Search results for: Process Mining
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 16091

Search results for: Process Mining

14921 Development of Broad Spectrum Nitrilase Biocatalysts and Bioprocesses for Nitrile Biotransformation

Authors: Avinash Vellore Sunder, Shikha Shah, Pramod P. Wangikar

Abstract:

The enzymatic conversion of nitriles to carboxylic acids by nitrilases has gained significance in the green synthesis of several pharmaceutical precursors and fine chemicals. While nitrilases have been characterized from different sources, the industrial application requires the identification of nitrilases that possess higher substrate tolerance, wider specificity and better thermostability, along with the development of an efficient bioprocess for producing large amounts of nitrilase. To produce large amounts of nitrilase, we developed a fed-batch fermentation process on defined media for the high cell density cultivation of E. coli cells expressing the well-studied nitrilase from Alcaligenes fecalis. A DO-stat feeding approach was employed combined with an optimized post-induction strategy to achieve nitrilase titer of 2.5*105 U/l and 78 g/l dry cell weight. We also identified 16 novel nitrilase sequences from genome mining and analysis of substrate binding residues. The nitrilases were expressed in E. coli and their biocatalytic potential was evaluated on a panel of 22 industrially relevant nitrile substrates using high-throughput screening and HPLC analysis. Nine nitrilases were identified to exhibit high activity on structurally diverse nitriles including aliphatic and aromatic dinitriles, heterocyclic, -hydroxy and -keto nitriles. With fed-batch biotransformation, whole-cell Zobelia galactanivorans nitrilase achieved yields of 2.4 M nicotinic acid and 1.8 M isonicotinic acid from 3-cyanopyridine and 4-cyanopyridine respectively within 5 h, while Cupravidus necator nitrilase enantioselectively converted 740 mM mandelonitrile to (R)–mandelic acid. The nitrilase from Achromobacter insolitus could hydrolyze 542 mM iminodiacetonitrile in 1 h. The availability of highly active nitrilases along with bioprocesses for enzyme production expands the toolbox for industrial biocatalysis.

Keywords: biocatalysis, isonicotinic acid, iminodiacetic acid, mandelic acid, nitrilase

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14920 Gentrification and Its Impact on Urbanization in India

Authors: Swapnil Vidhate, Anupama Sharma

Abstract:

At present the world is experiencing an extraordinary rate of urbanization. India is also in a major phase of urbanization. Gentrification is being practiced in India much later compared to western countries as a strategy for urban renewal. The urban fabric in Indian context is composed of multiple layers in it. Thus, the process of gentrification has different typologies, views and impacts in Indian context. It is a curative concept to restructure the declined areas of the city. But it has more negative views compared to positive due to the concerns in the process in India. The paper brings out the impacts of gentrification and concerns related with the process in Indian context with a case example of core city.

Keywords: urbanization, urban renewal, gentrification, restructure, core city

Procedia PDF Downloads 758
14919 A Cost-Effective Evaluation of Proper Control Process of Air-Cooled Heat Exchanger

Authors: Ali Ghobadi, Eisa Bakhoda, Hamid R. Javdan

Abstract:

One of the key factors in air cooled heat exchangers operation is the proper control of process stream outlet temperature. In this study, performances of two different air cooled heat exchangers have been considered, one of them condenses Propane and the other one cools LPG streams. In order to predict operation of these air coolers at different operating conditions. The results of simulations were applied for both economical evaluations and operational considerations for using convenient air cooler control system. In this paper, using On-Off fans method and installing variable speed drivers have been studied. Finally, the appropriate methods for controlling outlet temperature of process fluid streams as well as saving energy consumption were proposed. Using On-Off method for controlling studied Propane condenser by multiple fans is proper; while controlling LPG air cooler with lesser fans by means of two variable speed drivers is economically convenient.

Keywords: air cooled heat exchanger, simulation, economical evaluation, energy, process control

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14918 The Effects of the Waste Plastic Modification of the Asphalt Mixture on the Permanent Deformation

Authors: Soheil Heydari, Ailar Hajimohammadi, Nasser Khalili

Abstract:

The application of plastic waste for asphalt modification is a sustainable strategy to deal with the enormous plastic waste generated each year and enhance the properties of asphalt. The modification is either practiced by the dry process or the wet process. In the dry process, plastics are added straight into the asphalt mixture, and in the wet process, they are mixed and digested into bitumen. In this article, the effects of plastic inclusion in asphalt mixture, through the dry process, on the permanent deformation of the asphalt are investigated. The main waste plastics that are usually used in asphalt modification are taken into account, which is linear, low-density polyethylene, low-density polyethylene, high-density polyethylene, and polypropylene. Also, to simulate a plastic waste stream, different grades of each virgin plastic are mixed and used. For instance, four different grades of polypropylene are mixed and used as representative of polypropylene. A precisely designed mixing condition is considered to dry-mix the plastics into the mixture such that the polymer was melted and modified by the later introduced binder. In this mixing process, plastics are first added to the hot aggregates and mixed three times in different time intervals, then bitumen is introduced, and the whole mixture is mixed three times in fifteen minutes intervals. Marshall specimens were manufactured, and dynamic creep tests were conducted to evaluate the effects of modification on the permanent deformation of the asphalt mixture. Dynamic creep is a common repeated loading test conducted at different stress levels and temperatures. Loading cycles are applied to the AC specimen until failure occurs; with the amount of deformation constantly recorded, the cumulative, permanent strain is determined and reported as a function of the number of cycles. The results of this study showed that the dry inclusion of the waste plastics is very effective in enhancing the resistance against permanent deformation of the mixture. However, the mixing process must be precisely engineered to melt the plastics, and a homogenous mixture is achieved.

Keywords: permanent deformation, waste plastics, low-density polyethene, high-density polyethene, polypropylene, linear low-density polyethene, dry process

Procedia PDF Downloads 89
14917 Multiparametric Optimization of Water Treatment Process for Thermal Power Plants

Authors: Balgaisha Mukanova, Natalya Glazyrina, Sergey Glazyrin

Abstract:

The formulated problem of optimization of the technological process of water treatment for thermal power plants is considered in this article. The problem is of multiparametric nature. To optimize the process, namely, reduce the amount of waste water, a new technology was developed to reuse such water. A mathematical model of the technology of wastewater reuse was developed. Optimization parameters were determined. The model consists of a material balance equation, an equation describing the kinetics of ion exchange for the non-equilibrium case and an equation for the ion exchange isotherm. The material balance equation includes a nonlinear term that depends on the kinetics of ion exchange. A direct problem of calculating the impurity concentration at the outlet of the water treatment plant was numerically solved. The direct problem was approximated by an implicit point-to-point computation difference scheme. The inverse problem was formulated as relates to determination of the parameters of the mathematical model of the water treatment plant operating in non-equilibrium conditions. The formulated inverse problem was solved. Following the results of calculation the time of start of the filter regeneration process was determined, as well as the period of regeneration process and the amount of regeneration and wash water. Multi-parameter optimization of water treatment process for thermal power plants allowed decreasing the amount of wastewater by 15%.

Keywords: direct problem, multiparametric optimization, optimization parameters, water treatment

Procedia PDF Downloads 389
14916 Advanced Digital Manufacturing: Case Study

Authors: Abdelrahman Abdelazim

Abstract:

Most industries are looking for technologies that are easy to use, efficient and fast to accomplish. To implement these, factories tend to use advanced systems that could alter complicity to simplicity and rudimentary to advancement. Cloud Manufacturing is a new movement that aims to mirror and integrate cloud computing into manufacturing. Amongst cloud manufacturing various advantages are decreasing the human involvements and increasing the dependency on automated machines, which in turns decreases human errors and increases efficiency. A reliable and extraordinary performance processes with minimum errors are highly desired factors of today’s manufacturers. At the glance it seems to be the best alternative, however, the implementation of a cloud system can be very challenging. This work investigates cloud manufacturing in details, it outlines its advantages and disadvantages by converting a local factory in Kuwait to a cloud-ready system. Initially the flow of the factory’s manufacturing process has been analyzed identifying the bottlenecks and illustrating how cloud manufacturing can eliminate them. Following this an automation process has been analyzed and implemented. A comparison between the process before and after the adaptation has been carried out showing the effects on the cost, the output and the efficiency of the process.

Keywords: cloud manufacturing, automation, Kuwait industrial sector, advanced digital manufacturing

Procedia PDF Downloads 774
14915 Cyber Operational Design and Military Decision Making Process

Authors: M. Karaman, H. Catalkaya

Abstract:

Due to the complex nature of cyber attacks and their effects ranging from personal to governmental level, it becomes one of the priority tasks for operation planners to take into account the risks, influences and effects of cyber attacks. However it can also be embedded or integrated technically with electronic warfare planning, cyber operation planning is needed to have a sole and broadened perspective. This perspective embodies itself firstly in operational design and then military decision making process. In order to find out the ill-structured problems, understand or visualize the operational environment and frame the problem, operational design can help support cyber operation planners and commanders. After having a broadened and conceptual startup with cyber operational design, military decision making process will follow the principles of design into more concrete elements like reaching results after risk management and center of gravity analysis of our and the enemy. In this paper we tried to emphasize the importance of cyber operational design, cyber operation planning and its integration to military decision making problem. In this foggy, uncertain and unaccountable cyber security environment, it is inevitable to stay away from cyber attacks. Therefore, a cyber operational design should be formed with line of operations, decisive points and end states in cyber then a tactical military decision making process should be followed with cyber security focus in order to support the whole operation.

