Ultra-Lightweight Deployable Antenna Membrane Technology for Future Non-terrestrial 6G Network and Earth Observation

A deployable antenna membrane is one of the promising solutions to achieve a higher speed of satellite communication and earth observation in small satellites. Unlike conventional deployable antennas, the proposed approach permits low flatness of the antenna membrane and compensates it electrically. By eliminating the conventional large deployment and support structure, the proposed non-planar membrane can be lighter and installed in small satellites. We introduce two types of membrane antennas: reflectarray antennas and active phased-array transceivers

Lead-free piezoceramics - Where to move on?

Lead-free piezoceramics aiming at replacing the market-dominant lead-based ones have been extensively searched for more than a decade worldwide. Some noteworthy outcomes such as the advent of commercial products for certain applications have been reported, but the goal, i.e., the invention of a lead-free piezocermic, the performance of which is equivalent or even superior to that of PZT-based piezoceramics, does not seem to be fulfilled yet. Nevertheless, the academic effort already seems to be culminated, waiting for a guideline to a future research direction. We believe that a driving force for a restoration of this research field needs to be found elsewhere, for example, intimate collaborations with related industries. For this to be effectively realized, it would be helpful for academic side to understand the interests and demands of the industry side as well as to provide the industry with new scientific insights that would eventually lead to new applications. Therefore, this review covers some of the issues that are to be studied further and deeper, so-to-speak, lessons from the history of piezoceramics, and some technical issues that could be useful in better understanding the industry demands. As well, the efforts made in the industry side will be briefly introduced for the academic people to catch up with the recent trends and to be guided for setting up their future research direction effectively.ope

Space Demonstration of Two-Layer Pop-Up Origami Deployable Membrane Reflectarray Antenna by 3U CubeSat OrigamiSat-2

3U CubeSat OrigamiSat-2 demonstrates a 50-cm × 50-cm two-layer pop-up Origami deployable membrane reflectarray antenna in space. The membrane has small stowage volume and high gain even though it has low flatness because of a large enough antenna area to cover its un-flatness. C-band transmitter is equipped in the CubeSat and offers 20-Mbps amateur satellite communication. In 3U size, a 1-m length deployable gravity gradient mast and magnetic torquer are equipped to stabilize and control its attitude. A camera is attached to the satellite to measure the shape of the membrane antenna. OrigamiSat-2 was selected as the Innovative Satellite Technology Demonstration-4 by Japan Aerospace Exploration Agency (JAXA) and is going to be launched in 2024 by Epsilon Launch Vehicle

Development of a Multifunctional Lightweight Membrane with a High Specific Power Generation Capacity

As a lighter power generation system, Japan Aerospace Exploration Agency (JAXA) and Sakase Adtech Corp. are developing a demonstrator component named “Harvesting Energy with Lightweight Integrated Origami Structure” (HELIOS), which is a deployable lightweight membrane structure. HELIOS has solar arrays on its surface and demonstrates the technology which enables higher specific power generation capacity compared to the conventional solar array panels. The membrane also has communication antennas, showing the potency of lightweight membrane’s multifunctionality such as large data transmitting by 5G antennas and high-resolution observation by interferometer antennas. This paper presents the component’s concept and design, and the expected achievements

Monocular Underwater Stereo – 3D Measurement Using Difference of Appearance Depending on Optical Paths –

Abstract — Sensing in aquatic environments meets the difficulty that, when a camera is set in air behind a watertight glass plate, image distortion occurs by refraction of light at the boundary surface between air and water. This paper proposes an aquatic sensing method to execute three dimensional measurement of objects in water by taking refraction of light into account. The proposed method is based on a monocular stereo technique using a difference of appearance depending on optical paths. Optimization of the angles of refracting surfaces which are key elements of the sensing device is given to realize the accurate measurement. Experimental results show the effectiveness of the proposed method. I

Computerized Tomography of Two Patients with Morning Glory Syndrome

Morning glory syndrome (MGS), an uncommon optic disc anomaly, is characterized by a funnel-shaped, excavated optic disc surrounded by chorioretinal pigmentary disturbance. Generally, it is an isolated ocular abnormality. The authors describe two patients in whom MGS developed in association with brain abnormalities. In both cases, there was enlargement of the optic nerve that showed increased radiodensity similar to that of sclera and cavum vergae in the brain cavity present in computerized tomography (CT). To our knowledge, the coexistence of MGS, cavum vergae and an enlarged retrobulbar optic nerve showing increased radiodensity have not been previously reported. The findings suggest that MGS may be based on a developmental anomaly involving the brain, and the enlarged optic nerve may be associated with sclera because of the isodensity in CT

Universal newborn hearing screening: knowledge of pediatricians and neonatologists in the city of Jundiaí, São Paulo, Brazil

INTRODUCTION: Hearing loss has severe emotional, psychological, and social consequences. The early identification of hearing impairment is crucial. OBJECTIVE: To evaluate and quantify the knowledge of neonatologists, pediatricians, and residents in pediatrics regarding detection, risk factors, early diagnosis, and referral for rehabilitation of patients with neonatal hearing loss in Jundiaí, state of São Paulo, Brazil. METHODS: This was a cross-sectional contemporary cohort study including 47 physicians from three hospitals, including a questionnaire with 15 items. RESULTS: Most respondents (83%) had received information about hearing loss in their medical courses, but most had no knowledge of techniques for hearing evaluation, and degrees and types of loss. All physicians agreed that in the first six months of life, it is possible to evaluate hearing function and that it is the physician's responsibility to assess the newborn. Regarding the age that the child can receive auditory rehabilitation, the end of the first year and the second year of life predominate. CONCLUSION: Most respondents know the risk factors for the detection of neonatal hearing impairment, know how to perform procedures, and recognize the importance of diagnosis of hearing loss and the need to refer suspected cases, but most do not know the techniques used to assess hearing in newborns