Island Configurations Research Articles

Synchronization-oriented reconfiguration of FPAI under graduation intelligent manufacturing system in the COVID-19 pandemic and beyond

Companies with manufacturing systems that are more responsive and resilient will be able to survive or even gain market shares in the face of the unpredicted variable of an outbreak similar to the COVID-19 pandemic. Motivated by an industrial company restructuring its manufacturing system with the layout of fixed-position assembly islands (FPAI) during the COVID-19 pandemic, this paper introduces the synchronization-oriented reconfiguration of FPAI under Graduation Intelligent Manufacturing System (GiMS). Inspired by the graduation ceremony, a novel manufacturing mode-Graduation Manufacturing System (GMS) with ticket-based reconfigurable structures, is designed for organizing production operations with simplicity and resilience for the layout of FPAI. The IIoT and digital twin-enabled GiMS is developed for transforming real-time visibility in operations to support the reconfiguration of the manufacturing system. A synchronization-oriented reconfiguration mechanism is proposed to achieve the synchronous interaction among changing customer demand, island configuration, and production activities allocation rapidly and cost-effectively. Cloud services integrating the proposed reconfiguration mechanism are developed for managers and onsite operators for supporting the successful reconfiguration implementation with enhanced operational visibility. Through the case study of an industrial company, the effectiveness of the proposed concept and approach is verified.

Does explicit instruction affect L2 linguistic competence? An examination with L2 acquisition of English inverse scope

This article investigates whether explicit instruction can affect second language (L2) competence in the domain of English quantifier scope. An intervention study was conducted with L1-Mandarin L2-English learners in order to examine (1) whether these learners can learn inverse scope for the structure on which they are instructed (double-quantifier configuration: A dog scared every man; quantifier-negation configuration: Every sheep did not jump over the fence); (2) whether they can correctly generalize availability of inverse scope from the configuration on which they are instructed to one on which they are not instructed; and (3) whether learners overgeneralize inverse scope to a superficially similar configuration that does not allow inverse scope. Following Schwartz (1993), generalization is taken to be a hallmark of true acquisition (= changes to linguistic competence) as opposed to learning. The results show that learners successfully learn inverse scope for the configuration on which they are instructed, but do not generalize availability of inverse scope to the other configuration. Moreover, learners instructed on double-quantifier configurations overgeneralize availability of inverse scope to island configurations such as There is one dog which scared every man. The findings indicate that in this domain, explicit instruction does not affect linguistic competence.

Analiza poprawności montażu paneli słonecznych dla systemów IoT

The article considers the impact of the building and roof structures on the efficiency of obtaining electricity from photovoltaic panels. Meteorological and astronomical data were also taken into account. The result of the analysis on the basis of installations in single-family houses was used as a base for installations in IoT systems. In addition, mechanical installation of photovoltaic panels for measuring systems in island configuration will be considered. The article was written as a part of Statutory Work 1115538-173.

Exploring Multiple Analog Placements With Partial-Monotonic Current Paths and Symmetry Constraints Using PCP-SP

Modern analog placement techniques require consideration of current path and symmetry constraints. The symmetry pairs can be efficiently packed using the symmetry island configurations, but not all these configurations result in minimum gate interconnection, which can impact the overall circuit routing and performance. This article proposes the first work that reformulates this problem considering all of them together in the form of parallel current path (PCP) constraints. PCP constraints, in addition to monotonic current paths, also consider partial-monotonic current paths to generate a more compact placement. We use a novel two-step approach to detect symmetry-feasible sequence-pairs (SFSPs) without doing placement construction by using representative sequence-pair (RSP). Then a placement algorithm satisfying these constraints is formulated to reduce a vast search space via efficient sequence pair manipulation. The experimental results show that this formulation and algorithm can generate multiple placement solutions that satisfy all the constraints in a more tightly packed configuration, resulting in smaller wirelength, reduced parasitics, and thus better post-layout performance.

