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Seventh Aerodynamics Prediction Challenge (APC-7) ワークショップ (2021年6月30日. オンライン開催), Seventh Aerodynamics Prediction Challenge workshop (APC-7) (June 30, 2021. Online meeting), 注記: 第53回流体力学講演会/第39回航空宇宙数値シミュレーション技術シンポジウム(ANSS)オンライン内で開催, 形態: カラー図版あり, Note: Workshop was held in The 53rd Fluid Dynamics Conference / The 39th Aerospace Numerical Simulation Symposium Online, Physical characteristics: Original contains color illustrations, 資料番号: AA2130007009, レポート番号: JAXA-SP-21-002

Sixth Aerodynamics Prediction Challenge (APC-6) ワークショップ (2020年9月28日. オンライン開催), Sixth Aerodynamics Prediction Challenge workshop (APC-6) (September 28, 2020. Online meeting), 注記: 流体力学講演会/航空宇宙数値シミュレーション技術シンポジウム2020オンライン内で実施, 形態: カラー図版あり, Note: Workshop was held in Fluid Dynamics Conference / Aerospace Numerical Simulation Symposium 2020 Online, Physical characteristics: Original contains color illustrations, 資料番号: AA2030015008, レポート番号: JAXA-SP-20-005

Fifth Aerodynamics Prediction Challenge (APC-V) ワークショップ (2019年7月1日. 早稲田大学早稲田キャンパス国際会議場), 新宿区, 東京, Fifth Aerodynamics Prediction Challenge workshop (APC-V) (July 1, 2019. International Conference Center, Waseda University), Shinjuku-ku, Tokyo, Japan, 注記: 第51回流体力学講演会/第37回航空宇宙数値シミュレーション技術シンポジウム内で実施, 形態: カラー図版あり, Note: Workshop was held in 51st Fluid Dynamics Conference / 37th Aerospace Numerical Simulation Symposium, Physical characteristics: Original contains color illustrations, 資料番号: AA1930013010, レポート番号: JAXA-SP-19-008

Evaluating the magnitude of natural climate variations is important because it can greatly affect future climate policies. As an example, we examine the influence of changes in solar activity (solar wind in particular) on surface temperatures (Ts) and major teleconnection patterns such as the Arctic Oscillation and Pacific Decadal Oscillation. We compared correlation maps (spatial distribution of correlation coefficient) for a combination of Ts and a geomagnetic index (aa, an indicator of solar wind strength) and a combination of Ts and the teleconnection patterns. The phase of the quasi-biennial oscillation of the equatorial zonal wind and magnitude of sunspot number were considered. As a result, we found that the influence of the solar wind is as strong as that of the teleconnection patterns and hence, the former appears to affect the climate via the latter. It was also found that both the solar wind and ultraviolet change should be considered to explain the influence of solar activity variability, i.e., a multi-pathway scheme is necessary., 22 pages including 12 figures and two tables

The existence of a worldwide trend that the world's manufacturing site is moving toEast Asia is well known. Very large part of the products produced in these districts are to betransported to the U.S.A. and are concentrated to rather small number of ports, including airports.These situations are causing very serious traffic problems. New products are required to betransported swiftly by air. Once the market demands are stable, the products should be sent ratherslowly but in larger amount. Since the airport of China is quite restricted, transportation cost isincreasing and also the time for transportation is increasing. Here, the third method is appearing.This is the so-called Sea-and-Air transportation. Its cost and time in transit takes a mean positionbetween Air and Ocean freight services. However, there have been existing no reasonable strategyhow to allocate these three methods for the transportation. In the previous paper the optimalcondition was considered under the assumptions that products are transported directly after theirproduction. Here, the same problem is considered under the assumption that all products arealready produced and stored in the inventory. Products are transported following the demands fromthe consuming districts. The most efficient transportation for such case is considered with the helpof simulations.

