データの格納および管理の手段として，RDBに代わり，高速に大量のデータを処理でき，分散化の容易なNoSQLデータベースが用いられてきている．しかしデータ構造や操作言語の違いから，システム移行は容易ではない．そこで本研究では，文を入力にとり，等価なNoSQLの問い合わせ文を出力する変換プログラムを作成した．対応するNoSQLはMongoDBとHBaseとし，実装において文の解析および言語間のコード断片の対応付けを行った．評価実験の結果，32例の文のうち，13例でMongoDB，9例でHBaseの問い合わせ文を生成できた．

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関係データベースの問合わせ言語に対して、本研究室では、演習者が書きこんだコマンドをデータベース上で実行する、演習システムをPHP5、PostgreSQL8.4という環境の下で開発した。開発された演習システムは本大学情報工学科の講義で利用され、一定の学習効果が得られている。 本論文では、用意された演習問題を全て解いた学生のために、演習者が自由にテーブルデータを登録してを実行できる、自由演習フォームの拡張を行っている。さらに、自由演習フォームのWebAPI化を行うことで、様々な学習サイトでの動作を確認することを可能としている

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Thinking process development diagram is a graphical expression from which readers can easily find not only the hierarchy of a given problem but the relationship between the problem and the solution. Although that has been developed as an idea creation support tool in the field of mechanical design, we referred to the restricted version as clamshell diagram to attempt to apply to other fields. In this paper we propose the framework for drawing the diagram of the statement. The basic idea is to supply the hierarchical code fragments of a given statement in the left side of the diagram and to put the meaning written in a natural language in the right. To verify the usefulness of the diagram expression, we actually drew several clamshell diagrams. For three statements that are derived from the same specification, the resulting diagrams enable us to understand the difference visually.

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本研究室では、関係データベース問い合わせ言語である「 言語」習得のために 演習システムを開発し、本大学情報工学科の講義で利用され、一定の学習効果も得られている。しかし、既存の演習システムではselectというコマンドしか実行できない。また、演習者が実行したコマンドが間違いだった場合、データベースシステムはエラー文を返すが、初心者にはどうして間違ったのか理解しづらいといった問題が存在する。そこで本発表では、実行可能なコマンドの増加によるシステムの機能強化と、エラー文の簡易化や、演習者が打ち込んだ文の全角スペースから半角スペースへの自動変換など、ユーザビリティの向上を行っている。

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The globalization of commerce has increased the importance of retrieving and updating complex and distributed information efficiently. Web services currently show that the most promise for building distributed application systems and model-driven architecture is a new approach to developing such applications. The expanding scale and complexity of enterprise information systems (EISs) under distributed computing environments has made sharing and exchanging data particularly challenging. Data services are applications tailored specifically for information oriented tasks to deal with business service requirements, and are heavily dependent on the distributed architecture of consumer data processing. The implementation of a data service can eliminate inconsistency among various application systems in the exchange of data. This paper proposes a data-oriented model-driven developmental framework to deal with these issues, in which a platform independent model (PIM) is divided into a service model, a logic data model, and a service composition model. We also divide a platform specific model (PSM) into a physical data model and a data service model. In this development method, we define five meta-models and outline a set of rules governing the transformation from PIMs into PSMs. A code generator is also included to transform each PSM into the application code. We include a case study to demonstrate the feasibility and merits of the proposed development framework with a case study.

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Huge volumes of bioinformatics data are emerging from sequencing efforts, gene expression assays, X-ray crystallography of proteins, and many other activities. High-throughput experimental methods produce masses of data, so that the whole of biology has changed from a data-light science into a data-driven science. Currently there are a lot of databases and software tools dealing with these genomic data. In general, each tool and database uses a different type of data in exchange protocols, and usually they offer specific services. These Databases are design with different languages and run on different operating systems. Therefore biologists are in a difficult situation where they have to use, process and store heterogeneous data when using heterogeneous software tools and databases. Our framework, GenoMEDIA provides two main middleware to help for this integration, Lydia and Antje. On the one hand, the Lydia middleware offers us facilities for working simultaneously with a variety of Services and Databases. On the other hand, the Antje one ,with the concept of remote view, is designed to allow users to manage multiple heterogeneous remote databases in a uniform vision. The aim of this paper is to present GenoMEDIA and how heterogeneous databases and remote services are integrated, in particular how Antje was designed, implemented and tested with various genomic databases.

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問題解決を行う方法論の中に, 形式的アプローチによる問題解決の方法論の研究があり, データ処理の取り扱いの重要性については "モデル理論によるデータ処理システムの設計 (高木徹)" にて説明が行われるが, 本論ではその実装に焦点を当てる. 実装に際して Z を導入した際の利点を生かし, web 上の情報システムの実装例を行ったことについて説明する.

