Tester capacity control at Qimonda Portugal

Estágio realizado na Qimonda Portugal e orientado pelo Eng.º Jorge SousaTese de mestrado integrado. Engenharia Industrial e Gestão. Faculdade de Engenharia. Universidade do Porto. 200

Learning Agent for a Heat-Pump Thermostat With a Set-Back Strategy Using Model-Free Reinforcement Learning

The conventional control paradigm for a heat pump with a less efficient auxiliary heating element is to keep its temperature set point constant during the day. This constant temperature set point ensures that the heat pump operates in its more efficient heat-pump mode and minimizes the risk of activating the less efficient auxiliary heating element. As an alternative to a constant set-point strategy, this paper proposes a learning agent for a thermostat with a set-back strategy. This set-back strategy relaxes the set-point temperature during convenient moments, e.g. when the occupants are not at home. Finding an optimal set-back strategy requires solving a sequential decision-making process under uncertainty, which presents two challenges. A first challenge is that for most residential buildings a description of the thermal characteristics of the building is unavailable and challenging to obtain. A second challenge is that the relevant information on the state, i.e. the building envelope, cannot be measured by the learning agent. In order to overcome these two challenges, our paper proposes an auto-encoder coupled with a batch reinforcement learning technique. The proposed approach is validated for two building types with different thermal characteristics for heating in the winter and cooling in the summer. The simulation results indicate that the proposed learning agent can reduce the energy consumption by 4-9% during 100 winter days and by 9-11% during 80 summer days compared to the conventional constant set-point strategyComment: Submitted to Energies - MDPI.co

LEAN SIX SIGMA APPROACH FOR LABOR PRODUCTIVITY IMPROVEMENT AT FINAL TEST SEMICONDUCTOR MANUFACTURING

Labor productivity improvement is all about getting more units out with the same or lesser amount of labor. Due to the economic downturn, the semiconductor company under study wanted to determine the ideal number of operators to be employed especially at the critical operations in order to minimize the labor cost and improve labor productivity. Thus, the main focus of the study is to perform analysis at the bottleneck area in order to determine the labor utilization and also toidentify the ideal man to machine ratio at the semi-automatic final test operation. The lean work study analysis using Process Mapping and Maynard Operational Sequence Technique (MOST) also enabled the authors to unveil the various types of wastes occurring at the final test area in order to propose lean improvement activities. Six Sigma Define, Measure, Analyze, Improve and Control (DMAIC) approach was employed during the implementation of the study.The results of the final test area Lean Six Sigma study showed significant improvements could be made on the labor utilization and man to machine ratio. With the knowledge of how to improve the labor productivity, the semiconductor company will be on the right track towards achieving a leaner and more cost effective operation

Impact Analysis of Implementation of Automation Technology on Refrigerator Out Door Forming Process in Electronics Company Tangerang

This research is conducted at an electronics company in Tangerang which produces a refrigerator with an average production capacity of 5,500 units per day. To improve productivity in the manufacturing process at the company has done several automation processes in several workstations that allow automation processes. Takt time reduce from 12 seconds to 8.5 seconds and the number of operators 80% decreased from 10 operators to only 2 operators. It also has the effect of reducing the possible risk of accidents for operators. Automation processes using robots have advantages in terms of process stability and ease in the adjustment of motion, making it particularly appropriate in automation processes in the manufacturing process industry. That is based on analysis conducted by using SWOT analysis method

Analysis and Control of Multimode Combustion Switching Sequence.

