Search results for: multi-criteria decision process
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 17579

Search results for: multi-criteria decision process

15419 Numerical Design and Characterization of MOVPE Grown Nitride Based Semiconductors

Authors: J. Skibinski, P. Caban, T. Wejrzanowski, K. J. Kurzydlowski

Abstract:

In the present study numerical simulations of epitaxial growth of gallium nitride in Metal Organic Vapor Phase Epitaxy reactor AIX-200/4RF-S are addressed. The aim of this study was to design the optimal fluid flow and thermal conditions for obtaining the most homogeneous product. Since there are many agents influencing reactions on the crystal growth area such as temperature, pressure, gas flow or reactor geometry, it is difficult to design optimal process. Variations of process pressure and hydrogen mass flow rates have been considered. According to the fact that it’s impossible to determine experimentally the exact distribution of heat and mass transfer inside the reactor during crystal growth, detailed 3D modeling has been used to get an insight of the process conditions. Numerical simulations allow to understand the epitaxial process by calculation of heat and mass transfer distribution during growth of gallium nitride. Including chemical reactions in the numerical model allows to calculate the growth rate of the substrate. The present approach has been applied to enhance the performance of AIX-200/4RF-S reactor.

Keywords: computational fluid dynamics, finite volume method, epitaxial growth, gallium nitride

Procedia PDF Downloads 441
15418 Development on the Modeling Driven Architecture

Authors: Sahar Shahsavaripour Ghazanfarpour

Abstract:

As our daily life depends on quality of built services by systems and using devices in our environment; so education and model of software′s quality will be so important. By daily growth in software′s systems and using them so much, progressing process and requirements′ evaluation in primary level of progress especially architecture level in software get more important. Modern driver architecture changes an in dependent model of a level into some specific models that their purpose is reducing number of software changes into an executive model. Process of designing software engineering is mid-automated. The needed quality attribute in designing architecture and quality attribute in representation are in architecture models. The main problem is the relationship between needs, and elements in some aspect with implicit models and input sources in process. It’s because there is no detection ability. The MART profile is use to describe real-time properties and perform plat form modeling.

Keywords: MDA, DW, OMG, UML, AKB, software architecture, ontology, evaluation

Procedia PDF Downloads 479
15417 Application of Rapid Prototyping to Create Additive Prototype Using Computer System

Authors: Meftah O. Bashir, Fatma A. Karkory

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Rapid prototyping is a new group of manufacturing processes, which allows fabrication of physical of any complexity using a layer by layer deposition technique directly from a computer system. The rapid prototyping process greatly reduces the time and cost necessary to bring a new product to market. The prototypes made by these systems are used in a range of industrial application including design evaluation, verification, testing, and as patterns for casting processes. These processes employ a variety of materials and mechanisms to build up the layers to build the part. The present work was to build a FDM prototyping machine that could control the X-Y motion and material deposition, to generate two-dimensional and three-dimensional complex shapes. This study focused on the deposition of wax material. This work was to find out the properties of the wax materials used in this work in order to enable better control of the FDM process. This study will look at the integration of a computer controlled electro-mechanical system with the traditional FDM additive prototyping process. The characteristics of the wax were also analysed in order to optimize the model production process. These included wax phase change temperature, wax viscosity and wax droplet shape during processing.

Keywords: rapid prototyping, wax, manufacturing processes, shape

Procedia PDF Downloads 447
15416 The Effect of Bath Composition for Hot-Dip Aluminizing of AISI 4140 Steel

Authors: Aptullah Karakas, Murat Baydogan

Abstract:

Hot-dip aluminizing (HDA) is one of the several aluminizing methods to form a wear-, corrosion- and oxidation-resistant aluminide layers on the surface. In this method, the substrate is dipped into a molten aluminum bath, hold in the bath for several minutes, and cooled down to the room temperature in air. A subsequent annealing after the HDA process is generally performed. The main advantage of HDA is its very low investment cost in comparison with other aluminizing methods such as chemical vapor deposition (CVD), pack aluminizing and metalizing. In the HDA process, Al or Al-Si molten baths are mostly used. However, in this study, three different Al alloys such as Al4043 (Al-Mg), Al5356 (Al-Si) and Al7020 (Al-Zn) were used as the molten bath in order to see their effects on morphological and mechanical properties of the resulting aluminide layers. AISI 4140 low alloyed steel was used as the substrate. Parameters of the HDA process were bath composition, bath temperature, and dipping time. These parameters were considered within a Taguchi L9 orthogonal array. After the HDA process and subsequent diffusion annealing, coating thickness measurement, microstructural analysis and hardness measurement of the aluminide layers were conducted. The optimum process parameters were evaluated according to coating morphology, such as cracks, Kirkendall porosity and hardness of the coatings. According to the results, smooth and clean aluminide layer with less Kirkendall porosity and cracks were observed on the sample, which was aluminized in the molten Al7020 bath at 700 C for 10 minutes and subsequently diffusion annealed at 750 C. Hardness of the aluminide layer was in between 1100-1300 HV and the coating thickness was approximately 400 µm. The results were promising such that a hard and thick aluminide layer with less Kirkendall porosity and cracks could be formed. It is, therefore, concluded that Al7020 bath may be used in the HDA process of AISI 4140 steel substrate.

