２台の送風機並列運転系の数学モデルである３階自律常微分方程式には，ターボ機械特有のサージングに関連して，非周期的アトラクタなどの多様な非線形現象が生じることが知られている．本論文では，近似１次元写像を用いた数値解析により，この系の２パラメータ空間に現れる大域的な分岐現象の調査を行い，超安定曲線及びフィッシュフックの渦巻き構造との関連を明らかにした．特に，フィッシュフックは２重超安定点で連結され，極大値を取る超安定曲線に沿って渦巻く構造を持つことを示し，その上で，主(副)ホモクリニック軌道及び分岐集合を求め，主(副)ホモクリニック分岐集合が周期倍化分岐の極限において存在することを明らかにした．

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The nitration of multiply deactivated aromatic compounds usually requires heating with fum-HNO₃/conc-H₂SO₄ at elevated temperature. However, a combination of NO₂ and O₃ was found to exhibit a powerful nitrating ability toward such deactivated aromatic systems in the presence of MeSO₃H/FeCl₃ as catalyst. Using this reagent system, isophthalonitrile was converted to 5-intro derivative in acetonitrile even at -10 oC and no amide formation was observed under the conditions employed. With moderately deactivated aromatic systems such as tolunitriles and naphthonitriles, nitration can be successfully effected using a NO₂-O₂ system in the presence of zeolite. A remarkable feature of this type of nitration is high and unique regioselectivity. Thus, the nitration of 2-naphthonitrile with the NO₂-O₂ system in acetonitrile at room temperature gave a product in which the 5-nitro/8-nitro isomer ratio was reversed against ordinary nitration based on HNO₃-H₂SO₄ (1.33 versus 0.72).

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In order to develop new chiral spin sources required for elaboration of optically active molecular magnets, we have synthesized five new, optically active phenolic PROXYLs. Since some of the PROXYLs obtained have undergone unexpected racemization in organic solvents such as chloroform, dichloromethane and benzene which have no ability to form hydrogen bonds, we have investigated the mechanism of this racemization. Consequently, it has been clarified that intermolecular hydrogen atom abstraction by NO radial from the phenolic hydroxy group of another molecule is responsible for this racemization, because irradiation of fluorescent light or higher concentration of the PROXYLs in dichloromethane accelerates the racemization whereas the use of hydrogen bond-forming solvents such as THF and EtOH inhibits the racemization. Magnetic susceptibility measurements of chiral crystals of five compounds on a SQUID magnetometer down 2 K have indicated that one optically active compound shows weak intermolecular ferromagnetic interactions at very low temperatures, that another two compounds exhibit antiferromagnetic interactions, and that the rest are paramagnetic.

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In the field of agriculture, crop analysis techniques using satellite imagery have been developed to conduct field survey effectively for grasping agricultural information, such as crop acreage, yield and grain quality. However, in case that the estimation model is constructed based on the field data, abnormal field data should be excluded to prevent adverse effects. The abnormal fields are extracted based on Mahalanobis’ distance and NDVI of fields calculated using SPOT satellite imagery. We conducted a field survey in Hokkaido to accumulate knowledge about the condition of the extracted fields on the ground. The extracted fields included undamaged fields including ‘growth delay’ and ‘no growth delay’ and damaged fields including ‘rice blast’, ‘sediment inflow’, ‘cool weather’, ‘flooded’, and ‘lodging’. Experimental results show that Mahalanobis’ distance is more suitable for detecting these field than NDVI.

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Leaf Area Index (LAI) is one of the most important indices for monitoring crop growth, but obtaining field measurements is laborious and time-consuming. In recent years as unmanned aerial vehicles (UAVs) have become a popular tool, it has been expected that estimation methods of LAI will be developed for UAV multispectral monitoring. However, our previous study suggested that solar radiation conditions distinctly affect observed values of canopy reflectance and vegetation indices. In this study, we examine several LAI estimation methods based on field measurement data for UAV multispectral monitoring under various solar radiation conditions. Eight paddy fields located in Sendai, Miyagi Prefecture, were selected for the field measurement of LAI and UAV multispectral monitoring. Compared with the LAI estimation based on non-linear regression using the enhanced vegetation index 2 (EVI2) as an explanatory variable, that based on multiple regression using EVI2, background reflectance and solar radiation conditions as explanatory variables improved root mean square error (RMSE) from 0.532 to 0.496 at LAI under 3.5, while it made RMSE worse from 0.929 to 1.120 at LAI over 3.5. This result suggests that the improvement of estimation accuracy by including solar radiation conditions is not consistent, probably due to the uneven data for the conditions. The LAI estimation based on support vector regression using the training data simulated by a radiative transfer model improved RMSE to 0.458 at LAI over 3.5. This implies that even data for the conditions provided by the radiative transfer model simulation properly trains the support vector regression, and improves the accuracy and robustness for LAI estimation.

