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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Cost Estimation Of Trackworks Of Light Rail And Metro Projects

Ozturk, Erhan 01 January 2009 (has links) (PDF)
The main objective of this work is to develop models using multivariable regression and artificial neural network approaches for cost estimation of the construction costs of trackworks of light rail transit and metro projects at the early stages of the construction process in Turkey. These two approaches were applied to a data set of 16 projects by using seventeen parameters available at the early design phase. According to the results of each method, regression analysis estimated the cost of testing samples with an error of 2.32%. On the other hand, artificial neural network estimated the cost with 5.76% error, which is slightly higher than the regression error. As a result, two successful cost estimation models have been developed within the scope of this study. These models can be beneficial while taking the decision in the tender phase of projects that includes trackworks.
42

Designing a cost estimation method for the design of prototype systems

Holmes, Jonathan Frank 09 April 2012 (has links)
There are unique cases when designing products where a prototype is required to demonstrate critical operations of a system or subsystem such that it will serve as a basis for how the design will move forward. These prototypes are oftentimes on the critical design path. Due to the fact there is typically some aspect of a prototype that is not well understood there can be a considerable amount of uncertainty associated with the amount of resources needed to design such a prototype. The goal of this thesis is to address how to systematically reduce uncertainty for the purpose of creating a robust cost estimate. This statement does highlight the problem of defining what a robust estimate is, which results in addressing the key question driving this research: "When is enough information gathered to generate a robust estimate for the design of prototype systems?" The crux of the problem lies in how to characterize the interactions and uncertainty associated with cost, schedule, and performance. Additionally, the breakdown of a prototype system into its subsystems results in errors exist at each division. The result is a cost estimation method that has been generated by leveraging the principles of design methodology. Two test cases are applied including one theoretical model, and one project from the Georgia Tech Research Institute (GTRI). The GTRI project was work performed for the Georgia Department of Transportation related to the filling of cracks on asphalt road surfaces. These examples are evaluated from the view point of the Validation Square in order to verify the effectiveness beyond example problems.
43

A cost-benefit forecasting framework for assessment of advanced manufacturing technology development

Jones, Mark Benjamin 05 1900 (has links)
Development of new Advanced Manufacturing Technology (AMT) for the aerospace industry is critical to enhance the manufacture and assembly of aerospace products. These novel AMTs require high development cost, specialist resource capabilities, have long development periods, high technological risks and lengthy payback durations. This forms an industry reluctance to fund the initial AMT development stages, impacting on their success within an ever increasingly competitive environment. Selection of suitable AMTs for development is typically performed by managers who make little reference to estimating the non-recurring development effort in resources and hardware cost. In addition, the performance at the conceptual stage is predicted using expert opinion, consisting of subjective and inaccurate outputs. AMTs selected are then submerged into development research and heavily invested in, with incorrect selections having a detrimental impact on the business. A detailed study of the UK aerospace manufacturing industry corroborated these findings and revealed a requirement for a new process map to resolve the problem of managing AMT developments at the conceptual stages. This process map defined the final research protocol, forming the requirement for a Cost-Benefit Forecasting Framework. The framework improves the decision making process to select the most suitable AMTs for development, from concept to full scale demonstration. Cost is the first element and is capable of estimating the AMT development effort in person-hours and cost of hardware using two parametric cost models. Benefit is the second element and forecasts the AMT tangible and intangible performance. The framework plots these quantified cost-benefit parameters and is capable of presenting development value advice for a diverse range of AMTs with varied applications. A detailed case study is presented evaluating a total of 23 novel aerospace AMTs verifying the capability and high accuracy of the framework within a large aerospace manufacturing organisation. Further validation is provided by quantifying the responses from 10 AMT development experts, after utilising the methodology within an industrial setting. The results show that quantifying the cost-benefit parameters provides manufacturing research and technology with the ability to select AMTs that provide the best value to a business.
44

A probabilistic pricing model for a company's projects / En probabilistisk prissättningsmodell för ett företags projekt

