糖心视频

Development of a wide-field X-ray monitor for the search for electromagnetic counterparts of gravitational wave sources II (2021-2023) (Representative: Professor Takanori Sakamoto Department of Physical Sciences; Co-researcher: Assistant Professor Motoko Serino, Department of Physical Sciences Mathematics)

On August 17, 2017, an electromagnetic counterpart of gravitational waves from the merger of neutron stars was discovered, heralding the dawn of gravitational wave astronomy. From this electromagnetic counterpart, we observed kilonova radiation, which is radiation from unstable atomic nuclei produced by fast neutron capture reactions, which are essential for the synthesis of heavy elements, and gamma-ray bursts that are thought to be associated with the gravitational wave source. As the era of ground-based gravitational wave detectors LIGO, Virgo and KAGRA to detect gravitational waves from celestial bodies with the highest sensitivity approaches, we will study and develop a wide-field soft X-ray monitor using a Japanese-made flying observation instrument that can explore the electromagnetic counterpart. The accuracy of the direction of arrival of gravitational waves determined by gravitational wave detectors is several tens to hundreds of square degrees, so it is essential to have an observation device that can observe a large area of the sky at once with high sensitivity. In addition, the wavelength of X-rays has the advantage that it is easier to explore unidentified celestial bodies because the celestial bodies are not crowded with objects compared to visible light. To achieve this goal, we aim to realize a high-sensitivity, wide-field-of-view X-ray telescope using an optical system called "Lobster Eye" and an X-ray imaging element on a 3U CubeSat.

Creation and control of novel phase transition phenomena in multi-degree-of-freedom frustrated systems (FY2021-2023) (Representative: Nobuo Furukawa, Professor, Department of Physics and Mathematics; Co-researcher: Tomoki Hirosawa, Assistant Department of Physical Sciences)

Electrons have microscopic electric charges and magnetic moments, and in solid materials there is a strong interaction between them. When the temperature is lowered, the electric charges and magnetic moments are frozen and aligned, and then they are combined to form macroscopic electric charges and magnetic moments that can be observed. For example, iron becomes a ferromagnetic material (permanent magnet) at temperatures below 770°C, because the magnetic moments of electron spins are aligned macroscopically below this temperature.
Conversely, if a mechanism that prevents such alignment exists, the expression of macroscopic degrees of freedom becomes unstable. Furthermore, by controlling this mechanism using external fields (electric fields, magnetic fields, pressure, etc.), a phenomenon known as giant external field response occurs, in which the state of the material changes significantly in response to a small external field.
In this research, we study the destabilization of states using a mechanism called frustration, aiming at fundamental research into large external field response and quantum control.

Detection of molecular states generated in cold Rb atomic gas (FY2021-2023) (Representative: Haruka Maeda, Professor, Department of Physics and Mathematics; Contributor: Kenta Kitano, Assistant Department of Physical Sciences)

A cooled Rydberg atomic gas, which is generated by irradiating an excitation laser onto Rb atomic gas that has been laser-cooled to about 150 μK and trapped in a magneto-optical trap (MOT), is known to be a unique mesoscopic quantum many-body system in which long-range interactions based on dipole-dipole forces determine the physical and chemical properties of the system. Multi-Rydberg atomic molecules and clusters, which are expected to exist in the gas, are one of the manifestations of the unique many-body effect, and their detection experiments are considered to be an interesting research topic. At present, while there have been several reports of the detection of molecules consisting of two Rydberg atoms (Rydberg atom pairs), there have been no systematic observations of so-called cluster states consisting of more than two Rydberg atoms, and this project aims to detect such states.

