Search results for: forging process

Authors: Youngji Yoo, Seung Hwan Park, Daewoong An, Sung-Shick Kim, Jun-Geol Baek

Abstract:

The yield management system is very important to produce high-quality semiconductor chips in the semiconductor manufacturing process. In order to improve quality of semiconductors, various tests are conducted in the post fabrication (FAB) process. During the test process, large amount of data are collected and the data includes a lot of information about defect. In general, the defect on the wafer is the main causes of yield loss. Therefore, analyzing the defect data is necessary to improve performance of yield prediction. The wafer bin map (WBM) is one of the data collected in the test process and includes defect information such as the fail bit patterns. The fail bit has characteristics of spatial point patterns. Therefore, this paper proposes the feature extraction method using the spatial point pattern analysis. Actual data obtained from the semiconductor process is used for experiments and the experimental result shows that the proposed method is more accurately recognize the fail bit patterns.

Keywords: semiconductor, wafer bin map, feature extraction, spatial point patterns, contour map

Procedia PDF Downloads 356

Authors: Efri Mardawati, Ronny Purwadi, Made Tri Ari Penia Kresnowati, Tjandra Setiadi

Abstract:

EFB are mainly composed of cellulose (≈ 43%), hemicellulose (≈ 23%) and lignin (≈20%). The palm oil empty fruit bunches (EFB) is the lignosellulosic waste from crude palm oil industries mainly compose of (≈ 43%), hemicellulose (≈ 23%) and lignin (≈20%). Xylan, a polymer made of pentose sugar xylose and the most abundant component of hemicellulose in plant cell wall. Further xylose can be used as a raw material for production of a wide variety of chemicals such as xylitol, which is extensively used in food, pharmaceutical and thin coating applications. Currently, xylose is mostly produced from xylan via chemical hydrolysis processes. However, these processes are normally conducted at a high temperature and pressure, which is costly, and the required downstream processes are relatively complex. As an alternative method, enzymatic hydrolysis of xylan to xylose offers an environmentally friendly biotechnological process, which is performed at ambient temperature and pressure with high specificity and at low cost. This process is catalysed by xylanolytic enzymes that can be produced by some fungal species such as Aspergillus niger, Penicillium crysogenum, Tricoderma reseei, etc. Fungal that will be used to produce crude xylanase enzyme in this study is T. Viride ITB CC L.67. It is the purposes of this research to study the influence of pretreatment of EFB for the enzymatic hydrolysis process, optimation of temperature and pH of the hydrolysis process, the influence of substrate and enzyme concentration to the enzymatic hydrolysis process, the dynamics of hydrolysis process and followingly to study the kinetics of this process. Xylose as the product of enzymatic hydrolysis process analyzed by HPLC. The results show that the thermal pretreatment of EFB enhance the enzymatic hydrolysis process. The enzymatic hydrolysis can be well approached by the Michaelis Menten kinetic model, and kinetic parameters are obtained from experimental data.

Keywords: oil palm empty fruit bunches (EFB), xylose, enzymatic hydrolysis, kinetic modelling

Procedia PDF Downloads 366

Authors: José Luiz da Silva Neto, Renato Sipelli Silva, Érick Aragão Ribeiro

Abstract:

The automation of industrial processes plays a vital role in industries today, becoming an integral and important part of the industrial process and modern production. The process control systems are designed to maximize production, reduce costs and minimize risks in production. However, these systems are generally not deployed methodologies and planning. So that this article describes the development of an automation system of a kitchen preparation of chemicals in the textile industry based on a retrofitting methodology that provides more quality into the process at a lower cost.

Keywords: automation, textile industry, kitchen chemical, information integration

Procedia PDF Downloads 401

Authors: Hartomo Soewardi, Bachtiar Jouhari

Abstract:

Ineffectiveness and inefficiency of the building permit process in Indonesia still becomes a major problems for people to apply. Long time of service, the complicated administration process, and an expensive fees are a process that causing a dissatisfaction and discomfort for applicant. Therefore, it is critical to improve the quality of service of building permit system. Objectives of this research is to develop a better process of the system to improve productivity and quality service. Lean six sigma concept by using DMAIC procedures was used to analyze the existing system. Moreover, improvement of the system was conducted by using the Axiomatic Design method. Verification test was done to test the hypothesis of the proposed system design. Result of this research shows that proposed system can produce increasing 61.8% of efficiency on service time, and more effective and easier.

