy of the Flight Derivative Estimates Derived from Flight Data

Authors: Jung-hoon Lee, Eung Tai Kim, Byung-hee Chang, In-hee Hwang, Dae-sung Lee

Abstract:

The accuracy of estimated stability and control derivatives of a light aircraft from flight test data were evaluated. The light aircraft, named ChangGong-91, is the first certified aircraft from the Korean government. The output error method, which is a maximum likelihood estimation technique and considers measurement noise only, was used to analyze the aircraft responses measures. The multi-step control inputs were applied in order to excite the short period mode for the longitudinal and Dutch-roll mode for the lateral-directional motion. The estimated stability/control derivatives of Chan Gong-91 were analyzed for the assessment of handling qualities comparing them with those of similar aircraft. The accuracy of the flight derivative estimates derived from flight test measurement was examined in engineering judgment, scatter and Cramer-Rao bound, which turned out to be satisfactory with minor defects..

Keywords: Light Aircraft, Flight Test, Accuracy, Engineering Judgment, Scatter, Cramer-Rao Bound

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91 State-Of-The Art Practices in Bridge Inspection

Authors: Salam R. Yaghi, Saleh Abu Dabous

Abstract:

Government reports and published research have flagged and brought to public attention the deteriorating condition of a large percentage of bridges in Canada and the United States. With the increasing number of deteriorated bridges in the US, Canada, and around the globe, condition assessment techniques of concrete bridges are evolving. Investigation for bridges’ defects such as cracks, spalls, and delamination and their level of severity are the main objectives of condition assessment. Inspection and rehabilitation programs are being implemented to monitor and maintain deteriorated bridge infrastructure. This paper highlights the state-of-the art of current practices being performed for concrete bridge inspection. The information is gathered from the literature and through a distributed questionnaire. The current practices in concrete bridge inspection rely on the use of hummer sounding and chain dragging tests. Non-Destructive Testing (NDT) techniques are not being utilized fully in the process. Nonetheless, they are being partially utilized by the recommendation of the bridge inspector after conducting visual inspection. Lanes are usually closed during the performance of visual inspection and bridge inspection in general.

Keywords: Bridge Inspection, Condition Assessment, questionnaire, Non-Destructive Testing.

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90 A Study on the Planning Criteria of Block-Unit Redevelopment to Improve Residential Environment - Focused on Redevelopment Project in Seoul -

Authors: Hong-Nam Choi, Hyeong-Wook Song, Sungwan Hong, Hong-Kyu Kim

Abstract:

In Korea, elements that decide the quality of residential environment are not only diverse, but show deviation as well. However, people do not consider these elements and instead, they try to settle the uniformed style of residential environment, which focuses on the construction development of apartment housing and business based plans. Recently, block-unit redevelopment is becoming the standout alternative plan of standardize redevelopment projects, but constructions become inefficient because of indefinite planning criteria.

 In conclusion, the following research is about analyzing and categorizing the development method and legal ground of redevelopment project district and plan determinant and applicable standard; the purpose of this study is to become a basis in compatible analysis of planning standards that will happen in the future.

Keywords: Shape Restrictions, Improvement of Reagulation, Diversity of Residential Environment, Classification of Redevelopment Project, Planning Criteria of Redevelopment, Special Architectural District (SAD).

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