Händelser: Fysikhttp://www.chalmers.se/sv/om-chalmers/kalendariumAktuella händelser på Chalmers tekniska högskolaFri, 13 May 2022 11:06:34 +0200http://www.chalmers.se/sv/om-chalmers/kalendariumhttps://www.chalmers.se/sv/styrkeomraden/energi/kalendarium/Sidor/IPCC-Where-are-we-in-the-transitions.aspxhttps://www.chalmers.se/sv/styrkeomraden/energi/kalendarium/Sidor/IPCC-Where-are-we-in-the-transitions.aspxIPCC – Where are we in the transitions?<p>ONLINE, Zoom</p><p>​Welcome to a webinar organized by Chalmers University of Technology.  When: 17 May 2022, at 12:00-13:30. Place: Online. Platform Zoom. Last day to register 10 May. IPCC Sixth Assessment Working Group III report on Climate Mitigation: Where are we in the transitions?</p>​<div><span class="text-normal page-content"><div><a href="https://ui.ungpd.com/Surveys/b23d00d1-df45-40e1-a179-29304f983e26"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" />Register to the webinar</a><br /><a href="https://ui.ungpd.com/Surveys/877d3aa4-8892-4961-be08-fa94811d5888"><div style="display:inline !important"> </div></a><span style="background-color:initial"><span style="font-weight:700"><br /></span></span></div> <span style="background-color:initial"><span style="font-weight:700">​IPCC WG3 seminar.</span> IPCC released its Sixth Assessment Working Group III Report April 4, 2022.</span><div>This seminar aims to provide a review on some of the chapters of the IPCC AR6 WGIII report, and take a critical reflection of the report. What does the IPCC say about climate mitigation? What can we learn from IPCC-AR6 WGIII report? Are there any gaps in the IPCC-AR6 report that have not been addressed? How role does IPCC report play in the societal debate regarding what actions we should take? <br /><br /></div> <div></div> <div><span style="font-weight:700">Program:</span></div> <div><ul><li><span style="font-weight:700">Moderator: </span><span style="font-weight:700">Maria Grahn</span>, Associate professor in Energy Systems Analysis., Chalmers University of Technology </li></ul></div> <div><span style="font-weight:700">Speakers (and the chapters they are responsible for): </span></div> <div><ul><li><span style="background-color:initial"><span style="font-weight:700">Joana Portugal P</span></span><span style="background-color:initial"><span style="font-weight:700">ereira</span>, </span><span style="background-color:initial">Assistant professor, Federal University of Rio de Janeiro. Overview of WGIII, Summary to Policymakers and Chapter 4. Mitigation and development pathways in the near-to mid-term. </span></li> <li><span style="font-weight:700">Felix Creutzig</span>, Professor, Mercator Research Institute on Global Commons and Climate Change &amp; TUB Berlin, (Chapter 5. Demand, services and social aspects of mitigation). </li> <li><span style="font-weight:700">Sonia Yeh</span>, Professor of energy and transport systems, Chalmers University of Technology (Chapter 10. Transport in the subchapter “Scenarios from Integrated, Sectoral and Regional Models”).</li> <li><span style="font-weight:700">Fredric Bauer</span>, Associate Senior Lecturer in Technology and Society, Lund University (Chapter 11. Industry). </li> <li><span style="font-weight:700;background-color:initial">Oliver Geden</span><span style="background-color:initial">, Senior fellow, German Institute for International and Security Affairs (SWP), Assessment of carbon dioxide removal across WGIII.</span></li> <li><span style="background-color:initial"><b>Tomas Kåberger</b>, professor in Industrial Energy Policy, Director of AoA Energy. What role does the IPCC report play in the industry, authorities and other societal debates? ​<br /></span></li> <li><span style="background-color:initial"><b>Panel discussion</b>. Moderator Maria Grahn.</span></li></ul> <a href="https://ui.ungpd.com/Surveys/b23d00d1-df45-40e1-a179-29304f983e26"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" />Register to the webinar</a><br /><br style="background-color:initial" /><span style="font-weight:700;background-color:initial">Related:</span><br /></div> <a href="https://www.ipcc.ch/"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" />IPCC, <span style="background-color:initial">The Intergovernmental Panel on Climate Change ​</span></a><div><br /></div></span></div> ​​https://www.chalmers.se/sv/centrum/fysikcentrum/kalendarium/Sidor/GPC-Kollokvium-Bernhard-Mehlig.aspxhttps://www.chalmers.se/sv/centrum/fysikcentrum/kalendarium/Sidor/GPC-Kollokvium-Bernhard-Mehlig.aspxGöteborgs Fysikcentrum (GPC) kollokvium: Bernhard Mehlig<p>Wijkanders, Vera Sandbergs allé 5B</p><p></p><span style="font-size:16px"><strong>​</strong></span><span style="background-color:initial;font-size:16px"><strong>Om seminarieserien GPC Colloquium</strong></span><div>Vi startar om kollokvium-serien inom GPC (Göteborgs Fysikcentrum) men i ett annat format och på annan plats – fakultetsvåningen på Wijkanders.