Output Scales Research Articles

Underestimating the benefits of marine protected areas for the replenishment of fished populations

Marine protected areas (MPAs) are important tools for managing marine ecosystems. MPAs are expected to replenish nearby exploited populations through the natural dispersal of young, but the models that make these predictions rely on assumptions that have recently been demonstrated to be incorrect for most species of fish. A meta‐analysis showed that fish reproductive output scales “hyperallometrically” with fish mass, such that larger fish produce more offspring per unit body mass than smaller fish. Because fish are often larger inside MPAs, they should exhibit disproportionately higher reproductive output as compared to fish outside of MPAs. We explore the consequences of hyperallometric reproduction for a range of species for population replenishment and the productivity of exploited species. We show that the reproductive contribution of fish inside MPAs has been systematically underestimated and that fisheries yields can be enhanced by the establishment of reservoirs of larger, highly fecund fish.

Changes in Population Demography and Reproductive Output of the Invasive Hemigrapsus sanguineus (Asian Shore Crab) in the Long Island Sound from 2005 to 2017

Cross-intertidal transects at a western Long Island Sound estuary site provided estimates of the density of the non-native Hemigrapsus sanguineus (Asian Shore Crab) from 1998 to 2017, and measurements of crab size (carapace width; CW) from 2005 to 2017. Since 2001, average intertidal density declined by ∼5% per year. This decline was driven by decreases in the density of larger crabs, with consequent reductions in average and maximum sizes of both males and females. The proportion of the largest crabs (>24 mm CW) dropped from 10.1% of the population in 2005 to 1.4% in 2017. Individual reproductive output scales with size; thus, I estimate the loss of the largest females to have reduced population reproductive output by half between 2005 and 2017. Also, the frequency of ovigerous females in the smallest reproductively mature classes (12–14 mm CW) increased. Though the density and average size of Asian Shore Crab have declined significantly, resident and native crab populations have still not recovered.

Limited impact of big fish mothers for population replenishment

A recent meta-analysis by Barneche et al. (2018; Science, 360(6389): 642–645) shows that fish reproductive output scales hypergeometrically with female weight. This result challenges the common assumption that reproductive output is proportional to weight. The implication made is that current theory and practice severely underestimate the importance of larger females for population replenishment. Their example for cod (Gadus morhua) shows that current practice makes an error of 149%. By properly accounting for fish demography, we show that the error is maximally on the order of 10% and in most other fish stocks likely much less.

On the positional accuracy and maximum allowable scale of UAV-derived photogrammetric products for archaeological site documentation

Blending photogrammetric and Structure from Motion techniques with Unmanned Aerial Vehicles (UAV) is a commonly used approach for the documentation and analysis of archaeological sites. Using the dense 3D point clouds generated from these techniques, two main photogrammetric products are created: orthophotos and Digital Surfaces Models (DSM). Depending on the UAV technology, the flight parameters, the topography and land cover of the flown area, DSMs and orthophotos are delivered with varying positional accuracies and output scales. In this paper, the positional accuracy and maximum allowable scale of these products generated by complete automation of flight mode and processing workflow are assessed. Moreover, three known International Mapping Standards (IMS) are validated using independent checkpoints, obtained by geodetic Global Navigation Satellite Systems receivers, in two Spanish study areas. The results show that accurate photogrammetric products adapted to the IMS can be successfully obtained by the automation of the photogrammetric workflow.