Planning approach of urban blue-green space based on local climate optimization: A review

Local climatic problems are widespread in cities under high-density and high-intensity construction mode in China, including heat island effect, poor ventilation, and frequent haze wea-ther. Urban blue-green space is vital for mitigating wind and heat, and for improving air quality, and therefore has become a hotspot of urban planning and design research dealing with climatic problems. Here, we reviewed the climate effects of urban blue-green space. In particular, we summarized the research progress of planning approaches to cool island landscape features optimization, cooling island configuration, ventilation corridor network connection and ventilation corridor interface control based on the levels of planning layout and network construction. We proposed a basic framework of urban blue-green space planning optimizing local climate by combining intelligent simulation platform, evaluation index system, planning and design guide, and guarantee mechanism for implement, aiming to provide key evidence for urban climate adaption and design.

The First Dorsal Metacarpal Artery Free Flap for Salvage of Nasal Reconstructions.

The first dorsal metacarpal artery free flap is widely known for its use as a pedicled flap in thumb and hand reconstruction; however, its potential for use as a free flap is less well known. We previously described successful use of the first dorsal metacarpal artery free flap for salvage of a subtotal nasal reconstruction. In this retrospective study, we have expanded our experience to 7 consecutive cases in which a FDMFF was utilized to salvage a nasal reconstruction. Single island flaps were used in 6 of 7 cases, in one case a double island configuration was utilized. Sites restored included the columella (5 patients), membranous septum (1 patient), and nasal sidewall (1 patient). Vascular repairs were to the angular artery and vein (2 patients) or the vascular pedicle of a prior free flap (5 patients). There were no flap failures or major complications. The dorsal hand donor sites were uniformly closed using full-thickness skin grafts. All of the salvage nasal reconstructions were brought to a successful completion. Donor site morbidity was minimal with no compromise in hand function noted. Owing to its thinness, consistent anatomy, ease of harvest, and minimal donor site morbidity, the FDMFF has proved to be a very useful flap for restoration of small, but critical, nasal defects arising during the course of nasal reconstruction.

Tidal sand ridges on the shelf: A numerical study of their natural morphodynamic evolution and response to interventions

Tidal sand ridges are large-scale bottom features that occur on continental shelves with strong tidal currents and abundance of sand. These ridges have longshore spacings of several kilometres, heights of tens of metres, they evolve on centennial time scales and their crests are cyclonically rotated with respect to the direction of the dominant tidal currents. The coupled Delft3D-SWAN numerical model is used to study the natural morphodynamic evolution of tidal sand ridges and their response to interventions (sand extraction and construction of islands) in a setting that resembles the Belgian shelf. New aspects in this study are that a sophisticated wave model (SWAN), a shelf with a sloping bottom and state-of-the-art formulations for sediment transport (including suspended load) are considered.Starting from an initially flat bed, model results show that sand ridges develop on the shelf that have similar characteristics as those of observed tidal sand ridges. Results further show that ridges recover after sand extraction, i.e., the original sand volume of the ridge crests is recovered on decadal time scales. Deepening of the troughs provides sand for this recovery. The recovery of the ridges is weaker when pits are located further offshore and/or are deeper. Ridges recover faster when waves are included. If a sand pit is too deep (>4 m), the ridge loses sand in the first tens of years prior to its recovery on longer time scales. This initial sand loss seems to agree with the observed loss of sand volume from a tidal sand ridge on the Belgium shelf (Kwinte Bank), which has been subject to intense extractions.Model results further show that islands lose sand on decadal time scales until they eventually disappear. This sand loss is deposited on the crests and in the troughs. The presence of islands causes the surrounding ridges to break into smaller ridges that have smaller orientation angles than those of the natural case. Using different island configurations (location, geometry and number of islands, longshore distance between islands) does not lead to qualitative changes of the model results.

Wh-Movement, Islands, and Resumption in L1 and L2 Spanish: Is (Un)Grammaticality the Relevant Property?