Keywords: cyber operational design, military decision making process (MDMP), operation planning, end state

Procedia PDF Downloads 590
14914 Improved Pattern Matching Applied to Surface Mounting Devices Components Localization on Automated Optical Inspection

Authors: Pedro M. A. Vitoriano, Tito. G. Amaral

Abstract:

Automated Optical Inspection (AOI) Systems are commonly used on Printed Circuit Boards (PCB) manufacturing. The use of this technology has been proven as highly efficient for process improvements and quality achievements. The correct extraction of the component for posterior analysis is a critical step of the AOI process. Nowadays, the Pattern Matching Algorithm is commonly used, although this algorithm requires extensive calculations and is time consuming. This paper will present an improved algorithm for the component localization process, with the capability of implementation in a parallel execution system.

Keywords: AOI, automated optical inspection, SMD, surface mounting devices, pattern matching, parallel execution

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14913 Silicon Carbide (SiC) Crystallization Obtained as a Side Effect of SF6 Etching Process

Authors: N. K. A. M. Galvão, A. Godoy Jr., A. L. J. Pereira, G. V. Martins, R. S. Pessoa, H. S. Maciel, M. A. Fraga

Abstract:

Silicon carbide (SiC) is a wide band-gap semiconductor material with very attractive properties, such as high breakdown voltage, chemical inertness, and high thermal and electrical stability, which makes it a promising candidate for several applications, including microelectromechanical systems (MEMS) and electronic devices. In MEMS manufacturing, the etching process is an important step. It has been proved that wet etching of SiC is not feasible due to its high bond strength and high chemical inertness. In view of this difficulty, the plasma etching technique has been applied with paramount success. However, in most of these studies, only the determination of the etching rate and/or morphological characterization of SiC, as well as the analysis of the reactive ions present in the plasma, are lowly explored. There is a lack of results in the literature on the chemical and structural properties of SiC after the etching process [4]. In this work, we investigated the etching process of sputtered amorphous SiC thin films on Si substrates in a reactive ion etching (RIE) system using sulfur hexafluoride (SF6) gas under different RF power. The results of the chemical and structural analyses of the etched films revealed that, for all conditions, a SiC crystallization occurred, in addition to fluoride contamination. In conclusion, we observed that SiC crystallization is a side effect promoted by structural, morphological and chemical changes caused by RIE SF6 etching process.

Keywords: plasma etching, plasma deposition, Silicon Carbide, microelectromechanical systems

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14912 Analysis and Identification of Different Factors Affecting Students’ Performance Using a Correlation-Based Network Approach

Authors: Jeff Chak-Fu Wong, Tony Chun Yin Yip

Abstract:

The transition from secondary school to university seems exciting for many first-year students but can be more challenging than expected. Enabling instructors to know students’ learning habits and styles enhances their understanding of the students’ learning backgrounds, allows teachers to provide better support for their students, and has therefore high potential to improve teaching quality and learning, especially in any mathematics-related courses. The aim of this research is to collect students’ data using online surveys, to analyze students’ factors using learning analytics and educational data mining and to discover the characteristics of the students at risk of falling behind in their studies based on students’ previous academic backgrounds and collected data. In this paper, we use correlation-based distance methods and mutual information for measuring student factor relationships. We then develop a factor network using the Minimum Spanning Tree method and consider further study for analyzing the topological properties of these networks using social network analysis tools. Under the framework of mutual information, two graph-based feature filtering methods, i.e., unsupervised and supervised infinite feature selection algorithms, are used to analyze the results for students’ data to rank and select the appropriate subsets of features and yield effective results in identifying the factors affecting students at risk of failing. This discovered knowledge may help students as well as instructors enhance educational quality by finding out possible under-performers at the beginning of the first semester and applying more special attention to them in order to help in their learning process and improve their learning outcomes.

Keywords: students' academic performance, correlation-based distance method, social network analysis, feature selection, graph-based feature filtering method

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14911 Energy Efficient Retrofitting and Optimization of Dual Mixed Refrigerant Natural Gas Liquefaction Process

Authors: Muhammad Abdul Qyyum, Kinza Qadeer, Moonyong Lee

Abstract:

Globally, liquefied natural gas (LNG) has drawn interest as a green energy source in comparison with other fossil fuels, mainly because of its ease of transport and low carbon dioxide emissions. It is expected that demand for LNG will grow steadily over the next few decades. In addition, because the demand for clean energy is increasing, LNG production facilities are expanding into new natural gas reserves across the globe. However, LNG production is an energy and cost intensive process because of the huge power requirements for compression and refrigeration. Therefore, one of the major challenges in the LNG industry is to improve the energy efficiency of existing LNG processes through economic and ecological strategies. The advancement in expansion devices such as two-phase cryogenic expander (TPE) and cryogenic hydraulic turbine (HT) were exploited for energy and cost benefits in natural gas liquefaction. Retrofitting the conventional Joule–Thompson (JT) valve with TPE and HT have the potential to improve the energy efficiency of LNG processes. This research investigated the potential feasibility of the retrofitting of a dual mixed refrigerant (DMR) process by replacing the isenthalpic expansion with isentropic expansion corresponding to energy efficient LNG production. To fully take the potential benefit of the proposed process retrofitting, the proposed DMR schemes were optimized by using a Coggins optimization approach, which was implemented in Microsoft Visual Studio (MVS) environment and linked to the rigorous HYSYS® model. The results showed that the required energy of the proposed isentropic expansion based DMR process could be saved up to 26.5% in comparison with the conventional isenthalpic based DMR process using the JT valves. Utilization of the recovered energy into boosting the natural gas feed pressure could further improve the energy efficiency of the LNG process up to 34% as compared to the base case. This work will help the process engineers to overcome the challenges relating to energy efficiency and safety concerns of LNG processes. Furthermore, the proposed retrofitting scheme can also be implemented to improve the energy efficiency of other isenthalpic expansion based energy intensive cryogenic processes.

Keywords: cryogenic liquid turbine, Coggins optimization, dual mixed refrigerant, energy efficient LNG process, two-phase expander

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14910 Integrating Process Planning, WMS Dispatching, and WPPW Weighted Due Date Assignment Using a Genetic Algorithm

Authors: Halil Ibrahim Demir, Tarık Cakar, Ibrahim Cil, Muharrem Dugenci, Caner Erden

Abstract:

Conventionally, process planning, scheduling, and due-date assignment functions are performed separately and sequentially. The interdependence of these functions requires integration. Although integrated process planning and scheduling, and scheduling with due date assignment problems are popular research topics, only a few works address the integration of these three functions. This work focuses on the integration of process planning, WMS scheduling, and WPPW due date assignment. Another novelty of this work is the use of a weighted due date assignment. In the literature, due dates are generally assigned without considering the importance of customers. However, in this study, more important customers get closer due dates. Typically, only tardiness is punished, but the JIT philosophy punishes both earliness and tardiness. In this study, all weighted earliness, tardiness, and due date related costs are penalized. As no customer desires distant due dates, such distant due dates should be penalized. In this study, various levels of integration of these three functions are tested and genetic search and random search are compared both with each other and with ordinary solutions. Higher integration levels are superior, while search is always useful. Genetic searches outperformed random searches.

Keywords: process planning, weighted scheduling, weighted due-date assignment, genetic algorithm, random search

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14909 The Role Of Data Gathering In NGOs

Authors: Hussaini Garba Mohammed

Abstract:

Background/Significance: The lack of data gathering is affecting NGOs world-wide in general to have good data information about educational and health related issues among communities in any country and around the world. For example, HIV/AIDS smoking (Tuberculosis diseases) and COVID-19 virus carriers is becoming a serious public health problem, especially among old men and women. But there is no full details data survey assessment from communities, villages, and rural area in some countries to show the percentage of victims and patients, especial with this world COVID-19 virus among the people. These data are essential to inform programming targets, strategies, and priorities in getting good information about data gathering in any society.

Keywords: reliable information, data assessment, data mining, data communication

Procedia PDF Downloads 182
14908 Design of Multi-Loop Controller for Minimization of Energy Consumption in the Distillation Column

Authors: Vinayambika S. Bhat, S. Shanmuga Priya, I. Thirunavukkarasu, Shreeranga Bhat

Abstract:

An attempt has been made to design a decoupling controller for systems with more inputs more outputs with dead time in it. The de-coupler is designed for the chemical process industry 3×3 plant transfer function with dead time. The Quantitative Feedback Theory (QFT) based controller has also been designed here for the 2×2 distillation column transfer function. The developed control techniques were simulated using the MATLAB/Simulink. Also, the stability of the process was analyzed, together with the presence of various perturbations in it. Time domain specifications like setting time along with overshoot and oscillations were analyzed to prove the efficiency of the de-coupler method. The load disturbance rejection was tested along with its performance. The QFT control technique was synthesized based on the stability and performance specifications in the presence of uncertainty in time constant of the plant transfer function through sequential loop shaping technique. Further, the energy efficiency of the distillation column was improved by proper tuning of the controller. A distillation column consumes 3% of the total energy consumption of the world. A suitable control technique is very important from an economic point of view. The real time implementation of the process is under process in our laboratory.

