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Identifying the insufficient requirements, such as missing or lacking requirements, is important to prevent serious accidents for CPSs (Cyber-Physical Systems), such as launch vehicles and spacecrafts which often required to be self-adaptive. In JAXA (Japan Aerospace Exploration Agency), several review boards in place to verify the requirements toward space systems from various viewpoints which often derived from the reviewer's experience about anomalies. However, the impossibility of assigning a well-experienced reviewer to all review opportunities highlights the importance of sharing their viewpoints. In this paper, we aimed to extract and exploit associations between development documents and archived anomaly reports about space systems, thereby identifying the lacking requirement in the review. An association between these two documents can be treated as a viewpoint of the review, which contributes to preventing previously experienced anomalies. To cope with this problem, we propose a CNN (Convolutional Neural Network) model that predicts the correlation of documents. A collection of judgments about meaningfully related pairs of text was prepared to train the proposed model to contribute to detect the lack of requirements. Experimental results have shown that the performance of the proposed method is significantly better than that of baseline methods (i.e., 71.0% in F-measure). Also, further investigation has shown that not only the word similarity, but different attributes are necessary to solve our problem.

System-level Software Failure Mode and Effects Analysis, called as FMEA, that is highly focused on software behavior (here in after SS-FMEA) is difficult to identify effective failure modes which may lead to a serious accident due to the systemic nature of failures rather than random hardware failures. The study has modeled insights derived from the best practices of space system’s SS-FMEA and proposed a framework to assist the novice engineer in identifying high impact failure modes.

We provide an operational scenario-based assurance method for assuring the safety of a software product. Software safety is usually demonstrated by assessing the software development process in what is called a process-based approach. Because the process-based approach indirectly explains safety of software product, it cannot explicate safety boundary: Software product is safe or unsafe in what context of use. In this paper, we focus on operational scenario and unusual events which can occur in the scenario. The proposed method provides an operational scenario-based safety case which explains tolerable and not-tolerable abnormal scenarios including unusual events as the boundary. The method promotes domain experts identifying unusual events from a normal scenario. Furthermore, it constructs scenario-based safety case by using Event Sequence Diagram. To evaluate the method, we applied it to a ground system for artificial satellite, and engine control system of the rocket system. As a result, we conclude that the method can construct a valid operational scenario-based safety case.

形態: カラー図版あり, Physical characteristics: Original contains color illustrations, Accepted: 2017-11-16, 資料番号: PA1810055000

Failure Modes and Effects Analysis (FMEA) for software-intensive systems (called software FMEA in this paper) requires the ingenuity of engineers to set failure modes because software itself never fails as hardware does with physical phenomena. Successful software FMEA allows the experience, knowledge, identification of appropriate items and guide words to be integrated in the engineer's mind. Therefore, software FMEA could be considered a somewhat imaginative activity that largely depends on the engineer's competence. In the space domain, there tends to be less experience on software FMEA as compared to other domains having a shorter development cycle. In addition, the limited concrete knowledge about an unknown system and its environment under operation tends to limit the ideas for analysis when a single engineer performs software FMEA. As a result, we sometimes experienced software FMEA activity that had a negligible effect on the subsequent development phase. To resolve this issue, analysis and review by several engineers are adopted as a solution to cover the lack of experience and competence by an individual. Team reviews are generally useful to expand the idea to lead failure modes. However, a team review may offer a biased result when applying an ad hoc method such as brainstorming. To avoid a biased result, revealing the thinking process and discussion points can help guide proper discussion and also add various ideas from several engineers. Therefore, we proposed a novel method of visualizing the thinking process that led to failure modes by extending Goal Structuring Notation (GSN). Team members will be expected to stimulate ideas by looking at artifacts that visualized the scope of failure mode. Any missing item or possible failure mode can thus be discussed, allowing team members to easily add ideas for the analysis. The team review with the proposed method successfully identified meaningful failure modes in a development project at the Japan Aerospace Exploration Agency (JAXA). Moreover, failure mode and its end effects analysis led by the proposed method contributed not only to software design but also to software testing for setting test cases of adverse conditions.

