Search results for: delay analysis for construction projects
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10107

Search results for: delay analysis for construction projects

10047 New Delay-Dependent Stability Criteria for Neural Networks With Two Additive Time-varying Delay Components

Authors: Xingyuan Qu, Shouming Zhong

Abstract:

In this paper, the problem of stability criteria of neural networks (NNs) with two-additive time-varying delay compenents is investigated. The relationship between the time-varying delay and its lower and upper bounds is taken into account when estimating the upper bound of the derivative of Lyapunov functional. As a result, some improved delay stability criteria for NNs with two-additive time-varying delay components are proposed. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.

Keywords: Delay-dependent stability, time-varying delays, Lyapunov functional, linear matrix inequality (LMI).

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10046 Study of the Effect of Project Management on Manufacturing and Production Projects

Authors: S.B. Ahmadi, Z. Moradpour, Gh. Liaghat

Abstract:

In this article the accumulated results out of the effects and length of the manufacture and production projects in the university and research standard have been settled with the usefulness definition of the process of project management for the accessibility to the proportional pattern in the “time and action" stages. Studies show that many problems confronted by the researchers in these projects are connected to the non-profiting of: 1) autonomous timing for gathering the educational theme, 2) autonomous timing for planning and pattern, presenting before the construction, and 3) autonomous timing for manufacture and sample presentation from the output. The result of this study indicates the division of every manufacture and production projects into three smaller autonomous projects from its kind, budget and autonomous expenditure, shape and order of the stages for the management of these kinds of projects. In this case study real result are compared with theoretical results.

Keywords: Project management, Manufacturing, production.

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10045 An Efficient Algorithm for Delay Delay-variation Bounded Least Cost Multicast Routing

Authors: Manas Ranjan Kabat, Manoj Kumar Patel, Chita Ranjan Tripathy

Abstract:

Many multimedia communication applications require a source to transmit messages to multiple destinations subject to quality of service (QoS) delay constraint. To support delay constrained multicast communications, computer networks need to guarantee an upper bound end-to-end delay from the source node to each of the destination nodes. This is known as multicast delay problem. On the other hand, if the same message fails to arrive at each destination node at the same time, there may arise inconsistency and unfairness problem among users. This is related to multicast delayvariation problem. The problem to find a minimum cost multicast tree with delay and delay-variation constraints has been proven to be NP-Complete. In this paper, we propose an efficient heuristic algorithm, namely, Economic Delay and Delay-Variation Bounded Multicast (EDVBM) algorithm, based on a novel heuristic function, to construct an economic delay and delay-variation bounded multicast tree. A noteworthy feature of this algorithm is that it has very high probability of finding the optimal solution in polynomial time with low computational complexity.

Keywords: EDVBM, Heuristic algorithm, Multicast tree, QoS routing, Shortest path.

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10044 Delay and Energy Consumption Analysis of Conventional SRAM

Authors: Arash Azizi-Mazreah, Mohammad T. Manzuri Shalmani, Hamid Barati, Ali Barati

Abstract:

The energy consumption and delay in read/write operation of conventional SRAM is investigated analytically as well as by simulation. Explicit analytical expressions for the energy consumption and delay in read and write operation as a function of device parameters and supply voltage are derived. The expressions are useful in predicting the effect of parameter changes on the energy consumption and speed as well as in optimizing the design of conventional SRAM. HSPICE simulation in standard 0.25μm CMOS technology confirms precision of analytical expressions derived from this paper.

Keywords: Read energy consumption, write energy consumption, read delay, write delay.

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10043 Challenges and Opportunities of E-Procurement in the Construction Industry

Authors: Mansur Hamma-adama, Abdul-Basit Sa’eed Ahmad

Abstract:

Construction Industry is evolving amid the fourth industrial revolution. Transportation, commerce, manufacturing and many other industries ripened the current technological advancement and are striving to utilise every development in the IT sector. The procurement of construction works is known to be very conventional and backward in the adoption of digitalisation. The construction industry's procurement and supply chain are blamed for the most inflated cost of construction projects, mainly attributed to a lack of transparency and trust between the industry stakeholders. This research explores the challenges of e-procurement adoption in the industry and identifies the potential opportunities for its usage. This investigation's data are acquired through interviews, and the data are analysed using qualitative content analysis. This study reveals compounding challenges (i.e., corruption and lack of commitment) that lead to the failure of such efforts in Nigeria and the potential prospects (i.e., transparency and efficiency). This study is essential in developing a more effective and transparent process of procurement so that the Nigerian construction industry is not be left behind in the fast-digitalising markets.