Keywords: axiomatic design, bbuilding permit system, DMAIC, Lean Six Sigma

Procedia PDF Downloads 310

Authors: Alibi Kilybay, Emad Alhseinat, Ibrahim Mustafa, Abdulfahim Arangadi, Pei Shui, Faisal Almarzooqi

Abstract:

In this work, the electromagnetic field has been used for improving the performance of the capacitive deionization process. The effect of electromagnetic fields on the efficiency of the capacitive deionization (CDI) process was investigated experimentally. The results showed that treating the feed stream of the CDI process using an electromagnetic field can enhance the electrosorption capacity from 20% up to 70%. The effect of the degree of time of exposure, concentration, and type of ions have been examined. The electromagnetic field enhanced the salt adsorption capacity (SAC) of the Ca²⁺ ions by 70%, while the SAC enhanced 20% to the Na⁺ ions. It is hypnotized that the electrometric field affects the hydration shell around the ions and thus reduces their effective size and enhances the mass transfer. This reduction in ion effective size and increase in mass transfer enhanced the electrosorption capacity and kinetics of the CDI process.

Keywords: capacitive deionization, desalination, electromagnetic treatment, water treatment

Procedia PDF Downloads 228

Authors: B. SahaRoy, T. Medhi, S. C. Saha

Abstract:

To understand the friction stir welding process, it is very important to know the nature of the material flow in and around the tool. The process is a combination of both thermal as well as mechanical work i.e it is a coupled thermo-mechanical process. Numerical simulations are very much essential in order to obtain a complete knowledge of the process as well as the physics underlying it. In the present work a model based approach is adopted in order to study material flow. A thermo-mechanical based CFD model is developed using a Finite Element package, Comsol Multiphysics. The fluid flow analysis is done. The model simultaneously predicts shear strain fields, shear strain rates and shear stress over the entire workpiece for the given conditions. The flow fields generated by the streamline plot give an idea of the material flow. The variation of dynamic viscosity, velocity field and shear strain fields with various welding parameters is studied. Finally the result obtained from the above mentioned conditions is discussed elaborately and concluded.

Keywords: AA6061-T6, CFD modelling, friction stir welding, material flow

Procedia PDF Downloads 495

Authors: Alonggot Limcharoen, Jintana Wannarat, Vorawat Panich

Abstract:

This study aims to investigate the balancing of the number of operators (Line Balancing technique) in the production line of hard disk drive components in order to increase efficiency. At present, the trend of using hard disk drives has continuously declined leading to limits in a company’s revenue potential. It is important to improve and develop the production process to create market share and to have the ability to compete with competitors with a higher value and quality. Therefore, an effective tool is needed to support such matters. In this research, the Arena program was applied to analyze the results both before and after the improvement. Finally, the precedent was used before proceeding with the real process. There were 14 work stations with 35 operators altogether in the RA production process where this study was conducted. In the actual process, the average production time was 84.03 seconds per product piece (by timing 30 times in each work station) along with a rating assessment by implementing the Westinghouse principles. This process showed that the rating was 123% underlying an assumption of 5% allowance time. Consequently, the standard time was 108.53 seconds per piece. The Takt time was calculated from customer needs divided by working duration in one day; 3.66 seconds per piece. Of these, the proper number of operators was 30 people. That meant five operators should be eliminated in order to increase the production process. After that, a production model was created from the actual process by using the Arena program to confirm model reliability; the outputs from imitation were compared with the original (actual process) and this comparison indicated that the same output meaning was reliable. Then, worker numbers and their job responsibilities were remodeled into the Arena program. Lastly, the efficiency of production process enhanced from 70.82% to 82.63% according to the target.

Keywords: hard disk drive, line balancing, ECRS, simulation, arena program

Procedia PDF Downloads 203

Authors: Jamaludin Jamaludin, Suparji Suparji, Lilik Anifah, I. Gusti Putu Asto Buditjahjanto, Eppy Yundra

Abstract:

Learning media is an important and main component in the learning process. By using currently available media, cadets still have difficulty understanding how the piston engine works, so they are not able to apply these concepts appropriately. This study aims to examine the development of interactive media for piston engine courses in order to improve student learning outcomes. The research method used is a literature study of several articles, journals and proceedings of interactive media development results from 2010-2020. The results showed that the development of interactive media is needed to support the learning process and influence the cognitive abilities of students. With this interactive media, learning outcomes can be improved and the learning process can be effective.

