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Cooperation and Value Creation in Community-based Workspaces
Development process of coworking
In recent years, working systems of individuals who do not necessarily have the same occupation or affiliation but interact and cooperate with each other according to the situation in organizations and local communities, as well as the workplaces that they share, have been attracting attention. This research is aimed to clarify the process of cooperation and value creation in such workplaces.
Research
The purpose of this study is to elucidate the process of cooperation and value creation in a community-type workspace. A community-type workspace is an open workspace where individuals share information and knowledge with other through communication, and create value through collaboration according to the situation. A coworking space is a typical example of such a place, and in recent years, it has been becoming more and more popular in Europe, the U.S., and the rest of the world. In the background, there is a movement of questioning the highly uniform interaction and cooperation among members in closed spaces, a system that is still dominant in organizations and local communities, and to achieve both individual autonomy and solidarity. This research is expected to provide knowledge that will contribute to the design and operation of such workspaces, as well as their organizational and social utilization, which are still largely unknown.
Tadashi Uda Associate Professor -
Environmentally Friendly Marine Biofouling Prevention Compounds Derived from Biomass
Toxic marine anti-biofouling agents against barnacles and other marine organisms are causing pollution to the marine environment, and it is necessary to develop safe alternatives. We have succeeded in creating potent and low-toxicity compounds by synthesizing biomass-derived compounds. Further optimization is also possible.
Research
The use of the ocean by mankind (e.g., ships and cooling pipes for power plants) is essential, but marine fouling organisms such as barnacles impairs the fuel efficiency of ships and obstructs the functions, for example by clogging. Organotin compounds have been used to prevent functional impairment, but their use has been banned due to their toxicity, and the development of alternatives is desired. We are focusing on compounds used by marine organisms such as nudibranchs to protect against fouling by other organisms. As a result of synthesizing the compounds, we found functional groups (anti-fouling units) that are important for anti-fouling. The functional group was introduced into inexpensive biomass derived from marine organisms in a short process, and when the synthetic product was tested for anti-fouling (cypris larvae of striped barnacles), they were found to have both very strong anti-fouling activity and very weak toxicity. We are currently conducting research on the synthesis of similar compounds and the addition of further functions.
Taiki Umezawa Associate Professor -
Community Development and Environmental Conservation through Interview Surveys
Consensus building based on diversity
Based on fieldwork in the Solomon Islands, Miyagi, and Hokkaido, we are studying the relationship between nature and local communities, and are conducting research on and implement the promotion of environmental conservation and community development from the bottom up. After the Great East Japan Earthquake, we have been conducting research in Ishinomaki City, Miyagi Prefecture, to support reconstruction efforts.
Research
We are conducting research to apply "interviews" to policies and activities. Local residents, researchers, and students collaborate to investigate people, nature, history, culture, and social issues in local communities, to identify issues, think of solutions, and consider the future of the region. We are practicing and applying the methods of interviewing and verbatim recording as tools for this purpose. We are researching the possibilities of qualitative research (interviews and verbatim recording) as a way of visualizing what cannot be seen in conventional quantitative research (statistics and questionnaires) and workshops, and to build relationships of trust.
Taisuke Miyauchi Professor -
Clarifying the Physical Constants of Electron Spin Control
Accelerating the research and development of next-generation electronic devices
Among various semiconductor properties, we have quantitatively clarified the previously unknown “spin-orbit interactions” of n-type quantum well structures based on InGaAs semiconductors, including gate voltage dependence. This achievement will be a seed for the development of next-generation spin devices.
Research
Existing semiconductor devices operate through the electric charge of electrons. In addition to the electric charge, an electron also has the other property of spin, which is a magnetic property. The electron spin in a solid can be aligned in a certain direction (Fig. 1a) or rotated about a specific axis (Fig. 1bc), depending on the situation. The key to realizing next-generation electronic devices is to control such electron spin in semiconductor devices. In this study, we used indium-, gallium-, and arsenic-based field-effect transistors (Fig. 2) and performed electrical measurements in a cryogenic environment (absolute temperature of 20 mK) using a dilution refrigerator (Fig. 3). In this way, we were able to precisely determine for the first time the spin-orbit interaction coefficient, which is necessary to control electron spin (Fig. 4).
