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Journal articles on the topic 'Metrica frw'

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Published: 4 June 2021
Last updated: 10 February 2022

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1

Moradpour, H., A. Dehghani, and M. T. Mohammadi Sabet. "Dynamic black holes in an FRW background: Lemaître transformations." Modern Physics Letters A 30, no. 39 (December 7, 2015): 1550207. http://dx.doi.org/10.1142/s0217732315502077.

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Since the conformal transformations of metric do not change its causal structure, we use these transformations to embed the Lemaître metrics into the FRW background. In our approach, conformal transformation is in agreement with the universe expansion regimes. Indeed, we use the Lemaître metrics because the horizon singularity is eliminated in these metrics. Moreover, some physical and mathematical properties of the introduced metrics have been addressed. We show that the resultant metrics include event horizons while their physical radii are increasing as a function of the universe expansion which may provide suitable metrics for investigating the effects of the universe expansion on the black holes.
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Iihoshi, M., S. V. Ketov, and A. Morishita. "Conformally Flat FRW Metrics." Progress of Theoretical Physics 118, no. 3 (September 1, 2007): 475–89. http://dx.doi.org/10.1143/ptp.118.475.

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3

KHOSRAVI, SHAHRAM, REZA MANSOURI, and EHSAN KOURKCHI. "MODIFIED AVERAGING PROCESSES IN COSMOLOGY AND THE STRUCTURED FRW MODEL." International Journal of Modern Physics D 18, no. 07 (July 2009): 1177–92. http://dx.doi.org/10.1142/s0218271809015011.

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We study the volume averaging of inhomogeneous metrics within GR and discuss its shortcomings, such as gauge dependence, singular behavior as a result of caustics, and causality violations. To remedy these shortcomings, we suggest some modifications to this method. As a case study we focus on the inhomogeneous structured FRW model based on a flat LTB metric. The effect of averaging is then studied in terms of an effective backreaction fluid. It is shown that, contrary to the claims in the literature, the backreaction fluid behaves like a dark matter component, instead of dark energy, having a density of the order of 10-5 times the matter density, and, most importantly, it is gauge-dependent.
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4

Gao, Chang Jun, and Shuang Nan Zhang. "Higher dimensional Reissner-Nordström-FRW metric." General Relativity and Gravitation 38, no. 1 (January 2006): 23–32. http://dx.doi.org/10.1007/s10714-005-0207-8.

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Carvalho, A. M. de M., and Claudio Furtado. "Holonomy transformation in the FRW metric." General Relativity and Gravitation 39, no. 9 (June 6, 2007): 1311–22. http://dx.doi.org/10.1007/s10714-007-0443-1.

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BOWDITCH, BRIAN H. "Median and injective metric spaces." Mathematical Proceedings of the Cambridge Philosophical Society 168, no. 1 (July 27, 2018): 43–55. http://dx.doi.org/10.1017/s0305004118000555.

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AbstractWe describe a construction which associates to any median metric space a pseudometric satisfying the binary intersection property for closed balls. Under certain conditions, this implies that the resulting space is, in fact, an injective metric space, bilipschitz equivalent to the original metric. In the course of doing this, we derive a few other facts about median metrics, and the geometry of CAT(0) cube complexes. One motivation for the study of such metrics is that they arise as asymptotic cones of certain naturally occurring spaces.
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Torres-Jr, Pedro Rodrigues, and Eduardo Parente Ribeiro. "Packet Reordering Metrics to Enable Performance Comparison in IP-Networks." Journal of Computer Networks and Communications 2020 (May 30, 2020): 1–8. http://dx.doi.org/10.1155/2020/8465191.

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Despite the existence of several metrics to perform measurements on out-of-order packets, few works have used these metrics for comparative purposes. A potential reason for this is that the use of these simple singleton metrics makes it difficult to analyze all the effects of packet reordering. On the other hand, more complete metrics are represented in a vectorial manner, making comparative analysis challenging. In this paper, we present a scenario for testing and describe a methodology for conducting experiments to compare network paths with respect to unordered packets. The results of several simulations explore simple packet reordering metrics derived from vector metric that may allow future work to be benchmarked against. We demonstrated the behaviour of some TCP congestion control algorithms by adjusting different levels of reordering. We highlight good results with the Entropy reorder metric.
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Fuster-Parra, Pilar, Javier Martín, Jordi Recasens, and Óscar Valero. "T-Equivalences: The Metric Behavior Revisited." Mathematics 8, no. 4 (April 2, 2020): 495. http://dx.doi.org/10.3390/math8040495.

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Since the notion of T-equivalence, where T is a t-norm, was introduced as a fuzzy generalization of the notion of crisp equivalence relation, many researchers have worked in the study of the metric behavior of such fuzzy relations. Concretely, a few techniques to induce metrics from T-equivalences, and vice versa, have been developed. In several fields of computer science and artificial intelligence, a generalization of pseudo-metric, known as partial pseudo-metrics, have shown to be useful. Recently, Bukatin, Kopperman and Matthews have stated that the notion of partial pseudo-metric and a type of generalized T-equivalence are linked. Inspired by the preceding fact, in this paper, we state a concrete relationship between partial pseudo-metrics and the aforesaid generalized T-equivalences. Specifically, a method for constructing partial pseudo-metrics from the new type of T-equivalences and, reciprocally, for constructing the generalized T-equivalences from partial pseudo-metrics are provided. However, important differences between the new approach and the classical one are established. Special interest is paid to the case in which the minimum, drastic, and Łukasiewicz t-norms are under consideration.
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Lehuta, Sigrid, Stéphanie Mahévas, Pascal Le Floc’h, and Pierre Petitgas. "A simulation-based approach to assess sensitivity and robustness of fisheries management indicators for the pelagic fishery in the Bay of Biscay." Canadian Journal of Fisheries and Aquatic Sciences 70, no. 12 (December 2013): 1741–56. http://dx.doi.org/10.1139/cjfas-2013-0066.

