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AICS Cafe

AICS Cafe is a place where the researchers in AICS can frankly discuss about their researches beyond their own disciplinary wall in order to collaborate with each other. We plan to have it twice a month regularly. We welcome all people including the promotion office and administration division of K computer in AICS.

  • Purpose : In order to promote the research collaboration beyond each of existing research disciplines, this seminar provides the discussion field for exchanging information, understanding neighboring researchers, and collaboration between each other.
  • Place: Workshop room (6th floor) at AICS
  • Lang : presentation in Japanese or English, the slide in English
  • Etc.: Please give your presentations clearly to researchers in other fields. Please do not hesitate to ask a question to the speakers.

The 131st AICS Cafe
Date and Time: Wed. Feb. 14, 2018, 15:30-16:30
Place: Workshop room (6th floor) at AICS

Title: TBA
Speaker: TBA

Presentation Language: TBA
Presentation Material: TBA

    Abstract:TBA

The 130th AICS Cafe (Special Meeting 2)
Date and Time: Thu. Feb. 1, 2018, 14:30-15:30
Place: Workshop room (6th floor) at AICS

Title: TBA
Speaker: Tatsuru Uchida(Kobe College, Professor emeritus)

Presentation Language: Japanese
Presentation Material: Japanese

    Abstract:TBA

The 129th AICS Cafe (Special Meeting 1)
Date and Time: Tue. Jan. 16, 2018, 15:30-16:30
Place: Workshop room (6th floor) at AICS

Title: The strong interaction, the mass of the universe and supercomputers
Speaker: Prof.Zoltan Fodor(University of Wuppertal,Germany)

Presentation Language: English
Presentation Material: English

    Abstract:

In particle physics, the strong interaction is the mechanism responsible for the strong nuclear force. It is described by a quantum field theory and due to its strength the underlying equations are strongly coupled. The only systematic way to solve them is by using leading edge supercomputers. Interestingly enough, the solutions to these equations answer many fundamental questions. They explain the mass of the visible universe. They tell us how the tiny mass difference between neutrons and protons are generated, which is the reason for the ignition of stars. These solutions might even help to answer the question about the origin of dark matter. The synergy between supercomputers and physics will be discussed in detail.

The 128th AICS Cafe
Date and Time: Wed. Jan. 10, 2018, 15:15-16:15
Place: Workshop room (6th floor) at AICS

Title: Stop-worrying and control your temper to make yourself feel and look good♪
Speaker: Yayoi Sakamoto (Rosewood - Communication support organization)

Presentation Language: Japanese
Presentation Material: Japanese

The 127th AICS Cafe (Joint seminar with University of Hyogo)
Date and Time: Tue. Dec. 19, 2017, 16:30-17:30
Place: Seminar room (1st. floor) at AICS

Title: Self-thinking and interaction in opinion formation
Speaker: Prof. Francesco Salvarani (Tenured researcher, Università degli Studi di Pavia, Italy)

Presentation Language: English
Presentation Material: English

    Abstract: Detail

We study a model which describes the evolution of the opinion in a closed community, by taking into account three main phenomena. The first one is the personal reasoning, the others are the binary exchanges of opinion between individuals and the effect of mass media. After introducing the model and explaining the sociological hypotheses on which it has been built, we will study some of its mathematical properties, with special emphasis to the formation of equilibrium and the effect of mass media.

The 126th AICS Cafe
Date and Time: Wed. Dec. 6, 2017, 15:30-16:30
Place: Workshop room (6th floor) at AICS

Title: Buzzword and Supercomputer
Speaker: Hiroya Matsuba (Team Leader for HPC Usability Research Team)

Presentation Language: Japanese
Presentation Material: English

    Abstract: Detail

Buzzwords, such as “cloud” and “big data”, should not always be ridiculed even in the science community. It is true that they often lack precise definitions or academic novelties, but I don’t think researchers should underestimate the possibility that such buzzwords gather people’s attention and some of the people will produce realistic values.
In this first presentation from the new HPC Usability Team at AICS café, I will talk how this team will increase the number of users of supercomputers, which is one of the missions of this team, by making use of the power of buzzwords. Fortunately, some of the recently spotlighted techniques are closely related to supercomputing. For example, modern AI techniques heavily depend on huge computing power. IoT also has relations with supercomputing in some particular applications. If we succeed to show attractive examples of supercomputing in such emerging areas, more people will have interested in supercomputers. This presentation covers our strategy to realize such situation.