Keywords: interactive media, learning outcomes, learning process, literature study

Procedia PDF Downloads 124

Authors: C. Patrascioiu, Cao Minh Ahn

Abstract:

The paper presents the research evolution in the propylene – propane distillation process, especially for the distillation columns equipped with heat pump. The paper is structured in three parts: separation of the propylene-propane mixture, steady state process modeling, and quality control systems. The first part is dedicated to state of art of the two distillation processes. The second part continues the author’s researches of the steady state process modeling. There has been elaborated a software simulation instrument that may be used to dynamic simulation of the process and to design the quality control systems. The last part presents the research of the control systems, especially for quality control systems.

Keywords: absorption, distillation, heat pump, Unisim design

Procedia PDF Downloads 314

Authors: Nadia K. Thalji

Abstract:

In the timeless tapestry of human culture, theater, mythology, and psychology intersect to weave narratives that transcend temporal and spatial boundaries. For millennia, actors have stood as guardians of intuitive wisdom, their craft serving as a conduit for the collective unconscious. This paper embarks on a journey through the realms of creative expression, melding the insights of cross-cultural psychology with the mystical allure of serendipity and synchronicity. At the nexus of these disciplines lies the enigmatic process of active imagination, a gateway to the depths of the psyche elucidated by Jung. Within the hallowed confines of the black box theater at the Department of Performing Arts, UFRGS University in Brazil, this study unfolds. Over the span of four months, a cadre of artists embarked on a voyage of exploration, harnessing the powers of imagery, movement, sound, and dreams to birth a performance that resonated with the echoes of ancient wisdom. Drawing inspiration from the fabled Oracle of Delphi and the priestesses who once dwelled within its sacred precincts, the production delves into the liminal spaces where myth and history intertwine. Through the alchemy of storytelling, participants navigate the labyrinthine corridors of cultural memory, unraveling the threads that bind the past to the present. Central to this endeavor is the phenomenon of synchronicity, wherein seemingly disparate elements coalesce in a dance of cosmic resonance. Serendipity becomes a guiding force, leading actors and audience alike along unexpected pathways of discovery. As the boundaries between performer and spectator blur, the performance becomes a crucible wherein individual narratives merge to form a collective tapestry of shared experience. Yet, beneath the surface of spectacle lies a deeper truth: the exploration of the spiritual dimensions of artistic expression. Through intuitive inquiry and embodied practice, artists tap into reservoirs of insight that transcend rational comprehension. In the communion of minds and bodies, the stage becomes a sacred space wherein the numinous unfolds in all its ineffable glory. In essence, this paper serves as a testament to the transformative power of the creative act. Across cultures and epochs, the theater has served as a crucible wherein humanity grapples with the mysteries of existence. Through the lens of cross-cultural psychology, we glimpse the universal truths that underlie the myriad manifestations of human creativity. As we navigate the turbulent currents of modernity, the wisdom of the ancients beckons us to heed the call of the collective unconscious. In the synthesis of myth and meaning, we find solace amidst the chaos, forging connections that transcend the boundaries of time and space. And in the sacred precincts of the theater, we discover the eternal truth that art is, and always shall be, the soul's journey into the unknown.

Keywords: theater, mythology, cross-cultural, synchronicity, creativity, serendipity, spiritual

Procedia PDF Downloads 38

Authors: Ha-Guk Jeong, Jong-Beom Lee

Abstract:

Cladding process is very typical technology for manufacturing composite materials by the hydrostatic extrusion. Because there is no friction between the metal and the container, it can be easily obtained in uniform flow during the deformation. The general manufacturing process for a metal-matrix composite in the solid state, mixing metal powders and ceramic powders with a suited volume ratio, prior to be compressed or extruded at the cold or hot condition in a can. Since through a plurality of unit processing steps of dispersing the materials having a large difference in their characteristics and physical mixing, the process is complicated and leads to non-uniform dispersion of ceramics. It is difficult and hard to reach a uniform ideal property in the coherence problems at the interface between the metal and the ceramic reinforcements. Metal hybrid composites, which presented in this report, are manufactured through the traditional plastic deformation processes like hydrostatic extrusion, caliber-rolling, and drawing. By the previous process, the realization of uniform macro and microstructure is surely possible. In this study, as a constituent material, aluminum, copper, and titanium have been used, according to the component ratio, excellent characteristics of each material were possible to produce a metal hybrid composite that appears to maximize. MgB₂ superconductor wire also fabricated via the same process. It will be introduced to their unique artistic and thermal characteristics.