Keywords: distillation, energy, MIMO process, time delay, robust stability

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14907 Study of Machinability for Titanium Alloy Ti-6Al-4V through Chip Formation in Milling Process

Authors: Moaz H. Ali, Ahmed H. Al-Saadi

Abstract:

Most of the materials used in the industry of aero-engine components generally consist of titanium alloys. Advanced materials, because of their excellent combination of high specific strength, lightweight, and general corrosion resistance. In fact, chemical wear resistance of aero-engine alloy provide a serious challenge for cutting tool material during the machining process. The reduction in cutting temperature distributions leads to an increase in tool life and a decrease in wear rate. Hence, the chip morphology and segmentation play a predominant role in determining machinability and tool wear during the machining process. The result of low thermal conductivity and diffusivity of this alloy in the concentration of high temperatures at the tool-work-piece and tool-chip interface. Consequently, the chip morphology is very important in the study of machinability of metals as well as the study of cutting tool wear. Otherwise, the result will be accelerating tool wear, increasing manufacturing cost and time consuming.

Keywords: machinability, titanium alloy (ti-6al-4v), chip formation, milling process

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14906 Statistical Quality Control on Assignable Causes of Variation on Cement Production in Ashaka Cement PLC Gombe State

Authors: Hamisu Idi

Abstract:

The present study focuses on studying the impact of influencer recommendation in the quality of cement production. Exploratory research was done on monthly basis, where data were obtained from secondary source i.e. the record kept by an automated recompilation machine. The machine keeps all the records of the mills downtime which the process manager checks for validation and refer the fault (if any) to the department responsible for maintenance or measurement taking so as to prevent future occurrence. The findings indicated that the product of the Ashaka Cement Plc. were considered as qualitative, since all the production processes were found to be in control (preset specifications) with the exception of the natural cause of variation which is normal in the production process as it will not affect the outcome of the product. It is reduced to the bearest minimum since it cannot be totally eliminated. It is also hopeful that the findings of this study would be of great assistance to the management of Ashaka cement factory and the process manager in particular at various levels in the monitoring and implementation of statistical process control. This study is therefore of great contribution to the knowledge in this regard and it is hopeful that it would open more research in that direction.

Keywords: cement, quality, variation, assignable cause, common cause

Procedia PDF Downloads 267
14905 Characterization of Waste Thermocol Modified Bitumen by Spectroscopy, Microscopic Technique, and Dynamic Shear Rheometer

Authors: Supriya Mahida, Sangita, Yogesh U. Shah, Shanta Kumar

Abstract:

The global production of thermocol increasing day by day, due to vast applications of the use of thermocole in many sectors. Thermocol being non-biodegradable and more toxic than plastic leads towards a number of problems like its management into value-added products, environmental damage and landfill problems due to weight to volume ratio. Utilization of waste thermocol for modification of bitumen binders resulted in waste thermocol modified bitumen (WTMB) used in road construction and maintenance technology. Modification of bituminous mixes through incorporating thermocol into bituminous mixes through a dry process is one of the new options besides recycling process which consumes lots of waste thermocol. This process leads towards waste management and remedies against thermocol waste disposal. The present challenge is to dispose the thermocol waste under different forms in road infrastructure, either through the dry process or wet process to be developed in future. This paper focuses on the use of thermocol wastes which is mixed with VG 10 bitumen in proportions of 0.5%, 1%, 1.5%, and 2% by weight of bitumen. The physical properties of neat bitumen are evaluated and compared with modified VG 10 bitumen having thermocol. Empirical characterization like penetration, softening, and viscosity of bitumen has been carried out. Thermocol and waste thermocol modified bitumen (WTMB) were further analyzed by Fourier Transform Infrared Spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), and Dynamic Shear Rheometer (DSR).

Keywords: DSR, FESEM, FT-IR, thermocol wastes

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14904 Understanding the Conflict Between Ecological Environment and Human Activities in the Process of Urbanization

Authors: Yazhou Zhou, Yong Huang, Guoqin Ge

Abstract:

In the process of human social development, the coupling and coordinated development among the ecological environment(E), production(P), and living functions(L) is of great significance for sustainable development. This study uses an improved coupling coordination degree model (CCDM) to discover the coordination conflict between E and human settlement environment. The main work of this study is as follows: (1) It is found that in the process of urbanization development of Ya 'an city from 2014 to 2018, the degree of coupling (DOC) value between E, P, and L is high, but the coupling coordination degree (CCD) of the three is low, especially the DOC value of E and the other two has the biggest decline. (2) A more objective weight value is obtained, which can avoid the analysis error caused by subjective judgment weight value.

Keywords: ecological environment, coupling coordination degree, neural network, sustainable development

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14903 Torrefaction of Biomass Pellets: Modeling of the Process in a Fixed Bed Reactor

Authors: Ekaterina Artiukhina, Panagiotis Grammelis

Abstract:

Torrefaction of biomass pellets is considered as a useful pretreatment technology in order to convert them into a high quality solid biofuel that is more suitable for pyrolysis, gasification, combustion and co-firing applications. In the course of torrefaction the temperature varies across the pellet, and therefore chemical reactions proceed unevenly within the pellet. However, the uniformity of the thermal distribution along the pellet is generally assumed. The torrefaction process of a single cylindrical pellet is modeled here, accounting for heat transfer coupled with chemical kinetics. The drying sub-model was also introduced. The non-stationary process of wood pellet decomposition is described by the system of non-linear partial differential equations over the temperature and mass. The model captures well the main features of the experimental data.