Takaaki Koga Associate Professor -
Exploration of Marine Phytoplankton from Space
Development of techniques for classification exploration and quantification of phytoplankton in the ocean using satellites
We are developing a method to remotely survey floating microalgae (phytoplankton) in the ocean using earth observation satellites. We are currently examining a method to quantitatively observe the world’s largest number of taxonomic groups (11 groups) for remote sensing.
Research
Phytoplankton in the ocean is a primary producer that supports bioenergy production required for fish production, and the abundance ratios among different kinds of phytoplankton can be used as an indicator of different ecosystem structures (and thus different biological resources). It is expected that the application of satellite exploration technology will enable us to understand where, when, and how different ecosystem structures are fluctuating around the world, which will in turn enable efficient exploration, evaluation and management of biological and fishery resources.
Takafumi Hirata Specially Appointed Associate Professor -
Development of a Non-destructive CT-XRD Coupling Method and Its Application
Visualization of the microstructure of hardened cement
To develop innovative cement-hardening materials, we are devising a non-destructive integrated CT-XRD method, a novel measurement method combining the CT method to obtain geometric and spatial information on microstructures inside concrete with an accuracy of several microns, and a diffraction method to investigate hydrates and alterations in the region of interest.
Research
Concrete is structurally hardened by binding rock (aggregate) through a hydration reaction between cement and water. As a structural material, concrete is intended to withstand loading and certain weather/environmental conditions, but these may cause cracking of the concrete, which may progressively deteriorate due to strong acids and other chemical reactions caused by erosion and materials from the atmosphere, seawater and groundwater that come in contact with it. To stably use the social infrastructure for a long period of time, it is important to be able to see inside the internal structure of concrete with “bug eyes” and find any abnormalities that have occurred.
With the pioneering “non-destructive integrated CT-XRD method,” the sample is irradiated with high-intensity X-rays from synchrotron radiation to selectively visualize 3D structures from transmitted monochromatic X-rays at 25 keV. Energy-dispersive X-ray diffraction is also performed in specific regions of interest through multiple slit operations to identify hydrates (portlandite, calcite, etc.), their alteration and aggregate minerals.Takafumi Sugiyama Professor -
High-temperature Latent Heat Storage Microcapsules
Core (alloy latent heat storage material) ? shell (Al2O3) type latent heat storage microcapsules capable of high-density heat storage in the high temperature range of over 500?C
The latent heat storage method, which utilizes latent heat generated during the solid-liquid phase change, is attractive for its high-density heat storage capacity. Microencapsulation of latent heat storage material enables not only heat storage but also heat transport and heat control applications, and we have developed latent heat storage microcapsules that can be used in the high temperature range of over 500°C.
Research
An Al-base alloy with a melting point above 500°C was newly discovered as a latent heat storage material. By skillfully applying chemical conversion/oxidation treatment to the micro-particles of this alloy (approx. 20 μm or larger), we have succeeded in developing core (Al-base alloy) and shell (Al2O3) type latent heat storage microcapsules (Fig. 1). These microcapsules have high heat storage capacity of approximately five times that of solid sensible heat storage materials, and have excellent mechanical properties. Since the shell is made of Al2O3, it can also be treated as a ceramic particle. In other words, it is an epoch-making heat storage material of which the performance can be upgraded while maintaining the current use of ceramic sensible heat storage technology.
Takahiro Nomura Associate Professor -
Multimedia Artificial Intelligence Technology Reaching Social Implementation
Approaching the practical application of AI technology through industry-university collaborative research!
With this research, we are developing artificial intelligence technology for multimedia data, mainly images, video, music, and audio. We are handling data related to medical images, social infrastructure data, materials science and other fields, mainly through industry-university collaborative research.
Research
We are not only conducting the world's most advanced artificial intelligence research, but also promoting research in interdisciplinary areas and taking on the challenge of solving real-world problems. Specifically, in medical imaging research, we have collaborated with many medical institutions in Japan to build AI technology that surpasses human diagnostic accuracy. In medical and civil engineering research, we have built Explainable AI (XAI), which not only enables learning of small amounts of data, a challenge in AI research, but also enables explanations of judgment results, making the technology usable in the real world. In recent years, we have also developed human-centric AI technology that can make decisions like humans by introducing information strongly related to human interests, such as human brain activity and eye gaze data, into the AI learning process.
Takahiro Ogawa Professor -
Nonlinear Compensator That Can Be Implemented Without Sensors
Nonlinear compensator that can easily be added to PID control systems
Currently, PID control is used as the main control method in industry, but the PID control technique has a problem that the control accuracy deteriorates due to the influence of nonlinear terms such as friction and gravity. We have proposed a nonlinear compensator that can easily be added to PID controllers.
