Search results for: maintenance scheme
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2858

Search results for: maintenance scheme

2858 A Hybrid P2P Storage Scheme Based on Erasure Coding and Replication

Authors: Usman Mahmood, Khawaja M. U. Suleman

Abstract:

A peer-to-peer storage system has challenges like; peer availability, data protection, churn rate. To address these challenges different redundancy, replacement and repair schemes are used. This paper presents a hybrid scheme of redundancy using replication and erasure coding. We calculate and compare the storage, access, and maintenance costs of our proposed scheme with existing redundancy schemes. For realistic behaviour of peers a trace of live peer-to-peer system is used. The effect of different replication, and repair schemes are also shown. The proposed hybrid scheme performs better than existing double coding hybrid scheme in all metrics and have an improved maintenance cost than hierarchical codes.

Keywords: erasure coding, P2P, redundancy, replication

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2857 Advanced CoMP Scheme for LTE-based V2X System

Authors: Su-Hyun Jung, Young-Su Ryu, Yong-Jun Kim, Hyoung-Kyu Song

Abstract:

In this paper, a highly efficient coordinated multiple-point (CoMP) scheme for vehicular communication is proposed. The proposed scheme controls the transmit power and applies proper transmission scheme for the various situations. The proposed CoMP scheme provides comparable performance to the conventional dynamic cell selection (DCS) scheme. Moreover, this scheme provides improved power efficiency compared with the conventional joint transmission (JT) scheme. Simulation results show that the proposed scheme can achieve more enhanced performance with the high power efficiency and improve the cell capacity.

Keywords: CoMP, LTE-A, V2I, V2V, V2X.

Procedia PDF Downloads 583
2856 Generalization of Blom Key Predistribution Scheme

Authors: Abbas Cheraghi

Abstract:

A key predistribution scheme provides one method to distribute secret ahead of time. Blom’s scheme is a symmetric threshold key exchange protocol in cryptography. The scheme was proposed by the Swedish cryptographer Rolf Blom. In this kind of scheme, trusted authority gives each user a secret key and a public identifier, which enables any two users to create independently a shared key for communicating between each other. However, if an attacker can compromise the keys of at least Known numbers of users, he can break the scheme and reconstruct every shared key. In this paper generalized Blom’s Scheme by multivariate Lagrange interpolation formula. This scheme is a form of threshold secret sharing scheme. In this new scheme, the amount of information transmitted by the trusted authority is independent of the numbers of users. In addition, this scheme is unconditionally secure against any individual user.

Keywords: key predistribution, blom’s scheme, secret sharing, unconditional secure

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2855 Scheduled Maintenance and Downtime Cost in Aircraft Maintenance Management

Authors: Remzi Saltoglu, Nazmia Humaira, Gokhan Inalhan

Abstract:

During aircraft maintenance scheduling, operator calculates the budget of the maintenance. Usually, this calculation includes only the costs that are directly related to the maintenance process such as cost of labor, material, and equipment. In some cases, overhead cost is also included. However, in some of those, downtime cost is neglected claiming that grounding is a natural fact of maintenance; therefore, it is not considered as part of the analytical decision-making process. Based on the normalized data, we introduce downtime cost with its monetary value and add its seasonal character. We envision that the rest of the model, which works together with the downtime cost, could be checked with the real life cases, through the review of MRO cost and airline spending in the particular and scheduled maintenance events.

Keywords: aircraft maintenance, downtime, downtime cost, maintenance cost

Procedia PDF Downloads 353
2854 Planning Quality and Maintenance Activities in a Closed-Loop Serial Multi-Stage Manufacturing System under Constant Degradation

Authors: Amauri Josafat Gomez Aguilar, Jean Pierre Kenné

Abstract:

This research presents the development of a self-sustainable manufacturing system from a circular economy perspective, structured by a multi-stage serial production system consisting of a series of machines under deterioration in charge of producing a single product and a reverse remanufacturing system constituted by the same productive systems of the first scheme and different tooling, fed by-products collected at the end of their life cycle, and non-conforming elements of the first productive scheme. Since the advanced production manufacturing system is unable to satisfy the customer's quality expectations completely, we propose the development of a mixed integer linear mathematical model focused on the optimal search and assignment of quality stations and preventive maintenance operation to the machines over a time horizon, intending to segregate the correct number of non-conforming parts for reuse in the remanufacturing system and thereby minimizing production, quality, maintenance, and customer non-conformance penalties. Numerical experiments are performed to analyze the solutions found by the model under different scenarios. The results showed that the correct implementation of a closed manufacturing system and allocation of quality inspection and preventive maintenance operations generate better levels of customer satisfaction and an efficient manufacturing system.

Keywords: closed loop, mixed integer linear programming, preventive maintenance, quality inspection

Procedia PDF Downloads 85
2853 Appraisal of Maintenance Practices in Selected Tourist Attraction in Bauchi State, Nigeria

Authors: Eldah Ephraim Buba, Amina Bata Zoaka, Aishatu Ibrahim

Abstract:

This study appraised maintenance practices in selected tourist attractions in Bauchi state, Nigeria. Four tourist attractions were used for the research. Checklists were used to assess operations and repairs maintenance practices in the different attractions. The study carried out personal assessment thrice in six months without prior knowledge of the staff in charge for operational maintenance. Records of repairs maintenance from the attractions maintenance unit for a period of ten years were assessed using the checklists. The findings of the study show that operations maintenance was not adequately carried out in the four tourists attractions. Repairs maintenance was carried out in Yankari game reserve and safari, but repairs maintenance was poor in the other three attractions. The study therefore, recommends that adequate maintenance should be practiced in tourist attractions to expand the lifespan of the facilities and also encourage tourist patronage.

Keywords: appraisal, maintenance, practices, tourist attraction

Procedia PDF Downloads 300
2852 Neural Network Based Approach of Software Maintenance Prediction for Laboratory Information System

Authors: Vuk M. Popovic, Dunja D. Popovic

Abstract:

Software maintenance phase is started once a software project has been developed and delivered. After that, any modification to it corresponds to maintenance. Software maintenance involves modifications to keep a software project usable in a changed or a changing environment, to correct discovered faults, and modifications, and to improve performance or maintainability. Software maintenance and management of software maintenance are recognized as two most important and most expensive processes in a life of a software product. This research is basing the prediction of maintenance, on risks and time evaluation, and using them as data sets for working with neural networks. The aim of this paper is to provide support to project maintenance managers. They will be able to pass the issues planned for the next software-service-patch to the experts, for risk and working time evaluation, and afterward to put all data to neural networks in order to get software maintenance prediction. This process will lead to the more accurate prediction of the working hours needed for the software-service-patch, which will eventually lead to better planning of budget for the software maintenance projects.

Keywords: laboratory information system, maintenance engineering, neural networks, software maintenance, software maintenance costs

Procedia PDF Downloads 358
2851 Study on the Central Differencing Scheme with the Staggered Version (STG) for Solving the Hyperbolic Partial Differential Equations

Authors: Narumol Chintaganun

Abstract:

In this paper we present the second-order central differencing scheme with the staggered version (STG) for solving the advection equation and Burger's equation. This scheme based on staggered evolution of the re-constructed cell averages. This scheme results in the second-order central differencing scheme, an extension along the lines of the first-order central scheme of Lax-Friedrichs (LxF) scheme. All numerical simulations presented in this paper are obtained by finite difference method (FDM) and STG. Numerical results are shown that the STG gives very good results and higher accuracy.