Malmquist, Daniel January 2012 (has links)
The company’s pricing is often highly impacted by the estimation of competitors’ project costs, which also is the main scope in this degree project. The purpose is to develop a pricing model dealing with uncertainties, since this is a main issue in the current pricing process. A pre-study has been performed, followed by a model implementation. An analysis of the model was then made, before conclusions were drawn. Project cost estimation foremost, but also probability distribution functions and pricing as a general concept, were investigated in the mainly literary pre-study. Two suitable methods for project cost estimation were identified; Monte Carlo simulation and Hierarchy Probability Cost Analysis. These lead to a theoretical project cost estimation model. A model was implemented in Matlab. It treats project cost estimation, but no other pricing aspects. The model was developed based on the theoretical one to the extent possible. Project costs were broken down in sub costs which were included in a Monte Carlo simulation. Competitors’ project costs were estimated using this technique. To analyse the model’s accuracy was difficult. It differs from the theoretical one in terms of how probability distribution functions and correlations are estimated. These problems depend on projects with shifting characteristics and limited data and time. A solid framework has been created though. Improvement possibilities exist, e.g. more accurate estimates and a model handling other pricing aspects. The major threat is that nobody maintains the model. Anyway, estimates are not more than just estimates. The model should therefore be viewed as a helpful tool, not an answer. / Företagets prissättning påverkas ofta till stor del av estimeringen av konkurrenters projektkostnader, vilket också är huvudområdet i detta examensarbete. Syftet är att utveckla en prissättningsmodell som hanterar osäkerheter, då detta är ett stort problem i rådande prissättningsprocess. En förstudie har utförts, följt av en modellimplementation. En analys av modellen gjordes sedan, innan slutsatser drogs. Projektkostnadsestimering främst, men även sannolikhetsfunktioner och prissättning som ett allmänt koncept, undersöktes i den i huvudsak litterära förstudien. Två lämpliga metoder för projektkostnadsestimering identifierades; Monte Carlo-simulering och Hierarchy Probability Cost Analysis. Dessa ledde till en teoretisk modell för projektkostnadsestimering. En modell implementerades i Matlab. Den behandlar projektkostnadsestimering, men inga andra prissättningsaspekter. Modellen utvecklades baserat på den teoretiska i möjlig utsträckning. Projektkostnader bröts ner i delkostnader som estimerades för konkurrenterna. Dessa ingick i en Monte Carlo-simulering. Konkurrenters projektkostnader estimerades med hjälp av denna teknik. Att analysera modellens noggrannhet var svårt. Den skiljer sig från den teoretiska beträffande hur sannolikhetsfunktioner och korrelationer estimeras. Dessa problem beror på projekt med skiftande karaktärsdrag samt begränsad data och tid. Ett solitt ramverk har dock skapats. Förbättringsmöjligheter finns, t.ex. noggrannare estimat och en modell som behandlar andra prissättningsaspekter. Det huvudsakliga hotet är att ingen underhåller modellen. Hur som helst är estimat inte mer än estimat. Modellen ska därför ses som ett hjälpverktyg, inte ett facit.
45

Costing for the Future: Exploring Cost Estimation with Unmanned Autonomous Systems

Ryan, Thomas Robert Jr. January 2015 (has links)
This thesis explores three topics in the field of cost estimation for Unmanned Autonomous Systems. First, we propose a common definition of an Unmanned Autonomous System. We accomplish this through exhausting the literature in the areas cost estimation, autonomy in its current form, and how such advanced systems might be integrated into their environment. Second, we introduce a method to estimate the cost of Unmanned Autonomous Systems utilizing existing parametric cost estimation tools: SEER–HDR, COCOMO II, COSYSMO, and two cost estimating relationships–weight and performance. This discussion is guided by focusing on how current tools attempt to account for emergent systems. We also attempt to address challenges surrounding autonomy. To address these challenges from a cost perspective, this thesis recommends modifications to parameters within COCOMO II–via the use of object-oriented function points in lieu of current methods, and COSYSMO–via the introduction of two cost drivers namely, TVED and HRI-T. Third, we conduct analysis on four current Army Unmanned Autonomous Systems in an attempt to establish early trends within existing estimates. Finally, we explore areas of further research and discuss the implications of how pursing a more adequate cost model will lead to a better understanding of this ill-defined paradigm. *This material is based upon work supported by the Naval Postgraduate School Acquisition Research Program under Grant No. N00244-15-1-0008. The views expressed in written materials or publications, and/or made by speakers, moderators, and presenters, do not necessarily reflect the official policies of the Naval Postgraduate School nor does mention of trade names, commercial practices, or organizations imply endorsement by the U.S. Government.
46

