The cost performance of transportation projects: The fallacy of the Planning Fallacy account

2019 ◽  
Vol 122 ◽  
pp. 1-20 ◽  
Author(s):  
Peter E.D. Love ◽  
Michael C.P. Sing ◽  
Lavagnon A. Ika ◽  
Sidney Newton
Keyword(s):  
Cost Performance ◽  
Transportation Projects ◽  
Planning Fallacy ◽  
The Cost

scholarly journals Roughing Milling with Ceramic Tools in Comparison with Sintered Carbide on Nickel-Based Alloys

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 734
Author(s):  
Pablo Fernández-Lucio ◽  
Octavio Pereira Neto ◽  
Gaizka Gómez-Escudero ◽  
Francisco Javier Amigo Fuertes ◽  
Asier Fernández Valdivielso ◽  
...  
Keyword(s):  
Cutting Speed ◽  
High Volume ◽  
Cemented Carbide ◽  
Performance Ratio ◽  
Cost Performance ◽  
Ceramic Tools ◽  
The Cost ◽  
Engine Components ◽  
Coated Carbide ◽  
Milling Tools

Productivity in the manufacture of aircrafts components, especially engine components, must increase along with more sustainable conditions. Regarding machining, a solution is proposed to increase the cutting speed, but engines are made with very difficult-to-cut alloys. In this work, a comparison between two cutting tool materials, namely (a) cemented carbide and (b) SiAlON ceramics, for milling rough operations in Inconel® 718 in aged condition was carried out. Furthermore, both the influence of coatings in cemented carbide milling tools and the cutting speed in the ceramic tools were analysed. All tools were tested until the end of their useful life. The cost performance ratio was used to compare the productivity of the tested tools. Despite the results showing higher durability of the coated carbide tool, the ceramic tools presented a better behavior in terms of productivity at higher speed. Therefore, ceramic tools should be used for higher productivity demands, while coated carbide tools for low speed-high volume material removal.

A weak derivative approach to optimization of threshold parameters in a multicomponent maintenance system

2001 ◽  
Vol 38 (02) ◽  
pp. 386-406 ◽  
Author(s):  
Bernd Heidergott
Keyword(s):  
Optimization Problems ◽  
Estimation Algorithm ◽  
Replacement Policy ◽  
Cost Performance ◽  
Weak Derivative ◽  
Preventive Replacement ◽  
Maintenance System ◽  
Threshold Optimization ◽  
Age Replacement ◽  
The Cost

We consider a multicomponent maintenance system controlled by an age replacement policy: when one of the components fails, it is immediately replaced; all components older than a threshold age θ are preventively replaced. Costs are associated with each maintenance action, such as replacement after failure or preventive replacement. We derive a weak derivative estimator for the derivative of the cost performance with respect to θ. The technique is quite general and can be applied to many other threshold optimization problems in maintenance. The estimator is easy to implement and considerably increases the efficiency of a Robbins-Monro type of stochastic approximation algorithm. The paper is self-contained in the sense that it includes a proof of the correctness of the weak derivative estimation algorithm.

scholarly journals The increased use value of bamboo leaves as silica source for t-type zeolite synthesis

2018 ◽  
Vol 197 ◽  
pp. 05003 ◽  
Author(s):  
Soni Setiadji ◽  
Citra Deliana Dewi Sundari ◽  
Endang Lala ◽  
Denia Febby Nurbaeti ◽  
Ira Novianti ◽  
...  
Keyword(s):  
Sem Analysis ◽  
High Price ◽  
Heating Process ◽  
Zeolite Synthesis ◽  
X Ray Diffraction ◽  
Cost Performance ◽  
Silica Source ◽  
Bamboo Leaves ◽  
Type Zeolite ◽  
The Cost

T-type zeolite can be used as catalyst, adsorbent, and membranes for gas separation. The synthesis of T-type zeolite needs to be optimized in both of the method and source of precursor, because of its relatively high price. In this research, the synthesis is done using silica extracted from bamboo leaves instead of commercial silica. This increases the value of the bamboo leaves and the cost-performance of zeolite synthesis. The silica was extracted from bamboo leaves ash using alkaline solvent. The extracted silica has 81.76% of purity and an amorphous phase. The T-type zeolite was synthesized using the molar composition of 0.15 Na2O : 0.025 Al : 0.15 K2O : 1 SiO2 : 15 H2O : 0.06 TMAOH, under hydrothermal method and heating process for 4 days, 60°C for 2 days and 120°C for the next 2 days. The characterization method using X-Ray Diffraction and Infra-Red Spectroscopy were performed to confirm the formation of T-type zeolite. The results of Scanning Electron Microscope (SEM) analysis show that the formed T-type zeolite has erionite cylindrical crystal shape.

