Search results for: multiple projects
6434 Social Value of Travel Time Savings in Sub-Saharan Africa
Authors: Richard Sogah
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The significance of transport infrastructure investments for economic growth and development has been central to the World Bank’s strategy for poverty reduction. Among the conventional surface transport infrastructures, road infrastructure is significant in facilitating the movement of human capital goods and services. When transport projects (i.e., roads, super-highways) are implemented, they come along with some negative social values (costs), such as increased noise and air pollution for local residents living near these facilities, displaced individuals, etc. However, these projects also facilitate better utilization of existing capital stock and generate other observable benefits that can be easily quantified. For example, the improvement or construction of roads creates employment, stimulates revenue generation (toll), reduces vehicle operating costs and accidents, increases accessibility, trade expansion, safety improvement, etc. Aside from these benefits, travel time savings (TTSs) which are the major economic benefits of urban and inter-urban transport projects and therefore integral in the economic assessment of transport projects, are often overlooked and omitted when estimating the benefits of transport projects, especially in developing countries. The absence of current and reliable domestic travel data and the inability of replicated models from the developed world to capture the actual value of travel time savings due to the large unemployment, underemployment, and other labor-induced distortions has contributed to the failure to assign value to travel time savings when estimating the benefits of transport schemes in developing countries. This omission of the value of travel time savings from the benefits of transport projects in developing countries poses problems for investors and stakeholders to either accept or dismiss projects based on schemes that favor reduced vehicular operating costs and other parameters rather than those that ease congestion, increase average speed, facilitate walking and handloading, and thus save travel time. Given the complex reality in the estimation of the value of travel time savings and the presence of widespread informal labour activities in Sub-Saharan Africa, we construct a “nationally ranked distribution of time values” and estimate the value of travel time savings based on the area beneath the distribution. Compared with other approaches, our method captures both formal sector workers and individuals/people who work outside the formal sector and hence changes in their time allocation occur in the informal economy and household production activities. The dataset for the estimations is sourced from the World Bank, the International Labour Organization, etc.Keywords: road infrastructure, transport projects, travel time savings, congestion, Sub-Sahara Africa
Procedia PDF Downloads 1086433 Evaluation and Selection of Contractors in Construction Projects with a View Supply Chain Management and Utilization of Promthee
Authors: Sara Najiazarpour, Mahsa Najiazarpour
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There are many problems in contracting projects and their performance. At each project stage and due to different reasons, these problems affect cost, time and overall project quality. Hence, in order to increase the efficiency and performance in all levels of the chain and with supply chain management approach, there will be a coordination from the beginning of a project (contractor selection) to the end of project (handover of project). Contractor selection is the foremost part of construction projects which in this multi-criteria decision-making, the best contractor is determined by expert judgment, different variables and their priorities. In this paper for selecting the best contractor, numerous criteria were collected by asking from adept experts and then among them, 16 criteria with highest frequency were considered for questionnaire. This questionnaire was distributed between experts. Cronbach's alpha coefficient was obtained as 72%. Then based on Borda's function 12 important criteria was selected which was categorized in four main criteria and related sub-criteria as follow: Environmental factors and physical equipment: procurement and materials (supplier), company's machines, contractor’s proposed cost estimate - financial capacity: bank turnover and company's assets, the income of tax declaration in last year, Ability to compensate for losses or delays - past performance- records and technical expertise: experts and key personnel, the past technical backgrounds and experiences, employer satisfaction of previous contracts, the number of similar projects was done - standards: rank and field of expertise which company is qualified for and its validity, availability and number of permitted projects done. Then with PROMTHEE method, the criteria were normalized and monitored, finally the best alternative was selected. In this research, qualitative criteria of each company is became a quantitative criteria. Finally, information of some companies was evaluated and the best contractor was selected based on all criteria and their priorities.Keywords: contractor evaluation and selection, project development, supply chain management, PROMTHEE method
Procedia PDF Downloads 726432 Risk Variables and Implications in Nigeria of Publicly Funded Construction Works Cessation
Authors: Nnadi Ezekiel Oluwaseun Ejiofor
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The foundation of this study is the identification of risk variables and their implications on abandoned construction projects in Nigeria. The study's particular goals are to pinpoint the risk factors that lead to the abandonment of public building projects in Nigeria. This study used a hybrid research design that included case studies and descriptive survey research methods. Professionals who work directly in the built environment and are employed by Ministries and Departmental Agencies (MDAs), the public sector, or the private sector are the study's target demographic. This study used a descriptive survey and case study research design to gather data. Nigeria is experiencing a high rate of project abandonment due to housing deficit issues. Factors contributing to this include The study reveals factors contributing to public project abandonment in Abuja FCT include poor cashflow 4.96, inconsistent government policies 4.89, lack of accountability, high corruption, incompetent contractors, non-availability of building materials, lack of utilities, wrong materials, infrastructural facilities, poor planning, and undefined contracts. The study reveals that abandoned projects have a huge impact on the construction industry, such as wastage of resources with a mean value of 3.35, distrust of economic growth, 3.28, and so on. The study found a significant relationship between risk factors and public building construction in Abuja through a T-test value of 0.037, rejecting the null hypothesis and indicating a positive correlation.Keywords: cost, tetfund, construction projects, public university