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Indicators are widely promoted as means to monitor ecosystem status or to evaluate fisheries management performance. “Which indicators are most relevant as decision-support tools in fisheries management?” still remains a topical question. Indicators should be metrics related to fish populations and fleets and should be sensitive to management strategies. However, given the complexity of the processes involved, it is often difficult to unequivocally interpret variations in metrics. A simulation approach was used to study metric properties and to identify robust and relevant fishery indicators. By applying sensitivity analysis methods, simulation designs were built that cross a variety of management scenarios and uncertainty hypotheses. Bio-economic outputs were simulated using a mechanistic model (ISIS-Fish), and their properties were statistically analyzed. This approach was applied to the pelagic fishery of the Bay of Biscay. The analysis of metric properties highlighted the major factors driving variations in each metric and identified the important sources of uncertainty that need to be reduced to allow the use of metrics as indicators. Although very few metrics gave robust indications of management performance, sensitivity indices evidenced how management performances could be improved, and spatially disaggregated metrics provided insights into the mechanisms underlying management performance.
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10

Ali, Sarfraz, Sabir Iqbal, Khuram Ali Khan, and Hamid Reza Moradi. "Amended FRW Metric and Rényi Dark Energy Model." Advances in High Energy Physics 2021 (June 15, 2021): 1–9. http://dx.doi.org/10.1155/2021/9704909.

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This article is devoted to exploring the Rényi holographic dark energy model in the theory of Chern-Simons modified gravity. We studied the deceleration parameter, equation of state, and cosmological plane considering the Amended FRW modal. Modified field equations of -gravity theory gave two independent solutions. In the first case, this model provided the transitional change from deceleration to acceleration compatible with collected observational data. However, it supported a decelerating phase of expansion only in the second case. It was noted that the Equation of State advocated the dominance era under the influence of dark energy in the first case and the second predicted the influence of Λ CDM. In both cases, ω < 0 , ω ′ < 0 voted that the universe is in a freezing region and its cosmic expansion is more rapidly accelerated in the background of Chern-Simons modified gravity.
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Huang, Yan, Yang Long, and Liang Wang. "Few-Shot Image and Sentence Matching via Gated Visual-Semantic Embedding." Proceedings of the AAAI Conference on Artificial Intelligence 33 (July 17, 2019): 8489–96. http://dx.doi.org/10.1609/aaai.v33i01.33018489.

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Although image and sentence matching has been widely studied, its intrinsic few-shot problem is commonly ignored, which has become a bottleneck for further performance improvement. In this work, we focus on this challenging problem of few-shot image and sentence matching, and propose a Gated Visual-Semantic Embedding (GVSE) model to deal with it. The model consists of three corporative modules in terms of uncommon VSE, common VSE, and gated metric fusion. The uncommon VSE exploits external auxiliary resources to extract generic features for representing uncommon instances and words in images and sentences, and then integrates them by modeling their semantic relation to obtain global representations for association analysis. To better model other common instances and words in rest content of images and sentences, the common VSE learns their discriminative representations directly from scratch. After obtaining two similarity metrics from the two VSE modules with different advantages, the gated metric fusion module adaptively fuses them by automatically balancing their relative importance. Based on the fused metric, we perform extensive experiments in terms of few-shot and conventional image and sentence matching, and demonstrate the effectiveness of the proposed model by achieving the state-of-the-art results on two public benchmark datasets.
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Boubekri, Mohamed, and Jaewook Lee. "A COMPARISON OF FOUR DAYLIGHTING METRICS IN ASSESSING THE DAYLIGHTING PERFORMANCE OF THREE SHADING SYSTEMS." Journal of Green Building 12, no. 3 (September 2017): 39–53. http://dx.doi.org/10.3992/1943-4618.12.3.39.

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The assessment of the daylighting performance of a design solution is a complex task due to the changing nature of daylight. A few quantitative metrics are available to designers to assess such a performance, among them are the mean hourly illuminance (MHI), the daylight factor (DF), the daylight autonomy (DA) and the useful daylight illuminance (UDI). Each of these metrics has a purpose, a set of criteria and limitations that affect the outcome of the evaluation. When to use one metric instead of another depends largely on the design goals to be achieved. Using Design Iterate Validate Adapt (DIVA) daylighting simulation program, we set out to examine the performance behavior of these four metrics with the changing dimensions of three shading devices: a horizontal overhang, a horizontal louver system, and a vertical fin system, and compare their performance behavior as the orientation changes of the window to which these devices are attached. The context is a typical classroom of a prototypical elementary school. Our results indicate that not all four metrics behave similarly as we vary the size of each shading device and as orientation changes. The lesson learned is that not all daylighting metrics lead to the same conclusions and that it is important to use the metric that corresponds to the specific goals and objectives of the design and of the daylighting solution. The UDI is the metric that leads to outcomes most different than the other three metrics investigated in this paper.
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13

ZORBA, S. "A MODIFIED FRW METRIC TO EXPLAIN THE COSMOLOGICAL CONSTANT." Modern Physics Letters A 27, no. 19 (June 21, 2012): 1250106. http://dx.doi.org/10.1142/s0217732312501064.

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One of the most outstanding problems of the standard model of cosmology today is the problem of cosmological constant/dark energy. It corresponds to about 73% of the energy content of the universe gone missing. I hereby postulate a modified FRW metric for our universe, which animates a universe spinning very slowly with an angular frequency that is equal to the Hubble's constant. It is shown by a simple argument that in such a universe there will be an overlooked rotational energy whose average value is identically equal to the matter-energy content of this universe as observed by a coordinate observer. The corresponding Friedmann equation is derived, whereby the overlooked rotational energy naturally becomes the cosmological constant/dark energy term without artificially/mysteriously adding any such term, as is commonly done. The proposed model also produces Hubble's law naturally.
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14

Johri, VB, and R. Sudharsan. "BD-FRW Cosmology with Bulk Viscosity." Australian Journal of Physics 42, no. 2 (1989): 215. http://dx.doi.org/10.1071/ph890215.

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Exact cosmological solutions of the field equations in Brans-Dicke (BD) theory, with k = 0, FRW metric have been obtained in the presence of bulk viscosity. It is found that constant bulk viscosity leads to an inflationary solution for large values of the BD coupling parameter w. The case of radiative bulk viscosity during the decoupling era is investigated and the production of entropy is estimated.
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15

GHANEH, T., F. DARABI, and H. MOTAVALLI. "SIGNATURE CHANGE BY GUP." International Journal of Modern Physics D 22, no. 05 (April 2013): 1350026. http://dx.doi.org/10.1142/s0218271813500260.