Keywords: hot-dip aluminizing, microstructure, hardness measurement, diffusion annealing

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15415 [Keynote Talk]: Pragmatic Leadership in School Organization and Research in Physical Education Professional Development

Authors: Ellie Abdi

Abstract:

This paper is a review of a recently published book (April 2018) by Dr. Ellie Abdi. The book divides into two sections of 1) leadership in school organization and 2) pragmatic research in physical education professional development. The first part of the book explores school organizational development in terms of 1) communication development, 2) community development, and 3) decision making development. It concludes to acknowledge that decision making is the heart of educational management. This is while communication and community are essential to the development of the school organization. The role of a leader in a professional learning community (PLC) is acknowledged with the organizational development plan and moves onto 5 overall objectives of a professional development plan. It clarifies that professional learning community (PLC) benefits both students and professionals in education. Furthermore, professional development needs to be involved in opportunities to value diversity and foundations of learning, in addition to search for veteran teachers who offer a rich combination of experience and perspective. School educational platform in terms of teacher training in physical education is discussed in the second part. The book reviews that well-designed programs are powerful and constructive ways to identify the strength and weaknesses of teachers. Post-positivism, constructivism, advocacy/participatory, and pragmatism in teacher education are also disclosed. The book specifically unfolds pragmatic research in professional development of physical education. It provides researchers, doctoral, and masters level students with defined examples. In summary, the book shows how appropriate it is when many different traditions are displayed in a pragmatic way, following the stages of research from development to dissemination.

Keywords: leadership, physical education, pragmatic, professional development

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15414 An Experimental Study to Investigate the Behaviour of Torque Fluctuation of Crossflow Turbines Operating in an Open Channel

Authors: Sunil Kumar Singal, Manoj Sood, Upendra Bajpai

Abstract:

Instream technology is the upcoming sustainable approach in the hydro sector for energy harnessing. With well-known cross-sections and regulated supply, open channels are the most prominent locations for the installation of hydrokinetic turbines. The fluctuation in generated torque varies with site condition (flow depth and flow velocity), as well as with the type of turbine. The present experimental study aims to investigate the torque/power fluctuations of crossflow hydrokinetic turbines operating at different flow velocities and water depths. The flow velocity is varied from 1.0 m/s to 2.0 m/s. The complete assembly includes an open channel having dimensions of 0.3 m (depth) x 0.71 m (width) x 4.5 m (length), along with a lifting mechanism for varying the channel slope, a digital transducer for monitoring the torque, power, and rpm, a digital handheld water velocity meter for measuring the flow velocity. Further, a time series of torque, power, and rpm is plotted for a duration of 30 minutes showing the continuous operation of the turbine. A comparison of Savonius, Darrieus, and their improved twisted and helical blades is also presented in the study. A correlation has also been developed for assessing the hydropower generation from the installed turbine. The developed correlations will be very useful in the decision-making process for development at a site.

Keywords: darrieus turbine, flow velocity, open channel, savoinus turbine, water depth, hydropower

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15413 Stochastic Optimization of a Vendor-Managed Inventory Problem in a Two-Echelon Supply Chain

Authors: Bita Payami-Shabestari, Dariush Eslami

Abstract:

The purpose of this paper is to develop a multi-product economic production quantity model under vendor management inventory policy and restrictions including limited warehouse space, budget, and number of orders, average shortage time and maximum permissible shortage. Since the “costs” cannot be predicted with certainty, it is assumed that data behave under uncertain environment. The problem is first formulated into the framework of a bi-objective of multi-product economic production quantity model. Then, the problem is solved with three multi-objective decision-making (MODM) methods. Then following this, three methods had been compared on information on the optimal value of the two objective functions and the central processing unit (CPU) time with the statistical analysis method and the multi-attribute decision-making (MADM). The results are compared with statistical analysis method and the MADM. The results of the study demonstrate that augmented-constraint in terms of optimal value of the two objective functions and the CPU time perform better than global criteria, and goal programming. Sensitivity analysis is done to illustrate the effect of parameter variations on the optimal solution. The contribution of this research is the use of random costs data in developing a multi-product economic production quantity model under vendor management inventory policy with several constraints.