This study reflects on the meaning of the results of a self-paced grammaticality judgment task that tested island configurations (with gaps and resumptive pronouns) in L1 and L2 speakers of Spanish. Results indicated that resumptive pronouns do not rescue extractions from islands, as traditionally assumed in grammatical theory, and propose that islands are essentially an interpretative or processing matter, and not only a grammatical one, as in Kluender (1998). This study further challenges the L2 studies that proposed that L2 learners are fundamentally different from native speakers because they usually fail to reject island configurations, and shows that L2 learners are sensitive to the same processing and interpretative mechanisms that native speakers employ to parse island configurations. Generally speaking, this study proposes that apparent purely syntactic restrictions such as extractions from islands might not depend on their grammatical formation, but on other relevant factors such as plausibility, embedding, and processability, which together with grammatical well-formedness configure a more holistic and useful notion of linguistic acceptability.

The charge transfer of intercalated Li atoms around islands on Li-halide (F, Br, Cl) surface of SEIs: A first principles calculation

The solid electrolyte interface (SEI) not only play the role of surface protective film for lithium metal anodes in lithium-sulfur batteries but also use to suppress the growth of lithium dendrites during the charging process. The relationship between the morphology of the SEI and the deposition behavior of lithium atoms determines the effect of homogenization of the dendrites. The Li-halide (LiF, LiCl, and LiBr) solid electrolyte interface is comparatively investigates by comprehensive first-principles calculations on Li metal anodes. Surface adsorption, surface diffusion, and charge transfer of Li atoms during the deposition process on the Li-halide SEIs with aggregated Li–Ha2Li2 island configurations is systematically calculates to achieve the orientation of Li atoms from deposition. However, the Li atom has high migration energy regardless of the uniformity of the surface of LiF-SEI, which has high stability making the charge transfer of Li atoms less affected by the subneighbor and subsurface Ha atoms. The Li atom deposition behavior makes the charge transfer and lithium halide (LiHa) SEI potential tend to be evenly distributed, which in turn leads to uniform deposition of Li atoms.

The contribution of different habitat types to species diversity of Baltic uplift islands

Islands are vulnerable ecosystems worldwide, increasingly exposed to human pressure, global climate change and invasive species. Thus, understanding island species diversity is key for nature conservation. Recent studies on insular plant communities indicated that habitat-specific species composition and richness might largely affect diversity patterns observed at the island scale. In consequence, habitat-based approaches are needed to (i) estimate how environmental changes at the habitat scale may affect island diversity, and to (ii) estimate the contribution of different patches of the same habitat to island diversity with respect to habitat-specific environmental constraints.In the present study, we tested these habitat-to-island diversity relationships for shoreline habitats (brackish reeds, salt marsh, rocky shore, tall herbs) and island interior habitats (rocks, semi-natural grassland, pioneer forest, coniferous forest, mixed forest) using 108 islands of three Baltic archipelagos in Sweden. These islands differed in terms of island-scale variables describing effects of island configuration and distance, and habitat-scale variables representing the effects of habitat area, abiotic environment and land-use.The studied habitats differed in their contribution to island species diversity, called habitat specificity. Shoreline habitats shared many common specialist species adapted to extreme conditions like sea salt or bird grazing, while habitats of the island interior harbored mainly species adapted to the specific conditions of a single habitat. We found high variability in habitat specificity as a consequence of habitat-specific environmental factors. Variability was highest for grasslands, where it was related to abandonment and soil fertility, stressing the importance of grassland management for maintaining island biodiversity. Habitats with high habitat specificity through either high species richness or many habitat-specific specialists should be the primary targets for biodiversity management.

