Search results for: overhaul time
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 17774

Search results for: overhaul time

17774 Theory of Constraints: Approach for Performance Enhancement and Boosting Overhaul Activities

Authors: Sunil Dutta

Abstract:

Synchronization is defined as ‘the sequencing and re-sequencing of all relative and absolute activities in time and space and continuous alignment of those actions with purposeful objective in a complex and dynamic atmosphere. In a complex and dynamic production / maintenance setup, no single group can work in isolation for long. In addition, many activities in projects take place simultaneously at the same time. Work of every section / group is interwoven with work of others. The various activities / interactions which take place in production / overhaul workshops are interlinked because of physical requirements (information, material, workforces, equipment, and space) and dependencies. The activity sequencing is determined by physical dependencies of various department / sections / units (e.g., inventory availability must be ensured before stripping and disassembling of equipment), whereas resource dependencies do not. Theory of constraint facilitates identification, analyses and exploitation of the constraint in methodical manner. These constraints (equipment, manpower, policies etc.) prevent the department / sections / units from getting optimum exploitation of available resources. The significance of theory of constraints for achieving synchronization at overhaul workshop is illustrated in this paper.

Keywords: synchronization, overhaul, throughput, obsolescence, uncertainty

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17773 Optimal MRO Process Scheduling with Rotable Inventory to Minimize Total Earliness

Authors: Murat Erkoc, Kadir Ertogral

Abstract:

Maintenance, repair and overhauling (MRO) of high cost equipment used in many industries such as transportation, military and construction are typically subject to regulations set by local governments or international agencies. Aircrafts are prime examples for this kind of equipment. Such equipment must be overhauled at certain intervals for continuing permission of use. As such, the overhaul must be completed by strict deadlines, which often times cannot be exceeded. Due to the fact that the overhaul is typically a long process, MRO companies carry so called rotable inventory for exchange of expensive modules in the overhaul process of the equipment so that the equipment continue its services with minimal interruption. The extracted module is overhauled and returned back to the inventory for future exchange, hence the name rotable inventory. However, since the rotable inventory and overhaul capacity are limited, it may be necessary to carry out some of the exchanges earlier than their deadlines in order to produce a feasible overhaul schedule. An early exchange results with a decrease in the equipment’s cycle time in between overhauls and as such, is not desired by the equipment operators. This study introduces an integer programming model for the optimal overhaul and exchange scheduling. We assume that there is certain number of rotables at hand at the beginning of the planning horizon for a single type module and there are multiple demands with known deadlines for the exchange of the modules. We consider an MRO system with identical parallel processing lines. The model minimizes total earliness by generating optimal overhaul start times for rotables on parallel processing lines and exchange timetables for orders. We develop a fast exact solution algorithm for the model. The algorithm employs full-delay scheduling approach with backward allocation and can easily be used for overhaul scheduling problems in various MRO settings with modular rotable items. The proposed procedure is demonstrated by a case study from the aerospace industry.

Keywords: rotable inventory, full-delay scheduling, maintenance, overhaul, total earliness

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17772 A Case Study of Determining the Times of Overhauls and the Number of Spare Parts for Repairable Items in Rolling Stocks with Simulation

Authors: Ji Young Lee, Jong Woon Kim

Abstract:

It is essential to secure high availability of railway vehicles to realize high quality and efficiency of railway service. Once the availability decreased, planned railway service could not be provided or more cars need to be reserved. additional cars need to be purchased or the frequency of railway service could be decreased. Such situation would be a big loss in terms of quality and cost related to railway service. Therefore, we make various efforts to get high availability of railway vehicles. Because it is a big loss to operators, we make various efforts to get high availability of railway vehicles. To secure high availability, the idle time of the vehicle needs to be reduced and the following methods are applied to railway vehicles. First, through modularization design, exchange time for line replaceable units is reduced which makes railway vehicles could be put into the service quickly. Second, to reduce periodic preventive maintenance time, preventive maintenance with short period would be proceeded test oriented to minimize the maintenance time, and reliability is secured through overhauls for each main component. With such design changes for railway vehicles, modularized components are exchanged first at the time of vehicle failure or overhaul so that vehicles could be put into the service quickly and exchanged components are repaired or overhauled. Therefore, spare components are required for any future failures or overhauls. And, as components are modularized and costs for components are high, it is considerably important to get reasonable quantities of spare components. Especially, when a number of railway vehicles were put into the service simultaneously, the time of overhauls come almost at the same time. Thus, for some vehicles, components need to be exchanged and overhauled before appointed overhaul period so that these components could be secured as spare parts for the next vehicle’s component overhaul. For this reason, components overhaul time and spare parts quantities should be decided at the same time. This study deals with the time of overhauls for repairable components of railway vehicles and the calculation of spare parts quantities in consideration of future failure/overhauls. However, as railway vehicles are used according to the service schedule, maintenance work cannot be proceeded after the service was closed thus it is quite difficult to resolve this situation mathematically. In this study, Simulation software system is used in this study for analyzing the time of overhauls for repairable components of railway vehicles and the spare parts for the railway systems.