Keywords: Challenges, construction industry, corruption, e-procurement, Nigeria, opportunities.

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10042 Public-Private Partnership Projects in Canada: A Case Study Approach

Authors: Samuel Carpintero

Abstract:

Public-private partnerships (PPP) arrangements have been extensively used in Canada, where the participation of private companies in financing and managing infrastructure projects has increased significantly in the last decade, particularly in the transportation sector. This paper analyses the evolution of the PPP market for transportation projects in Canada and examines the participation of Spanish developers in this market, which have been particularly successful in winning PPP contracts during the last decade.

Keywords: PPP, concession, infrastructure, construction.

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10041 A Relational Case-Based Reasoning Framework for Project Delivery System Selection

Authors: Yang Cui, Yong Qiang Chen

Abstract:

An appropriate project delivery system (PDS) is crucial to the success of a construction projects. Case-based Reasoning (CBR) is a useful support for PDS selection. However, the traditional CBR approach represents cases as attribute-value vectors without taking relations among attributes into consideration, and could not calculate the similarity when the structures of cases are not strictly same. Therefore, this paper solves this problem by adopting the Relational Case-based Reasoning (RCBR) approach for PDS selection, considering both the structural similarity and feature similarity. To develop the feature terms of the construction projects, the criteria and factors governing PDS selection process are first identified. Then feature terms for the construction projects are developed. Finally, the mechanism of similarity calculation and a case study indicate how RCBR works for PDS selection. The adoption of RCBR in PDS selection expands the scope of application of traditional CBR method and improves the accuracy of the PDS selection system.

Keywords: Relational Cased-based Reasoning, Case-based Reasoning, Project delivery system, Selection.

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10040 Qualitative Survey on Managing Building Maintenance Projects

Authors: Edmond W.M. Lam, Albert P.C. Chan, Daniel W.M. Chan

Abstract:

Buildings are one of the valuable assets to provide people with shelters for work, leisure and rest. After years of attacks by weather, buildings will deteriorate which need proper maintenance in order to fulfill the requirements and satisfaction of the users. Poorly managed buildings not just give a negative image to the city itself, but also pose potential risk hazards to the health and safety of the general public. As a result, the management of maintenance projects has played an important role in cities like Hong Kong where the problem of urban decay has drawn much attention. However, most research has focused on managing new construction, and little research effort has been put on maintenance projects. Given the short duration and more diversified nature of work, repair and maintenance works are found to be more difficult to monitor and regulate when compared with new works. Project participants may face with problems in running maintenance projects which should be investigated so that proper strategies can be established. This paper aims to provide a thorough analysis on the problems of running maintenance projects. A review of literature on the characteristics of building maintenance projects was firstly conducted, which forms a solid basis for the empirical study. Results on the problems and difficulties of running maintenance projects from the viewpoints of industry practitioners will also be delivered with a view to formulating effective strategies for managing maintenance projects successfully.

Keywords: characteristics, problems, building maintenance, Hong Kong

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10039 Performance Analysis of Space-Time Trellis Coded OFDM System

Authors: Yi Hong, Zhao Yang Dong

Abstract:

This paper presents the performance analysis of space-time trellis codes in orthogonal frequency division multiplexing systems (STTC-OFDMs) over quasi-static frequency selective fading channels. In particular, the effect of channel delay distributions on the code performance is discussed. For a STTCOFDM over multiple-tap channels, two extreme conditions that produce the largest minimum determinant are highlighted. The analysis also proves that the corresponding coding gain increases with the maximum tap delay. The performance of STTC-OFDM, under various channel conditions, is evaluated by simulation. It is shown that the simulation results agree with the performance analysis.

Keywords: Space-time trellis code, OFDM, delay profile.