Topology Identification in Distribution Systems Using Line Current Sensors: An MILP Approach

This study is motivated by the recent advancements in developing non-contact line sensor technologies that come at a low cost, but have limited measurement capabilities. While they are intended to measure current, they cannot measure voltage and power. This poses a challenge to certain distribution system applications, such as topology identification (TI), because they commonly use voltage and power measurements. To address this open problem, a new TI algorithm is proposed based on measurements from a few line current sensors, together with available pseudo-measurements for nodal power injections. A TI problem formulation is first developed in the form of a mixed integer nonlinear program (MINLP). Several reformulation steps are then adopted to tackle the nonlinearities to express the TI problem in the form of a mixed integer linear program (MILP). The proposed method is able to identify all possible topologies, including radial, loop, and island configurations, which extends the application of TI to identify switch malfunctions and to detect outages. In addition, recommendations are made with respect to the number and location of the line current sensors to ensure performance accuracy of the TI method. A novel multi-period TI algorithm is also proposed to use multiple measurement snapshots to improve the TI accuracy and robustness against errors in pseudo-measurements. The effectiveness of the proposed TI algorithms is examined on the IEEE 33-bus test case as well as a test case based on a real-world feeder in Riverside, CA.

Sediment Transport Processes during Barrier Island Inundation under Variations in Cross-Shore Geometry and Hydrodynamic Forcing

Inundation of barrier islands can cause severe morphological changes, from the break-up of islands to sediment accretion. The response will depend on island geometry and hydrodynamic forcing. To explore this dependence, the non-hydrostatic wave model SWASH was used to investigate the relative importance of bedload transport processes, such as transport by mean flow, short- (0.05–1 Hz) and infragravity (0.005–0.05 Hz) waves during barrier island inundation for different island configurations and hydrodynamic conditions. The boundary conditions for the model are based on field observations on a Dutch barrier island. Model results indicate that waves dominate the sediment transport processes from outer surfzone until landwards of the island crest, either by transporting sediment directly or by providing sediment stirring for the mean flow transport. Transport by short waves was continuously landwards directed, while infragravity wave and mean flow transport was seaward or landward directed. Landward of the crest, sediment transport was mostly dominated by the mean flow. It was forced by the water level gradient, which determined the mean flow transport direction and magnitude in the inner surfzone and on the island top. Simulations suggest that short wave and mean flow transport are generally larger on steeper slopes, since wave energy dissipation is less and mean flow velocities are higher. The slope of the island top and the width of the island foremost affect the mean flow transport, while variations in inundation depth will additionally affect transport by short-wave acceleration skewness.

Experimental study of long wave dynamics in the presence of two offshore islands

Following the 2010 Mentawai tsunami, observations in Sumatra by Hill et al. (J Geophys Res Solid Earth, 2012. https://doi.org/10.1029/2012jb009159 ) noted enhanced tsunami runup in coastal areas behind island chains. Many local communities in the region, however, falsely believed that islands provide shelter against tsunami waves. The present study aims to capture when and how island chains are amplifiers of wave energy in the coastal areas they shadow, which is often where coastal communities thrive. Physical modeling was carried out in the Directional Wave Basin at the Oregon State University O.H. Hinsdale Wave Research Laboratory. The experiment included four island configurations and three different waveforms a: solitary wave, error function wave and a leading depression N-wave. Results suggest that island chains can act as wave amplifiers, indicating potential amplification in both shoreline runup and current velocity. The amplification is, however, not consistent with every waveform. Also, in some cases, the impact of the offshore islands led to a reduction in coastal impacts. This result suggests that the offshore waveform plays an important role in the wave dynamics between the islands and on the wave uprush directly behind the islands.

MHD Stability and Energy Principle for Two-Dimensional Equilibria without Assumption of Nested Magnetic Surfaces

Abandoning the assumption of nested magnetic surfaces in tokamak plasma expands the field of research and opens up new approaches for both theoretical and experimental plasma physics. The computer code KINX for calculations of the ideal MHD stability was developed for studies of doublet plasmas with two magnetic axes and using block-structured grids in each subdomain with nested magnetic surfaces. Then, the MHD_NX code on unstructured grids was developed to calculate the stability of two-dimensional equilibria with an arbitrary topology of magnetic surfaces. The study of equilibrium and stability of equilibrium configurations with toroidal current density reversal and axisymmetric n = 0 islands, which are associated with internal transport barrier and low current density at the magnetic axis, as well as with the operation of tokamaks in the alternating current regime, leads to more general issues of MHD stability of two-dimensional solutions of the Grad−Shafranov equations with islands under other types of symmetry—chain of islands in helical symmetry and cylindrically symmetric m = 0 islands in configurations with the longitudinal field reversal. New ideal MHD unstable modes have been discovered for various types of two-dimensional island configurations. The energy principle with MHD-compatible boundary conditions at open magnetic field lines is necessary for the self-consistent stability analysis of divertor configurations in tokamaks with a finite current density at the separatrix, taking into account the plasma outside the separatrix. Several codes have been developed for calculations of plasma equilibrium and stability, taking into account the influence of currents outside the separatrix, which are ready for integration with other codes for edge plasma modeling.

