Semi-automated model matching using version difference

Interoperability of software is a critical requirement in the architecture, engineering, and construction (AEC) industry, where a number of data exchange standards have been created to enable data exchange among different software packages. To be able to comply with existing data exchange standards, the software developers need to match their internal data schemas to the schema defined in a standard and vice versa. The process of matching two large scale data models is time consuming and cumbersome when performed manually, and becomes even more challenging when a source and/or a target model is being updated frequently to meet the ever expanding real world requirements. While several prior studies discussed the need for approaches toward automated or semi-automated schema matching, an approach that builds on existing matches between two models has rarely been studied. In this paper, we present a semi-automated approach for model matching. This approach leverages a given set of existing matching between two models and upgrades those matching when a new version of a target model is released. The paper describes in detail a list of upgrade patterns generated and validated through a prototype by matching a domain-specific data model to several recent releases of the industry foundation classes.     

Recommending software upgrades with Mojave

Software upgrades are frequent. Unfortunately, many of the upgrades either fail or misbehave. We argue that many of these failures can be avoided for users of the new version of the software by exploiting the characteristics of the upgrade and feedback from the users that have already installed it. To demonstrate that this can be achieved, we build Mojave, the first recommendation system for software upgrades. Mojave leverages data from the existing and new users, machine learning, and static and dynamic source analyses. For each new user, Mojave computes the likelihood that the upgrade will fail for him/her. Based on this value, Mojave recommends for or against the upgrade. We evaluate Mojave for three real upgrade problems with the OpenSSH suite, and one synthetic upgrade problem each in the SQLite database and the uServer Web server. Our results show that it provides accurate recommendations to the new users.     

OWL文件向关系数据库的映射及存储研究#br#

 针对现有本体存储模式存在的无法推理及操作不便等缺陷,本文提出一种新的OWL（Web Ontology Language）文件向关系数据库映射及存储的模式。该模式将本体文件数据提取至由本体ER图（Entity Relationship Diagram）设计的底层数据库中,同时在提取过程中自动获取隐含语义数据,再将底层数据库中的数据映射为便于用户操作的数据库。实验结果表明,该模式既保留了本体文件的隐含语义,又提高了查询效率,同时极大地方便了普通用户对本体数据的操作。     

Co-transformations in Information System Reengineering

Database reengineering consists of deriving a new database from a legacy database and adapting the software components accordingly. This migration process involves three main steps, namely schema conversion, data conversion and program conversion. This paper explores the feasibility of transforming the application programs through code transformation patterns that are automatically derived from the database transformations. It presents the principles of a new transformational approach coupling database and program transformations and it describes a prototype CASE tool based on this approach.     

Deciding to upgrade packaged software: a comparative case study of motives,contingencies and dependencies

Packaged software is widely adopted and has become an integral part of most organizations’ IT portfolios. Once packaged software is adopted, upgrades to subsequent versions appear to be inevitable. To date, research on packaged software has not paid attention to the upgrade decision process. To explore this area, we studied cases of upgrades to two widely used packaged software products (SAP and Windows) in a multi-billion dollar division of a Fortune 500 company. From an analysis of the cases, we induced a theoretical model explaining the influences affecting the decisions to upgrade. Our model suggests that upgrade decisions are the outcome of interaction between motivating forces that can originate from internal and external environments, and contingency forces. Business need was found to be one of the key internal requirements, along with organizational risk mitigation policies. Organizational reliance on packaged software also creates dependence on vendors that gives them influence over the organization's upgrade decision. The decision to upgrade is also contingent on the availability of internal resources. Although scarcity of internal resources can postpone an upgrade when the need to upgrade is deferrable, organizations will prioritize internal resources when the upgrade is deemed necessary.     

Monitoring applications: An immune inspired algorithm for software-fault detection

Large-scale software systems are in general difficult to manage and monitor. In many cases, these systems display unexpected behavior, especially after being updated or when changes occur in their environment (operating system upgrades or hardware migrations, to name a few). Therefore, to handle a changing environment, it is desirable to base fault detection and performance monitoring on self-adaptive techniques.Several studies have been carried out in the past which, inspired on the immune system, aim at solving complex technological problems. Among them, anomaly detection, pattern recognition, system security and data mining are problems that have been addressed in this framework.There are similarities between the software fault detection problem and the identification of the pathogens that are found in natural immune systems. Being inspired by vaccination and negative and clonal selection observed in these systems, we developed an effective self-adaptive model to monitor software applications analyzing the metrics of system resources.     