Procedia PDF Downloads 556431 Impact of Exogenous Risk Factors into Actual Construction Price in PPP Projects
Authors: Saleh Alzahrani, Halim Boussabaine
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Many of Public Private Partnership (PPP) are developed based on a public project is to be awarded to a private party within a one contractual framework. PPP project risks typically include the development and construction of a new asset as well as its operation. Certainly the most severe consequences of risks through the construction period are price and time overruns. These events are among the most generally used situation in value for money analysis risks. The sources of risk change during the time in PPP project. In traditional procurement, the public sector usually has to cover all prices suffering from these risks. At least there is plenty to suggest that price suffering is a norm in some of the projects that are delivered under traditional procurement. This paper will find the impact of exogenous risk factors into actual construction price into PPP projects. The paper will present a brief literature review on PPP risk pricing strategies and then using system dynamics (SD) to analyses of the risks associated with the estimated project price. Based on the finding from these analyses a risk pricing association model is presented and discussed. The paper concludes with thoughts for future research.Keywords: public private partnership (PPP), risk, risk pricing, system dynamics (SD)
Procedia PDF Downloads 5576430 Professional Stakeholders Perspectives on Community Participation in Transit-Oriented Development Projects: A Johannesburg Case Study
Authors: Kofi Quartey, Kola Ijasan
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Achieving densification around transit-oriented development projects has proven the most ideal way of facilitating urban sprawl whilst increasing the mobility of the majority of the urban populations, making parts of the city that were inaccessible, accessible. Johannesburg has undertaken TOD vision, which was initially called the corridors of freedom. The TOD, in line with the Sustainable Development Goal 11, seeks to establish inclusive, sustainable cities and, in line with the Joburg Growth Development Strategy, aims to create an equitable world-class African city. Equity and inclusivity should occur from the onset of planning and implementation of TOD projects through meaningful community participation. Stakeholder engagement literature from various disciplinary backgrounds has documented dissatisfaction of communities regarding the lack of meaningful participation in government-led development initiatives. The views of other project stakeholders such as project policy planners and project implementors and their challenges in undertaking community participation are, however, not taken into account in such instances, leaving room for a biased perspective. Document analysis was undertaken to determine what is expected of the Project stakeholders according to policy and whether they carried out their duties) seven interviews were also conducted with city entities and community representatives to determine their experiences and challenges with community participation in the various TOD projects attributed to the CoF vision. The findings of the study indicated that stakeholder engagement processes were best described as an ‘educative process’; where local communities were limited to being informed from the onset rather than having an active involvement in the planning processes. Most community members felt they were being informed and educated as to what was going to happen in spite of having their views and opinions collected – primarily due to project deadlines and budget constraints, as was confirmed by professional stakeholders. Some community members exhibited reluctance to change due to feelings of having projects being imposed on them, and the implications of the projects on their properties and lifestyles. It is recommended that community participation should remain a participatory and engaging process that creates an exchange of knowledge and understanding in the form of a dialogue between communities and project stakeholders until a consensus is reached.Keywords: stakeholder engagement, transit oriented development, community participation, Johannesburg
Procedia PDF Downloads 1276429 Performance Analysis of Heterogeneous Cellular Networks with Multiple Connectivity
Authors: Sungkyung Kim, Jee-Hyeon Na, Dong-Seung Kwon
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Future mobile networks following 5th generation will be characterized by one thousand times higher gains in capacity; connections for at least one hundred billion devices; user experience capable of extremely low latency and response times. To be close to the capacity requirements and higher reliability, advanced technologies have been studied, such as multiple connectivity, small cell enhancement, heterogeneous networking, and advanced interference and mobility management. This paper is focused on the multiple connectivity in heterogeneous cellular networks. We investigate the performance of coverage and user throughput in several deployment scenarios. Using the stochastic geometry approach, the SINR distributions and the coverage probabilities are derived in case of dual connection. Also, to compare the user throughput enhancement among the deployment scenarios, we calculate the spectral efficiency and discuss our results.Keywords: heterogeneous networks, multiple connectivity, small cell enhancement, stochastic geometry
Procedia PDF Downloads 3316428 Node Pair Selection Scheme in Relay-Aided Communication Based on Stable Marriage Problem
Authors: Tetsuki Taniguchi, Yoshio Karasawa
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This paper describes a node pair selection scheme in relay-aided multiple source multiple destination communication system based on stable marriage problem. A general case is assumed in which all of source, relay and destination nodes are equipped with multiantenna and carry out multistream transmission. Based on several metrics introduced from inter-node channel condition, the preference order is determined about all source-relay and relay-destination relations, and then the node pairs are determined using Gale-Shapley algorithm. The computer simulations show that the effectiveness of node pair selection is larger in multihop communication. Some additional aspects which are different from relay-less case are also investigated.Keywords: relay, multiple input multiple output (MIMO), multiuser, amplify and forward, stable marriage problem, Gale-Shapley algorithm