Thermal sensation models: Validation and sensitivity towards thermo-physiological parameters

Thermal sensation models are commonly used to assess thermal perception in various indoor environments. However, using different models to evaluate the same environment can result in high discrepancies between the models' predictions, as they have been developed based on experimental data from various populations, use diverse input parameters, have different ranges of applicability and use different output scales. In this study, a validation of seven existing thermal sensation models has been performed based on literature data with regards to uniform steady-state and transient indoor environments. The environmental and personal parameters were selected following the experimental protocol and the needed thermo-physiological input parameters were obtained from a thermo-physiological model.Six models showed a good performance for the analyzed range of conditions, with a mean root-mean-square deviation equal to or lower than 1 thermal sensation unit, even beyond their original range of application. A sensitivity study towards thermo-physiological parameters was also performed, showing that the models are not equally influenced by some inaccuracies in these input parameters. Since thermal sensation models are often associated with different thermal sensation scales, the possibility of applying a scaling to the predictions has been considered. However, the scaling did not consistently improve the predictions accuracy.

An incremental non-iterative learning method for one-layer feedforward neural networks

In machine learning literature, and especially in the literature referring to artificial neural networks, most methods are iterative and operate in batch mode. However, many of the standard algorithms are not suitable for efficiently managing the emerging large-scale data sets obtained from new real-world applications. Novel proposals to address these challenges are mainly iterative approaches based on incremental or distributed learning algorithms. However, the state-of-the-art is such that there are few learning methods based on non-iterative approaches, which have certain advantages over iterative models in dealing more efficiently with these new challenges. We have developed a non-iterative, incremental and hyperparameter-free learning method for one-layer feedforward neural networks without hidden layers. This method efficiently obtains the optimal parameters of the network, regardless of whether the data contains a greater number of samples than variables or vice versa. It does this by using a square loss function that measures errors before the output activation functions and scales them by the slope of these functions at each data point. The outcome is a system of linear equations that obtain the network's weights and that is further transformed using Singular Value Decomposition. We analyze the behavior of the algorithm, comparing its performance and scaling properties to other state-of-the-art approaches. Experimental results demonstrate that the proposed method appropriately solves a wide range of classification problems and is able to efficiently deal with large-scale tasks.

Impact of a workplace \u2018sit less, move more\u2019 program on efficiency-related outcomes of office employees

BackgroundFew studies have examined the impact of ‘sit less, move more’ interventions on workplace performance. This study assessed the short and mid-term impacts of and patterns of change within, a 19-week workplace web-based intervention (Walk@WorkSpain; W@WS; 2010–11) on employees´ presenteeism, mental well-being and lost work performance.MethodsA site randomised control trial recruited employees at six Spanish university campuses (n = 264; 42 ± 10 years; 171 female), assigned by worksite and campus to an Intervention (IG; used W@WS; n = 129; 87 female) or an active Comparison group (A-CG; pedometer, paper diary and self-reported sitting time; n = 135; 84 female). A linear mixed model assessed changes between the baseline, ramping (8 weeks), maintenance (11 weeks) and follow-up (two months) phases for the IG versus A-CG on (i) % of lost work productivity (Work Limitations Questionnaire; WLQ); (ii) three scales for presenteeism (WLQ) assessing difficulty meeting scheduling demands (Time), performing cognitive and inter-personal tasks (Mental-Interpersonal) and decrements in meeting the quantity, quality and timeliness of completed work (Output); and (iii) mental well-being (Warwick-Edinburgh Mental Well-being Scale). T-tests assessed differences between groups for changes on the main outcomes. In the IG, a multivariate logistic regression model identified patterns of response according to baseline socio-demographic variables, physical activity and sitting time.ResultsThere was a significant 2 (group) × 2 (program time points) interaction for the Time (F [3]=8.69, p = 0.005), Mental-Interpersonal (F [3]=10.01, p = 0.0185), Output scales for presenteeism (F [3]=8.56, p = 0.0357), and for % of lost work performance (F [3]=10.31, p = 0.0161). Presenteeism and lost performance rose significantly in both groups across all study time points; after baseline performance was consistently better in the IG than in the A-CG. Better performance was linked to employees being more active (Time, p = 0.041) and younger (Mental-interpersonal, p = 0.057; Output, p = 0.017). Higher total sitting time during nonworking days (Mental-interpersonal, p = 0.019) and lower sitting time during workdays (WLQ Index, p = 0.013) also improved performance.ConclusionVersus an active comparison condition, a ‘sit less, move more` workplace intervention effectively reduced an array of markers of lost workday productivity.Trial registrationNCT02960750; Date of registration: 07/11/2016.