Keywords: central differencing scheme, STG, advection equation, burgers equation

Procedia PDF Downloads 557
2850 Lean Philosophy towards the Enhancement of Maintenance Programs Efficiency with Particular Attention to Libyan Oil and Gas Scenario

Authors: Sulayman Adrees Mohammed, Ahmed Faraj Abd Alsameea

Abstract:

The ongoing hindrance for Libyan oil and gas companies is the persistent challenge of eradicating maintenance program failures that result in exorbitant costs and production setbacks. Accordingly, this research is prompted to introduce the concept of lean philosophy in maintenance, which aims to eliminate waste and enhance productivity in maintenance procedures through the identification and differentiation of value-adding (VA) and non-value-adding (NVA) activities. The purpose of this paper was to explore and describe the benefits that can be gained by adopting the Lean philosophy towards the enhancement of maintenance programs' efficiency from theoretical perspectives. The oil industry maintenance community in Libya now has an introduced tool by which they can effectively evaluate their maintenance program functionality and reduce the areas of non-value added activities within maintenance, thereby enhancing the availability of the equipment and the capacity of the oil and gas facilities.

Keywords: efficiency, lean philosophy, Libyan oil and gas scenario, maintenance programs

Procedia PDF Downloads 109
2849 Providing a Practical Model to Reduce Maintenance Costs: A Case Study in GeG Company

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

Abstract:

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

Keywords: GeG company, maintainability, maintenance costs, reliability-center-maintenance

Procedia PDF Downloads 221
2848 Adaptive Cooperative Scheme Considering the User Location

Authors: Bit-Na Kwon, Hyun-Jee Yang, Dong-Hyun Ha, Hyoung-Kyu Song

Abstract:

In this paper, an adaptive cooperative scheme in the cell edge is proposed. The proposed scheme considers the location of a user and applies the suitable cooperative scheme. In cellular systems, the performance of communication is degraded if the user is located in the cell edge. In conventional scheme, two base stations are used in order to obtain diversity gain. However, the performance of communication is not sufficiently improved since the distance between each base station and a user is still distant. Therefore, we propose a scheme that the relays are used and the cooperative scheme is adaptively applied according to the user location. Through simulation results, it is confirmed that the proposed scheme has better performance than the conventional scheme.

Keywords: adaptive transmission, cooperative communication, diversity gain, OFDM

Procedia PDF Downloads 572
2847 Aircraft Line Maintenance Equipped with Decision Support System

Authors: B. Sudarsan Baskar, S. Pooja Pragati, S. Raj Kumar

Abstract:

The cost effectiveness in aircraft maintenance is of high privilege in the recent days. The cost effectiveness can be effectively made when line maintenance activities are incorporated at airports during Turn around time (TAT). The present work outcomes the shortcomings that affect the dispatching of the aircrafts, aiming at high fleet operability and low maintenance cost. The operational and cost constraints have been discussed and a suggestive alternative mechanism is proposed. The possible allocation of all deferred maintenance tasks to a set of all deferred maintenance tasks to a set of suitable airport resources have termed as alternative and is discussed in this paper from the data’s collected from the kingfisher airlines.

Keywords: decision support system, aircraft maintenance planning, maintenance-cost, RUL(remaining useful life), logistics, supply chain management

Procedia PDF Downloads 502
2846 Providing a Practical Model to Reduce Maintenance Costs: A Case Study in Golgohar Company

Authors: Iman Atighi, Jalal Soleimannejad, Ahmad Akbarinasab, Saeid Moradpour

Abstract:

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

Keywords: Golgohar Iron Ore Mining and Industrial Company, maintainability, maintenance costs, reliability-center-maintenance

Procedia PDF Downloads 302
2845 Improved Performance Using Adaptive Pre-Coding in the Cellular Network

Authors: Yong-Jun Kim, Jae-Hyun Ro, Chang-Bin Ha, Hyoung-Kyu Song

Abstract:

This paper proposes the cooperative transmission scheme with pre-coding because the cellular communication requires high reliability. The cooperative transmission scheme uses pre-coding method with limited feedback information among small cells. Particularly, the proposed scheme has adaptive mode according to the position of mobile station. Thus, demand of recent wireless communication is resolved by this scheme. From the simulation results, the proposed scheme has better performance compared to the conventional scheme in the cellular network.