Keywords: overhaul time, rolling stocks, simulation, spare parts

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17771 Prioritization in a Maintenance, Repair and Overhaul (MRO) System Based on Fuzzy Logic at Iran Khodro (IKCO)

Authors: Izadi Banafsheh, Sedaghat Reza

Abstract:

Maintenance, Repair, and Overhaul (MRO) of machinery are a key recent issue concerning the automotive industry. It has always been a debated question what order or priority should be adopted for the MRO of machinery. This study attempts to examine several criteria including process sensitivity, average time between machine failures, average duration of repair, availability of parts, availability of maintenance personnel and workload through a literature review and experts survey so as to determine the condition of the machine. According to the mentioned criteria, the machinery were ranked in four modes below: A) Need for inspection, B) Need for minor repair, C) Need for part replacement, and D) Need for major repair. The Fuzzy AHP was employed to determine the weighting of criteria. At the end, the obtained weights were ranked through the AHP for each criterion, three groups were specified: shaving machines, assembly and painting in four modes. The statistical population comprises the elite in the Iranian automotive industry at IKCO covering operation managers, CEOs and maintenance professionals who are highly specialized in MRO and perfectly knowledgeable in how the machinery function. The information required for this study were collected from both desk research and field review, which eventually led to construction of a questionnaire handed out to the sample respondents in order to collect information on the subject matter. The results of the AHP for weighting the criteria revealed that the availability of maintenance personnel was the top priority at coefficient of 0.206, while the process sensitivity took the last priority at coefficient of 0.066. Furthermore, the results of TOPSIS for prioritizing the IKCO machinery suggested that at the mode where there is need for inspection, the assembly machines took the top priority while paining machines took the third priority. As for the mode where there is need for minor repairs, the assembly machines took the top priority while the third priority belonged to the shaving machines. As for the mode where there is need for parts replacement, the assembly machines took the top priority while the third belonged to the paining machinery. Finally, as for the mode where there is need for major repair, the assembly machines took the top priority while the third belonged to the paining machinery.

Keywords: maintenance, repair, overhaul, MRO, prioritization of machinery, fuzzy logic, AHP, TOPSIS

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17770 Mathematical Modelling for Diesel Consumption of Articulated Vehicle Used in Oyo State, Nigeria

Authors: Ganiyu Samson Okunlola, Ladanu Abiodun Ajala, Olaide Oluwaseun Adegbayo

Abstract:

Since the usefulness of articulated vehicles is becoming more apparent and the diesel consumption of these vehicles constitutes a major portion of operating costs, development of mathematical model for their diesel consumption is of a great importance. Therefore, the present work developed a quantitative relationship between diesel consumption and vehicle age, annual use and cost of maintenance of the different makes of articulated vehicles. The vehicles selected for the study were FIAT 682 T3, IVECO 19036 and M.A.N. Diesel 19.240. The operating parameters for 90 vehicles of different age groups were recorded. Multiple regression models for diesel consumption of articulated vehicles of different makes were developed. From the analysis of results, it can be concluded that as the age of the vehicles increases, the diesel consumption increases. Also, as the diesel consumption increases, the cost of maintenance increases and there is a subsequent decrease in annual use. Moreover, FIAT 682 T3 and IVECO 19036 should be replaced at 7 years of age while M.A.N diesel should be replaced at 8 years of age. These are the ages where the diesel consumption becomes abnormal and uneconomical and they are points of optimal overhaul.

Keywords: vehicle, overhaul, age, uneconomical, diesel, consumption

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17769 Open Innovation Strategy (OIS) Paradigm and an OIS Capabilities Model

Authors: Anastasis D. Petrou

Abstract:

Innovation and strategy discussions do highlight open innovation as a new paradigm in business. Yet, a number of stumbling blocks in the form of closed innovation principles weaved into the fabric of a traditional business model stand in the way of the new paradigm’s momentum to increase value in various business contexts. The paper argues that businesses considering an engagement with the open innovation paradigm would need to take steps to improve their multiplicative, absorptive and relational capabilities, respectively. The needed improvements would amount to a business model evolutionary transformation and eventually bring about a paradigm overhaul in business. The transformation is worth staging over time to ensure that open innovation is developed across interconnected and partnered areas of strategic importance. This article develops an open innovation strategy (OIS) capabilities model, and employs examples from different industries to briefly discuss OIS’s potential to augment business value in a number of suggested areas for future research.