Research
Digital acceleration control (DAC) is a robust control technique for systems with nonlinear terms and modeling errors that are difficult to model. DAC is a very effective controller, but it cannot perform position control by itself because it controls the target acceleration value. Therefore, we have combined DAC with a general PID control system. This PID-DAC combined control system allows both robust position control and acceleration control. In addition, as a new nonlinear compensator that can easily be added to PID controllers without sensors, we propose two controllers: the PID-DA0 control system, which sets the target acceleration value of the control object to zero, and the PID-DJ0 control system, which sets the target acceleration value to zero. Both controllers can easily be added to existing PID controllers without additional sensors, so they have the great advantage of improving system performance sensorless.
Takanori Emaru Associate Professor -
Electrochemically Responsive Organic Dyes
From electrochromism to multiple responses (fluorescence, circularity)
Based on cationic organic dyes, which allow easy control of color tone, we offer a group of materials that can respond in multiple ways, including fluorescence and optical rotation (circular dichroism). This technology is designed to suppress the decomposition process of reduced species, and the bi-stability of oxidized and reduced species is such that exchange does not occur, even when they are mixed.
Research
Electrochromism is a general term for compounds that change their color tone in response to changes in external electrical potential. As materials that can undergo reversible color changes, they are attracting attention as light control materials for smart windows and display functions for electronic paper. Materials of which not only the color tone, but also fluorescence, optical rotation (circular dichroism), etc. can be changed, enable tailor-made responses according to the application.
With this technology, we provide a group of substances with multiple responses based on cationic organic dyes of which the color tone can easily be controlled. The reduced species of cationic dyes are generally reactive, and the repeatability of the response is low, but with this technology, the decomposition process of the reduced species is suppressed by incorporating two cationic moieties. The bi-stability of the oxidized and reduced species, in which no exchanges occur, even when they are mixed, makes it possible to apply this technology to high-density recording materials.Takanori Suzuki Professor -
A method to evaluate radio wave propagation characteristics of in-vehicle wireless access services by large-scale electromagnetic field analysis
Toward optimal design of wireless environments
We have conducted research in various fields where radio waves are applied, including the evaluation of complex and special propagation environments in airplanes and passenger railroad cars, internal exposure of the human body to radio waves, electromagnetic interference evaluation and mechanism estimation regarding body medical devices implanted in the body, and evaluation of electromagnetic field leakage in wireless power supply devices for electric vehicles.
Research
The radio propagation environment inside a vehicle is a special environment that differs from the conventional propagation model due to multiple reflections caused by the surrounding metal and the presence of fixtures and passengers inside. It is therefore necessary to evaluate the characteristics of radio wave propagation, including the effects of absorption and scattering of radio waves by the bodies of passengers, to estimate the quality of the wireless connection under actual operational conditions. However, it is difficult to evaluate the propagation characteristics by actual measurement or simple numerical analysis (e.g., ray tracing). This study addresses modeling of the propagation environment in vehicles, which has been difficult in the past, and realizes a simulation method in a very large analysis space by using a supercomputer.
Takashi Hikage Associate Professor -
Super-hierarchical Structure Imaging Through the Combined Use of Neutrons and X-rays
Non-destructive imaging of unknown information over a wide range of scales using multi-quantum beams
Pulsed neutron transmission spectroscopy imaging is attracting attention as a method of non-destructive visualization of information that cannot be seen with other microscopic methods, and when it is combined with other quantum beams such as X-rays, it is possible to visualize information that cannot be seen with images alone.
Research
Hokkaido University’s laboratory facilities, where small accelerators are used, have a history of nearly half a century, and are attracting worldwide attention as pioneering facilities. We mainly produce pulsed neutron beams, and the transmission spectra obtained using these beams enable us to map information on crystal structure, microstructure, internal stress and temperature on a two-dimensional real image as a distribution map of the entire sample. We also use X-ray CT which can measure the three-dimensional structure of the inside of an object, and analyze the combined results from neutrons and X-ray studies to synergistically understand the interior information of an object. In the figure, shown as synergistic imaging based on information from neutrons and X-rays, information on elements that cannot be individually obtained is mapped on the inside structure shown on the X-ray CT image. X-ray CT shows the presence of wires in an Al cylinder, but when neutron information is added, we can see that each wire is a different material.