Keywords: torrefaction, biomass pellets, model, heat, mass transfer

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14902 Breakthrough Innovation Thinking Technology of a Conglomerate for Next Generation Plan

Authors: Dongkyu Lee, Doan-Quoc Hoan, Soomi Shin

Abstract:

The purpose of this study is to suggest the Value Innovation type Breakthrough Innovation which is a Big Thinking Process that realizes a creative idea for the next generation innovation Master Plan of a company. The BI based on the PVI methodology is believed to contribute to the launching of a new business, the acquisition of new markets, and the development of an innovative management process.

Keywords: value, innovation, breakthrough innovation, Korean firm

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14901 Multi-Point Dieless Forming Product Defect Reduction Using Reliability-Based Robust Process Optimization

Authors: Misganaw Abebe Baye, Ji-Woo Park, Beom-Soo Kang

Abstract:

The product quality of multi-point dieless forming (MDF) is identified to be dependent on the process parameters. Moreover, a certain variation of friction and material properties may have a substantially worse influence on the final product quality. This study proposed on how to compensate the MDF product defects by minimizing the sensitivity of noise parameter variations. This can be attained by reliability-based robust optimization (RRO) technique to obtain the optimal process setting of the controllable parameters. Initially two MDF Finite Element (FE) simulations of AA3003-H14 saddle shape showed a substantial amount of dimpling, wrinkling, and shape error. FE analyses are consequently applied on ABAQUS commercial software to obtain the correlation between the control process setting and noise variation with regard to the product defects. The best prediction models are chosen from the family of metamodels to swap the computational expensive FE simulation. Genetic algorithm (GA) is applied to determine the optimal process settings of the control parameters. Monte Carlo Analysis (MCA) is executed to determine how the noise parameter variation affects the final product quality. Finally, the RRO FE simulation and the experimental result show that the amendment of the control parameters in the final forming process leads to a considerably better-quality product.

Keywords: dimpling, multi-point dieless forming, reliability-based robust optimization, shape error, variation, wrinkling

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14900 Envisioning Process in Medium Enterprises: An Exploratory Study of Cambodian Living Arts

Authors: Alexandre Bédard, Caroline Coulombe, Jonathan Harvey

Abstract:

Envisioning process (EP) in medium enterprises is treated equally in very small enterprises. Building on the concept of social construction, this study aims to explore how envisioning is constructed in a medium enterprise in which stakeholders are involved and how it is influenced. We use a unique case method based on qualitative data collected through 11 interviews representing various members of the organization. Through the discussion of the findings, we were able to confirm the social construction of the EP and to identify three main stakeholders responsible for the construction of the vision, mainly political and social powers, actors of the organization, and financial providers. Moreover, EP is influenced by external factors; in this case, the history of the organization and the value and importance of the art and the culture for Cambodians.

Keywords: envisioning process, social constructivism, medium enterprise, legitimacy

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14899 Design of Uniform Spray Nozzle and Simulation of Carrier Gas Flow Rate Distribution for FTO Thin Film Fabrication Process

Authors: HyeSuk Ri, HyonChol Kim, NamChol Yu

Abstract:

The FTO thin films were deposited on 15 cm × 15 cm glass substrates by ultrasonic spray pyrolysis, and the influence of process parameters on the film properties was investigated. This paper is the first report on the design of a uniform nozzle and simulating the carrier gas flow characteristics in an ultrasonic spray pyrolysis process. The uniformity of FTO films was evaluated by surface resistivity. The structure, surface morphology and optical properties of FTO films were investigated using scanning electron microscopy, X-ray diffraction, and UV-Vis spectroscopy. The process conditions for film preparation were SnCl₄ concentration of 1.34 mol, NH₄F concentration of 0.08 mol, temperature of 500 °C, deposition time of 15 min, carrier gas flow rate of 3 m/s, distance between nozzle and substrate of 0.7 cm. The transmittance of the fabricated FTO films was 80%, the surface resistance showed a uniform behavior at 14-15Ω/cm² and the X-ray analysis showed a high orientation of SnO₂ crystals in the 200-plane. SEM analysis showed that the crystallite size was constant.

Keywords: nozzle design, FTO film, simulation, ultrasonic spray pyrolysis

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14898 Effect of the Initial Billet Shape Parameters on the Final Product in a Backward Extrusion Process for Pressure Vessels

Authors: Archana Thangavelu, Han-Ik Park, Young-Chul Park, Joon-Hong Park

Abstract:

In this numerical study, we have proposed a method for evaluation of backward extrusion process of pressure vessel made up of steel. Demand for lighter and stiffer products have been increasing in the last years especially in automobile engineering. Through detailed finite element analysis, effective stress, strain and velocity profile have been obtained with optimal range. The process design of a forward and backward extrusion axe-symmetric part has been studied. Forging is mainly carried out because forged products are highly reliable and possess superior mechanical properties when compared to normal products. Performing computational simulations of 3D hot forging with various dimensions of billet and optimization of weight is carried out using Taguchi Orthogonal Array (OA) Optimization technique. The technique used in this study can be used for newly developed materials to investigate its forgeability for much complicated shapes in closed hot die forging process.