Keywords: close innovation, open innovation paradigm, open innovation strategy (OIS) paradigm, OIS capabilities model, multiplicative capability, absorptive capability, relational capability

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17768 Structural Challenges, the Forgotten Elephant in the Quest of Access to Justice: The Case of the South African Labour and Labour Appeal Courts

Authors: Carlos Joel Tchawouo Mbiada

Abstract:

This paper intends to refrain from debating the different meanings of justice, such as its social or moral meaning, nor to discuss the different theories of justice. This paper focuses on the legal understanding of access to justice to mean access to the court. Using the Labour and Labour Appeal Courts as a case study, this paper investigates whether the composition of the bench, the personnel and state mechanisms to promote access to court offer ideal conditions to access to court. The investigation is benchmarked against the South African new constitutional order underpinned by the concept of social justice to eradicate past injustices. To provide justice to all, the Constitution of the Republic of South Africa 1996 guarantees the right to access to the court. The question that takes centre stage in this paper is whether litigants are denied the right to access the Labour and Labour Appeal Courts. The paper argues that factors such as the status of the Labour and Labour Appeal Courts, the number of judges, and the building structure prevent litigants from accessing these courts. The paper advocates for a legislative overhaul of the Labour and Labour Appeal Courts structure so that litigants may access the courts. Until such time, the paper argues that the right to access the Labour and Labour Appeal Courts would remain far from the reach of many litigants.

Keywords: access to justice, access to court, labour court, labour appeal court

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17767 Minimizing Unscheduled Maintenance from an Aircraft and Rolling Stock Maintenance Perspective: Preventive Maintenance Model

Authors: Adel A. Ghobbar, Varun Raman

Abstract:

The Corrective maintenance of components and systems is a problem plaguing almost every industry in the world today. Train operators’ and the maintenance repair and overhaul subsidiary of the Dutch railway company is also facing this problem. A considerable portion of the maintenance activities carried out by the company are unscheduled. This, in turn, severely stresses and stretches the workforce and resources available. One possible solution is to have a robust preventive maintenance plan. The other possible solution is to plan maintenance based on real-time data obtained from sensor-based ‘Health and Usage Monitoring Systems.’ The former has been investigated in this paper. The preventive maintenance model developed for train operator will subsequently be extended, to tackle the unscheduled maintenance problem also affecting the aerospace industry. The extension of the model to the aerospace sector will be dealt with in the second part of the research, and it would, in turn, validate the soundness of the model developed. Thus, there are distinct areas that will be addressed in this paper, including the mathematical modelling of preventive maintenance and optimization based on cost and system availability. The results of this research will help an organization to choose the right maintenance strategy, allowing it to save considerable sums of money as opposed to overspending under the guise of maintaining high asset availability. The concept of delay time modelling was used to address the practical problem of unscheduled maintenance in this paper. The delay time modelling can be used to help with support planning for a given asset. The model was run using MATLAB, and the results are shown that the ideal inspection intervals computed using the extended from a minimal cost perspective were 29 days, and from a minimum downtime, perspective was 14 days. Risk matrix integration was constructed to represent the risk in terms of the probability of a fault leading to breakdown maintenance and its consequences in terms of maintenance cost. Thus, the choice of an optimal inspection interval of 29 days, resulted in a cost of approximately 50 Euros and the corresponding value of b(T) was 0.011. These values ensure that the risk associated with component X being maintained at an inspection interval of 29 days is more than acceptable. Thus, a switch in maintenance frequency from 90 days to 29 days would be optimal from the point of view of cost, downtime and risk.

Keywords: delay time modelling, unscheduled maintenance, reliability, maintainability, availability

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17766 Execution Time Optimization of Workflow Network with Activity Lead-Time

Authors: Xiaoping Qiu, Binci You, Yue Hu

Abstract:

The executive time of the workflow network has an important effect on the efficiency of the business process. In this paper, the activity executive time is divided into the service time and the waiting time, then the lead time can be extracted from the waiting time. The executive time formulas of the three basic structures in the workflow network are deduced based on the activity lead time. Taken the process of e-commerce logistics as an example, insert appropriate lead time for key activities by using Petri net, and the executive time optimization model is built to minimize the waiting time with the time-cost constraints. Then the solution program-using VC++6.0 is compiled to get the optimal solution, which reduces the waiting time of key activities in the workflow, and verifies the role of lead time in the timeliness of e-commerce logistics.

Keywords: electronic business, execution time, lead time, optimization model, petri net, time workflow network

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17765 Integrated Gas Turbine Performance Diagnostics and Condition Monitoring Using Adaptive GPA

Authors: Yi-Guang Li, Suresh Sampath

Abstract:

Gas turbine performance degrades over time, and the degradation is greatly affected by environmental, ambient, and operating conditions. The engines may degrade slowly under favorable conditions and result in a waste of engine life if a scheduled maintenance scheme is followed. They may also degrade fast and fail before a scheduled overhaul if the conditions are unfavorable, resulting in serious secondary damage, loss of engine availability, and increased maintenance costs. To overcome these problems, gas turbine owners are gradually moving from scheduled maintenance to condition-based maintenance, where condition monitoring is one of the key supporting technologies. This paper presents an integrated adaptive GPA diagnostics and performance monitoring system developed at Cranfield University for gas turbine gas path condition monitoring. It has the capability to predict the performance degradation of major gas path components of gas turbine engines, such as compressors, combustors, and turbines, using gas path measurement data. It is also able to predict engine key performance parameters for condition monitoring, such as turbine entry temperature that cannot be directly measured. The developed technology has been implemented into digital twin computer Software, Pythia, to support the condition monitoring of gas turbine engines. The capabilities of the integrated GPA condition monitoring system are demonstrated in three test cases using a model gas turbine engine similar to the GE aero-derivative LM2500 engine widely used in power generation and marine propulsion. It shows that when the compressor of the model engine degrades, the Adaptive GPA is able to predict the degradation and the changing engine performance accurately using gas path measurements. Such a presented technology and software are generic, can be applied to different types of gas turbine engines, and provide crucial engine health and performance parameters to support condition monitoring and condition-based maintenance.

Keywords: gas turbine, adaptive GPA, performance, diagnostics, condition monitoring

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17764 Diagnostic of Breakdown in High Voltage Bushing Power Transformer 500 kV Cirata Substation

Authors: Andika Bagaskara, Andhika Rizki Pratama, Lalu Arya Repatmaja, Septhian Ditaputra Raharja

Abstract:

The power transformer is one of the critical things in system transmission. Regular testing of the power transformer is very important to maintain the reliability of the power. One of the causes of the failure of the transformer is the breakdown of insulation caused by the presence of voids in the equipment that is electrified. As a result of the voids that occur in this power transformer equipment, it can cause partial discharge. Several methods were used to determine the occurrence of damage to the power transformer equipment, such as Sweep Frequency Response Analysis (SFRA) and Tan Delta. In Inter Bus Transformer (IBT) 500/150 kV Cirata Extra High Voltage (EHV) Substation, a breakdown occurred in the T-phase tertiary bushing. From the lessons learned in this case, a complete electrical test was carried out. From the results of the complete electrical test, there was a suspicion of deterioration in the post-breakdown SFRA results. After overhaul and inspection, traces of voids were found on the tertiary bushing, which indicated a breakdown in the tertiary bushing of the IBT 500/150kV Cirata Substation transformer.

Keywords: void, bushing, SFRA, Tan Delta

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17763 The Words of the Pandemic in Spillover by David Quammen

Authors: Anna Maria Re

Abstract:

Taking advantage of the ecolinguistic theoretical and practical analysis, the work intends the prophetic, punctual, and at times disturbing language used by David Quammen in Spillover, questioning it from an ecological perspective and contributing to the search for new stories. In the famous volume, the author illustrates a literary history of the great epidemics and pandemics, demonstrating that viruses are nature's inevitable response to man's assault on ecosystems. In doing so, he introduces new words, which have tamed our anxieties in recent years since writing as a human artistic expression can mirror the human conscience. Writing in the Anthropocene, coining a new reference lexicon with respect to what is happening, means offering a form to the idea of survival of the planet, imagining the human being grappling with an environment whose conformation he himself has helped to change with a language that is no longer effective in describing the world as we have known it and that quickly needs a radical overhaul. Following the methodology proposed in Ecolinguistics: language, ecology and the stories we live by, the analysis in the paper will enhance the language that encodes new stories based on: ideologies, framings, metaphors, evaluations, identities, convictions, and salience.

Keywords: Anthropocene, pandemic, spillover, virus, zoonosis

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17762 The Political Pedagogy of Everyday Life in the French Revolution

Authors: Michael Ruiz

Abstract:

Many scholars view the French Revolution as the origins of ‘modern nationalism,’ citing the unprecedented rhetorical power of ‘the nation’ and the emergence of a centralized, modern nation-state during this time. They have also stressed the role of public education in promoting a national language and creating a sense of shared national identity among the masses. Yet as many cultural historians have shown, revolutionary leaders undertook an unprecedented campaign to overhaul French culture in the 1790s in order to cultivate these national ideals and inspire Republican virtues, in what has been called ‘political pedagogy.’ In contrast to scholars of nationalism, who emphasize formal education, revolutionaries attempted to translate abstract ideas of equality and liberty into palpable representations that would inundate everyday life, thereby serving as pedagogical tools. Material culture and everyday life became state apparatuses not just for winning over citizens’ hearts and minds, but for influencing the very formation of the citizen and their innermost ‘self.’ This paper argues that nationalism began in 1789, when ‘the self’ became a political concern and its formation a state project for cultivating political legitimacy. By broadening the meaning of ‘political pedagogy,’ this study brings together scholarship on nationalism with cultural history, thereby highlighting nations and nationalism as banal, palpable, quotidian phenomena and historicizing the complex emergence of ‘modern nationalism.’ Moreover, because the contemporary view of material culture and pedagogy was highly gendered, this study shows the role of culture in the development of a homosocial, male-dominated public sphere in the 19th century. The legacy of the French Revolution’s concern with culture thus persists as much in our vocabulary for political expression as it does in the material world, remaining deeply embedded in everyday day life as a crucial, nearly-invisible, component of nationalism.