Keywords: cladding process, metal-hybrid composites, hydrostatic extrusion, electronic/thermal characteristics

Procedia PDF Downloads 159

Authors: Mohammad Reza Ostad Ali Naghi Kashani

Abstract:

Nowadays, the amounts of companies which tend to have an Enterprise Resource Planning (ERP) application are increasing. Although ERP projects are expensive, time consuming, and complex, there are some successful experiences. These days, developing countries are striving to implement ERP projects successfully; however, there are many obstacles. Therefore, these projects would be failed or partially failed. This paper concerns the implementation of a successful ERP implementation, IFS, in Iran at Dana Geophysics Company (DGC). After a short review of ERP and ERP market in Iran, we propose a three phases deployment methodology (phase 1: Preparation and Business Process Management (BPM) phase 2: implementation and phase 3: testing, golive-1 (pilot) and golive-2 (final)). Then, we present five guidelines (Project Management, Change Management, Business Process Management (BPM), Training& Knowledge Management, and Technical Management), which were chose as work streams. In this case study we present lessons learned in Project management and Business process Management.

Keywords: business process management, critical success factors, ERP, project management

Procedia PDF Downloads 460

Authors: Amaraporn Puraya, Roongtiva Boonpracom, Somsak Thojampa, Sirikanok Klankhajhon, Kittisak Kumpeera

Abstract:

The objective of this qualitative research was to study the elderly health care process by community participation. Data were collected by quality research methods, including secondary data study, observation, in-depth interviews, and focus group discussions and analyzed by content analysis, reflection and review of information. The research results pointed out that the important elderly health care process by community participation consisted of 2 parts, namely the community participation development process in elderly health care and the outcomes from the participation development process. The community participation development process consisted of 4 steps as follows: 1) Building the leadership team, an important social capital of the community, which started from searching for both formal and informal leaders by giving the opportunity for public participation and creating clear agreements defining roles, duties and responsibilities; 2) investigating the problems and the needs of the community, 3) designing the elderly health care activities under the concept of self-care potential development of the elderly through participation in community forums and meetings to exchange knowledge with common goals, plans and operation and 4) the development process of sustainable health care agreement at the local level, starting from opening communication channels to create awareness and participation in various activities at both individual and group levels as well as pushing activities/projects into the community development plan consistent with the local administration policy. The outcomes from the participation development process were as follows. 1) There was the integration of the elderly for doing the elderly health care activities/projects in the community managed by the elderly themselves. 2) The service system was changed from the passive to the proactive one, focusing on health promotion rather than treating diseases or illnesses. 3) The registered nurses / the public health officers can provide care for the elderly with chronic illnesses through the implementation of activities/projects of elderly health care so that the elderly can access the services more. 4) The local government organization became the main mechanism in driving the elderly health care process by community participation.

Keywords: elderly health care process, community participation, elderly, Thailand

Procedia PDF Downloads 180

Authors: Japinder Wadhawan, Pradeep Rajan, Alok K. Saran, Navdeep S. Sidhu, Daanvir K. Dhir

Abstract:

Currently, research focus in the development of agricultural equipment and tractor parts in India is innovation and use of alternate materials like austempered ductile iron (ADI). Three-point linkage mechanism of the tractor is susceptible to unpredictable load conditions in the field, and one of the critical components vulnerable to failure is lift arm. Conventionally, lift arm is manufactured either by forging or casting (SG Iron) and main objective of the present work is to reduce the failure occurrences in the lift arm, which is achieved by changing the manufacturing material, i.e ADI, without changing existing design. Effect of four pertinent variables of manufacturing ADI, viz. austenitizing temperature, austenitizing time, austempering temperature, austempering time, was investigated using Taguchi method for design of experiments. To analyze the effect of parameters on the mechanical properties, mean average and signal-to-noise (S/N) ratio was calculated based on the design of experiments with L9 orthogonal array and the linear graph. The best combination for achieving the desired mechanical properties of lift arm is austenitization at 860°C for 90 minutes and austempering at 350°C for 60 minutes. Results showed that the developed component is having 925 MPA tensile strength, 7.8 per cent elongation and 120 joules toughness making it more suitable material for lift arm manufacturing. The confirmatory experiment has been performed and found a good agreement between predicted and experimental value. Also, the CAD model of the existing design was developed in computer aided design software, and structural loading calculations were performed by a commercial finite element analysis package. An optimized shape of the lift arm has also been proposed resulting in light weight and cheaper product than the existing design, which can withstand the same loading conditions effectively.

Keywords: austempered ductile iron, design of experiment, finite element analysis, lift arm

Procedia PDF Downloads 214

Authors: Krešimir Fertalj, Mladen Matejaš

Abstract:

In turbulent modern economy, the companies need to properly manage their business processes. Well defined and stable business processes ensure the security of crucial data and application, and provide a quality product or service to the end customer. On the other side constant changes on the market, new regulatory provisions and emerging new technologies require the need of issuing prompt and effective changes of business process. In this article, we explore the use of agile principles in working with business process management (BPM) solutions. We deal with difficulties in BPM development cycle, review the benefits of using agility and choose the basic agile principles that ensure the success of a BPM project.

Keywords: agile development, BPM environment, Kanban, SCRUM, XP

Procedia PDF Downloads 299

Authors: Akshay Paranjape, Nils Plettenberg, Robert Schmitt

Abstract:

Producing faulty products can be costly for manufacturing companies and wastes resources. To reduce scrap rates in manufacturing, process parameters can be optimized using machine learning. Thus far, research mainly focused on optimizing specific processes using traditional algorithms. To develop a framework that enables real-time optimization based on a predictive model for an arbitrary production process, this study explores the application of reinforcement learning (RL) in this field. Based on a thorough review of literature about RL and process parameter optimization, a model based on maximum a posteriori policy optimization that can handle both numerical and categorical parameters is proposed. A case study compares the model to state–of–the–art traditional algorithms and shows that RL can find optima of similar quality while requiring significantly less time. These results are confirmed in a large-scale validation study on data sets from both production and other fields. Finally, multiple ways to improve the model are discussed.

Keywords: reinforcement learning, production process optimization, evolutionary algorithms, policy optimization, actor critic approach

Procedia PDF Downloads 69

Authors: K. Indra Gandhi

Abstract:

Wireless Sensor Networks (WSNs) have always been characterized for application-specific sensing, relaying and collection of information for further analysis. However, software development was not considered as a separate entity in this process of data collection which has posed severe limitations on the software development for WSN. Software development for WSN is a complex process since the components involved are data-driven, network-driven and application-driven in nature. This implies that there is a tremendous need for the separation of concern from the software development perspective. A layered approach for developing data acquisition design based on Model Driven Development (MDD) has been proposed as the sensed data collection process itself varies depending upon the application taken into consideration. This work focuses on the layered view of the data acquisition process so as to ease the software point of development. A metamodel has been proposed that enables reusability and realization of the software development as an adaptable component for WSN systems. Further, observing users perception indicates that proposed model helps in improving the programmer's productivity by realizing the collaborative system involved.

Keywords: data acquisition, model-driven development, separation of concern, wireless sensor networks

Procedia PDF Downloads 410

Authors: Viliam Makis, Farnoosh Naderkhani, Leila Jafari

Abstract:

In this paper, we present a model and an algorithm for the calculation of the optimal control limit, average cost, sample size, and the sampling interval for an optimal Bayesian chart to control the proportion of defective items produced using a semi-Markov decision process approach. Traditional p-chart has been widely used for controlling the proportion of defectives in various kinds of production processes for many years. It is well known that traditional non-Bayesian charts are not optimal, but very few optimal Bayesian control charts have been developed in the literature, mostly considering finite horizon. The objective of this paper is to develop a fast computational algorithm to obtain the optimal parameters of a Bayesian p-chart. The decision problem is formulated in the partially observable framework and the developed algorithm is illustrated by a numerical example.