</div> <div>Olika talare från eller utanför Göteborg ger dig nya insikter om fysikens många aspekter och det kommer att finnas möjlighet att mingla med dina kollegor efteråt.</div> <div>Eftersom syftet är att dela kunskap och knyta kontakter har vi valt att inte erbjuda någon möjlighet att delta på distans – vi välkomnar alla att delta på plats! </div> <div><br /></div> <div><span style="background-color:initial"><span style="font-weight:700">FÖRELÄSARE</span>: Prof. Bernard Mehlig, Department of Physics, Gothenburg University</span><br /></div> <div><span style="font-weight:700">TITEL</span>: <span style="background-color:initial">Turbulent Aerosols</span></div> <div><span style="font-weight:700">SAMMANFATTNING</span>: <span style="background-color:initial">Turbulent aerosols are suspensions of droplets or solid particles in a turbulent gas, such as water droplets in the turbulent air of a cumulus cloud. The analysis of such highly non-linear and multi-scale problems poses formidable challenges. Laboratory experiments resolving the particle dynamics have only recently become possible, and direct numerical simulations of such systems are still immensely difficult.</span></div> <div>In this talk I describe recent progress in understanding the dynamics of turbulent aerosols. We formulated and analysed statistical models that  capture the relevant physics, that account for the statistical properties of the turbulent flow, and that allow systematic mathematical analysis using dynamical-systems theory. I summarise how this helps to understand fundamental mechanisms determining the particle dynamics: small-scale fractal clustering, caustic singularities, and anomalously large relative particle velocities. I highlight successes and failures of this approach, as well as the most important open questions.</div> <div><br /></div> <div><span style="background-color:initial">(Referens: K. Gustavsson &amp; B. Mehlig, Adv. Phys. 65 (2016) 1-57.)</span></div>https://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Licentiatseminarium-Moad-Al-Dbissi-220524.aspxhttps://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Licentiatseminarium-Moad-Al-Dbissi-220524.aspxMoad Al-Dbissi, Nukleär teknik<p>Raven and the Fox, conference room, Fysikgränd 3, Forskarhuset Fysik</p><p>​Titel på licentiatuppsats: Developments toward a novel methodology for spent nuclear fuel verification</p>​​<div><strong>Sammanfattning</strong>: <span style="background-color:initial">One of the tasks in nuclear safeguards is to regularly inspect spent nuclear fuel discharged from nuclear power reactors and verify the integrity of it, so that illegal removal and diversion of radioactive material can be promptly discovered. In the current project, which is a collaboration between Chalmers University of Technology and SCK CEN, a novel methodology for non-intrusive inspection of spent nuclear fuel is under development. The methodology consists of two main steps: 1) neutron flux and its gradient are measured inside spent nuclear fuel assemblies using small neutron detectors; and 2) the measurements are processed using an Artificial Neural Network (ANN) algorithm to identify the number and location of possible fuel pins that have been removed from the fuel assemblies and/or replaced with dummies. The use of small neutron detectors simplifies the inspection procedure since the fuel assemblies are not moved from their storage position. In addition, the neutron flux gradient measurements and its processing with the ANN algorithm have the potential for more detailed results. Different aspects have been investigated for the development of the methodology.</span><div>For the first step of the methodology, the concept of a new neutron detector has been studied via Monte Carlo simulations and it relies on the use of optical fiber-mounted neutron scintillators. The outcome of the computational study shows that the selected detector design is a viable option since it has a suitable size to be introduced inside a fuel assembly and can measure neutron flux gradients. Then, experimental work has been carried out to test and characterize two optical fiber-based neutron scintillators that can be used to build the detector, with respect to detection of thermal neutrons and sensitivity to gamma radiation.