Search results for: outer product expansion

Authors: Wen-Lung Huang, Shih-Pin Chen

Abstract:

This paper investigates the optimization problem of multi-product aggregate production planning (APP) with fuzzy data. From a comprehensive viewpoint of conserving the fuzziness of input information, this paper proposes a method that can completely describe the membership function of the performance measure. The idea is based on the well-known Zadeh-s extension principle which plays an important role in fuzzy theory. In the proposed solution procedure, a pair of mathematical programs parameterized by possibility level a is formulated to calculate the bounds of the optimal performance measure at a . Then the membership function of the optimal performance measure is constructed by enumerating different values of a . Solutions obtained from the proposed method contain more information, and can offer more chance to achieve the feasible disaggregate plan. This is helpful to the decision-maker in practical applications.

Keywords: fuzzy data, aggregate production planning, membership function, parametric programming

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1722

Authors: Dhruvit S. Berawala, Jann R. Ursin, Obrad Slijepcevic

Abstract:

Shale gas is one of the most rapidly growing forms of natural gas. Unconventional natural gas deposits are difficult to characterize overall, but in general are often lower in resource concentration and dispersed over large areas. Moreover, gas is densely packed into the matrix through adsorption which accounts for large volume of gas reserves. Gas production from tight shale deposits are made possible by extensive and deep well fracturing which contacts large fractions of the formation. The conventional reservoir modelling and production forecasting methods, which rely on fluid-flow processes dominated by viscous forces, have proved to be very pessimistic and inaccurate. This paper presents a new approach to forecast shale gas production by detailed modeling of gas desorption, diffusion and non-linear flow mechanisms in combination with statistical representation of these processes. The representation of the model involves a cube as a porous media where free gas is present and a sphere (SiC: Sphere in Cube model) inside it where gas is adsorbed on to the kerogen or organic matter. Further, the sphere is considered consisting of many layers of adsorbed gas in an onion-like structure. With pressure decline, the gas desorbs first from the outer most layer of sphere causing decrease in its molecular concentration. The new available surface area and change in concentration triggers the diffusion of gas from kerogen. The process continues until all the gas present internally diffuses out of the kerogen, gets adsorbs onto available surface area and then desorbs into the nanopores and micro-fractures in the cube. Each SiC idealizes a gas pathway and is characterized by sphere diameter and length of the cube. The diameter allows to model gas storage, diffusion and desorption; the cube length takes into account the pathway for flow in nanopores and micro-fractures. Many of these representative but general cells of the reservoir are put together and linked to a well or hydraulic fracture. The paper quantitatively describes these processes as well as clarifies the geological conditions under which a successful shale gas production could be expected. A numerical model has been derived which is then compiled on FORTRAN to develop a simulator for the production of shale gas by considering the spheres as a source term in each of the grid blocks. By applying SiC to field data, we demonstrate that the model provides an effective way to quickly access gas production rates from shale formations. We also examine the effect of model input properties on gas production.

Keywords: Sphere in Cube Grid Approach to Modelling of Shale Gas Production Using Non-Linear Flow Mechanisms

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 797

Authors: K. X. Cheng, A. L. Goh, K. T. Ooi

Abstract:

The effectiveness of microchannels in enhancing heat transfer has been demonstrated in the semiconductor industry. In order to tap the microscale heat transfer effects into macro geometries, overcoming the cost and technological constraints, microscale passages were created in macro geometries machined using conventional fabrication methods. A cylindrical insert was placed within a pipe, and geometrical profiles were created on the outer surface of the insert to enhance heat transfer under steady-state single-phase liquid flow conditions. However, while heat transfer coefficient values of above 10 kW/m2·K were achieved, the heat transfer enhancement was accompanied by undesirable pressure drop increment. Therefore, this study aims to address the high pressure drop issue using Constructal theory, a universal design law for both animate and inanimate systems. Two designs based on Constructal theory were developed to study the effectiveness of Constructal features in reducing the pressure drop increment as compared to parallel channels, which are commonly found in microchannel fabrication. The hydrodynamic and heat transfer performance for the Tree insert and Constructal fin (Cfin) insert were studied using experimental methods, and the underlying mechanisms were substantiated by numerical results. In technical terms, the objective is to achieve at least comparable increment in both heat transfer coefficient and pressure drop, if not higher increment in the former parameter. Results show that the Tree insert improved the heat transfer performance by more than 16 percent at low flow rates, as compared to the Tree-parallel insert. However, the heat transfer enhancement reduced to less than 5 percent at high Reynolds numbers. On the other hand, the pressure drop increment stayed almost constant at 20 percent. This suggests that the Tree insert has better heat transfer performance in the low Reynolds number region. More importantly, the Cfin insert displayed improved heat transfer performance along with favourable hydrodynamic performance, as compared to Cfinparallel insert, at all flow rates in this study. At 2 L/min, the enhancement of heat transfer was more than 30 percent, with 20 percent pressure drop increment, as compared to Cfin-parallel insert. Furthermore, comparable increment in both heat transfer coefficient and pressure drop was observed at 8 L/min. In other words, the Cfin insert successfully achieved the objective of this study. Analysis of the results suggests that bifurcation of flows is effective in reducing the increment in pressure drop relative to heat transfer enhancement. Optimising the geometries of the Constructal fins is therefore the potential future study in achieving a bigger stride in energy efficiency at much lower costs.

