scholarly journals Analysis of production resources improvement strategies in make-to-stock environments managed by the simplified drum-buffer-rope system

2021 ◽  
Vol 28 (4) ◽  
Author(s):  
Humberto Govoni ◽  
Fernando Bernardi de Souza ◽  
Robson Flávio Castro ◽  
José de Souza Rodrigues ◽  
Silvio Roberto Ignacio Pires
Keyword(s):  
Continuous Improvement ◽  
Superior Performance ◽  
Theory Of Constraints ◽  
Single Constraint ◽  
Overall Performance ◽  
Make To Stock ◽  
Capacity Constrained ◽  
Performance Gains ◽  
Rope System ◽  
Production Resources

Abstract: Theory of Constraints (TOC) states that every system has a single constraint that limits its performance, on which improvement efforts should be concentrated. This paper compared, through computer simulation, several methods of identifying the capacity-constrained resource in the perspective of a process of continuous improvement. Six make-to-stock (MTS) production line configurations managed by the Simplified Drum-Buffer-Rope (S-DBR) system were simulated, in which six improvement methods were applied, three of them based on the TOC literature, and their performance measured and compared in terms of cycle time and order fill rate. The results showed that, in balanced systems, improvements spread over all resources allowed better results, because, in this case, it is necessary to improve everything to benefit the overall performance. In unbalanced environments, on the other hand, the three methods recommended by TOC, which recommend efforts concentrated on the weakest point of the system, achieved superior performance, with emphasis on the strategy based on the level of utilization. In addition to advancing the frontiers of knowledge in continuous improvement and TOC, the research results show that managers should focus their attention on the resource with the highest degree of utilization to get better and faster performance gains.

scholarly journals Computational study of multiple flapping hydrofoils for thrust production

2021 ◽  
Vol 347 ◽  
pp. 00021
Author(s):  
Uma Krige ◽  
Kim Boon Lua ◽  
Wei Hua Ho
Keyword(s):  
Reynolds Number ◽  
Computational Study ◽  
Optimal Number ◽  
Superior Performance ◽  
Optimal Conditions ◽  
Overall Performance ◽  
Thrust Production

Previous investigations of flapping hydrofoils for the purpose of thrust production have been limited to one or two in tandem. Tandem foils were found to have superior performance because the performance of the aft foil was augmented by the vortices shed from the fore foil. It is however not clear if increasing the number of foils will continue to have increased performance or if there exist an optimal number after which the overall performance either stagnates or reduces. A 2D computational study was conducted to investigate the effect of increasing the number of hydrofoils to four at a Reynolds number of 8000 flapping in-phase and out-of-phase. Optimal and sub-optimal conditions found previously with tandem hydrofoils were found also be applicable to three and four hydrofoils.

scholarly journals Assessment of Performance Enhancement Potential of a High-Temperature Parabolic Trough Collector System Combining the Optimized IR-Reflectors

2020 ◽  
Vol 10 (11) ◽  
pp. 3744 ◽  
Author(s):  
Qiliang Wang ◽  
Hongxing Yang ◽  
Gang Pei ◽  
Honglun Yang ◽  
Jingyu Cao ◽  
...  
Keyword(s):  
Heat Loss ◽  
Solar Irradiance ◽  
Superior Performance ◽  
Cutoff Wavelength ◽  
The Novel ◽  
Parabolic Trough ◽  
Optimal Cutoff ◽  
Parabolic Trough Collector ◽  
Photothermal Conversion ◽  
Overall Performance

Heat collecting elements (HCEs) are the core components in the parabolic trough collector (PTC) system because photothermal conversion of the whole system occurs in the HCEs. However, considerable heat loss from the HCEs at high operating temperature exerts seriously negative impact on the photothermal conversion efficiency of the PTC system and subsequent application systems. To effectively reduce the heat loss and thus enhance the overall performance of the PTC system, in our previous work, we proposed three kinds of novel HCEs by partially depositing different IR-reflector coatings on the inner and outer surfaces of the glass envelope. The infrared (IR)-reflector of actual transparent conductive oxide (TCO) film, IR-reflector with a fixed cutoff wavelength of 2.5 μm, and the IR-reflector with optimal cutoff wavelength showed extremely effective roles in the reduction of heat loss in HCEs. In this paper, the comprehensive energy and exergy performances of these three novel HCEs in a real 72 m small-scale PTC system are further investigated by the mathematical models established. Additionally, the comparisons among overall performances of the proposed HCEs under different direct solar irradiances are also carried out. The results show that the simulated data yields good consistence with the experimental results, and that all three of the novel HCEs achieve superior overall performance compared with the conventional HCEs. The PTC system installing the novel HCEs with the IR-reflector coating which possesses the optimal cutoff wavelength has the best energetic and exergetic efficiencies, which are significantly improved by 25.2% and 28.1% compared with the conventional HCEs at the solar irradiance of 800 W/m2 and inlet temperature of 580 °C. Moreover, the proposed novel HCEs have a much superior performance at lower solar irradiance. The performance-enhanced PTC system will play a significantly positive role in the performance improvement of the heating and cooling of buildings in the future.

