Search results for: systems engineering ontology.
537 Strategic Software Development: Productivity Comparisons of General Development Programs
Authors: Craig Comstock, Zhizhong Jiang, Peter Naudé
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Productivity has been one of the major concerns with the increasingly high cost of software development. Choosing the right development language with high productivity is one approach to reduce development costs. Working on the large database with 4106 projects ever developed, we found the factors significant to productivity. After the removal of the effects of other factors on productivity, we compare the productivity differences of the ten general development programs. The study supports the fact that fourth-generation languages are more productive than thirdgeneration languages.
Keywords: Functional point, language, productivity, software engineering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1758536 Experience of the Formation of Professional Competence of Students of IT – Specialties
Authors: B. I. Zhumagaliyev, L. Sh. Balgabayeva, G. S. Nabiyeva, B. A. Tulegenova, P. Oralkhan, B. S. Kalenova, S. S. Akhmetov
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The article describes an approach to build competence in research of Bachelor and Master, which is now an important feature of modern specialist in the field of engineering. We provide an example of methodical teaching methods with the research aspect, including the formulation of the problem, the method of conducting experiments, analysis of the results. Implementation of methods allows the student to better consolidate their knowledge and skills at the same time to get research. Knowledge on the part of the media requires some training in the subject area and teaching methods.
Keywords: Professional competence, its model–specialties, teaching methods, educational technology, decision making.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1581535 Signal Reconstruction Using Cepstrum of Higher Order Statistics
Authors: Adnan Al-Smadi, Mahmoud Smadi
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This paper presents an algorithm for reconstructing phase and magnitude responses of the impulse response when only the output data are available. The system is driven by a zero-mean independent identically distributed (i.i.d) non-Gaussian sequence that is not observed. The additive noise is assumed to be Gaussian. This is an important and essential problem in many practical applications of various science and engineering areas such as biomedical, seismic, and speech processing signals. The method is based on evaluating the bicepstrum of the third-order statistics of the observed output data. Simulations results are presented that demonstrate the performance of this method.
Keywords: Cepstrum, bicepstrum, third order statistics
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2037534 Deployment of Service Quality Characteristics
Authors: Shuki Dror
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This work discusses an innovative methodology for deployment of service quality characteristics. Four groups of organizational features that may influence the quality of services are identified: human resource, technology, planning, and organizational relationships. A House of Service Quality (HOSQ) matrix is built to extract the desired improvement in the service quality characteristics and to translate them into a hierarchy of important organizational features. The Mean Square Error (MSE) criterion enables the pinpointing of the few essential service quality characteristics to be improved as well as selection of the vital organizational features. The method was implemented in an engineering supply enterprise and provides useful information on its vital service dimensions.Keywords: HOQ, organizational features, service quality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1866533 A Study on using N-Pattern Chains of Design Patterns based on Software Quality Metrics
Authors: Niloofar Khedri, Masoud Rahgozar, MahmoudReza Hashemi
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Design patterns describe good solutions to common and reoccurring problems in program design. Applying design patterns in software design and implementation have significant effects on software quality metrics such as flexibility, usability, reusability, scalability and robustness. There is no standard rule for using design patterns. There are some situations that a pattern is applied for a specific problem and this pattern uses another pattern. In this paper, we study the effect of using chain of patterns on software quality metrics.Keywords: Design Patterns, Design patterns' Relationship, Software quality Metrics, Software Engineering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1578532 A Tool for Checking Conformance of UML Specification
Authors: Rosziati Ibrahim, Noraini Ibrahim
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Unified Modeling Language (UML) is a standard language for modeling of a system. UML is used to visually specify the structure and behavior of a system. The system requirements are captured and then converted into UML specification. UML specification uses a set of rules and notations, and diagrams to specify the system requirements. In this paper, we present a tool for developing the UML specification. The tool will ease the use of the notations and diagrams for UML specification as well as increase the understanding and familiarity of the UML specification. The tool will also be able to check the conformance of the diagrams against each other for basic compliance of UML specification.Keywords: Software Engineering, Unified Modeling Language (UML), UML Specification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2207531 Use of Magnesium as a Renewable Energy Source
Authors: Rafayel K. Kostanyan
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The opportunities of use of metallic magnesium as a generator of hydrogen gas, as well as thermal and electric energy is presented in the paper. Various schemes of magnesium application are discussed and power characteristics of corresponding devices are presented. Economic estimation of hydrogen price obtained by different methods is made, including the use of magnesium as a source of hydrogen for transportation in comparison with gasoline. Details and prospects of our new inexpensive technology of magnesium production from magnesium hydroxide and magnesium bearing rocks (which are available worldwide and in Armenia) are analyzed. It is estimated the threshold cost of Mg production at which application of this metal in power engineering is economically justified.