Procedia PDF Downloads 3976427 Using the UK as a Case Study to Assess the Current State of Large Woody Debris Restoration as a Tool for Improving the Ecological Status of Natural Watercourses Globally
Authors: Isabelle Barrett
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Natural watercourses provide a range of vital ecosystem services, notably freshwater provision. They also offer highly heterogeneous habitat which supports an extreme diversity of aquatic life. Exploitation of rivers, changing land use and flood prevention measures have led to habitat degradation and subsequent biodiversity loss; indeed, freshwater species currently face a disproportionate rate of extinction compared to their terrestrial and marine counterparts. Large woody debris (LWD) encompasses the trees, large branches and logs which fall into watercourses, and is responsible for important habitat characteristics. Historically, natural LWD has been removed from streams under the assumption that it is not aesthetically pleasing and is thus ecologically unfavourable, despite extensive evidence contradicting this. Restoration efforts aim to replace lost LWD in order to reinstate habitat heterogeneity. This paper aims to assess the current state of such restoration schemes for improving fluvial ecological health in the UK. A detailed review of the scientific literature was conducted alongside a meta-analysis of 25 UK-based projects involving LWD restoration. Projects were chosen for which sufficient information was attainable for analysis, covering a broad range of budgets and scales. The most effective strategies for river restoration encompass ecological success, stakeholder engagement and scientific advancement, however few projects surveyed showed sensitivity to all three; for example, only 32% of projects stated biological aims. Focus tended to be on stakeholder engagement and public approval, since this is often a key funding driver. Consequently, there is a tendency to focus on the aesthetic outcomes of a project, however physical habitat restoration does not necessarily lead to direct biodiversity increases. This highlights the significance of rivers as highly heterogeneous environments with multiple interlinked processes, and emphasises a need for a stronger scientific presence in project planning. Poor scientific rigour means monitoring is often lacking, with varying, if any, definitions of success which are rarely pre-determined. A tendency to overlook negative or neutral results was apparent, with unjustified focus often put on qualitative results. The temporal scale of monitoring is typically inadequate to facilitate scientific conclusions, with only 20% of projects surveyed reporting any pre-restoration monitoring. Furthermore, monitoring is often limited to a few variables, with biotic monitoring often fish-focussed. Due to their longer life cycles and dispersal capability, fish are usually poor indicators of environmental change, making it difficult to attribute any changes in ecological health to restoration efforts. Although the potential impact of LWD restoration may be positive, this method of restoration could simply be making short-term, small-scale improvements; without addressing the underlying symptoms of degradation, for example water quality, the issue cannot be fully resolved. Promotion of standardised monitoring for LWD projects could help establish a deeper understanding of the ecology surrounding the practice, supporting movement towards adaptive management in which scientific evidence feeds back to practitioners, enabling the design of more efficient projects with greater ecological success. By highlighting LWD, this study hopes to address the difficulties faced within river management, and emphasise the need for a more holistic international and inter-institutional approach to tackling problems associated with degradation.Keywords: biological monitoring, ecological health, large woody debris, river management, river restoration
Procedia PDF Downloads 2166426 Matlab Method for Exclusive-or Nodes in Fuzzy GERT Networks
Authors: Roland Lachmayer, Mahtab Afsari
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Research is the cornerstone for advancement of human communities. So that it is one of the indexes for evaluating advancement of countries. Research projects are usually cost and time-consuming and do not end in result in short term. Project scheduling is one of the integral parts of project management. The present article offers a new method by using C# and Matlab software to solve Fuzzy GERT networks for Exclusive-OR kind of nodes to schedule the network. In this article we concentrate on flowcharts that we used in Matlab to show how we apply Matlab to schedule Exclusive-OR nodes.Keywords: research projects, fuzzy GERT, fuzzy CPM, CPM, α-cuts, scheduling
Procedia PDF Downloads 3986425 Design of Cloud Service Brokerage System Intermediating Integrated Services in Multiple Cloud Environment
Authors: Dongjae Kang, Sokho Son, Jinmee Kim
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Cloud service brokering is a new service paradigm that provides interoperability and portability of application across multiple Cloud providers. In this paper, we designed cloud service brokerage system, any broker, supporting integrated service provisioning and SLA based service life cycle management. For the system design, we introduce the system concept and whole architecture, details of main components and use cases of primary operations in the system. These features ease the Cloud service provider and customer’s concern and support new Cloud service open market to increase cloud service profit and prompt Cloud service echo system in cloud computing related area.Keywords: cloud service brokerage, multiple Clouds, Integrated service provisioning, SLA, network service
Procedia PDF Downloads 4886424 Web-GIS Technology: A Tool for Farm-to-Market Road Project Profiling and Proposal Prioritization of the Philippines’ Department of Agriculture
Authors: Elbert S. Moyon, Edsel Matt O. Morales, Jaymer M. Jayoma, Kent C. Espejon, Jayson C. Dollete, Mark Phil B. Pacot
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This research paper focuses on the potential of using Web-GIS technology in prioritizing farm-to-market road projects by the Philippines’ Department of Agriculture (DA). The study aimed to explore the benefits of Web-GIS in addressing the limitations faced by the DA in terms of Farm to Market Road profiling and project prioritization, which include a lack of access to updated data, limited spatial analysis capabilities, and difficulties in sharing information between stakeholders. The research methodology involves a comprehensive literature review and a case study of a Web-GIS application developed for the DA, which was used to profile and prioritize farm-to-market road projects in the Philippines. The results showed that the Web-GIS technology provides the DA with an effective tool for analyzing and visualizing data, which can help in profiling and prioritizing road projects based on various criteria such as economic, social, and environmental impacts. The study also showed that Web-GIS technology could help in reducing the time and effort required for road project prioritization and improve communication between stakeholders.Keywords: GIS, web application, farm-to-market road, FMR prioritization, Django, GeoServer