Keywords: Constructal theory, enhanced heat transfer, microchannel, pressure drop.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1464

Authors: O. Benaziz, A. Dorbane, S. Djeraba

Abstract:

The objective of this work is to formulate a dry dispersible form of furosemide in the context of pediatric dose adjustment. To achieve this, we have produced a set of formulas that will be tested in process and after compression. The formula with the best results will be improved to optimize the final shape of the product. Furosemide is the most widely used pediatric diuretic because of its low toxicity. The manufacturing process was chosen taking into account all the data relating to the active ingredient and the excipients used and complying with the specifications and requirements of dispersible tablets. The process used to prepare these tablets was wet granulation. Different excipients were used: lactose, maize starch, magnesium stearate and two superdisintegrants. The mode of incorporation of super-disintegrant changes with each formula. The use of super-disintegrant in the formula allowed optimization of the disintegration time. Prepared tablets were evaluated for weight, content uniformity, hardness, disintegration time, friability and in vitro dissolution test. 

Keywords: Formulation, dispersible tablets, wet granulation, superdisintegrants, disintegration.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1138

Authors: L. Tirabeni, K. E. Soderquist, P. Pisano

Abstract:

Our purpose is to investigate how the relationship between employees and innovation management processes can drive organizations to successful innovations. This research is deeply related to a new way of thinking about human resources management practices. It’s not simply about improving the employees’ engagement, but rather about a different and more radical commitment: the employee can take on the role traditionally played by the customer, namely to become the first tester of an innovative product or service, the first user/customer and eventually the first investor in the innovation. This new perception of employees could create the basis of a novelty in the innovation process where innovation is taken to a next level when the problems with customer driven innovation on the one hand, and employees driven innovation on the other can be balanced. This research identifies an effective approach to innovation where the employees will participate throughout the whole innovation process, not only in the idea creation but also in the idea definition and development by giving feedback in parallel to that provided by customers and lead-users.

Keywords: Employee-Driven Innovation, engagement, human resource management, innovative companies.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1967

Authors: M.Davami, M.Zadshakoyan

Abstract:

Production of hard-to-cut materials with uncoated carbide cutting tools in turning, not only cause tool life reduction but also, impairs the product surface roughness. In this paper, influence of hot machining method were studied and presented in two cases. Case1-Workpiece surface roughness quality with constant cutting parameter and 300 ºC initial workpiece surface temperature. Case 2- Tool temperature variation when cutting with two speeds 78.5 (m/min) and 51 (m/min). The workpiece material and tool used in this study were AISI 1060 steel (45HRC) and uncoated carbide TNNM 120408-SP10(SANDVIK Coromant) respectively. A gas flam heating source was used to preheating of the workpiece surface up to 300 ºC, causing reduction of yield stress about 15%. Results obtained experimentally, show that the method used can considerably improved surface quality of the workpiece.

Keywords: Hard-to-cut material, Hot machining, Surfaceroughness, Tool Temperature

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2174

Authors: Abayomi H. T., Oresanya T. O., Opeifa A. O., Rasheed T. R.