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10038 Estimation of Attenuation and Phase Delay in Driving Voltage Waveform of an Ultra-High-Speed Image Sensor by Dimensional Analysis

Authors: V. T. S. Dao, T. G. Etoh, C. Vo Le, H. D. Nguyen, K. Takehara, T. Akino, K. Nishi

Abstract:

We present an explicit expression to estimate driving voltage attenuation through RC networks representation of an ultrahigh- speed image sensor. Elmore delay metric for a fundamental RC chain is employed as the first-order approximation. By application of dimensional analysis to SPICE simulation data, we found a simple expression that significantly improves the accuracy of the approximation. Estimation error of the resultant expression for uniform RC networks is less than 2%. Similarly, another simple closed-form model to estimate 50 % delay through fundamental RC networks is also derived with sufficient accuracy. The framework of this analysis can be extended to address delay or attenuation issues of other VLSI structures.

Keywords: Dimensional Analysis, Elmore model, RC network, Signal Attenuation, Ultra-High-Speed Image Sensor.

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10037 3D Printing Technology in Housing Projects Construction

Authors: Mohammed F. Haddad, Mohammad A. Albenayyan

Abstract:

Realistically, 3-D printing as a technology has not yet reached the required maturity level to handle construction housing projects for citizens on a country scale. However, potentially, it has all of the required elements for addressing this issue. There are two main high-level elements of this technology that need to be capitalized on in order for the technology to reach its full potential: technical and logistical. This paper aims to cover how 3-D printing can be a viable technical solution for housing projects and describes the impact of 3-D printing technical features on the logistical aspects of completing a housing project. Additionally, a perspective about 3-D printing in Saudi Arabia will be presented in order to give the reader an idea of where the Kingdom stands in the deployment of this technology. Finally, a glimpse will be given regarding the potential utilization of this technology for space applications.

Keywords: Large-scale 3-D printing, additive manufacturing, D-shape, contour crafting.

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10036 Contextual Factors in the Decision Making of Industrialized Building System Technology

Authors: S. A. S. Zakaria, G. Brewer, T. Gajendran

Abstract:

Currently, the Malaysian construction industry is focusing on transforming construction processes from conventional building methods to the Industrialized Building System (IBS). Still, research on the decision making of IBS technology adoption with the influence of contextual factors is scarce. The purpose of this paper is to explore how contextual factors influence the IBS decision making in building projects which is perceived by those involved in construction industry namely construction stakeholders and IBS supply chain members. Theoretical background, theoretical frameworks and literatures which identify possible contextual factors that influence decision making towards IBS technology adoption are presented. This paper also discusses the importance of contextual factors in IBS decision making, highlighting some possible crossover benefits and making some suggestions as to how these can be utilized. Conclusions are drawn and recommendations are made with respect to the perception of socio-economic, IBS policy and IBS technology associated with building projects.

Keywords: decision making, technology adoptions, contextualfactors, Industrialized Building Systems

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10035 Analysis of Delay and Throughput in MANET for DSR Protocol

Authors: Kumar Manoj, Ramesh Kumar, Kumari Arti

Abstract:

A wireless Ad-hoc network consists of wireless nodes communicating without the need for a centralized administration, in which all nodes potentially contribute to the routing process.In this paper, we report the simulation results of four different scenarios for wireless ad hoc networks having thirty nodes. The performances of proposed networks are evaluated in terms of number of hops per route, delay and throughput with the help of OPNET simulator. Channel speed 1 Mbps and simulation time 600 sim-seconds were taken for all scenarios. For the above analysis DSR routing protocols has been used. The throughput obtained from the above analysis (four scenario) are compared as shown in Figure 3. The average media access delay at node_20 for two routes and at node_20 for four different scenario are compared as shown in Figures 4 and 5. It is observed that the throughput will degrade when it will follow different hops for same source to destination (i.e. it has dropped from 1.55 Mbps to 1.43 Mbps which is around 9.7%, and then dropped to 0.48Mbps which is around 35%).

Keywords: Throughput, Delay, DSR, OPNET, MANET, DSSS

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10034 Delay-Dependent Stability Criteria for Linear Time-Delay System of Neutral Type

Authors: Myeongjin Park, Ohmin Kwon, Juhyun Park, Sangmoon Lee

Abstract:

This paper proposes improved delay-dependent stability conditions of the linear time-delay systems of neutral type. The proposed methods employ a suitable Lyapunov-Krasovskii’s functional and a new form of the augmented system. New delay-dependent stability criteria for the systems are established in terms of Linear matrix inequalities (LMIs) which can be easily solved by various effective optimization algorithms. Numerical examples showed that the proposed method is effective and can provide less conservative results.

