Analysis of Onshore Synthetic Inertia and Primary Control Reserve Contributions of Alternating Current-Side Meshed Offshore Grids with Voltage-Source Converter and Diode Rectifier Unit High-Voltage Direct Current Connections

The increasing use of renewable energy sources in place of conventional generation units is leading to a reduction in onshore inertia and to the development of offshore wind park grids connected by multiple high-voltage direct current (HVDC) connections to the onshore alternating current (AC) grid. For AC-side meshed offshore grids with voltage-source converter (VSC) and diode rectifier unit (DRU) HVDC connections towards onshore grids, this study focuses on the energetic feasibility of synthetic inertia (SI) and primary control reserve (PCR) contributions triggered locally at the onshore converters of both connection types. To this end, the obstacles preventing contributions for VSC HVDC connections and the mechanisms allowing contributions for DRU HVDC connections are identified first. Based on these findings, the article proposes an enhancement of the offshore HVDC converter controls that is continuously active and allows locally triggered onshore contributions at all onshore HVDC converters of both connection types without using communication and requiring only minimal system knowledge. Additional simulations confirm that, although the enhancement is continuously active, the operational performance of the offshore HVDC converter controls for normal offshore grid operation and its robustness against offshore AC-side faults are not affected

Fabrication of nanocrystalline high-entropy oxide CoNiFeCrMnOₓ thin film electrodes by dip-coating for oxygen evolution electrocatalysis

The variation of calcination conditions allows for adjusting the oxidation states and coordination sites of near-surface elements in sol–gel-derived high-entropy oxides. Optimized synthesis conditions resulted in fabrication of nanocrystalline CoNiFeCrMnOₓ thin films with 1–2 nm pores, showing low OER overpotentials of 258 mV vs. RHE at 10 mA cm⁻²

Modelling the Interfacial Flow of Two Immiscible Liquids in Mixing Processes

This paper presents an interface tracking method for modelling the flow of immiscible metallic liquids in mixing processes. The methodology can provide an insight into mixing processes for studying the fundamental morphology development mechanisms for immiscible interfaces. The volume-of-fluid (VOF) method is adopted in the present study, following a review of various modelling approaches for immiscible fluid systems. The VOF method employed here utilises the piecewise linear for interface construction scheme as well as the continuum surface force algorithm for surface force modelling. A model coupling numerical and experimental data is established. The main flow features in the mixing process are investigated. It is observed that the mixing of immiscible metallic liquids is strongly influenced by the viscosity of the system, shear forces and turbulence. The numerical results show good qualitative agreement with experimental results, and are useful for optimisating the design of mixing casting processes

The development of spatial correlations during Ostwald ripening: a test of theory

AbstractÐThe coarsening of solid-Sn particles in a Pb±Sn liquid was studied under microgravity conditions. Spatial correlation functions were measured on plane sections in a low-volume fraction system undergoing Ostwald ripening. The correlation functions changed with time in a way that indicated that the microstructure initially consisted of clusters of particles and evolved into one which was more dispersed. The model by Akaiwa and Voorhees (AV) was used to study the eect of spatial correlations on the ripening process. We found that the initially highly correlated structure had no observable eect on the evolution of particle size distributions, but did have an eect on the coarsening rate of the system. Speci®cally, we determined that a structure consisting of clusters of particles coarsened faster than a system with a random, spatial arrangement of non-overlapping particles. We also found that the approach of the microstructure towards the steady-state regime could be monitored more sensitively using spatial correlations rather than using particle size distributions. The spatial correlations and the particle size distributions measured from the experiment agreed well with those calculated from the AV simulations using the initial experimental correlations and size distribution.

