A language for behavioural modelling of architectural patterns

The complexity of interactions governing the coordination of loosely-coupled services, which forms the core of current software, brought behavioural issues up to the front of architectural concerns. This paper takes such a challenge seriously by lifting typical behaviour modelling techniques to the specification of both types and instances of architectural patterns in which the later ones are connected by ports that behave according to a water flow metaphor. A specific language is introduced for this purpose as well as a translator to mCRL2 so that the simulation and analysis techniques available in the corresponding toolset can be used to reason about (the behavioural layer of) software architectures. The approach is illustrated in a few examples(undefined

Verifying bigraphical models of architectural reconfigurations

ARCHERY is an architectural description language for modelling and reasoning about distributed, heterogeneous and dynamically reconfigurable systems. This paper proposes a structural semantics for ARCHERY, and a method for deriving labelled transition systems (LTS) in which states and transitions represent configurations and reconfiguration operations, respectively. Architectures are modelled by bigraphs and their dynamics by parametric reaction rules. The resulting LTSs can be regarded as Kripke frames, appropriate for verifying reconfiguration constraints over architectural patterns expressed in a modal logic. The derivation method proposed here applies Leifer's approach twice, and combines the results of each application to obtain a label representing a reconfiguration operation and its actual parameters. Labels obtained in this way are minimal and yield LTSs in which bisimulation is a congruence.FC

Cost-effective, near-term deployment of carbon capture and storage from biorefineries in the United States

Abstract: Capture and permanent sequestration of biogenic CO2 emissions play a pivotal role in stringent climate change mitigation. Bioenergy with carbon capture and sequestration (BECCS) technologies, in particular, can remove atmospheric CO2 emissions while producing valuable energy products such as fuels, electricity, and gaseous hydrocarbons. Yet, most near-term assessments of climate change mitigation opportunities assume BECCS is either too costly or commercially unavailable. In contrast, biogenic CO2 capture and sequestration from industrial fermentation is already deployed at commercial scale, including several corn ethanol facilities in the United States. Such capture opportunities target pure streams of biogenic CO2 from existing biofuel infrastructure, resulting in a low cost of capture and sequestration. Moreover, existing and proposed policies in the United States, including California’s Low Carbon Fuel Standard (LCFS) and the 2016 Carbon Capture Utilization and Storage Act (S.3179, the CCUS Act), could provide sufficient financial incentive for industry-wide deployment of CCS for saline aquifers. Here, we study the abatement potential and costs of biogenic CO2 capture and sequestration from biorefineries in the United States using process engineering, spatial optimization, and lifecycle assessment. We minimize the total cost of capture, compression, transportation, and sequestration, building from existing spatial pipeline optimization models [1]. We consider two options for CO2 transport: pipelines, and trucking, which recent work has shown is cost-effective at low CO2 volumes [2]. Preliminary results identify ~44 Mt of biogenic CO2 emitted annually from 217 facilities, most of which can be captured for under $30/tCO2. We also find strong evidence for economies of scale in pipeline transportation. Recent financial incentives under California’s LCFS (~$75-150/tCO2 abated) and proposed in the U.S Senate ($50/tCO2 stored in saline aquifers) suggest a substantial near-term opportunity to permanently sequester biogenic CO2, given proper policy incentives. This opportunity can catalyze the growth of carbon capture, transport, utilization, and sequestration across the U.S. and improve the lifecycle impacts of conventional ethanol. When complete, we expect to produce the following results: Spatially-optimized infrastructure design and supply curves for biogenic CO2 capture, transport, and sequestration in the United States, for both pipeline and truck transport Lifecycle carbon intensity impacts for transportation fuels, evaluated under CA-GREET Cost-optimal deployment levels under multiple CA LCFS and CCUS Act price scenarios References: [1] N. Johnson, J. Ogden, Detailed spatial modeling of carbon capture and storage (CCS) infrastructure deployment in the southwestern United States, Energy Procedia, 4 (2011). [2] P. Psarras, P. Bains, P. Charoensawadpong, M. Carringon, S. Comello, S. Reichelstein, J. Wilcox, A Pathway Towards Reducing CO2 Emissions from the Industrial Sector (In Press)

Interactively modelling land profitability to estimate European agricultural and forest land use under future scenarios of climate, socio-economics and adaptation