Keywords: CDD, cellular network, pre-coding, SPC

Procedia PDF Downloads 569
2844 Strategic Maintenance Management of Built Facilities in an Organisation

Authors: Anita D. Adamu, Winston M. W. Shakantu

Abstract:

Maintenance management is no longer a stand-alone activity. It has now assumed a strategic position in many organisations that have recognised its importance in achieving primary goals and a key aspect of effective management of facilities. This paper aims at providing an understanding of the role and function of strategic management in creating and sustaining an effective maintenance management system in an organisation. The background provides an articulated concept and principles of strategic management. The theoretical concepts paved way for a conceptual framework for which strategic management can be integrated into the maintenance management system of an organisation to improve effectiveness in the maintenance of facilities.

Keywords: facilities, maintenance management, organisations, strategic management

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2843 Curve Designing Using an Approximating 4-Point C^2 Ternary Non-Stationary Subdivision Scheme

Authors: Muhammad Younis

Abstract:

A ternary 4-point approximating non-stationary subdivision scheme has been introduced that generates the family of $C^2$ limiting curves. The theory of asymptotic equivalence is being used to analyze the convergence and smoothness of the scheme. The comparison of the proposed scheme has been demonstrated using different examples with the existing 4-point ternary approximating schemes, which shows that the limit curves of the proposed scheme behave more pleasantly and can generate conic sections as well.

Keywords: ternary, non-stationary, approximation subdivision scheme, convergence and smoothness

Procedia PDF Downloads 477
2842 Sustainable Maintenance Model for Infrastructure in Egypt

Authors: S. Hasan, I. Beshara

Abstract:

Infrastructure maintenance is a great challenge facing sustainable development of infrastructure assets due to the high cost of passive implementation of a sustainable maintenance plan. An assessment model of sustainable maintenance for highway infrastructure projects in Egypt is developed in this paper. It helps in improving the implementation of sustainable maintenance criteria. Thus, this paper has applied the analytical hierarchy processes (AHP) to rank and explore the weight of 26 assessment indicators using three hierarchy levels containing the main sustainable categories and subcategories with related indicators. Overall combined weight of each indicator for sustainable maintenance evaluation has been calculated to sum up to a sustainable maintenance performance index (SMI). The results show that the factor "Preventive maintenance cost" has the highest relative contribution factor among others (13.5%), while two factors of environmental performance have the least weights (0.7%). The developed model aims to provide decision makers with information about current maintenance performance and support them in the decision-making process regarding future directions of maintenance activities. It can be used as an assessment performance tool during the operation and maintenance stage. The developed indicators can be considered during designing the maintenance plan. Practices for successful implementation of the model are also presented.

Keywords: analytical hierarchy process, assessment performance Model, KPIs for sustainable maintenance, sustainable maintenance index

Procedia PDF Downloads 138
2841 Reliability-Centered Maintenance Application for the Development of Maintenance Strategy for a Cement Plant

Authors: Nabil Hameed Al-Farsi

Abstract:

This study’s main goal is to develop a model and a maintenance strategy for a cement factory called Arabian Cement Company, Rabigh Plant. The proposed work here depends on Reliability centric maintenance approach to develop a strategy and maintenance schedule that ensures increasing the reliability of the production system components, thus ensuring continuous productivity. The cost-effective maintenance of the plant’s dependability performance is the key goal of durability-based maintenance is. The cement plant consists of 7 important steps, so, developing a maintenance plan based on Reliability centric maintenance (RCM) method is made up of 10 steps accordingly starting from selecting units and data until performing and updating the model. The processing unit chosen for the analysis of this case is the calcinatory unit regarding model’s validation and the Travancore Titanium Products Ltd (TTP) using the claimed data history acquired from the maintenance department maintenance from the mentioned company. After applying the proposed model, the results of the maintenance simulation justified the plant's existing scheduled maintenance policy being reconsidered. Results represent the need for preventive maintenance for all Class A criticality equipment instead of the planned maintenance and the breakdown one for all other equipment depends on its criticality and an FMEA report. Consequently, the additional cost of preventive maintenance would be offset by the cost savings from breakdown maintenance for the remaining equipment.

