IFAC Proceedings Volumes最新文献

{"title":"Control of a Vibrating Axisymmetric Membrane using Piezoelectric Transducers","authors":"Sami Tliba","doi":"10.3182/20110828-6-IT-1002.03518","DOIUrl":"https://doi.org/10.3182/20110828-6-IT-1002.03518","url":null,"abstract":"Abstract In this paper, the problem of the active vibration control of a thin and flexible disc is addressed. The mechanical structure tackled here is equipped with two piezoelectric circular patches: one of them works as a sensor and the other is used as an actuator. Both are fixed on the disc, one on each side, and centered according to its axis of symmetry. The purpose of this work is to design a controller allowing the active damping of the most vibrating modes in a specified bandwidth. Robustness issues against neglected dynamics are discussed. After describing the problem, we first discuss on the model properties, derived from a finite element analysis, particularly about the structure's symmetry consequences. Then, we propose a control method leading to the reduction of several modes of vibration. Numerical simulations are proposed to analyze the modelling and the vibration control efficiency.","PeriodicalId":13260,"journal":{"name":"IFAC Proceedings Volumes","volume":"21 1","pages":"7713-7718"},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87061531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An expert system for freshwater fish-farming industry","authors":"K. Petrinec, Z. Petrinec, Z. Kovačić","doi":"10.3182/20020721-6-ES-1901.01610","DOIUrl":"https://doi.org/10.3182/20020721-6-ES-1901.01610","url":null,"abstract":"Abstract This paper deals with a technical description of an expert system for the freshwater fish-farming industry. The expert system is connected with on-site measurement equipment and by means of expert control rules supervises and controls the fish production process. Additional features such as server-clients communication via the Internet and an ability to extend a rule-base with new expert knowledge makes development of expert systems for any number of fish farms possible. Access via Internet enables better supervision, planning and better utilization of production resources, which results in turn with increased quality of fish, increased fish growth and bigger profits.","PeriodicalId":13260,"journal":{"name":"IFAC Proceedings Volumes","volume":"19 1","pages":"339-344"},"PeriodicalIF":0.0,"publicationDate":"2019-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88023222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Platelet count control in immune thrombocytopenic purpura patient: optimum romiplostim dose profile","authors":"Chia-Hung Tsai, J. Bussel, Allison Imahiyerobo, S. Sandler, B. Ogunnaike","doi":"10.3182/20140824-6-ZA-1003.00474","DOIUrl":"https://doi.org/10.3182/20140824-6-ZA-1003.00474","url":null,"abstract":"Abstract Patients with immune thrombocytopenic purpura (ITP), a disease characterized by abnormally low platelet count, are susceptible to excessive bleeding as a direct consequence. While the problem of low platelet count can be addressed fundamentally either by slowing down the rate of platelet destruction or by increasing platelet production, or both, one of the more effective means of treating ITP patients is to increase platelet production with romiplostim. However, current romiplostim treatment strategies tend to produce undesirable responses where platelet counts oscillate between dangerously low values and extremely high peaks, as a direct consequence of the complex nonlinear dynamics associated with platelet count regulation. The objective of this study is to determine the optimum dose profile of romiplostim for a specific ITP patient required to maintain a platelet count of 70×109/L. Using clinical data of the specific patient's platelet count obtained in response to a series of subcutaneously applied doses of romiplostim, a standard pharmacokinetics/pharmacodynamics (PKPD) model was developed, validated, and analyzed to obtain insight into the patient's physiological characteristics. The model was subsequently used to investigate the performance of three control strategies: “fixed dose” open-loop control, “variable dose” discrete PI feedback control, and “variable dose” model-based open-loop optimal control. The control strategies were implemented for weekly and bi-weekly treatment regimens. With both treatment frequencies, the fixed dose open-loop control strategy resulted in unacceptable sustained oscillating platelet count. PI feedback control and model-based optimal open-loop control led to stable platelet count profiles after approximately 50 days but only for weekly injections. In summary, a stable platelet count is more likely to be achieved consistently in the specific patient with weekly treatments. Bi-weekly treatments are less effective because, as we show, fundamental pharmaceutical characteristics of romiplostim make oscillations in platelet count unavoidable at this treatment frequency. The results show that