Design breakdowns,scenarios and rapid application development

In this paper we consider the way in which two representational forms, scenarios and design breakdowns, which have emerged in the traditions of human-centred design are relevant within the recent commercial emphasis on rapid application development (RAD). RAD is a contingent approach to interactive software development that is characterised by large amounts of user involvement, incremental prototyping and product-based project management. Scenarios have become popular as an intermediate representation within the human–computer interaction and computer supported co-operative work communities. Design breakdowns have been suggested as a useful organising device and design technique within the co-operative prototyping literature. Both these representational forms are not currently utilised within the commercial RAD tradition. In order to detail the relevance of these concepts to commercial development, we describe the ‘natural history’ of one particular RAD project and show how scenarios, breakdowns and the resolution of such breakdowns contributed to the successful implementation of an information system within a small commercial organisation. We conclude with a discussion of lessons from our work and some intended future work in this area.     

Coherence- and correspondence-driven work domains: implications for systems design

A distinction is made between coherence- and correspondence-driven work domains. This novel domain taxonomy is used to argue that the widely accepted goal of making the interface representation compatible with the user's mental model is not always appropriate. For correspondence-driven domains, it is more meaningful to constrain design from the side of the work domain rather than from that of the user. The implications of the coherence/correspondence distinction for the modelling of work domains, for interface design in computer supported co-operative work, and for the development of a multidimensional taxonomy of work domains are also briefly pointed out. The discussion suggests that the correspondence/coherence taxonomy provides a powerful conceptual tool for addressing fundamental issues in human-computer interaction.     

Using memory and fuzzy rules in a co-operative multi-thread strategy for optimization

In this article, we analyze a co-operative multi-thread search-based optimization strategy, where each solver thread represents a different optimization algorithm (or the same one with different settings), and they are all controlled by a centralized co-ordinator. We also propose the use of memory to keep track of both the state of the individual threads and the obtained solutions. Based on this memory, a very simple fuzzy rule base is used to control the system behavior.We also present the results of three computational experiments. The first of these checks the strategy by comparing it with an independent search strategy and a sequential algorithm, and the superiority of the co-operative scheme is confirmed. The second analyzes how definition of the threads affects the quality of the results, and the importance of there being a balanced set between intensification and diversification is corroborated. The third explores the use of memory with two different fuzzy rules, and the results indicate that the best combination is to use memory together with two rules (solver dependent and solver independent ones) (although this combination should not be activated at the beginning of the search in order to avoid premature convergence).     

Adaptive fusion and co-operative training for classifier ensembles

In this paper, architectures and methods of decision aggregation in classifier ensembles are investigated. Typically, ensembles are designed in such a way that each classifier is trained independently and the decision fusion is performed as a post-process module. In this study, however, we are interested in making the fusion a more adaptive process. We first propose a new architecture that utilizes the features of a problem to guide the decision fusion process. By using both the features and classifiers outputs, the recognition strengths and weaknesses of the different classifiers are identified. This information is used to improve overall generalization capability of the system. Furthermore, we propose a co-operative training algorithm that allows the final classification to determine whether further training should be carried out on the components of the architecture. The performance of the proposed architecture is assessed by testing it on several benchmark problems. The new architecture shows improvement over existing aggregation techniques. Moreover, the proposed co-operative training algorithm provides a means to limit the users’ intervention, and maintains a level of accuracy that is competitive to that of most other approaches.     