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We revisit the issue of continuous signature transition from Euclidean to Lorentzian metrics in a cosmological model described by Friedmann–Robertson–Walker (FRW) metric minimally coupled with a self-interacting massive scalar field. Then, using a noncommutative (NC) phase space of dynamical variables deformed by generalized uncertainty principle (GUP), we show that the signature transition occurs even for a model described by the FRW metric minimally coupled with a free massless scalar field accompanied by a cosmological constant. This indicates that the continuous signature transition might have been easily occurred at early universe just by a free massless scalar field, a cosmological constant and a NC phase space deformed by GUP, without resorting to a massive scalar field having an ad hoc complicate potential. We also study the quantum cosmology of the model and obtain a solution of Wheeler–DeWitt (WD) equation which shows a good correspondence with the classical path.
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16

Piratla, Kalyan R., and Samuel T. Ariaratnam. "Assessment of metrics for resilient design of water distribution networks." Journal of Water Supply: Research and Technology-Aqua 64, no. 6 (June 5, 2015): 660–69. http://dx.doi.org/10.2166/aqua.2015.014.

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Water distribution networks (WDNs) play a crucial role in the well-being of human populations and economic prosperity. It is essential that they cope with abnormal operating conditions and recover functionality quickly. Traditionally, WDNs are designed using cost and reliability objectives, but there is a lack of consensus on the definition and quantification of reliability which typically is a computationally intense process. Subsequently, various reliability-like metrics, called resilience indices, have been developed and demonstrated in the design of WDNs. Few studies exist that thoroughly evaluate the performance of the previously developed resilience metrics. This paper investigates three resilience metrics by evaluating their performance on three benchmark WDNs for several simulated mechanical failure states. The metrics studied are: (a) resilience index, (b) network resilience index (NRI), and (c) modified resilience index (MRI). The metric MRI performed better overall but NRI produced cheaper designs that performed better in the case of WDN-I. It is recommended that a better metric that incorporates different dimensions of resilience, such as robustness and redundancy, should be developed in the future.
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17

Wang, Juan, and Maozu Guo. "A review of metrics measuring dissimilarity for rooted phylogenetic networks." Briefings in Bioinformatics 20, no. 6 (July 17, 2018): 1972–80. http://dx.doi.org/10.1093/bib/bby062.

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Abstract A rooted phylogenetic network is an important structure in the description of evolutionary relationships. Computing the distance (topological dissimilarity) between two rooted phylogenetic networks is a fundamental in phylogenic analysis. During the past few decades, several polynomial-time computable metrics have been described. Here, we give a comprehensive review and analysis on those metrics, including the correlation among metrics and the distribution of distance values computed by each metric. Moreover, we describe the software and website, CDRPN (Computing Distance for Rooted Phylogenetic Networks), for measuring the topological dissimilarity between rooted phylogenetic networks. Availability http://bioinformatics.imu.edu.cn/distance/ Contact guomaozu@bucea.edu.cn
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18

ALDEA, NICOLETA, and GHEORGHE MUNTEANU. "NEW CANDIDATES FOR A HERMITIAN APPROACH OF GRAVITY." International Journal of Geometric Methods in Modern Physics 10, no. 09 (August 30, 2013): 1350041. http://dx.doi.org/10.1142/s0219887813500412.

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In this paper, some possible candidates for the study of gravity are proposed in terms of complex Finsler geometry. These mainly concern the complex Hermitian versions of weakly gravitational metric and Schwarzschild metric. For the weakly gravitational fields, we state few interesting geometrical and physical aspects such as the conditions under which a complex Finsler metrics are projectively related to the weakly gravitational metric. In the Kähler case, the geodesic curves of the weakly gravitational metric are obtained. Some applications concerning the deformations of the weakly gravitational Hermitian metric to a complex Randers metric are described. Another candidate for gravity is given by so-called Hermitian Schwarzschild metric for which some geodesic curves are highlighted. The last part of the paper is devoted to a generalization of the complex Klein–Gordon equations, in terms of Quantum field theory on a curved space.
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19

Wienold, J., T. Iwata, M. Sarey Khanie, E. Erell, E. Kaftan, RG Rodriguez, JA Yamin Garreton, et al. "Cross-validation and robustness of daylight glare metrics." Lighting Research & Technology 51, no. 7 (March 14, 2019): 983–1013. http://dx.doi.org/10.1177/1477153519826003.

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This study evaluates the performance and robustness of 22 established and newly proposed glare prediction metrics. Experimental datasets of daylight-dominated workplaces in office-like test rooms were collected from studies by seven research groups in six different locations (Argentina, Denmark, Germany, Israel, Japan and the United States). The variability in experimental setups, locations and research teams allowed reliable evaluation of the performance and robustness of glare metrics for daylight-dominated workplaces. Independent statistical methods were applied to individual datasets and also to one combined dataset to evaluate the performance and robustness of the 22 glare metrics. As performance and robustness are not established in literature, we defined performance as: (1) the ability of the metric value to describe the glare scale (evaluated by Spearman rank correlation), and (2) the ability of the metric to distinguish between disturbing and non-disturbing situations (evaluated by diagnostic receiver operating characteristic curve analysis tests). Furthermore, we defined robustness as the ability of a metric to deliver meaningful results when applied to different datasets and to fail as few as possible statistical tests. Average Spearman rank correlation coefficients in the range of 0.55–0.60 as well as average prediction rates to distinguish between disturbing and non-disturbing glare of 70–75% for several of the metrics indicate their reliability. The results also show that metrics considering the saturation effect as a main input in their equation perform better and are more robust in daylight-dominated workplaces than purely contrast-based metrics or purely empirical metrics. In this study, the daylight glare probability (DGP) delivered the highest performance amongst the tested metrics and was also found to be the most robust. Future research should aim to optimise the terms of glare equations which combine contrast and saturation effects, such as DGP, PGSV or UGRexp, to achieve metrics that also perform reliably in dimmer lighting conditions than the ones explored in this study.
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20

Moradpour, H., and N. Riazi. "Spherically symmetric solutions in a FRW background." Modern Physics Letters A 30, no. 08 (March 4, 2015): 1550042. http://dx.doi.org/10.1142/s021773231550042x.