Μαθησιακά αντικείμενα : διαδικασίες επαναχρησιμοποίησης και εκτίμηση κόστους

Κωστόπουλος, Γεώργιος 06 November 2014 (has links)
Τις τελευταίες δεκαετίες παρατηρείται ραγδαία εξέλιξη των τεχνολογιών πληροφορικής και επικοινωνιών, ενώ συγχρόνως η διάθεση εκπαιδευτικού υλικού μέσω συστημάτων ηλεκτρονικής μάθησης αυξάνεται συνεχώς. Τα μαθησιακά αντικείμενα (ΜΑ) αποτελούν ένα νέο τρόπο προσέγγισης της οργάνωσης του εκπαιδευτικού περιεχομένου και βρίσκονται στον πυρήνα του νέου διδακτικού σχεδιασμού (Νικολόπουλος, Πιερρακέας, & Καμέας, 2011), αποτελώντας τη βάση για τη δημιουργία και το χειρισμό ψηφιακού εκπαιδευτικού περιεχομένου στην τεχνολογικά ενισχυμένη μάθηση (Sampson, & Zervas, 2011). Έχοντας μια σχετικά σύντομη ζωή στο χώρο της ηλεκτρονικής μάθησης, έχουν γίνει σήμερα ο επικρατέστερος ανάμεσα σε διάφορους άλλους όρους οι οποίοι προσπαθούν να περιγράψουν την ποικιλία των διαθέσιμων ψηφιακών πόρων που μπορούν να αξιοποιηθούν στην εκπαιδευτική διαδικασία (Βορβυλάς, 2013). Ο στόχος της συγκεκριμένης εργασίας είναι η μελέτη των ΜΑ, η αναλυτική περιγραφή των διαδικασιών επαναχρησιμοποίησης ΜΑ και η αξιολόγηση, μέσω χρήσης κατάλληλων μετρικών, του κόστους της επαναχρησιμοποίησης για τη δημιουργία μαθημάτων, ενοτήτων και προγραμμάτων σπουδών. Γνωστά στη διεθνή βιβλιογραφία ως αντικείμενα επικοινωνίας (Norton 1996), εκπαιδευτικά αντικείμενα (Friesen, 1996), επαναχρησιμοποιήσιμα αντικείμενα μάθησης (Barritt, Lewis and Wieseler 1999), γνωστικά αντικείμενα (Merrill, 1998), αντικείμενα πληροφοριών (Gibbons, Nelson, & Richards, 2000), διδακτικές μονάδες (Koper, 2001) κ.ά., τα ΜΑ έχουν εμφανισθεί τις δύο τελευταίες δεκαετίες και αποτελούν τη βάση για τη δημιουργία και το χειρισμό εκπαιδευτικού ψηφιακού περιεχομένου για τις ανάγκες της εκπαίδευσης, της μάθησης και της εξάσκησης των μαθητών. Ορισμοί έχουν δοθεί για τα ΜΑ, όπως για παράδειγμα από τον J. L’Allier (1997), το Institute of Electrical and Electronics Engineers (2000), τον David A. Wiley (2002), τους Rehak & Mason (2003), τον Polsani (2003), τον Andres Chiappe (2007), κ.ά. Παρόλα αυτά, οι προσπάθειες για την ανάπτυξη ή αποδοχή ενός κοινού εννοιολογικού ορισμού για τα ΜΑ από την εκπαιδευτική κοινότητα και τους εμπλεκόμενους φορείς, δεν έχουν καρποφορήσει. Εντούτοις, έχουν γίνει κοινά αποδεκτά κάποια λειτουργικά χαρακτηριστικά των ΜΑ, τα οποία σύμφωνα με τον Polsani (2003) είναι: • Προσβασιμότητα (Accessibility) • Επαναχρησιμοποίηση (Reusability) • Διαλειτουργικότητα (Interoperability) Ποικίλες θεωρήσεις κυριαρχούν αναφορικά με τη δομή και το μέγεθος ενός ΜΑ, η οποία πρέπει να περιλαμβάνει οπωσδήποτε την εκπαιδευτική προσέγγιση (ένα ΜΑ πρέπει να συνδέεται με έναν ή περισσότερους μαθησιακούς στόχους και πρέπει να υποστηρίζει την εκπαιδευτική διαδικασία (Νικολόπουλος κ.ά, 2011)), τις τεχνικές προδιαγραφές (μέγεθος-επίπεδο συνάθροισης), τα μεταδεδομένα, τον κύκλο ζωής, καθώς και την, βασισμένη σε κατάλληλες μετρικές, αξιολόγηση του κόστους επαναχρησιμοποίησής του. Θα μελετηθεί η διαδικασία επαναχρησιμοποίησης ΜΑ, η οποία αποτελεί ένα από τα βασικά χαρακτηριστικά των ΜΑ. Η βασική ιδέα αφορά στη χρήση μικρών, διακριτών ΜΑ ή/και το συνδυασμό τους για τη δημιουργία νέων, τα οποία να αποτελούν ένα ενιαίο εκπαιδευτικό σενάριο που να μπορεί να λειτουργήσει σε διαφορετικά εκπαιδευτικά πλαίσια, καθώς και σε διαφορετικά άτομα. Από τη μια, ένα σημαντικό πλεονέκτημα που