Building Strategy and Performance Through Time: The Critical Path

2009 ◽  
Keyword(s):  
Critical Path ◽  
And Performance

scholarly journals Moving towards a reliable HIV incidence test – current status, resources available, future directions and challenges ahead

2016 ◽  
Vol 145 (5) ◽  
pp. 925-941 ◽  
Author(s):  
G. MURPHY ◽  
C. D. PILCHER ◽  
S. M. KEATING ◽  
R. KASSANJEE ◽  
S. N. FACENTE ◽  
...  
Keyword(s):  
Performance Metrics ◽  
Critical Path ◽  
Population Level ◽  
Current Status ◽  
Hiv Incidence ◽  
Recent Infection ◽  
Novel Approach ◽  
Product Profile ◽  
And Performance ◽  
The Impact

SUMMARYIn 2011 the Incidence Assay Critical Path Working Group reviewed the current state of HIV incidence assays and helped to determine a critical path to the introduction of an HIV incidence assay. At that time the Consortium for Evaluation and Performance of HIV Incidence Assays (CEPHIA) was formed to spur progress and raise standards among assay developers, scientists and laboratories involved in HIV incidence measurement and to structure and conduct a direct independent comparative evaluation of the performance of 10 existing HIV incidence assays, to be considered singly and in combinations as recent infection test algorithms. In this paper we report on a new framework for HIV incidence assay evaluation that has emerged from this effort over the past 5 years, which includes a preliminary target product profile for an incidence assay, a consensus around key performance metrics along with analytical tools and deployment of a standardized approach for incidence assay evaluation. The specimen panels for this evaluation have been collected in large volumes, characterized using a novel approach for infection dating rules and assembled into panels designed to assess the impact of important sources of measurement error with incidence assays such as viral subtype, elite host control of viraemia and antiretroviral treatment. We present the specific rationale for several of these innovations, and discuss important resources for assay developers and researchers that have recently become available. Finally, we summarize the key remaining steps on the path to development and implementation of reliable assays for monitoring HIV incidence at a population level.

Designer Solid Shims for Assembly of Advanced Carbon Composite Pre-preg based Aircraft Structures

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Sanjay Kumar ◽  
P. Selvaraj
Keyword(s):  
Composite Structure ◽  
Delta Wing ◽  
Critical Path ◽  
Research Work ◽  
Carbon Composite ◽  
Raw Material ◽  
Manufacturing Cost ◽  
Interface Surface ◽  
Combat Aircraft ◽  
And Performance

A modern combat aircraft uses considerable amount of advanced composite material in structure build for better flight performance, stealth requirement and higher payload. Combat aircrafts made using composite structure require large numbers of custom shims of various thickness and shapes throughout interface surface, which are presently prepared by suit on assembly process to fill gaps measured between sub-structure parts and skin. The scope of study is four plus generation combat aircraft like Indian Light combat aircraft. These gaps arise due to composite raw material characteristics, mould tool and manufacturing process which results in geometry variation. This research has focussed the delta wing integral fuel tank composite structure. However, these research findings can be applied in other wing shapes made by composite part within the scope. The shims, whether liquid or solid, are necessary to eliminate gaps, maintain structural performance and minimize pull-down forces required to bring the aircraft into engineering nominal configuration for aerodynamic efficiency. Customized shims amount to significant delays in production with much of the time being spent in the critical path of the aircraft assembly. In this research work, we present an alternative strategy for the use of designer solid shim, based on redesign of lay-up moulding tool (female type) and shims manufacturing with change in existing manufacturing value stream. The experimented method has reduced the manufacturing cost of wing assembly, shorten the shimming process cycle and improve the assembly efficiency, product quality and performance.

scholarly journals Power and Area Efficient Clock Stretching and Critical Path Reshaping for Error Resilience

2019 ◽  
Vol 9 (1) ◽  
pp. 5
Author(s):  
Mini Jayakrishnan ◽  
Alan Chang ◽  
Tony Tae-Hyoung Kim
Keyword(s):  
Critical Path ◽  
Error Resilience ◽  
Cost Effective ◽  
Advanced Technology ◽  
Worst Case ◽  
Flip Flop ◽  
Smart Products ◽  
Run Time ◽  
Critical Paths ◽  
And Performance