Keywords: French Revolution, nationalism, political culture, material culture

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17761 Pakistan’s Taxation System: A Critical Appraisal

Authors: Khalid Javed, Rashid Mahmood

Abstract:

The constitution empowers the Federal Government to collect taxes on income other than agricultural income, taxes on capital value, customs, excise duties and sales taxes. The Central Board of Revenue (CBR) and its subordinate departments administer the tax system. Each of the three principal taxes has a different history and different set of issues. For a large number of income tax payers the core of the business process is pre-audit and assessment by a tax official. This process gives considerable discretion to tax officials, with potential for abuse. Moreover, this process is also not tenable as the number of taxpayers increase. The report is focused on a total overhaul of the process and organization of income tax. Sales tax is recent and its process and organization is adjusted to the needs of an expanding tax base. These are based on self-assessment and selective audit. Similarly, in customs the accent is on accelerating and broadening the changes begun in recent years. Before long, central excise will be subsumed in sales tax. During the nineties, despite many changes in the tax regime and introduction of withholding and presumptive taxes, Federal Government tax to GDP ratio has varied narrowly around eleven percent. The tax base has grown but still remains narrow and skewed. The number of income tax filers is around one million.

Keywords: central board of revenue, GDP, sale tax, income tax

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17760 Dynamic Simulation for Surface Wear Prognosis of the Main Bearings in the Internal Combustion Engine

Authors: Yanyan Zhang, Ziyu Diao, Zhentao Liu, Ruidong Yan

Abstract:

The wear character of the main bearing is one of the critical indicators for the overhaul of an internal combustion engine, and the aim of this paper is to reveal the dynamic wear mechanism of the main bearings. A numerical simulation model combined multi-body dynamic equations of the engine, the average Reynolds equations of the bearing lubricant, asperity contact and wear model of the joint surfaces were established under typical operating conditions. The wear results were verified by experimental data, and then the influence of operating conditions, bearing clearance and cylinder pressure on the wear character of selected main bearings were analyzed. The results show that the contribution degree of different working conditions on the wear profile and depth of each bearing is obviously different, and the increase of joint clearance or cylinder pressure will accelerate the wear. The numerical model presented can be used to wear prognosis for joints and provide guidance for optimization design of sliding bearings.

Keywords: dynamic simulation, multi-body dynamics, sliding bearing, surface wear

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17759 Memory, Self, and Time: A Bachelardian Perspective

Authors: Michael Granado

Abstract:

The French philosopher Gaston Bachelard’s philosophy of time is articulated in his two works on the subject, the Intuition of the Instant (1932) and his The Dialectic of Duration (1936). Both works present a systematic methodology predicated upon the assumption that our understanding of time has radically changed as a result of Einstein and subsequently needs to be reimagined. Bachelard makes a major distinction in his discussion of time: 1. Time as it is (physical time), 2. Time as we experience it (phenomenological time). This paper will focus on the second distinction, phenomenological time, and explore the connections between Bachelard’s work and contemporary psychology. Several aspects of Bachelard’s philosophy of time nicely complement our current understanding of memory and self and clarify how the self relates to experienced time. Two points, in particular, stand out; the first is the relative nature of subjective time, and the second is the implications of subjective time in the formation of the narrative self. Bachelard introduces two philosophical concepts to explain these points: rhythmanalysis and reverie. By exploring these concepts, it will become apparent that there is an undeniable link between memory, self, and time. Through the use of narrative self, the individual connects and links memories and time together to form a sense of personal identity.

Keywords: Gaston Bachelard, memory, self, time

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17758 Phase Optimized Ternary Alloy Material for Gas Turbines

Authors: Mayandi Ramanathan

Abstract:

Gas turbine blades see the most aggressive thermal stress conditions within the engine, due to Turbine Entry Temperatures in the range of 1500 to 1600°C, but in synchronization with other functional components, they must readily deliver efficient performance, whilst incurring minimal overhaul and repair costs during its service life up to 5 million flying miles. The blades rotate at very high rotation rates and remove significant amount of thermal power from the gas stream. At high temperatures the major component failure mechanism is creep. During its service over time under high temperatures and loads, the blade will deform, lengthen and rupture. High strength and stiffness in the longitudinal direction up to elevated service temperatures are certainly the most needed properties of turbine blades. The proposed advanced Ti alloy material needs a process that provides strategic orientation of metallic ordering, uniformity in composition and high metallic strength. 25% Ta/(Al+Ta) ratio ensures TaAl3 phase formation, where as 51% Al/(Al+Ti) ratio ensures formation of α-Ti3Al and γ-TiAl mixed phases fand the three phase combination ensures minimal Al excess (~1.4% Al excess), unlike Ti-47Al-2Cr-2Nb which has significant excess Al (~5% Al excess) that could affect the service life of turbine blades. This presentation will involve the summary of additive manufacturing and heat treatment process conditions to fabricate turbine blade with Ti-43Al matrix alloyed with optimized amount of refractory Ta metal. Summary of thermo-mechanical test results such as high temperature tensile strength, creep strain rate, thermal expansion coefficient and fracture toughness will be presented. Improvement in service temperature of the turbine blades and corrosion resistance dependence on coercivity of the alloy material will be reported. Phase compositions will be quantified, and a summary of its correlation with creep strain rate will be presented.