An Islanding Detection Test Platform for Multi-Inverter Islands Using Power HIL

When an unintentional island is formed on the electric power system, distributed energy resources (DERs) are typically required to detect and de-energize the island. This requirement may become more challenging as the number of DERs in an island rises. Thus, it is of interest to experimentally verify whether DERs can successfully detect and de-energize islands containing many DERs connected at different points. This paper presents a power hardware-in-the-loop (PHIL) platform for testing the duration of islands containing multiple inverters connected at multiple points in a network. The PHIL platform uses real-time simulation to represent islanded distribution circuits, with DER inverters connected in hardware. This allows efficient testing of a large number of island configurations simply by changing the distribution circuit model in the real-time simulator. A method for calculating the quality factor of an arbitrary distribution circuit in real time, designed for anti-islanding tests, is also presented. Experimental results are included demonstrating the use of the PHIL method to test a variety of three-inverter islands.

New insights into island vegetation composition and species diversity-Consistent and conditional responses across contrasting insular habitats at the plot-scale.

Most island-ecology studies focus on the properties of entire island communities, thus neglecting species-environment relationships operating at the habitat-level. Habitat-specific variation in the strength and sign of these relationships will conceal patterns observed on the island scale and may preclude a mechanistic interpretation of patterns and processes. Habitat-specific species-environment relationships may also depend on the descriptor of ecological communities. This paper presents a comprehensive plot-based analysis of local vegetation composition and species diversity (species richness and species evenness) of (i) rocky shore, (ii) semi-natural grassland and (iii) coniferous forest habitats in three Baltic archipelagos in Sweden. To identify differences and consistencies between habitats and descriptors, we assessed the relative contributions of the variable-sets “region”, “topography”, “soil morphology”, “soil fertility”, “soil water”, “light availability”, “distance” and “island configuration” on local vegetation composition, species richness and species evenness. We quantified the impact of “management history” on the descriptors of local grassland communities by a newly introduced grazing history index (GHI). Unlike species diversity, changes in vegetation composition were related to most of the variable-sets. The relative contributions of the variable-sets were mostly habitat-specific and strongly contingent on the descriptor involved. Within each habitat, richness and evenness were only partly affected by the same variable-sets, and if so, their relative contribution varied between diversity proxies. Across all habitats, soil variable-sets showed highly consistent effects on vegetation composition and species diversity and contributed most to the variance explained. GHI was a powerful predictor, explaining high proportions of variation in all three descriptors of grassland species communities. The proportion of unexplained variance was habitat-specific, possibly reflecting a community maturity gradient. Our results reveal that species richness alone is an incomplete representation of local species diversity. Finally, we stress the need of including habitat-based approaches when analyzing complex species-environment relationships on islands.

Boundary Detection and Enhancement Strategy for Power System Bus Bar Stabilization—Investigation under Fault Conditions for Islanding Operation

Distribution systems can form islands when faults occur. Each island represents a subsection with variable boundaries subject to the location of fault(s) in the system. A subsection with variable boundaries is referred to as an island in this paper. For operation in autonomous mode, it is imperative to detect the island configurations and stabilize these subsections. This paper presents a novel scheme for the detection of island boundaries and stabilizing the system during autonomous operation. In the first stage, a boundary detection method is proposed to detect the configuration of the island. In the second stage, a dynamic voltage sensitivity factor (DVSF) is proposed to assess the dynamic performance of the system. In the third stage, a wide area load shedding program is adopted based on DVSF to shed the load in weak bus-bars and stabilize the system. The proposed scheme is validated and tested on a generic 18-bus system using a combination of EMTDC/PSCAD and MATLAB software’s.