Keywords: economic production quantity, random cost, supply chain management, vendor-managed inventory

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15412 Early-Stage Venture Investment Model: Evidence from Saudi Arabia

Authors: Tibah Alharbi, Renzo Cordina, David Power

Abstract:

Relatively few studies have explored how venture capitalist investors (VCs) make investment decisions and the information they rely on when taking an equity stake in an investee company. In addition, little is known about how much investors monitor start-ups after the decision to invest has been made. The VC scene in the US or European context is understood better than that of developing countries such as those in the Middle East. Although some differences among VC investors have been identified, the reasons behind such differences have not been fully explored – especially in a country such as Saudi Arabia. Therefore, this research seeks to understand the impact of external factors on the VC investor’ behaviour. The unique cultural and legal environments in the Kingdom of Saudi Arabia, the growing VC sector in the country, and the increasing importance attached to start-ups under the Saudi Government’s Vision 2030 program make such an investigation timely. Ascertaining the perceptions of VC investors in such a context will provide a deeper understanding of the determinants of VC investment in a novel setting. Using semi-structured interviews with over 20 participants, the research explores the structure of VC funds, the cycle of the VC investment in a start-up from the sourcing of deals, the screening and evaluation of such deals, the closing of such deals, and finally, the monitoring of such investments before the decision to exit such deals at the appropriate time. The results show some similarities to the VC model, which characterizes such investment in the US and Europe, but several differences emerge given the unique cultural and legal settings within the Kingdom. The results provide an in-depth understanding of the VC investors’ mindset relative to the existing studies in the literature.

Keywords: exit, monitoring, start-ups, venture capital

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15411 Application of FT-NIR Spectroscopy and Electronic Nose in On-line Monitoring of Dough Proofing

Authors: Madhuresh Dwivedi, Navneet Singh Deora, Aastha Deswal, H. N. Mishra

Abstract:

FT-NIR spectroscopy and electronic nose was used to study the kinetics of dough proofing. Spectroscopy was conducted with an optic probe in the diffuse reflectance mode. The dough leavening was carried out at different temperatures (25 and 35°C) and constant RH (80%). Spectra were collected in the range of wave numbers from 12,000 to 4,000 cm-1 directly on the samples, every 5 min during proofing, up to 2 hours. NIR spectra were corrected for scatter effect and second order derivatization was done to transform the spectra. Principal component analysis (PCA) was applied for the leavening process and process kinetics was calculated. PCA was performed on data set and loadings were calculated. For leavening, four absorption zones (8,950-8,850, 7,200-6,800, 5,250-5,150 and 4,700-4,250 cm-1) were involved in describing the process. Simultaneously electronic nose was also used for understanding the development of odour compounds during fermentation. The electronic nose was able to differential the sample on the basis of aroma generation at different time during fermentation. In order to rapidly differentiate samples based on odor, a Principal component analysis is performed and successfully demonstrated in this study. The result suggests that electronic nose and FT-NIR spectroscopy can be utilized for the online quality control of the fermentation process during leavening of bread dough.

Keywords: FT-NIR, dough, e-nose, proofing, principal component analysis

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15410 Exploring Alignability Effects and the Role of Information Structure in Promoting Uptake of Energy Efficient Technologies

Authors: Rebecca Hafner, David Elmes, Daniel Read

Abstract:

The current research applies decision-making theory to the problem of increasing uptake of energy efficient technologies in the market place, where uptake is currently slower than one might predict following rational choice models. We apply the alignable/non-alignable features effect and explore the impact of varying information structure on the consumers’ preference for standard versus energy efficient technologies. In two studies we present participants with a choice between similar (boiler vs. boiler) vs. dissimilar (boiler vs. heat pump) technologies, described by a list of alignable and non-alignable attributes. In study One there is a preference for alignability when options are similar; an effect mediated by an increased tendency to infer missing information is the same. No effects of alignability on preference are found when options differ. One explanation for this split-shift in attentional focus is a change in construal levels potentially induced by the added consideration of environmental concern. Study two was designed to explore the interplay between alignability and construal level in greater detail. We manipulated construal level via a thought prime task prior to taking part in the same heating systems choice task, and find that there is a general preference for non-alignability, regardless of option type. We draw theoretical and applied implications for the type of information structure best suited for the promotion of energy efficient technologies.

Keywords: alignability effects, decision making, energy-efficient technologies, sustainable behaviour change

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15409 Intensification of Heat Transfer in Magnetically Assisted Reactor

Authors: Dawid Sołoducha, Tomasz Borowski, Marian Kordas, Rafał Rakoczy

Abstract:

The magnetic field in the past few years became an important part of many studies. Magnetic field (MF) may be used to affect the process in many ways; for example, it can be used as a factor to stabilize the system. We can use MF to steer the operation, to activate or inhibit the process, or even to affect the vital activity of microorganisms. Using various types of magnetic field generators is always connected with the delivery of some heat to the system. Heat transfer is a very important phenomenon; it can influence the process positively and negatively, so it’s necessary to measure heat stream transferred from the place of generation and prevent negative influence on the operation. The aim of the presented work was to apply various types of magnetic fields and to measure heat transfer phenomena. The results were obtained by continuous measurement at several measuring points with temperature probes. Results were compilated in the form of temperature profiles. The study investigated the undetermined heat transfer in a custom system equipped with a magnetic field generator. Experimental investigations are provided for the explanation of the influence of the various type of magnetic fields on the heat transfer process. The tested processes are described by means of the criteria which defined heat transfer intensification under the action of magnetic field.

