Feature Oriented Refinement from Requirements to System Decomposition

Textual user stories capture interactions of users with the system as high-level requirements. However, user stories are typically rather short and backlogs can include many stories. This makes it hard to (a) maintain user stories and backlogs, (b) fully understand the scope of a software project without a detailed analysis of the backlog, and (c) analyse how user stories impact design decisions during sprint planning and implementation. This paper proposes a technique to automatically transform textual user stories into visual use case scenarios in the form of robustness diagrams (a semi-formal scenario-based visualisation of workflows). In addition to creating diagrams for individual stories, the technique allows combining diagrams of multiple stories into one diagram to visualise workflows within sets of stories (e.g., a backlog). Moreover, the technique supports viewpoint-based diagrams, i.e., diagrams that show relationships between actors, domain entities and user interfaces starting from a diagram element (e.g., an actor) selected by the analyst. The technique utilises natural language processing and rule-based transformations. We evaluated the technique with more than 1,400 user stories from 22 backlogs and show that (a) the technique generates syntactically valid robustness diagrams, and (b) the quality of automatically generated robustness diagrams compares to the quality of diagrams created by human experts, but depends on the quality of the textual user stories.

This paper presents a design methodology to modularize integrated fixtures, such as automotive framing systems, to be quickly and cost effectively reconfigured to accommodate a variety of products. Automotive assembly framing systems are used to accurately position and spot-weld the loosely pre-assembled body-in-white (BIW) car body parts. Auto-assembly systems can handle many car body styles; however, the used model-specific BIW framing systems are large, expensive, and the changeover to accommodate different car models takes considerable time. The proposed modularization design methodology aggregates a set of design structure matrices (DSMs) to represent the required changes in the fixtures, the spatial relationships between the used tools and fixtures, and the flow of exchanged information between them. The best granularity level of the modular fixture design architecture is determined using “Cladistics”: a hierarchical biological classification tool. Different tools within the framing system are combined into switchable modules, which allows these integrated systems to be easily reconfigured between different car body styles (product variants). A case study involving four car body styles is used for illustrating the presented design methodology. Results show the validity of the proposed methodology and demonstrate the obtained design of new modular automotive BIW framing system and the methods used for postprocessing and redesigning to improve the framing system's changeability.

The present study addresses integrated manufacturing information systems (IMIS) and highlights importance of realizing ‘adaptability’ and ‘reconfigurability’ characteristics in the system architecture of IMISs, where engineering design for system adaptability is interested. This study develops a matrix-based probabilistic definition for the manufacturing information system (MIS) reconfigurability and proposes modularization of physical architecture of the system as an effective design solution for fulfilling system reconfigurability and adaptability requirements. To modularize the physical architecture, Design Structure Matrix (DSM) method is employed. Moreover, information axiom of Axiomatic Design (AD) theory is also utilized to develop helpful indicators for evaluating the adaptability characteristic for the architecture and support engineering designers to make sound decisions in design for adaptability. To verify the developed methodology, the MIS in a real case (Barez Industrial Group in Iran) is addressed and design of the physical architecture for this system is studied. A new optimally modularized design for the physical architecture of the MIS of interest is finally presented and examined. Results of the indicators reflecting reconfigurability and adaptability of the architecture indicate that the new proposed design of the concerned MIS is highly capable of coping with the rapidly changing manufacturing environment.