Procedia PDF Downloads 836423 Analyze and Improve Project Delivery Time Enhancing Business Management System of Review and Approval Process for Project Design Submittals
Authors: Abdulaziz Alnajem, Amit Sharma
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Business Case: Project delivery and enhancing activities' completion in the shortest possible time is critical during execution to proceed with the subsequent phases of Procurement, C & C phases of Contracts to have the required Production facilities/Infrastructure in place to achieve the Company strategic objective of 4.0 MBOPD oil production. SOR (Statement of requirement): Design and Engineering phase of Projects execution takes a long time. It is observed that, in most of the cases, company has crossed the Project Design Submittals review time as per the Contract/Company Standards, resulting into delays in projects completion, and cost impact to the company. Study Scope: Scope of the study covers the process from date of first submission of D & E documents by the contractor to final approval by the controlling team to proceed with the procurement of materials. This scope covers projects handled by the company’s project management teams and includes only the internal review process by the company.Keywords: business management system, project management, oil and gas, analysis, improvement, design, delays
Procedia PDF Downloads 2186422 A Method to Identify the Critical Delay Factors for Building Maintenance Projects of Institutional Buildings: Case Study of Eastern India
Authors: Shankha Pratim Bhattacharya
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In general building repair and renovation projects are minor in nature. It requires less attention as the primary cost involvement is relatively small. Although the building repair and maintenance projects look simple, it involves much complexity during execution. Many of the present research indicate that few uncertain situations are usually linked with maintenance projects. Those may not be read properly in the planning stage of the projects, and finally, lead to time overrun. Building repair and maintenance become essential and periodical after commissioning of the building. In Institutional buildings, the regular maintenance projects also include addition –alteration, modification activities. Increase in the student admission, new departments, and sections, new laboratories and workshops, up gradation of existing laboratories are very common in the institutional buildings in the developing nations like India. The project becomes very critical because it undergoes space problem, architectural design issues, structural modification, etc. One of the prime factors in the institutional building maintenance and modification project is the time constraint. Mostly it required being executed a specific non-work time period. The present research considered only the institutional buildings of the Eastern part of India to analyse the repair and maintenance project delay. A general survey was conducted among the technical institutes to find the causes and corresponding nature of construction delay factors. Five technical institutes are considered in the present study with repair, renovation, modification and extension type of projects. Construction delay factors are categorically subdivided into four groups namely, material, manpower (works), Contract and Site. The survey data are collected for the nature of delay responsible for a specific project and the absolute amount of delay through proposed and actual duration of work. In the first stage of the paper, a relative importance index (RII) is proposed for the delay factors. The occurrence of the delay factors is also judged by its frequency-severity nature. Finally, the delay factors are then rated and linked with the type of work. In the second stage, a regression analysis is executed to establish an empirical relationship between the actual time of a project and the percentage of delay. It also indicates the impact of the factors for delay responsibility. Ultimately, the present paper makes an effort to identify the critical delay factors for the repair and renovation type project in the Eastern Indian Institutional building.Keywords: delay factor, institutional building, maintenance, relative importance index, regression analysis, repair
Procedia PDF Downloads 2506421 Price Compensation Mechanism with Unmet Demand for Public-Private Partnership Projects
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Public-private partnership (PPP), as an innovative way to provide infrastructures by the private sector, is being widely used throughout the world. Compared with the traditional mode, PPP emerges largely for merits of relieving public budget constraint and improving infrastructure supply efficiency by involving private funds. However, PPP projects are characterized by large scale, high investment, long payback period, and long concession period. These characteristics make PPP projects full of risks. One of the most important risks faced by the private sector is demand risk because many factors affect the real demand. If the real demand is far lower than the forecasting demand, the private sector will be got into big trouble because operating revenue is the main means for the private sector to recoup the investment and obtain profit. Therefore, it is important to study how the government compensates the private sector when the demand risk occurs in order to achieve Pareto-improvement. This research focuses on price compensation mechanism, an ex-post compensation mechanism, and analyzes, by mathematical modeling, the impact of price compensation mechanism on payoff of the private sector and consumer surplus for PPP toll road projects. This research first investigates whether or not price compensation mechanisms can obtain Pareto-improvement and, if so, then explores boundary conditions for this mechanism. The research results show that price compensation mechanism can realize Pareto-improvement under certain conditions. Especially, to make the price compensation mechanism accomplish Pareto-improvement, renegotiation costs of the government and the private sector should be lower than a certain threshold which is determined by marginal operating cost and distortionary cost of the tax. In addition, the compensation percentage should match with the price cut of the private investor when demand drops. This research aims to provide theoretical support for the government when determining compensation scope under the price compensation mechanism. Moreover, some policy implications can also be drawn from the analysis for better risk-sharing and sustainability of PPP projects.Keywords: infrastructure, price compensation mechanism, public-private partnership, renegotiation