Keywords: heat transfer, magnetic field, undetermined heat transfer, temperature profile

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15408 Optimizing and Evaluating Performance Quality Control of the Production Process of Disposable Essentials Using Approach Vague Goal Programming

Authors: Hadi Gholizadeh, Ali Tajdin

Abstract:

To have effective production planning, it is necessary to control the quality of processes. This paper aims at improving the performance of the disposable essentials process using statistical quality control and goal programming in a vague environment. That is expressed uncertainty because there is always a measurement error in the real world. Therefore, in this study, the conditions are examined in a vague environment that is a distance-based environment. The disposable essentials process in Kach Company was studied. Statistical control tools were used to characterize the existing process for four factor responses including the average of disposable glasses’ weights, heights, crater diameters, and volumes. Goal programming was then utilized to find the combination of optimal factors setting in a vague environment which is measured to apply uncertainty of the initial information when some of the parameters of the models are vague; also, the fuzzy regression model is used to predict the responses of the four described factors. Optimization results show that the process capability index values for disposable glasses’ average of weights, heights, crater diameters and volumes were improved. Such increasing the quality of the products and reducing the waste, which will reduce the cost of the finished product, and ultimately will bring customer satisfaction, and this satisfaction, will mean increased sales.

Keywords: goal programming, quality control, vague environment, disposable glasses’ optimization, fuzzy regression

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15407 A Highly Efficient Broadcast Algorithm for Computer Networks

Authors: Ganesh Nandakumaran, Mehmet Karaata

Abstract:

A wave is a distributed execution, often made up of a broadcast phase followed by a feedback phase, requiring the participation of all the system processes before a particular event called decision is taken. Wave algorithms with one initiator such as the 1-wave algorithm have been shown to be very efficient for broadcasting messages in tree networks. Extensions of this algorithm broadcasting a sequence of waves using a single initiator have been implemented in algorithms such as the m-wave algorithm. However as the network size increases, having a single initiator adversely affects the message delivery times to nodes further away from the initiator. As a remedy, broadcast waves can be allowed to be initiated by multiple initiator nodes distributed across the network to reduce the completion time of broadcasts. These waves initiated by one or more initiator processes form a collection of waves covering the entire network. Solutions to global-snapshots, distributed broadcast and various synchronization problems can be solved efficiently using waves with multiple concurrent initiators. In this paper, we propose the first stabilizing multi-wave sequence algorithm implementing waves started by multiple initiator processes such that every process in the network receives at least one sequence of broadcasts. Due to being stabilizing, the proposed algorithm can withstand transient faults and do not require initialization. We view a fault as a transient fault if it perturbs the configuration of the system but not its program.

Keywords: distributed computing, multi-node broadcast, propagation of information with feedback and cleaning (PFC), stabilization, wave algorithms

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15406 A Comparison of Neural Network and DOE-Regression Analysis for Predicting Resource Consumption of Manufacturing Processes

Authors: Frank Kuebler, Rolf Steinhilper

Abstract:

Artificial neural networks (ANN) as well as Design of Experiments (DOE) based regression analysis (RA) are mainly used for modeling of complex systems. Both methodologies are commonly applied in process and quality control of manufacturing processes. Due to the fact that resource efficiency has become a critical concern for manufacturing companies, these models needs to be extended to predict resource-consumption of manufacturing processes. This paper describes an approach to use neural networks as well as DOE based regression analysis for predicting resource consumption of manufacturing processes and gives a comparison of the achievable results based on an industrial case study of a turning process.

Keywords: artificial neural network, design of experiments, regression analysis, resource efficiency, manufacturing process

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15405 Simulation of Die Casting Process in an Industrial Helical Gearbox Flange Die

Authors: Mehdi Modabberifar, Behrouz Raad, Bahman Mirzakhani

Abstract:

Flanges are widely used for connecting valves, pipes and other industrial devices such as gearboxes. Method of producing a flange has a considerable impact on the manner of their involvement with the industrial engines and gearboxes. By Using die casting instead of sand casting and machining for manufacturing flanges, production speed and dimensional accuracy of the parts increases. Also, in die casting, obtained dimensions are close to final dimensions and hence the need for machining flanges after die casting process decreases which makes a significant savings in raw materials and improves the mechanical properties of flanges. In this paper, a typical die of an industrial helical gearbox flange (size ISO 50) was designed and die casting process for producing this type of flange was simulated using ProCAST software. The results of simulation were used for optimizing die design. Finally, using the results of the analysis, optimized die was built.

