著者
佐原 宏典 荒井 康雄
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 (ISSN:13446460)
巻号頁・発行日
vol.64, no.3, pp.145-152, 2016 (Released:2016-06-05)
参考文献数
24
被引用文献数
1

This paper proposes a way of quantitative evaluation for a system with design complexity defined by cyclomatic number, coupling, cohesion, scales of system and subsystems, and the number of interface and communication. Though the design complexity would eventually apply to the calculation of reliableness, it essentially enables a comparison between systems. Here, we adopted the design complexity to Japanese microsatellites, and obtained their characteristics and a guideline to improve them. Furthermore, we found a relation between the design complexity and success level of missions accomplished by the microsatellites, i.e. we should have an option to reduce the design complexity in order to increase the success level of a satellite. Thus, the design complexity affects the reliableness in reliability assessment or resource allocation in a project, so that it would establish an applicable reliability assessment specialized for microsatellite, so-called Hodoyoshi Reliability Assessment.
著者
眞庭 知成 花田 俊也 河本 聡美
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 (ISSN:13446460)
巻号頁・発行日
vol.58, no.674, pp.83-89, 2010 (Released:2010-03-25)
参考文献数
18
被引用文献数
3 2

Since the launch of Sputnik, orbital debris population continues to increase due to ongoing space activities, on-orbit explosions, and accidental collisions. In the future, it is expected that a great deal of fragments will be created by explosions and collisions. Thus, the number of space debris may increase exponentially (Kessler Syndrome). This paper analyzes the Kessler Syndrome using the Low Earth Orbital Debris Environmental Evolutionary Model (LEODEEM) developed at Kyushu University with collaboration from JAXA. The purpose of the study aims at understanding the issues related to space environment conservation. The results provide effective conditions of Active Debris Removal which is one of the space debris mitigation procedures.
著者
In-Ho Choi 山下 雅道
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会誌 (ISSN:00214663)
巻号頁・発行日
vol.47, no.551, pp.287-294, 1999-12-05 (Released:2019-04-09)
参考文献数
37
被引用文献数
1
著者
山口 敬之 松岡 健 八桁 純 笠原 次郎
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 = Journal of the Japan Society for Aeronautical and Space Sciences (ISSN:13446460)
巻号頁・発行日
vol.57, no.663, pp.141-147, 2009-04-05
参考文献数
22
被引用文献数
2

In the present study, a dynamics model of an inflow-drive valve for pulse detonation engines (PDEs) is proposed, in which system the inflow of the valve periodically drives the valve piston. Since the inflow-drive valve needs no energy source to drive the piston, the mass flow rate divided by the valve mass is relatively large, and the response time for the mass-flow-rate change can be short. Moreover, the inflow-state condition for the stable valve operation is not restricted. The two-cylinder three-fluid type inflow-drive valve was fabricated. The maximum mass flow rate for one valve was evaluated as 6.3g/s, in which system the mass of the piston, the spring constant, and the supplied pressure were 3.8kg, 9800N, and 1.0MPa, respectively. The total mass flow rate using propellant was evaluated as 12g/s. The PDE system was constructed by using these inflow-drive valves. This system was stably operated in the frequency of 17.52Hz.

3 0 0 0 OA 偶感

著者
砂川 恵
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会誌 (ISSN:00214663)
巻号頁・発行日
vol.50, no.577, pp.21-22, 2002-02-05 (Released:2019-04-12)
参考文献数
3
著者
土肥 直人 馬場 順昭 高野 博行
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 (ISSN:13446460)
巻号頁・発行日
vol.51, no.594, pp.380-387, 2003 (Released:2003-09-26)
参考文献数
10
被引用文献数
1 1

This paper deals with a guidance law for a flight vehicle with varying velocity after thrust cutoff. This guidance law is mechanized by combining the proportional navigation and the pure pursuit navigation with the mixture ratio. Since the performance of the guidance law depends on the ratio, the discussion is focused on the determination of the ratio. Finally, the simulation results show that if the LOS angle noises are small, the proposed guidance law is effective even if the missile velocity decreases and has higher off-boresight ability than the proportional navigation.
著者
山本 悟 葉狩 秀樹 村山 光宏
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 = Journal of the Japan Society for Aeronautical and Space Sciences (ISSN:13446460)
巻号頁・発行日
vol.47, no.540, pp.41-46, 1999-01-05
参考文献数
10
被引用文献数
1

The nonequilibrium condensation generating around the 2-D and 3-D wings in moist air, so-called 'Vapor Trail, ' is numerically investigated. The fundamental equations composed of the compressible Navier-Stokes equations and tho model equations for the phase change based on the classical condensation theory are solved using the fourth-order accurate compact MUSCL TVD scheme and the second-order Runge-Kutta scheme. As numerical examples, the 2-D transonic viscous flows around the RAE 2822 wing in moist air are calculated changing the relative humidity and the calculated results are compared with those in dry air and the experiment. Also the 3-D flows around the ONERA M 6 wing in moist air are preliminary calculated.
著者
林 大介 川崎 繁男
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 (ISSN:13446460)
巻号頁・発行日
vol.67, no.1, pp.9-15, 2019 (Released:2019-02-05)
参考文献数
14
被引用文献数
1 1

The re-entry capsule tracking system is proposed as a shared/dual-use technology with commercial products. This system has portability, and is not affected by the condition of installed equipment in the capsule. In this paper, the detection performance is described about the tracking area assumed from Hayabusa's achievement. By the experiment using the prototype radar, this system was confirmed to be able to detect more than 90% of the area.
著者
飯島 朋子 小林 宙 西沢 啓 山崎 宏二
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会誌 (ISSN:00214663)
巻号頁・発行日
vol.65, no.7, pp.201-207, 2017-07-05 (Released:2017-07-05)
参考文献数
24

宇宙航空研究開発機構(JAXA)では,独自に開発した航空機用電動推進システム技術を飛行実証するため,FEATHER(Flight demonstration of Electric Aircraft Technology for Harmonized Ecological Revolution)と呼称する研究事業を2012年~2015年にかけて実施した.当研究事業を実施するにあたり,国土交通省航空局から電動航空機の試験飛行許可取得が必須であるが,電動航空機の耐空性基準が存在しなかった.そこで航空局との調整の下,電動推進システムを動力滑空機に搭載するためのJAR(Joint Aviation Requirement)-22のガイドライン・CS(Certification Specification)-22の特別要件と現行の耐空性審査項目から,本件が準拠すべき安全性基準の選定と修正を行い,基準への適合性を保証するための推進システム設計及び試験等による各種証明に取り組んだ.本稿では実証試験機や飛行場の選定も含め,各種システムの適合性証明に至るまでの電動航空機の試験飛行許可取得プロセスについて,ノウハウを国内で共有する観点で概説した.