Keywords: backward extrusion, hot forging, optimization, finite element analysis, Taguchi method

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14897 Internationalization Process Model for Construction Firms: Stages and Strategies

Authors: S. Ping Ho, R. Dahal

Abstract:

The global economy has drastically changed how firms operate and compete. Although the construction industry is ‘local’ by its nature, the internationalization of the construction industry has become an inevitable reality. As a result of global competition, staying domestic is no longer safe from competition and, on the contrary, to grow and become an MNE (multi-national enterprise) becomes one of the important strategies for a firm to survive in the global competition. For the successful entrance into competing markets, the firms need to re-define their competitive advantages and re-identify the sources of the competitive advantages. A firm’s initiation of internationalization is not necessarily a result of strategic planning but also involves certain idiosyncratic events that pave the path leading to a firm’s internationalization. For example, a local firm’s incidental or unintentional collaboration with an MNE can become the initiating point of its internationalization process. However, because of the intensive competition in today’s global movement, many firms were compelled to initiate their internationalization as a strategic response to the competition. Understandingly stepping in in the process of internationalization and appropriately implementing the strategies (in the process) at different stages lead the construction firms to a successful internationalization journey. This study is carried out to develop a model of the internationalization process, which derives appropriate strategies that the construction firms can implement at each stage. The proposed model integrates two major and complementary views of internationalization and expresses the dynamic process of internationalization in three stages, which are the pre-international (PRE) stage, the foreign direct investment (FDI) stage, and the multi-national enterprise (MNE) stage. The strategies implied in the proposed model are derived, focusing on capability building, market locations, and entry modes based on the resource-based views: value, rareness, imitability, and substitutability (VRIN). With the proposed dynamic process model the potential construction firms which are willing to expand their business market area can be benefitted. Strategies for internationalization, such as core competence strategy, market selection, partner selection, and entry mode strategy, can be derived from the proposed model. The internationalization process is expressed in two different forms. First, we discuss the construction internationalization process, identify the driving factor/s of the process, and explain the strategy formation in the process. Second, we define the stages of internationalization along the process and the corresponding strategies in each stage. The strategies may include how to exploit existing advantages for the competition at the current stage and develop or explore additional advantages appropriate for the next stage. Particularly, the additionally developed advantages will then be accumulated and drive forward the firm’s stage of internationalization, which will further determine the subsequent strategies, and so on and so forth, spiraling up the stages of a higher degree of internationalization. However, the formation of additional strategies for the next stage does not happen automatically, and the strategy evolution is based on the firm’s dynamic capabilities.

Keywords: construction industry, dynamic capabilities, internationalization process, internationalization strategies, strategic management

Procedia PDF Downloads 65
14896 Towards a Business Process Model Deriving from an Intentional Perspective

Authors: Omnia Saidani Neffati, Rim Samia Kaabi, Naoufel Kraiem

Abstract:

In this paper, we propose an approach aiming at (i) representing services at two levels: the intentional level and the organizational level, and (ii) establishing mechanisms allowing to make a transition from the first level to the second one in order to execute intentional services. An example is used to validate our approach.

Keywords: intentional service, business process, BPMN, MDE, intentional service execution

Procedia PDF Downloads 397
14895 Principles of Municipal Sewage Sludge Bioconversion into Biomineral Fertilizer

Authors: K. V. Kalinichenko, G. N. Nikovskaya

Abstract:

The efficiency of heavy metals removal from sewage sludge in bioleaching with heterotrophic, chemoautotrophic (sulphur-oxidizing) sludge cenoses and chemical leaching (in distilled water, weakly acidic or alkaline medium) was compared. The efficacy of heavy metals removal from sewage sludge varied from 83 % (Zn) up to 14 % (Cr) and followed the order: Zn > Mn > Cu > Ni > Co > Pb > Cr. The advantages of metals bioleaching process at heterotrophic metabolism was shown. A new process for bioconversation of sewage sludge into fertilizer at middle temperature after partial heavy metals removal was developed. This process is based on enhancing vital ability of heterotrophic microorganisms by adding easily metabolized nutrients and synthesis of metabolites by growing sludge cenoses. These metabolites possess the properties of heavy metals extractants and flocculants which provide sludge flocks sedimentation and concentration. The process results in biomineral fertilizer with immobilized sludge bioelements with prolonged action. The fertilizer obtained satisfied the EU limits for the sewage sludge of agricultural utilization. High efficiency of the biomineral fertilizers obtained has been demonstrated in vegetation experiments.