Highly dilute, low temperature combustion technologies, such as homogeneous charge compression ignition (HCCI), show significant improvements in internal combustion engine fuel efficiency and engine-out NOx emissions. These improvements, however, occur at limited operating range and conventional spark ignition (SI) combustion is still required to fulfill the driver's high torque demands. In consequence, such multimode engines involve discrete switches between the two distinct combustion modes. Such switches unfortunately require a finite amount of time, during which they exhibit penalties in efficiency. Along with its challenges, the design of such a novel system offers new degrees of freedom in terms of engine and aftertreatment specifications. Prior assessments of this technology were based on optimistic assumptions and neglected switching dynamics. Furthermore, emissions and driveability were not fully addressed. To this end, a comprehensive simulation framework, which accounts for above-mentioned penalties and incorporates interactions between multimode engine, driveline, and three-way catalyst (TWC), has been developed. Experimental data was used to parameterize a novel mode switch model, formulated as finite-state machine. This model was combined with supervisory controller designs, which made the switching decision. The associated drive cycle results were analyzed and it was seen that mode switches have significant influence on overall fuel economy, and the issue of drivability needs to be addressed within the supervisory strategy. After expanding the analysis to address emissions assuming a TWC, it was shown that, in practice, HCCI operation requires the depletion of the TWC's oxygen storage capacity (OSC). For large OSCs the resulting lean-rich cycling nullifies HCCI's original efficiency benefits. In addition, future emissions standards are still unlikely to be fulfilled, deeming a system consisting of such a multimode engine and TWC with generous OSC unfavorable. In view of these difficulties, the modeling framework was extended to a mild hybrid electric vehicle (HEV) allowing a prolonged operation in HCCI mode with associated fuel economy benefits during city driving. Further analysis on how to reduce NOx while maintaining fuel economy resulted in a counterintuitive suggestion. It was deemed beneficial to constrain the HCCI operation to a small region, exhibiting lowest NOx, while reducing instead of increasing the OSC.PhDMechanical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/116660/1/snuesch_1.pd

An approach to a maintenance plan for a turbine of hydroelectric power plant. Optimisation based in RCM and FMECA analysis

[EN] The generation of electric energy is a continuous process of great strategic importance in the development of countries. The evolution in the last decades of different environmental control protocols at a global level has influenced the rise of renewable energies with low impact on the environment. These reasons make it important that this process has an effective maintenance management system that guarantees adequate reliability, availability and useful life of its assets. This article describes the implementation of the optimization of the traditional preventive maintenance that is carried out in regular temporary intervals with unavailability of the hydroelectric group, to be able to take advantage of the data base of operation of the group (failure modes, criticality, application of maintenance strategies to condition and maintenance 4.0, etc…).The author is grateful for the transmission of the best practices to the staff of the UPH Ebro Pirineos of the company Enel Green Power Hydro Iberia. Especially to Maria Soledad Ordoñez (Director UPH) and Luis Leon (Head UT Lleida) for the implementation of improvement working groups within the territorial unit.Martinez-Monseco, FJ. (2021). An approach to a maintenance plan for a turbine of hydroelectric power plant. Optimisation based in RCM and FMECA analysis. Journal of Applied Research in Technology & Engineering. 2(1):39-50. https://doi.org/10.4995/jarte.2021.14761OJS395021Bloom, N. (2006). Reliability Centered Maintenance (RCM): Implementation made Simple. McGraw-Hill New York.Calixto, E. (2016). Gas and Oil Reliability Engineering: Modelling and Analysis. Gulf Professional Publishing. https://doi.org/10.1016/B978-0-12-805427-7.00007-5Egusquiza, E., Nascimento, P., Valero, C., Jou, E. (1994). Diagnóstico de daños en grupos hidroeléctricos mediante análisis de vibraciones. Revista Ingeniería del agua, 1(3), 69. https://doi.org/10.4995/ia.1994.2645Garcia Illescas, R., Perez Rodriguez, N. (2007). Análisis de malfuncionamiento y de falla de una turbina hidráulica de 15 MW. X Congreso y exposición latinoamericana de maquinaria. 6-9 noviembre. Veracruz, México. 2007.Gulliver, J.S., Arndt, R.E. (1991). Hydropower engineering handbook. McGraw-Hill, Inc.Martínez Monseco, F.J. (2013). "Diseño de un plan de mantenimiento para un equipo de alta fiabilidad," Técnica Industrial, 301, 40-53.Martínez Monseco, F.J. (2016). Datos de la investigación y el estudio de sistemas central hidroeléctrica en desarrollo tesis doctoral en curso "Análisis y planificación del mantenimiento y explotación de una central hidroeléctrica basado en técnicas cualitativas de confiabilidad. RCM y AMFEC." Escuela de Doctorado-ETSII UNED Ingenieros Industriales,Martínez Monseco, F.J. (2020). Analysis of maintenance optimization in a hydroelectric power plant. Journal of Applied Research in Technology & Engineering, 1(1), 23-29. https://doi.org/10.4995/jarte.2020.13738Moubray, J. (1997). Reliability-Centered Maintenance. Industrial Press Inc.Sifonte, J.R., Reyes-Picknell, J.V. (2017). Reliability Centered Maintenance-Reengineered: Practical Optimization of the RCM Process with RCM-R®. Productivity Press. https://doi.org/10.1201/9781315207179Vargas Castillo, E., Caicedo Delgado, N.G., Ortega Henio, J.D.(2019). Método de análisis de fallos aplicado a centrales hidroelectricas. I+D Revista de investigación, 13(1), 57-72. https://doi.org/10.33304/revinv.v13n1-201900