Keywords: Magnesium, power generation, production, renewable energy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2014530 Using LabVIEW Software in an Introductory Residual Current Device Course
Authors: B. Rajkumarsingh, S. Goolaup, A. Galleegadoo
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Laboratory classes in Electrical Engineering are often hampered by safety issues, as students have to work on high voltage lines. One solution is to make use of virtual laboratory simulations, to help students understand the concepts taught in their coursework. In this context, we have conceived and implemented virtual lab experiments in connection with the study of earthing arrangements. In this work, software was developed, which aid student in understanding the working of a residual current device (RCD) in a TT earthing system. Various parameters, such as the earthing resistances, leakage currents and harmonics were included for a TT system with RCD connection.
Keywords: TT system, RCD, LabVIEW, Learning aids.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1884529 Preparation of POMA Nanofibers by Electrospinning and Its Applications in Tissue Engineering
Authors: Lu-Chen Yeh‚ Jui-Ming Yeh
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In this manuscript, we produced neat electrospun poly(o-methoxyaniline) (POMA) fibers and utilized it for applying the growth of neural stem cells. The transparency and morphology of as-prepared POMA fibers was characterized by UV-visible spectroscopy and scanning electron microscopy, respectively. It was found to have no adverse effects on the long-term proliferation of the neural stem cells (NSCs), retained the ability to self-renew, and exhibit multipotentiality. Results of immunofluorescence staining studies confirmed that POMA electrospun fibers could provide a great environment for NSCs and enhance its differentiation.
Keywords: Electrospun, polyaniline, neural stem cell, differentiation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1785528 Simulation of Inverter Fed Induction Motor Drive with LabVIEW
Authors: R. Gunabalan, S. Immanuel Prabakaran, J. Reegan, S. Ganesh
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This paper describes a software approach for modeling inverter fed induction motor drive using Laboratory Virtual Instrument Engineering Workbench (LabVIEW). The reason behind the selection of LabVIEW software is because of its strong graphical interface, flexibility of its programming language combined with built-in tools designed specifically for test, measurement and control. LabVIEW is generally used in most of the applications for data acquisition, test and control. In this paper, inverter and induction motor are modeled using LabVIEW toolkits. Simulation results are presented and are validated.
Keywords: Induction motor, LabVIEW, State model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8575527 The use of a Bespoke Computer Game For Teaching Analogue Electronics
Authors: Olaf Hallan Graven, Dag Andreas Hals Samuelsen
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An implementation of a design for a game based virtual learning environment is described. The game is developed for a course in analogue electronics, and the topic is the design of a power supply. This task can be solved in a number of different ways, with certain constraints, giving the students a certain amount of freedom, although the game is designed not to facilitate trial-and error approach. The use of storytelling and a virtual gaming environment provides the student with the learning material in a MMORPG environment. The game is tested on a group of second year electrical engineering students with good results.Keywords: analogue electronics, e-learning, computer games for learning, virtual reality
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1528526 A Review on Application of Waste Tire in Concrete
Authors: M. A. Yazdi, J. Yang, L. Yihui, H. Su
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The application of recycle waste tires into civil engineering practices, namely asphalt paving mixtures and cementbased materials has been gaining ground across the world. This review summarizes and compares the recent achievements in the area of plain rubberized concrete (PRC), in details. Different treatment methods have been discussed to improve the performance of rubberized Portland cement concrete. The review also includes the effects of size and amount of tire rubbers on mechanical and durability properties of PRC. The microstructure behaviour of the rubberized concrete was detailed.Keywords: Waste rubber aggregates, Microstructure, Treatment methods, Size and content effects.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4664525 Enhanced Data Access Control of Cooperative Environment used for DMU Based Design
Authors: Wei Lifan, Zhang Huaiyu, Yang Yunbin, Li Jia
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Through the analysis of the process digital design based on digital mockup, the fact indicates that a distributed cooperative supporting environment is the foundation conditions to adopt design approach based on DMU. Data access authorization is concerned firstly because the value and sensitivity of the data for the enterprise. The access control for administrators is often rather weak other than business user. So authors established an enhanced system to avoid the administrators accessing the engineering data by potential approach and without authorization. Thus the data security is improved.Keywords: access control, DMU, PLM, virtual prototype.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1463524 Simulation and Analysis of Polyetheretherketone Implants for Diaphysis Femur Fracture
Authors: Abhishek Soni, Bhagat Singh
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In the present work, reverse engineering approach has been used to create a 3D model of a fractured femur diaphysis bone using the computed tomography (CT) scan data. Thereafter, a counter fit fixation plate of polyetheretherketone (PEEK) composite has been designed and analyzed considering static physiological loading conditions. Static stress distribution and deformation analysis of the plate have been performed. From the analysis, it has been found that the stresses and deformation developed are quite low. This implies that these designed fixation plates will be able to provide stable fixation and thus resulting in improved fracture union.
