Activity Relations: A Dataflow Approach to Workflow Design

A key step in workflow design is to determine the activity sequences, which are often driven by the dataflow constraints in a business process. Therefore, the literature has suggested that workflow design can start with dataflow analysis. However, no formalism exists for deriving activity sequences from a set of identified activities and their input and output data. In this paper, we formalize the problem of workflow design on the basis of dataflow analysis. We tackle the problem by using the concept of “activity relations” as an intermediate step for identifying the possible activity execution sequences from dataflow. We investigate how to derive activity relations from dataflow and discuss their implication in workflow design

Preparation and Properties of In-Situ Devices Using the SALD and SALDVI Techniques

One of the many advantages of Selective Area Laser Deposition (SALD) and Selective Area Laser Deposition Vapor Infiltration (SALDVI) is that they can be used to embed in-situ micro-sensors within macro-components. A single-point SiC/C thermocouple sensor embedded within a SiC macro-component and electrically insulated with silicon nitride layers has been demonstrated. In many applications, multi-point sensors within a single component are needed, e.g., in monitoring the temperature gradient and distribution at different positions. In this paper, multi-point thermocouple devices are demonstrated. The macro-component is a SiC bulk shape made by infiltrating vapor deposited silicon carbide into a silicon carbide powder bed using the SALDVI technique. Multiple SiC/C thermocouples are embedded in-situ in the SiC bulk shape using the SALD technique. The transient and steady state responses ofthe embedded thermocouples are compared to reference thermocouples probing the surfaces of the bulk shape.Mechanical Engineerin

Stereometric Design for Desk-Top SFF Fabrication

Solid Freeform Fabrication (SFF) technologies refer to the fabrication of physical parts directly from computer based solid models described by STL (Stereo Lithography) or VRML (Virtual Reality Modeling Language) files generated by Computer-Aided Design (CAD) systems. Most of the SFF processes produce parts by building them layer by layer using a row by row pattern, though it is possible to build the part using other patterns. The SFF technology represents a challenge to designers who, in addition to making decisions concerning optimum shape and functionality of the entire part, have'to take under consideration several other manufacturing factors. These factors cover a wide range of technical issues such as Computer-Aided Design model generation, part description and model slicing files, laser path files, precision of part design, rendering patterns, manufacturing tolerances, thermal expansion and residual stress phenomena. This paper investigates the effect of rendering patterns on the integrity, material characteristics and mechanical properties of the parts prepared by a desk-top SFF device using diode lasers. Fe - Bronze (Cu - Sn) premixed metal powders were used as the starting material. The particle size was about 100 /lm to 200 /lm. Density, tensile strength and microstructure of the parts prepared using different rendering patterns were characterized. The results were analyzed to seek optimal rendering patterns. It was noticed that the samples were strong along the laser scanning direction, while they were weak perpendicular to the scanning direction. These results suggest that the laser scanning patterns should be designed to minimize the warping and maximize the strength of the part in the direction depending on the part's function.Mechanical Engineerin

The role of ATP binding cassette A3 (ABCA3) in health and disease using pluripotent stem cell-derived type II alveolar epithelial cells

The most common causes of childhood interstitial lung disease (chILD) are autosomal recessive mutations in the gene encoding ATP Binding Cassette A3 (ABCA3) protein, a lamellar body (LB) associated lipid transporter exclusively expressed within the alveolar epithelial type II cells (AEC2s) in the lung. Instability of primary AEC2s in culture has prevented studies of ABCA3 mutations, resulting in limited understanding of disease pathogenesis. To overcome this challenge, we developed AEC2-like cells from human pluripotent stem cells (PSCs) in vitro, allowing study of normal ABCA3 function and perturbations that result from ABCA3 mutations. To develop an AEC2 model that would recapitulate ABCA3 biology, we targeted human PSC lines with a knock-in GFP fusion reporter (ABCA3:GFP). Differentiations of PSCs into AEC2s (iAEC2s) resulted in exclusive expression of ABCA3:GFP in iAEC2s and intracellular localization to LAMP3+ vesicles, reminiscent of endogenous ABCA3. Moreover, we find these ABCA3:GFP+ iAEC2s express LBs, process surfactant proteins, and secret surfactant lipids, indicative of preserved ABCA3 function. To study the effects of ABCA3 mutations using our model, we generated two sets of PSC reporter lines: 1) two patient-derived iPSC lines carrying rare homozygous E690K and W308R ABCA3 mutations predicted to affect ABCA3 function or trafficking, respectively, and their two syngeneic gene-corrected lines each targeted with the AEC2-specific knock-in fluorescent reporter SFTPCtdTomato; and 2) three syngeneic ABCA3:GFP knock-in iPSC lines encoding wildtype, E690K, or W308R proteins. Directed differentiation of patient iPSCs into iAEC2s revealed attenuated secretion of surfactant-specific lipids, recapitulating clinical findings of surfactant deficiency. Examination of ABCA3 protein trafficking using the ABCA3:GFP fusion reporter revealed retained E690K and W308R mutant ABCA3 protein processing and trafficking compared to the wildtype protein by confocal microscopy and western blot analyses, however mutant iAEC2s exhibited smaller LBs, indicative of defective ABCA3-dependent lipid transport. Bulk RNA sequencing of mutant and gene-corrected SFTPCtdTomato- or ABCA3:GFP-expressing iAEC2s revealed enrichment of the TNF-NFB pathway in both W308R and E690K mutant iAEC2s, validated by lentiviral reporter assays and secretion of NFB-driven cytokines. Thus, we provide insights into how ABCA3 mutations alter AEC2 physiology and developed a platform to study other genetic AEC2 diseases through our ABCA3:GFP reporter system.2021-05-26T00:00:00

On The Theoretical Foundation for Data Flow Analysis in Workflow Management

In workflow management, the data flow perspective specifies how data are produced and consumed by activities in a workflow. Data flow analysis can detect data flow anomalies occurring in a workflow while its control flow can be syntactically error-free. Currently, most commercial workflow management systems do not provide the tools for data flow analysis at design time. We have previously proposed a data flow analysis approach and developed the basic concepts and the essential algorithms. As another step forward, this paper examines the issues of data flow anomalies and their verification from a theoretical point of view and validates the correctness of the proposed approach

Design practice for blue green infrastructure in the context of urban resilience

This paper presents four projects where design practice is applied to address the challenges of engaging communities in the maintenance of Blue-Green Infrastructure (BGI). The design projects were initiated by the Royal College of Art in partnership with Enfield council, UK. The aim was to develop service propositions that encourage shared ownership of Broomfield Park between local communities and the council. These projects demonstrate the relevance of design practice in developing urban resilience through BGI. When considering BGI as a ‘wicked problem’, design practice demonstrations its potential in fundamentally transforming the traditional way in which public services are designed and implemented

Future states: design and science for sustainability

In 2017 CERN IdeaSquare collaborated with the Royal College of Art, London to explore how an interdisciplinary approach to innovation that combines science, technology, design and business might address the global sustainability challenges as embodied in the UN’s Sustainable Development Goals 2030. This collaboration examined how an interdisciplinary design led model of innovation that fuses design thinking with scientific discovery, could enable the innovative and potentially disruptive technologies from CERN to address the world’s most intractable challenges, and specifically the UN’s Sustainable Development Goals (SDG). In this paper we explore the nature of interdisciplinary innovation, recent trends in its approach, and describe the way this has been applied, through action research, to generate product service systems that address the UN’s SDGs