This article reviewed recent progresses in the design of a new class of chemical oscillators and developed a generic model that could qualitatively reproduce those photochemical oscillations seen in experiments. The two oscillators discussed in this report are based on the photolysis of 1,4-benzoquinone and its derivatives, in which external illumination is vital in initiating and sustaining the reaction processes. Nonlinear behavior in these two photocontrolled chemical oscillators are analyzed as a function of light intensity and the initial concentration of reagents including 1,4-benzoquinone, 1,4-hydroquinone, 2-methyl-1,4-benzoquinone, bromate, and sulfuric acid. A generic model proposed initially for the uncatalyzed bromate-aromatic compound reactions was modified here to account for the photolysis of 1,4-benzoquinone or 2-methyl-1,4-benzoquinone. The modified model qualitatively reproduced chemical oscillations and their dependence on light intensity.

There is a trend toward that world's manufacturing sites are moving to East Asia. After the production, these products are transported to the adavanced nations for their consumption demands. Among such advanced nations, U.S.A. has the largest demand and then Japan and other European countries follow. It should be noted that these Asian districts used for the production sites are rather restricted. Therefore, the volume of products transported from these restricted districts of Asia to U.S.A. is becoming tremendously large. This situation is causing very serious taraffic problems. The new products are required to be transported swiftly by air. Once the consumption and market demands are stable, the products should be sent rather slowly but in larger amount. However, the airports of China are quite restricted and while the amount of transportation is becoming large. As a result, transportation cost is increasing and also the time for transportation is increasing. Here, the third method is appearing. This is the so-called Sea and Air transportation. The cost and time in transit take mean positions between Air and Ocean fleight servises. There ecists no reasonable strategy how allocate these three methods for the taransportation. This paper is an attempt to theoretically describe this mechanism and to find out the optimal result.

複数衛星による編隊飛行において、各衛星が自身の位置情報を必ずしも既知として扱えない場合、情報伝達構造がシステム安定化に重要な役割を果たすと考えられる。また実用上、信号雑音や時間遅れに対してロバスト安定となる情報伝達構造を明らかにすることが必要である。相対的な信号の経路を決める問題は、システム行列の要素配置を決める問題に帰着できると考えられるため、本発表では、システム行列に含まれる不確定要素や時間遅れがどのような要素配置を許容できるか示すことを目的とする。つまり、線形不確定時間遅れシステムが、任意の大きさの不確定変数と時間遅れに対してロバスト安定化可能となるためのシステム行列の幾何学的条件を導出する。, In the case when each spacecraft does not necessarily know its absolute position for formation flight control, the structure of information flow plays an important role for the stabilizability of the overall system. Taking account of practicality, the information propagation structure that can robustly stabilize the system against signal noises and time delays needs to be developed. The problem of designing the relative path of information flow is reduced to the problem of allocating the nonzero element to the system matrices. The objective in this paper is to derive the conditions for the system to be robustly stabilizable against time-varying uncertain parameters and time-varying delays, whose values are unknown but bounded in arbitrarily large compact sets. It is shown that the conditions obtained here have a particular geometric configuration., 資料番号: AA0063481003

Above-ground biomass was allometrically estimated to quantify the amount of mangrove species in selected quadrats of Xuan Thuy National Park. Physicochemical properties of surrounding waters and soils were measured and treated stochastically by correlational analysis with estimated biomass values. Correlation results suggested that qualities of surrounding waters and soils are not the principal inhibitors of mangrove growth in Xuan Thuy. The available historical records infer that the main factor of mangrove loss in the past lay on land reclamation for shrimp aquaculture. In addition, results of correlation analysis showed geographical coincidence of mangrove fragmentation with influence area of water channeling used for aquaculture activities. Furthermore, the distribution of anomalous values of metals concentration was corresponding with anthropological activities associated to clam aquaculture and sand extraction. Based on the aforementioned analysis and the information on anthropological activities in the buffer zone of Xuan Thuy, were provided basic information on inherent environmental stressors of ecosystems in Xuan Thuy National Park. Sinh khối trên mặt đất đã được ước tính theo phương pháp tương quan sinh trưởng để đưa ra số lượng các loài đước trong các mẫu vuông được lựa chọn tại Vườn quốc gia Xuân Thủy. Các đặc tính hóa-lí của những vùng nước và đất xung quanh đã được đo đạc và xử lí ngẫu nhiên bằng cách phân tích tương quan với những giá trị sinh khối ước tính. Kết quả tương quan cho thấy rằng chất lượng nước và đất xung quanh không phải là những thước đo chính cho tốc độ phát triển cây đước ở Xuân Thủy. Những ghi chép cũ đã kết luận rằng việc sử dụng đất để nuôi tôm là tác nhân chính dẫn tới suy giảm loài đước trong quá khứ. Bên cạnh đó, kết quả phân tích tương quan cho thấy sựtrùng hợp về mặt địa lý giữa sự phân mảnh của loài đước và những vùng nước bị ảnh hưởng do việc nuôi trồng thủy sản. Hơn nữa, sự phân bố bất thường của các giá trị đo mức độ tập trung kim loại cũng tương ứng với các hoạt động nuôi trồng thủy sản và khai thác cát của con người. Những phân tích nêu trên và nghiên cứu về hoạt động của con người tại vùng đệm của Xuân Thủy sẽ cung cấp những thông tin cơ bản về những mối đe dọa môi trường hệ sinh thái tại Vườn Quốc Gia Xuân Thủy.