Keywords: die casting, finite element, flange, helical gearbox

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15404 Spatial Information and Urbanizing Futures

Authors: Mohammad Talei, Neda Ranjbar Nosheri, Reza Kazemi Gorzadini

Abstract:

Today municipalities are searching for the new tools for increasing the public participation in different levels of urban planning. This approach of urban planning involves the community in planning process using participatory approaches instead of the long traditional top-down planning methods. These tools can be used to obtain the particular problems of urban furniture form the residents’ point of view. One of the tools that is designed with this goal is public participation GIS (PPGIS) that enables citizen to record and following up their feeling and spatial knowledge regarding main problems of the city, specifically urban furniture, in the form of maps. However, despite the good intentions of PPGIS, its practical implementation in developing countries faces many problems including the lack of basic supporting infrastructure and services and unavailability of sophisticated public participatory models. In this research we develop a PPGIS using of Web 2 to collect voluntary geodataand to perform spatial analysis based on Spatial OnLine Analytical Processing (SOLAP) and Spatial Data Mining (SDM). These tools provide urban planners with proper informationregarding the type, spatial distribution and the clusters of reported problems. This system is implemented in a case study area in Tehran, Iran and the challenges to make it applicable and its potential for real urban planning have been evaluated. It helps decision makers to better understand, plan and allocate scarce resources for providing most requested urban furniture.

Keywords: PPGIS, spatial information, urbanizing futures, urban planning

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15403 Assessing the Plant Diversity's Quality, Threats and Opportunities for the Support of Sustainable City Development of the City Raipur, India

Authors: Katharina Lapin, Debashis Sanyal

Abstract:

Worldwide urban areas are growing. Urbanization has a great impact on social and economic development and ecosystem services. This global trend of urbanization also has significant impact on habitat and biodiversity. The impact of urbanization on the biodiversity of cities in Europe and North America is well studied, while there is a lack of data from cities in currently fast growing urban areas. Indian cities are expanding. The scientific community and the governmental authorities are facing the ongoing urbanization process as an opportunity for the environment. This case study supports the evaluation of urban biodiversity of the city Raipur in the North-West of India. The aim of this study is to assess the overview of the environmental and ecological implications of urbanization. The collected data and analysis was used to discuss the challenges for the sustainable city development. Vascular plants were chosen as an appropriate indicator for the assessment of local biodiversity changes. On the one hand, the vegetation cover is sensible to anthropogenic influence, and in the other hand, the local species composition is comparable to changes at the regional and national scale, using the plant index of India. Further information of abiotic situation can be gathered with the determination of indicator species. In order to calculate the influence of urbanization on the native plant diversity, the Shannon diversity index H´ was chosen. The Pielou`s pooled quadrate method was used for estimating diversity when a random sample is not expected. It was used to calculate the Pilou´s index of evenness. The estimated species coverage was used for calculating the H´ and J. Pearson correlation was performed to test the relationship between urbanization pattern and plant diversity. Further, a SWOT analysis was used in for analyzing internal and external factors impinging on a decision making process. The city of Raipur (21.25°N 81.63°E) has a population of 1,010,087 inhabitants living in an urban area of 226km², in the district of the Indian state of Chhattisgarh. Within the last decade, the urban area of Raipur increased. The results show that various novel ecosystems exist in the urban area of Raipur. The high amount of native flora is mainly to find at the shore of urban lakes and along the river Karun. These areas of high Biodiversity Index are to protect as urban biodiversity hot spots. The governmental authorities are well informed about the environmental challenges for the sustainable development of the city. Together with the scientific community of the Technical University of Raipur many engineering solutions are discussed for implementation of the future. The case study helped to point out the importance environmental measures that support the ecosystem services of green infrastructure. The fast process of urbanization is difficult to control. Uncontrolled creation of urban housing leads to difficulties in unsustainable use of natural resources. This is the major threat for the urban biodiversity.

Keywords: India, novel ecosystems, plant diversity, urban ecology

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15402 Business Process Management and Organizational Culture in Big Companies: Cross-Country Analysis

Authors: Dalia Suša Vugec

Abstract:

Business process management (BPM) is widely used approach focused on designing, mapping, changing, managing and analyzing business processes of an organization, which eventually leads to better performance and derives many other benefits. Since every organization strives to improve its performance in order to be sustainable and to remain competitive on the market in long-term period, numerous organizations are nowadays adopting and implementing BPM. However, not all organizations are equally successful in that. One of the ways of measuring BPM success is by measuring its maturity by calculating Process Performance Index (PPI) using ten BPM success factors. Still, although BPM is a holistic concept, organizational culture is not taken into consideration in calculating PPI. Hence, aim of this paper is twofold; first, it aims to explore and analyze the current state of BPM success factors within the big organizations from Slovenia, Croatia, and Austria and second, it aims to analyze the structure of organizational culture within the observed companies, focusing on the link with BPM success factors as well. The presented study is based on the results of the questionnaire conducted as the part of the PROSPER project (IP-2014-09-3729) and financed by Croatian Science Foundation. The results of the questionnaire reveal differences in the achieved levels of BPM success factors and therefore BPM maturity in total between the three observed countries. Moreover, the structure of organizational culture across three countries also differs. This paper discusses the revealed differences between countries as well as the link between organizational culture and BPM success factors.