Keywords: Neutral systems, Time-delay, Stability, Lyapunovmethod, LMI.

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10033 Self-tuned LMS Algorithm for Sinusoidal Time Delay Tracking

Authors: Jonah Gamba

Abstract:

In this paper the problem of estimating the time delay between two spatially separated noisy sinusoidal signals by system identification modeling is addressed. The system is assumed to be perturbed by both input and output additive white Gaussian noise. The presence of input noise introduces bias in the time delay estimates. Normally the solution requires a priori knowledge of the input-output noise variance ratio. We utilize the cascade of a self-tuned filter with the time delay estimator, thus making the delay estimates robust to input noise. Simulation results are presented to confirm the superiority of the proposed approach at low input signal-to-noise ratios.

Keywords: LMS algorithm, Self-tuned filter, Systemidentification, Time delay estimation, .

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10032 Achieving Design-Stage Elemental Cost Planning Accuracy: Case Study of New Zealand

Authors: Johnson Adafin, James O. B. Rotimi, Suzanne Wilkinson, Abimbola O. Windapo

Abstract:

An aspect of client expenditure management that requires attention is the level of accuracy achievable in design-stage elemental cost planning. This has been a major concern for construction clients and practitioners in New Zealand (NZ). Pre-tender estimating inaccuracies are significantly influenced by the level of risk information available to estimators. Proper cost planning activities should ensure the production of a project’s likely construction costs (initial and final), and subsequent cost control activities should prevent unpleasant consequences of cost overruns, disputes and project abandonment. If risks were properly identified and priced at the design stage, observed variance between design-stage elemental cost plans (ECPs) and final tender sums (FTS) (initial contract sums) could be reduced. This study investigates the variations between design-stage ECPs and FTS of construction projects, with a view to identifying risk factors that are responsible for the observed variance. Data were sourced through interviews, and risk factors were identified by using thematic analysis. Access was obtained to project files from the records of study participants (consultant quantity surveyors), and document analysis was employed in complementing the responses from the interviews. Study findings revealed the discrepancies between ECPs and FTS in the region of -14% and +16%. It is opined in this study that the identified risk factors were responsible for the variability observed. The values obtained from the analysis would enable greater accuracy in the forecast of FTS by Quantity Surveyors. Further, whilst inherent risks in construction project developments are observed globally, these findings have important ramifications for construction projects by expanding existing knowledge on what is needed for reasonable budgetary performance and successful delivery of construction projects. The findings contribute significantly to the study by providing quantitative confirmation to justify the theoretical conclusions generated in the literature from around the world. This therefore adds to and consolidates existing knowledge.

Keywords: Accuracy, design-stage, elemental cost plan, final tender sum, New Zealand.

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10031 Renovation Planning Model for a Shopping Mall

Authors: Hsin-Yun Lee

Abstract:

In this study, the pedestrian simulation VISWALK integration and application platform ant algorithms written program made to construct a renovation engineering schedule planning mode. The use of simulation analysis platform construction site when the user running the simulation, after calculating the user walks in the case of construction delays, the ant algorithm to find out the minimum delay time schedule plan, and add volume and unit area deactivated loss of business computing, and finally to the owners and users of two different positions cut considerations pick out the best schedule planning. To assess and validate its effectiveness, this study constructed the model imported floor of a shopping mall floor renovation engineering cases. Verify that the case can be found from the mode of the proposed project schedule planning program can effectively reduce the delay time and the user's walking mall loss of business, the impact of the operation on the renovation engineering facilities in the building to a minimum.

Keywords: Pedestrian, renovation, schedule, simulation.