Procedia PDF Downloads 1796420 Application and Verification of Regression Model to Landslide Susceptibility Mapping
Authors: Masood Beheshtirad
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Identification of regions having potential for landslide occurrence is one of the basic measures in natural resources management. Different landslide hazard mapping models are proposed based on the environmental condition and goals. In this research landslide hazard map using multiple regression model were provided and applicability of this model is investigated in Baghdasht watershed. Dependent variable is landslide inventory map and independent variables consist of information layers as Geology, slope, aspect, distance from river, distance from road, fault and land use. For doing this, existing landslides have been identified and an inventory map made. The landslide hazard map is based on the multiple regression provided. The level of similarity potential hazard classes and figures of this model were compared with the landslide inventory map in the SPSS environments. Results of research showed that there is a significant correlation between the potential hazard classes and figures with area of the landslides. The multiple regression model is suitable for application in the Baghdasht Watershed.Keywords: landslide, mapping, multiple model, regression
Procedia PDF Downloads 3236419 Risk Assessment on Construction Management with “Fuzzy Logy“
Authors: Mehrdad Abkenari, Orod Zarrinkafsh, Mohsen Ramezan Shirazi
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Construction projects initiate in complicated dynamic environments and, due to the close relationships between project parameters and the unknown outer environment, they are faced with several uncertainties and risks. Success in time, cost and quality in large scale construction projects is uncertain in consequence of technological constraints, large number of stakeholders, too much time required, great capital requirements and poor definition of the extent and scope of the project. Projects that are faced with such environments and uncertainties can be well managed through utilization of the concept of risk management in project’s life cycle. Although the concept of risk is dependent on the opinion and idea of management, it suggests the risks of not achieving the project objectives as well. Furthermore, project’s risk analysis discusses the risks of development of inappropriate reactions. Since evaluation and prioritization of construction projects has been a difficult task, the network structure is considered to be an appropriate approach to analyze complex systems; therefore, we have used this structure for analyzing and modeling the issue. On the other hand, we face inadequacy of data in deterministic circumstances, and additionally the expert’s opinions are usually mathematically vague and are introduced in the form of linguistic variables instead of numerical expression. Owing to the fact that fuzzy logic is used for expressing the vagueness and uncertainty, formulation of expert’s opinion in the form of fuzzy numbers can be an appropriate approach. In other words, the evaluation and prioritization of construction projects on the basis of risk factors in real world is a complicated issue with lots of ambiguous qualitative characteristics. In this study, evaluated and prioritization the risk parameters and factors with fuzzy logy method by combination of three method DEMATEL (Decision Making Trial and Evaluation), ANP (Analytic Network Process) and TOPSIS (Technique for Order-Preference by Similarity Ideal Solution) on Construction Management.Keywords: fuzzy logy, risk, prioritization, assessment
Procedia PDF Downloads 5946418 SNR Classification Using Multiple CNNs
Authors: Thinh Ngo, Paul Rad, Brian Kelley
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Noise estimation is essential in today wireless systems for power control, adaptive modulation, interference suppression and quality of service. Deep learning (DL) has already been applied in the physical layer for modulation and signal classifications. Unacceptably low accuracy of less than 50% is found to undermine traditional application of DL classification for SNR prediction. In this paper, we use divide-and-conquer algorithm and classifier fusion method to simplify SNR classification and therefore enhances DL learning and prediction. Specifically, multiple CNNs are used for classification rather than a single CNN. Each CNN performs a binary classification of a single SNR with two labels: less than, greater than or equal. Together, multiple CNNs are combined to effectively classify over a range of SNR values from −20 ≤ SNR ≤ 32 dB.We use pre-trained CNNs to predict SNR over a wide range of joint channel parameters including multiple Doppler shifts (0, 60, 120 Hz), power-delay profiles, and signal-modulation types (QPSK,16QAM,64-QAM). The approach achieves individual SNR prediction accuracy of 92%, composite accuracy of 70% and prediction convergence one order of magnitude faster than that of traditional estimation.Keywords: classification, CNN, deep learning, prediction, SNR
Procedia PDF Downloads 1336417 Bi-Objective Optimization for Sustainable Supply Chain Network Design in Omnichannel
Authors: Veerpaul Maan, Gaurav Mishra
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The evolution of omnichannel has revolutionized the supply chain of the organizations by enhancing customer shopping experience. For these organizations need to develop well-integrated multiple distribution channels to leverage the benefits of omnichannel. To adopt an omnichannel system in the supply chain has resulted in structuring and reconfiguring the practices of the traditional supply chain distribution network. In this paper a multiple distribution supply chain network (MDSCN) have been proposed which integrates online giants with a local retailers distribution network in uncertain environment followed by sustainability. To incorporate sustainability, an additional objective function is added to reduce the carbon content through minimizing the travel distance of the product. Through this proposed model, customers are free to access product and services as per their choice of channels which increases their convenience, reach and satisfaction. Further, a numerical illustration is being shown along with interpretation of results to validate the proposed model.Keywords: sustainable supply chain network, omnichannel, multiple distribution supply chain network, integrate multiple distribution channels