Specific Surface Nitride Groups on Glassy Carbon Model Surfaces to Catalyze the Vanadium Redox Reactions

Vanadium redox flow batteries currently have come closer to their suitability in the industrial as well as the private sector. However, they still suffer from high capital costs, mainly ruled by the conversion unit consisting of an assembly of sandwiched components, such as semipermeable membranes and carbon electrodes (MEA). The respective system power output scales with and determines the necessary geometric area of the MEA. By increasing the area specific power output of a MEA capital costs may be reduced. As electrodes commonly porous graphite felt (GF) electrodes are used which are made of a woven of carbon fibers. When pumping the (sulfuric acid) electrolyte through these graphite felts, the Vanadium (V) ions dissolved in the electrolyte can pass the carbon surface of the fibers where the anodic V2+/3+ and the cathodic V4+/5+ redox reactions take place, respectively. A big portion of the power losses result from the kinetic overpotentials that need to be applied on the porous carbon electrodes in order to drive the Vanadium reactions.(1) In recent years various modification methods of the carbon electrodes have been proposed.(2,3) Besides surface oxide groups there were a few attempts that involved nitrogen atoms which were supposed to offer a catalytic activity for the Vanadium reactions. This work aims to resolve the variable catalytic activity coming from distinctive nitride surface groups.(4,5) For this purpose, on glassy carbon there were synthesized artificial aromates containing a nitro group, which covalently bind to the carbon surface and provide an anchor site for the Vanadium redox reaction. The synthesis method is resulting in a narrow distribution of architecture of different surface nitrides. This allows for an exclusive examination of the catalysis of distinctive, specific nitrogen involving surface groups for the Vanadium reactions and shows pathways for advanced modification methods. Experimental results will comprise rotating disk electrode (RDE) measurements in an electrochemical half-cell. Moreover, x-ray photoemission spectroscopy results depict the surface coverage of the newly created adsorbants. In addition, the performance and changed efficiency of a single cell is presented, which is equipped with GF electrodes comprising the surface nitrides evaluated before. The project is financially supported by the Bavarian Ministry of Economics. (1) Parasuraman et al. Electrochimica Acta (2013) 101 27–40. (2) J.-Z. Chen et al. Journal of Power Sources (2015) 274 894–898. (3) K.J.Kim et al. Mat. Chem. And Phys. (2011) 131 547-553. (4) S. Wang et al. J. Phys. Chem. Lett. (2012) 3 2164−2167. (5) Y. Shao et al. Journal of Power Sources (2010) 195 4375–4379.

Coherence-Induced Reversibility and Collective Operation of Quantum Heat Machines via Coherence Recycling

Collective behavior where a set of elements interact and generate effects that are beyond the reach of the individual non interacting elements, are always of great interest in physics. Quantum collective effects that have no classical analogue are even more intriguing. In this work we show how to construct collective quantum heat machines and explore their performance boosts with respect to regular machines. Without interactions between the machines the individual units operate in a stochastic, non-quantum manner. The construction of the collective machine becomes possible by introducing two simple quantum operations: coherence extraction and coherence injection. Together these operations can harvest coherence from one engine and use it to boost the performance of a slightly different engine. For weakly driven engines we show that the collective work output scales quadratically with the number of engines rather than linearly. Eventually, the boost saturates and the scaling becomes linear. Nevertheless, even in saturation, work is still significantly boosted compared to individual operation. To study the reversibility of the collective machine we introduce the 'entropy pollution' measure. It is shown that there is a regime where the collective machine is N times more reversible while producing N times more work, compared to the individual operation of N units. Moreover, the collective machine can even be more reversible than the most reversible unit in the collective. This high level of reversibility becomes possible due to a special symbiotic mechanism between engine pairs.

