The Kepler triangle, also known as the golden right triangle, is the right triangle with its sides of ratios '1 : φ^1/2 : φ,' where φ denotes the golden ratio. Also known are the silver right triangle and the square-root-three φ right triangle. This study introduces the generalised golden right triangle, which have sides of lengths closely related to φ and the Fibonacci numbers, F_n : '(F_{n - 2})^1/2 : φ^n/2 : (F_n)^1/2φ' for any natural number n. This formalism covers all the known φ-related right triangle, i.e., the Kepler triangle and its kin. As n tends to infinity, the ratios of the sides go to 'φ^-1 : 5^1/4 : φ.' Our model plays an important role in the classroom to study the golden ratio, the Fibonacci numbers and the Pythagorean theorem.

For the first time in 333 years Togai Ito's codex, two maps and a manuscript, is put on a scholar's test bench from Tenri Central Library. This codex derives from the original prepared by the Tokugawa-Shogunate expediters to the Bonin Islands in 1675. Two maps are the nautical chart between Japan proper and the Bonin Islands as well as the coastal chart of the Bonin Islands. The manuscript consists of the log of the ongoing journey, descriptions of island geography and natural history, the list of natural resources brought back to Edo, and the diary of the return journey. Results of the 1675 expedition are revisited at two aspects. One is discoveries of four islands on route (the first historic records). Another is presentation of living birds and bats at Shogun Ietsuna. All discoveries of the endemic are the first historic records. Astonishing is discovery of Purple Swamphen (now extinct).

This paper presents an analytical expression for the closest distance to a finite size facility. The closest distance is the distance from customers to the closest point on a facility, and represents the accessibility of customers to the facility. The distributions of the rectilinear closest distance are derived for rectangular facilities of grid and random configurations. The distributions demonstrate how the density, size, and shape of facilities affect the closest distance. A numerical example shows that if the area taken up by facilities is constant, many small facilities are better than a few large facilities and that rectangular facilities are better than square facilities.

The World Health Organization (WHO) reports that hand hygiene education is important for health workers. However, handwashing methods in hospitals require specialized handwashing knowledge. In this paper, we present a new quantitative handwashing skills assessment method based on the Convolutional Neural Network (CNN). An image capture box with blacklights was created and photos were taken before and after handwashing after the application of fluorescent paint. The photos after handwashing were labeled by specialists in each part. The total number of photos after handwashing labeled by specialists was 585. After that, 9-fold cross-validation was performed on the photos after handwashing to calculate the discrimination accuracy (F-value). As a result, the F-value was 81.26 ± 6.18% in the handwashing image evaluation system using CNN.

This paper presents full modeling of the cross-section of a blue feather barb of Tarsiger cyanurus and computed optical properties of the barb by means of finite element simulations. Cross-sectional models of the blue barbs are created based on SEM and TEM observations and are characterized on the basis of the radial sizes and the arrangements of air-pores. Large-scale finite element method is employed in order to investigate reflective properties of a blue feather barb. Measured and computed results show good agreement in the visible wavelength range, when we take into account optical absorption of keratin.

Although many hypotheses, such as stiffness control and muscle mechano-reflex control, have been proposed for the elucidation of a control system to maintain an upright posture, the detailed mechanism is still unclear. In this study, the characteristics of muscle activity in the upright posture were investigated to verify the stiffness control hypothesis by employing stabilometry and the simultaneous measurement of electromyographs (EMGs). For each experimental test, with the subjects' eyes open/closed during stabilometry, EMGs were recorded for the gastrocnemius muscle, soleus muscle, and tibialis anterior muscles, simultaneously. We discuss a relationship between the center of gravity and muscle activity to control the upright posture. Mathematical models to control the standing posture are also discussed in this study.

The Kepler triangle and its kin are systematically described by the unique formalism (Sugimoto, 2020). The present study affords the super-set of the formalism covering the above-mentioned triangles and other new triangles based on the metallic means and the generalised Fibonacci sequences adjoined to those means. The super-set is given by (the short leg, the long leg, the hypotenuse) = (G_{n - 2}^1/2(m), m^1/2Φ^n/2(m), G_n^1/2(m)Φ(m)), where G_n(m) and Φ(m) designate the nth generalised Fibonacci sequence and the metal mean of the metal number 'm', respectively. The initial members of the golden, silver and bronze right-triangles are presented.

Shizuo Ishiguro, the father of Nobel Prize-winning British novelist Kazuo Ishiguro, studied various sea-level changes, such as seiche, also known as abiki in the Nagasaki dialect, and the 1953 North Sea Flood, with his pioneering use of an analog computer in the 50s and 60s. Note that pioneering studies by Lorenz and Ueda using digital and analog computers were also performed in the 60s. Based on a retrospective review, it is discussed whether nonlinear phenomena, such as chaos, can be observed in line with his pioneering studies. His studies are also reconsidered in the context of advanced education for high-school students.