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10030 The Relationship between Procurement Strategies and Sustainability Outcomes: A Systematic Literature Review

Authors: Cathy T. Mpanga Kowet, Aghaegbuna Obinna U. Ozumba

Abstract:

This study examined and identified the inconsistencies, relationships, gaps and recurring themes in literature regarding the relationship between procurement strategies employed in the construction projects for sustainable buildings and realization of sustainability goals. A systematic literature review of studies on the relationship between various procurement strategies and attainment of sustainability outcomes was conducted. Using specific terms, papers published between 2002 and 2018 were identified and screened according to an inclusion and exclusion criteria. Current findings reveal that, although the attainment of sustainability goals is achievable with both traditional and contemporary procurement strategies, only projects delivered using modern procurement strategies are capable of meeting and exceeding targeted sustainability objectives. However, traditional procurement strategy remains the preferred method for most green building construction projects. The results suggest implications for decision makers in considering the impact of selected procurement strategies on targeted sustainability goals, in the early stages of sustainable building construction projects. The study shows that there is a gap between the reported appropriate procurement strategies and what is being practiced currently. Theoretically, the study expands on the literature on adoption and diffusion of contemporary procurement strategies, by consolidating existing studies to highlight the current gaps. While the study is at the literature review stage, deductions will serve as basis for field work involving empirical data.

Keywords: Green building, green construction, procurement method, procurement strategy, sustainability objectives, sustainability outcomes.

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10029 Mega Projects and Governmentality

Authors: Sophie Sturup

Abstract:

Mega urban transport projects (MUTPs) are increasingly being used in urban environments to ameliorate the problem of congestion. However, a number of problems with regard to mega projects have been identified. In particular the seemingly institutionalised over estimation of economic benefits and persistent cost over runs, could mean that the wrong projects are selected, and that the projects that are selected cost more than they should. Studies to date have produced a number of solutions to these problems, perhaps most notably, the various methods for the inclusion of the private sector in project provision. However the problems have shown significant intractability in the face of these solutions. This paper provides a detailed examination of some of the problems facing mega projects and then examines Foucault-s theory of 'governmentality' as a possible frame of analysis which might shed light on the intractability of the problems that have been identified, through an identification of the art of government in which MUTPs occur.

Keywords: Michel Foucault, Governmentality, Mega projects, Transport.

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10028 Interconnect Analysis of a Novel Multiplexer Based Full-Adder Cell for Power and Propagation Delay Optimizations

Authors: G.Ramana Murthy, C.Senthilpari, P.Velrajkumar, Lim Tien Sze

Abstract:

The proposed multiplexer-based novel 1-bit full adder cell is schematized by using DSCH2 and its layout is generated by using microwind VLSI CAD tool. The adder cell layout interconnect analysis is performed by using BSIM4 layout analyzer. The adder circuit is compared with other six existing adder circuits for parametric analysis. The proposed adder cell gives better performance than the other existing six adder circuits in terms of power, propagation delay and PDP. The proposed adder circuit is further analyzed for interconnect analysis, which gives better performance than other adder circuits in terms of layout thickness, width and height.

Keywords: Full Adder, Interconnect Analysis, Low-Power, Multiplexer, Propagation Delay, Parametric Analysis.

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10027 Prioritization Assessment of Housing Development Risk Factors: A Fuzzy Hierarchical Process-Based Approach

Authors: Yusuf Garba Baba

Abstract:

The construction industry and housing subsector are fraught with risks that have the potential of negatively impacting on the achievement of project objectives. The success or otherwise of most construction projects depends to large extent on how well these risks have been managed. The recent paradigm shift by the subsector to use of formal risk management approach in contrast to hitherto developed rules of thumb means that risks must not only be identified but also properly assessed and responded to in a systematic manner. The study focused on identifying risks associated with housing development projects and prioritisation assessment of the identified risks in order to provide basis for informed decision. The study used a three-step identification framework: review of literature for similar projects, expert consultation and questionnaire based survey to identify potential risk factors. Delphi survey method was employed in carrying out the relative prioritization assessment of the risks factors using computer-based Analytical Hierarchical Process (AHP) software. The results show that 19 out of the 50 risks significantly impact on housing development projects. The study concludes that although significant numbers of risk factors have been identified as having relevance and impacting to housing construction projects, economic risk group and, in particular, ‘changes in demand for houses’ is prioritised by most developers as posing a threat to the achievement of their housing development objectives. Unless these risks are carefully managed, their effects will continue to impede success in these projects. The study recommends the adoption and use of the combination of multi-technique identification framework and AHP prioritization assessment methodology as a suitable model for the assessment of risks in housing development projects.