Proposal for the development of burn-in inline

Advanced manufacturing promises to significantly impact the economy in various branches and industrial segments, such as metallurgy and agribusiness. Therefore, the aim is to develop a new product implemented at the company Transire, an automated system for storage in a controlled temperature environment, testing and test monitoring in real-time of its final products. Thus, this article can be considered exploratory, applied, and qualitative under the aspects of bibliographical research and case studies. Data collection was through meetings with company professionals, technical visits, and research on the importance of the topic. The results showed that the main stages of development of the Burn-In Inline were validated and that studies of production capacity associated with these developments can generate factory modernization and greater competitiveness among companies in the fiel

Modeling, Validation and Verification of Concurrent Behavior in Canal System Using LTSA and UPPAAL

A complex system is composed of subsystems. Common sense dictates complex systems in the physical world are reactive and concurrent in nature. The procedure to model a concurrent system and the procedure to validate its performance are complex because of the presence of the interactions between and among the subsystems, calling for an integrated approach from the viewpoint of systems engineering. In this thesis, a canal system is the object of study. The main objectives are to achieve a deadlock free and safe architectural model of a canal system, as measured by transportation criteria. Specifically, the Panama Canal is used as a case study where a procedure has been developed to model this waterway. This thesis models the scenario-based specifications, system behavioral model, animated verification and validation of the Panama Canal with LTSA and with the help of UPPAAL brings time constraints into the canal behavioral model

Uph Improvement On Production Line A Case Study

In manufacturing industries, Lean Manufacturing is a broadly accepted philosophy. Initially, the Lean Manufacturing concept was started from the Toyota Production System (TPS). Nowadays, most of the manufacturers tend to implement lean manufacturing to improve their production and performance in order to maintain a competitive advantage in the business environment. The purpose of this paper is to study the unit per hour (UPH) improvement on the production line. This thesis focused on the improvement of UPH and the reduction of cycle time in a production line. The production line is a manual assembly line. The initial condition of the production of the product such as cycle time and takt time was collected from time study and the data was analyzed. The cycle time for a substation in each line which is Left, Remote and Right were given attention to see which station has the highest cycle time. The lean manufacturing approach helps to identify the problem in the production line and help detect the improvement opportunities in the production line. The outcome from the implementation of improvement shows the reduction of cycle time for the bottleneck station at least 37% and the output of the production able to achieve 105 units per hour

High fidelity simulation models for equipment performance prediction in semiconductor industry

Semiconductor manufacturing is a high-technology industry which is capital intensive and operationally complex with its process technology refreshed every two years. Precision in capacity planning is critical to ensure the right amount of capital equipment is purchased to match the demand while meeting aggressive cost and operational targets. The key input parameter for capacity calculations is the equipment output rate. As equipment get more complex, its output rate become difficult to predict using spreadsheets, thus the need for detailed dynamic equipment simulation models. However, literature on how to build detailed equipment simulation models for real-world is scarce. Practitioners do not share their experience openly due to proprietary reasons. This dissertation investigates the complexity of semiconductor manufacturing which makes its capacity planning difficult. The techniques to build, verify and validate high fidelity equipment simulation models were developed. The models are then used to augment capacity planning and productivity improvement decision making. Case studies are conducted using the models to improve capacity forecast planning accuracy for capital purchase decisions which resulted in million dollars capital avoidance, test equipment productivity improvement ideas and decide which ones have benefits to pursue, and determine the effect of different operator manning ratios for manufacturing execution decisions. The results show that raw model accuracy can be up to 99% using the methods described here. For manufacturing execution, model accuracy can be up to 95% due to variability in human performance, but good enough to provide insights on manning ratio strategies. The case studies demonstrate how the results directly contribute to company performance in terms of capital efficiency, capital expenditure avoidance, and waste reduction. It enables optimal equipment configuration decisions to be made upfront during technology development. It also earns credibility and senior management confidence in using such simulation models for decision making