Shape interpretation with design computing

How information is interpreted has significant impact on how it can be used. This is particularly important in design where information from a wide variety of sources is used in a wide variety of contexts and in a wide variety of ways. This paper is concerned with the information that is created, modified and analysed during design processes, specifically with the information that is represented in shapes. It investigates how design computing seeks to support these processes, and the difficulties that arise when it is necessary to consider alternative interpretations of shape. The aim is to establish the problem of shape interpretation as a general challenge for research in design computing, rather than a difficulty that is to be overcome within specific processes. Shape interpretations are common characteristics of several areas of enquiry in design computing. This paper reviews these, brings an integrated perspective and draws conclusions about how this underlying process can be supported

Supply chain collaboration under uncertainty

In fluctuating economic conditions such as global recession, supply chains operate under changing conditions of uncertainty. The impact of this uncertainty and associated risk might be mitigated by collaboration. This paper proposes a model of supply chain collaboration based on information exchange and decision coordination at both the strategic and tactical levels. However, a collaborative supply chain can be exposed to associated risks such as the failure of individual actors. Governance regimes can facilitate collaboration at the strategic and tactical level and mitigate valid apprehensions about collaboration that the actors may have. Governance can be considered as a critical factor in achieving collaboration. The paper argues for explicit rules to regulate information exchange and decision coordination at the strategic and tactical level. An illustrative case study of an automotive supplier from the electronics industry is used to explain the model

A Method for Improving Overlapping of Testing and Design

Testing is a critical activity in product development. The academic literature provides limited insight about overlapping between upstream testing and downstream design tasks, especially in considering the qualitative differences between activities that are overlapped. In general, the existing literature treats two overlapped sequential activities as similar, and suggests optimal overlapping policies, techniques, and time–cost assessment. However, this case study-based research identifies that the overlapping of upstream testing with downstream design activities has different characteristics than the overlapping of two design activities. This paper first analyzes the characteristics that affect the overlapping of upstream testing and downstream design activities, and then proposes a method to reduce the time of rework in cases where the upstream testing is overlapped with subsequent redesign phases

Improving overlapping between testing and design in engineering product development processes

Testing components, prototypes and products comprise essential, but time consuming activities throughout the product development process particularly for complex iteratively designed products. To reduce product development time, testing and design processes are often overlapped. A key research question is how this overlapping can be planned and managed to minimise risks and costs. The first part of this research study investigates how a case study company plans testing and design processes and how they manage these overlaps. The second part of the study proposes a significant modification to the existing process configuration for design and testing, which explicitly identifies virtual testing, that is an extension to Computer Aided Engineering which mirrors the testing process through product modelling and simulation, as a distinct and significant activity used to (a) enhance and (b) replace some physical tests. The analysis shows how virtual testing can mediate information flows between overlapping (re)design and physical tests. The effects of virtual testing to support overlap of test and (re)design is analysed for the development phases of diesel engine design at a case study company. We assess the costs and risks of overlaps and their amelioration through targeted virtual testing. Finally, using the analysis of the complex interactions between (re)design, physical and virtual testing, and the scope for replacing physical with virtual testing is examined

Prospectus, April 22, 1981

STUGO ELECTIONS NEXT WEDNESDAY; Love Our Prairie Land this week.; We\u27re sorry; Parkland celebrates Arbor Day in style; Classifieds; Register NOW for fall classes; International students plan picnic Saturday; A long Christmas Dinner presented by ISO; Letter to the Editor; Poster boards available for candidates; PC Theatre presents three one-act plays April 23; Get out the kite and frisbee!; Karr speaks at PC on Tropical Ecology ; Rear proves he can play bigtime baseball; It\u27s Arbor Day -- In style!; Cobras recover to split with Kankakee; Cobra softball team 2-0 in CIAC; Hall\u27s 6-3 record wins FF competition; Martin, Ingrum sign tenders; Fast Freddy Contest; PC sports noteshttps://spark.parkland.edu/prospectus_1981/1019/thumbnail.jp