Earth-observation satellites carrying synthetic aperture radar instruments have stringent requirements on control of Earth-referenced repeat-track orbits. This precision control leads to frequent orbital maneuvers, thus burdening daily ground operations. To achieve high accuracy with minimal ground-based workload, we propose a novel autonomous orbit control method that allows both in-plane and out-of-plane maneuvers to be planned and performed autonomously. Furthermore, a maneuver slot concept is proposed to prevent conflicts with payload data-take opportunities. The proposed method has been implemented on the Advanced Land Observing Satellite-2 and has been in practical use since August 2014. This is the first attempt to apply autonomous precision orbit control within a tube-shaped control window for regular operation of an Earth-observation satellite. Details of the proposed method and Advanced Land Observing Satellite-2 flight results are presented in this paper, and experiences and lessons learned from the operation are discussed., 形態: 図版あり, Physical characteristics: Original contains illustrations, 資料番号: PA1610093000

To identify a molecule involved in sperm-egg plasma membrane binding at fertilization, a monoclonal antibody against a sperm-surface glycoprotein (SGP) was obtained by immunizing mice with a sperm membrane fraction of the frog, Xenopus laevis, followed by screening of the culture supernatants based on their inhibitory activity against fertilization. The fertilization of both jellied and denuded eggs was effectively inhibited by pretreatment of sperm with intact anti-SGP antibody as well as its Fab fragment, indicating that the antibody recognizes a molecule on the sperm's surface that is necessary for fertilization. On Western blots, the anti-SGP antibody recognized large molecules, with molecular masses of 65-150 kDa and minor smaller molecules with masses of 20-28 kDa in the sperm membrane vesicles. SGP was distributed over nearly the entire surface of the sperm, probably as an integral membrane protein in close association with microfilaments. More membrane vesicles containing SGP bound to the surface were found in the animal hemisphere compared with the vegetal hemisphere in unfertilized eggs, but the vesicle-binding was not observed in fertilized eggs. These results indicate that SGP mediates sperm-egg membrane binding and is responsible for the establishment of fertilization in Xenopus.

地下構造物を構築する際，鋼管で荷重を受け持たせ，鋼管間の止水を凍土で行うことが考えられる．本研究では，止水を保つために最も必要な凍土と鋼管との凍着維持条件を調べた．2本の鋼管と凍土とを組み合わせたはりの短期曲げ実験を行い，凍着破壊荷重と凍土温度および土質との関係を調べた．その結果，それらの影響は少なく，高温かつ薄い凍土でも凍着維持が可能であることを示した．また，工期の長い現場で凍土が長期間曝された状態を想定した定荷重下での曲げクリープ実験も行い，鋼管との凍着が維持できれば，凍土のクリープ変形は抑制されて破壊には至らないことを明らかにした．最後に，現場モデルの応力解析に基づいて，掘削中の鋼管露出は極力少なくするべきであることを示し，鋼管埋設精度や支保間隔の管理に関する留意点を提示した．

The acrosome reaction of Xenopus sperm is triggered by the acrosome reaction-inducing substance in Xenopus (ARISX), an oviductal pars recta-derived, sugar-rich substance decorated on the entire surface of the vitelline envelope (VE) during ovulation. Here we addressed the functional importance of the sugar moiety in ARISX. Among various lectins examined, soybean agglutinin and Dolichos biflorus agglutinin were shown to abolish the acrosome reaction-inducing activity of ARISX present in pars recta extract or on the VE, indicating the importance of the terminal α-N-acetylgalactosamine residue for the function of ARISX. Consistently, the acrosome reaction-inducing activity was not affected by proteinase K digestion, in spite of the simultaneous shift of ARISX to a smaller molecular weight. Indirect immunofluorescence microscopic examinations showed that ARISX was distributed as two types of structures on VE; thick fiber-like materials and thin filamentous materials, and that a new structure appeared on the fertilization envelope instead of the thin filamentous materials. Sperm from several amphibian species were subjected to an in vitro assay during induction of the acrosome reaction with ARISX. The resulting limited population of sperm from a non-Xenopus species underwent acrosome reaction, implying a weak species-specificity of ARISX.

application/pdf, テクニカルレポート, 本研究では,短期化が進むソフトウェア開発サイクルに対応するために,アジャイル開発において全側面の仕様を同時に少しずつ設計することに焦点を当てて議論する.現在のソフトウェア開発では,UML設計とGUI設計はほぼ同じ工程で行われるにもかかわらず,最初からUML設計にGUI設計を取り入れた設計支援ツールは見当たらない.これではアジャイル開発において,細かい繰り返しによる修正が円滑に行われず,利点である開発期間の短縮という効果が失われてしまう,本研究では,MVCモデルパラダイムに基づき,UML設計でModelを,UI設計でViewを,UML設計とUI設計の関連付けによって Controllerを記述可能にすることで,UML設計とUI設計を同時に支援するツールの開発を試みた., In this study, it is discussed to design the specification concurrently on all points of view in the agile development. The UML modeling and the UI design are done in the same process for the design of software development. Nevertheless, there is no design support tool which adopted UI design for the UML modeling. Therefore, in agile development, the effect of shortening at the development period is lost. This study describes the follows. In the base of MVC model paradigm, the model part and the view part is described by UML modeling and UI design respectively. And the controller part is described by relating the UML modeling and the UI design.