συνεπάγεται η επαναχρησιμοποίηση ενός ΜΑ είναι η σημαντική μείωση του κόστους σχεδιασμού και ανάπτυξης των απαιτούμενων πόρων, διατηρώντας παράλληλα την ποιότητα, και από την άλλη μπορεί να αποτελέσει ένα δείκτη της υψηλής ποιότητας των διαθέσιμων ΜΑ, με την παραδοχή ότι όσο περισσότερο επαναχρησιμοποιείται ένα ΜΑ, τόσο μεγαλύτερη θα είναι η ποιότητά του (Sampson, & Zervas, 2011). Εντούτοις, υπάρχουν και μειονεκτήματα από την επαναχρησιμοποίηση ΜΑ. Το βασικότερο είναι ότι μερικές φορές το κόστος της επαναχρησιμοποίησης μπορεί να είναι μεγαλύτερο από το κόστος για τη δημιουργία νέων ΜΑ. Επίσης, πολλές φορές δεν είναι εύκολο να εμπιστευτεί κάποιος την ποιότητα των συστατικών μερών ΜΑ, τα οποία έχουν δημιουργηθεί από άλλους. Έτσι, δύσκολα είναι άμεσα μετρήσιμη η μείωση του κόστους και άρα το όφελος που προκύπτει κατά την επαναχρησιμοποίηση, κατά συνέπεια πολλές φορές συμφέρει η δημιουργία νέων ΜΑ από την επαναχρησιμοποίηση υφιστάμενων ΜΑ (Sommerville, 2006). Παρά τη σπουδαιότητα της έννοιας της επαναχρησιμοποίησης ΜΑ δεν υπάρχει κάποιος απλός τρόπος επακριβούς μέτρησης του κόστους-οφέλους που μπορεί να έχουμε σε αυτή τη διαδικασία. Η ύπαρξη μετρικών για την εκτίμηση του κόστους αποδοτικής επαναχρησιμοποίησης εκπαιδευτικών ΜΑ είναι δυνατό να διευκολύνει στον τομέα της συστηματικής αξιολόγησής τους και να δώσουν απάντηση στο ερώτημα: «Πότε αξίζει τον κόπο να επαναχρησιμοποιήσουμε και να ενσωματώσουμε ΜΑ ώστε να δημιουργήσουμε νέα;». Έτσι τελικά, θα γίνει μια μελέτη εντοπισμού και προσαρμογής μετρικών που σχετίζονται με τον τομέα της τεχνολογίας λογισμικού για την εκτίμηση του κόστους δημιουργίας εκπαιδευτικών σεναρίων και γενικότερα εκπαιδευτικού λογισμικού με επαναχρησιμοποίηση ΜΑ. Συνδέοντας αυτές τις μετρικές άμεσα με τα διάφορα στάδια του κύκλου ζωής των ΜΑ, είναι δυνατή η τελική εκτίμηση του κόστους επαναχρησιμοποίησης τους. Αυτό θα μπορούσε να δώσει τη δυνατότητα σε εκπαιδευτικούς, ιδρύματα και οργανισμούς να αξιολογήσουν αποτελεσματικά τη δημιουργία εκπαιδευτικών σεναρίων και εκπαιδευτικού λογισμικού με επαναχρησιμοποιήσιμα ΜΑ, καθώς και τη βελτίωσή τους (Sampson, & Zervas, 2011). / Over the last decades a rapid development of information technologies and communications in education is observed, while simultaneously the disposal of educational material through systems of e-learning is increasing continuously. Learning objects (LOs) constitute a new way of approaching the systematization of instructional content and are found in the core of a new educational development, constituting the base for the creation and the handling of digital educational content in technology-enhanced learning. Having a relatively short life in the area of e-learning, they have become today the most prevalent between various other terms that try to describe the variety of available digital resources that can be developed in the didactic processes. In this work, our basic goal is the study of LOs, the comprehensive description of LOs reuse processes and the evaluation of LOs reuse cost for the development of lessons, units and courses using appropriate metrics. Mostly known in the academic bibliography as media objects (Norton, 1996), educational objects (Friesen, 1996), reusable learning objects (Barritt, Lewis and Wieseler, 1999), knowledge objects (Merrill, 1998), data objects (Gibbons, Nelson, & Richards, 2000), instructional