All-electrical detection of spin dynamics in magnetic antidot lattices by the inverse spin Hall effect

The understanding of spin dynamics in laterally confined structures on sub-micron length scales has become a significant aspect of the development of novel magnetic storage technologies. Numerous ferromagnetic resonance measurements, optical characterization by Kerr microscopy and Brillouin light scattering spectroscopy and x-ray studies were carried out to detect the dynamics in patterned magnetic antidot lattices. Here, we investigate Oersted-field driven spin dynamics in rectangular Ni80Fe20/Pt antidot lattices with different lattice parameters by electrical means and compare them to micromagnetic simulations. When the system is driven to resonance, a dc voltage across the length of the sample is detected that changes its sign upon field reversal, which is in agreement with a rectification mechanism based on the inverse spin Hall effect. Furthermore, we show that the voltage output scales linearly with the applied microwave drive in the investigated range of powers. Our findings have direct implications on the development of engineered magnonics applications and devices.

Piezoelectric Size Effects in a Zinc Oxide Micropillar.

In this work, the dependence of piezoelectric coefficients (PE) on the size of artificial fabricated ZnO micropillars on Si substrate is investigated. ZnO full film is grown with c-axis orientation and an average grain size of 20 nm at a substrate temperature of 500 °C by pulsed laser ablation. The micropillars with the size range of 1.5 to 7 μm are formed by top-down semiconductor device processing. The PE, characterized by piezoelectric force microscopy (PFM), is found to increase from 18.2 to 46.9 pm/V, when the ZnO pillar size is reduced from 7 to 1.5 μm. The strong PE dependence on ZnO pillar size can be explained by local changes in polarization and reduction of unit cell volume with respect to bulk values. These results have strong implications in the field of energy harvesting, as piezoelectric voltage output scales with the piezoelectric coefficient.

From senses to texts: An all-in-one graph-based approach for measuring semantic similarity

Quantifying semantic similarity between linguistic items lies at the core of many applications in Natural Language Processing and Artificial Intelligence. It has therefore received a considerable amount of research interest, which in its turn has led to a wide range of approaches for measuring semantic similarity. However, these measures are usually limited to handling specific types of linguistic item, e.g., single word senses or entire sentences. Hence, for a downstream application to handle various types of input, multiple measures of semantic similarity are needed, measures that often use different internal representations or have different output scales. In this article we present a unified graph-based approach for measuring semantic similarity which enables effective comparison of linguistic items at multiple levels, from word senses to full texts. Our method first leverages the structural properties of a semantic network in order to model arbitrary linguistic items through a unified probabilistic representation, and then compares the linguistic items in terms of their representations. We report state-of-the-art performance on multiple datasets pertaining to three different levels: senses, words, and texts.

Clinical Changes in Older Adults During Hospitalization: Responsiveness of the interRAI Acute Care Instrument

To evaluate the responsiveness of the Minimum Data Set interRAI Acute Care (AC), a comprehensive geriatric assessment system, to detect clinical changes in patient status during hospital stays. An explorative secondary data-analysis comparing prospectively collected data with the interRAI AC before hospitalization, upon admission, and at discharge. Clinicians from multiple disciplines in nine geriatric and eight nongeriatric wards of nine acute hospitals performed the assessment. The interRAI AC was administered serially to 256 geriatric inpatients (aged 83.2 ± 5.2; 60% female). Responsiveness (capacity to detect changes in patients) was calculated for the output scales on five domains: activities of daily living (ADLs), cognition, communication, depressive symptoms, and pain. Internal responsiveness was evaluated using the Friedman test and Guyatt technique. Significant differences in clinical status were found for all five domains, based on the Friedman test. Post hoc tests revealed differences between each assessment period, except for cognition and communication from admission to discharge and for depressive symptoms from before admission to discharge. The Guyatt Responsiveness Index showed good to excellent capacity to detect longitudinal changes during hospitalization for cognition, communication, and pain and substantial performance for ADLs and depressive symptoms. In older inpatients, fluctuations in ADLs, cognition, communication, depressive symptoms, and pain can be captured using the interRAI AC output scales, enabling clinicians to evaluate longitudinal changes from admission to discharge and to provide a comparison with patient status before the acute onset of the illness. These results support the use of these scales in geriatric and nongeriatric wards.