Keywords: gas turbine, aerospace, specific strength, creep, high temperature materials, alloys, phase optimization

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17757 A Simulation-Optimization Approach to Control Production, Subcontracting and Maintenance Decisions for a Deteriorating Production System

Authors: Héctor Rivera-Gómez, Eva Selene Hernández-Gress, Oscar Montaño-Arango, Jose Ramon Corona-Armenta

Abstract:

This research studies the joint production, maintenance and subcontracting control policy for an unreliable deteriorating manufacturing system. Production activities are controlled by a derivation of the Hedging Point Policy, and given that the system is subject to deterioration, it reduces progressively its capacity to satisfy product demand. Multiple deterioration effects are considered, reflected mainly in the quality of the parts produced and the reliability of the machine. Subcontracting is available as support to satisfy product demand; also overhaul maintenance can be conducted to reduce the effects of deterioration. The main objective of the research is to determine simultaneously the production, maintenance and subcontracting rate which minimize the total incurred cost. A stochastic dynamic programming model is developed and solved through a simulation-based approach composed of statistical analysis and optimization with the response surface methodology. The obtained results highlight the strong interactions between production, deterioration and quality which justify the development of an integrated model. A numerical example and a sensitivity analysis are presented to validate our results.

Keywords: subcontracting, optimal control, deterioration, simulation, production planning

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17756 A Hazard Rate Function for the Time of Ruin

Authors: Sule Sahin, Basak Bulut Karageyik

Abstract:

This paper introduces a hazard rate function for the time of ruin to calculate the conditional probability of ruin for very small intervals. We call this function the force of ruin (FoR). We obtain the expected time of ruin and conditional expected time of ruin from the exact finite time ruin probability with exponential claim amounts. Then we introduce the FoR which gives the conditional probability of ruin and the condition is that ruin has not occurred at time t. We analyse the behavior of the FoR function for different initial surpluses over a specific time interval. We also obtain FoR under the excess of loss reinsurance arrangement and examine the effect of reinsurance on the FoR.

Keywords: conditional time of ruin, finite time ruin probability, force of ruin, reinsurance

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17755 Communication Policies of Turkey Related to European Union

Authors: Muhammet Erbay

Abstract:

The phenomenon of communication that has been studied by different disciplines has social, political and economical aspects. The scope of communication has extended from a traditional content to the modern world which is under the control of mass media. Nowadays, thanks to globalization and technological facilities, many companies, public or international institutions take advantage of new communication technologies and overhaul their policies. European Union (EU) is one of the effective institutions in this sphere. It aims to harmonize the communication infrastructure and policies of member countries which have gone through the process of political unification. It is a significant problem for the unification of EU to have legal restrictions or critical differences in communication facilities among countries while technology stands at the center of economic and social life. Therefore, EU institutions place a particular importance to their communication policies. Besides, communication processes have a vital importance in creating a European public opinion in the process of political integration. Based on the evaluation above, the aim of this paper is to analyze the cohesion process of Turkey that tries to take an active role in EU communication policies and has on-going negotiations. This article does not only confine itself to the technical details of communication policies but also aims to evaluate socio-political dimension of the process. Therefore, a corporate review has been featured in the study and Turkey's compliance process in communication policies on European Union has been evaluated by the means of deduction method. Some problematic areas have been identified in compliance process on communication policies such as human rights and minority rights, whereas compliance process on communication infrastructure and technology proceeds effectively.

Keywords: communication policies, European Union, integration, Turkey

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17754 Evaluation of Reliability Indices Using Monte Carlo Simulation Accounting Time to Switch

Authors: Sajjad Asefi, Hossein Afrakhte

Abstract:

This paper presents the evaluation of reliability indices of an electrical distribution system using Monte Carlo simulation technique accounting Time To Switch (TTS) for each section. In this paper, the distribution system has been assumed by accounting random repair time omission. For simplicity, we have assumed the reliability analysis to be based on exponential law. Each segment has a specified rate of failure (λ) and repair time (r) which will give us the mean up time and mean down time of each section in distribution system. After calculating the modified mean up time (MUT) in years, mean down time (MDT) in hours and unavailability (U) in h/year, TTS have been added to the time which the system is not available, i.e. MDT. In this paper, we have assumed the TTS to be a random variable with Log-Normal distribution.