Procedia PDF Downloads 2236416 Epileptic Seizures in Patients with Multiple Sclerosis
Authors: Anat Achiron
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Background: Multiple sclerosis (MS) is a chronic autoimmune disease that affects the central nervous system in young adults. It involves the immune system attacking the protective covering of nerve fibers (myelin), leading to inflammation and damage. MS can result in various neurological symptoms, such as muscle weakness, coordination problems, and sensory disturbances. Seizures are not common in MS, and the frequency is estimated between 0.4 to 6.4% over the disease course. Objective: Investigate the frequency of seizures in individuals with multiple sclerosis and to identify associated risk factors. Methods: We evaluated the frequency of seizures in a large cohort of 5686 MS patients followed at the Sheba Multiple Sclerosis Center and studied associated risk factors and comorbidities. Our research was based on data collection using a cohort study design. We applied logistic regression analysis to assess the strength of associations. Results: We found that younger age at onset, longer disease duration, and prolonged time to immunomodulatory treatment initiation were associated with increased risk for seizures. Conclusions: Our findings suggest that seizures in people with MS are directly related to the demyelination process and not associated with other factors like medication side effects or comorbid conditions. Therefore, initiating immunomodulatory treatment early in the disease course could reduce not only disease activity but also decrease seizure risk.Keywords: epilepsy, seizures, multiple sclerosis, white matter, age
Procedia PDF Downloads 716415 The Emergence of Construction Mafia in South Africa: The Implication on the Construction Industry
Authors: Thandokazi Nyangiwe, Christopher Amoah, Charles P. Mukumba
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The South African construction sector is threatened by emerging black business forums called construction mafias. The emergence of the construction mafia has culminated in the disruptions and abandonment of construction sites resulting in the loss of jobs for construction workers. The paper examines the origin of construction mafias and their impact on the construction sector, including the potential ways to cope with their operations. A qualitative research approach was adopted for this study using open-ended interview questions to gather information from 30 key construction industry stakeholders, including contractors, subcontractors, consultants, and the construction project communities. Content and thematic analysis were used to analyse the data collected. The findings suggest that most participants do not fully understand the existence and operations of construction mafias in the construction industry. Construction mafias claim to be part of the local business forums. They disrupt construction projects and demand a certain amount, usually 30% of the construction value. Construction mafias frequently resort to intimidation and violence if their demands are unmet. Their operations have resulted in delayed completion of construction projects, abandonment of projects, and loss of income for the contractor and jobs for the construction workers. The interviews were limited to construction stakeholders. Because of the nature of the mafias’ operations, they could not be accessed for interviews for fear of being identified because of the connotation attached to their role as construction mafias. Construction project owners face disruptions of projects resulting in loss of equipment, materials, and income. Therefore, there is a need to sensitise the construction stakeholders in the construction industry regarding the existence and operations of the construction mafia and the implications on construction project performance and delivery. The findings will give insight into the operations of the construction mafias in the South African construction industry, which has caused disruptions in construction project sites. Stakeholders must find solutions to address the construction mafias’ disruptive actions on construction projects. The study presents an initial inquiry that will come up with how to manage and cope with the growing operations of construction mafias in the South African construction industry.Keywords: black business forums, construction mafia, emergence, implication
Procedia PDF Downloads 1346414 The Effect of Metformin in Combination with Dexamethasone on the CXCR4 Level in Multiple Myeloma Cell Line
Authors: Seyede Sanaz Seyedebrahimi, Shima Rahimi, Shohreh Fakhari, Ali Jalili
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Background: CXCR4, as a chemokine receptor, plays well-known roles in various types of cancers. Several studies have been conducted to overcome CXCR4 axis acts in multiple myeloma (MM) pathogenesis and progression. Dexamethasone, a standard treatment for multiple myeloma, has been shown to increase CXCR4 levels in multiple myeloma cell lines. Herein, we focused on the effects of metformin and dexamethasone on CXCR4 at the cellular level and the migration rate of cell lines after exposure to a combination compared to single-agent models. Materials and Method: Multiple myeloma cell lines (U266 and RPMI8226) were cultured with different metformin and dexamethasone concentrations in single-agent and combination models. The simultaneous combination doses were calculated by CompuSyn software. Cell surface and mRNA expression of CXCR4 were determined using flow cytometry and the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay, respectively. The Transwell cell migration assay evaluated the migration ability. Results: In concurred with previous studies, our results showed a dexamethasone up-regulation effect on CXCR4 in a dose-dependent manner. Although, the metformin single-agent model could reduce CXCR4 expression of U266 and RPMI8226 in cell surface and mRNA expression level. Moreover, the administration of metformin and dexamethasone simultaneously exerted a higher suppression effect on CXCR4 expression than the metformin single-agent model. The migration rate through the combination model's matrigel membrane was remarkably lower than the metformin and dexamethasone single-agent model. Discussion: According to our findings, the combination of metformin and dexamethasone effectively inhibited dexamethasone-induced CXCR4 expression in multiple myeloma cell lines. As a result, metformin may be counted as an alternative medicine combined with other chemotherapies to combat multiple myeloma. However, more research is required.Keywords: CXCR4, dexamethasone, metformin, migration, multiple myeloma
Procedia PDF Downloads 1566413 2D Numerical Modeling of Ultrasonic Measurements in Concrete: Wave Propagation in a Multiple-Scattering Medium