Imaging Properties of Scintillation Screens for High Energetic Ion Beams

The imaging properties of various scintillation screens were investigated for ion beams extracted from the heavy ion synchrotron SIS 18 at GSI. Different ion beams such as C, Ne, Ar, Ta and U with initial kinetic energy of about 300 MeV/u were applied to various scintillation screens with particle fluxes ranging from 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> to 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">9</sup> particles per pulse typically within 0.3 s pulse length. The scintillation process was observed with a digital Charge Coupled Device (CCD) camera. The performed study compares the light output, the beam profiles, and the image deformation of various scintillating screens for different ion beams. The light output scales linearly with respect to the ion beam flux over five orders of magnitude for the sensitive scintillation screens and ceramics like Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> , Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> :Cr. The highest light output was observed for CsI:Tl, and the lowest was recorded for Herasil. At higher beam intensities, non linear behavior of light output was observed for Mg and Y doped ZrO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> samples. The recorded beam profiles showed differences in width up to 50%, depending on the screen material.

Modeling Agricultural Nonpoint Source Pollution Using a Geographic Information System Approach

Agricultural non-point source (NPS) pollution, primarily sediment and nutrients, is the leading source of water-quality impacts to surface waters in North America. The overall goal of this study was to develop geographic information system (GIS) protocols to facilitate the spatial and temporal modeling of changes in soils, hydrology, and land-cover change at the watershed scale. In the first part of this article, we describe the use of GIS to spatially integrate watershed scale data on soil erodibility, land use, and runoff for the assessment of potential source areas within an intensively agricultural watershed. The agricultural non-point source pollution (AGNPS) model was used in the Muddy Creek, Ontario, watershed to evaluate the effectiveness of management strategies in decreasing sediment and nutrient [phosphorus (P)] pollution. This analysis was accompanied by the measurement of water-quality parameters (dissolved oxygen, pH, hardness, alkalinity, and turbidity) as well as sediment and P loadings to the creek. Practices aimed at increasing year-round soil cover would be most effective in decreasing sediment and P losses in this watershed. In the second part of this article, we describe a method for characterizing land-cover change in a dynamic urban fringe watershed. The GIS method we developed for the Blackberry Creek, Illinois, watershed will allow us to better account for temporal changes in land use, specifically corn and soybean cover, on an annual basis and to improve on the modeling of watershed processes shown for the Muddy Creek watershed. Our model can be used at different levels of planning with minimal data preprocessing, easily accessible data, and adjustable output scales.

Allocating fixed costs and common revenue via data envelopment analysis

An issue of considerable importance involves the allocation of fixed costs or common revenue among a set of competing entities in an equitable way. Based on the data envelopment analysis (DEA) theory, this paper proposes new methods for (i) allocating fixed costs to decision making units (DMUs) and (ii) distributing common revenue among DMUs, in such a way that the relative efficiencies of all DMUs remain unchanged and the allocations should reflect the relative efficiencies and the input–output scales of individual DMUs. To illustrate our methods, numerical results for an example are described in this paper.