scholarly journals Market Timing and Selectivity: An Empirical Investigation of European Mutual Fund Performance

2018 ◽  
Vol 11 (2) ◽  
pp. 1 ◽  
Author(s):  
Luís Oliveira ◽  
Tomás Salen ◽  
José Dias Curto ◽  
Nuno Ferreira
Keyword(s):  
Mutual Fund ◽  
Market Timing ◽  
Management Strategies ◽  
Fund Performance ◽  
Active Management ◽  
Superior Performance ◽  
Fund Managers ◽  
Equity Mutual Funds ◽  
Overall Performance ◽  
European Equity

Using the models proposed by (Treynor & Mazuy, 1966; Henriksson & Merton, 1981), the present study examines the selection and timing abilities of mutual fund managers to denote the practice of these strategies as a means to achieve superior performance. For the 163 European equity mutual funds that followed active management strategies between January 2000 and December 2016, there was no evidence that fund managers used market timing abilities to anticipate the market movements. However, the selectivity component of returns presents slightly positive results, despite the poor overall performance.

Driving Superior Performance in Brazilian Pre-Salt - The Challenges, Solutions and Achievements of Shell and Providers in Exploratory Pre-Salt Wells in Brazil

2021 ◽  
Author(s):  
Enrique Barrios ◽  
Rafael Santos ◽  
Robin Hartmann ◽  
Vinícius Pessanha ◽  
Romulo Adrien Neves ◽  
...  
Keyword(s):  
Performance Improvement ◽  
Continuous Improvement ◽  
Safety Culture ◽  
Service Providers ◽  
Superior Performance ◽  
Phase Duration ◽  
Drilling Performance ◽  
Collaborative Environment ◽  
World Class ◽  
Drilling Time

Abstract The Brazilian Pre-Salt has gained importance as an essential world-class province given its prolific production and thanks to its many challenges, it has incentivized the market to look for better ways to faces these technical challenges safely. This article aims to describe the main challenges faced by Shell and Constellation as well as the approach adopted to improve the operations’ safety and reduce drilling time, significantly reducing the drilling costs in an exploratory campaign in the Brazilian Pre-Salt. The campaign was based on the buildup of a partnership between the drilling contractor, operator and the main services provider, Halliburton, creating a transparent and collaborative environment, which improved all parties’ ownership and accountability. The application of many processes and techniques such as Step Seven, Stop Work Authority and Design of Work improved safety and efficiency. A precise equipment selection, detailed planning and careful execution with disciplined application of a learning mindset were also paramount to drilling performance. Four pre-salt wells were drilled in the campaign at Sul de Gato de Mato (2 wells), Alto de Cabo Frio and Saturno prospects with all of them qualifying in terms of drilling time as best in class (BIC), i.e., within the top 5% percentile. In 2019, the GdM3 well was the fastest delivery of a pre-salt well out of the 250+ wells in the region. The well GdM4 drilled in 2020 as part of the same campaign broke the previous record by seven days, being the fastest pre-salt well ever drilled with its 18 dry hole days mark. The main reason associated with the campaign´s success was the utilization of the DID-PDCA methodology, which promoted the integration of all the workforce in a cycle towards continuous improvement by: (i) carefully selecting the equipment and experienced service providers, (ii) generating detailed plans of the drilling activity and engaging all those involved in the delivery, (iii) establishing and applying a HSE strategy for safety culture enhanced and (iv) constantly monitoring of performance and discussing the next steps. Along this article a summary of well layout, the drilling phase duration, some of the key performance improvement initiatives as well as how they were generated will be shared.