Keywords: distribution system, Monte Carlo simulation, reliability, repair time, time to switch (TTS)

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17753 Temporal Axis in Japanese: The Paradox of a Metaphorical Orientation in Time

Authors: Tomoko Usui

Abstract:

In the field of linguistics, it has been said that concepts associated with space and motion systematically contribute structure to the temporal concept. This is the conceptual metaphor theory. conceptual metaphors typically employ a more abstract concept (time) as their target and a more concrete or physical concept as their source (space). This paper will examine two major temporal conceptual metaphors: Ego-centered Moving Time Metaphor and Time-RP Metaphor. Moving time generally receives a front-back orientation, however, Japanese shows a different orientation given to time. By means of Ego perspective, this paper will illustrate the paradox of a metaphorical orientation in time.

Keywords: Ego-centered Moving Time Metaphor, Japanese saki, temporal metaphors, Time RP Metaphor

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17752 The Nigeria Police Force: Human Resources Management Issues and the Community Policing Policy Transfer

Authors: Aminu Musa Audu

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This paper examines the human resources management issues of the Nigeria Police and how it is impacting the community policing policy transfer. Nigeria Police Force is the organisation in the country with the constitutional responsibility of maintaining law and order. The high level of crime and other forms of insecurity called for the introduction of ‘police-community partnership’ strategy in 2003. The trend of events has suggested that the effort is not yielding result, partly because the police in Nigeria are facing human resources management challenges. For instance, the prospective candidates for the police jobs are usually not vetted a situation which provides the possibility of recruiting persons of low academic background and questionable character, or even criminal records. Moreover, the existing training, development infrastructure and other logistics for the job of policing are not in good condition. Consequently, the implementation of the ‘community policing’ policy for crime prevention and control in Nigeria stands to suffer setbacks. Adopting qualitative methods and with focus groups discussions and individual in-depth interviews for data collections, the findings from the views and perspectives of the participants were suggestive of poor handlings of human resources management of the Nigeria police organisation and with negative effect on the implementation of community policing policy. The paper therefore recommends that a total overhaul of the human resources component of the police organisation is necessary in the community policing policy transfer process for crime prevention and control in Nigeria.

Keywords: Nigeria Police Force, community policing policy transfer, human resources management, police-community partnership

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17751 Manipulative Figurative Linguistic Violence of Contemporary National Anthems: A Socio-Cognitive Critical Discourse Analysis

Authors: Samson Olasunkanmi Oluga, Teh Chee Send, Gerard Sagaya Raj Rajo

Abstract:

It is ironical that the national anthems of many nations that are in the forefront of the global condemnation of violence of all forms have portions or expressions that propagate various forms of linguistic violence which advocate attacking opponents, going to war, shedding blood and sacrificing lives. These diametrically contradict contemporary yearnings for global tranquility and the ideals of the United Nations established for the maintenance of international peace and harmony aimed at making the world a safe haven for all and sundry. The linguistic violence of many national anthems is manipulatively constructed /presented via the instrumentality of the figurative or rhetorical language. This helps to linguistically embellish the violent ideas communicated and makes them sound somehow better or logical to the target audience with the intention of cognitively manipulating them to accept or rationalize such violent ideas. This paper, therefore, presents the outcome of a linguistic exploration/examination of national anthems which reveals elements or cases manipulative figurative linguistic violence in the anthems of twenty-one (21) nations. The paper details a Socio-Cognitive Critical Discourse Analysis of the manipulative figures of comparison, contrast, indirectness, association and sound used to convey the linguistic violence of the identified national anthems. Finally, the paper advocates the need for linguistic overhaul of affected anthems so that the language of anthems which epitomize nations can be pacific and in tandem with contemporary global trends.

Keywords: national anthems, linguistic violence, figurative language, cognitive, manipulation, CDA

Procedia PDF Downloads 308
17750 A Distinct Approach Towards Relativity and Time Dilation

Authors: Vipin Choudhary

Abstract:

Time Dilation is the difference in the amount of time two clocks measure in the same inertial frame. Many studies have explored the relativity of time dilation using various approaches. However, the scientific and mathematical explanation of time dilation of moving things and light pulse clocks still has limited research. Therefore, this article examines relativity by utilizing scientific and mathematical approaches; the experience of moving things and light pulse clock ticks have been examined. The study revealed that the time elapsed for the same process is different for the different observers. Here, it showed that the time can be expressed in the form of a wave. In addition, the relative distance changes between the observers, and the observing subject time flows differently for the observer relative to the observing subject.

Keywords: Einstein's special theory of relativity, reference frame, time dilation, length contraction, Lorentz transformation.