鋼管など他部材との合成体凍土の構造解析への適用をねらいとして，圧縮および曲げ実験から砂および粘土凍土の変形係数を調べた．まず，圧縮変位から求める変形係数は供試体端部の乱れの影響を受けて過小評価であることを示し，この影響を排除する方法を提案した．また，圧縮および曲げ実験について，変形係数に影響を及ぼさない供試体寸法の範囲を示した．続いて，幾つかの影響因子を変化させた実験から,ひずみ速度および乾燥密度が変形係数に及ぼす影響は小さく，圧縮と曲げとの変形係数の差も少ないことを示し，変形係数を温度との関係式で表すことを提案した．最後に，合成体凍土の破壊や凍着切れを扱う弾塑性解析用に，応力－ひずみ曲線のバイリニアモデル化に基づいて，凍土の構成式を提示した．

地盤凍結工法において,円形構造物に接する凍土を造成する場合,凍着せん断応力の発生方向や大きさは凍着曲面上の位置によって異なる.そのため,凍着せん断方向を1方向のみとする従来の凍着試験だけでは凍着曲面の安全性を定量的に評価することができない.今回,砂凍土と鋼管とを用いた曲面凍着せん断実験を行った.凍着破壊は,凍土の凍着位置や厚みによって,凍着面全域に生じる場合,凍着面の一部だけ生じる場合,全く生じず凍土部のみ破壊する場合があった.そこで,凍着面でのせん断応力の解析に基づく凍着破壊発生の判定式を導いた.この判定に基づく破壊荷重や凍着破壊の範囲および破壊モードの解析結果が実験結果に一致することから,判定の妥当性を確認した.

凍結工法を行う際の凍結膨張による構造物変位への対策工を，現行よりも合理的に行うためには，地盤変形予測の精度向上が不可欠である．本研究では，予測精度向上のために，三軸凍上実験式に基づく土の凍結線膨張率を取り込んだ地盤変形解析法を提案した．凍結領域内における熱流方向の異なる各領域毎の凍結線膨張率を，凍土成長時期および凍結管の配置に対応した2種類の冷却面形状を用いて計算し，3次元弾性FEMに適用した．この方法で凍結管の設置方向が異なる二つの現場を解析し，計測値との比較から解析精度を確認した．また，熱流方向にのみ凍結膨張するとした解析，等方膨張するとした解析とも比較して，本解析の有効性と妥当性を検証した．

A clinicopathological study was done on 85 Japanese patients with IgA glomerulonephritis. Of patients with glomerulonephritis whose clinical course is of slow progression, the presence of IgA glomerulonephritis was demonstrated immunohistologically. The majority of such patients presented with a mild degree of proteinuria and/or persistent microscopic hematuria. In 15% of the patients, recurrent gross hematuria was noted. These findings suggest that immunohistological study is important in dealing with adult patients with so-called idiopathic renal hematuria. Light-microscopic findings of IgA glomerulonephritis were divided into 4 groups. In 56% of the patients, diffuse stalk thickening of the mesangium was noted and in one third of them, small crescent formations were present. In 22% of the patients, focal segmental proliferation was noted. Diffuse mesangial deposition of IgA noted by immunofluorescence was considered to correspond to the characteristic nodular deposition detected by light microscopy and to the relatively large globular hemispheric deposits detected by electron microscopy.

Code clones represent one factor that makes software maintenance difficult. A code clone represents an identical or similar portion in source code. If a bug is present in a code portion, then all of the code clones with that code portion must be considered for revision. However, in a large-scale software system, finding all the sites by hand and evaluating them for revision is extremely difficult. In this paper, the authors develop Gemini, a code clone analysis environment, which uses the results of detection from a code clone detection tool, CCFinder. In the authors' system, functions to visualize position information for code clones, to calculate metrics values for code clones, and to reference the corresponding source code are available to support the use of code clones in development and maintenance. In a case study using the system, the authors confirmed that characteristic code clones can be extracted. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 89(11): 10–18, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20279

