Learning from other disciplines [requirements engineering]

The requirements engineers mustn't be concerned with just technical issues such as traceability and measurability; neither focus on individual or group behavior. The requirements engineering should be seen as a sociotechnical discipline that requires diverse skills and knowledge. In this article the author reviews past columns, highlighting what we've learned from other disciplines and considering how we can further enrich our knowledge.     

Seeing more of the world [requirements engineering]

Requirements engineering experience shows that failure to look at all aspects of the problem space results in missing or incorrect requirements. The author provides a systematic approach for identifying which parts of the world require your attention, along with some easily applied heuristics for discovering whether you've looked far enough.     

Are we afraid of the dark [requirements]

Why don't we look into the dark? Are we afraid that it represents an unknown quantity and is therefore dangerous? If we have little time before our deadline, do we want to spend it looking into areas that our tools and methods don't mention? The answer depends on the kind of product you intend to build. If your product is to be the seventh incarnation of the payroll system that your company first implemented in 1976 and has changed very little in the intervening years, then look no further. If you want your next product to anticipate the future, to be one that its users like, to offer significant advantages to your organization, then requirements has to take on a different meaning. It has to mean looking into areas that are vague or unexplored, poking into the unlit corners to discover dark secrets, and inventing what your users never dreamed of     

Developer-focused assurance requirements [Evaluation Assurance Level and Common Criteria for IT system evaluation]

In 1999, the International Organization for Standardization and the International Electrotechnical Commission jointly published the Common Criteria for Information Technology Security revaluation to provide IT security evaluation guidelines that extend to an international community. The assurance requirements, including prepackaged sets of Evaluation Assurance Levels (EALs) in the Common Criteria (CC), represent the paradigm that assurance equals evaluation, and more evaluation leads to more assurance. This paradigm is at odds with the commercial off-the-shelf (COTS) marketplace, neither reflecting how confidence is typically achieved nor providing a cost-effective means for supplying grounds for confidence in the security capabilities of the information technology being evaluated.     

Inquiry-based requirements analysis

This approach emphasizes pinpointing where and when information needs occur; at its core is the inquiry cycle model, a structure for describing and supporting discussions about system requirements. The authors use a case study to describe the model's conversation metaphor, which follows analysis activities from requirements elicitation and documentation through refinement     

Reframing requirements analysis

How can software development be reframed as a goal-seeking dialogue? As an example the author considers requirements analysis and documentation. He presents a depiction of requirements evolution as a dialogue, rather than as a monolithic plane     

The user experience [Internet]

In this article the author provides perspective on user experience, usability and user-centered design. User experience is a broad collection of user-centric issues that cut through the full extent of a project. The author points out new developments in the user experience world that are opening up new opportunities for research and projects. The author also discusses how good user experience processes can be built into the kinds of system development projects that many of us are involved in.     

一款IP电话机的需求分析设计

需求分析与规格说明是嵌入式产品开发的一个重要环节。本文以一款IP电话机为例,通过"需求分析与概念性规格说明"以及"图形化规格说明"两部分来介绍这阶段工作要点。     

Flexibility as a design driver [systems analysis]

Ambiguous requirements and those that emerge late in the design cycle often complicate development and throw off established schedules. The authors describe how reformulating information missing at the design stage into a flexibility requirement can turn the absent data into a design driver. Designers constantly run into issues that have yet to be understood through specification, system design, or standardization. Changes in evolving technologies and businesses often result in unstable system requirements. Reliable hardware or mechanical details might not be available until very late in the development process. Yet engineers must initiate software development even though some subsystem details have not yet been completely defined. Missing information and related flexibility requirements can lead to a design plagued by many well-known problems that affect performance, modularity, scalability, and clear separation of concerns. In some cases, developers must sacrifice rules of thumb to maintain planned development schedules. Providing flexibility for everything in the system isn't possible, so developers will always need to determine the static requirements and explicitly state where continued development and rapid modification require flexibility     

DBMS[me] [life-time records]

The article is concerned with time and the deluge of data that we can expect to collect and view. We examine this from the perspective of a subproblem, a database management system that records a person's life in its entirety - referred to here as DBMS[me] and E-me (that is, a database of me or an electronic model of me). Challenges for the DBMS[me] are to augment human memory by recording all data about an individual, to organize such data into models, and to develop security and privacy languages to control access to such models.     

The Voxar project [parallel ray-tracing]

An implementation of the ray-tracing algorithm that is based on the Voxar parallel processing model, which simulates 3D physical phenomena, is discussed. The implementation of a general parallel ray-tracing program, and the implementation of Voxar are reviewed. Results of a performance evaluation of Voxar show that the machine's best points are its efficiency on complex ray-tree images and its parallel animation functionality. Its weak points are the insufficiency of the deadlock prevention strategy, the high cost of the communication system, the sequential generation of the primary rays, and the rigidity of the regular subdivision