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A digital twin for Aluminium billet DC-casting, a digital replica of the physical casting process, creates a living simulation platform that can analyse,

, and change the process to achieve the multi-objectives process optimization. In this work, we assess the possibility of integrating high throughput micro-macro scale computation, database and an artificial neural network (ANN) to establish an analytical twin for the prediction of a typical Direct Chill casting defect of Al alloys, i.e., hot tearing. The high throughput computation consists of solidification path computation at the microscopic scale (dendrite arm scale with software Alstruc) and heat transfer, fluid flow and stress/strain computation at the macroscopic scale (the scale of billet/ingot dimensions with software Alsim). The two-scale computations are coupled via sharing with Alsim the compositional dependent solidification path (Solid fraction-Temperature curve), thermo-physical properties such as densities, thermal conductivities calculated by Alstruc. Then Alsim calculates all the field variables including thermal stress, volumetric strain, and predicts the locations of the most vulnerable position and its hot tearing susceptibility. We demonstrate that the proposed framework can efficiently predict sump depth and hot-tearing tendency in the center of billets for a range of industrial AA6xxx alloy composition, casting parameters including casting speed and casting temperature. The data generated by the multi-scale computation are used to build a database for training and testing the neural network. The utilities of the trained neural network and established database are discussed for their application to optimize DC casting recipes of 6xxx extrusion billets. Our conclusion is that the proposed high throughput multi-scale simulation, SQLite database and ANN parameterization are three essential pillars supporting the establishment of a digital casting twin, and such a twin can provide a quick screening and selection/adjustment of process parameters before casting or during casting to avoid hot-tears.

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We proposes a method for determining the frequency for monitoring the activities of a malware download site used for malware attacks on websites. In recent years, there has been an increase in attacks exploiting vulnerabilities in web applications for infecting websites with malware and maliciously using those websites as attack platforms. One scheme for countering such attacks is to blacklist malware download sites and filter out access to them from user websites. However, a malware download site is often constructed through the use of an ordinary website that has been maliciously manipulated by an attacker. Once the malware has been deleted from the malware download site, this scheme must be able to unblacklist that site to prevent normal user websites from being falsely detected as malware download sites. However, if a malware download site is frequently monitored for the presence of malware, the attacker may sense this monitoring and relocate that malware on a different site. This means that an attack will not be detected until the newly generated malware download site is discovered. In response to these problems, we clarify the change in attack-detection accuracy caused by attacker behavior. This is done by modeling attacker behavior, specifying a state-transition model with respect to the blacklisting of a malware download site, and analyzing these models with synthetically generated attack patterns and measured attack patterns in an operation network. From this analysis, we derive the optimal monitoring frequency that maximizes the true detection rate while minimizing the false detection rate.

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The DNA database has been managed in a flat-file system at the DDBJ since 1985. The flat-file system is inadequate for building and searching the DNA database which is receiving an explosive increase entries. We carried out a transformation from the flat-file system to the relational database system with GenBank staff. The schema of the relational database was designed as follows:
(1) Decomposing the DNA data into both structuralized and non-structuralized data
(2) Partitioning large tables into small tables without anomaly
(3) Making a flexible relationship among tables to represent complex data
This schema provided the capability for building and searching the DNA database with less memory on the relational database system. However, the schema was implemented as a complex network structure with about 60 tables. It is difficult to use the search language of the relational database system with this schema.
We defined and simplified the schema for easy use of the commands using the view function of the relational database system on the existing schema. The simplified schema implemented in the view function was defined as LOCUS, DEFINITION, ACCESSION, KEYWORDS, SOURCE, REFERENCE, FEATURES, ORIGIN, and SEQUENCE tables which are virtual tables without storing real data. It represents aspects of the traditional DDBJ/EMBL/GenBank data format which are familiar to biologists using the flat-file system.
Users can easily join these virtual tables using attribute storing accession numbers. Since we developed the simplified schema, users are able to use the search command easily and get quick response in DNA data searches.

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Web application second-order vulnerabilities first inject malicious code into the persistent data stores of the web server and then execute it at later sensitive operations, causing severe impact. Nevertheless, the dynamic features, the complex data propagation, and the inter-state dependencies bring many challenges in discovering such vulnerabilities. To address these challenges, we propose DISOV, a web application property graph (WAPG) based method to discover second-order vulnerabilities. Specifically, DISOV first constructs WAPG to represent data propagation and inter-state dependencies of the web application, which can be further leveraged to find the potential second-order vulnerabilities paths. Then, it leverages fuzz testing to verify the potential vulnerabilities paths. To verify the effectiveness of DISOV, we tested it in 13 popular web applications in real-world and compared with Black Widow, the state-of-the-art web vulnerability scanner. DISOV discovered 43 second-order vulnerabilities, including 23 second-order XSS vulnerabilities, 3 second-order

injection vulnerabilities, and 17 second-order RCE vulnerabilities. While Black Widow only discovered 18 second-order XSS vulnerabilities, with none second-order injection vulnerability and second-order RCE vulnerability. In addition, DISOV has found 12 0-day second-order vulnerabilities, demonstrating its effectiveness in practice.

