May 2024 Vol. 22 No. 5

View from the Top

• Yukari Tsuji, Senior Vice President, Head of NTT Information Network Laboratory Group

  

  Abstract
  NTT Information Network Laboratory Group promotes research and development (R&D) of communication networks and innovative environmental and energy technologies to create a sustainable and prosperous society. Focusing on three pillars of the Innovative Optical and Wireless Network (IOWN), robust networks, and environment and energy, the laboratory group aims to contribute to building a sustainable infrastructure of an information society and provide new value. We asked Yukari Tsuji, senior vice president, head of NTT Information Network Laboratory Group, about the laboratory group’s R&D strategy and her mindset as a top executive.

Front-line Researchers

• Doohwan Lee, Senior Distinguished Researcher, NTT Network Innovation Laboratories

  

  Abstract
  With the advent of smartphones, mobile communications have rapidly become popular. Fifth-generation mobile communications system (5G) services, which feature high speed, large capacity, low latency, and simultaneous connection to multiple terminals, are spreading, and the 3rd Generation Partnership Project (3GPP), an international standardization organization, has begun initial discussions on 6G. The technological foundation for the advancement of mobile communications is wireless transmission technology. Doohwan Lee, a senior distinguished researcher at NTT Network Innovation Laboratories, and his colleagues achieved the world’s first high-capacity wireless transmission of 1.44 Tbit/s using the sub-terahertz band. We interviewed him about the technology that enabled this achievement, his research themes aiming at exploiting all the properties of radio waves, and his thoughts on the importance of researcher well-being for enabling them to make people happy through research.

Rising Researchers

• Junko Takahashi, Distinguished Researcher, NTT Social Informatics Laboratories

  

  Abstract
  The next-generation communication network driven by optical technology will be achieved in the sixth-generation mobile communication system (6G) of the Innovative Optical and Wireless Network (IOWN) era promoted by NTT. However, a problem of concern here is cryptographic technology. For example, even if optical circuits can be achieved, cryptographic operations in their present form would generate delays or excessive power consumption preventing the advantages of optical technology from being fully used. To solve this problem, NTT is researching technology for replacing the complex processing of cryptographic operations traditionally performed by electronic circuits with optical cryptographic operations. In this article, we talk with NTT Distinguished Researcher Junko Takahashi who devised an “optical-operations technique” supporting the IOWN era and implemented “optical cryptographic circuits.” We hear about the present state of research in optical cryptographic technology and the future outlook for this research.

Feature Articles: Recent Updates on Bio-soft Materials Research

• Materials and Sensing Technologies for Constructing On-chip Biological Models

  

  Abstract
  By creating unique process technologies of bio-friendly soft materials, such as hydrogels, and combining them with biomaterials, such as cells, the breadth of research and the potential for application of these technologies have dramatically increased. Under NTT’s Medical and Health Vision, new basic technologies are being developed to contribute to medical care and medicine. This article introduces the latest developments in bio-soft materials research at NTT Basic Research Laboratories.

• Creation of Hydrogel Actuator toward Construction of On-chip Biological Models

  

  Abstract
  To express and maintain organ-like higher-order functions in cultured cells, it is important to create an environment that is close to that of a living organism. NTT Basic Research Laboratories has established a technology to control the shape of hydrogel, a material with properties similar to those of living tissue, on a chip into forming thin-film and tubular architectures that resemble living organs. On the basis of the above-mentioned technology, this article introduces the development of an actuator that can move large, fast, and arbitrary areas by optical stimulation and a technology to control its motion as if it were a living organ.

• Brain-on-a-chip Model Using Deformable Graphene-based Electrode Array

  

  Abstract
  Since the brain transmits electrical signals between neurons in three-dimensional (3D) space, we developed a 3D deformable electrode array to measure electrical signals from a 3D network of cultured neurons using a graphene self-folding technique. By recording the electrical signals spatiotemporally from the electrode array, we demonstrated that the reconstruction of a 3D neuronal network on the electrode array (brain-on-a-chip model) enables us to investigate how neurons communicate with each other and helps us understand how the structure of the neuronal network affects the neuron’s communication.

• Functional Evaluation of Bilayer Lipid for the Development of Artificial Cell-membrane Structures

  

  Abstract
  Lipids and membrane proteins are related in many reactions such as intracellular vesicular transport and intercellular communication. We are studying artificial cell membranes as a bottom-up approach to understand cellular reactions at the molecular level. Various elemental technologies are required to introduce membrane proteins into bilayer lipid membranes, which are the basic structure of cell membranes, and evaluate them. In this article, we introduce our efforts in developing an artificial cell membrane.

• Characterization of Metal Ions in Neurons Using a Superconducting Flux Qubit

  

  Abstract
  In the race to develop superconducting quantum computers, superconducting quantum circuit technology has made remarkable progress. The technology has also been applied to quantum sensing, especially highly sensitive magnetometers. The target of on-chip measurement by superconducting quantum sensors has thus far been limited to impurities in semiconductors. However, the range of applications is not limited to such hard materials. This article describes the detection of ferric ions in neurons with a high-sensitivity, high-spatial-resolution magnetometer using a superconducting flux qubit.