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We impose perfect fluid concept along with slow expansion approximation to derive new solutions which, considering non-static spherically symmetric metrics, can be treated as Black Holes (BHs). We will refer to these solutions as Quasi BHs. Mathematical and physical features such as Killing vectors, singularities, and mass have been studied. Their horizons and thermodynamic properties have also been investigated. In addition, relationship with other related works (including McVittie's) are described.
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Stavrinos, P. C., and A. P. Kouretsis. "FRW-metric and Friedmann equations in a generalized cosmological model." Journal of Physics: Conference Series 68 (May 1, 2007): 012023. http://dx.doi.org/10.1088/1742-6596/68/1/012023.

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22

Dogan, T., and YC Park. "Testing the residential daylight score: Comparing climate-based daylighting metrics for 2444 individual dwelling units in temperate climates." Lighting Research & Technology 52, no. 8 (June 17, 2020): 991–1008. http://dx.doi.org/10.1177/1477153520924838.

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Evaluation metrics using climate-based daylight modelling paradigms have become the de-facto standard in work environments but have only limited applicability in residential architecture. Qualities of daylight cited in the architectural design literature, such as daily and seasonal availability of daylight as well as access to direct sunlight, are simulated in detail but are usually overlooked in the commonly used evaluation metrics. In a recent paper, a new climate-based, annual daylight evaluation framework called the residential daylight score has been proposed for cold and temperate climates. It assesses daylight autonomy and access to direct light in 12 daily and seasonal bins and proposes targets for seasonal and diurnal daylight autonomy and duration of direct sunlight exposure. While the metric aims to capture essential characteristics of residential daylight, only a few reference cases exist in the literature to adequately judge its achievability and applicability. This paper aims to thoroughly test the residential daylight score and provide reference cases for 2444 apartments from a set of 18 multifamily buildings that compare the new metric with currently used climate-based metrics.
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23

Grünthal, Satu. "Metre and meaning in two poems by Ilpo Tiihonen." Sign Systems Studies 40, no. 1/2 (September 1, 2012): 192–210. http://dx.doi.org/10.12697/sss.2012.1-2.10.

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Metre and meaning intertwine in manifold ways. The aim of this paper is to discuss the interplay between the metric and semantic structures in poetry in the light of the work of a Finnish poet, Ilpo Tiihonen. Throughout his career, which started in the 1970s, he has been one of the few Finnish contemporary poets to make constant use of metric structures and rhyme. The article also aims to shed some light on questions that arise when metrical poetry is translated from one language into another, in this case from Finnish into English.
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24

Reynolds, Stephanie, Therese Abrahamsson, Per Jesper Sjöström, Simon R. Schultz, and Pier Luigi Dragotti. "CosMIC: A Consistent Metric for Spike Inference from Calcium Imaging." Neural Computation 30, no. 10 (October 2018): 2726–56. http://dx.doi.org/10.1162/neco_a_01114.

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In recent years, the development of algorithms to detect neuronal spiking activity from two-photon calcium imaging data has received much attention, yet few researchers have examined the metrics used to assess the similarity of detected spike trains with the ground truth. We highlight the limitations of the two most commonly used metrics, the spike train correlation and success rate, and propose an alternative, which we refer to as CosMIC. Rather than operating on the true and estimated spike trains directly, the proposed metric assesses the similarity of the pulse trains obtained from convolution of the spike trains with a smoothing pulse. The pulse width, which is derived from the statistics of the imaging data, reflects the temporal tolerance of the metric. The final metric score is the size of the commonalities of the pulse trains as a fraction of their average size. Viewed through the lens of set theory, CosMIC resembles a continuous Sørensen-Dice coefficient—an index commonly used to assess the similarity of discrete, presence/absence data. We demonstrate the ability of the proposed metric to discriminate the precision and recall of spike train estimates. Unlike the spike train correlation, which appears to reward overestimation, the proposed metric score is maximized when the correct number of spikes have been detected. Furthermore, we show that CosMIC is more sensitive to the temporal precision of estimates than the success rate.
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Dass, B. K., Namita Sharma, and Rashmi Verma. "The packing radius of a poset block code." Discrete Mathematics, Algorithms and Applications 07, no. 04 (December 2015): 1550045. http://dx.doi.org/10.1142/s1793830915500457.

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We investigate the properties of the packing radius of a code with respect to poset block metric. In the process, we have addressed a few minor errors in the paper, “The packing radius of a code and partitioning problems: The case for poset metrics”, in Proc. IEEE Int. Symp. Information Theory (2014), pp. 2954–2958 by D’Oliveira and Firer.
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Paul, Niladri, Saikat Nil Chakrabarty, and Kaushik Bhattacharya. "Cosmological bounces in spatially flat FRW spacetimes in metricf(R) gravity." Journal of Cosmology and Astroparticle Physics 2014, no. 10 (October 6, 2014): 009. http://dx.doi.org/10.1088/1475-7516/2014/10/009.

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GHANEH, T., F. DARABI, and H. MOTAVALLI. "SIGNATURE CHANGE IN NONCOMMUTATIVE FRW COSMOLOGY." Modern Physics Letters A 27, no. 37 (November 25, 2012): 1250214. http://dx.doi.org/10.1142/s0217732312502148.

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The conditions for which the no boundary proposal may have a classical realization of a continuous change of signature, are investigated for a cosmological model described by FRW metric coupled with a self-interacting scalar field, having a noncommutative phase space of dynamical variables. The model is then quantized and a good correspondence is shown between the classical and quantum cosmology indicating that the noncommutativity does not destruct the classical-quantum correspondence. It is also shown that the quantum cosmology supports a signature transition where the bare cosmological constant takes a vast continuous spectrum of negative values. The bounds of bare cosmological constant are limited by the values of noncommutative parameters. Moreover, it turns out that the physical parameters are constrained by the noncommutativity parameters.
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Vázquez-Báez, V., and C. Ramírez. "Quantum Cosmology of Quadratic f(R) Theories with a FRW Metric." Advances in Mathematical Physics 2017 (2017): 1–5. http://dx.doi.org/10.1155/2017/1056514.