objects (Gibbons et al., 2000) or units of learning (Koper, 2001), LOs have appeared over the last decades and constitute the base for the creation and the handling of educational digital content for the needs of education, learning and students practice. Various definitions have been given for the LOs, for example from the J. L' Allier (1997), the Institute of Electrical and Electronics Engineers (2000), David A. Wiley (2002), Rehak and Mason (2003), Polsani (2003), Andres Chiappe (2007). All efforts for the development or recognition of a common conceptual definition of LOs by the educational community and the involved institutions have not thrived. However, there is a broad understanding among the members of the LO community about the functional requirements of LOs: • Accessibility • Reusability • Interoperability Various endorsements refer to the structure and the size of a LO, which should include the instructional approach (a LO should be based on one or more learning objectives and should support the educational processes), the technical specifications (level of aggregation), the metadata records, the lifecycle and the evaluation of LOs cost effective reuse that is based in suitable metrics. We will study the processes of LOs reuse, which is one of the basic characteristics of LOs. The basic idea concerns in the use of small and distinguishable LOs and/or their combination for the creation of new LOs which constitute a single educational script that could function in different educational frames as well as in different individuals. From the one hand, an important advantage that involves the re-use of MA is the important reduction of cost of planning and growth of required resources, maintaining at the same time the quality, and from the other hand, LO reuse can be an indicator for a high quality LO, under the assumption that the more a LO is reused the more likely is to be of a high quality. However, there are also disadvantages from LOs reuse. The most critical is that sometimes the cost of LO reuse can be larger than the cost of the creation of new one. Also, it is not often easy for a teacher to trust the quality of an existing LO which has been created by others. Thus, it is very difficult to measure the reduction of cost and hence the profit that results from the reuse. As an effect, many times it is easier to create new LOs than reuse existing LOs. Despite the importance of LOs reuse, there does not exist a simple way of precise measurement of the cost effectiveness in this process. The existence metrics for the estimation of the cost effectiveness of LOs reuse is possible to facilitate in the sector of their systematic evaluation and give an answer in the question: “When is it worth to reuse and incorporate existing LOs in order to create new?” Therefore, we will make a study of identification and adaptation of metrics that are related to the sector of software engineering in order to estimate the cost of creation instructional scripts and generally educational software with reusing LOs. Relating these metrics with the various stages of LOs lifecycle the final estimation of their cost reuse will be possible. This could give the chance to teachers, schools and organisms of evaluating effectively the creation and improvement of educational scripts and instructional software using reusable LOs.
47