Keywords: Customized implant, deformation, femur diaphysis, stress.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 682523 Scanning Electronic Microscopy for Analysis of the Effects of Surfactants on De-Wrinkling and Dispersion of Graphene
Authors: Kostandinos Katsamangas, B. Ramachandra Bhat, Fawad Inam
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Graphene was dispersed using a tip sonicator and the effect of surfactants were analysed. Sodium Dodecyl Sulphate (SDS) and Polyvinyl Alcohol (PVA) were compared to observe whether or not they had any effect on any de-wrinkling, and secondly whether they aided to achieve better dispersions. There is a huge demand for wrinkle free graphene as this will greatly increase its usefulness in various engineering applications. A comprehensive literature on dewrinkling graphene has been discussed. Low magnification Scanning Electronic Microscopy (SEM) was conducted to assess the quality of graphene de-wrinkling. The utilization of the PVA has significant effect on de-wrinkling whereas SDS had minimal effect on the dewrinkling of graphene.Keywords: De-wrinkling, dispersion, graphene, scanning electron microscopy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1931522 Micropower Composite Nanomaterials Based on Porous Silicon for Renewable Energy Sources
Authors: Alexey P. Antropov, Alexander V. Ragutkin, Nicolay A. Yashtulov
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The original controlled technology for power active nanocomposite membrane-electrode assembly engineering on the basis of porous silicon is presented. The functional nanocomposites were studied by electron microscopy and cyclic voltammetry methods. The application possibility of the obtained nanocomposites as high performance renewable energy sources for micro-power electronic devices is demonstrated.Keywords: Cyclic voltammetry, electron microscopy, nanotechnology, platinum-palladium nanocomposites, porous silicon, power activity, renewable energy sources.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1224521 Numerical Example of Aperiodic Diffraction Grating
Authors: Youssef Khmou, Said Safi, Miloud Frikel
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Diffraction grating is periodic module used in many engineering fields, its geometrical conception gives interesting properties of diffraction and interferences, a uniform and periodic diffraction grating consists of a number of identical apertures that are equally spaced, in this case, the amplitude of intensity distribution in the far field region is generally modulated by diffraction pattern of single aperture. In this paper, we study the case of aperiodic diffraction grating with identical rectangular apertures where theirs coordinates are modeled by square root function, we elaborate a computer simulation comparatively to the periodic array with same length and we discuss the numerical results.Keywords: Diffraction grating, interferences, amplitude modulation, laser.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1080520 Modeling of Cobalt-Chromium-Molybdenum Alloy Implant for Fractured Distal Femur
Authors: Abhishek Soni, Bhagat Singh
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Distal femur fractures are the cause of abnormal gloomy. Several types of surgical treatments have been adopted by the practitioners to restore the fractured region of distal femur. Still within this domain of study, unstable fixation remains a challenge for orthopedists. In the present study, a fixation implant is designed and analyzed under physiological loading conditions for cobalt-chromium-molybdenum alloy (Co-Cr-Mo). It has been found that the stresses and deformation developed are quite low. It means that customized fixation plates will provide stable fixation resulting in improved fracture union.