Modus: a Datalog dialect for building container images

Containers help share and deploy software by packaging it with all its dependencies. Tools, like Docker or Kubernetes, spawn containers from images as specified by a build system’s language, such as Dockerfile. A build system takes many parameters to build an image, including OS and application versions. These build parameters can interact: setting one can restrict another. Dockerfile lacks support for reifying and constraining these interactions, thus forcing developers to write a build script per workflow. As a result, developers have resorted to creating ad-hoc solutions such as templates or domain-specific frameworks that harm performance and complicate maintenance because they are verbose and mix languages. To address this problem, we introduce Modus, a Datalog dialect for building container images. Modus' key insight is that container definitions naturally map to proof trees of Horn clauses. In these trees, container configurations correspond to logical facts, build instructions correspond to logic rules, and the build tree is computed as the minimal proof of the Datalog query specifying the target image. Modus relies on Datalog’s expressivity to specify complex workflows with concision and facilitate automatic parallelisation. We evaluated Modus by porting build systems of six popular Docker Hub images to Modus. Modus reduced the code size by 20.1% compared to the used ad-hoc solutions, while imposing a negligible performance overhead, preserving the original image size and image efficiency. We also provide a detailed analysis of porting OpenJDK image build system to Modus

A structurally conserved motif in γ-herpesvirus uracil-DNA glycosylases elicits duplex nucleotide-flipping

Efficient γ-herpesvirus lytic phase replication requires a virally encoded UNG-type uracil-DNA glycosylase as a structural element of the viral replisome. Uniquely, γ-herpesvirus UNGs carry a seven or eight residue insertion of variable sequence in the otherwise highly conserved minor-groove DNA binding loop. In Epstein–Barr Virus [HHV-4] UNG, this motif forms a disc-shaped loop structure of unclear significance. To ascertain the biological role of the loop insertion, we determined the crystal structure of Kaposi’s sarcoma-associated herpesvirus [HHV-8] UNG (kUNG) in its product complex with a uracil-containing dsDNA, as well as two structures of kUNG in its apo state. We find the disc-like conformation is conserved, but only when the kUNG DNA-binding cleft is occupied. Surprisingly, kUNG uses this structure to flip the orphaned partner base of the substrate deoxyuridine out of the DNA duplex while retaining canonical UNG deoxyuridine-flipping and catalysis. The orphan base is stably posed in the DNA major groove which, due to DNA backbone manipulation by kUNG, is more open than in other UNG–dsDNA structures. Mutagenesis suggests a model in which the kUNG loop is pinned outside the DNA-binding cleft until DNA docking promotes rigid structuring of the loop and duplex nucleotide flipping, a novel observation for UNGs

A Millisecond Interferometric Search for Fast Radio Bursts with the Very Large Array

We report on the first millisecond timescale radio interferometric search for the new class of transient known as fast radio bursts (FRBs). We used the Very Large Array (VLA) for a 166-hour, millisecond imaging campaign to detect and precisely localize an FRB. We observed at 1.4 GHz and produced visibilities with 5 ms time resolution over 256 MHz of bandwidth. Dedispersed images were searched for transients with dispersion measures from 0 to 3000 pc/cm3. No transients were detected in observations of high Galactic latitude fields taken from September 2013 though October 2014. Observations of a known pulsar show that images typically had a thermal-noise limited sensitivity of 120 mJy/beam (8 sigma; Stokes I) in 5 ms and could detect and localize transients over a wide field of view. Our nondetection limits the FRB rate to less than 7e4/sky/day (95% confidence) above a fluence limit of 1.2 Jy-ms. Assuming a Euclidean flux distribution, the VLA rate limit is inconsistent with the published rate of Thornton et al. We recalculate previously published rates with a homogeneous consideration of the effects of primary beam attenuation, dispersion, pulse width, and sky brightness. This revises the FRB rate downward and shows that the VLA observations had a roughly 60% chance of detecting a typical FRB and that a 95% confidence constraint would require roughly 500 hours of similar VLA observing. Our survey also limits the repetition rate of an FRB to 2 times less than any known repeating millisecond radio transient.Comment: Submitted to ApJ. 13 pages, 9 figure

DETC2005-85394 PREDICTABILITY OF CHANGE IN ENGINEERING: A COMPLEXITY VIEW

ABSTRACT Design changes can be surprisingly complex. We examine the problems they cause and discuss the problems involved in predicting how changes propagate, based on empirical studies. To assist this analysis we distinguish between (a) a static background of connectivities (b) descriptions of designs, processes, resources and requirements and (c) the dynamics of design tasks acting on descriptions. The background might consist of existing designs and subsystems, or established processes used to create them. The predictability of design change is examined in terms of this model, especially the types and scope of uncertainties and where complexities arise. An industrial example of change propagation is presented in terms of the background (connectivity) -description -action model