Studies of climate change impacts on agricultural land use generally consider sets of climates combined with fixed socio-economic scenarios, making it impossible to compare the impact of specific factors within these scenario sets. Analysis of the impact of specific scenario factors is extremely difficult due to prohibitively long run-times of the complex models. This study produces and combines metamodels of crop and forest yields and farm profit, derived from previously developed very complex models, to enable prediction of European land use under any set of climate and socio-economic data. Land use is predicted based on the profitability of the alternatives on every soil within every 10' grid across the EU. A clustering procedure reduces 23,871 grids with 20+ soils per grid to 6,714 clusters of common soil and climate. Combined these reduce runtime 100 thousand-fold. Profit thresholds define land as intensive agriculture (arable or grassland), extensive agriculture or managed forest, or finally unmanaged forest or abandoned land. The demand for food as a function of population, imports, food preferences and bioenergy, is a production constraint, as is irrigation water available. An iteration adjusts prices to meet these constraints. A range of measures are derived at 10' grid-level such as diversity as well as overall EU production. There are many ways to utilise this ability to do rapidWhat-If analysis of both impact and adaptations. The paper illustrates using two of the 5 different GCMs (CSMK3, HADGEM with contrasting precipitation and temperature) and two of the 4 different socio-economic scenarios ("We are the world", "Should I stay or should I go" which have contrasting demands for land), exploring these using two of the 13 scenario parameters (crop breeding for yield and population) . In the first scenario, population can be increased by a large amount showing that food security is far from vulnerable. In the second scenario increasing crop yield shows that it improves the food security problem

Analysing tactics in architectural patterns

We present an approach to analyse the application of tactics in architectural patterns. We define and illustrate the approach by resorting to Archery, a language for specifying, analysing and verifying architectural patterns. The approach consists of characterising the design principles of an architectural pattern as constraints, expressed in the language, and then, establishing a refinement relation based on their satisfaction. The application of tactics preserving refinement preserves the original design principles expressed themselves as constraints for the architectural pattern. The paper’s focus on fault-tolerance tactics, and identifies a set of requirements for a semantic framework characterising them. Model transformations to represent their application are discussed and illustrated through two case studies.FC

Major requirements for building Smart Homes in Smart Cities based on Internet of Things technologies

The recent boom in the Internet of Things (IoT) will turn Smart Cities and Smart Homes (SH) from hype to reality. SH is the major building block for Smart Cities and have long been a dream for decades, hobbyists in the late 1970s made Home Automation (HA) possible when personal computers started invading home spaces. While SH can share most of the IoT technologies, there are unique characteristics that make SH special. From the result of a recent research survey on SH and IoT technologies, this paper defines the major requirements for building SH. Seven unique requirement recommendations are defined and classified according to the specific quality of the SH building blocks

Environmental Engineering Division Panel Discussion: Exploring Career Paths in Academia - Learn, Network, and Thrive

This Environmental Engineering Division Panel Will Provide an Opportunity to Learn from and Connect with Faculty and Leaders in the Environmental Engineering Field. Drawing on Expertise from the Premier Academic Organizations Associated with Environmental Engineering: The American Academy of Environmental Engineers and Scientists (AAEES), the Association of Environmental Engineering and Science Professors (AEESP), and the American Society of Civil Engineers (ASCE). the Panel is for All Graduate Students, Post-Docs and Early Career Faculty Who Are Interested in Receiving Advice and Networking to Advance their Careers in Environmental Engineering. the Panel Will Focus on Sharing the Experiences and Best Practices for Pursuing Different Academic Paths, Including Securing a Faculty Appointment and Thriving as a New Faculty Member. We Invite All Students and Faculty in Environmental Engineering to Join Us for This Exciting Panel. the Suggested Layout of the Panel Session Is: • 5-Minute Introduction of Panel Topic and Panelists • overview of Each Panelist\u27s Career Journey (5 Minutes Each) • Quick Survey of the Room to Understand Where the Audience is in their Career and Where their Interests Lie. • Whole Group Q&A Session to Engage Audience and Panelists

Changes in and the mediating role of physical activity in relation to active school transport, fitness and adiposity among Spanish youth: the UP&DOWN longitudinal study