Keywords: Risk identification, risk assessment, analytical hierarchical process, multi-criteria decision.

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10026 Uptake of Off-site Construction: Benefit and Future Application

Authors: Faisal Alazzaz, Andrew Whyte

Abstract:

Off-site construction methods have played an important role in the construction sector in the past few decades. It is increasingly becoming a major alternative technique and strategic direction compared to traditional in-situ method. It produces a significant amount of value for the construction industry and the economy more generally. To date, an impressive number of studies have been lunched on the perceived perception of off-site construction. However, it seems that a quantifying benefit on the offsite construction area is lacking. Therefore, this paper examines the recent research literature on the benefits of off- site construction and provides future direction. In the beginning, this paper provides a brief history and current value of the off-site construction followed by a detailed discussion on the benefit of off-site construction. These benefits include but not limited to time saving, quality improvement, relieving skills shortages, cost reduction and productivity improvement. Toward this end, off-site construction should learn from other productive industry similar to services or manufacturing industry by applying operational management tools and techniques with extensive focus on employee empowerment will shed the light on future uptake of Off-site construction. This study is of value in providing scholars have a clear picture of perceived benefit of off-site construction research and give an opportunities for future uptake of off-site method.

Keywords: Building projects, Employer empowerment, Off-site construction benefits, Productivity.

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10025 Contention Window Adjustment in IEEE 802.11-Based Industrial Wireless Networks

Authors: Mohsen Maadani, Seyed Ahmad Motamedi

Abstract:

The use of wireless technology in industrial networks has gained vast attraction in recent years. In this paper, we have thoroughly analyzed the effect of contention window (CW) size on the performance of IEEE 802.11-based industrial wireless networks (IWN), from delay and reliability perspective. Results show that the default values of CWmin, CWmax, and retry limit (RL) are far from the optimum performance due to the industrial application characteristics, including short packet and noisy environment. In this paper, an adaptive CW algorithm (payload-dependent) has been proposed to minimize the average delay. Finally a simple, but effective CW and RL setting has been proposed for industrial applications which outperforms the minimum-average-delay solution from maximum delay and jitter perspective, at the cost of a little higher average delay. Simulation results show an improvement of up to 20%, 25%, and 30% in average delay, maximum delay and jitter respectively.

Keywords: Average Delay, Contention Window, Distributed Coordination Function (DCF), Jitter, Industrial Wireless Network (IWN), Maximum Delay, Reliability, Retry Limit.

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10024 PI Control for Second Order Delay System with Tuning Parameter Optimization

Authors: R. Farkh, K. Laabidi, M. Ksouri

Abstract:

In this paper, we consider the control of time delay system by Proportional-Integral (PI) controller. By Using the Hermite- Biehler theorem, which is applicable to quasi-polynomials, we seek a stability region of the controller for first order delay systems. The essence of this work resides in the extension of this approach to second order delay system, in the determination of its stability region and the computation of the PI optimum parameters. We have used the genetic algorithms to lead the complexity of the optimization problem.

Keywords: Genetic algorithm, Hermit-Biehler theorem, optimization, PI controller, second order delay system, stability region.

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10023 Leader-following Consensus Criterion for Multi-agent Systems with Probabilistic Self-delay

Authors: M.J. Park, K.H. Kim, O.M. Kwon

Abstract:

This paper proposes a delay-dependent leader-following consensus condition of multi-agent systems with both communication delay and probabilistic self-delay. The proposed methods employ a suitable piecewise Lyapunov-Krasovskii functional and the average dwell time approach. New consensus criterion for the systems are established in terms of linear matrix inequalities (LMIs) which can be easily solved by various effective optimization algorithms. Numerical example showed that the proposed method is effective.

Keywords: Multi-agent systems, probabilistic self-delay, consensus, Lyapunov method, LMI.