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We study the quantum cosmology of a quadratic fR theory with a FRW metric, via one of its equivalent Horndeski type actions, where the dynamic of the scalar field is induced. The classical equations of motion and the Wheeler-DeWitt equation, in their exact versions, are solved numerically. There is a free parameter in the action from which two cases follow: inflation + exit and inflation alone. The numerical solution of the Wheeler-DeWitt equation depends strongly on the boundary conditions, which can be chosen so that the resulting wave function of the universe is normalizable and consistent with Hermitian operators.
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Amine, Khalil. "An energy-degree evaluation metric for clustering purposes in mobile ad hoc networks." International Journal of Modeling, Simulation, and Scientific Computing 10, no. 02 (April 2019): 1950005. http://dx.doi.org/10.1142/s1793962319500053.

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Network clustering is the process of partitioning a network into a number of virtual entities mastered by certain nodes, called cluster centers that are responsible for collecting and maintaining topology information and managing the routing processes. In ad hoc networking, clustering has been introduced to deal with the dynamic topology by providing a temporarily stable network core. Clustering process mainly depends on the metric upon which the selection of cluster centers is performed. A wide range of clustering metrics were introduced in the literature based on network issues including mobility and connectivity degree, giving rise to a variety of clustering schemes. Although clustering provides energy consumption reduction, residual energy has not received enough attention and few studies have addressed the clustering on the basis of this feature. This paper discusses the current clustering metrics and proposes an energy-degree evaluation metric with mobility consideration taking into account the nodes residual energy and the network connectivity as two main keys of clustering.
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Chen, Guangyuan, Guoliang Lu, Zhaohong Xie, and Wei Shang. "Anomaly Detection in EEG Signals: A Case Study on Similarity Measure." Computational Intelligence and Neuroscience 2020 (January 10, 2020): 1–16. http://dx.doi.org/10.1155/2020/6925107.

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Motivation. Anomaly EEG detection is a long-standing problem in analysis of EEG signals. The basic premise of this problem is consideration of the similarity between two nonstationary EEG recordings. A well-established scheme is based on sequence matching, typically including three steps: feature extraction, similarity measure, and decision-making. Current approaches mainly focus on EEG feature extraction and decision-making, and few of them involve the similarity measure/quantification. Generally, to design an appropriate similarity metric, that is compatible with the considered problem/data, is also an important issue in the design of such detection systems. It is however impossible to directly apply those existing metrics to anomaly EEG detection without any consideration of domain specificity. Methodology. The main objective of this work is to investigate the impacts of different similarity metrics on anomaly EEG detection. A few metrics that are potentially available for the EEG analysis have been collected from other areas by a careful review of related works. The so-called power spectrum is extracted as features of EEG signals, and a null hypothesis testing is employed to make the final decision. Two indicators have been used to evaluate the detection performance. One is to reflect the level of measured similarity between two compared EEG signals, and the other is to quantify the detection accuracy. Results. Experiments were conducted on two data sets, respectively. The results demonstrate the positive impacts of different similarity metrics on anomaly EEG detection. The Hellinger distance (HD) and Bhattacharyya distance (BD) metrics show excellent performances: an accuracy of 0.9167 for our data set and an accuracy of 0.9667 for the Bern-Barcelona EEG data set. Both of HD and BD metrics are constructed based on the Bhattacharyya coefficient, implying the priority of the Bhattacharyya coefficient when dealing with the highly noisy EEG signals. In future work, we will exploit an integrated metric that combines HD and BD for the similarity measure of EEG signals.
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Schuttner, Linnaea, Ashok Reddy, Andrew A. White, Edwin S. Wong, and Joshua M. Liao. "Quality in the Context of Value: Reliability of Quality Metrics in an Academic Health System Shifting Toward Value-Based Payments." American Journal of Medical Quality 35, no. 6 (May 5, 2020): 465–73. http://dx.doi.org/10.1177/1062860620917205.

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Quality metrics are fundamental to value-based payment reforms. Because metrics are key components used to drive performance, health care organizations participating in payment reforms should consider metric reliability—a measure of true performance versus statistical “noise.” This cross-sectional study examined reliability, variation from patient and clinician characteristics, and volume thresholds for 9 ambulatory quality metrics in a health system engaged in value-based payment reforms. Hierarchical mixed models were used to analyze data from 276 316 patients attributed to 4373 clinicians in 31 primary care clinics from 2015 to 2017. Reliability was lower for all metrics at the clinician level (range 6%-64%) than at the clinic level (84%-99%), with little variation related to patient or clinician characteristics. Few clinicians, but the majority of clinics, contributed sufficient volumes of patient encounters to meet a 70% reliability threshold. These findings suggest that clinic-level performance measurement may be more appropriate than individual clinician-level measurement, particularly in low-volume contexts.
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32

THONGMAK, MATHUPAYAS, and PORNSIRI MUENCHAISRI. "MAINTAINABILITY METRICS FOR ASPECT-ORIENTED SOFTWARE." International Journal of Software Engineering and Knowledge Engineering 19, no. 03 (May 2009): 389–420. http://dx.doi.org/10.1142/s0218194009004234.

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Maintainability is an important factor that developers should be concerned because two-thirds of software costs involve maintenance. Aspect-oriented programming (AOP) paradigm is aimed to increase the software maintainability. It solves code tangling and code scattering problems by introducing a new modular unit, called "aspect". Various research works are provided to support measuring the object-oriented software, but only few studies are set up to support measuring the aspect-oriented software. This paper proposes aspect-oriented software maintainability metrics and a set of aspect-oriented design guidelines to support the metrics. By combining the proposed guidelines, object-oriented design principles, and aspect-oriented design principles, the metrics are constructed according to the Factor-Strategy (FS) quality model and the Factor-Criteria-Metric (FCM) quality model. Principle violation check definitions in the form of Boolean expressions are also defined to conduct software measurement and to fulfill the metrics. Finally, the aspect-oriented software maintainability metrics are applied to detect design principle violations in fifty AspectJ systems. The results show that for all systems their hidden flaws are exposed. Moreover, the proposed metrics are used to compare the maintainability between two versions of systems written in Java and AspectJ.
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33

KIM, WONTAE, YOUNG-JAI PARK, and MYUNGSEOK YOON. "ENTROPY OF THE FRW UNIVERSE BASED ON THE GENERALIZED UNCERTAINTY PRINCIPLE." Modern Physics Letters A 25, no. 15 (May 20, 2010): 1267–74. http://dx.doi.org/10.1142/s0217732310033049.