Keywords: engineering, reliability, strategy, maintenance, failure modes, effects and criticality analysis (FMEA)

Procedia PDF Downloads 171
2840 Omni-Relay (OR) Scheme-Aided LTE-A Communication Systems

Authors: Hassan Mahasneh, Abu Sesay

Abstract:

We propose the use of relay terminals at the cell edge of an LTE-based cellar system. Each relay terminal is equipped with an omni-directional antenna. We refer to this scheme as the Omni-Relay (OR) scheme. The OR scheme coordinates the inter-cell interference (ICI) stemming from adjacent cells and increases the desired signal level at cell-edge regions. To validate the performance of the OR scheme, we derive the average signal-to-interference plus noise ratio (SINR) and the average capacity and compare it with the conventional universal frequency reuse factor (UFRF). The results show that the proposed OR scheme provides higher average SINR and average capacity compared to the UFRF due to the assistance of the distributed relay nodes.

Keywords: the UFRF scheme, the OR scheme, ICI, relay terminals, SINR, spectral efficiency

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2839 Efficient Iterative V-BLAST Detection Technique in Wireless Communication System

Authors: Hwan-Jun Choi, Sung-Bok Choi, Hyoung-Kyu Song

Abstract:

Recently, among the MIMO-OFDM detection techniques, a lot of papers suggested V-BLAST scheme which can achieve high data rate. Therefore, the signal detection of MIMOOFDM system is important issue. In this paper, efficient iterative VBLAST detection technique is proposed in wireless communication system. The proposed scheme adjusts the number of candidate symbol and iterative scheme based on channel state. According to the simulation result, the proposed scheme has better BER performance than conventional schemes and similar BER performance of the QRD-M with iterative scheme. Moreover complexity of proposed scheme has 50.6 % less than complexity of QRD-M detection with iterative scheme. Therefore the proposed detection scheme can be efficiently used in wireless communication.

Keywords: MIMO-OFDM, V-BLAST, QR-decomposition, QRDM, DFE, iterative scheme, channel condition

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2838 Maintenance Management Practice for Building

Authors: Harold Jideofor Nnachetam

Abstract:

Maintenance management in Nigeria Polytechnic faced many issues due to poor service delivery, inadequate finance, and poor maintenance plan and maintenance backlogs. The purpose of this study is to improve the conventional method practices which tend to be ineffective in Nigeria Polytechnic. The case study was conducted with eight Polytechnics in Nigeria. The selected Polytechnic is based on conventional method practices and its major problems, attempt to implement computerized technology and the willingness of staff to share their experiences. All feedbacks from respondents through semi-structured interview were recorded using video camera and transcribed verbatim. The overall findings of this research indicated; poor service delivery, inadequate financial, poor maintenance planning and maintenance backlogs. There is also need to overcome less man power competencies of maintenance management practices which existed with all eight Polytechnics. In addition, the study also found that the Polytechnics still use conventional maintenance management processes in managing building facility condition. As a result, the maintenance management staff was not able to improve the maintenance management performance at the Polytechnics. The findings are intended to be used for maintenance management practices at Nigeria Polytechnics in order to provide high-quality of building facility with safe and healthy environments.

Keywords: maintenance management, conventional method, maintenance management system, Nigeria polytechnic

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2837 Educational Plan and Program of the Subject: Maintenance of Electric Power Equipment

Authors: Rade M. Ciric, Sasa Mandic

Abstract:

Students of Higher Education Technical School of Professional Studies, in Novi Sad follow the subject Maintenance of electric power equipment at the Electrotechnical Department. This paper presents educational plan and program of the subject Maintenance of electric power equipment. The course deals with the problems of preventive and investing maintenance of transformer stations (TS), performing and maintenance of grounding of TS and pillars, as well as tracing and detection the location of the cables failure. There is a special elaborated subject concerning the safe work conditions for the electrician during network maintenance, as well as the basics of making and keeping technical documentation of the equipment.