Giant Piezoelectric Size Effects in Zinc Oxide and Gallium Nitride Nanowires. A First Principles Investigation

Nanowires made of materials with noncentrosymmetric crystal structure are under investigation for their piezoelectric properties and suitability as building blocks for next-generation self-powered nanodevices. In this work, we investigate the size dependence of piezoelectric coefficients in nanowires of two such materials - zinc oxide and gallium nitride. Nanowires, oriented along their polar axis, ranging from 0.6 to 2.4 nm in diameter were modeled quantum mechanically. A giant piezoelectric size effect is identified for both GaN and ZnO nanowires. However, GaN exhibits a larger and more extended size dependence than ZnO. The observed size effect is discussed in the context of charge redistribution near the free surfaces leading to changes in local polarization. The study reveals that local changes in polarization and reduction of unit cell volume with respect to bulk values lead to the observed size effect. These results have strong implication in the field of energy harvesting, as piezoelectric voltage output scales with the piezoelectric coefficient.

Room temperature continuous wave milliwatt terahertz source

We present a continuous wave terahertz source based on intracavity difference frequency generation within a dual color vertical external cavity surface emitting laser. Using a nonlinear crystal with a surface emitting phase matching scheme allows for high conversion efficiencies. Due to the tunability of the dual mode spacing, the entire spectral range of the terahertz gap can be covered. The terahertz output scales quadratically with the intracavity intensity, potentially allowing for terahertz intensities in the range of 10s of milliwatts and beyond.

Theoretical analysis of single-frequency Raman fiber amplifier system operating at 1178nm

We analyze the scalability of amplifying the output from a single-frequency diode laser operating at 1178 nm through the utilization of a core pumped Raman fiber amplifier. A detailed model that accounts for stimulated Raman scattering (SRS) and stimulated Brillouin scattering (SBS) in relation to the fiber mode field diameter, length, seed power, and available pump power in both co-pumped and counter-pumped configurations is developed. The backward travelling Stokes light is initiated from both spontaneous Brillouin and spontaneous Raman processes. It is found that when fiber length is optimized, the amplifier output scales linearly with available pump power. Although higher amplifier efficiency is obtained with higher seed power, the output power diminishes. In order to mitigate the SBS process for further power scaling, we employ and optimize a multi-step temperature distribution. Finally, we consider the feasibility of generating the D(2a) and D(2b) lines in a sodium guide star beacon from a single Raman amplifier by examining four-wave mixing (FWM).

Zolpidem Extended-Release 12.5 mg Associated with Improvements in Work Performance in a 6-Month Randomized, Placebo-Controlled Trial

Although most research on pharmacotherapy for chronic insomnia focuses on changes in sleep outcomes, the functional impact of treatment is also of great importance to patients, families, physicians, and employers. To analyze changes in functioning at work (or work performance) among a subset of employed subjects (N = 752) from a 24-week, randomized, double-blind, placebo-controlled trial of zolpidem extended-release 12.5 mg taken nightly, at least 3 nights per week, by healthy adults with chronic insomnia. Using 2 scales (Time Management and Work Output) from the Work Limitations Questionnaire (WLQ), subjects' health-related work limitations were evaluated at baseline, week 4, week 12, and week 24 (end of study) or premature discontinuation. To compare zolpidem extended-release 12.5 mg with placebo, within-group and between-group differences were analyzed and effect sizes were computed. The relationship of WLQ scores to scores on the Patient Global Impression, Item 1 (PGI-1), scale, the primary outcome measure for benefit to sleep, was also analyzed. Data were obtained from August 31, 2004 through January 6, 2006. Scores on both WLQ scales were substantially elevated at baseline in this population, reflecting impairment relative to healthy controls. The zolpidem extended-release 12.5 mg group had significantly greater improvement at all time points on the WLQ Time Management (P < 0.0001) and Work Output (P < 0.01) scales. Effect size analysis confirmed the clinical relevance of these improvements. Subjects rating their sleep as improved on the PGI-1 had significantly greater improvement on both WLQ scales at week 12 than did those who reported no benefit or worsening (P < 0.01). Employed adults with chronic insomnia treated with zolpidem extended-release 12.5 mg experienced significantly improved work performance over 24 weeks.