Abstract:

The study was conducted to evaluate the quality characteristics of cookies produced from sweet potato-fermented soybean flour. Cookies were subjected to proximate and sensory analysis to determine the acceptability of the product. Protein, fat and ash increased as the proportion of soybean flour increased, ranging from 13.8-21.7, 1.22-5.25 and 2.20-2.57 respectively. The crude fibre content was within the range of 3.08-4.83%. The moisture content of the cookies decreased with increase in soybean flour from 3.42- 2.13%. Cookies produced from whole sweet potato flour had the highest moisture content of 3.42% while 30% substitution had the lowest moisture content 2.13%. A nine point hedonic scale was used to evaluate the organoleptic characteristics of the cookies. The sensory analysis indicated that there was no significant difference between the cookies produced even when compared to the control 100% sweet potato cookies. The overall acceptance of the cookies was ranked to 20% soybean flour substitute.

Keywords: Cookies, Fermented Soybean, Overall Acceptability, Sweet Potatoes.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5456

Authors: Iman Atighi, Jalal Soleimannejad, Reza Pourjafarabadi, Saeid Moradpour

Abstract:

In the past, we could increase profit by increasing product prices. But in the new decade, a competitive market does not let us to increase profit with increased prices. Therefore, the only way to increase profit will be to reduce costs. A significant percentage of production costs are the maintenance costs, and analysis of these costs could achieve more profit. Most maintenance strategies such as RCM (Reliability-Center-Maintenance), TPM (Total Productivity Maintenance), PM (Preventive Maintenance) and etc., are trying to reduce maintenance costs. In this paper, decreasing the maintenance costs of Concentration Plant of Golgohar Iron Ore Mining & Industrial Company (GeG) was examined by using of MTBF (Mean Time Between Failures) and MTTR (Mean Time To Repair) analyses. These analyses showed that instead of buying new machines and increasing costs in order to promote capacity, the improving of MTBF and MTTR indexes would solve capacity problems in the best way and decrease costs.

Keywords: GeG Company, maintainability, maintenance costs, reliability-center-maintenance.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 691

Authors: Halûk Gümüşkaya

Abstract:

In this paper we analyze the core issues affecting software architecture in enterprise projects where a large number of people at different backgrounds are involved and complex business, management and technical problems exist. We first give general features of typical enterprise projects and then present foundations of software architectures. The detailed analysis of core issues affecting software architecture in software development phases is given. We focus on three main areas in each development phase: people, process, and management related issues, structural (product) issues, and technology related issues. After we point out core issues and problems in these main areas, we give recommendations for designing good architecture. We observed these core issues and the importance of following the best software development practices and also developed some novel practices in many big enterprise commercial and military projects in about 10 years of experience.

Keywords: Software architecture, enterprise projects.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3581

Authors: Ankit Mitra

Abstract:

An adder is one of the most integral component of a digital system like a digital signal processor or a microprocessor. Being an extremely computationally intensive part of a system, the optimization for speed and power consumption of the adder is of prime importance. In this paper we have designed a 1 bit full adder cell based on dynamic TSPC logic to achieve high speed operation. A high threshold voltage sleep transistor is used to reduce the static power dissipation in standby mode. The circuit is designed and simulated in TSPICE using TSMC 180nm CMOS process. Average power consumption, delay and power-delay product is measured which showed considerable improvement in performance over the existing full adder designs.

Keywords: CMOS, TSPC, MTCMOS, ALU, Clock gating, power gating, pipelining.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3051

Authors: N. Manavizadeh , M. Rabbani , H. Sotudian , F. Jolai

Abstract:

Mixed Model Production is the practice of assembling several distinct and different models of a product on the same assembly line without changeovers and then sequencing those models in a way that smoothes the demand for upstream components. In this paper, we consider an objective function which minimizes total stoppage time and total idle time and it is presented sequence dependent set up time. Many studies have been done on the mixed model assembly lines. But in this paper we specifically focused on reducing the idle times. This is possible through various help policies. For improving the solutions, some cases developed and about 40 tests problem was considered. We use scatter search for optimization and for showing the efficiency of our algorithm, experimental results shows behavior of method. Scatter search and help policies can produce high quality answers, so it has been used in this paper.

Keywords: mixed model assembly lines, Scatter search, help policies, idle time, Stoppage time

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1473

Authors: Deepak Kumar, Vivek Kumar, V. P. Singh

Abstract:

This paper describes a steady state model of a multiple effect evaporator system for simulation and control purposes. The model includes overall as well as component mass balance equations, energy balance equations and heat transfer rate equations for area calculations for all the effects. Each effect in the process is represented by a number of variables which are related by the energy and material balance equations for the feed, product and vapor flow for backward, mixed and split feed. For simulation 'fsolve' solver in MATLAB source code is used. The optimality of three sequences i.e. backward, mixed and splitting feed is studied by varying the various input parameters.