协作式生成对抗网络

生成对抗网络（Generative adversarial nets,GANs）将生成模型与判别模型进行了巧妙结合,采用无监督的训练方式,通过相互对抗共同提高,其在学术界掀起了一股新的机器学习热潮.GANs的学习目标是可以完整拟合任意真实样本的数据分布,然而在实际当中,真实样本分布的复杂程度难以预计,容易发生模式坍塌（Mode collapse）等问题,从而导致结果冗余,模型不收敛等.为提高无监督条件下的GANs生成能力,减少或消除模式坍塌,本文提出一种全新的协作式生成网络结构,通过构建多个生成模型,引入协作机制,使得生成模型在训练过程中能够相互学习,共同进步,从而提高模型对真实数据的拟合能力,进一步提高生成质量.通过在三组不同类型的数据集上进行实验,分析对比结果后发现新模型在二维图像生成方面,特别是人脸图片,有着显著的效果,协作机制不仅可以加快模型收敛速度,提高训练效率,还能消除损失函数噪声,在三维模型生成方面也产生了一定的影响.通过调整模型参数,模式坍塌问题也得到了遏制.本文还设计了一种动态学习方法,动态调节模型的学习速率,有效减少了过大或过小的梯度惩罚.     

Information Flow for Optimized Management of Spectrum and Radio Resources in Cognitive B3G Wireless Networks

The Beyond 3G (B3G) radio landscape will consist of cognitive heterogeneous wireless networks, operating in the framework of diverse co-operative associations among different classes of operators and providers, for the accommodation of the demands of users with multimode and/or multihoming enabled terminals. In this context, the optimized spectrum and radio resource utilization will be key factor for accomplishment of the purposes of both users and operators/providers, namely the satisfaction of user’s needs and the augmentation of profit, respectively. In this paper, we focus on an architecture for the management and optimization of spectrum and radio resource utilization in such composite wireless environments, and we analytically present the respective information flow among and from/to the functional entities involved in this architecture. The proposed management architecture can operate in the framework of different business scenarios and is based on related work that has been conducted within the IEEE 1900.4 standard.     

Using the Semantic Web technologies in virtual engineering tools to create extensible interfaces

Ideas and tools developed for the Semantic Web can also be applied to and integrated with engineering tools and software. The ideas upon which the Semantic Web are founded, along with the technologies that are used to implement it, provide a platform on which virtual engineering tools and interfaces can be extended to create a web in which contextual information is readily accessible to engineers. When the Semantic Web and virtual engineering methods are fully realized, computer hardware and networking capabilities will work to provide information and tools to access information meaningfully. The question that must be answered today is: how will information be integrated in a manner that will allow commercial and proprietary software tools to remain separate while also being integrated so that the end user can control and query these tools with little to no knowledge of the tools’ implementation or inner-working details? The answer to this question will depend largely on the ability to implement open interfaces and schemas that can evolve over time as well as open source toolkits that enable development teams to collaborate at a high level. This paper discusses potential applications of the Semantic Web to explore these questions. In addition, specific capabilities being developed in VE-Suite are discussed.     

Domain-Specific Languages: What, Why, How

Domain-specific languages (DSLs) are being increasingly used as a realistic approach to address a program family. That is, a set of programs that shares enough commonalities to be considered as a whole. These programs may already exist or be expected to be developed. In this situation, in principle, software development can benefit from introducing a DSL in that (1) it offers concise and specific notations to express a member of the program family, and (2) it enables the development of safe code thanks to its restricted semantics and/or requirements for additional information.The Compose group has developed DSLs for various domains such as device drivers, active networking, and process scheduling, and built some experience in designing and implementing DSLs. In this talk we will report on the outcomes of this line of work. In particular, we will attempt to provide a practical definition of a DSL, and give the conditions to make this approach successful. We will discuss actual benefits of the DSL approach. Finally, we will outline a methodology to design and implement a DSL.     

Engineering as a co-operative inquiry: A framework

This paper has grown out of my specific dissatisfaction with a view of the world centred on technology, rather than on the people who will use that technology. I have therefore looked for a framework which makes a definite shift of focus towards users, but allowing existing techniques wherever these are helpful. The paper presents a new framework in which requirements engineering is treated as a co-operative inquiry (C1), a general method for reaching shared understanding within a group. The treatment leads to a division of the requirements engineering life cycle into four cycles of co-operation between users and developers. With each cycle, a model (which may be quite conventional) is developed. The approach is compared with existing methods, and some predictions are made about how it may perform.