Keywords: business process management, BPM maturity, BPM success factors, organizational culture, process performance index

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15401 Effect of Process Parameters on Mechanical Properties of Friction Stir Welded Aluminium Alloy Joints Using Factorial Design

Authors: Gurjinder Singh, Ankur Gill, Amardeep Singh Kang

Abstract:

In the present work an effort has been made to study the influence of the welding parameters on tensile strength of friction stir welding of aluminum. Three process parameters tool rotation speed, welding speed, and shoulder diameter were selected for the study. Two level factorial design of eight runs was selected for conducting the experiments. The mathematical model was developed from the data obtained. The significance of coefficients and adequacy of developed models were tested by ‘t’ test and ‘F’ test respectively. The effects of process parameters on mechanical properties have been represented in the form of graphs for better understanding.

Keywords: friction stir welding, aluminium alloy, mathematical model, welding speed

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15400 Design of Bayesian MDS Sampling Plan Based on the Process Capability Index

Authors: Davood Shishebori, Mohammad Saber Fallah Nezhad, Sina Seifi

Abstract:

In this paper, a variable multiple dependent state (MDS) sampling plan is developed based on the process capability index using Bayesian approach. The optimal parameters of the developed sampling plan with respect to constraints related to the risk of consumer and producer are presented. Two comparison studies have been done. First, the methods of double sampling model, sampling plan for resubmitted lots and repetitive group sampling (RGS) plan are elaborated and average sample numbers of the developed MDS plan and other classical methods are compared. A comparison study between the developed MDS plan based on Bayesian approach and the exact probability distribution is carried out.

Keywords: MDS sampling plan, RGS plan, sampling plan for resubmitted lots, process capability index (PCI), average sample number (ASN), Bayesian approach

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15399 Parametric and Analysis Study of the Melting in Slabs Heated by a Laminar Heat Transfer Fluid in Downward and Upward Flows

Authors: Radouane Elbahjaoui, Hamid El Qarnia

Abstract:

The present work aims to investigate numerically the thermal and flow characteristics of a rectangular latent heat storage unit (LHSU) during the melting process of a phase change material (PCM). The LHSU consists of a number of vertical and identical plates of PCM separated by rectangular channels. The melting process is initiated when the LHSU is heated by a heat transfer fluid (HTF: water) flowing in channels in a downward or upward direction. The proposed study is motivated by the need to optimize the thermal performance of the LHSU by accelerating the charging process. A mathematical model is developed and a fixed-grid enthalpy formulation is adopted for modeling the melting process coupling with convection-conduction heat transfer. The finite volume method was used for discretization. The obtained numerical results are compared with experimental, analytical and numerical ones found in the literature and reasonable agreement is obtained. Thereafter, the numerical investigations were carried out to highlight the effects of the HTF flow direction and the aspect ratio of the PCM slabs on the heat transfer characteristics and thermal performance enhancement of the LHSU.

Keywords: PCM, TES, LHSU, melting

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15398 Microwave Sanitization of Polyester Fabrics

Authors: K. Haggag, M. Salama, H. El-Sayed

Abstract:

Polyester fabrics were sanitized by exposing them to vaporized water under the influence of conventional heating or microwave irradiation. Hydrogen peroxide was added the humid sanitizing environment as a disinfectant. The said sanitization process was found to be effective towards two types of bacteria, namely Escherichia coli ATCC 2666 (G –ve) and Staphylococcus aureus ATCC 6538 (G +ve). The effect of the sanitization process on some of the inherent properties of polyester fabrics was monitored.

Keywords: polyester, fabric, sanitization, microwave, bacteria

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15397 Estimation of World Steel Production by Process

Authors: Reina Kawase

Abstract:

World GHG emissions should be reduced 50% by 2050 compared with 1990 level. CO2 emission reduction from steel sector, an energy-intensive sector, is essential. To estimate CO2 emission from steel sector in the world, estimation of steel production is required. The world steel production by process is estimated during the period of 2005-2050. The world is divided into aggregated 35 regions. For a steel making process, two kinds of processes are considered; basic oxygen furnace (BOF) and electric arc furnace (EAF). Steel production by process in each region is decided based on a current production capacity, supply-demand balance of steel and scrap, technology innovation of steel making, steel consumption projection, and goods trade. World steel production under moderate countermeasure scenario in 2050 increases by 1.3 times compared with that in 2012. When domestic scrap recycling is promoted, steel production in developed regions increases about 1.5 times. The share in developed regions changes from 34 %(2012) to about 40%(2050). This is because developed regions are main suppliers of scrap. 48-57% of world steel production is produced by EAF. Under the scenario which thinks much of supply-demand balance of steel, steel production in developing regions increases is 1.4 times and is larger than that in developed regions. The share in developing regions, however, is not so different from current level. The increase in steel production by EAF is the largest under the scenario in which supply-demand balance of steel is an important factor. The share reaches 65%.