Keywords: MATLAB "fsolve" solver, multiple effectevaporators, black liquor, feeding sequences.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3232

Authors: C. Senanayake, S. Veera Ragavan

Abstract:

Warehousing is commonly used in factories for the storage of products until delivery of orders. As the amount of products stored increases it becomes tedious to be carried out manually. In recent years, the manual storing has converted into fully or partially computer controlled systems, also known as Automated Storage and Retrieval Systems (AS/RS). This paper discusses an ASRS system, which was designed such that the best storage location for the products is determined by utilizing a fuzzy control system. The design maintains the records of the products to be/already in store and the storage/retrieval times along with the availability status of the storage locations. This paper discusses on the maintenance of the above mentioned records and the utilization of the concept of fuzzy logic in order to determine the optimum storage location for the products. The paper will further discuss on the dynamic splitting and merging of the storage locations depending on the product sizes.

Keywords: ASRS, fuzzy control systems, MySQL database, dynamic splitting and merging.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2121

Authors: R. Dyondi, S. K. Jha

Abstract:

The purpose of the paper is to address the strategic risk issues surrounding Hindi film distribution in Mumbai for a film distributor, who acts as an entrepreneur when launching a product (movie) in the market (film territory).The paper undertakes a fundamental review of films and risk in the Hindi film industry and applies Grounded Theory technique to understand the complex phenomena of risk taking behavior of the film distributors (both independent and studios) in Mumbai. Rich in-depth interviews with distributors are coded to develop core categories through constant comparison leading to conceptualization of the phenomena of interest. This paper is a first-of-its-kind-attempt to understand risk behavior of a distributor, which is akin to entrepreneurial risk behavior under conditions of uncertainty.

Keywords: Entrepreneurial Risk Behavior, Film Distribution Strategy, Hindi Film Industry, Risk.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2591

Authors: Sonia Regina Lyra

Abstract:

The desire for unequivocal clarity is understandable, but this can make one forget that things of the soul are experiential processes, or transformations, which should never be designated unilaterally if it is not wanted to transform something that moves, a living thing, into something static. Among the so-called ‘things of the soul’ there are especially spontaneous fantasies, that emerge during the processes, as a result from the use of the active imagination technique, for when fantasy is not forced, violated, or subjugated by an illegitimate, intellectually preconceived idea, then it is a legitimate and authentic product of the unconscious mind. This is how one can gain access to unadulterated information about everything that transcends the conscious mind. However, it is vital to discern between ego and non-ego, because this principle will result in a release of energy and a renewal of life, which will come to have meaning. This study will deal with the active imagination as a knowledge that depends on the individual experience of the therapist because the patient will be taken just to reach where the unconscious of the therapist was assimilated to his own conscience. In this way, the therapist becomes the method itself, being his personality, a fundamental part of an effective factor.

Keywords: Active imagination, effective factor, symptom, transformation.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 623

Authors: Mihai Caramihai, Irina Severin, Ana Aurelia Chirvase, Adrian Onu, Cristina Tanase, Camelia Ungureanu

Abstract:

An immunomodulator bioproduct is prepared in a batch bioprocess with a modified bacterium Pseudomonas aeruginosa. The bioprocess is performed in 100 L Bioengineering bioreactor with 42 L cultivation medium made of peptone, meat extract and sodium chloride. The optimal bioprocess parameters were determined: temperature – 37 0C, agitation speed - 300 rpm, aeration rate – 40 L/min, pressure – 0.5 bar, Dow Corning Antifoam M-max. 4 % of the medium volume, duration - 6 hours. This kind of bioprocesses are appreciated as difficult to control because their dynamic behavior is highly nonlinear and time varying. The aim of the paper is to present (by comparison) different models based on experimental data. The analysis criteria were modeling error and convergence rate. The estimated values and the modeling analysis were done by using the Table Curve 2D. The preliminary conclusions indicate Andrews-s model with a maximum specific growth rate of the bacterium in the range of 0.8 h-1.