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10022 Development of a Support Tool for Cost and Schedule Integration Managment at Program Level

Authors: H. J. Yang, R. Z. Jin, I. J. Park, C. T. Hyun

Abstract:

There has been gradual progress of late in construction projects, particularly in big-scale megaprojects. Due to the long-term construction period, however, with large-scale budget investment, lack of construction management technologies, and increase in the incomplete elements of project schedule management, a plan to conduct efficient operations and to ensure business safety is required. In particular, as the project management information system (PMIS) is meant for managing a single project centering on the construction phase, there is a limitation in the management of program-scale businesses like megaprojects. Thus, a program management information system (PgMIS) that includes program-level management technologies is needed to manage multiple projects. In this study, a support tool was developed for managing the cost and schedule information occurring in the construction phase, at the program level. In addition, a case study on the developed support tool was conducted to verify the usability of the system. With the use of the developed support tool program, construction managers can monitor the progress of the entire project and of the individual subprojects in real time.

Keywords: Cost∙Schedule integration management, Supporting Tool, UI, WBS, CBS, introduce PgMIS (Program Management Information System), PMIS (Project Management Information System)

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10021 An Active Rectifier with Time-Domain Delay Compensation to Enhance the Power Conversion Efficiency

Authors: Shao-Ku Kao

Abstract:

This paper presents an active rectifier with time-domain delay compensation to enhance the efficiency. A delay calibration circuit is designed to convert delay time to voltage and adaptive control on/off delay in variable input voltage. This circuit is designed in 0.18 mm CMOS process. The input voltage range is from 2 V to 3.6 V with the output voltage from 1.8 V to 3.4 V. The efficiency can maintain more than 85% when the load from 50 Ω ~ 1500 Ω for 3.6 V input voltage. The maximum efficiency is 92.4 % at output power to be 38.6 mW for 3.6 V input voltage.

Keywords: Wireless power transfer, active diode, delay compensation, time to voltage converter, PCE.

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10020 Delay Specific Investigations on QoS Scheduling Schemes for Real-Time Traffic in Packet Switched Networks

Authors: P.S.Prakash, S.Selvan

Abstract:

Packet switched data network like Internet, which has traditionally supported throughput sensitive applications such as email and file transfer, is increasingly supporting delay-sensitive multimedia applications such as interactive video. These delaysensitive applications would often rather sacrifice some throughput for better delay. Unfortunately, the current packet switched network does not offer choices, but instead provides monolithic best-effort service to all applications. This paper evaluates Class Based Queuing (CBQ), Coordinated Earliest Deadline First (CEDF), Weighted Switch Deficit Round Robin (WSDRR) and RED-Boston scheduling schemes that is sensitive to delay bound expectations for variety of real time applications and an enhancement of WSDRR is proposed.

Keywords: QoS, Delay-sensitive, Queuing delay, Scheduling

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10019 Critical Success Factors of Information Technology Projects

Authors: Md. Athar Imtiaz, Abduljalil S. Al-Mudhary, Md. Taha Mirhashemi, Roslina Ibrahim

Abstract:

Information Technology (IT) is being used by almost all organizations throughout the world. However its success at supporting and improving business is debatable. There is always the risk of IT project failure and studies have proven that a large number of IT projects indeed do fail. There are many components that further the success of IT projects; these have been studied in previous studies. Studies have found the most necessary components for success in software development projects, executive information systems etc. In this study previous literatures that have looked into these success promoting factors have been critically reviewed and analyzed. 15 Critical Success Factors (CSF) of IT projects were enlisted and examined. These factors can be applied to all IT projects and is not specific to a particular type of IT/IS project. A hypothesis was also generated after the evaluation of the factors.

Keywords: Critical Success Factors, CSF, IT Projects, IS Projects, Software Development Projects.

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10018 Reachable Set Bounding Estimation for Distributed Delay Systems with Disturbances

Authors: Li Xu, Shouming Zhong

Abstract:

The reachable set bounding estimation for distributed delay systems with disturbances is a new problem. In this paper,we consider this problem subject to not only time varying delay and polytopic uncertainties but also distributed delay systems which is not studied fully untill now. we can obtain improved non-ellipsoidal reachable set estimation for neural networks with time-varying delay by the maximal Lyapunov-Krasovskii fuctional which is constructed as the pointwise maximum of a family of Lyapunov-Krasovskii fuctionals corresponds to vertexes of uncertain polytope.On the other hand,matrix inequalities containing only one scalar and Matlabs LMI Toolbox is utilized to give a non-ellipsoidal description of the reachable set.finally,numerical examples are given to illustrate the existing results.

Keywords: Reachable set, Distributed delay, Lyapunov-Krasovskii function, Polytopic uncertainties.

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