Takashi Kamiyama Professor -
Development of Reagents for Highly Efficient Transfection of siRNA into Immune Cells and Their Application to Cancer Immunotherapy
Development of next-generation drug delivery systems
We have developed a reagent (YSK12-MEND) to introduce siRNA into immune cells with high efficiency. If siRNA is introduced into immune cells using this reagent, the expression of immunosuppressive genes can be reduced with high efficiency, and thus it is expected to be applied to cancer immunotherapy using immune functions.
Research
We have developed YSK12-MEND, a reagent that can efficiently transfect siRNA, a gene expression inhibitor, into mouse and human immune cells. By using the novel reagent, the efficiency of siRNA transfection into mouse dendritic cells has improved more than 10-fold compared to the commercial product (Lipofectamine RNAiMAX). It is known that the function of immune cells is suppressed by cancer cells in cancer patients, although humans have an immune function to fight cancer cells. siRNA delivery using YSK12-MEND can efficiently suppress the expression of immunosuppressive genes in immune cells, which will enable humans to fight cancer cells with their own immune function. YSK12-MEND is expected to be one of the promising candidates for this purpose.
Takashi Nakamura Assistant Professor -
Applied Research on Content Tourism
International comparative study on the propagation and acceptance of culture through content tourism and its application to the planning of tourism town planning measures
We are conducting an international comparative study of content tourism from the perspective of the propagation and reception of pop culture to clarify the role that such tourism plays in understanding others. The knowledge gained through this research is also returned to the fields of tourism and urban planning in the form of specific measures.
Research
Through this research, we are conducting an international joint research project on content tourism (the act of actually visiting a place that is given meaning by a “story” or “work” and its constituent elements, and experiencing the relevant content) with the following three objectives:
First, we will clarify the role that such tourism plays in understanding others by rethinking content tourism from the perspective of the propagation and receipt of pop culture. Secondly, based on this, we will consider how to create a model exchange-oriented tourism town with content at its core. Thirdly, we will focus on the East Asian region, where Japan's geopolitical situation calls for international mutual understanding, and consider the possibilities and challenges that content tourism, triggered by Japanese content, has for Japan's cultural security.Takayoshi Yamamura Professor -
Gel that is Stronger Than Steel
Soft and tough composite material
By conjugating glass fiber and self-healing gel, we have achieved a gel that is stronger than carbon fiber-reinforced plastic (CFRP). Since the base material is a gel, it is as flexible as rubber against bending, but tougher than CFRP against tearing, making it difficult to break.
Research
The glass fiber composite gel we have developed exhibits unbreakable, untearable and tear-resistant properties. Generally speaking, CFRP and glass fiber reinforced plastic (GFRP) are widely used as composite materials. Similar to these fiber-reinforced plastics, fiber-reinforced gels are hard and resistant to tension because of the characteristics of the fibers, while being soft and flexible on bending because of the characteristics of the gel. The self-healing polyampholyte (PA) gel used as the base material is also strong as such thanks to its ability to dissipate a large amount of energy against deformation. Since the gel is flexible, when it is combined with fiber, local distortions can be transmitted through the fiber to the distant base material, resulting in large energy dissipation of the entire material, meaning that it is remarkably strong.
Takayuki Kurokawa ProfessorPh. D -
High Strength Gel That Spontaneously Bonds Strongly with Bone Tissue
Development of a safe, high-strength bonding method between wet materials and bone, which has been difficult to achieve so far, by utilizing bone healing in living organisms
In answer to the issue of in vivo fixation by applying the much anticipated high-strength hydrogel as a next-generation artificial cartilage or cartilage tissue regeneration scaffold material, we have developed a simple, non-toxic, high-strength adhesion method using hydroxyapatite, an inorganic component of bone tissue.
Research
The high-strength, high-toughness double-network gel (DN gel) previously developed by our group has excellent properties such as low wear on cartilage and induction of cartilage tissue regeneration in a natural joint, and is being studied for application as an artificial cartilage material and cartilage regeneration induction material. On the other hand, it is difficult to fix and maintain such a gel in a natural joint, which has been a major issue with the practical use of this material. In this study, we developed a fixation method that allows bone tissue regeneration to progress spontaneously into the gel and adhere firmly by compounding hydroxyapatite (HAp), the main inorganic component of bone tissue, to the surface layer of the DN gel. In addition to excellent mechanical properties and cartilage regeneration ability, the realization of non-toxic in vivo adhesion to bone is a great step forward toward the practical application of DN gel for joint treatment.