Keywords: bioprocess modeling, Pseudomonas aeruginosa, kinetic models,

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1685

Authors: Jelena Zagorska, Inga Ciprovica

Abstract:

The freezing point of milk is in important indicator of the milk quality. The freezing point of milk is determined primarily to prove milk adulteration with water and to determine the amount of water in it. Chemical composition and properties of milk, thermal treatment and presence of any substance can influence freezing point of product. There are different substances, which can be added to milk with main purpose to prolong shelf-life of raw milk. There are detergent, preservatives, formaldehyde, hydrogen peroxide, antibiotics, sodium carbonate, and hydrogen peroxide. Therefore the aim of the present study was to determine freezing point of milk, skimmed milk, pasteurized milk and milk with different substances (formaldehyde, antibiotics, sodium carbonate, hydrogen peroxide, disinfectant, and detergent) in different concentrations. The thermal treatment and different undesirable substances presence in milk have significant influence on freezing point of it.

Keywords: Antibiotics, freezing point, milk, pH, thermal treatment.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10318

Authors: Nabli L., Dhouibi H., Collart Dutilleul S., Craye E.

Abstract:

The existence of maximal durations drastically modifies the performance evaluation in Discrete Event Systems (DES). The same particularity may be found on systems where the associated constraints do not concern the time. For example weight measures, in chemical industry, are used in order to control the quantity of consumed raw materials. This parameter also takes a fundamental part in the product quality as the correct transformation process is based upon a given percentage of each essence. Weight regulation therefore increases the global productivity of the system by decreasing the quantity of rejected products. In this paper we present an approach based on mixing different characteristics theories, the fuzzy system and Petri net system to describe the behaviour. An industriel application on a tobacco manufacturing plant, where the critical parameter is the weight is presented as an illustration.

Keywords: Petri Net, Manufacturing systems, Performance evaluation, Fuzzy logic, Tolerant system.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1907

Authors: Saif N. Al-Bahry, Yahya M. Al-Wahaibi, Abdulkadir E. Elshafie, Ali S. Al-Bemani, Sanket J. Joshi

Abstract:

Environmental pollution is a global problem and best possible solution is identifying and utilizing native microorganisms. One possible application of microbial product -biosurfactant is in bioremediation of hydrocarbon contaminated sites. We have screened forty two different petroleum contaminated sites from Oman, for biosurfactant producing spore-forming bacterial isolates. Initial screening showed that out of 42 soil samples, three showed reduction in surface tension (ST) and interfacial tension (IFT) within 24h of incubation at 40°C. Out of those 3 soil samples, one was further selected for isolation of bacteria and 14 different bacteria were isolated in pure form. Of those 14 spore-forming, rod shaped bacteria, two showed highest reduction in ST and IFT in the range of 70mN/m to <35mN/m and 26.69mN/m to <9mN/m, respectively within 24h. These bacterial biosurfactants may be utilized for bioremediation of oil-spills.

Keywords: Bioremediation, biosurfactant, hydrocarbon pollution, spore-forming bacteria.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2395

Authors: Omid Ghassemi

Abstract:

As a by-product of its "cyberspace" status, electronic commerce is global, encompassing a whole range of B2C relationships which need to be approached with solutions provided at a local level while remaining viable when applied to global issues. Today, the European Union seems to be endowed with a reliable legal framework for consumer protection. A question which remains, however, is enforcement of this protection. This is probably a matter of time and awareness from both parties in the B2C relationship. Business should realize that enhancing trust in the minds of consumers is more than a question of technology; it is a question of best practice. Best practice starts with the online service of high street banks as well as with the existence of a secure, user-friendly and cost-effective payment system. It also includes the respect of privacy and the use of smart cards as well as enhancing privacy technologies and fair information practice. In sum, only by offering this guarantee of privacy and security will the consumer be assured that, in cyberspace, his/her interests will be protected in the same manner as in a traditional commercial environment.

Keywords: Consumer, Electronic, Jurisdiction, Payment

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1731

Authors: Ademeso, Odunyemi Anthony

Abstract:

The charnockitic and associated granitic rocks of Akure area were studied for their field and petrographic relationship's. The outcrops locations were plotted in Surfer 8. The granitic rock exhibits a porphyritic texture and outcrops in the north-eastern side of the study area while the charnockitics outcrop in the central/western part. An essentially dark coloured and fine grained intrusive exhibiting xenoliths and xenocrysts (plagioclase phenocrysts) of the granite outcrops between the granitic and charnockitic rocks. Mineralogically, the central rock combines the content of the other two indicating that it is most likely a product of their hybridization. The charnockitic magma is believed to have intruded and assimilated the granite substantially thereby contaminating itself and consequently emplacing the hybrid. The presented model of emplacement elucidates the hybridization proposal. Conclusively, the charnockitics are believed to be (a) younger than the granite, (b) of Pan-African age and (c) of igneous origin.