Keywords: educational plan and program, electric power equipment, maintenance, technical documentation, safe work

Procedia PDF Downloads 467
2836 Contribution to the Decision-Making Process for Selecting the Suitable Maintenance Policy

Authors: Nasser Y. Mahamoud, Pierre Dehombreux, Hassan E. Robleh

Abstract:

Industrial companies may be confronted with questions about their choice of maintenance policy. This choice must be guided by several numbers of decision criteria or objectives related to their production or service activities but also to their level of development and their investment prospects. A decision-support methodology to choose a maintenance policy (corrective, systematic or conditional preventive, predictive, opportunistic or not) is proposed to facilitate this choice using the main categories of the most important decision criteria. The different steps of this methodology are illustrated using theoretical case: identification of the different maintenance alternatives, determining the structure of the most important categories of the decision criteria, assessing the different maintenance policies on to the criteria by using an ordinal preference relation, and finally ranking the different maintenance policies.

Keywords: maintenance policy, decision criteria, decision-making process, AHP

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2835 Efficient Variable Modulation Scheme Based on Codebook in the MIMO-OFDM System

Authors: Yong-Jun Kim, Jae-Hyun Ro, Chang-Bin Ha, Hyoung-Kyu Song

Abstract:

Because current wireless communication requires high reliability in a limited bandwidth environment, this paper proposes the variable modulation scheme based on the codebook. The variable modulation scheme adjusts transmission power using the codebook in accordance with hannel state. Also, if the codebook is composed of many bits, the reliability is more improved by the proposed scheme. The simulation results show that the performance of proposed scheme has better reliability than the the performance of conventional scheme.

Keywords: MIMO-OFDM, variable modulation, codebook, channel state

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2834 Pavement Maintenance and Rehabilitation Scheduling Using Genetic Algorithm Based Multi Objective Optimization Technique

Authors: Ashwini Gowda K. S, Archana M. R, Anjaneyappa V

Abstract:

This paper presents pavement maintenance and management system (PMMS) to obtain optimum pavement maintenance and rehabilitation strategies and maintenance scheduling for a network using a multi-objective genetic algorithm (MOGA). Optimal pavement maintenance & rehabilitation strategy is to maximize the pavement condition index of the road section in a network with minimum maintenance and rehabilitation cost during the planning period. In this paper, NSGA-II is applied to perform maintenance optimization; this maintenance approach was expected to preserve and improve the existing condition of the highway network in a cost-effective way. The proposed PMMS is applied to a network that assessed pavement based on the pavement condition index (PCI). The minimum and maximum maintenance cost for a planning period of 20 years obtained from the non-dominated solution was found to be 5.190x10¹⁰ ₹ and 4.81x10¹⁰ ₹, respectively.

Keywords: genetic algorithm, maintenance and rehabilitation, optimization technique, pavement condition index

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2833 A Cooperative Space-Time Transmission Scheme Based On Symbol Combinations

Authors: Keunhong Chae, Seokho Yoon

Abstract:

This paper proposes a cooperative Alamouti space time transmission scheme with low relay complexity for the cooperative communication systems. In the proposed scheme, the source node combines the data symbols to construct the Alamouti-coded form at the destination node, while the conventional scheme performs the corresponding operations at the relay nodes. In simulation results, it is shown that the proposed scheme achieves the second order cooperative diversity while maintaining the same bit error rate (BER) performance as that of the conventional scheme.

Keywords: Space-time transmission, cooperative communication system, MIMO.

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2832 A Fuzzy Analytic Hierarchy Process Approach for the Decision of Maintenance Priorities of Building Entities: A Case Study in a Facilities Management Company

Authors: Wai Ho Darrell Kwok

Abstract:

Building entities are valuable assets of a society, however, all of them are suffered from the ravages of weather and time. Facilitating onerous maintenance activities is the only way to either maintain or enhance the value and contemporary standard of the premises. By the way, maintenance budget is always bounded by the corresponding threshold limit. In order to optimize the limited resources allocation in carrying out maintenance, there is a substantial need to prioritize maintenance work. This paper reveals the application of Fuzzy AHP in a Facilities Management Company determining the maintenance priorities on the basis of predetermined criteria, viz., Building Status (BS), Effects on Fabrics (EF), Effects on Sustainability (ES), Effects on Users (EU), Importance of Usage (IU) and Physical Condition (PC) in dealing with categorized 8 predominant building components maintenance aspects for building premises. From the case study, it is found that ‘building exterior repainting or re-tiling’, ‘spalling concrete repair works among exterior area’ and ‘lobby renovation’ are the top three maintenance priorities from facilities manager and maintenance expertise personnel. Through the application of the Fuzzy AHP for maintenance priorities decision algorithm, a more systemic and easier comparing scalar linearity factors being explored even in considering other multiple criteria decision scenarios of building maintenance issue.