Keywords: fertilizer, heavy metals, leaching, sewage sludge

Procedia PDF Downloads 392
14894 Applying Concurrent Development Process for the Web Using Aspect-Oriented Approach

Authors: Hiroaki Fukuda

Abstract:

This paper shows a concurrent development process for modern web application, called Rich Internet Application (RIA), and describes its effect using a non-trivial application development. In the last years, RIAs such as Ajax and Flex have become popular based mainly on high-speed network. RIA provides sophisticated interfaces and user experiences, therefore, the development of RIA requires two kinds of engineer: a developer who implements business logic, and a designer who designs interface and experiences. Although collaborative works are becoming important for the development of RIAs, shared resources such as source code make it difficult. For example, if a design of interface is modified after developers have finished business logic implementations, they need to repeat the same implementations, and also tests to verify application’s behavior. MVC architecture and Object-oriented programming (OOP) enables to dividing an application into modules such as interfaces and logic, however, developers and/or designers have to write pieces of code (e.g., event handlers) that make these modules work as an application. On the other hand, Aspect-oriented programming (AOP) is ex- pected to solve complexity of application software development nowadays. AOP provides methods to separate crosscutting concerns that are scattered pieces of code from primary concerns. In this paper, we provide a concurrent development process for RIAs by introducing AOP concept. This process makes it possible to reduce shared resources between developers and designers, therefore they can perform their tasks concurrently. In addition, we describe experiences of development for a practical application using our proposed development process to show its availability.

Keywords: aspect-oriented programming, concurrent, development process, rich internet application

Procedia PDF Downloads 303
14893 The Moment of the Optimal Average Length of the Multivariate Exponentially Weighted Moving Average Control Chart for Equally Correlated Variables

Authors: Edokpa Idemudia Waziri, Salisu S. Umar

Abstract:

The Hotellng’s T^2 is a well-known statistic for detecting a shift in the mean vector of a multivariate normal distribution. Control charts based on T have been widely used in statistical process control for monitoring a multivariate process. Although it is a powerful tool, the T statistic is deficient when the shift to be detected in the mean vector of a multivariate process is small and consistent. The Multivariate Exponentially Weighted Moving Average (MEWMA) control chart is one of the control statistics used to overcome the drawback of the Hotellng’s T statistic. In this paper, the probability distribution of the Average Run Length (ARL) of the MEWMA control chart when the quality characteristics exhibit substantial cross correlation and when the process is in-control and out-of-control was derived using the Markov Chain algorithm. The derivation of the probability functions and the moments of the run length distribution were also obtained and they were consistent with some existing results for the in-control and out-of-control situation. By simulation process, the procedure identified a class of ARL for the MEWMA control when the process is in-control and out-of-control. From our study, it was observed that the MEWMA scheme is quite adequate for detecting a small shift and a good way to improve the quality of goods and services in a multivariate situation. It was also observed that as the in-control average run length ARL0¬ or the number of variables (p) increases, the optimum value of the ARL0pt increases asymptotically and as the magnitude of the shift σ increases, the optimal ARLopt decreases. Finally, we use the example from the literature to illustrate our method and demonstrate its efficiency.

Keywords: average run length, markov chain, multivariate exponentially weighted moving average, optimal smoothing parameter

Procedia PDF Downloads 425
14892 Spatial Rank-Based High-Dimensional Monitoring through Random Projection

Authors: Chen Zhang, Nan Chen

Abstract:

High-dimensional process monitoring becomes increasingly important in many application domains, where usually the process distribution is unknown and much more complicated than the normal distribution, and the between-stream correlation can not be neglected. However, since the process dimension is generally much bigger than the reference sample size, most traditional nonparametric multivariate control charts fail in high-dimensional cases due to the curse of dimensionality. Furthermore, when the process goes out of control, the influenced variables are quite sparse compared with the whole dimension, which increases the detection difficulty. Targeting at these issues, this paper proposes a new nonparametric monitoring scheme for high-dimensional processes. This scheme first projects the high-dimensional process into several subprocesses using random projections for dimension reduction. Then, for every subprocess with the dimension much smaller than the reference sample size, a local nonparametric control chart is constructed based on the spatial rank test to detect changes in this subprocess. Finally, the results of all the local charts are fused together for decision. Furthermore, after an out-of-control (OC) alarm is triggered, a diagnostic framework is proposed. using the square-root LASSO. Numerical studies demonstrate that the chart has satisfactory detection power for sparse OC changes and robust performance for non-normally distributed data, The diagnostic framework is also effective to identify truly changed variables. Finally, a real-data example is presented to demonstrate the application of the proposed method.

Keywords: random projection, high-dimensional process control, spatial rank, sequential change detection

Procedia PDF Downloads 301