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Hibernate上でポータブルなデータベースガーベジコレクション(DBGC)を実現した．本ソフトウェアは，ミドルウェアとして利用するHibernateがDBの差異を吸収することでポータブル性を実現している．Hibernateが保有する完全なテーブル間関連のメタデータを利用してGCを実現するために必須の到達可能経路情報を獲得している．GCのアルゴリズムは湯淺のsnapshot-at-the-beginning法を用いた．マーキングはを用いた集合演算によって行っている．GCのマークを世代番号として表現した整数値のマーキングフラグを導入したことで，スイープを通常のmark-and-sweep法の順序とは異なり，任意のタイミングで行うことができる．オブジェクトの新規追加とポインタの参照先の付け替えに関する情報はHibernateが持つオブジェクトの状態監視機構を改変して獲得している．世代番号の制御によってDBアプリケーションと並列にGCを行うことができる．

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We present a flexible framework for evaluating data-dependent access control systems. Based on logical formalism, the framework is general enough to simulate all existing systems. In this paper, we analyze and compare currently available access control systems and demonstrate how they can be simultaneously extended and simplified using our framework. A series of examples and a cross-comparative analysis clearly demonstrate the advantages of our framework over previous methods.

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Recently, a graph labeling technique based on prime numbers has been suggested for reducing the costly transitive closure computations in RDF query languages. The suggested prime number graph labeling provides the benefit of fast query processing by a simple divisibility test of labels. However, it has an inherent problem that originates with the nature of prime numbers. Since each prime number must be used exclusively, labels can become significantly large. Therefore, in this paper, we introduce a novel optimization technique to effectively reduce the problem of label overflow. The suggested idea is based on graph decomposition. When label overflow occurs, the full graph is divided into several sub-graphs, and nodes in each sub-graph are separately labeled. Through experiments, we also analyze the effectiveness of the graph decomposition optimization, which is evaluated by the number of divisions.

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With the extensive development of risk-informed application and the gradual implementation of technical policies for configuration risk management, risk monitor has gradually shifted from the original offline operation state to the online operation state, that is, integrated into the production activities of nuclear power plants. The calculation speed of real-time risk is generally required to be within 1-2 minutes; The risk monitor used in domestic and foreign basically meet this requirement. However, in multi-task scenarios, such as a risk assessment of maintenance plan, such speed is still far from meeting the application requirements. In addition, how to

the risk monitor database quickly and efficiently is also a problem faced by the risk monitor. Based on the application scenarios and calculation speed requirements of risk monitor, this paper studies an efficient method of database, an efficient algorithm of computing minimum cut set(MCS) and supporting multi-task scenarios after risk model reconstruction. Combined the latest computer technology, it improves the calculation speed of risk monitor, meets the speed requirements for efficient calculation of multi-task scenario risk, and provides data algorithm for the next stage of risk monitor development.

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NoSQL systems have become vital components to deliver big data services due to their high horizontal scalability. However, existing NoSQL systems rely on experienced administrators to configure and tune the wide range of configurable parameters for optimized performance. In this work, we present a configuration management framework for NoSQL systems, called xConfig. With xConfig, its users can first identify performance sensitive parameters and capture the tuned parameters for different workloads as configuration policies. Next, based on tuned policies, xConfig can be implemented as the corresponding configuration optimiaztion system for the specific NoSQL system. Also it can be used to analyze the range of configurable parameters that may impact the runtime performance of NoSQL systems. We implement a prototype called HConfig based on HBase, and the parameter tuning strategies for HConfig can generate tuned policies and enable HBase to run much more efficiently on both individual worker node and entire cluster. The massive writing oriented evaluation results show that HBase under write-intensive policies outperforms both the default configuration and some existing configurations while offering significantly higher throughput.

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WWWブラウザを介して履修申告を行うシステムが山梨大学に導入されたが、多人数で利用する際に十分な性能を発揮することができずに問題となった。本論文では WWW 技術を用いた履修申告システムの開発を通して、WWWとデータベースを連携させて3階層型クライアント・サーバ・システムを構築する際の注意点を考察する。その結果として、安価なハードウェアと無料のソフトウェアだけを用い、機能的にも現行システムと同等で圧倒的に性能の優れたシステムを構築することができた。また開発したシステムの性能評価を行うために、現実の多人数同時利用によるサーバへの負荷の発生と同等の状況を1人だけの操作によって作り出し、システムの性能評価を行える自動ベンチマークシステムも開発した。これによって試作履修申告システムの性能評価を行い、現行システムでの性能向上をはかるための方法について考察した。

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 遺伝的アルゴリズムを用いた看護師勤務表作成支援システムが実用化されつつある．しかし，評価関数が病院によって大きく異なるため，その記述には大変な手間がかかる．われわれは利用者が画面操作により評価関数を生成する手法を開発した．本手法は評価関数をにより記述し，評価関数をプログラム本体から分離することで，プログラムに変更を加えることなく評価関数の追加を行うことができる．による記述においては，入れ子構造や自己結合の記述方法を組み合わせることで評価関数を記述可能とした．また，の習得は利用者である看護師には困難であるので，画面操作によりを生成する手法を開発した．本手法により，利用者はを意識することなく評価関数を生成できることを示した．

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