Authors: T. Yu, L. Audibert, J. F. Chaix, D. Komatitsch, V. Garnier, J. M. Henault
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Linear Ultrasonic Techniques play a major role in Non-Destructive Evaluation (NDE) for civil engineering structures in concrete since they can meet operational requirements. Interpretation of ultrasonic measurements could be improved by a better understanding of ultrasonic wave propagation in a multiple scattering medium. This work aims to develop a 2D numerical model of ultrasonic wave propagation in a heterogeneous medium, like concrete, integrating the multiple scattering phenomena in SPECFEM software. The coherent field of multiple scattering is obtained by averaging numerical wave fields, and it is used to determine the effective phase velocity and attenuation corresponding to an equivalent homogeneous medium. First, this model is applied to one scattering element (a cylinder) in a homogenous medium in a linear-elastic system, and its validation is completed thanks to the comparison with analytical solution. Then, some cases of multiple scattering by a set of randomly located cylinders or polygons are simulated to perform parametric studies on the influence of frequency and scatterer size, concentration, and shape. Also, the effective properties are compared with the predictions of Waterman-Truell model to verify its validity. Finally, the mortar viscoelastic behavior is introduced in the simulation in order to considerer the dispersion and the attenuation due to porosity included in the cement paste. In the future, different steps will be developed: The comparisons with experimental results, the interpretation of NDE measurements, and the optimization of NDE parameters before an auscultation.Keywords: attenuation, multiple-scattering medium, numerical modeling, phase velocity, ultrasonic measurements
Procedia PDF Downloads 2756412 Education for Sustainability Using PBL on an Engineering Course at the National University of Colombia
Authors: Hernán G. Cortés-Mora, José I. Péna-Reyes, Alfonso Herrera-Jiménez
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This article describes the implementation experience of Project-Based Learning (PBL) in an engineering course of the Universidad Nacional de Colombia, with the aim of strengthening student skills necessary for the exercise of their profession under a sustainability framework. Firstly, we present a literature review on the education for sustainability field, emphasizing the skills and knowledge areas required for its development, as well as the commitment of the Faculty of Engineering of the Universidad Nacional de Colombia, and other engineering faculties of the country, regarding education for sustainability. This article covers the general aspects of the course, describes how students team were formed, and how their experience was during the first semester of 2017. During this period two groups of students decided to develop their course project aiming to solve a problem regarding a Non-Governmental Organization (NGO) that works with head-of-household mothers in a low-income neighborhood in Bogota (Colombia). Subsequently, we show how sustainability is involved in the course, how tools are provided to students, and how activities are developed as to strengthen their abilities, which allows them to incorporate sustainability in their projects while also working on the methodology used to develop said projects. Finally, we introduce the results obtained by the students who sent the prototypes of their projects to the community they were working on and the conclusions reached by them regarding the course experience.Keywords: sustainability, project-based learning, engineering education, higher education for sustainability
Procedia PDF Downloads 3516411 Progress and Challenges of Smart Cities in India: An Exploratory Study
Authors: Sushil K. Sharma, Jeff Zhang, Saeed Tabar
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Worldwide, several governments are utilizing the Internet of Things (IoT) and other information and communication technologies (ICTs) to create smart city infrastructures to improve both the quality of government services and citizen welfare. Over 700 cities from around the world have already started implementing their smart city projects. Smart City utilizes the network of connected things, or the Internet of Things (IoT), that interconnects devices and various components across city infrastructure, making them work together seamlessly to enhance the quality, performance, and interactivity of urban services, optimize resources, and reduce costs. Without developing smart cities, the accelerating growth of cities, and their disproportionate consumption of physical and social resources are unsustainable. In 2016, the Indian Government released a list of 100 cities with the intention of kick-starting the process of developing them into 'smart cities’ as part of the Smart Cities Mission. This study reports the progress and challenges of Smart City projects in India. The data were collected through the city/state government websites, media reports, and focus group discussions/interviews. The preliminary results indicate that smart city projects are not only behind in their implementation and scope but also lacks the sincerity for its implementation.Keywords: smart city, smart government, Internet of Things, digital government
Procedia PDF Downloads 1826410 Effect of Building Construction Sizes on Project Delivery Methods in Nigeria
Authors: Nuruddeen Usman, Mohammad Sani
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The performance of project delivery methods has been an issue of concern to various stakeholders in the construction industry. The contracting system of project delivery is the traditional system used in the delivery of most public projects in Nigeria. The direct labor system is used most times as an alternative to the traditional system. There were so many complain about the performance of contracting system and the suitability of direct labor as an alternative to the delivery of public projects. Therefore, this paper is aimed at investigating the effect of project size on the project delivery methods in the completed public buildings. Questionnaires were self-administered to managerial staff in the study area and analyzed using descriptive statistics. The findings reveals that contracting system was choosing for large size building construction project delivery with higher frequency (F) of 40 (76.9%) against direct labor with 12 (23.1%). While the small size project, the result revealed a frequency (F) of 26 (50%) for contracting system and direct labor system respectively. Base on the research findings, the contracting system, was recommended for all sizes of building construction project delivery while direct labor system can only use as an alternative for small size building construction projects delivery.Keywords: construction size, contracting system, direct labour, effect
