LQG control for dynamic positioning of floating caissons based on the Kalman filter

This paper presents the application of an linear quadratic gaussian (LQG) control strategy for concrete caisson deployment for marine structures. Currently these maneuvers are carried out manually with the risk that this entails. Control systems for these operations with classical regulators have begun to be implemented. They try to reduce risks, but they still need to be optimized due to the complexity of the dynamics involved during the sinking process and the contact with the sea bed. A linear approximation of the dynamic model of the caisson is obtained and an LQG control strategy is implemented based on the Kalman filter (KF). The results of the proposed LQG control strategy are compared to the ones given by a classic controller. It is noted that the proposed system is positioned with greater precision and accuracy, as shown in the different simulations and in the Monte Carlo study. Furthermore, the control efforts are less than with classical regulators. For all the reasons cited above, it is concluded that there is a clear improvement in performance with the control system proposed.The Spanish FEDER/Ministry of Science, Innovation and Universities—State Research Agency is greatly acknowledged for partially funding our research through the SAFE Project (Desarrollo de un Sistema Autónomo para el Fondeo de Estructuras para Obras Marítimas), GrantAgreement: RTC-2017-6603-4. The Regional Ministry of Universities, Equality, Culture and Sports of the Gov-ernment of Cantabria has supported this work through the ControlFond project (Control De Ve-hículos Subacuáticos No Tripulados Para Supervisión De Estructuras Para Obras Marítimas Fondeadas). The authors would like to thank FCC Construcción CO as a collaborator in the de-velopment of the SAFE Project, specially Victor Florez Casillas and Nuria Cotallo Aguado (Tech-nical Direction/Hydraulic and Maritime Works) and Alvaro de Toro Mingo (Machinery Direction). R. Guanche also acknowledges financial support from the Ramon y Cajal Program (RYC-2017-23260) of the Spanish Ministry of Science, Innovation and Universities

Dynamic positioning of floating caissons based on the UKF filter under external perturbances induced by waves

This paper presents a dynamic positioning control scheme for concrete caissons in an attempt to automate part of the manoeuvres which usually require a complex deploy of personnel and equipment for port infrastructures development. The aim of this paper is to propose a control scheme, which is able to provide a reduction in costs and an improvement in security for the dynamic positioning manoeuvres . To do so, a dual loop controller is developed and the unscented Kalman filter is applied for states and perturbances estimation. Furthermore, a control allocation algorithm is proposed based on anchoring lines and winches. Finally, some simulations are performed to verify the effectiveness of the proposed approach.The Spanish FEDER/Ministry of Science, Innovation and Universities — State Research Agency (Fig. 14) is greatly acknowledged for funding our research through SAFE Project (Desarrollo de un Sistema Autónomo para el Fondeo de Estructuras para Obras Marítimas), Grant Agreement: RTC-2017-6603-4. The authors would like to thank FCC CO as a collaborator in the development of the SAFE Project. R. Guanche also acknowledges financial support from the Ramon y Cajal Program (RYC-2017-23260) of the Spanish Ministry of Science, Innovation and Universities

Methodology for integrated socio-economic assessment of offshore platforms : towards facilitation of the implementation of the marine strategy framework directive

In this paper a Methodology for Integrated Socio-Economic Assessment (MISEA) of the viability and sustainability of different designs of Multi-Use Offshore Platforms (MUOPs) is presented. MUOPs are designed for multi-use of ocean space for energy extraction (wind power production and wave energy), aquaculture and transport maritime services. The developed methodology allows identification, valuation and assessment of: the potential range of impacts of a number of feasible designs of MUOP investments, and the likely responses of those impacted by the investment project. This methodology provides decision-makers with a valuable decision tool to assess whether a MUOP project increases the overall social welfare and hence should be undertaken, under alternative specifications regarding its design, the discount rate and the stream of net benefits, if a Cost-Benefit Analysis (CBA) is to be followed or sensitivity analysis of selected criteria in a Multi-Criteria Decision Analysis (MCDA) framework. Such a methodology is also crucial for facilitating of the implementation of the Marine Strategy Framework Directive (MSFD adopted in June 2008) that aims to achieve good environmental status of the EU's marine waters by 2020 and to protect the resource base upon which marine-related economic and social activities depend. According to the MSFD each member state must draw up a program of cost-effective measures, while prior to any new measure an impact assessment which contains a detailed cost-benefit analysis of the proposed measures is required