application/pdf, テクニカルレポート, 現在のソフトウェア開発では, 設計にはUMLを用いるのが一般的である.設計作業にはUML設計とUI設計を含むにもかかわらず, 最初からUML設計にUI設計を取り入れた設計作業を支援するようなツールは見当たらない.そこで本研究では, UML設計とUI設計の関連情報にUML設計で用いるメソッドとUI設計で用いるウィジットのリンクを取り上げ, これらの関連情報を入力できるような設計支援ツールを提案する.本支援ツールにより, UML設計とUI設計の関連情報を入力しUML設計の中に残すことができる.その上で設計作業することで, 外部仕様と内部仕様のつなぎ目の検討漏れなどを防ぐことができ, 設計の精度を高めることができる., In current software development, it is general to use UML for the design. Though UML design and UI design are contained in the design work, we have not found the tool which supports the design work that UI design was adopted in the UML design from the beginning. So, we take up the link of a method in the UML design and a widget in the UI design as a related information of the UML design and the UI design, and propose the design support tool which can input this related information in this research. This support tool can keep the input of related information in the UML design. By using this tool, we can prevent the examination omission of the item which becomes the joint of the external specifications and the internal specifications and enhance the precision of the design.

We previously demonstrated that Xenopus sperm undergo an acrosome reaction on the vitelline envelope (VE) in response to the materials secreted from the oviductal pars recta [Dev. Biol. 243 (2002), 55]. A monoclonal antibody against the acrosome reaction-inducing substance in Xenopus (ARISX) was obtained by immunizing mice with pars recta extract (PRE). The acrosome reaction by PRE or on the VE was effectively inhibited by the intact anti-ARISX antibody as well as its Fab fragment, indicating that the antibody recognizes the epitopes localized on the acrosome reaction-inducing substance. On Western blots, the anti-ARISX antibody recognized a molecule with an apparent molecular mass of 300 kDa in PRE and in the VE, but this molecule was not detected in the coelomic envelope. The amount of ARISX in PRE was increased by the treatment of females with pregnant mare serum gonadotropin. Periodate oxidation of PRE completely abolished the acrosome reaction-inducing activity, indicating the involvement of the carbohydrate moieties of ARISX in inducing the acrosome reaction. On immunofluorescence observation, ARISX was localized in the epithelial cells in the posterior region of the pars recta and on the VE as fibrous structures.

Previous electron microscopic observations have shown that the acrosome of the sperm of the frog, Xenopus laevis, comprises a membrane-bounded vesicle covering the anterior-most position of the head. We obtained a sperm suspension from the testes and stained it with LysoSensor Green for observation under a confocal laser scanning microscope and found a bright fluorescence reflecting the presence of the acrosomes at the top of the sperm head in about 64% of the sperm, with no deterioration of their capacity to fertilize. About 40% of the sperm with an acrosome underwent an acrosome reaction in response to Ca2+ ionophore A23187, as evidenced by a loss of LysoSensor Green stainability, accompanied by breakdown of the acrosomal vesicle. About 53% of the sperm bound to isolated vitelline envelopes underwent an acrosome reaction, whereas both jelly water and solubilized vitelline envelopes weakly induced an acrosome reaction. When the sperm were treated with an oviductal extract obtained from the pars recta, but not the pars convoluta region, about 40% of the sperm with acrosomes underwent an acrosome reaction. The substance containing acrosome reaction-inducing activity in the pars recta extract seemed to be a heat-unstable substance with a molecular weight of greater than 10 kDa. The activity was not inhibited by protease inhibitors but required extracellular Ca2+ ions. These results indicate that the acrosome reaction occurs on the vitelline envelopes in response to the substance deposited from the pars recta during the passage of the oocytes through the oviduct.

Helical gear transmission error was measured with gear meshing to assess the validity of the conventional numerical analysis of gear meshing. For high-accuracy measurement, high-performance laser rotary encoders, a rigid gear box and rigid gear shafts were used. Three gear pairs with different tooth flank modifications were tested. Alignment errors of test gear pairs were also measured, and considered in the numerical analysis. The numerical analysis assessed is based on Umezawa and Kubo's theory that regards the gear tooth as a plate in deflection analysis. In both the test and the calculation, the amount of transmission error changed according to the working torque, and decreased under some torque conditions. The calculated results corresponded well to the measured results, and numerical analysis proved satisfactory validity for practical use. The slight discrepancy in the results would be reduced by improving the contact and bending deformation of the gear tooth in the numerical analysis.

Various models have been proposed for frost heave estimation. However, a practical evaluation method for multi-dimensional deformation has not yet been established. This study aimed to discuss the possibility of expanding an existing evaluation method into three dimensions based on previous experience on simulating interactive behavior between an underground structure and frost heave. Takashi’s equation was adopted among several frost heave models considered; this model has been used to estimate one-dimensional frost heave according to the Japanese Geotechnical Standard. However, it is applicable only for one-dimensional frost heave. The authors developed a new apparatus to measure three-dimensional frost heave to apply Takashi’s equation to multi-dimensional heave, and a modified equation was proposed based on the experimental results. Considering the effect of anisotropic properties on frost heave, this proposal was adopted for a simulation program by coupling the heat transfer calculation and mechanical equilibrium analysis in a finite element method (FEM) model. The fundamental simulation results are presented in this paper as an example to confirm the proposed model’s applicability.