Columnar and Equiaxed Solidification of Al-7 wt.% Si Alloys in Reduced Gravity in the Framework of the CETSOL Project

International audienceDuring casting, often a dendritic microstructure is formed, resulting in a columnar or an equiaxed grain structure, or leading to a transition from columnar to equiaxed growth (CET). The detailed knowledge of the critical parameters for the CET is important because the microstructure affects materials properties. To provide unique data for testing of fundamental theories of grain and microstructure formation, solidification experiments in microgravity environment were performed within the European Space Agency Microgravity Application Promotion (ESA MAP) project Columnar-to-Equiaxed Transition in SOLidification Processing (CETSOL). Reduced gravity allows for purely diffusive solidification conditions, i.e., suppressing melt flow and sedimentation and floatation effects. On-board the International Space Station, Al-7 wt.% Si alloys with and without grain refiners were solidified in different temperature gradients and with different cooling conditions. Detailed analysis of the microstructure and the grain structure showed purely columnar growth for nonrefined alloys. The CET was detected only for refined alloys, either as a sharp CET in the case of a sudden increase in the solidification velocity or as a progressive CET in the case of a continuous decrease of the temperature gradient. The present experimental data were used for numerical modeling of the CET with three different approaches: (1) a front tracking model using an equiaxed growth model, (2) a three-dimensional (3D) cellular automaton–finite element model, and (3) a 3D dendrite needle network method. Each model allows for predicting the columnar dendrite tip undercooling and the growth rate with respect to time. Furthermore, the positions of CET and the spatial extent of the CET, being sharp or progressive, are in reasonably good quantitative agreement with experimental measurements

Estimation of cooling rates during close-coupled gas atomization using secondary dendrite arm spacing measurement

Al-4 wt pct Cu alloy has been gas atomized using a commercial close-coupled gas-atomization system. The resulting metal powders have been sieved into six size fractions, and the SDAS has been determined using electron microscopy. Cooling rates for the powders have been estimated using a range of published conversion factors for Al-Cu alloy, with reasonable agreement being found between sources. We find that cooling rates are very low relative to those often quoted for gas-atomized powders, of the order of 10 K s for sub-38 μm powders. We believe that a number of numerical studies of gas atomization have overestimated the cooling rate during solidification, probably as a consequence of overestimating the differential velocity between the gas and the particles. From the cooling rates measured in the current study, we estimate that such velocities are unlikely to exceed 20 m s

Multiple Myeloma Treatment in Real-world Clinical Practice : Results of a Prospective, Multinational, Noninterventional Study