Phase I clinical trial in healthy adults of a nasal vaccine candidate containing recombinant hepatitis B surface and core antigens

SummaryBackgroundThe nasal vaccine candidate (NASVAC), comprising hepatitis B virus (HBV) surface (HBsAg) and core antigens (HBcAg), has been shown to be highly immunogenic in animal models.MethodsA phase I double-blinded, placebo-controlled randomized clinical trial was carried out in 19 healthy male adults with no serologic markers of immunity/infection to HBV. This study was aimed at exploring the safety and immunogenic profile of nasal co-administration of both HBV recombinant antigens. The trial was performed according to Good Clinical Practice guidelines. Participants ranged in age from 18 to 45 years and were randomly allocated to receive a mixture of 50μg HBsAg and 50μg HBcAg or 0.9% physiologic saline solution, as a placebo, via nasal spray in a five-dose schedule at 0, 7, 15, 30, and 60 days. A total volume of 0.5ml was administered in two dosages of 125μl per nostril. Adverse events were actively recorded 1h, 6h, 12h, 24h, 48h, 72h, 7 days and 30 days after each dose. Anti-HBs and anti-HBc titers were evaluated using corresponding ELISA kits at days 30 and 90.ResultsThe vaccine candidate was safe and well tolerated. Adverse reactions included sneezing (34.1%), rhinorrhea (12.2%), nasal stuffiness (9.8%), palate itching (9.8%), headache (9.8%), and general malaise (7.3%). These reactions were all self-limiting and mild in intensity. No severe or unexpected events were recorded during the trial. The vaccine elicited anti-HBc seroconversion in 100% of subjects as early as day 30 of the immunization schedule, while a seroprotective anti-HBs titer (≥10IU/l) was at a maximum at day 90 (75%). All subjects in the placebo group remained seronegative during the trial.ConclusionThe HBsAg–HBcAg vaccine candidate was safe, well tolerated and immunogenic in this phase I study in healthy adults. To our knowledge, this is the first demonstration of safety and immunogenicity for a nasal vaccine candidate comprising HBV antigens

Metodología para la optimización de la maniobra de fondeo de cajones en infraestructuras marítimas

Los autores agradecen el soporte y la financiación del proyecto DOVICAIM. Proyecto del Programa estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad 2014 (RTC-2014-3077-4

Effectiveness of a multidimensional approach for prevention of ventilator-associated pneumonia in 11 adult intensive care units from 10 cities of Turkey: Findings of the International Nosocomial Infection Control Consortium (INICC)

Purpose: To evaluate the impact of the International Nosocomial Infection Control Consortium (INICC) multidimensional approach on the reduction of ventilator-associated pneumonia (VAP) in adult patients hospitalized in 11 intensive care units (ICUs), from 10 hospitals, members of the INICC, in 10 cities of Turkey. Methods: A prospective active before-after surveillance study was conducted to determine the effect of the INICC multidimensional approach in the VAP rate. The study was divided into two phases. In phase 1, active prospective surveillance of VAP was conducted using the definitions of the Centers for Disease Control and Prevention National Health Safety Network, and the INICC methods. In phase 2, we implemented the multidimensional approach for VAP. The INICC multidimensional approach included the following measures: (1) bundle of infection control interventions, (2) education, (3) outcome surveillance, (4) process surveillance, (5) feedback of VAP rates, and (6) performance feedback of infection control practices. We compared the rates of VAP obtained in each phase. A time series analysis was performed to assess the impact of our approach. Results: In phase 1, we recorded 2,376 mechanical ventilator (MV)-days, and in phase 2, after implementing the multidimensional approach, we recorded 28,181 MV-days. The rate of VAP was 31.14 per 1,000 MV-days during phase 1, and 16.82 per 1,000 MV-days during phase 2, amounting to a 46 % VAP rate reduction (RR, 0.54; 95 % CI, 0.42-0.7; P value, 0.0001.) Conclusions: The INICC multidimensional approach was associated with a significant reduction in the VAP rate in these adult ICUs of Turkey. © 2013 Springer-Verlag Berlin Heidelberg