Išorės ir vidaus apdailos darbų automatizuotų sąmatinių skaičiavimų ir ekonominių resursų poreikio analizė / The analysis of automated estimate calculations and resources requerements for works of internal and external finishing

Sodeika, Mantas 13 June 2005 (has links)
This work deals with the computer aided design technology based on the concept of static graphical – information modeling, which has the following goal: to ensure the succession of the building design, its construction process and project maintenance management; to ensure the integrated management of graphical and information data flows under a unified software environment; to perform life cycle operations of a construction project better, cheaper, and faster. State-of-the-art automated design, to be more specific, computer aided design is based on Object Modeling Technique (OM): “from idea to a real object”. One of the fundamental innovations of this technology includes component modeling. While implementing this design the concept of the relation between a graphical – information model of a building and estimate calculations has been formulated; technique for classifying design elements and materials has been generated; necessary programming tools and data structures have been developed; integration of CAD OM and EP systems has been performed; technique for computer aided evaluation of economic indicators of a construction project has been composed, enabling to price a project interactively. For effective design, technological and organizational variants of construction finishing the proposed TOPSIS method has been selected.
48

A Decision Support System For Production Planning And Pre-cost Estimation Activities In An Apparel Company

Gokalp, Ebru 01 July 2010 (has links) (PDF)
In this study, a specific decision support system is designed and developed for Production Planning and Marketing Department of an apparel company. The developed system involves two modules with user friendly interface or data input and query. The system is designed to provide support in the following fields of decision making / pre cost estimation, capacity planning, master production planning and production scheduling. A detailed analysis of the existing system is conducted and Microsoft Access is used for the development of software. The cost and benefits of the implementing the system are also discussed in addition to basics, sample reports and the user interface of the developed program.
49

Analyzing the Distribution and Variations in Construction Costs for Commercial Tenant Improvement Projects

January 2016 (has links)
abstract: In this era of high-tech computer advancements and tremendous programmable computer capabilities, construction cost estimation still remains a knowledge-intensive and experience driven task. High reliance on human expertise, and less accuracy in the decision support tools render cost estimation error prone. Arriving at accurate cost estimates is of paramount importance because it forms the basis of most of the financial, design, and executive decisions concerning the project at subsequent stages. As its unique contribution to the body of knowledge, this paper analyzes the deviations and behavior of costs associated with different construction activities involved in commercial office tenant improvement (TI) projects. The aim of this study is to obtain useful micro-level cost information of various construction activities that make up for the total construction cost of projects. Standardization and classification of construction activities have been carried out based on Construction Specifications Institute’s (CSI) MasterFormat® division items. Construction costs from 51 office TI projects completed during 2015 and 2016 are analyzed statistically to understand the trends among various construction activities involved. It was found that the interior finishes activities showed a much higher cost of construction, and a comparatively higher variation than the mechanical, electrical, and plumbing (MEP) trades. The statistical analysis also revealed a huge scope of energy saving measures that could be achieved in such TI projects because of the absence of energy management systems (EMS) found in 66% of the projects. / Dissertation/Thesis / Masters Thesis Construction 2016
50

Otimizacao da etapa de armazenamento de rejeitos radioativos

DELLAMANO, JOSE C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:31Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:16Z (GMT). No. of bitstreams: 1 10380.pdf: 7268074 bytes, checksum: fcb1abf468040268c71659acc3619d8d (MD5) / Tese (Doutoramento) / IPEN/T / Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP

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