Keywords: Bayesian control chart, semi-Markov decision process, quality control, partially observable process

Procedia PDF Downloads 295

Authors: Baghdasaryan Marinka

Abstract:

Monitoring the distribution of electric power consumption in the technological process of ore grinding is conducted. As a result, the impacts of the mill filling rate, the productivity of the ore supply, the volumetric density of the grinding balls, the specific density of the ground ore, and the relative speed of the mill rotation on the specific consumption of electric power have been studied. The power and technological factors affecting the reactive power generated by the synchronous motors, operating within the technological scheme are studied. A block diagram for evaluating the power consumption modes of the technological process is presented, which includes the analysis of the technological scheme, the determination of the place and volumetric density of the ore-grinding mill, the evaluation of the technological and power factors affecting the energy saving process, as well as the assessment of the electric power standards.

Keywords: electric power standard, factor, ore grinding, power consumption, reactive power, technological

Procedia PDF Downloads 526

Authors: Wanwimon Mekwimon

Abstract:

Drug addiction is a serious problem in Thailand which has occurred continuously and repeatedly and enormously impacting health and economy of drug users. The indigenous wisdom and folk medicine is an attractive alternative choice, especially in detoxification and rehabilitation period. There are two objectives: First is to study about rehabilitation process and the curing for drug eaters and 2nd is to investigate the effectiveness of the curing and rehabilitation process by indigenous wisdom at Tamkrabok monastery, Pra-Puttabat district, Saraburi province. The main informants are 10 curers, 15 patients and 17 after-1-year rehabilitators. In the process, the semi-structured questionnaire is administered, the data are analyzed and proved by triangulation. The curing and rehabilitation process which use herbal remedies has a period of 15 days (5 days for detoxification and 10 days for recovery period) and the occupational training and self-consciousness awakening were delivered. The follow-up process includes twice-a-month recall for 6 months, follow-up letters and in depth interview with their families. The outcome of 1 year post-treatment was 94% (16 from 17). There are many reasons for not relapsing: the recovering patients have drawn on their inner strength, self-awareness and coping skill as well as their family and social support while rehabilitation process which includes difficulties in contacting with family members. They can void themselves from high risk situations to relapse. Recommendations: The follow-up system should be improved for continuous quality improvement, there should be the qualification standard for herbal remedies and the comparison among rehabilitation process of Tamkrabok and another methods are to be guideline for the further development.

Keywords: rehabilitation, drug addiction, Thai indigenous knowledge, herbal remedies

Procedia PDF Downloads 227

Authors: Terence Soule, Tami Al Ghamdi

Abstract:

To study how the partial knowledge transfer may affect the Genetic Algorithm (GA) performance, we model the Transfer Learning (TL) process using GA as the model solver. The objective of the TL is to transfer the knowledge from one problem to another related problem. This process imitates how humans think in their daily life. In this paper, we proposed to study a case where the knowledge transferred from the S problem has less information than what the T problem needs. We sampled the transferred population using different strategies of TL. The results showed transfer part of the knowledge is helpful and speeds the GA process of finding a solution to the problem.

Keywords: transfer learning, partial transfer, evolutionary computation, genetic algorithm

Procedia PDF Downloads 105

Authors: Mani Ram Sharma

Abstract:

We live in a busy world with sudden distractions and many things to think about. The rapid speed of science and technology keeps our world in constant motion. Students leaving the classroom after being taught by the teachers are thinking about a thousand things: "Did I understand what teacher taught?" However, when they come into the classroom, as teachers, we expect them to be ready to learn, ready to receive information, and retain it. There is a question that how can learners do this with so much in their learning process. It is obliviously with the use of innovation in the classroom. It fosters the students to learn innovatively to establish learner's autonomy. This article outlines the role, need, and process of innovation in the language classroom and teaching.

Keywords: distraction, foster, innovation, learner's autonomy, retainment

Procedia PDF Downloads 248

Authors: John Knight, Fuchun Li, Yan Xu

Abstract:

Based on a new method of the nonparametric estimator of the drift function, we propose a consistent test for the parametric specification of the drift function in the short rate diffusion process using observations from a panel of yields. The test statistic is shown to follow an asymptotic normal distribution under the null hypothesis that the parametric drift function is correctly specified, and converges to infinity under the alternative. Taking the daily 7-day European rates as a proxy of the short rate, we use our test to examine whether the drift of the short rate diffusion process is linear or nonlinear, which is an unresolved important issue in the short rate modeling literature. The testing results indicate that none of the drift functions in this literature adequately captures the dynamics of the drift, but nonlinear specification performs better than the linear specification.