</div> <div>For the second step of the methodology, a machine learning algorithm based on ANN is studied. At this initial stage, a simpler problem has been considered, i.e., an ANN has been prepared, trained and tested using a dataset of synthetic neutron flux measurements for the classification of PWR nuclear fuel assemblies according to the total amount of missing fuel, without including neutron flux gradient measurements and without localizing the anomalies. From the comparison with other machine learning methods such as decision trees and k-nearest neighbors, the ANN shows promising performance.</div> <div><br /></div> </div> ​https://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Masterpresentation-Eleanor-May-220525.aspxhttps://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Masterpresentation-Eleanor-May-220525.aspxEleanor May, MPPHS fysik<p>PJ, seminar room, Kemigården 1, Fysik Origo</p><p>​Titel på masterarbete: Bayesian History Matching of Chiral Effective Field Theory in the Two-Nucleon Sector Följ presentationen online Lösenord: 902278</p><strong>​Sammanfattning:</strong><div><div>The accurate calculation of nucleon-nucleon scattering observables from first principles is an ongoing challenge within nuclear physics. Working within the framework of chiral effective field theory provides a method for calculating such observables. This is achieved through the construction of an effective Lagrangian that maintains the symmetries of quantum chromodynamics (QCD). In this thesis, truncation of the Lagrangian is performed using a modified Weinberg power counting, introducing a set of unknown low-energy constants at each order in the chiral expansion.</div> <div><br /></div> <div>Bayesian history matching is used to explore the leading order description of the nucleon-nucleon system. This is achieved through the iterative reduction of the four-dimensional parameter space, taking a Bayes linear approach. The history matching implementation is validated on the nuclear liquid drop model. Several novel methods of sampling are introduced within the implementation with the purpose of capturing correlations between parameters; The generation of ellipsoidal distributed samples is shown to be the most successful. History matching is subsequently applied to the proton-neutron scattering problem. We identify the subset of parameter space containing all low-energy constants that produce model outputs consistent with experimental two-nucleon scattering data, accounting for relevant sources of uncertainty. Non-implausible parameter volumes are obtained across a range of momentum regulator cutoffs. Finally, non-implausible samples are used to predict the deuteron binding energy. Results indicate that the inclusion of this observable within the history match could further constrain the volumes.</div> <div><br /></div> <div>The analysis performed in this thesis was successful in producing sets of non-implausible samples. Such sets can be subsequently used as a starting point for a full Bayesian analysis, with the aim of producing posterior probability distributions. For example, the samples can be used to initialise walkers within the Markov Chain Monte Carlo method.</div></div>https://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Masterpresentation-Yanuar-Rizki-Pahlevi-220609.aspxhttps://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Masterpresentation-Yanuar-Rizki-Pahlevi-220609.aspxYanuar Rizki Pahlevi, MPCAS<p>Nexus 4030, meeting room, Kemigården 1, Fysik Origo</p><p>​Titel på masterarbete: Deep Learning for Optical Tweezers: DeepCalib Implementation for Brownian Motion with Delayed Feedback</p><strong>Sammanfattning:</strong><div><div>Brownian motion with delayed feedback theoretically studied to take control of Brownian particle movement’s direction. One can use optical tweezers to implement delayed feedback. Calibrating optical tweezers with delay implemented is not an easy job. In this study, Deep learning technique using Long Short Term Memory(LSTM) layer as main composition of the model to calibrate the trap stiffness andto measure the delayed feedback employed, using the trapped particle trajectory asan input. We demonstrate that this approach is outperforming variance methods inorder to calibrate stiffness, also outperforming approximation method to measure the delay in harmonic trap case.