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17749 Unification of Indonesia Time Zones Encourages People to Be on Time for Facing ASEAN Economic Community

Authors: Hasrullah Hasrullah

Abstract:

Since December 2015, the ASEAN Economic Community (AEC) is officially declared in the 27th Summit Conference of ASEAN and Indonesia is one of country are listed in the ASEAN members. Per January 1st, 2016 the ASEAN Economic Community (AEC) came into effect. However, its implementation in Indonesia is still weighing the pros and cons because Indonesia is considered too late to prepare for the ASEAN Economic Community (AEC). In other words, rubber time of Indonesian people has been occurring in the AEC. This paper reviews how Indonesia language influences people’s attitude to be rubber time culture and how time zones of Indonesia influence people’s attitude through media on television to be rubber time culture. The author addresses this research question empirically by collecting data from various sources of data those are relevant and compare among the unification of Indonesia time zones. The result demonstrates that unification of Indonesia time zones to be Standard Indonesia Time is a solution to encourage people to be ready on time for facing ASEAN Economic Community (AEC).

Keywords: unification time zones, Indonesia Language, Rubber Time, AEC

Procedia PDF Downloads 341
17748 A Cosmic Time Dilation Model for the Week of Creation

Authors: Kwok W. Cheung

Abstract:

A scientific interpretation of creation reconciling the beliefs of six literal days of creation and a 13.7-billion-year-old universe currently perceived by most modern cosmologists is proposed. We hypothesize that the reference timeframe of God’s creation is associated with some cosmic time different from the earth's time. We show that the scale factor of earth time to cosmic time can be determined by the solution of the Friedmann equations. Based on this scale factor and some basic assumptions, we derive a Cosmic Time Dilation model that harmonizes the literal meaning of creation days and scientific discoveries with remarkable accuracy.

Keywords: cosmological expansion, time dilation, creation, genesis, relativity, Big Bang, biblical hermeneutics

Procedia PDF Downloads 53
17747 Exclusive Value Adding by iCenter Analytics on Transient Condition

Authors: Zhu Weimin, Allegorico Carmine, Ruggiero Gionata

Abstract:

During decades of Baker Hughes (BH) iCenter experience, it is demonstrated that in addition to conventional insights on equipment steady operation conditions, insights on transient conditions can add significant and exclusive value for anomaly detection, downtime saving, and predictive maintenance. Our work shows examples from the BH iCenter experience to introduce the advantages and features of using transient condition analytics: (i) Operation under critical engine conditions: e.g., high level or high change rate of temperature, pressure, flow, vibration, etc., that would not be reachable in normal operation, (ii) Management of dedicated sub-systems or components, many of which are often bottlenecks for reliability and maintenance, (iii) Indirect detection of anomalies in the absence of instrumentation, (iv) Repetitive sequences: if data is properly processed, the engineering features of transients provide not only anomaly detection but also problem characterization and prognostic indicators for predictive maintenance, (v) Engine variables accounting for fatigue analysis. iCenter has been developing and deploying a series of analytics based on transient conditions. They are contributing to exclusive value adding in the following areas: (i) Reliability improvement, (ii) Startup reliability improvement, (iii) Predictive maintenance, (iv) Repair/overhaul cost down. Illustrative examples for each of the above areas are presented in our study, focusing on challenges and adopted techniques ranging from purely statistical approaches to the implementation of machine learning algorithms. The obtained results demonstrate how the value is obtained using transient condition analytics in the BH iCenter experience.

Keywords: analytics, diagnostics, monitoring, turbomachinery

Procedia PDF Downloads 56
17746 Simulation of Pedestrian Service Time at Different Delay Times

Authors: Imran Badshah

Abstract:

Pedestrian service time reflects the performance of the facility, and it’s a key parameter to analyze the capability of facilities provided to serve pedestrians. The level of service of pedestrians (LOS) mainly depends on pedestrian time and safety. The pedestrian time utilized by taking a service is mainly influenced by the number of available services and the time utilized by each pedestrian in receiving a service; that is called a delay time. In this paper, we analyzed the simulated pedestrian service time with different delay times. A simulation is performed in AnyLogic by developing a model that reflects the real scenario of pedestrian services such as ticket machine gates at rail stations, airports, shopping malls, and cinema halls. The simulated pedestrian time is determined for various delay values. The simulated result shows how pedestrian time changes with the delay pattern. The histogram and time plot graph of a model gives the mean, maximum and minimum values of the pedestrian time. This study helps us to check the behavior of pedestrian time at various services such as subway stations, airports, shopping malls, and cinema halls.

Keywords: agent-based simulation, anylogic model, pedestrian behavior, time delay

Procedia PDF Downloads 191
17745 Discrete-Time Bulk Queue with Service Capacity Depending on Previous Service Time

Authors: Yutae Lee

Abstract:

This paper considers a discrete-time bulk-arrival bulkservice queueing system, where service capacity varies depending on the previous service time. By using the generating function technique and the supplementary variable method, we compute the distributions of the queue length at an arbitrary slot boundary and a departure time.

Keywords: discrete-time queue, bulk queue, variable service capacity, queue length distribution

Procedia PDF Downloads 459