The 2000s have been marked by significant change both in the nature of the vehicle and in its design process. The car satisfies an ever-present need. It longitudinally, autonomously and safely carries a reduced number of passengers and goods. In the future, acceptable vehicles must achieve requirements like reliability, safety, drivability, low gas consumption, minimal environmental footprint, low cost... The satisfactory solutions the designers are expected to offer can not be considered as pure mechanical systems. They integrate coupled functional modules that are embodied in multi-physical components (mechanical components, electronic or electrical devices, embebbed software...). Their design requires skills that are new from the automotive design managers’ viewpoint. The issue concerning the identification, evaluation, building and modelling of skill networks opens promising ways for researchers and practitioners. Thus the purpose of this chapter will be to define the concept of skill network and to explain how it can be mapped by using “Design Structure Matrices” (DSMs) (Browning, 2001). This chapter will be illustrated with an example concerning a French automaker’s design office (Bonjour & Micaelli, 2010). It aims at developing vehicle organs. These ones concern the powertrain system and the chassis. Their life cycle exceeds two decades. Thus designing them consists in developing a product family compliant with different platforms, models or generations of vehicles. These organs are mass produced. Since 1997, the mentioned design office of over 5,500 designers has been structured according to the systems engineering principles and processes (ISO 15288). Depending on the project, its technical activity partially or totally covers the Vee cycle. In this chapter, we shall not address the issue of skill network identification, mapping and building from a global viewpoint, but from a local one focused on the intermediate layer of the Vee cycle, namely the design of functional architectures. We therefore describe how the skill networks related to this task are restructured. The remainder of this chapter is structured as follows. Section 2 defines the concept of skill network. It also proposes a conceptual framework including close concepts (job position, profession, core competence...). Section 3 outlines examples of skill networks and the

Evolutionary design assistants for architecture

Evolutionary design assistants for architecture

Architecture design is an extremely important part of complex system design, and it is of far-reaching significance to carry out research on architecture design. Starting from the needs of users, this paper combines the “Z”-shaped mapping structure and hierarchical decomposition mode of the axiom design theory, as well as the design structure matrix method to implement system module division, and specifically analyzes the system architecture design concept generation process.

This paper presents an algorithm of modular identification in product architecture design on the base of information dependency. A design structure matrix (DSM) model is constructed to capture the relationship between members, and it can be transformed for searching better product structure. A coordination cost function is defined to evaluate modular quality. If the cost of every module is same, it is impossible to find out better modules, consequently, an auxiliary estimated function is also proposed. It avoids the limitation of coordination cost function and would be capable of accurately selecting available module. A detail of calculation steps are described and a testing case illustrates the effect of the algorithm. The results also show that the optimal modular partition can be obtained. The method may be applied in product design management for clustering components to prompt quality of product, for ordering design parameters and for building a development team to speed up development process

This paper investigates the dynamics analysis and robust control law design for the proposed schematic design of electric unicycles. The schematic design of the proposed unicycle possesses a supportive seat for the rider and is also equipped with a handling rod for maneuvering, similar to a Segway device. First, this paper conducts an analysis and comparison of the dynamics properties and derivation of the nonlinear governing equation for the unicycle. Next, it emphasizes the development of an input-constrained robust controller design for the proposed configuration of the electric unicycle. The issues investigated in this paper include the dynamics property analysis and comparison, nonlinear dynamics derivation, robust control diagram formulation, controller synthesis regarding linear matrix inequalities (LMIs), and time response simulations and discussions. In this control law design via LMIs, the desired performances of: (1) relative stability or decay rate for command tracking capability; (2) disturbance attenuation for robustness against uncertainty parameters; and (3) an accommodation of control effort constraints under the regulation or command tracking of certain initial state condition are investigated and demonstrated using time response simulations of the controlled unicycle dynamics.

Focused on the image data storage, compression and transmission of mars rover, system design and key hardware/software architecture design are carried out in this paper based on the analysis of function requirements and key design features. Image compression algorithm and transmission protocol are proposed, and the image storage and compression module in Mars rover is designed and implemented. The multi-camera partition parallel image file system based on FPGA（Field Programmable Gate Array）is realized. The adaptive first 1 run length coding algorithm for image compression based on DSP is realized on this module. Finally the function of multi-camera image data storage and management, flexible control of image compression ratio, quality progressive transmission, coding of region of interest, anti-error code diffusion and image thumbnail downward transmission are realized in the engineering development, meeting the reliable, efficient and flexible application requirements of China’s first Mars exploration mission.