Keywords: global steel production, production distribution scenario, steel making process, supply-demand balance

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15396 Technology in the Calculation of People Health Level: Design of a Computational Tool

Authors: Sara Herrero Jaén, José María Santamaría García, María Lourdes Jiménez Rodríguez, Jorge Luis Gómez González, Adriana Cercas Duque, Alexandra González Aguna

Abstract:

Background: Health concept has evolved throughout history. The health level is determined by the own individual perception. It is a dynamic process over time so that you can see variations from one moment to the next. In this way, knowing the health of the patients you care for, will facilitate decision making in the treatment of care. Objective: To design a technological tool that calculates the people health level in a sequential way over time. Material and Methods: Deductive methodology through text analysis, extraction and logical knowledge formalization and education with expert group. Studying time: September 2015- actually. Results: A computational tool for the use of health personnel has been designed. It has 11 variables. Each variable can be given a value from 1 to 5, with 1 being the minimum value and 5 being the maximum value. By adding the result of the 11 variables we obtain a magnitude in a certain time, the health level of the person. The health calculator allows to represent people health level at a time, establishing temporal cuts being useful to determine the evolution of the individual over time. Conclusion: The Information and Communication Technologies (ICT) allow training and help in various disciplinary areas. It is important to highlight their relevance in the field of health. Based on the health formalization, care acts can be directed towards some of the propositional elements of the concept above. The care acts will modify the people health level. The health calculator allows the prioritization and prediction of different strategies of health care in hospital units.

Keywords: calculator, care, eHealth, health

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15395 Special Plea That The Prosecutor Does Not Have Title To Prosecute

Authors: Wium de Villiers

Abstract:

Section 106(1)(h) of the South African Criminal Procedure Act 51 of 1977 provides that an accused may enter a special plea that the prosecutor does not have title to prosecute. In a seminal matter (S v Mousa 2021 2 SACR 378 (GJ)) regarding section 106(1)(h), certain interesting legal aspects emerged. The first aspect concerned the meaning of the term “prosecutor”. More specifically, the question arose whether the term included a prosecutor who was previously involved with the matter, as well as the relevant Deputy Director of Public Prosecutions (DDPP) who instituted the prosecution and oversaw the prosecution on behalf of the state. The meaning of the term “title”, and with regard to the conduct of the “prosecutor”, the term “abuse of process,” were also raised and decided. In the paper, the facts, and the arguments in, and the decisions of the court, are discussed critically. The author argue that the intended objection in section 106(1)(h) is not to cure the abuse inflicted by a previous prosecutor or by the DDPP. I point out that the term “title” includes a lack of authority, non-compliance with jurisdictional requirements or absence of locus standi. I also point out that an abuse of process takes place if the process is used for an improper, ulterior or collateral purpose. I also argue that the accused should, instead of relying on section 106(1)(h), have relied on the prior agreement and applied for a permanent stay of prosecution.

Keywords: special plea, prosecutor, title, abuse of process

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15394 Pharmaceutical Scale up for Solid Dosage Forms

Authors: A. Shashank Tiwari, S. P. Mahapatra

Abstract:

Scale-up is defined as the process of increasing batch size. Scale-up of a process viewed as a procedure for applying the same process to different output volumes. There is a subtle difference between these two definitions: batch size enlargement does not always translate into a size increase of the processing volume. In mixing applications, scale-up is indeed concerned with increasing the linear dimensions from the laboratory to the plant size. On the other hand, processes exist (e.g., tableting) where the term ‘scale-up’ simply means enlarging the output by increasing the speed. To complete the picture, one should point out special procedures where an increase of the scale is counterproductive and ‘scale-down’ is required to improve the quality of the product. In moving from Research and Development (R&D) to production scale, it is sometimes essential to have an intermediate batch scale. This is achieved at the so-called pilot scale, which is defined as the manufacturing of drug product by a procedure fully representative of and simulating that used for full manufacturing scale. This scale also makes it possible to produce enough products for clinical testing and to manufacture samples for marketing. However, inserting an intermediate step between R&D and production scales does not, in itself, guarantee a smooth transition. A well-defined process may generate a perfect product both in the laboratory and the pilot plant and then fail quality assurance tests in production.