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The statistical entropy of the FRW universe described by time-dependent metric is newly calculated using the brick wall method based on the general uncertainty principle with the minimal length. We can determine the minimal length with the Planck scale to obtain the entropy proportional to the area of the cosmological apparent horizon.
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34

SHARMA, S. K., and U. KHANAL. "PERTURBATION OF FRW SPACETIME IN NP FORMALISM." International Journal of Modern Physics D 23, no. 02 (January 29, 2014): 1450017. http://dx.doi.org/10.1142/s0218271814500175.

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Jacobi polynomials appear to play a very important role in describing all the spin field (s = 0, 1/2, 1, 2) perturbation of the Friedmann–Robertson–Walker (FRW) spacetime. The formulation becomes very transparent when done in Newman–Penrose (NP) formalism. All the variables are separable, and the spatial eigenfunctions turn out to be Jacobian polynomials in different forms. In particular, the angular ones are expressible as spin weighted spherical harmonics which are just the spherical harmonics formed with Jacobi polynomials. The radial eigenfunctions are also Jacobi polynomials but with unconventional parameters. Various properties of these polynomials are used to describe the scalar, vector and tensor modes of the perturbation. The Green's function of the scalar perturbations and also its Lienard–Wiechert type potentials are derived, and are shown to reduce to the familiar ones in the limit to flat FRW case. Some of the components of the perturbed metric tensor hμν have also been calculated.
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35

Djordjevic, Goran S., Ljubisa Nesic, and Darko Radovancevic. "Signature change in p-adic and noncommutative FRW cosmology." International Journal of Modern Physics A 29, no. 27 (October 28, 2014): 1450155. http://dx.doi.org/10.1142/s0217751x14501553.

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The significant matter for the construction of the so-called no-boundary proposal is the assumption of signature transition, which has been a way to deal with the problem of initial conditions of the universe. On the other hand, results of Loop Quantum Gravity indicate that the signature change is related to the discrete nature of space at the Planck scale. Motivated by possibility of non-Archimedean and/or noncommutative structure of space–time at the Planck scale, in this work we consider the classical, p-adic and (spatial) noncommutative form of a cosmological model with Friedmann–Robertson–Walker (FRW) metric coupled with a self-interacting scalar field.
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36

Zahedi Nooghabi, Mahdi, and Akram Fathian Dastgerdi. "Proposed metrics for data accessibility in the context of linked open data." Program 50, no. 2 (April 4, 2016): 184–94. http://dx.doi.org/10.1108/prog-01-2015-0007.

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Purpose – One of the most important categories in linked open data (LOD) quality models is “data accessibility.” The purpose of this paper is to propose some metrics and indicators for assessing data accessibility in LOD and the semantic web context. Design/methodology/approach – In this paper, at first the authors consider some data quality and LOD quality models to review proposed subcategories for data accessibility dimension in related texts. Then, based on goal question metric (GQM) approach, the authors specify the project goals, main issues and some questions. Finally, the authors propose some metrics for assessing the data accessibility in the context of the semantic web. Findings – Based on GQM approach, the authors determined three main issues for data accessibility, including data availability, data performance, and data security policy. Then the authors created four main questions related to these issues. As a conclusion, the authors proposed 27 metrics for measuring these questions. Originality/value – Nowadays, one of the main challenges regarding data quality is the lack of agreement on widespread quality metrics and practical instruments for evaluating quality. Accessibility is an important aspect of data quality. However, few researches have been done to provide metrics and indicators for assessing data accessibility in the context of the semantic web. So, in this research, the authors consider the data accessibility dimension and propose a comparatively comprehensive set of metrics.
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37

Waugh, D. W., K. M. Grise, W. J. M. Seviour, S. M. Davis, N. Davis, O. Adam, S. W. Son, et al. "Revisiting the Relationship among Metrics of Tropical Expansion." Journal of Climate 31, no. 18 (September 2018): 7565–81. http://dx.doi.org/10.1175/jcli-d-18-0108.1.

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There is mounting evidence that the width of the tropics has increased over the last few decades, but there are large differences in reported expansion rates. This is, likely, in part due to the wide variety of metrics that have been used to define the tropical width. Here we perform a systematic investigation into the relationship among nine metrics of the zonal-mean tropical width using preindustrial control and abrupt quadrupling of CO2 simulations from a suite of coupled climate models. It is shown that the latitudes of the edge of the Hadley cell, the midlatitude eddy-driven jet, the edge of the subtropical dry zones, and the Southern Hemisphere subtropical high covary interannually and exhibit similar long-term responses to a quadrupling of CO2. However, metrics based on the outgoing longwave radiation, the position of the subtropical jet, the break in the tropopause, and the Northern Hemisphere subtropical high have very weak covariations with the above metrics and/or respond differently to increases in CO2 and thus are not good indicators of the expansion of the Hadley cell or subtropical dry zone. The differing variability and responses to increases in CO2 among metrics highlights that care is needed when choosing metrics for studies of the width of the tropics and that it is important to make sure the metric used is appropriate for the specific phenomena and impacts being examined.
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38

LA CAMERA, M. "TIME-DEPENDENT EXTRA DIMENSION AND HIGHER-DIMENSIONAL MODIFICATIONS TO THE MATTER CONTENT IN FRW SPACETIMES." Modern Physics Letters A 25, no. 10 (March 28, 2010): 781–92. http://dx.doi.org/10.1142/s021773231003286x.