Feature Articles: Urban DTC for Creating Optimized Smart Cities Attentive to the Individual

• Creating Smart Cities through Digital Twins

  

  Abstract
  We describe our initiatives in creating smart cities using digital twin (DT) technology. In these Feature Articles on Urban DTC for Creating Optimized Smart Cities Attentive to the Individual, we first outline the concept of a totally optimized smart city. We then describe a variety of services that use digitalized data and artificial intelligence (AI), an integrated platform that achieves total optimization by interlinking those services, examples of services that link areas over a wide region, and the AI value platform that makes it easy to provide such cross-domain services.

• Urban District Experiences for the Individual Generated by the Linking of Digital Twins—Digital-twin-integrated Platform and Integrated App

  

  Abstract
  An urban district includes a variety of stakeholders each with their own interests with trade-offs existing among those interests. The digital-twin-integrated platform was developed to achieve social well-being by calculating a state that obtains a balance among those trade-offs on the basis of values predicted by multiple digital twins. An integrated app was also developed that provides services for the individual based on pre- and post-behavior context by determining behavior spanning multiple services using a single identifier.

• Personalized Air Conditioning Achieving Both Personal Comfort and Energy Savings

  

  Abstract
  Modern offices use uniform air-conditioning control, which means that office space cannot provide a comfortable environment for everyone since some people will feel cold and others will feel hot. Our aim is to achieve comfortable offices that make it easier for office users to do their work and improve their performance by providing air conditioning at temperatures tailored to personal preferences. In this article, we introduce our work in space control for achieving both energy saving and personal comfort.

• Using Smart-store Behavior Data to Optimize Sales Promotion

  

  Abstract
  Implementation of information and communication technology in retail stores is advancing, with self-scan shops using smart carts and others that enable “empty-handed” purchasing without even going to a register. In such shops, we can obtain point-of-sale data including customer identifiers and behavior data such as movement flows within the store, and that enables us to understand a customer’s behavior leading to a purchase. This was not possible with conventional shops. This article introduces an initiative that uses such data to create a digital twin of a store, which is used for sales promotion or more efficient operations.

• Robot Delivery Service with Mobile Ordering

  

  Abstract
  In urban office districts, there is a movement toward using indoor mobility solutions, such as using robots, to provide necessary services, such as cleaning, security, and delivery, for tenants and building owners to reduce operational costs. Anticipating the use of multiple robots for various services within buildings, efforts are underway to implement systems involving multiple heterogeneous robots. This article discusses efforts toward achieving robot delivery services via mobile ordering, enabling busy office workers to make retail purchases while in the office. It focuses on the development of optimal robot-control technology that accurately predicts robot delivery times and explores optimal travel routes to ensure timely delivery.

• AI Value Platform Accelerates Data Valorization by Consolidating SDSC’s Elemental Technologies

  

  Abstract
  We at NTT Smart Data Science Center (SDSC) are developing an artificial intelligence (AI) value platform to accelerate data valorization by consolidating the results from various industry domains that we have been working on. By cataloging analytical case studies, we aim to support problem design and accelerate valorization by automatically experimenting with processing techniques for aggregated real data, thus shortening the initial trial-and-error phase of data analysis. In this article, we introduce our efforts toward implementing the AI value platform.

• Improving Efficiency of Agricultural-product Distribution by Using a Virtual Market

  

  Abstract
  To improve the efficiency of agricultural-product distribution, NTT is creating a virtual market that can optimize commercial distribution and logistics on a nationwide scale by consolidating information on the supply and demand of agricultural products. This virtual market will help solve the so-called “2024 problem” facing the logistics industry due to the enforcement of new overtime regulations and ease labor shortages in fields related to the distribution of agricultural products, improve the economic effects of distribution by reducing time and costs, and reduce the environmental burden of distribution by reducing greenhouse-gas emissions and food loss.

• Refining Solar-power-generation Plans to Achieve Stable Power Supply by Predicting Total Solar Irradiance

  

  Abstract
  To reduce the environmental burden, it is necessary to adjust the supply and demand of electricity so that the proportion of renewable energy is increased. For solar-power generation, which is widely used, total solar irradiance is the main variable used in power-generation planning because it is strongly correlated with the amount of electricity generated. However, measurement and prediction of total solar irradiance produce values with large errors, leading to large errors in power-generation plans, which in turn cause problems in terms of stable power supply and the cost of adjusting supply and demand. In light of these issues, we developed a technology that combines weather information and power-generation results to predict total solar irradiance with high accuracy in a manner that makes it possible to refine solar-power-generation plans.

Regular Articles

• Sub-surface-hydrogen-measurement Method for Estimating Hydrogen-embrittlement Risk in Concrete Poles

  

  Abstract
  Concrete poles play an important role in the infrastructure providing communication services to customers. If the risk of hydrogen embrittlement of rebar embedded in concrete can be determined from information about the environment in which the equipment is installed, the safety of concrete poles can be further improved. Our research group has developed a method for measuring the sub-surface hydrogen concentration of rebar in concrete poles, which is one of the most important parameters for measuring hydrogen embrittlement.

External Awards

• External Awards