Background Longitudinal changes in child and adolescent active school transport (AST), and the mediating role of different intensities of daily physical activity (PA) levels in relation to AST and physical fitness and adiposity indicators is unclear. This study aimed to: 1) describe longitudinal changes in AST, light PA (LPA), moderate- to vigorous-intensity PA (MVPA), physical fitness and adiposity indicators over three time-points; and 2) investigate the mediating role of LPA and MVPA levels on associations between AST and physical fitness and adiposity indicators over three time-points among children and adolescents. Methods This longitudinal study comprised 1646 Spanish children and adolescents (48.8% girls, mean age 12.5 years +/- 2.5) at baseline, recruited from schools in Cadiz and Madrid. Mode of commuting to school was self-reported at baseline (T0, 2011-12), 1-year (T1) and 2-year follow-up (T2). PA was assessed using accelerometers. Handgrip strength, standing long jump and cardiorespiratory fitness (CRF) assessed physical fitness. Height, weight, body mass index, waist circumference, and triceps and subscapular skinfold thickness were measured. Multilevel linear regression analyses assessed changes in AST, PA levels, physical fitness and adiposity indicators over three time-points (T0-T1-T2). Additionally, longitudinal path analysis (n = 453; mean age [years] 12.6 +/- 2.4) was used to test the mediating effects of LPA and MVPA levels on the association between AST and physical fitness and adiposity indicators. Results Multilevel analyses observed decreases in LPA between T0-T1 (beta = - 11.27; p < 0.001) and T0-T2 (beta = - 16.27; p < 0.001) and decreases in MVPA between T0-T2 (beta = - 4.51; p = 0.011). Moreover, changes over time showed increases in handgrip between T0-T1 (beta = 0.78; p = 0.028) and T0-T2 (beta = 0.81; p = 0.046). Path analyses showed that AST was directly positively associated with MVPA at T1 (all, beta approximate to 0.33; p < 0.001). MVPA at T1 mediated associations between AST and CRF at T2 (beta = 0.20; p = 0.040), but not the other outcomes. LPA did not mediate any associations. Conclusions Results from longitudinal path analysis suggest that participation in more AST may help attenuate declines in MVPA that typically occur with age and improve CRF. Therefore, we encourage health authorities to promote AST, as a way to increase MVPA levels and CRF among youth

Effect of scandium triflate on the RAFT copolymerization of methyl acrylate and vinyl acetate controlled by an acid/base “switchable” chain transfer agent

Modulation of the activity of an acid/base switchable dithiocarbamate RAFT agent, cyanomethyl (4-fluorophenyl)(pyridin-4-yl)carbamodithioate, with the Lewis acid scandium triflate (Sc(OTf)3) was investigated to examine the ability to deliver improved control over RAFT copolymerizations involving both more-activated and less-activated monomers—specifically the copolymerization of methyl acrylate (MA) and vinyl acetate (VAc). The introduction of either 0.5 or 1 mol equiv of Sc(OTf)3, with respect to RAFT agent, into a RAFT copolymerization of MA and VAc provides substantially improved control resulting in significantly reduced molar mass dispersities (Đ) (∼1.1–1.3) than achieved in its absence (Đ ∼ 1.3–1.4). Furthermore, similar introduction of Sc(OTf)3 into MA homopolymerization mediated by the same RAFT agent also delivered polymers of very low Đ (∼1.15). Sc(OTf)3 was also found to lower the rate of polymerization and alter the copolymerization reactivity ratios for MA and VAc. Increasing the Lewis acid concentration provides enhanced incorporation of the less active monomer, VAc, into the copolymers ([Sc(OTf)3]/[RAFT] = 0, rMA = 4.04, rVAc = 0.032; [Sc(OTf)3]/[RAFT] = 0.5, rMA = 3.08, rVAc = 0.17; [Sc(OTf)3]/[RAFT] = 1, rMA = 2.68, rVAc = 0.62). Carbon nuclear magnetic resonance (13C NMR) and differential scanning calorimetry (DSC) analysis of preparative samples confirm the enhanced VAc incorporation with increased levels of Sc(OTf)3. Importantly the inclusion of Sc(OTf)3 does not deleteriously affect the thiocarbonylthio end-groups of the RAFT polymers, with high end-group fidelity being observed in all copolymerizations