Development of corporate valuation methods based on mathematical modeling of corporate financial structures (FY2021-2023) (Representative: Associate Professor Takashi Yamanaka Department of Mathematical Sciences)

Financial institutions are required to provide smooth loans to companies and provide continuous management support. To achieve such management support, a method for assessing bankruptcy risk that takes into account the various management difficulties that borrowers may face is necessary. However, the current bankruptcy risk assessment method, known as the structural approach, focuses mainly on bankruptcies due to insolvency and does not comprehensively capture various bankruptcy factors such as cash flow difficulties. Therefore, this project aims to develop an assessment method that comprehensively captures various bankruptcy factors such as insolvency as well as insolvency. Currently, we are extracting the characteristics of the time series structure of financial and non-financial data of bankrupt companies and building a mathematical model that represents the occurrence of bankruptcy. We are also working on developing a method to predict the number of bankruptcies. Using statistical and machine learning models, we are analyzing the impact of changes in a company's management environment on the frequency of bankruptcy.

Development of Efficient Molecular Conversion Using Catalysts (FY2021-2023) (Representative: Professor Ryo Takeuchi, Department of Chemistry and Biological Science)

Modern civilization is supported by various organic molecules. From pharmaceuticals that protect life and health to functional organic molecules that support the latest technology, organic synthetic chemistry is required to provide organic molecules with desired structures. What these challenges have in common is the realization of high atom efficiency and step economy. In order to realize efficient molecular conversion from easily available organic molecules to more complex skeletons, there are high expectations for the development of new catalytic functions for transition metal complexes. In this research, in order to meet these expectations, we will focus on the following three themes (1) to (3) to enable efficient molecular conversion to useful organic molecules using catalysts: (1) Synthesis of optically active organic molecules (2) Synthesis of new aromatic heterocyclic compounds that are expected to be functional molecules (3) Development of carbon chain elongation reactions from unsaturated hydrocarbons, which are versatile chemical raw materials. We will conduct integrated and comprehensive research by relating these themes to each other.

Analysis of higher biological functions using animals (2021-2023) (Representative: Professor Hirata Fuzo Department of Chemistry and Biological Science Co-researcher: Assistant Department of Chemistry and Biological Science)

Living organisms have higher-order functions such as perception, memory, learning, emotion, and judgment. The nervous system makes these functions possible. So how is the nervous system formed and does it perform these functions? We are elucidating the higher-order functions of the nervous system using the tropical fish called zebrafish as a model. From behavioral experiments using zebrafish, we have revealed that a single chemical reaction changes the protein dynamics in synapses (the connection between nerve cells), causing behavioral changes in animals and enabling them to adapt to their environment. In addition, we have used the genome editing technology CRISPR/Cas9 to create fish with various higher-order dysfunctions and to elucidate the mechanisms of pathological onset. We have created fish that develop epileptic seizures due to brain hyperexcitation, and by screening compounds that alleviate the symptoms, we are creating drugs to improve epilepsy. Through these brain science researches, we will contribute to humans living healthy and fulfilling lives.

Research on wireless power transmission devices for automated guided vehicles (FY2021-2023) (Representative: Hirokazu Matsumoto, Associate Professor, Department of Electrical Engineering and Electronics Contributor: Yuki Sato, Assistant Professor Department of Electrical Engineering and Electronics)

Wireless power transmission technology is a technology that allows electronic devices to be charged without connecting cables. Because it allows for easy charging, it is becoming increasingly popular as a charger for mobile phones. Its major feature is that it can transmit power to moving objects. Current electric vehicles have a short driving range, long charging times, and expensive, heavy on-board batteries, which are obstacles to their widespread use. Wireless power transmission technology is thought to be one way to solve these problems.
The three-phase wireless power transmission system we have proposed is composed of a set of three phase coils, each of which has a different current flowing through it, and power is supplied by a three-phase inverter. In this system, the coils can be installed close together because the magnetic fields of adjacent coils are strengthened, and power can be transmitted seamlessly, making it suitable for transmitting power to moving objects. In this research project, we aim to realize this system as a charging device for automatic guided vehicles used in factories and logistics centers, and to achieve highly efficient and stable operation.