Organisational Success

2015 ◽  
pp. 120-137
Author(s):  
Hee Song Ng ◽  
Daisy Mui Hung Kee
Keyword(s):  
Performance Indicators ◽  
Superior Performance ◽  
Significant Shift ◽  
Full Potential ◽  
Sustainable Competitive Advantage ◽  
Resource Based View ◽  
The Face ◽  
Performance Drivers ◽  
Overall Performance ◽  
Resources And Capabilities

Organisational success has become the focus of a growing body of research in the field. In this chapter, the authors argue that although Key Performance Indicators (KPIs) are useful for tracking tangible performance drivers, KPIs cannot adequately measure intangible performance drivers. They suggest that Key Intangible Performance Indicators (KIPs) are often the essential characteristic that drives the success of organisations. Top management should incorporate both KPIs and KIPs into success strategy in order to generate a complete picture of the overall performance of organisations. Evidently, there is a significant shift of emphasis from measuring tangible to intangible performance measures. Drawing from the Resource-Based View (RBV), superior performance is attributed to superior resources, and this helps explain why organisations should unlock the full potential of tangible and intangible resources and capabilities in attaining sustainable competitive advantage. In the face of globalisation, organisations need to transform themselves to be highly competitive in order to stay ahead of competition and at the forefront of their industries. The development and application of KIPs will be a strategic move to provide further insights and an impetus for continual improvement. The authors fill a gap in the resource-based literature by identifying four critical KIPs that influence the success of organisations, and they are leadership, innovation, reputation, and employee satisfaction.

Three-Dimensional Blade Shape Optimization for a Transonic Axial Flow Compressor Through Incorporating Surrogate Model and Sequential Sampling

2018 ◽  
Author(s):  
Xuesong Wang ◽  
Jinju Sun ◽  
Peng Song ◽  
Youwei He ◽  
Da Xu
Keyword(s):  
Surrogate Model ◽  
Pareto Front ◽  
Sequential Sampling ◽  
Axial Flow ◽  
Aerodynamic Performance ◽  
Axial Flow Compressor ◽  
Overall Performance ◽  
Flow Compressor ◽  
High Level ◽  
Performance Gains

High level aerodynamic performance has been always expected for the axial flow compressors, and it is the consistent goal for axial flow compressor research. To achieve such a goal, the incorporation of CFD with optimization algorithm and surrogate model in blade geometry optimization has become a common practice and been used extensively. But the conventional surrogate model based on merely initial sampling often deviates from the real optimization problem during optimization process and then brings the optimizer to search locally, leading to the compromised optimal results. There are yet much to do to improve such optimization design method. An optimization method of surrogate model being updated by sequential sampling strategy is developed to achieve global optimal design geometry and permit high-level of aerodynamic performance for axial flow compressor. Preliminary Kriging surrogate model is constructed with a small number of selected DOE samplings, where the multiple optimization objective functions are obtained based on CFD simulations. The optimization is performed on the surrogate model with NSGA-II optimization algorithm and Pareto fronts successively obtained. To improve the surrogate model, the MSE (Mean Squared Error) criteria is used to select the refinement point from the newest Pareto front, and it is used to update and improve the surrogate model gradually during the optimization. Such adaptive feature of the surrogate model has enabled the optimizer to search globally. The method is used to optimize transonic Rotor 37 at design flow rate, where the blade shape is varied simultaneously in terms of sweep and lean, and the geometry is optimized. In the converged Pareto front, abundant candidate designs with significant performance gains are produced. Three points over the Pareto front are selected and analyzed to take an insight into the optimization effectiveness. Overall performance curves of optimized geometries are predicted over the entire flow range and they are significantly improved compared with the original ones. Significant overall performance gains arising from the blade optimization are supported by the improved flow behavior. The overall pressure ratio or efficiency gains of the optimized blades are attributed to the significant improvement in the radial distribution of aerodynamic parameters. Further research shows that the shock structure is changed and separation zone is reduced with the optimized blades, which are the major reasons for the improvement of the aerodynamic performance of optimized blades.

scholarly journals Lean management implementation difficulties, studies and recommendations

2020 ◽  
Vol 9 (2) ◽  
pp. 527
Author(s):  
Mohammed Jouhri ◽  
Aziz Soulhi
Keyword(s):  
Continuous Improvement ◽  
Management Strategy ◽  
Apparel Industry ◽  
Lean Management ◽  
Technical Approach ◽  
Fast Fashion ◽  
Societal Values ◽  
Overall Performance ◽  
State Of Art ◽  
Made In

Speeding up FAST FASHION development cycles for the apparel industry, always bringing more values to the customer, seeking perfor-mance through continuous improvement. This paper presents a deployment approach to Lean Management, helping to make it more con-crete, efficient, less theoretical. The realization of the approach was based on case studies, state of art and references made in Moroccan companies in the textile and clothing sector. This analysis sheds light on the importance of aligning the lean management strategy with the company's strategy and values, hence the use of the socio-technical approach. The objective of this study is to realize a brief application of Lean Management, able to transform it from a theoretical organization to a practical one. This Lean Deployment Study is considered unique in that it addresses the need to work on psychology, culture, societal values of each company, to prepare for and align it with Lean manage-ment strategy, before attacking its practices. This article is a first development of strategies and methodologies proposed for improvements that seek to focus on the overall performance of the company. 

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