Keywords: diffusion process, nonparametric estimation, derivative security price, drift function and volatility function

Procedia PDF Downloads 345

Authors: Yong-Jun Jeon, Hyung-Pil Park, Min-Jae Song, Baeg-Soon Cha

Abstract:

Following the recent trend of having increased demand in producing lighter-weight car bodies for improvement of automobile safety and gas mileage, there is a forming method that makes use of hot-stamping technique, which satisfies all conditions mentioned above. Hot-stamping is a forming technique with advantages of excellent formability, good dimensional precision and others since it is a process in which steel plates are heated up to temperatures of at least approximately 900°C after which forming is conducted in die at room temperature followed by rapid cooling. In addition, it has characteristics of allowing for improvement in material strength through achievement of quenching effect by having simultaneous forming and rapid cooling of material of high temperatures. However, there is insufficient information on the changes in material strength according to changes in material temperature with regards to material heating method and forming process in hot-stamping. Accordingly, this study aims to design and press die for T-type product of the scale models of the center pillar and to understand the changes in material strength in relation to changes in forming methods of hot-stamping process. Thus in order to understand the changes in material strength due to quenching effect among the hot-stamping process, material strength and material forming precision were to be studied while varying the forming and forming method when forming. For test methods, material strength was observed by using boron steel that has boron additives, which was heated up to 950°C, after which it was transferred to a die and was cooled down to material temperature of 400°C followed by air cooling process. During the forming and cooling process here, experiment was conducted with forming parameters of 2 holding rates and 3 flange heating rates wherein changing appearance in material strength according to changes forming method were observed by verifying forming strength and forming precision for each of the conditions.

Keywords: hot-stamping, formability, quenching, forming, press die, forming methods

Procedia PDF Downloads 440

Authors: L. A. Toro, N. Prieto, J. J. Vargas

Abstract:

There are many control charts for monitoring mean and variance. Among these, the X y R, X y S, S2 Hotteling and Shewhart control charts, for mentioning some, are widely used for monitoring mean a variance in industrial processes. In particular, the Shewhart charts are based on the information about the process contained in the current observation only and ignore any information given by the entire sequence of points. Moreover, that the Shewhart chart is a control chart without memory. Consequently, Shewhart control charts are found to be less sensitive in detecting smaller shifts, particularly smaller than 1.5 times of the standard deviation. These kind of small shifts are important in many industrial applications. In this study and effective alternative to Shewhart control chart was implemented. In case of univariate process an Exponentially Moving Average (EWMA) control chart was developed and Multivariate Exponentially Moving Average (MEWMA) control chart in case of multivariate process. Both of these charts were based on memory and perform better that Shewhart chart while detecting smaller shifts. In these charts, information the past sample is cumulated up the current sample and then the decision about the process control is taken. The mentioned characteristic of EWMA and MEWMA charts, are of the paramount importance when it is necessary to control industrial process, because it is possible to correct or predict problems in the processes before they come to a dangerous limit.

Keywords: control charts, multivariate exponentially moving average (MEWMA), exponentially moving average (EWMA), industrial control process

Procedia PDF Downloads 329

Authors: G. Krishna Mohana Rao, P. Ravi Kumar

Abstract:

Milling is the process of removing unwanted material with suitable tool. Even though the milling process is having wider application, the vibration of machine tool and work piece during the process produces chatter on the products. Various methods of preventing the chatter have been incorporated into machine tool systems. Damper is cut into equal number of parts. Each part is called as finger. Multiple fingers were inserted in the hollow portion of the shank to reduce tool vibrations. In the present work, nonlinear static and dynamic analysis of the damper inserted end milling cutter used to reduce the chatter was done. A comparison is made for the milling cutter with multiple dampers. Surface roughness was determined by machining with multiple finger inserted milling cutters.