Energy efficient semiconductor chips are in high demand to cater the needs of today’s smart products. Advanced technology nodes insert high design margins to deal with rising variations at the cost of power, area and performance. Existing run time resilience techniques are not cost effective due to the additional circuits involved. In this paper, we propose a design time resilience technique using a clock stretched flip-flop to redistribute the available slack in the processor pipeline to the critical paths. We use the opportunistic slack to redesign the critical fan in logic using logic reshaping, better than worst case sigma corner libraries and multi-bit flip-flops to achieve power and area savings. Experimental results prove that we can tune the logic and the library to get significant power and area savings of 69% and 15% in the execute pipeline stage of the processor compared to the traditional worst-case design. Whereas, existing run time resilience hardware results in 36% and 2% power and area overhead respectively.

scholarly journals Design, analysis and performance evaluation of parallel algorithms for solving triangular linear systems on multicore platforms

2021 ◽  
Author(s):  
Mounir Marrakchi ◽  
Mounira Belmabrouk
Keyword(s):  
Performance Evaluation ◽  
Integer Programming ◽  
Lower Bound ◽  
Linear System ◽  
Linear Algebra ◽  
Critical Path ◽  
Mixed Integer ◽  
The Third ◽  
Integer Problem ◽  
And Performance

In this paper, we focus on schedulings of 2-steps graph with constant task cost obtained when parallelizing algorithm solving triangular linear system. We present three scheduling approaches having the same least theoretical execution time. The first is designed through solving a 0-1 integer problem by Mixed Integer Programming (MIP), the second is based on the Critical Path Algorithm (CPA) and the third is a particular Column-Oriented Scheduling (COS). The MIP approach experiments were carried out and confirmed that the makespan values of the MIP scheduling coincide with those of the corresponding lower bound already reached. Experimental results of the last two approaches detailing both makespans and efficiencies are presented and show that their practical performances differ though they are theoretically identical. We compare also these results to those of the appropriate procedure in to so-called PLASMA library (Parallel Linear Algebra for Scalable Multi-core Architectures)

scholarly journals A NEW ANALYTICAL METHODOLOGY TO HANDLE TIME-COST TRADE-OFF PROBLEM WITH CONSIDERING QUALITY LOSS COST UNDER INTERVAL-VALUED FUZZY UNCERTAINTY

2019 ◽  
Vol 25 (2) ◽  
pp. 277-299 ◽  
Author(s):  
Mohammad Hossein Haghighi ◽  
Seyed Meysam Mousavi ◽  
Jurgita Antuchevičienė ◽  
Vahid Mohagheghi
Keyword(s):  
Critical Path ◽  
Quality Loss ◽  
Time Cost ◽  
Analytical Methodology ◽  
New Approach ◽  
Trade Off ◽  
Trade Offs ◽  
And Performance ◽  
Interval Valued

This paper proposes a new framework in addressing time-cost trade-off problem (TCTP) under uncertainty. First critical path analysis is carried out based on developing a new interval-valued fuzzy (IVF)-program evaluation and review technique (PERT) approach. Then, non-conformance risks that influence on execution quality of activities are identified and evaluated based on a new approach that considers probability of risk along with impacts on time, cost, and performance. Then, a new mathematical model under IVF uncertainty is presented to decrease project total time while considering time, cost and quality loss cost that is determined in form of rework or modification cost. Finally, the approach categorizes the activities in three groups based on their level of criticality. Outcome of this methodology is a scheduling that addresses time, cost and quality trade-offs in addition to categorizing activities in different groups based on being on the critical path. Therefore, the project manager not only gets a scheduling based on the TCTP with considering quality loss cost but also has a knowledge of activities that require extra attentions. To show the steps of this methodology, an existing application from the literature is adopted and solved.

Pressurizer Safety Valve Data Collection, Analysis, and Performance

2016 ◽  
Author(s):  
T. Esselman ◽  
G. Zysk ◽  
P. Streeter ◽  
B. Elaidi ◽  
H. Garcia ◽  
...  
Keyword(s):  
Safety Valve ◽  
Critical Path ◽  
Operating Conditions ◽  
Inlet Pipe ◽  
Data Analyses ◽  
Thermal Growth ◽  
Start Up ◽  
Pressurization Rate ◽  
And Performance ◽  
Water Seal