Development of technology for evaluating the long-term reliability of solar cells (FY2021-FY2023) (Representative: Yasuaki Ishikawa, Associate Professor Department of Electrical Engineering and Electronics Contributor: Itaru Raifuku, Assistant Professor Department of Electrical Engineering and Electronics)

The heart of a photovoltaic power generation system is the solar cell module, and each module has an output of several hundred watts, and currently a huge number of solar cell modules are produced and installed. In order to manage the amount of power generated by solar power generation, it is necessary to manage and operate each solar cell module to ensure that it is outputting electricity stably without any particular deterioration. This project aims to develop electroluminescence (EL) technology that can accurately diagnose whether a solar cell module is deteriorating or not in the environment in which the solar cell module is installed. The EL method detects the light generated by injecting a current into the solar cell module, and it is possible to evaluate the characteristics as a two-dimensional image by using a special camera. For crystalline silicon solar cell modules, which account for 90% of all solar cell modules, we are using EL technology to extract electrical characteristics, improve the accuracy of defect detection, and develop a method to identify degradation modes.

Research on the growth of single-crystal iridium thin films using chemical vapor deposition (FY2021-FY2023) (Representative: Professor Atsushi Sawabe, Department of Department of Electrical Engineering and Electronics)

Diamond has excellent properties such as low dielectric constant, high carrier mobility, and high dielectric breakdown field strength, and has a high performance index as a semiconductor material, making it a promising candidate for next-generation power devices. Since establishing a method for producing heteroepitaxial diamond, we have been working on increasing the size of diamond substrates and improving the quality of diamond by using a selective growth method that limits the diamond growth area. Furthermore, cost reduction is essential for practical use. Heteroepitaxial diamond is produced by producing an iridium thin film on a single crystal substrate using physical vapor deposition, and then seeding diamond and growing the diamond film on the surface using chemical vapor deposition, with each step being carried out in separate equipment. In order to reduce costs by introducing a unified growth method and consolidating equipment, this project aims to establish a process for producing single crystal iridium films using chemical vapor deposition from organometallic raw materials.

Development of a highly efficient heating system using functional ice slurry (2021-2023) (Representative: Professor Hiroyuki Kumano Department of Mechanical Engineering Co-researcher: Assistant Professor Takashi Morimoto, Department Department of Mechanical Engineering)

Ice slurry, a solid-liquid two-phase fluid of fine ice and water or an aqueous solution, has a large heat storage density that utilizes the latent heat of ice, and high heat exchange performance due to its latent heat and fluidity. Until now, ice slurry has been used for the purpose of "cooling" objects, but in recent years, its use for the purpose of "heating" objects has attracted attention. However, the advantages of using ice slurry as a heating medium, such as improved heat exchange rate, have not been quantitatively demonstrated. Another issue is that a frozen layer is formed when ice slurry is cooled, which becomes a factor that inhibits heat transfer. In this research project, we quantitatively clarify the heat exchange rate when ice slurry is used as a heating medium. We also propose a new ice slurry that has functions such as suppressing the formation of a frozen layer by clarifying the basic properties of ice slurry with various additives, including antifreeze proteins.

Development of multi-scale stress and strain analysis technology for advanced materials using image measurement technology (FY2021-FY2023) (Representative: Professor Satoshi Yoneyama Department of Mechanical Engineering Contributor: Assistant Professor Keisuke Iizuka Department of Mechanical Engineering)

To reduce the weight of various machines and structures such as automobiles and aircraft, the use of multi-materials is progressing, and the use of carbon fiber reinforced plastics (CFRP) and high-tensile steel is increasing. To further reduce the weight of these materials, it is necessary to clarify the mechanisms of deformation and fracture of these materials and to enable highly accurate fracture prediction. In this project, we will develop a technique to measure the strain of high-tensile steel and CFRP at various scales using image measurement techniques such as digital image correlation (DIC), and develop a technique to evaluate the material properties and stress distribution using the measurement results. Specifically, we will conduct research on (1) identification of the stress-strain relationship and stress distribution evaluation after necking of high-tensile steel, (2) development of a strain evaluation technique and evaluation of fracture behavior of rubber materials for tires, (3) development of a technique to measure strain inside CFRP using three-dimensional digital image correlation (DVC), (4) development of a technique to measure strain at the fiber and resin interface using global DIC, and (5) inverse problem analysis of material properties using the virtual field method.