Procedia PDF Downloads 4576409 Proposal Evaluation of Critical Success Factors (CSF) in Lean Manufacturing Projects
Authors: Guilherme Gorgulho, Carlos Roberto Camello Lima
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Critical success factors (CSF) are used to design the practice of project management that can lead directly or indirectly to the success of the project. This management includes many elements that have to be synchronized in order to ensure the project on-time delivery, quality and the lowest possible cost. The objective of this work is to develop a proposal for evaluation of the FCS in lean manufacturing projects, and apply the evaluation in a pilot project. The results show that the use of continuous improvement programs in organizations brings benefits as the process cost reduction and improve productivity.Keywords: continuous improvement, critical success factors (csf), lean thinking, project management
Procedia PDF Downloads 3646408 Execution of Joinery in Large Scale Projects: Middle East Region as a Case Study
Authors: Arsany Philip Fawzy
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This study is going to address the hurdles of project management in the joinery field. It is widely divided into two sections; the first one will shed light on how to execute large-scale projects with a specific focus on the middle east region. It will also raise major obstacles that may face the joinery team from the site clearance and the coordination between the joinery team and the construction team. The second section is going to technically analyze the commercial side of the joinery and how to control the main cost of the project to avoid financial problems. It will also suggest empirical solutions to monitor the cost impact (e.g., Variation of contract quantity and claims).Keywords: clearance, quality, cost, variation, claim
Procedia PDF Downloads 1026407 Study on a Family of Optimal Fourth-Order Multiple-Root Solver
Authors: Young Hee Geum
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In this paper,we develop the complex dynamics of a family of optimal fourth-order multiple-root solvers and plot their basins of attraction. Mobius conjugacy maps and extraneous fixed points applied to a prototype quadratic polynomial raised to the power of the known integer multiplicity m are investigated. A 300 x 300 uniform grid centered at the origin covering 3 x 3 square region is chosen to visualize the initial values on each basin of attraction in accordance with a coloring scheme based on their dynamical behavior. The illustrative basins of attractions applied to various test polynomials and the corresponding statistical data for convergence are shown to confirm the theoretical convergence.Keywords: basin of attraction, conjugacy, fourth-order, multiple-root finder
Procedia PDF Downloads 2936406 Construction Innovation: Support for 3D Printing House
Authors: Andrea Palazzo, Daniel Macek, Veronika Malinova
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Contour processing is the new technology challenge for architects and construction companies. The many advantages it promises make it one of the most interesting solutions for construction in terms of automation of building processes. The technology for 3D printing houses offers many application possibilities, from low-cost construction, to being considered by NASA for visionary projects as a good solution for building settlements on other planets. Another very important point is that clients, as architects, will no longer have many limits in design concerning ideas and creativity. The prices for real estate are constantly increasing and the lack of availability of construction materials as well as the speculation that has been created around it in 2021 is bringing prices to such a level that in the future real estate developers risk not being able to find customers for these ultra-expensive homes. Hence, this paper starts with the introduction of 3D printing, which now has the potential to gain an important position in the market, becoming a valid alternative to the classic construction process. This technology is not only beneficial from an economic point of view but it is also a great opportunity to have an impact on the environment by reducing CO2 emissions. Further on in the article we will also understand if, after the COP 26 (2021 United Nations Climate Change Conference), world governments could also push towards building technologies that reduce the waste materials that are needed to be disposed of and at the same time reduce emissions with the contribution of governmental funds. This paper will give us insight on the multiple benefits of 3D printing and emphasise the importance of finding new solutions for materials that can be used by the printer. Therefore, based on the type of material, it will be possible to understand the compatibility with current regulations and how the authorities will be inclined to support this technology. This will help to enable the rise and development of this technology in Europe and in the rest of the world on actual housing projects and not only on prototypes.Keywords: additive manufacturing, contour crafting, development, new regulation, printing material
Procedia PDF Downloads 1986405 Impact of Construction Risk Factors into Actual Construction Price in PPP Projects
Authors: Saleh Alzahrani, Halim Boussabaine
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The majority of Public Private Partnership (PPP) are developed based on the rationale that the design, construction, operation, and financing of a public project is to be awarded to a private party within a single contractual framework. PPP project risks normally include the development and construction of a new asset as well as its operation for decades. Undoubtedly the most serious consequences of risks during the construction period are price and time overruns. These events are amongst the most broadly used scenarios in value for money analysis risks. The sources of risk change over the life cycle of a PPP project. In traditional procurement, the public sector normally has to cover all price distress from these risks. At least there is plenty evidence to suggest that price distress is a norm in some of the projects that are delivered under traditional procurement. This paper will find the impact of construction risk factors into actual construction price into PPP projects. The paper will present a brief literature review on PPP risk pricing strategies, and then using system dynamics (SD) to analyses of the risks associated with the estimated project price. Based on the finding from these analyses a risk pricing association model is presented and discussed. The paper concludes with thoughts for future research.Keywords: Public Private Partnership (PPP), Risk, Risk Pricing, System Dynamics (SD), construction price
Procedia PDF Downloads 565