Funding Information: The authors would like to thank all patients and their families and all the EMMOS investigators for their valuable contributions to the study. The authors would like to acknowledge Robert Olie for his significant contribution to the EMMOS study. Writing support during the development of our report was provided by Laura Mulcahy and Catherine Crookes of FireKite, an Ashfield company, a part of UDG Healthcare plc, which was funded by Millennium Pharmaceuticals, Inc, and Janssen Global Services, LLC. The EMMOS study was supported by research funding from Janssen Pharmaceutical NV and Millennium Pharmaceuticals, Inc. Funding Information: The authors would like to thank all patients and their families and all the EMMOS investigators for their valuable contributions to the study. The authors would like to acknowledge Robert Olie for his significant contribution to the EMMOS study. Writing support during the development of our report was provided by Laura Mulcahy and Catherine Crookes of FireKite, an Ashfield company, a part of UDG Healthcare plc, which was funded by Millennium Pharmaceuticals, Inc, and Janssen Global Services, LLC. The EMMOS study was supported by research funding from Janssen Pharmaceutical NV and Millennium Pharmaceuticals, Inc. Funding Information: M.M. has received personal fees from Janssen, Celgene, Amgen, Bristol-Myers Squibb, Sanofi, Novartis, and Takeda and grants from Janssen and Sanofi during the conduct of the study. E.T. has received grants from Janssen and personal fees from Janssen and Takeda during the conduct of the study, and grants from Amgen, Celgene/Genesis, personal fees from Amgen, Celgene/Genesis, Bristol-Myers Squibb, Novartis, and Glaxo-Smith Kline outside the submitted work. M.V.M. has received personal fees from Janssen, Celgene, Amgen, and Takeda outside the submitted work. M.C. reports honoraria from Janssen, outside the submitted work. M. B. reports grants from Janssen Cilag during the conduct of the study. M.D. has received honoraria for participation on advisory boards for Janssen, Celgene, Takeda, Amgen, and Novartis. H.S. has received honoraria from Janssen-Cilag, Celgene, Amgen, Bristol-Myers Squibb, Novartis, and Takeda outside the submitted work. V.P. reports personal fees from Janssen during the conduct of the study and grants, personal fees, and nonfinancial support from Amgen, grants and personal fees from Sanofi, and personal fees from Takeda outside the submitted work. W.W. has received personal fees and grants from Amgen, Celgene, Novartis, Roche, Takeda, Gilead, and Janssen and nonfinancial support from Roche outside the submitted work. J.S. reports grants and nonfinancial support from Janssen Pharmaceutical during the conduct of the study. V.L. reports funding from Janssen Global Services LLC during the conduct of the study and study support from Janssen-Cilag and Pharmion outside the submitted work. A.P. reports employment and shareholding of Janssen (Johnson & Johnson) during the conduct of the study. C.C. reports employment at Janssen-Cilag during the conduct of the study. C.F. reports employment at Janssen Research and Development during the conduct of the study. F.T.B. reports employment at Janssen-Cilag during the conduct of the study. The remaining authors have stated that they have no conflicts of interest. Publisher Copyright: © 2018 The AuthorsMultiple myeloma (MM) remains an incurable disease, with little information available on its management in real-world clinical practice. The results of the present prospective, noninterventional observational study revealed great diversity in the treatment regimens used to treat MM. Our results also provide data to inform health economic, pharmacoepidemiologic, and outcomes research, providing a framework for the design of protocols to improve the outcomes of patients with MM. Background: The present prospective, multinational, noninterventional study aimed to document and describe real-world treatment regimens and disease progression in multiple myeloma (MM) patients. Patients and Methods: Adult patients initiating any new MM therapy from October 2010 to October 2012 were eligible. A multistage patient/site recruitment model was applied to minimize the selection bias; enrollment was stratified by country, region, and practice type. The patient medical and disease features, treatment history, and remission status were recorded at baseline, and prospective data on treatment, efficacy, and safety were collected electronically every 3 months. Results: A total of 2358 patients were enrolled. Of these patients, 775 and 1583 did and did not undergo stem cell transplantation (SCT) at any time during treatment, respectively. Of the patients in the SCT and non-SCT groups, 49%, 21%, 14%, and 15% and 57%, 20%, 12% and 10% were enrolled at treatment line 1, 2, 3, and ≥ 4, respectively. In the SCT and non-SCT groups, 45% and 54% of the patients had received bortezomib-based therapy without thalidomide/lenalidomide, 12% and 18% had received thalidomide/lenalidomide-based therapy without bortezomib, and 30% and 4% had received bortezomib plus thalidomide/lenalidomide-based therapy as frontline treatment, respectively. The corresponding proportions of SCT and non-SCT patients in lines 2, 3, and ≥ 4 were 45% and 37%, 30% and 37%, and 12% and 3%, 33% and 27%, 35% and 32%, and 8% and 2%, and 27% and 27%, 27% and 23%, and 6% and 4%, respectively. In the SCT and non-SCT patients, the overall response rate was 86% to 97% and 64% to 85% in line 1, 74% to 78% and 59% to 68% in line 2, 55% to 83% and 48% to 60% in line 3, and 49% to 65% and 36% and 45% in line 4, respectively, for regimens that included bortezomib and/or thalidomide/lenalidomide. Conclusion: The results of our prospective study have revealed great diversity in the treatment regimens used to manage MM in real-life practice. This diversity was linked to factors such as novel agent accessibility and evolving treatment recommendations. Our results provide insight into associated clinical benefits.publishersversionPeer reviewe