The Pressurizer Safety Valves (PSVs) at Diablo Canyon Power Plant were manufactured by Crosby and are model 6M6 HB-86-BP valves. The valves have intermittingly experienced leakage as the units are heated up and pressurized to normal operating conditions. When leakage occurs, a time-consuming de-pressurization and re-pressurization process is implemented that causes significant delays in the return to power after an outage. Following the elimination of the upstream water seal, leakage has occurred on individual valves during all but one start-up. After recent PSV leakage, instrumentation was installed to obtain information during the subsequent unit heat up and pressurization. The instruments included thermocouples on the inlet pipe, the discharge pipe, and the valve. Data was collected during a unit start-up in which two of the three installed valves leaked. Piping and valve analyses were performed using the data to modify the valve installation procedures, to modify the process for accommodating piping thermal growth, and to modify the pressurization rate during start-up. Upon implementation of these changes, none of the PSVs leaked during the subsequent unit heat up and pressurization, saving more than 24 critical path hours. The data, analyses, and modifications will be described along with the analyses used to support an increase in the pressurization rate for unit start-up.

Project scheduling and performance prediction: a fuzzy-Bayesian network approach

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Pejman Rezakhani
Keyword(s):  
Bayesian Network ◽  
Project Scheduling ◽  
Critical Path ◽  
Project Managers ◽  
Process Time ◽  
Project Schedule ◽  
Activity Data ◽  
Content Type ◽  
Unknown Risk ◽  
And Performance

PurposeDespite the extensive research in project risk management and availability of several techniques and tools, quantifying uncertainty in project schedules remains a challenge. Current risk analysis models suffer from several shortcomings that need to be addressed to provide more reliable and valid schedules. This paper aims to present a dynamic decision support system with the purpose of providing project managers with necessary tool for making real-time informed decisions.Design/methodology/approachThe proposed approach incorporates the widely accepted critical path method (CPM) calculations in a Bayesian network (BN). BN is employed to conduct inferencing and causal analysis and provide probabilistic results, which can improve the decision-making process. Time parameters of each activity in the CPM network is modeled by a set of simulation nodes in the BN. Prior probability distribution of activities duration is extracted from experts using a fuzzy analytical solution.FindingsThe model proposed in this paper is able to address some key outstanding issues of current project scheduling techniques through: (1) modeling the causality among different sources of schedule uncertainty, (2) minimizing uncertainty in experts' evaluations, (3) assessing effects of unknown risk factors and (4) using actual activity data for learning the behavior of project and predicting crew productivity.Originality/valueThe purposed methodology provides a framework for the new generation of project schedule analysis tools that are better informed by available knowledge and data, and hence, more reliable and useful.

scholarly journals Critical path-driven property and performance transitions in heterogeneous microstructures

2017 ◽  
Vol 52 (9) ◽  
pp. 4796-4809 ◽  
Author(s):  
Kenneth Reifsnider ◽  
Fazle Rabbi ◽  
Vamsee Vadlamudi ◽  
Rassel Raihan ◽  
Kyle Brinkman
Keyword(s):  
Critical Path ◽  
Heterogeneous Microstructures ◽  
And Performance

Transmission Scanning Electron Microscopy and Energy Analysis with the Siemens ELMISKOP 101

1972 ◽  
Vol 30 ◽  
pp. 450-451
Author(s):  
H. M. Thieringer
Keyword(s):  
Objective Lens ◽  
Transmission Microscopy ◽  
Image Recording ◽  
Mode Of Operation ◽  
Scanning Transmission ◽  
Electron Microscopes ◽  
And Performance ◽  
Convergent Beam ◽  
Ray Path ◽  
Beam Diffraction

It has repeatedly been show that with conventional electron microscopes very fine electron probes can be produced, therefore allowing various micro-techniques such as micro recording, X-ray microanalysis and convergent beam diffraction. In this paper the function and performance of an SIEMENS ELMISKOP 101 used as a scanning transmission microscope (STEM) is described. This mode of operation has some advantages over the conventional transmission microscopy (CTEM) especially for the observation of thick specimen, in spite of somewhat longer image recording times.Fig.1 shows schematically the ray path and the additional electronics of an ELMISKOP 101 working as a STEM. With a point-cathode, and using condensor I and the objective lens as a demagnifying system, an electron probe with a half-width ob about 25 Å and a typical current of 5.10-11 amp at 100 kV can be obtained in the back focal plane of the objective lens.

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