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目的　近年ベトナムは目覚ましい経済成長を遂げ，人々のライフスタイルが変化してきたことに伴い非感染性疾患（NCDs：Non-Communicable Disease）患者が増加している。ベトナムにおけるNCDs対策の現状と課題を明らかにし，ベトナムと日本のNCDs対策について検討する。

方法　平成27年度地域保健総合推進事業（国際協力事業）として，11人の公衆衛生医師から成る調査団は平成28年1月11日～15日の日程でベトナムの首都ハノイと近郊を訪れ，WHO現地オフィス，ベトナム保健省をはじめ現地の保健医療機関を訪問し，ベトナムにおけるNCDs対策について調査を行い，意見交換を行った。

結果　2014年のデータによると，ベトナムでは全年齢層の死亡原因のうちNCDsが73%を占めており，近年急激にNCDs患者が増加している。その主な行動リスクファクターは，食事，喫煙，飲酒，運動不足，である。NCDs対策を行う上での問題点として，国民のNCDsに対する認知度の低さ，地域格差のある医療，専門的な知識を持った保健医療スタッフの不足，NCDsサーベイランスが行われているものの実態を反映できていない，などが挙げられる。

　ベトナムでは2002年に国家運営委員会を立ち上げNCDsプログラムを策定し，各疾患に対するスクリーニング方法や治療ガイドラインが作成されたが3次予防にとどまり，1次予防，2次予防対策が十分ではなかった。現在，WHOの技術的支援を受けながら，NCDsのリスクファクターを減らす取り組みなど予防に重点を置いた対策が始まったばかりである。

結論　今後，ベトナムのNCDs予防対策が国民1人1人に行き届くことが求められており，日本の健康日本21のような国民運動，特定健診など全国規模のスクリーニング事業など参考になると思われた。また，日本における地域住民の自主的な地区組織による地域保健活動および保健師による地域への訪問活動と保健指導が地域の保健向上に大きく貢献した経験は，ベトナム国でも応用できると思われた。さらに人材不足などの課題は日本でも共通しており，幅広く健康課題に取り組む保健医療スタッフの確保と能力の強化が求められる。

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The soil moisture mapping was attempted by analysing observation data from several artificial satellites. Until now, only a few studies attemted a wide area mapping using satellite data. Clearly, the estimation of soil moisture in a wide area is important from a view point of water resources management. Therefore, we used the volumetric soil moisture as a criterion variable of the statistical estimation. The measurements of the volumetric soil moisture were carried out at the time synchronized with the satellite visit time. We used the backscattering coefficient of SAR data, the inclination of ground, the roughness of ground surface and the vegitation index as the predictor variables. These variables were caluculated on the basis of the geographical information of Digital National Land Information and multiple satellite data. Soil moisture mapping was conducted by using the results of multiple regression analysis between the mesurement of soil moisture and satellite data.

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The estimation of crop phenology is necessary to grasp the water use of irrigated farmlands. To estimate the crop phenology, time-series patterns of Leaf Area Index (LAI) are considered effective. A method is proposed for extracting LAI time-series patterns by calculating the difference between vegetation coverage estimated in visible bands and visible + near-infrared bands. The method proved to be more suitable for the estimation of LAI time-series patterns than conventional vegetation indices.

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This essay concerns the activity of the Nisei amateur orchestras in Hawai'i after the Pacific War.
In the postwar period, there were more than 40 Nisei orchestras performing Japanese popular songs at events and parties held by and for Americans of Japanese ancestry in Hawaii. Some of the orchestras also put on stage shows and produced many records. Of the few pieces composed by Nisei musicians, “Wakare no Iso Chidori, ” composed by Francis Zanami, became a big hit in Hawaii. A few years after it's release in Hawaii, a famous Japanese singer, OMI Toshiro, also recorded this song and his version became quite popular in Japan. Over the same period, several Nisei singers made their debuts in Japan as well.
The Nisei Orchestras flourished only for four or five years after the war. In that short period, they used music as a tool to express their confidence and pride as Americans of Japanese ancestry, as well as to reestablish ties with the land of their parents.

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