HLA中基于OMT文件创建数据库关系表的方法

针对高层体系结构（HLA）仿真结果数据日益增多,数据类型多变以及数据关系极其复杂的情况,介绍了利用HLA中对象模型模板（OMT）文件创建数据库关系表的通用方法。根据一般关系表的创建过程,分析了利用OMT文件中的数据定义,分别确定数据库关系表名称、字段名以及字段类型的原理。对OMT中类名过长及重复的问题,设计采用映射表的处理方法。对OMT文件中比较复杂的定义类型,包括多粒度或变粒度下简单数据类型、复杂数据类型以及嵌套复杂数据类型,详细分析了其对应的建表设计方案。最后根据实际仿真的需要,说明了关系表附加字段的选取过程。根据上述思路,设计开发了对应的工程软件,软件的成功应用证明了设计方案的有效性。     

Artexte metadata conversion to EPrints: adaptation of digital repository software to visual and media arts documentation

The following research questions structured our analysis: Does an open access institutional repository model respond to the needs of a non-academic documentation centre? Is EPrints software a good match to support the needs of the existing metadata describing Artexte’s collection? What are the customizations required to accommodate the existing Artexte metadata using EPrints? In order to address these questions, in this study we exported the existing metadata schema and sample data in Artexte’s three databases, performed a manual evaluation of metadata quality and compared the 49 Artexte fields to those available within the EPrints schema. We identified the metadata elements that mapped by default without the need for customization or modification and those which would need to be added to EPrints using configuration files. We also identified the customized software development to accommodate Artexte metadata using EPrints: the bilingual controlled vocabulary demands an extension of the EPrints subject taxonomy model with thesaurus semantic relationships. Comparing Artexte and EPrints metadata schemas, we found that 15 out of 49 fields mapped by default without the need for modification, 25 fields would need to be added to EPrints configuration files, and one field will be removed during the migration. With only the remaining eight fields requiring some special attention, we conclude that EPrints is suitable to the needs of Artexte’s bibliographic data management.     

Domain-knowledge-guided schema evolution for accounting database systems

The static meta-data view of accounting database management is that the schema of a database is designed before the database is populated and remains relatively fixed over the life cycle of the system. However, the need to support accounting database evolution is clear: a static meta-data view of an accounting database cannot support next generation dynamic environment where system migration, organization reengineering, and heterogeneous system interoperation are essential. This paper presents a knowledge-based approach and mechanism to support dynamic accounting database schema evolution in an object-based data modeling context. When an accounting database schema does not meet the requirements of a firm, the schema must be changed. Such schema evolution can be realized via a sequence of evolution operators. As a result, this paper considers the question: what heuristics and knowledge are necessary to guide a system to choose a sequence of operators to complete a given evolution task for an accounting database? In particular, we first define a set of basic evolution schema operators, employing heuristics to guide the evolution process. Second, we explore how domain-specific knowledge can be used to guide the use of the operators to complete the evolution task. A well-known accounting data model, REA model, is used here to guide the schema evolution process. Third, we discuss a prototype system, REAtool, to demonstrate and test our approach.     

Development of an integrated information model for computer integrated manufacturing

The development of an FDBS is integrate existing CIM components by using a bottom-up development process. The components used in this paper do not support any kind database management. The integration of those components into a federation may be done by using two general approaches [3]:

• • Migration of the files to a DBMS

• • Extend the file system to support DBMS-like features

Both migration and extension of the file system are costly solutions and actually depend on existing capabilities of the components. Problems may occur when the federated schema becomes too large. The schema might be split up into smaller federated schemes (loosely coupled FBDS).     

基于QTP的企业级应用软件自动化测试方法

针对目前软件版本频繁升级,测试周期不断压缩,测试工作量大的问题,结合一款企业级应用软件,基于QTP技术平台,搭建了自动化测试框架.首先,通过了解QTP的工作原理,结合企业级应用软件特点,设计了一款合适的自动化测试框架;然后,通过设计测试用例,编写脚本,执行脚本等过程实现了自动化测试.实践表明当自动化测试执行次数越多,自动化测试耗时基本是手工测试耗时的15%,即自动化测试更适合用于回归测试中.通过自动化测试框架的使用,解决了在短时间内完成大量测试用例覆盖的问题,保证了发布软件的质量,提升了测试效率.     