Medical imaging enables researchers and practitioner to uncover the characteristics of diseases (e.g., human cancer) in great detail. However, the sheer size of resulting imaging data and the high dimension of derived features become a major challenge in data analysis, diagnosis, and knowledge discovery. We present a novel visual analytics system, named iVAR, targeted at observing the comprehensive quantification of tumor phenotypes by effectively exploring a large number of quantitative image features. Our system is comprised of multiple linked views combining visualization of three-dimensional volumes and tumors reconstructed by computed tomography (CT) images, and a radiomic analysis of high-dimensional features quantifying tumor image intensity, shape and texture, and three non-image clinical features. Thus, it offers insights into the overall distribution of quantitative imaging features and also enables detailed analysis of the relationship between features. We demonstrate our system through use case scenarios on a real-world large-scale CT dataset with lung cancer.

BackgroundX‐chromosome short tandem repeats (X‐STRs) with unique sex‐linkage inheritance models play a complementary role in forensic science. Guizhou is a multiethnic province located in southwest China and some genetic evidence focusing on X‐STRs for various minorities was reported. However, population data of Guizhou Tujia are scarce.MethodsA total of 507 Guizhou Tujia individuals were profiled using the AGCU X‐19 STR kit. Allele frequencies and forensic parameters were calculated. Additionally, population genetic relationships between Guizhou Tujia and other 19 populations were explored.ResultsA total of 257 alleles with the allele frequencies ranged from 0.0013 to 0.6098 were found. The combined power of discrimination in males and females and mean exclusion chances in all case scenarios were all greater than 0.99999. Population comparisons showed Guizhou Tujia had a homogeneity with all Han populations from different administrative regions, and other ethnic populations residing in Guizhou, while had obviously genetic heterogeneity with the Altaic family populations except Xibe.ConclusionNineteen X‐STRs can afford a reliable and informative database of Guizhou Tujia population for human identification and paternity testing, especially in complex biological relations. The genetic relationships of Chinese are significantly influenced by the geographic position and ethnolinguistic origin.

In this era of ubiquitous computing, coupled with the emergence of big data and internet of things, there have been constant changes in every aspect of cloud data center communications - its network connectivity, data storage, data transfer, and architectural design. As a result of this, the amount of data transferable, and the frequency of data transfer have tremendously increased; causing device failures and traffic congestions. To cope with these changes so that performance can be sustained amidst device failures and traffic congestion, the design of fault tolerant cloud data center is important. A fault tolerant cloud data center network should be able to provide alternative paths from source to destination during failures so that there will not be abrupt fall in performance. But still with the ongoing researches in this regard, there has not been a robust cloud data center design that can boast of being suitable for alleviating the poor fault tolerance of cloud data center. In this paper, we proposed the improved versions of fat-tree interconnection hybrid designs derived from the structure called Z-fat tree; to address the issues of fault tolerance. Then, we compared these designs with single fat tree architecture with the same amount of resources for client server communication pattern such as Email application in a cloud data center. The simulation results obtained based on failed switches and links, show that our proposed hybrid designs outperformed the single fat tree design as the inter arrival time of the packets reduces.

Robust Controller Design for Feedback Architectures with Signal Shapers

Hot-wire anemometry has been routinely employed for laboratory measurements of turbulence for decades. This thesis presents a hot-wire anemometer suitable for use with the Boundary Layer Data System (BLDS). BLDS provides a unique platform for in- flight measurements because of its small, self-contained, robust design and flexible architecture. Addition of a hot-wire anemometer would provide BLDS with a sensor that could directly measure flow velocity fluctuations caused by turbulence. Hot-wires are commonly operated in constant-temperature mode for high frequency response, but require a carefully tuned bridge. The constant-voltage anemometer (CVA) uses a simple op-amp circuit to improve frequency response over constant-current operation. Due to its balance between ease of operation and performance, a CVA system built for this project was tested with a 3.8 micron diameter, platinum-coated tungsten probe. The CVA was calibrated in a steady jet and a power-law curve fit accurately represented the calibration data. The CVA successfully measured velocity fluctuations in a turbulent jet, as well as in laminar and tripped turbulent boundary layers over a flat plate in a 110 MPH wind tunnel. CVA frequency response was investigated using a thermal/electrical model, controlled oscillation in a steady flow, and with a square wave test; these three methods showed agreement. The CVA is selected for integration with BLDS.