model-based decisions determined using patient-specific mathematical models are potentially useful for designing better treatment regimens for ITP patients.","PeriodicalId":13260,"journal":{"name":"IFAC Proceedings Volumes","volume":"1 1","pages":"11800-11805"},"PeriodicalIF":0.0,"publicationDate":"2016-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90899646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Hybrid Model of the Akamai Adaptive Streaming Control System","authors":"L. D. Cicco, G. Cofano, S. Mascolo","doi":"10.3182/20140824-6-ZA-1003.01021","DOIUrl":"https://doi.org/10.3182/20140824-6-ZA-1003.01021","url":null,"abstract":"Abstract Video streaming is becoming the application generating the largest fraction of the Internet traffic. Adaptive video streaming adds to classic video streaming the feature of dynamically adapting the video bitrate to track the time-varying network available bandwidth, avoid playback interruptions and ensure the delivery of the best video quality. In this paper we focus on the adaptive video streaming control system employed by Akamai, a major CDN operator whose video delivery system is used by several video streaming platforms, including Livestream. Differently from the typical client-side control, Akamai employs an interesting and unique hybrid client/server control architecture. Our purpose is to derive and validate a closed loop mathematical model of the control system, which turns out to be a hybrid automaton. The model is then analyzed to derive key properties which can be used to properly tune the controller parameters.","PeriodicalId":13260,"journal":{"name":"IFAC Proceedings Volumes","volume":"26 1","pages":"3321-3326"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81573650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Control of an Industrial Scale Bioreactor using a PAT Analyser","authors":"S. Goldrick, E. Mercer, G. Montague, D. Lovett, B. Lennox","doi":"10.3182/20140824-6-ZA-1003.02589","DOIUrl":"https://doi.org/10.3182/20140824-6-ZA-1003.02589","url":null,"abstract":"Abstract This work investigates the application of a “Process Analytical Technology” (PAT) analyser to control the substrate concentration over traditional sequential batch control for an industrial scale fed-batch penicillin fermentation. A simulation that utilises the historical data from four batches, where a sequential batch control strategy was implemented, was used as the benchmark reference for this comparison. The simulation accurately predicts the main outputs variables of biomass and penicillin, given the inputs from the historical data set. The simulation includes a PAT analyser, used to build a calibration model with the available off-line substrate concentration from one of the batches. The prediction from this calibration model was used as the controlled variable within a proportional integral (PI) controller to manipulate the substrate feed rate for the three remaining batches. Performance of each control strategy was analysed by comparing the final penicillin yield of each batch. An increase of 35, 20 and 9% was observed for the three batches controlled using the PI controller compared with the sequential batch control strategy.","PeriodicalId":13260,"journal":{"name":"IFAC Proceedings Volumes","volume":"94 1","pages":"6222-6227"},"PeriodicalIF":0.0,"publicationDate":"2016-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91378991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"System Identification and Distributed Control for Multi-rate Sampled Systems","authors":"Q. Shao, A. Çinar","doi":"10.3182/20140824-6-ZA-1003.01715","DOIUrl":"https://doi.org/10.3182/20140824-6-ZA-1003.01715","url":null,"abstract":"Abstract System outputs with different sampling times may cause difficulties in subspace identification to obtain an accurate model when some system variables are sampled at faster rate. This identification problem is solved by dividing the multi-rate sampled system into different subsystems, and multi-rate distributed control is proposed to control such system by using the identified model.","PeriodicalId":13260,"journal":{"name":"IFAC Proceedings Volumes","volume":"6 1","pages":"11653-11658"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88321253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Knowledge Base Representation for Humanoid Robot Skills","authors":"Daniel Hernández García, C. Monje, C. Balaguer","doi":"10.3182/20140824-6-ZA-1003.02229","DOIUrl":"https://doi.org/10.3182/20140824-6-ZA-1003.02229","url":null,"abstract":"Abstract The ultimate goal for humanoid robotics research is to develop humanoid robotic systems capable and flexible enough to handle the challenge of working alongside human in complex natural environments performing everyday tasks. To reach this goal it is key to develop appropriate structures in which to organize the acquire knowledge in a manner that allows the system to retrieve it in order to use it to fulfil its missions. In this work a knowledge base