scholarly journals Cost and Efficiency Analysis of Commercial Softeners in the Sewability Behavior of Cotton Fabrics

2015 ◽  
Vol 10 (2) ◽  
pp. 155892501501000 ◽  
Author(s):  
Cândida Vidrago ◽  
Maria José Araújo Marques Abreu ◽  
Graça Soares ◽  
Helder Carvalho
Keyword(s):  
Efficiency Analysis ◽  
Cotton Fabrics ◽  
Comparative Case Study ◽  
Cost Performance ◽  
Micro Emulsion ◽  
The Cost ◽  
The Relationship ◽  
Performance Behavior

This paper reports a comparative case study on the use of different softening products for bed linen fabrics, specifically regarding the sewability of the fabrics. The market offers a wide variety of commercial formulations of softeners for this purpose, but the composition and price varies considerably. This work was aimed to assess the relationship between the cost and effectiveness of different softener formulations in home textiles finishing. Objectively, the effect of different softeners and their concentrations on sewability of the fabrics was studied. Non-ionic polyethylene dispersions and a cationic silicone softener micro-emulsion in different concentrations and combinations were considered in this investigation. It was found that a combination of silicone and polyethylene based softeners presents the most interesting cost/performance behavior.

Mitigating the legal challenges of imposing disincentives on nonperforming transportation projects

2020 ◽  
Vol 27 (10) ◽  
pp. 2859-2891
Author(s):  
Douglas Alleman ◽  
Eul-Bum Lee
Keyword(s):  
Case Studies ◽  
Subject Matter Experts ◽  
Pavement Rehabilitation ◽  
Content Type ◽  
Transportation Projects ◽  
Legal Challenges ◽  
Liquidated Damages ◽  
Valuation Process ◽  
The Cost ◽  
Transportation Agencies

PurposeThe publication presents an analysis of the cost and schedule performance of incentive/disincentive projects and case studies toward developing a systematic disincentive valuation process, with Construction Analysis for Pavement Rehabilitation Strategies (CA4PRS) software integration that aids agencies in minimizing the likelihood of court challenges of disincentives.Design/methodology/approachFrom a California transportation database, the authors performed cost and schedule analyses of 43 incentive/disincentive (I/D) projects and case studies on four of those I/D projects. Interviewees included subject matter experts from transportation organizations to ensure applicability and maximum value-adding, and the process was implemented on ten California transportation projects and monitored for performance.FindingsThe presented process mitigates the contractor's ability to claim disincentives as penalties in a court of law through the following: (1) all calculations are performed using project-specific bases, backed by estimations of actual incurred costs; (2) the CA4PRS software allows for estimation transparency and (3) the clarity of cost inclusions reduces any chances of “double-dipping” between disincentives and liquidated damages.Practical implicationsTransportation agencies have historically faced legal challenges to their enforcements of disincentives. As agencies continue to apply disincentives on more megaprojects, contractors will likely attempt to pursue legal challenges more frequently. The presented process mitigates the likelihood of these challenges going to court and increases the accuracy and efficiency of disincentives.Originality/valueWhile there have been publications that discuss the legal challenges of imposing disincentives, they mainly provide guidelines and lack applicable processes. Existing literature that does present incentive/disincentive valuation process focuses on incentive valuations and neglects the disincentives' legal challenges. The following publication fills this gap by presenting an applicable disincentive valuation process for transportation projects which incorporates the guidelines for legal mitigation.

Material Science and the Electronic Packaging Roadmap

1995 ◽  
Vol 390 ◽  
Author(s):  
C. A. Steidel ◽  
R. C. Sundahl ◽  
N. Grayeli
Keyword(s):  
Electronic Packaging ◽  
Material Science ◽  
Cost Performance ◽  
Significant Lowering ◽  
Silicon Devices ◽  
Technology Roadmap ◽  
And Performance ◽  
The Cost ◽  
National Technology

The National Technology Roadmap forecasts significant increases in performance for silicon devices over the next several years continuing the pace of the last 25 years. As the complexity and performance of the silicon have increased, so has the cost to manufacture the supporting packages. However, continued growth of the industry demands that package costs be held under control. A requirement of the Roadmap is a need for a significant lowering of cost over the period. On a per lead basis: for example, for cost/performance products in 1995 the range in per pin cost is 1.4–8 cents. These costs must move to 1–3 cents per lead over the next 15 years, while lead count increases from a few hundred to a few thousand. These costs will not be achievable unless we change how materials are developed and deployed to the market.

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