Keywords: damping inserts, end milling, vibrations, nonlinear dynamic analysis, number of fingers

Procedia PDF Downloads 499

Authors: Sajjad Esmaeili, Robert Krause, Lukas Gerlich, Alireza Mohammadian Kia, Benjamin Uhlig

Abstract:

This investigation aims to develop the feasible and qualitative process parameters for the thin films fabrication into ultra-large through-silicon-vias (TSVs) as vertical interconnections. The focus of the study is on TSV metallization and its challenges employing new materials for the purpose of rapid signal propagation in the microsystems technology. Cobalt metal-organic chemical vapor deposition (Co-MOCVD) process enables manufacturing an adhesive and excellent conformal ultra-thin film all the way through TSVs in comparison with the conventional non-conformal physical vapor deposition (PVD) process of copper (Cu) seed layer. Therefore, this process provides a Cu seed-free layer which is capable of direct Cu electrochemical deposition (Cu-ECD) on top of it. The main challenge of this metallization module is to achieve the proper alternative seed layer with less roughness, sheet resistance and granular organic contamination (e.g. carbon) which intensify the Co corrosion under the influence of Cu electrolyte.

Keywords: Cobalt MOCVD, direct Cu electrochemical deposition (ECD), metallization technology, through-silicon-via (TSV)

Procedia PDF Downloads 131

Authors: Navajyoti Panda, R. S. Pawar

Abstract:

In this study, process parameters like punch angle, die opening, grain direction, and pre-bend condition of the strip for deep draw of high strength low alloy steel HSLA 420 are investigated. The finite element method (FEM) in association with the Taguchi and the analysis of variance (ANOVA) techniques are carried out to investigate the degree of importance of process parameters in V-bending process for HSLA 420&ST12 grade material. From results, it is observed that punch angle had a major influence on the spring-back. Die opening also showed very significant role on spring back. On the other hand, it is revealed that grain direction had the least impact on spring back; however, if strip from flat sheet is taken, then it is less prone to spring back as compared to the strip from sheet metal coil. HyperForm software is used for FEM simulation and experiments are designed using Taguchi method. Percentage contribution of the parameters is obtained through the ANOVA techniques.

Keywords: bending, spring-back, v-bending, FEM, Taguchi, HSLA 420 and St12 materials, HyperForm, profile projector

Procedia PDF Downloads 167

Authors: Sachin Kamble, Shradha Gawankar

Abstract:

This paper presents the findings of successful implementation of Business Process Reengineering (BPR) of cement dispatch activities in a cement manufacturing plant located in India. Simulation model was developed for the purpose of identifying and analyzing the areas for improvement. The company was facing a problem of low throughput rate and subsequent forced stoppages of the plant leading to a high production loss of 15000MT per month. It was found from the study that the present systems and procedures related to the in-plant logistics plant required significant changes. The major recommendations included process improvement at the entry gate, reducing the cycle time at the security gate and installation of an additional weigh bridge. This paper demonstrates how BPR can be implemented for improving the in-plant logistics process. Various recommendations helped the plant to increase its throughput by 14%.

Keywords: in-plant logistics, cement logistics, simulation modelling, business process re-engineering, supply chain management

Procedia PDF Downloads 273

Authors: Fadi Eleiwi, Taous Meriem Laleg-Kirati

Abstract:

This paper presents a complete dynamic modeling of a membrane distillation process. The model contains two consistent dynamic models. A 2D advection-diffusion equation for modeling the whole process and a modified heat equation for modeling the membrane itself. The complete model describes the temperature diffusion phenomenon across the feed, membrane, permeate containers and boundary layers of the membrane. It gives an online and complete temperature profile for each point in the domain. It explains heat conduction and convection mechanisms that take place inside the process in terms of mathematical parameters, and justify process behavior during transient and steady state phases. The process is monitored for any sudden change in the performance at any instance of time. In addition, it assists maintaining production rates as desired, and gives recommendations during membrane fabrication stages. System performance and parameters can be optimized and controlled using this complete dynamic model. Evolution of membrane boundary temperature with time, vapor mass transfer along the process, and temperature difference between membrane boundary layers are depicted and included. Simulations were performed over the complete model with real membrane specifications. The plots show consistency between 2D advection-diffusion model and the expected behavior of the systems as well as literature. Evolution of heat inside the membrane starting from transient response till reaching steady state response for fixed and varying times is illustrated.

Keywords: membrane distillation, dynamical modeling, advection-diffusion equation, thermal equilibrium, heat equation

Procedia PDF Downloads 247