Above-ground biomass was allometrically estimated to quantify the amount of mangrove species in selected quadrats of Xuan Thuy National Park. Physicochemical properties of surrounding waters and soils were measured and treated stochastically by correlational analysis with estimated biomass values. Correlation results suggested that qualities of surrounding waters and soils are not the principal inhibitors of mangrove growth in Xuan Thuy. The available historical records infer that the main factor of mangrove loss in the past lay on land reclamation for shrimp aquaculture. In addition, results of correlation analysis showed geographical coincidence of mangrove fragmentation with influence area of water channeling used for aquaculture activities. Furthermore, the distribution of anomalous values of metals concentration was corresponding with anthropological activities associated to clam aquaculture and sand extraction. Based on the aforementioned analysis and the information on anthropological activities in the buffer zone of Xuan Thuy, were provided basic information on inherent environmental stressors of ecosystems in Xuan Thuy National Park. Sinh khối trên mặt đất đã được ước tính theo phương pháp tương quan sinh trưởng để đưa ra số lượng các loài đước trong các mẫu vuông được lựa chọn tại Vườn quốc gia Xuân Thủy. Các đặc tính hóa-lí của những vùng nước và đất xung quanh đã được đo đạc và xử lí ngẫu nhiên bằng cách phân tích tương quan với những giá trị sinh khối ước tính. Kết quả tương quan cho thấy rằng chất lượng nước và đất xung quanh không phải là những thước đo chính cho tốc độ phát triển cây đước ở Xuân Thủy. Những ghi chép cũ đã kết luận rằng việc sử dụng đất để nuôi tôm là tác nhân chính dẫn tới suy giảm loài đước trong quá khứ. Bên cạnh đó, kết quả phân tích tương quan cho thấy sự trùng hợp về mặt địa lý giữa sự phân mảnh của loài đước và những vùng nước bị ảnh hưởng do việc nuôi trồng thủy sản. Hơn nữa, sự phân bố bất thường của các giá trị đo mức độ tập trung kim loại cũng tương ứng với các hoạt động nuôi trồng thủy sản và khai thác cát của con người. Những phân tích nêu trên và nghiên cứu về hoạt động của con người tại vùng đệm của Xuân Thủy sẽ cung cấp những thông tin cơ bản về những mối đe dọa môi trường hệ sinh thái tại Vườn Quốc Gia Xuân Thủy., Journal of Vietnamese Environment, Vol 5 No 1 (2014)

JSTさきがけ研究集会 環境問題における数理の可能性. 平成20年6月11日～平成20年6月13日. 札幌市, It is said that algicidal bacteria can be used as biological control agents for algal blooms. We examined influences of algicidal bacteria on microbial communities in a laboratory experiment as a first step of ecological risk assessment. A microcosm, which consists of wild protozoa, bacterioplankton, and cultured Microcystis aeruginosa NIES 99, was constructed as a model microbial ecosystem of eutrophic lakes with algal blooms. Lysobacter enzymogenes subsp. enzymogenes AL-1 (DSM 1895) was added to the microcosm as an algicidal bacterium. Ciliates, flagellates, fungi, and M. aeruginosa NIES 99 were observed in control runs. In the runs with L. enzymogenes AL-1, although M. aeruginosa NIES 99 was not lysed, the other microbes disappeared. We address that applications of algicidal bacteria to actual lakes are considered to be ecologically risky contrary to the previous ideas.