Keywords: Charnockitic rock, Hybrid rock, ImageJ, Xenocryst

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2997

Authors: Mudafara S Bengleil

Abstract:

Estimation of the magnitude and causes of poisoning was the objective of the current study. A retrospective study of medical records of all poisoning children admitted to Benghazi Children Hospital in Libya from January 2008 up to December 2010. Number of children admitted was 244; the age ranged from less than one to 13 years old. Most of cases were admitted with mild symptom and the majority of them were boys. Only few cases admitted to intensive care unit and there was no mortality recorded through the period of study. Age group 1 to 3 years (50.8%) had the highest frequency of admission and the peak of admission was during summer. The most common cause of admission was due to ingestion of medication (53.69%), House hold product exposure (26.64%) was the second causes of admission while, 19.67% of admissions were due to Food poisoning. Almost all admitted cases were accidental and medicines were the most consumed substances in addition, improper storage of toxic agents were the first risk factor of poisoning. Present results indicated that, children poisoning seems to be a common pediatric care problem which need to control and prevent.

Keywords: Children, hospital, poisoning.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1857

Authors: A. Tamošiūnas, P. Valatkevičius, V. Grigaitiene, V. Valinčius

Abstract:

The atmospheric pressure plasma torch with a direct current arc discharge stabilized by water vapor vortex was experimentally investigated. Overheated up to 450K water vapor was used as plasma forming gas. Plasma torch design is one of the most important factors leading to a stable operation of the device. The electrical and thermal characteristics of the plasma torch were determined during the experimental investigations. The design and the basic characteristics of the water vapor plasma torch are presented in the paper. Plasma torches with the electric arc stabilized by water vapor vortex provide special performance characteristics in some plasma processing applications such as thermal plasma neutralization and destruction of organic wastes enabling to extract high caloric value synthesis gas as by-product of the process. Syngas could be used as a surrogate fuel partly replacing the dependence on the fossil fuels or used as a feedstock for hydrogen, methanol production.

Keywords: Arc discharge, atmospheric pressure thermal plasma, plasma torch, water vapor.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4451

Authors: Tadayoshi Horita, Masakazu Akiba, Mina Terauchi, Tsuneo Kanno

Abstract:

This paper gives a consideration of the achievement of productive level parallel programming skills, based on the data of the graduation studies in the Polytechnic University of Japan. The data show that most students can achieve only parallel programming skills during the graduation study (about 600 to 700 hours), if the programming environment is limited to GPGPUs. However, the data also show that it is a very high level task that a student achieves productive level parallel programming skills during only the graduation study. In addition, it shows that the parallel programming environments for GPGPU, such as CUDA and OpenCL, may be more suitable for parallel computing education than other environments such as MPI on a cluster system and Cell.B.E. These results must be useful for the areas of not only software developments, but also hardware product developments using computer technologies.

Keywords: Parallel computing, programming education, GPU, GPGPU, CUDA, OpenCL, MPI, Cell.B.E.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1662

Authors: V. Arbabi , I. Ebrahimzadeh, H. Ghanbari, M.M. Kaykha

Abstract:

Horizontal continuous casting is widely used to produce semi-finished non-Ferrous products. Homogeneity in the metallurgical characteristics and mechanical properties for this product is vital for industrial application. In the present work, the microstructure and mechanical properties of a horizontal continuous cast two-phase brass billet have been studied. Impact strength and hardness variations were examined and the phase composition and porosity studied with image analysis software. Distinct differences in mechanical properties were observed between the upper, middle and lower parts of the billet, which are explained in terms of the morphology and size of the phase in the microstructure. Hardness variation in the length of billet is higher in upper area but impact strength is higher in lower areas.