The 125th AICS Cafe
Date and Time: Wed. Nov. 15, 2017, 15:30-16:30
Place: Workshop room (6th floor) at AICS

Title: The SCALE-LETKF regional weather data assimilation system: achievements and prospects
Speaker: Guo-Yuan Lien (Data Assimilation Research Team )

Presentation Language: English
Presentation Material: English

    Abstract: Detail

We have been developing the SCALE-LETKF system, utilizing a regional weather model known as the Scalable Computing for Advanced Library and Environment-Regional Model (SCALE-RM) and an ensemble data assimilation method known as the Local Ensemble Transform Kalman Filter (LETKF). The primary goal of the system is to make use of observational data obtained from an advanced weather radar, the Phased Array Weather Radar (PAWR), in numerical weather prediction (NWP). This new type of weather radar can observe heavy precipitation systems densely both in space and in time, providing an important data source for advanced weather monitoring; however, its effective use in high-resolution NWP is a frontier research topic. We investigate this rapid-update, high-resolution data assimilation problem using the SCALE-LETKF. We have also been applying the SCALE-LETKF system for an experimental near-real-time NWP system in Japan and surrounding area. We run 5-day weather forecast for this area every 6 hours in near real time using the K computer. This has been running stably and has provided important guidance on the performance of the model and the data assimilation settings. In addition, this talk will also discuss about the computational aspect of the SCALE-LETKF development and some ongoing issues and prospects of the system.

The 124th AICS Cafe
Date and Time: Thu. Nov. 9, 2017, 15:30-16:30
Place: Workshop room (6th floor) at AICS

Title: Evolution and challenges of quantum annealing technology
Speaker: Shu Tanaka (Associate Professor, Waseda Institute for Advanced Study, Waseda University/JST PRESTO Researcher )

Presentation Language: Japanese
Presentation Material: English

    Abstract: Detail

Research and development of quantum annealing, which is expected to perform combinatorial optimization processing at high speed and with high accuracy, has been actively advanced from three perspectives of hardware development, software development, and application search. To use a quantum annealing machine, we should perform the following steps. At first, by using the Ising model, we express the combinatorial optimization problem that we want to solve. Second, the Ising model obtained in the previous step is embedded in the qubit network of the quantum annealing machine. Next, we introduce a strong transverse magnetic field that expresses quantum fluctuation and gradually weaken it. We obtain a solution of the combinatorial optimization problem as a final state.

In this presentation, I will introduce the theoretical background of quantum annealing and previous studies. Also, studies on quantum annealing that I have done with collaborators will be shown. In addition, I will introduce the issues to overcome in order for quantum annealing to become a useful calculation technique.

The 123rd AICS Cafe
Date and Time: Wed. Nov. 8, 2017, 15:30-16:30
Place: Workshop room (6th floor) at AICS

Title: A statistical analysis of environmental flow patterns of tropical cyclone genesis
Speaker: Ryuji Yoshida (Computational Climate Science Research Team)

Presentation Language: Japanese
Presentation Material: English

    Abstract: Detail

Tropical cyclone genesis is one of the most challenging issues in tropical cyclone studies because of the complicated processes involved.
In the previous studies, the distinctive flow patterns found in tropical cyclone genesis are categorized.
However, a subjective analysis method was used in the categorize, and it is not easy to apply to statistical analysis.
Therefore, I newly developed an objective analysis method of low-level flow patterns.
By using this method, I have found that the intermediate scale environment mainly consists of shear line, confluence region of zonal winds, and easterly waves. Furthermore, I have revealed that the flow patterns are modulated by inter-seasonal oscillation. These results have largely contributed to advance the tropical cyclone genesis study by connecting largescale and mesoscale.

The 122nd AICS Cafe
Date and Time: Wed. Nov. 1, 2017, 15:30-16:30
Place: Workshop room (6th floor) at AICS

Title: Simulation study of nonlinear phenomena in plasmas
Speaker: Prof. Ryusuke Numata (Graduate School of SIMULATION STUDIES, University of Hyogo)

Presentation Language: English or Japanese
Presentation Material: English

    Abstract: Detail

Plasma, the fourth state of matter where constituent atoms are ionized, is very common in the universe. The goal of plasma physics is to understand the behavior of plasmas around the sun or planets and to realize a fusion power plant by confining high-temperature plasmas in a controlled manner.
In plasma, we observe rich varieties of nonlinear phenomena. For example, unique structures, such as loop-like magnetic fields on the solar surface, or zonal flows in the planetary atmosphere, are self-generated through complex dynamics. Those structures are also known to exist in fusion plasmas.
In this talk, I briefly review plasma physics as a nonlinear science, and introduce our recent study of the magnetic reconnection process, a typical nonlinear phenomenon in plasmas.