Keywords: building maintenance, fuzzy AHP, maintenance priority, multi-criteria decision making

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2831 Optimal Maintenance Clustering for Rail Track Components Subject to Possession Capacity Constraints

Authors: Cuong D. Dao, Rob J.I. Basten, Andreas Hartmann

Abstract:

This paper studies the optimal maintenance planning of preventive maintenance and renewal activities for components in a single railway track when the available time for maintenance is limited. The rail-track system consists of several types of components, such as rail, ballast, and switches with different preventive maintenance and renewal intervals. To perform maintenance or renewal on the track, a train free period for maintenance, called a possession, is required. Since a major possession directly affects the regular train schedule, maintenance and renewal activities are clustered as much as possible. In a highly dense and utilized railway network, the possession time on the track is critical since the demand for train operations is very high and a long possession has a severe impact on the regular train schedule. We present an optimization model and investigate the maintenance schedules with and without the possession capacity constraint. In addition, we also integrate the social-economic cost related to the effects of the maintenance time to the variable possession cost into the optimization model. A numerical example is provided to illustrate the model.

Keywords: rail-track components, maintenance, optimal clustering, possession capacity

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2830 Assessment of the Effect of Maintenance Practices on Tourist’s Patronage in Yankari Resort and Safari Nigeria

Authors: Eldah Ephraim Buba

Abstract:

The study is aimed at assessing the effect of maintenance practices on tourist patronage. Yankari resort and Safari had a patronage of twenty thousand, three hundred and two international and national tourists in two thousand and ten, fourteen thousand nine hundred and sixty two, in two thousand and eleven and ten thousand six hundred and one, in two thousand and twelve. The number of tourists keeps falling as the resort has been witnessing low patronage. Personal observation has shown that the state of facilities in the resort is bad. This study aims to appraise maintenance practices in the resort and how it affects tourist patronage. Standard checklist was used for the appraisal of facilities, while questionnaires were administered to tourists to examine whether maintenance practices in the resort do affect their patronage. Findings show that Operational maintenance was poorly carried out while repairs maintenance was fairly done. The study also discovered that there is significant relationship between maintenance practices and tourist patronage. It is recommended that adequate repairs and operational maintenance practices should be carried out in the resort to encourage tourist patronage.

Keywords: maintenance, practices, tourist, patronage

Procedia PDF Downloads 302
2829 Cooperative Sensing for Wireless Sensor Networks

Authors: Julien Romieux, Fabio Verdicchio

Abstract:

Wireless Sensor Networks (WSNs), which sense environmental data with battery-powered nodes, require multi-hop communication. This power-demanding task adds an extra workload that is unfairly distributed across the network. As a result, nodes run out of battery at different times: this requires an impractical individual node maintenance scheme. Therefore we investigate a new Cooperative Sensing approach that extends the WSN operational life and allows a more practical network maintenance scheme (where all nodes deplete their batteries almost at the same time). We propose a novel cooperative algorithm that derives a piecewise representation of the sensed signal while controlling approximation accuracy. Simulations show that our algorithm increases WSN operational life and spreads communication workload evenly. Results convey a counterintuitive conclusion: distributing workload fairly amongst nodes may not decrease the network power consumption and yet extend the WSN operational life. This is achieved as our cooperative approach decreases the workload of the most burdened cluster in the network.

Keywords: cooperative signal processing, signal representation and approximation, power management, wireless sensor networks

Procedia PDF Downloads 390