</div></div> <div><br /></div>https://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Masterpresentation-Hannes-Bergstrom-och-Peter-Halldestam-220610.aspxhttps://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Masterpresentation-Hannes-Bergstrom-och-Peter-Halldestam-220610.aspxHannes Bergström och Peter Halldestam, MPPHS fysik<p>PJ, seminar room, Kemigården 1, Fysik Origo</p><p>​Titel på masterarbete: Optimization of tokamak disruption scenarios: avoidance of runaway electrons and excessive wall loads Följ presentationen online Lösenord: optimize</p><strong>​Sammanfattning:</strong><div><div>Research in the field of fusion science has been propelled by its potential to alleviate humanity's reliance on fossil fuels. </div> <div>One of today's most promising approaches to generating thermonuclear fusion energy uses magnetic confinement of hydrogen fuel in the plasma state. The tokamak concept, which has achieved the best fusion performance so far, is used in the two devices (ITER and SPARC) currently being constructed -- they aim to achieve a positive energy balance, thereby demonstrating the scientific feasibility of magnetic confinement fusion energy. </div> <div><br /></div> <div>A major open issue threatening the success of these tokamaks is plasma disruption. In these off-normal events the plasma loses most of its thermal energy on a millisecond timescale, exposing the device to excessive mechanical stress and heat loads. In addition, in the high-current devices currently under construction, one of the most important related problems is posed by currents carried by electrons accelerated to relativistic energies, called runaway electrons. If these were to strike the inner wall unmitigated, it may cause potentially irreversible damage to the device. The methods proposed to mitigate these dangerous effects of disruptions, such as massive material injection, are characterized by a large number of parameters, such as when to inject material, in which form and composition. This poses an optimization problem which involves a potentially high dimensional parameter space and a large number of disruption simulations. </div> <div><br /></div> <div>In this work, we have developed an optimization framework which we apply to numerical disruption simulations of plasmas representative of ITER, aiming to find initial conditions for which large runaway beams and excessive wall loads can be avoided. We assess the performance of mitigation when inducing the disruption by massive material injection of neon and deuterium gas. The optimization metric takes into account the maximum runaway current, the transported fraction of the heat loss -- affecting heat loads -- and the temporal evolution of the ohmic plasma current -- determining the forces acting on the device. </div></div>https://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Masterpresentation-Esmée-Berger-220610.aspxhttps://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Masterpresentation-Esm%C3%A9e-Berger-220610.aspxEsmée Berger, MPPHS fysik<p>PJ, seminar room, Kemigården 1, Fysik Origo</p><p>​Titel på masterarbete: Runaway dynamics in reactor scale spherical tokamak disruptions Följ presentationen online Lösenord: step</p><strong>Sammanfattning:</strong><br /><span style="background-color:initial"></span><div>One of the most promising concepts to achieve commercial fusion power, to date, is a toroidal magnetic confinement system centered around a tokamak. To aid the development, compact spherical tokamaks have long been proposed as component testing facilities. There is also an effort to design and construct spherical tokamaks suitable for energy production, with an example being the STEP program in the UK. One of the remaining obstacles for all reactor-scale tokamaks is so-called runaway electrons -- electrons accelerated to relativistic speeds. These can be generated during disruptions, which are off-normal events where the confinement of the plasma is rapidly lost. As runaway electrons can severely damage the machine walls, their production and mitigation has been extensively studied for conventional tokamaks. However, due to the disruption dynamics typically being different in spherical tokamaks, the existing results cannot directly be transferred to these more compact devices. Therefore, runaway dynamics in reactor-scale spherical tokamaks is investigated in this work, and we study both the severity of runaway generation during unmitigated disruptions, as well as the effect that typical mitigation schemes based on massive material injection have on runaway production. The study is conducted using the numerical framework DREAM (Disruption and Runaway Electron Avoidance Model) and we find that, in many cases, mitigation strategies are necessary if the runaway current is to be prevented from reaching multi-megaampere levels. Our results indicate that with a suitably chosen deuterium-neon mixture for mitigation, it is possible to achieve a tolerable runaway current and ohmic current evolution. With such parameters, however, the majority of the thermal energy loss happens through radial transport rather than radiation, which poses a risk of unacceptable localized heat loads.