Development of a new material strength evaluation method using X-ray diffraction (FY2022-FY2024) (Representative: Associate Professor Shota Hasunuma Department of Mechanical Engineering Co-researcher: Assistant Professor Tomoyuki Hayase Department of Mechanical Engineering)

The mechanical properties of surface modification layers, such as those created by shot peening or thermal spraying, are different from those of the base material. However, the thickness of the surface modification layer is only a few tens of micrometers, and conventional methods cannot grasp the mechanical properties. To make this possible, it is necessary to measure local stresses about 10 μm from the surface during material testing. In addition, since fatigue fracture occurs from stress concentration areas, it is important for safety to evaluate the local stresses that occur in stress concentration areas with high accuracy. However, it is difficult to evaluate the stress with high accuracy when repeated plastic deformation occurs and repeated hardening occurs. X-ray diffraction is a method for measuring stress from the diffraction of X-rays, and it is possible to measure local stress. Therefore, the purpose of this study is to develop a new material strength evaluation method using X-ray diffraction. We developed a method for measuring stress using X-ray diffraction during material testing, which makes it possible to evaluate the mechanical properties of the surface modification layer and the local stress in the stress concentration area. By developing an unprecedented material strength evaluation method like the above, we will contribute to improving the safety of machines and structures.

Research and development on reducing high-frequency noise (FY2023-FY2025) (Representative: Associate Professor Ryosuke Suga, Department of Electrical Engineering and Electronics)

The number of devices that handle relatively large amounts of high-frequency power, such as wireless power transmission, electric vehicles, and automotive radar, is increasing. While these devices enrich our lives, they also emit unnecessary radio waves that can cause other electronic devices to malfunction. In order to prevent the deterioration of the radio environment, radio wave absorbers and shielding materials are required, and in recent years, extremely thin and lightweight radio wave absorbers have been proposed, in which metal elements of about the wavelength are periodically arranged on the surface of a dielectric substrate. Traditionally, electromagnetic field simulations, which require a great deal of time and cost, have been used to design these radio wave absorbers. In this research, we are conducting research and development with the aim of designing a structure that can achieve the desired absorption characteristics of these radio wave absorbers using only simple calculations.

Development of quantitative optical phase imaging technology that is robust to environmental changes (FY2023-FY2025) (Representative: Assistant Professor Tomohiro Maeda Department of Electrical Engineering and Electronics; Co-researcher: Professor Hideyuki Tonobayashi, Department of Department of Electrical Engineering and Electronics)

Since the phase of a light wave contains information about the path that the light wave has taken, the optical phase distribution shows subtle unevenness of an object and slight differences in the composition of biological tissue. Phase-shifting digital holography (PSDH), an optical phase measurement technology that uses the interference of light waves, is capable of calculating optical phase distributions quantitatively with high precision, and has been attracting attention in recent years in areas such as industrial product inspection and biological tissue measurement. Calculating PSDH requires multiple interference fringes obtained by applying a phase shift between two interfering light waves, and various phase-shifting methods have been investigated to date.
We have proposed a completely new phase shift method that utilizes the interesting phenomenon that a checkerboard diffraction grating replicates light waves. In the proposed technology, multiple interference fringe images required for calculating PSDH can be acquired all at once by uniformly irradiating a replica of the object light generated by diffraction with a reference light. Furthermore, since the effect of replication does not depend on the position of the diffraction grating, it is also robust against fluctuations in the positional relationship of optical elements. In this research project, we aim to establish an optical phase measurement technology that is robust against temporal and spatial fluctuations through the fabrication of prototype diffraction gratings and evaluation of phase measurement accuracy.

Past Research Projects

• 2022 CAT Research Project
• 2021 CAT Research Project
• 2020 CAT Research Project
• 2019 CAT Research Project
• 2018 CAT Research Project

Related information

• Reporting Session (2018)
• Reporting session (2009-2015)
• Project Introduction (2013~)
• Project Introduction (1997~)