Keywords: Horizontal Continuous Casting, Two-phase brasses, CuZn40Al1 alloy, Microstructure, Impact Strength.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2156

Authors: Pakorn Traiprasertpong, Apichit Svang-Ariyaskul

Abstract:

The production of ethyl tert-butyl ether (ETBE) was simulated through Aspen Plus. The objective of this work was to use the simulation results to be an alternative platform for ETBE production from naphtha cracking wastes for the industry to develop. ETBE is produced from isobutylene which is one of the wastes in naphtha cracking process. The content of isobutylene in the waste is less than 30% weight. The main part of this work was to propose a process to save the environment and to increase the product value by converting a great majority of the wastes into ETBE. Various processes were considered to determine the optimal production of ETBE. The proposed process increased ETBE production yield by 100% from conventional process with the purity of 96% weight. The results showed a great promise for developing this proposed process in an industrial scale.

Keywords: ETBE, process simulation, naphtha cracking, Aspen Plus

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5403

Authors: Yuzhi Cai

Abstract:

In this talk, we introduce a newly developed quantile function model that can be used for estimating conditional distributions of financial returns and for obtaining multi-step ahead out-of-sample predictive distributions of financial returns. Since we forecast the whole conditional distributions, any predictive quantity of interest about the future financial returns can be obtained simply as a by-product of the method. We also show an application of the model to the daily closing prices of Dow Jones Industrial Average (DJIA) series over the period from 2 January 2004 - 8 October 2010. We obtained the predictive distributions up to 15 days ahead for the DJIA returns, which were further compared with the actually observed returns and those predicted from an AR-GARCH model. The results show that the new model can capture the main features of financial returns and provide a better fitted model together with improved mean forecasts compared with conventional methods. We hope this talk will help audience to see that this new model has the potential to be very useful in practice.

Keywords: DJIA, Financial returns, predictive distribution, quantile function model.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1622

Authors: Huang Shengqin, Xiao Hong

Abstract:

LES with mixed subgrid-scale model has been used to simulate aerodynamic performance of hypersonic configuration. The simulation was conducted to replicate conditions and geometry of a model which has been previously tested. LES Model has been successful in predict pressure coefficient with the max error 1.5% besides afterbody. But in the high Mach number condition, it is poor in predict ability and product 12.5% error. The calculation error are mainly conducted by the distribution swirling. The fact of poor ability in the high Mach number and afterbody region indicated that the mixed subgrid-scale model should be improved in large eddied especially in hypersonic separate region. In the condition of attach and sideslip flight, the calculation results have waves. LES are successful in the prediction the pressure wave in hypersonic flow.

Keywords: Hypersonic, LES, mixed Subgrid-scale model, experiment.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1555

Authors: T. Yuri M. Zagloel, Inaki M. Hakim, A. M. Syarafi

Abstract:

Manufacturing process has been considered as one of the most important activity in business process. It correlates with productivity and quality of the product so industries could fulfill customer’s demand. With the increasing demand from customer, industries must improve their manufacturing ability such as shorten lead-time and reduce wastes on their process. Lean manufacturing has been considered as one of the tools to waste elimination in manufacturing or service industry. Workforce development is one practice in lean manufacturing that can reduce waste generated from operator such as waste of unnecessary motion. Anthropometric approach is proposed to determine the recommended measurement in operator’s work area. The method will get some dimensions from Indonesia people that related to piston workstation. The result from this research can be obtained new design for the work area considering ergonomic aspect.

Keywords: Adjustable, anthropometric, ergonomic, waste.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1586

Authors: Wisutmethangoon S., Denmud N., Sikong L.

Abstract:

The fabrication of porous NiTi shape memory alloys (SMAs) from elemental powder compacts was conducted by selfpropagating high temperature synthesis (SHS). Effects of the preheating temperature and the chamber pressure on the combustion characteristics as well as the final morphology and the composition of products were studied. The samples with porosity between 56.4 and 59.0% under preheating temperature in the range of 200-300°C and Ar-gas chamber pressure of 138 and 201 kPa were obtained. The pore structures were found to be dissimilar only in the samples processed with different preheating temperature. The major phase in the porous product is NiTi with small amounts of secondary phases, NiTi2 and Ni4Ti3. The preheating temperature and the chamber pressure have very little effect on the phase constituent. While the combustion temperature of the sample was notably increased by increasing the preheating temperature, they were slightly changed by varying the chamber pressure.

Keywords: Combustion synthesis, porous materials, self propagating high temperature synthesis, shape memory alloy.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1720