</div>https://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Masterpresentation-Linnea-Rensmo-220614.aspxhttps://www.chalmers.se/sv/institutioner/fysik/kalendarium/Sidor/Masterpresentation-Linnea-Rensmo-220614.aspxLinnea Rensmo, MPPHS Fysik<p>PJ, seminar room, Kemigården 1, Fysik Origo</p><p>​Titel på masterarbete: Characterization of HDPE using small and wide angle scattering</p><strong>Sammanfattning:</strong><div></div> <div><div>The importance of polymers in materials science can not be underestimated. Polymers are widely used within everything from clothing and  electronics to packages and paint. Tetra Pak uses the polymer high-density polyethylene, or HDPE, for their packaging solutions. The plastic material HDPE has the advantageous properties of being moldable and sturdy. To build understanding of what structures gives rise to these properties it is important to characterize the material. If the structure is known, it is perhaps possible to manufacture a similar material, in the future, that is not made from oil. This work focuses on the characterization of the material. The structures of HDPE are investigated with small and wide angle scattering.</div> <div style="font-weight:bold"><br /></div></div>https://www.chalmers.se/sv/styrkeomraden/material/kalendarium/Sidor/Chalmers-Sport-och-Teknologi-firar-10-ar.aspxhttps://www.chalmers.se/sv/styrkeomraden/material/kalendarium/Sidor/Chalmers-Sport-och-Teknologi-firar-10-ar.aspxChalmers Sport & Teknologi firar 10 år<p>Runan Chalmers Kårhus</p><p>​SAVE THE DATE: Material, Digitalisering, Biomekanik och Fluiddynamik – med tillämpningar inom idrotter som cykling, hästsport, innebandy, segling, skidåkning och simning. 6–7 september fyller Chalmers Sport &amp; Teknologi 10 år.</p>​<br /><span class="text-normal page-content"><span style="font-weight:700">​</span><img src="/SiteCollectionImages/Centrum/Sports%20and%20Technology/General/Chalmers_Sport_o_Teknologi_ordbild_en.png" alt="Sport Technology" class="chalmersPosition-FloatLeft" style="margin:5px;height:128px;width:155px" /><span style="background-color:initial"><span style="font-size:16px"><b>C</b><b>halmers Sport &amp; Teknologi</b> initierades 2012 som ett svar på den ökade efterfrågan på mer djuplodande teknisk forskning med tillämpningar inom idrott. Sedan dess har sportsrelaterad utbildning, forskning och innovation genomförts tillsammans med över 150 externa intressenter, bland annat ett stort antal företag, idrottsförbund och föreningar samt andra offentliga organisationer<b>.</b></span><br /><br /><span style="font-size:12pt"><img src="/SiteCollectionImages/20210701-20211231/hästhopp_S8A3210-5-4.jpg" alt="jumping" class="chalmersPosition-FloatLeft" style="margin:5px;height:139px;width:154px" /></span></span><div><div><div><span style="font-size:16px"><b>Idag är Chalmers </b>ett av Sveriges Riksidrottsuniversitet där elitidrottare kan kombinera sin idrott med studier.</span></div> <div><span style="font-size:16px">Under 10-årsjubileumssymposiet får du möjlighet att ta del av inspirerande seminarier och workshops med svenska och internationella talare om ”Sports and Sustainability, Data driven sports research, Innovation in sports and Education in sports &amp; technology”. </span></div> <div><span style="font-size:16px"><br />Programmet för Sport &amp; Teknologis 10 års-jubileum presenteras i juni.</span></div></div> <div><p class="MsoNormal" style="margin-bottom:15pt;line-height:16.5pt"><br /></p> <p class="MsoNormal" style="margin-bottom:15pt;line-height:16.5pt"><span style="font-weight:700">Läs mer:<br /></span><a href="/en/areas-of-advance/materials/Calendar/Pages/Ten-years-of-Sports-and-Technology-.aspx"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/ichtm.gif" alt="" /><span style="font-size:16px"> Sport &amp; </span><span style="font-size:16px">Teknologis</span><span style="font-size:16px"> 10 års jubileum </span></a><span style="font-size:16px">(engelska)</span><br /><a href="/en/centres/sportstechnology/Pages/default.aspx"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/ichtm.gif" alt="" /><span style="background-color:initial">C</span><span style="background-color:initial">halmers Sports &amp; Technology</span></a><br /><a href="https://www.facebook.com/ChalmersSportTeknologi/" style="font-weight:300;outline:0px"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" /><span style="font-weight:700">facebook.com/ChalmersSportteknologi</span></a><br /></p> ​</div></div></span>