Keywords: Biomechanical evaluations, customized implant, Co-Cr-Mo alloy, reverse engineering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 760519 A Review on Geomembrane Characteristics and Application in Geotechnical Engineering
Authors: Sandra Ghavam Shirazi, Komeil Valipourian, Mohammad Reza Golhashem
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This paper represents the basic idea and mechanisms associated with the durability of geomembranes and discusses the factors influencing the service life and temperature of geomembrane liners. Geomembrane durability is stated as field performance and laboratory test outcomes under various conditions. Due to the high demand of geomembranes as landfill barriers and their crucial role in sensitive projects, sufficient service life of geomembranes is very important, therefore in this paper, the durability, the effect of temperature on geomembrane and the role of this type of reinforcement in different types of soil will be discussed. Also, the role of geomembrane in the earthquake will be considered in the last part of the paper.
Keywords: Geomembrane, durability temperature soil mechanic.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 932518 Benefits from a SMED Application in a Punching Machine
Authors: Eric Costa, Sara Bragança, Rui Sousa, Anabela Alves
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This paper presents an application of the Single-Minute Exchange of Die (SMED) methodology to a turret punching machine in an elevators company, in Portugal. The work was developed during five months, in the ambit of a master thesis in Industrial Engineering and Management. The Lean Production tool SMED was applied to reduce setup times in order to improve the production flexibility of the machine. The main results obtained were a reduction of 64% in setup time (from 15.1 to 5.4min), 50% in work-in-process amount (from 12.8 to 6.4 days) and 99% in the distance traveled by the operator during the internal period (from 136.7 to 1.7m). These improvements correspond to gains of about €7,315.38 per year.
Keywords: Lean production, setup process, SMED.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4083517 Anthropometric Profile and Its Influence on the Vital Signs of Baja California College Students
Authors: J. A. Lopez, J. E. Olguín, C. Camargo, G. A. Quijano, R. Martínez
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An anthropometric study applied to 1,115 students of the Faculty of Chemical Sciences and Engineering of the Autonomous University of California. Thirteen individual measurements were taken in a sitting position. The results obtained allow forming a reliable anthropometric database for statistical studies and analysis and inferences of specific distributions, so the opinion of experts in occupational medicine recommendations may emit to reduce risks resulting in an alteration of the vital signs during the execution of their school activities. Another use of these analyses is to use them as a reliable reference for future deeper research, to the design of spaces, tools, utensils, workstations, with anthropometric dimensions and ergonomic characteristics suitable to use.
Keywords: Anthropometry, vital signs, students.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2570516 A Case Study: Experiences with Building an Online Exhibition System using Web Services
Authors: Atakan Kurt, Arzu Naiboğlu
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We present an implementation of an Online Exhibition System (OES) web service(s) that reflects our experiences with using web service development packages and software process models. The system provides major functionality that exists in similar packages. While developing such a complex web service, we gained insightful experience (i) in the traditional software development processes: waterfall model and evolutionary development and their fitness to web services development, (ii) in the fitness and effectiveness of a major web services development kit.
Keywords: Web Services, Online Exhibition System, Software Engineering, Waterfall Model, e-business.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2056515 Efficient Design of Distribution Logistics by Using a Model-Based Decision Support System
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The design of distribution logistics has a decisive impact on a company's logistics costs and performance. Hence, such solutions make an essential contribution to corporate success. This article describes a decision support system for analyzing the potential of distribution logistics in terms of logistics costs and performance. In contrast to previous procedures of business process re-engineering (BPR), this method maps distribution logistics holistically under variable distribution structures. Combined with qualitative measures the decision support system will contribute to a more efficient design of distribution logistics.
Keywords: Decision support system distribution logistics, potential analyses, supply chain management.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1823514 Investigation and Perfection of Centrifugal Compressor Stages by CFD Methods
Authors: Y. Galerkin, L. Marenina
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Stator elements «Vane diffuser + crossover + return channel» of stages with different specific speed were investigated by CFD calculations. The regime parameter was introduced to present efficiency and loss coefficient performance of all elements together. Flow structure demonstrated advantages and disadvantages of design. Flow separation in crossovers was eliminated by its shape modification. Efficiency increased visibly. Calculated CFD performances are in acceptable correlation with predicted ones by engineering design method. The information obtained is useful for design method better calibration.