Takayuki Nonoyama Associate Professor -
Communication-avoidant Matrix Calculation Algorithm
Research and development of algorithms suitable for massively parallel computers
With the spread of massively parallel computers, it has become increasingly important to reduce the communication time associated with parallel computation. In this research, we aim to improve the performance of matrix computation algorithms by using an approach called “Communication Avoiding (CAA).”
Research
With parallel processing using large-scale parallel computers, the data communication time is often more important than the computation time. In particular, the large communication latency (the cost incurred regardless of the amount of data to be communicated) has become a problem, and there is a strong need to reduce the communication frequency (communication avoidance). We are reviewing existing matrix computation algorithms from the viewpoint of communication avoidance, and are researching and developing new algorithms for massively parallel computers that reduce the communication frequency.
Takeshi Fukaya Associate Professor -
Boundary Element Analysis Framework and Distributed H-matrix Method
Realizing cutting-edge, large-scale, high-precision analysis
We have developed a software framework for high-performance boundary element analysis in a parallel computing environment. We have also developed a distributed parallel H-matrix library, which is effective to accelerate a BEM analysis, and evaluated its performance on programs in various applications.
Research
In this study, we developed a parallel boundary element analysis framework as part of the JST CREST project on “Application Development and Execution Environment with Automatic Tuning Mechanism.” By using this framework, it is possible to develop boundary element analysis programs for large-scale parallel computing systems with a small programming cost. We also developed a library of H-matrices, which approximates dense matrices with less data using low-rank approximation. This library can be used for analysis of N-body problems in addition to boundary element analysis, and is already being used for earthquake simulation on supercomputers. There is no other H-matrix library that supports hybrid parallel processing utilizing multiple threads and processes, and this is a unique feature of this research.
Takeshi Iwashita Professor -
Hydrogenation with Homogeneous Palladium Nanoparticle Catalyst
Selective synthesis of cis-alkenes and amines
cis-Alkenes and amines, which are useful as raw materials for pharmaceuticals, agricultural chemicals and other chemical products, can be synthesized efficiently through hydrogenation of alkynes, organic nitro compounds and azides. The originally developed homogeneous palladium nanoparticles can be stored in solution for longer than a year and are easy to handle in air.
Research
We have found that homogeneous palladium nanoparticles can be obtained by treating palladium acetate with potassium tert-butoxide or sodium borohydride in the presence of alkynes (Fig.1). The nanoparticles can be stored in solution for longer than a year and are easy to handle in air. They exhibit excellent performance as hydrogenation catalysts and can efficiently synthesize cis-alkenes (2) and amines (4 and 6) from alkynes (1), organic azide compounds (3) and aromatic nitro compounds (5), respectively. They have excellent cis-alkene selectivity and functional group tolerance (no loss of the ketone, aldehyde, or benzylic hydroxy group, etc.). The catalytic activity is extremely high; the reaction proceeds quickly using only 1/1000 to 1/5000 equivalent of palladium of the substrate (raw material). It also has excellent economic efficiency and convenience, and we are examining the possibility of commercializing it in cooperation with companies.
Takeshi Ohkuma Professor -
Semiconductor Precision Processing Technology
Low-damage and controllable semiconductor etching technology using electrochemical reactions
A semiconductor etching technique using electrochemical reactions was developed to reduce damage and achieve precise processing control in the depth direction compared with conventional methods, and was applied to the gate recess processing of AlGaN/GaN heterostructure transistors to realize normally-off transistors.
Research
The etching process of semiconductor surfaces is one of the essential steps in the fabrication of semiconductor devices such as transistors. In this laboratory, we have developed an etching method that is superior to conventional dry etching methods in terms of both depth control and damage suppression, by utilizing electrochemical oxidation and dissolution reactions on semiconductor surfaces. As a result of applying the method to AlGaN/GaN heterostructures, which are considered to be promising power transistor materials, it was revealed that the etching process can be self-stopped at the desired processing depth by optimizing the electrochemical conditions, thus eliminating the need for an etching stop layer, which had been essential in prior technologies, and enabling precise control of the transistor threshold in a simpler way. In addition, the etched surface by this method has less processing damage than the dry-etched surface, and is expected to be a promising method for improving transistor performance.
Taketomo Sato Associate Professor