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In this work we suggest that higher-dimensional modifications to the matter content in FRW spacetimes can be obtained not only, as first considered by Ponce de Leon, referring to "moving" 4D hypersurfaces non-orthogonal to the time-dependent extra dimension of an embedding 5D manifold, but also referring to "fixed" 4D hypersurfaces orthogonal to a suitable scalar function which defines a static foliation of the 5D manifold and takes the role of the extra dimension in a suitable coordinate system. Results obtained in each approach crucially depend on the method used to identify the 4D metric of our brane universe from the 5D metric of the bulk manifold.
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39

Berman, Ethan E., Tabitha A. Graves, Nate L. Mikle, Jerod A. Merkle, Aaron N. Johnston, and Geneva W. Chong. "Comparative Quality and Trend of Remotely Sensed Phenology and Productivity Metrics across the Western United States." Remote Sensing 12, no. 16 (August 7, 2020): 2538. http://dx.doi.org/10.3390/rs12162538.

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Vegetation phenology and productivity play a crucial role in surface energy balance, plant and animal distribution, and animal movement and habitat use and can be measured with remote sensing metrics including start of season (SOS), peak instantaneous rate of green-up date (PIRGd), peak of season (POS), end of season (EOS), and integrated vegetation indices. However, for most metrics, we do not yet understand the agreement of remotely sensed data products with near-surface observations. We also need summaries of changes over time, spatial distribution, variability, and consistency in remote sensing dataset metrics for vegetation timing and quality. We compare metrics from 10 leading remote sensing datasets against a network of PhenoCam near-surface cameras throughout the western United States from 2002 to 2014. Most phenology metrics representing a date (SOS, PIRGd, POS, and EOS), rather than a duration (length of spring, length of growing season), better agreed with near-surface metrics but results varied by dataset, metric, and land cover, with absolute value of mean bias ranging from 0.38 (PIRGd) to 37.92 days (EOS). Datasets had higher agreement with PhenoCam metrics in shrublands, grasslands, and deciduous forests than in evergreen forests. Phenology metrics had higher agreement than productivity metrics, aside from a few datasets in deciduous forests. Using two datasets covering the period 1982–2016 that best agreed with PhenoCam metrics, we analyzed changes over time to growing seasons. Both datasets exhibited substantial spatial heterogeneity in the direction of phenology trends. Variability of metrics increased over time in some areas, particularly in the Southwest. Approximately 60% of pixels had consistent trend direction between datasets for SOS, POS, and EOS, with the direction varying by location. In all ecoregions except Mediterranean California, EOS has become later. This study comprehensively compares remote sensing datasets across multiple growing season metrics and discusses considerations for applied users to inform their data choices.
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40

Zhang, Pei, Yunpeng Bai, Dong Wang, Bendu Bai, and Ying Li. "Few-Shot Classification of Aerial Scene Images via Meta-Learning." Remote Sensing 13, no. 1 (December 31, 2020): 108. http://dx.doi.org/10.3390/rs13010108.

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Convolutional neural network (CNN) based methods have dominated the field of aerial scene classification for the past few years. While achieving remarkable success, CNN-based methods suffer from excessive parameters and notoriously rely on large amounts of training data. In this work, we introduce few-shot learning to the aerial scene classification problem. Few-shot learning aims to learn a model on base-set that can quickly adapt to unseen categories in novel-set, using only a few labeled samples. To this end, we proposed a meta-learning method for few-shot classification of aerial scene images. First, we train a feature extractor on all base categories to learn a representation of inputs. Then in the meta-training stage, the classifier is optimized in the metric space by cosine distance with a learnable scale parameter. At last, in the meta-testing stage, the query sample in the unseen category is predicted by the adapted classifier given a few support samples. We conduct extensive experiments on two challenging datasets: NWPU-RESISC45 and RSD46-WHU. The experimental results show that our method yields state-of-the-art performance. Furthermore, several ablation experiments are conducted to investigate the effects of dataset scale, the impact of different metrics and the number of support shots; the experiment results confirm that our model is specifically effective in few-shot settings.
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41

Kosinski, Karen Claire, Alexandra V. Kulinkina, David Tybor, Dickson Osabutey, Kwabena M. Bosompem, and Elena N. Naumova. "Agreement among Four Prevalence Metrics for Urogenital Schistosomiasis in the Eastern Region of Ghana." BioMed Research International 2016 (2016): 1–11. http://dx.doi.org/10.1155/2016/7627358.

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Few studies assess agreement amongSchistosoma haematobiumeggs, measured hematuria, and self-reported metrics. We assessed agreement among four metrics at a single time point and analyzed the stability of infection across two time points with a single metric. We used data from the Eastern Region of Ghana and constructed logistic regression models. Girls reporting macrohematuria were 4.1 times more likely to have measured hematuria than girls not reporting macrohematuria (CI95%: 2.1–7.9); girls who swim were 3.6 times more likely to have measured hematuria than nonswimmers (CI95%: 1.6–7.9). For boys, neither self-reported metric was predictive. Girls with measured hematuria in 2010 were 3.3 times more likely to be positive in 2012 (CI95%: 1.01–10.5), but boys showed no association. Boys with measured hematuria in 2008 were 6.0 times more likely to have measured hematuria in 2009 (CI95%: 1.5–23.9) and those with eggs in urine in 2008 were 4.8 times more likely to have eggs in urine in 2009 (CI95%: 1.2–18.8). For girls, measured hematuria in 2008 predicted a positive test in 2009 (OR = 2.8; CI95%: 1.1–6.8), but egg status did not. Agreement between dipstick results and eggs suggests continued dipstick used is appropriate. Self-reported swimming should be further examined. For effective disease monitoring, we recommend annual dipstick testing.
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42

Bergeron, Jean, Robert Leconte, Mélanie Trudel, and Sepehr Farhoodi. "On the Choice of Metric to Calibrate Time-Invariant Ensemble Kalman Filter Hyper-Parameters for Discharge Data Assimilation and Its Impact on Discharge Forecast Modelling." Hydrology 8, no. 1 (February 24, 2021): 36. http://dx.doi.org/10.3390/hydrology8010036.

