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Abstract  

Patents contain much significant technical information which can serve as an indicator of technological and economical development. This study attempts to forecast the development of the biped robot walking technique in Japan by use of the patent data obtained from the Japan Patent Office. The study applies linear regression to the patent data using three S-curve models developed by Loglet Lab, Pearl, and Gompertz individually. Various parameters inherent to each model including the least sum of modulus error and the least mean of square error of the model are analyzed. The most appropriate model for measuring the inflection point, the growth and the saturation time of the technique is described. Based on the Gompertz model analysis, this study finds that the biped robot walking technique will continue to develop for several decades in Japan and the saturation period is estimated to be around the year 2079–2082. This finding can help related researchers and managers in the robot field to foresee the development trend of the biped robot walking technique in this century.

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Abstract  

The concentration of232Th,230Th and228Th in various human tissues of Japanese subjects obtained at autopsies are reported. The tissue samples were weighed, spiked with234Th tracer and ashed by acid. The solution was dried on a hot-plate. Separation of thorium radionuclides was accomplished through cation-exchange resin chromatography and electrodeposition. The concentrations of thorium isotopes were measured by -spectrometry. Thorium-232 and230Th concentrations were found to be highest in lung, followed by bone. The maximum concentration of228Th was in bone. The lowest concentrations of thorium isotopes were in muscle.

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Abstract  

Instrumental neutron activation analysis (INAA), and inductively coupled plasma mass spectroscopy (ICP-MS) were applied to the determination of major elements and rare earth elements in Japanese Standard Soil Materials (NDG-1 to -8). Eight major elements, Al, Fe, Ti, Ca, Mg, Mn, K, and Na were determined by INAA. A comparison of the data for rare earth elements obtained by INAA and ICP-MS shows that the data of the contents determined by the two different analytical methods are in fairly good agreement with each other.

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Summary  

Due to the rocky neighborhood, consisting of mostly granite with high radium content, an elevated radon concentration was found in a territory of Gifu prefecture situated in the middle of Japan. Radon concentrations in water were measured and were found to be considerably high. Since indoor radon and radon progeny concentrations might be relatively high, their concentrations were also analyzed. Besides the radon and radon progeny, thoron and thoron progeny concentrations were also investigated. Dose estimations for radon and thoron in indoor air are discussed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: K. Tanoi, H. Matsue, H. Iikura, T. Saito, Y. Hayashi, Y. Hamada, H. Nishiyama, N. Kobayashi, and T. Nakanishi

Abstract  

We carried out instrumental neutron activation analysis (INAA) as well as k 0-based prompt gamma-ray analysis (k 0-PGA) to measure the amount of the elements in onions and studied whether the onions collected from different sites can be categorized based on the elemental concentration profile. Six elements (Na, Mg, Cl, K, Ca, Mn) and 3 elements (B, S, Cl) were measured by INAA and PGA in the onions grown in two districts, Hokkaido and Saga, in Japan, respectively. After principal component analysis, it was found that Cl was an important element to feature the producing districts of onions.

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Abstract  

Technological resources are shown to be more concentrated to a few firms than economic wealth. To explain such concentrations, the self-multiplication process with cycle between the innovative and stagnant ages is modeled in terms of the stochastic process. This yields a family of new distributions which is named the ultra-Yule distribution. This new distribution which is quite skew is show to fit the real distributions of patents and of R & D expenditure in the Japanese industry better than the Yule distribution. The properties of this new distribution is discussed.

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Abstract  

The atmospheric concentration of 210Pb and 7Be was observed at Sarufutsu on the coast of the Sea of Okhotsuk in Hokkaido, Japan. Measurements were carried out during the period from February to August, 2001. The atmospheric concentrations of 210Pb and 7Be ranged from 0.2 to 2.5 mBq/m3 and from 0.0 to 4.2 mBq/m3, respectively. The seasonal variation pattern of the atmospheric concentration of 210Pb indicated that the air mass from Chinese Continent reached the coast of the Sea of Okhotsuk.

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Abstract  

The concentrations of 7Be, 210Pb and 210Po of ca. 60 parts of a whole tree of Japanese cedar and of underlying litter and soil samples were determined for studying their transfer in a forest canopy. The results suggest that the mean residence times of 7Be and 210Pb in the forest canopy were ca. 20 and 900 days, respectively, and the dry deposition rate of 7Be on the forest canopy was about a half of the total deposition rate.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Naofumi Akata, H. Kawabata, H. Hasegawa, T. Sato, Y. Chikuchi, K. Kondo, S. Hisamatsu, and J. Inaba

Abstract  

The atmospheric concentrations and deposition fluxes of 7Be and 210Pb were observed biweekly in Rokkasho, Japan on the Pacific Ocean coast at the northern end of Honshu Island, from March 2000 to March 2006, to clarify their regional features. Seasonal variation pattern of atmospheric 7Be concentrations had double peaks, and that of 210Pb had a single peak. Deposition fluxes of 7Be and 210Pb showed the same patterns. The total deposition pattern of 7Be was similar to that commonly seen on the Pacific Ocean side of northern Honshu Island, while the pattern of 210Pb was similar to that commonly seen on the Japan Sea side. The lack of high spine mountains windward in Rokkasho may be the cause of this ambiguity in the winter monsoon season. Total deposition velocities and scavenging ratios of 210Pb were similar to those of 7Be from spring to fall, and showed that both nuclides had a similar removal process from the atmosphere. However, the scavenging ratios of 210Pb were slightly larger than those of 7Be in winter, indicating different behaviors for both nuclides in the scavenging process. The scavenging ratios of both nuclides inversely correlated with precipitation rate, and the ratios in winter were larger than in the other seasons.

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Summary  

Aone year survey of indoor radon and thoron concentrations was carried out in offices and dwellings of the Gunma prefecture, Japan. A passive integrating radon and thoron discriminative monitor was used in the survey. The annual mean radon concentration was 22±14 Bq . m-3, and ranged from 12 to 93 Bq . m-3 among the 56 surveyed rooms. Radon concentration in offices was generally higher than that in the dwellings, with the arithmetic averages of 29 and 17 Bq . m-3, respectively. Radon concentrations were generally lower in the traditional Japanese wooden houses than those houses built with other building materials. Seasonal variation of indoor radon was also observed in this survey. Compared to summer and autumn, radon concentrations were generally higher in spring and winter. The mean value of thoron to radon ratio was estimated to be 1.3, higher values were observed in the dwellings than in the offices. The annual effective dose from the exposure to indoor radon was estimated to be 0.47 mSv after taking the occupancy factors of offices and dwellings into account.

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