Numerical modeling study to compare the nutrient removal potential of different floating treatment island configurations in a stormwater pond

Constructed wetlands, which are commonly used in wastewater treatment, are difficult to use for stormwater treatment, because the water level variation in a stormwater pond makes it difficult for rooted vegetation to survive. As an alternative, vegetation can be grown on floating mats, called floating treatment islands (FTI), with roots extending downward into the water. Nutrient removal is achieved through uptake and trapping by the matrix of roots and bio-film. The overall treatment provided by a pond with FTIs depends on the fraction of flow exposed to the root zone. This study used numerical modeling to study the flow through the root zone, with the goal of determining which configuration of FTI achieved the greatest overall treatment. Six different configurations were considered, all with root zone volume equal to 11% of the pond volume. The permeability of the root zone was estimated using velocity measurements within real floating vegetation. A first-order removal rate within the root zone (kr) was estimated from removal rates reported in the literature. Preliminary studies considered the similarity in flow and removal between systems of different physical scale. Geometric similarity of the root zone guaranteed flow similarity within the root zone. To achieve performance similarity (same mass reduction), systems need to have the same non-dimensional removal rate (krtn, with tn the nominal residence time of the pond). The consideration of different FTI configurations showed that wakes generated by upstream FTIs lowered the mass removal of downstream FTIs, so that segmenting a single large FTI into multiple smaller FTIs in series did not improve overall nutrient removal. However, segmenting a single FTI into a pair of parallel FTIs did improve the nutrient removal, and this configuration provided the best pond-scale removal.

Active dependency formation in islands: How grammatical resumption affects sentence processing

Previous studies concluded that despite the parser’s eagerness to resolve filler-gap dependencies, in island configurations it prefers to posit late grammatical gaps over early ungrammatical ones. This study investigates the possibility of resolving filler-gap dependencies inside Hebrew islands. We investigated the acceptability of resumptive pronouns (RPs) in two islands and the sensitivity of on-line dependency formation to the status of those RPs. Results revealed a filled-gap effect inside the island that allows RPs but not inside the one that prohibits them. This suggests that active dependency formation can proceed inside islands, and that when processing dependencies with islands, the Hebrew parser prefers an early RP over a later gap.

Complete genome of Staphylococcus aureus Tager 104 provides evidence of its relation to modern systemic hospital-acquired strains.

BackgroundStaphylococcus aureus (S. aureus) infections range in severity due to expression of certain virulence factors encoded on mobile genetic elements (MGE). As such, characterization of these MGE, as well as single nucleotide polymorphisms, is of high clinical and microbiological importance. To understand the evolution of these dangerous pathogens, it is paramount to define reference strains that may predate MGE acquisition. One such candidate is S. aureus Tager 104, a previously uncharacterized strain isolated from a patient with impetigo in 1947.ResultsWe show here that S. aureus Tager 104 can survive in the bloodstream and infect naïve organs. We also demonstrate a procedure to construct and validate the assembly of S. aureus genomes, using Tager 104 as a proof-of-concept. In so doing, we bridged confounding gap regions that limited our initial attempts to close this 2.82 Mb genome, through integration of data from Illumina Nextera paired-end, PacBio RS, and Lucigen NxSeq mate-pair libraries. Furthermore, we provide independent confirmation of our segmental arrangement of the Tager 104 genome by the sole use of Lucigen NxSeq libraries filled by paired-end MiSeq reads and alignment with SPAdes software. Genomic analysis of Tager 104 revealed limited MGE, and a νSaβ island configuration that is reminiscent of other hospital acquired S. aureus genomes.ConclusionsTager 104 represents an early-branching ancestor of certain hospital-acquired strains. Combined with its earlier isolation date and limited content of MGE, Tager 104 can serve as a viable reference for future comparative genome studies.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-016-2433-8) contains supplementary material, which is available to authorized users.