Keywords: scale up, research, size, batch

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15393 Evaluation of Machine Learning Algorithms and Ensemble Methods for Prediction of Students’ Graduation

Authors: Soha A. Bahanshal, Vaibhav Verdhan, Bayong Kim

Abstract:

Graduation rates at six-year colleges are becoming a more essential indicator for incoming fresh students and for university rankings. Predicting student graduation is extremely beneficial to schools and has a huge potential for targeted intervention. It is important for educational institutions since it enables the development of strategic plans that will assist or improve students' performance in achieving their degrees on time (GOT). A first step and a helping hand in extracting useful information from these data and gaining insights into the prediction of students' progress and performance is offered by machine learning techniques. Data analysis and visualization techniques are applied to understand and interpret the data. The data used for the analysis contains students who have graduated in 6 years in the academic year 2017-2018 for science majors. This analysis can be used to predict the graduation of students in the next academic year. Different Predictive modelings such as logistic regression, decision trees, support vector machines, Random Forest, Naïve Bayes, and KNeighborsClassifier are applied to predict whether a student will graduate. These classifiers were evaluated with k folds of 5. The performance of these classifiers was compared based on accuracy measurement. The results indicated that Ensemble Classifier achieves better accuracy, about 91.12%. This GOT prediction model would hopefully be useful to university administration and academics in developing measures for assisting and boosting students' academic performance and ensuring they graduate on time.

Keywords: prediction, decision trees, machine learning, support vector machine, ensemble model, student graduation, GOT graduate on time

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15392 Preliminary Study of Desiccant Cooling System under Algerian Climates

Authors: N. Hatraf, N. Moummi

Abstract:

The interest in air conditioning using renewable energies is increasing. The thermal energy produced from the solar energy can be converted to useful cooling and heating through the thermochemical or thermophysical processes by using thermally activated energy conversion systems. The ambient air contains so much water that very high dehumidification rates are required. For a continuous dehumidification of the process air, the water adsorbed on the desiccant material has to be removed, which is done by allowing hot air to flow through the desiccant material (regeneration). A solid desiccant cooling system transfers moisture from the inlet air to the silica gel by using two processes: Absorption process and the regeneration process. The main aim of this paper is to study how the dehumidification rate, the generation temperature and many other factors influence the efficiency of a solid desiccant system by using TRNSYS software. The results show that the desiccant system could be used to decrease the humidity rate of the entering air.

Keywords: dehumidification, efficiency, humidity, Trnsys

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15391 Comparison of E-learning and Face-to-Face Learning Models Through the Early Design Stage in Architectural Design Education

Authors: Gülay Dalgıç, Gildis Tachir

Abstract:

Architectural design studios are ambiencein where architecture design is realized as a palpable product in architectural education. In the design studios that the architect candidate will use in the design processthe information, the methods of approaching the design problem, the solution proposals, etc., are set uptogetherwith the studio coordinators. The architectural design process, on the other hand, is complex and uncertain.Candidate architects work in a process that starts with abstre and ill-defined problems. This process starts with the generation of alternative solutions with the help of representation tools, continues with the selection of the appropriate/satisfactory solution from these alternatives, and then ends with the creation of an acceptable design/result product. In the studio ambience, many designs and thought relationships are evaluated, the most important step is the early design phase. In the early design phase, the first steps of converting the information are taken, and converted information is used in the constitution of the first design decisions. This phase, which positively affects the progress of the design process and constitution of the final product, is complex and fuzzy than the other phases of the design process. In this context, the aim of the study is to investigate the effects of face-to-face learning model and e-learning model on the early design phase. In the study, the early design phase was defined by literature research. The data of the defined early design phase criteria were obtained with the feedback graphics created for the architect candidates who performed e-learning in the first year of architectural education and continued their education with the face-to-face learning model. The findings of the data were analyzed with the common graphics program. It is thought that this research will contribute to the establishment of a contemporary architectural design education model by reflecting the evaluation of the data and results on architectural education.

Keywords: education modeling, architecture education, design education, design process

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15390 Modeling of Combustion Process in the Piston Aircraft Engine Using a MCFM-3Z Model

Authors: Marcin Szlachetka, Konrad Pietrykowski

Abstract:

Modeling of a combustion process in a 9-cylinder aircraft engine is presented. The simulations of the combustion process in the IC engine have provided the information on the spatial and time distributions of selected quantities within the combustion chamber of the engine. The numerical analysis results have been compared with the results of indication process of the engine on the test stand. Modeling of combustion process an auto-ignited IC engine in the AVL Fire was carried out within the study. For the calculations, a ECFM-3Z model was used. Verification of simulation results was carried out by comparison of the pressure in the cylinder. The courses of indicated pressure, obtained from the simulations and during the engine tests mounted on a test stand were compared. The engine was braked by the propeller, which results in an adequate external power characteristics. The test object is a modified ASz-62IR engine with the injection system. The engine was running at take-off power. To check the optimum ignition timing regarding power, calculations, tests were performed for 7 different moments of ignition. The analyses of temperature distribution in the cylinder depending on the moments of ignition were carried out. Additional the course of pressure in the cylinder at different angles of ignition delays of the second spark plug were examined. The swirling of the mixture in the combustion chamber was also analysed. It has been shown that the largest vortexes occur in the middle of the chamber, and gets smaller, closer to the combustion chamber walls. This work has been financed by the Polish National Centre for Research and Development, INNOLOT, under Grant Agreement No. INNOLOT/I/1/NCBR/2013.

Keywords: CFD, combustion, internal combustion engine, aircraft engine

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