representation of the robot skills knowledge organized in terms of the relationships between objects, actions and event frames is proposed.","PeriodicalId":13260,"journal":{"name":"IFAC Proceedings Volumes","volume":"12 1","pages":"3042-3047"},"PeriodicalIF":0.0,"publicationDate":"2014-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73582166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Extension to the First Order Model of Pulmonary Mechanics to Capture a Pressure dependent Elastance in the Human Lung","authors":"A. Knörzer, P. Docherty, Y. Chiew, J. Chase, K. Möller","doi":"10.3182/20140824-6-ZA-1003.01834","DOIUrl":"https://doi.org/10.3182/20140824-6-ZA-1003.01834","url":null,"abstract":"\u0000 Mechanical ventilation (MV) is a lifesaving therapy for patients with the acute respiratory distress syndrome. However, selecting the optimal MV settings is a difficult process as setting a high positive end-expiratory pressure (PEEP) value will improve oxygenation, but can produce ventilator induced lung injuries (VILI). To find a suitable value is patient specific and depends on different things like the underlying illness and the current state. In this study, a respiratory model that defined constant bronchial resistance and pressure-dependent variable elastance was fitted to pressure volume (PV) responses for 12 datasets of 10 acute respiratory distress syndrome (ARDS) patients which underwent a recruitment maneuver (RM) to open previous collapsed alveoli. We believe that the range of minimal elastance represents that range in which oxygenation can be improved by recruitment with reducing the risk of VILI.\u0000 The first order model with a variable elastance (Edrs\u0000 ) described by Chiew et al. (2011) was modified with a factor α to express added end-expiratory volume due to an increased PEEP. Model parameters were identified using a nonlinear least square method that optimized Edrs\u0000 agreement across PEEP-levels.\u0000 The model yielded an increase in overlapping quality of pressure dependent Edrs\u0000 -curves. A best pressure range for PEEP could be identified in 9 of 12 datasets. The model could potentially provide a simple method of decision support at the bedside for clinicians and could prospectively an automated extend in mechanical ventilation devices.\u0000","PeriodicalId":13260,"journal":{"name":"IFAC Proceedings Volumes","volume":"18 1","pages":"1176 - 1181"},"PeriodicalIF":0.0,"publicationDate":"2014-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89908430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adaptive Observers for Nonlinearly Parameterized Systems Subjected to Parametric Constraints","authors":"I. Tyukin, P. A. Rogachev, H. Nijmeijer","doi":"10.3182/20140824-6-ZA-1003.00807","DOIUrl":"https://doi.org/10.3182/20140824-6-ZA-1003.00807","url":null,"abstract":"We consider the problem of adaptive observer design in the settings when the system is allowed to be nonlinear in the parameters, and furthermore they are to satisfy additional feasibility constraints. A solution to the problem is proposed that is based on the idea of employing observers comprising of an exponentially converging part coupled with exploratory dynamics (cf. Tyukin et al. (2013)). The procedure is illustrated with an example.","PeriodicalId":13260,"journal":{"name":"IFAC Proceedings Volumes","volume":"26 1","pages":"10869-10874"},"PeriodicalIF":0.0,"publicationDate":"2014-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80807970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cooperative Allocation and Guidance for Air Defence Application","authors":"S. L. Ménec, K. Markham, A. Tsourdos, Hyo-Sang Shin, H. Piet-Lahanier","doi":"10.3182/20110828-6-IT-1002.02520","DOIUrl":"https://doi.org/10.3182/20110828-6-IT-1002.02520","url":null,"abstract":"Abstract This project proposes a centralised algorithm to design cooperative allocation strategies and guidance laws for air defence applications. Scenarios in naval and ground context have been defined for performance analysis by comparison to a benchmark target allocation policy. The cooperative target allocation algorithm is based on the following features: No Escape Zones (differential game NEZ) computation to characterise the defending missile capturability characteristics; In Flight (re) Allocation (IFA algorithm, late committal guidance) capability to deal with target priority management and pop up threats; capability to generate and counter alternative target assumptions based on concurrent beliefs of future target behaviours, i.e. Salvo Enhanced No Escape Zone (SENEZ) algorithm. The target trajectory generation has been performed using goal oriented trajectory extrapolation techniques. The target allocation procedure is based on minimax strategy computation in matrix games.","PeriodicalId":13260,"journal":{"name":"IFAC Proceedings Volumes","volume":"16 1","pages":"3897-3902"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74009095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}