Various models have been proposed for frost heave estimation. However, a practical evaluation method for multi-dimensional deformation has not yet been established. This study aimed to discuss the possibility of expanding the existing evaluation method into three dimensions based on previous experience on simulating interactive behavior between a chilled gas pipeline and frost heave. Takashi's equation was adopted among several frost heave models considered; this model has been used to estimate one-dimensional frost heave according to the Japanese Geotechnical Standard. A new three-dimensional frost heave apparatus was developed to apply Takashi's equation to multi-dimensional heave, and a modified equation was proposed based on the experimental results. Considering the effect of anisotropic properties on frost heave, this proposal was adopted for a simulation program by coupling the heat transfer calculation and mechanical equilibrium analysis in a finite element method (FEM) model. The simulation results are presented in this paper as an example to confirm the proposed model's applicability.

飽和土の凍結膨張特性に及ぼす各方向の応力の影響を調べる目的で,熱流方向の拘束応力σ1及び熱流と直角方向の拘束応力σ3を任意に与える開放型の凍上実験(三軸凍上実験)を行った.凍結膨張は,熱流方向だけでなく,熱流と直角の方向にも起こり,各方向の凍結膨張はσ1,σ3に依存した.σ1が増加すると,熱流方向の凍結膨張率ξ1は減少し直角方向の凍結膨張率ξ3は増加したが,σ3が増加すると,ξ1は増加しξ3は減少した.また凍結膨張率ξvは,σ1またはσ3の増加によって減少したが,あるσ1,σ3以上では減少しなくなる傾向が見られた.ξ1,ξ3各々について,σ1,σ3の関数形として表される実験式で,実験結果を整理する事が出来た.この実験式においてξ3を0とすると,別に行った従来のシリンダーに収納する凍上実験(一軸凍上実験)の結果と良く一致した.

The Working Party for Legionellosis headed by the Japanese Ministry of Health and Welfare processed to standardize the diagnostic procedures for Legionella pneumonia, as the first step to clarify the actual occurrence of patients with this respiratory disease. All the clinical data were collected and analysed on the 28 culture-confirmed patients in Japan during the past 11 years, from 1980 through 1990. The 28 patients were distributed throughout Japan, from Hokkaido to Kyushu. Out of 28 patients, 18 were community-acquired and 10 were nosocomially infected. In 8 of 18 community-acquired patients, any significant underlying disease was not observed. Though it was dominant in the age group in their 60s & 70s, victims were distributed in adults over 20 years of age and even in a new born baby. Only 5 out of 28 patients recovered successfully. From the autopsy findings, in 5 out of the remaining 23 expired patients, Legionella pneumonia seemed to be successfully treated, but other disease or other bacterial pneumonia put an end to the patients. The results of clinical laboratory tests and the efficacy of antibiotics to Legionella pneumonia were essentially the same as those reported in the literature.

We analyzed the initial and follow-up chest radiographs of 28 patients with culture-positive Legionella pneumonia, and developed a scoring system to quantitate the severity of radiological findings for pneumonia. Intrapulmonary shadows were observed on the initial chest radiograph in 26 patients, but pleural effusion was noted in only one. In one patient the initial chest radiograph had probably been obtained too early to reveal any pulmonary change. Alveolar shadows were noted on the initial radiograph in 21 (81%) patients, and interstitial shadows in 5 (19%). In ten (38%) patients shadows were present in both lung fields. Shadows were prominent in the middle and lower lung fields. A cavity was noted in only one patient, and pleural effusion was also noted at some time during the clinical course in 19 (70%). A large amount of pleural effusion was observed in four patients. The average pneumonia severity score was 3.3 in the 9 patients who survived, and 5.1 in the 17 who died (p > 0.05). The mortality rate was 53% in the 17 patients with pneumonia severity score of 5 or less and 89% in the 9 patients with a score of 6 or more (p > 0.05). Twelve patients died within one week after the initial chest radiograph was obtained. There were no differences among patients with community-acquired infection with or without underlying disease and those with nosocomial infection in characteristic and extension of shadow, presence of pleural effusion, or pneumonia score. The chest radiograph of Legionella pneumonia include bilateral shadow findings characteristic, pleural effusion and rapid progression of shadow, and are clinically useful for diagnosis.