Keywords: Vane diffuser, return channel, crossover, efficiency, loss coefficient, inlet flow angle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2190513 Requirements Gathering for Improved Software Usability and the Potential for Usage-Centred Design
Authors: Kholod J. Alotaibi, Andrew M. Gravell
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Usability is an important software quality that is often neglected at the design stage. Although methods exist to incorporate elements of usability engineering, there is a need for more balanced usability focused methods that can enhance the experience of software usability for users. In this regard, the potential for Usage-Centred Design is explored with respect to requirements gathering and is shown to lead to high software usability besides other benefits. It achieves this through its focus on usage, defining essential use cases, by conducting task modeling, encouraging user collaboration, refining requirements, and so on. The requirements gathering process in UgCD is described in detail.
Keywords: Requirements gathering, Usability, Usage-Centred Design.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1949512 Rapid Prototyping Applications in Various Field of Engineering and Technology
Authors: R. Kumaravelan, V. C. Sathish Gandhi, S. Ramesh, M. Venkatesan
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In the product design and development process, the prototyping or model making is one of the important step to finalize a product which helps in conceptualization of a design. Rapid Prototyping (RP) is layer-by-layer material deposition started during early 1980s with the enormous growth in Computer Aided Design and Manufacturing (CAD/CAM) technologies. The edges and surfaces of a complex solid model and their information are used for defining a product which is further manufactured as a finished product by CNC machining. This paper provides a better platform for researchers, new learners and product manufacturers for various applications of RP models. Subsequently it creates awareness among the peoples of recently developing RP method of manufacturing in product design, developments and its applications.
Keywords: Prototyping, layer-by-layer, CAD/CAM, product design.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8175511 A New Nonlinear PID Controller and its Parameter Design
Authors: Yongping Ren, Zongli Li, Fan Zhang
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A new nonlinear PID controller and its stability analysis are presented in this paper. A nonlinear function is deduced from the similarities between the control effort and the electric-field effect of a capacitor. The conventional linear PID controller can be modified into a nonlinear one by this function. To analyze the stability of the nonlinear PID controlled system, an idea of energy equivalence is adapted to avoid the conservativeness which is usually arisen from some traditional theorems and Criterions. The energy equivalence is naturally related with the conceptions of Passivity and T-Passivity. As a result, an engineering guideline for the parameter design of the nonlinear PID controller is obtained. An inverted pendulum system is tested to verify the nonlinear PID control scheme.Keywords: Nonlinear PID controller, stability, gain equivalence, dissipative, T-Passivity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3176510 Towards a Suitable and Systematic Approach for Component Based Software Development
Authors: Kuljit Kaur, Parminder Kaur, Jaspreet Bedi, Hardeep Singh
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Software crisis refers to the situation in which the developers are not able to complete the projects within time and budget constraints and moreover these overscheduled and over budget projects are of low quality as well. Several methodologies have been adopted form time to time to overcome this situation and now in the focus is component based software engineering. In this approach, emphasis is on reuse of already existing software artifacts. But the results can not be achieved just by preaching the principles; they need to be practiced as well. This paper highlights some of the very basic elements of this approach, which has to be in place to get the desired goals of high quality, low cost with shorter time-to-market software products.Keywords: Component Model, Software Components, SoftwareRepository, Process Models.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1765509 Analysis of Rubber Waste Utilization at Pandora Production Company Limited
Authors: S. Pechpoothong, M. Kopystecki
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The eco-efficient use of “waste" makes sense from economic, social, and environmental perspectives. By efficiency diverting “waste" products back into useful and/or profitable inputs, industries and entire societies can reap the benefits of improved financial profit, decreased environmental degradation, and overall well-being of humanity. In this project, several material flows at Company Limited were investigated. Principles of "industrial ecology" were applied to improve the management of waste rubbers that are used in the jewelry manufacturing process. complete this project, a brief engineering analysis stream, and investigated eco-efficient principles for more efficient handling of the materials and wastes were conducted, and the result were used to propose implementation strategies.Keywords: Rubber, ecology, waste.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3824508 Local Mechanical Analysis of Arch Foot of Space Y-Beam Arch Bridge
Authors: Cao Ziyuan, Luo Xuan
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To study the local force characteristics of a spatial Y-arch bridge, a medium-bearing spatial Y-arch bridge is used as the object of study, and the finite element software FEA is used to establish a spatial finite element model and analyze the force conditions of the arch legs under different most unfavorable loading conditions. It is found that the forces on the arch foot under different conditions are mainly in the longitudinal direction and transverse direction, which should be considered for strengthening. The research results can provide reference for the design and construction of the same type of bridge.
Keywords: Bridge engineering, special-shaped arch bridge, mechanical properties, local analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 442