A quantitative look at software licensing for IT managers

Information vendors, buyers, and users often take the approach that the number of employees equals the number of licensed users. Unfortunately, although assuring virtually unlimited usage of the software or database, this approach can also come with an unlimited cost. A typical vendor contract might read something to the effect that "Vendor A agrees to provide unlimited access to database B for all 200 employees of Firm Z," a relatively straightforward approach. However, there is no logical reason to pay for unused information and access.     

An exploratory study of api changes and usages based on apache and eclipse ecosystems

Frameworks are widely used in modern software development to reduce development costs. They are accessed through their Application Programming Interfaces (APIs), which specify the contracts with client programs. When frameworks evolve, API backward-compatibility cannot always be guaranteed and client programs must upgrade to use the new releases. Because framework upgrades are not cost-free, observing API changes and usages together at fine-grained levels is necessary to help developers understand, assess, and forecast the cost of each framework upgrade. Whereas previous work studied API changes in frameworks and API usages in client programs separately, we analyse and classify API changes and usages together in 22 framework releases from the Apache and Eclipse ecosystems and their client programs. We find that (1) missing classes and methods happen more often in frameworks and affect client programs more often than the other API change types do, (2) missing interfaces occur rarely in frameworks but affect client programs often, (3) framework APIs are used on average in 35 % of client classes and interfaces, (4) most of such usages could be encapsulated locally and reduced in number, and (5) about 11 % of APIs usages could cause ripple effects in client programs when these APIs change. Based on these findings, we provide suggestions for developers and researchers to reduce the impact of API evolution through language mechanisms and design strategies.     

A unit test approach for database schema evolution

Context

The constant changes in today’s business requirements demand continuous database revisions. Hence, database structures, not unlike software applications, deteriorate during their lifespan and thus require refactoring in order to achieve a longer life span. Although unit tests support changes to application programs and refactoring, there is currently a lack of testing strategies for database schema evolution.

Objective

This work examines the challenges for database schema evolution and explores the possibility of using various testing strategies to assist with schema evolution. Specifically, the work proposes a novel unit test approach for the application code that accesses databases with the objective of proactively evaluating the code against the altered database.

Method

The approach was validated through the implementation of a testing framework in conjunction with a sample application and a relatively simple database schema. Although the database schema in this study was simple, it was nevertheless able to demonstrate the advantages of the proposed approach.

Results

After changes in the database schema, the proposed approach found all SELECT statements as well as the majority of other statements requiring modifications in the application code. Due to its efficiency with SELECT statements, the proposed approach is expected to be more successful with database warehouse applications where SELECT statements are dominant.

Conclusion

The unit test approach that accesses databases has proven to be successful in evaluating the application code against the evolved database. In particular, the approach is simple and straightforward to implement, which makes it easily adoptable in practice.     

A framework for object migration in object-oriented databases

This article presents a framework developed for accomodating various object migrations in ‘statically-typed’ object databases. Requirements for supporting object migrations are stipulated, and a conceptual model for describing and facilitating different kinds of migrations is described. Associated issues of controlling such migrations are then addressed, along with an initial investigation on the interence of implied migration paths and the completeness of migration operators. Some guidelines are then given to help users conduct migrations more effectively. An implementation prototype on top of an object-oriented database system was built, which embodies full support of all migration types specified in the migration model.     

An adaptive plan-oriented and continuous software migration to cloud in dynamic enterprises

Replacing existing software/hardware components with their equivalent cloud services is an important decision faced by IT managers in today's enterprises. A variety of possible migration targets and cloud services with too many configurations and cost models, disparate and changing strategic objectives of the enterprise management that triggers the migration process, and the complex structure of the legacy applications make software migration to the cloud a challenging issue. In contrast to the existing approaches that model the migration process as an optimization problem to find the optimal deployment of software components on cloud services without presenting a practical migration plan, in this paper, a plan-oriented migration approach is proposed by which the enterprise management is able to follow migration steps of a valid plan. All valid plans are modeled using a labeled transition system, and a recommender engine directs the management through the possible migration paths using predefined fitness functions. It was observed that, particularly in dynamic and changing conditions that a flexible migration plan is essential, the proposed plan-oriented method is very much effective in satisfying the enterprise strategic objectives. Evaluations have been performed using two quality indicators: total cost of ownership and scalability index.