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An important step when using some data assimilation methods, such as the ensemble Kalman filter and its variants, is to calibrate its parameters. Also called hyper-parameters, these include the model and observation errors, which have previously been shown to have a strong impact on the performance of the data assimilation method. Many metrics can be used to calibrate these hyper-parameters but may not all yield the same optimal set of values. The current study investigated the importance of the choice of metric used during the hyper-parameter calibration phase and its impact on discharge forecasts. The types of metrics used each focused on discharge accuracy, ensemble spread or observation-minus-background statistics. The calibration was performed for the ensemble square root Kalman filter over two catchments in Canada using two different hydrologic models per catchment. Results show that the optimal set of hyper-parameters depended heavily on the choice of metric used during the calibration phase, where data assimilation was applied. These sets of hyper-parameters in turn produced different hydrologic forecasts. This influence was reduced as the forecast lead time increased, because of not applying data assimilation in the forecast mode, and accordingly, convergence of model state ensembles produced in the calibration phase. However, the influence could remain considerable for a few days up to multiple weeks depending on the catchment and the model. As such, a preliminary analysis would be recommended for future studies to better understand the impact that metrics can have within and outside the bounds of hyper-parameter calibration.
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43

Yılmaz, Nejat Tevfik. "Effective fluid FLRW cosmologies of minimal massive gravity." Modern Physics Letters A 30, no. 18 (May 25, 2015): 1550087. http://dx.doi.org/10.1142/s021773231550087x.

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By using a solution ansatz we partially decouple the metric and the Stückelberg sectors of the minimal massive gravity (MMGR). In this scheme for a diagonal physical metric we find the general solutions for the scalars of the theory and the particular fiducial (background) metric which leads to these solutions. Then we adopt this general formalism to construct the derivation of new Friedmann–Lemaitre–Robertson–Walker (FLRW) cosmologies of the theory in the presence of a so-called effective ideal fluid which arises from our solution ansatz as a modifying, non-physical source for the Einstein and the corresponding Friedmann equations.
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44

Tripp-Barba, Carolina, Aníbal Zaldívar-Colado, Luis Urquiza-Aguiar, and José Alfonso Aguilar-Calderón. "Survey on Routing Protocols for Vehicular Ad Hoc Networks Based on Multimetrics." Electronics 8, no. 10 (October 17, 2019): 1177. http://dx.doi.org/10.3390/electronics8101177.

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In the last few years, many routing protocols have been proposed for vehicular ad hoc networks (VANETs) because of their specific characteristics. Protocols that use several metrics have been shown to be the most adequate to VANETs due to their effectiveness in dealing with dynamic environment changes due to vehicle mobility. Metrics such as distance, density, link stability, speed, and position were selected by the authors for the best proposal. Several surveys of routing proposals have been generated to categorize contributions and their application scenarios, but none of them focused on multimetric approaches. In this paper, we present a review of the routing protocols based on more than one metric to select the best route in a VANET. The main objective of this research was to present the contemporary most frequently used metrics in the different proposals and their application scenarios. This review helps in the selection protocols or the creation of metrics when a new protocol is designed.This survey of multimetric VANET routing protocols employed systematic literature-review (SLR) methodology in four well-knownown databases that allowed to analyze current state-of-the-art proposals. In addition, this paper provides a description of these multimetric routing protocols. Our findings indicate that distance and speed are the most popular and versatile metrics. Finally, we define some possible directions for future research related to the use of this class of protocols.
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45

Li, Xiaomeng, Lequan Yu, Chi-Wing Fu, Meng Fang, and Pheng-Ann Heng. "Revisiting metric learning for few-shot image classification." Neurocomputing 406 (September 2020): 49–58. http://dx.doi.org/10.1016/j.neucom.2020.04.040.

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46

Melia, Fulvio. "Proper size of the visible Universe in FRW metrics with a constant spacetime curvature." Classical and Quantum Gravity 30, no. 15 (June 25, 2013): 155007. http://dx.doi.org/10.1088/0264-9381/30/15/155007.

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47

SINGH, C. P. "VISCOUS FRW MODELS WITH PARTICLE CREATION IN EARLY UNIVERSE." Modern Physics Letters A 27, no. 12 (April 20, 2012): 1250070. http://dx.doi.org/10.1142/s0217732312500708.

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We discuss the dynamical effects of bulk viscosity and particle creation on the early evolution of the Friedmann–Robertson–Walker model in the framework of open thermodynamical systems. We consider bulk viscosity and particle creation as separate irreversible processes. Exact solutions of the Einstein field equations are obtained by using the "gamma-law" equation of state p = (γ-1)ρ, where the adiabatic parameter γ varies with scale factor of the metric. We consider the cosmological model to study the early phases of the evolution of the universe as it goes from an inflationary phase to a radiation-dominated era in the presence of bulk viscosity and particle creation. Analytical solutions are obtained for particle number density and entropy for all models. It is found that, by choosing appropriate functions for particle creation rate and bulk viscous coefficient, the models exhibit singular and non-singular beginnings.
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48

Halpern, Michael T., Hamlet Gasoyan, and William E. Aaronson. "Metrics to evaluate the performance of cancer center leadership." Journal of Clinical Oncology 37, no. 27_suppl (September 20, 2019): 10. http://dx.doi.org/10.1200/jco.2019.37.27_suppl.10.

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10 Background: Cancer centers are diverse health care organizations that involve clinicians and researchers focused on understanding, treating, and controlling cancer in the populations they serve. While there are many metrics used to evaluate cancer center performance, few standardized measures have been identified to evaluate the performance of cancer center leadership. The goal of this manuscript is to systematically identify, compare, and categorize metrics used to evaluate the leadership of U.S. cancer centers. Methods: We performed a structured, systematic electronic search of peer-reviewed journals using Medline to identify English language articles discussing metrics used to evaluate cancer center leadership. Identified studies were reviewed by two independent reviewers to determine appropriateness for inclusion. Metrics were classified using ten a priori-defined categories of evaluation for data abstraction. Results: We included 34 manuscripts in this review. The most commonly-discussed evaluation metric category is organizational strategy/planning (31 of the 34 papers), followed by leader characteristics (25 papers), clinical performance (21), and facility characteristics (20). Organizational strategy/planning include governance structure; strategic development; quality assurance/improvement; mission/vision; business planning; and program development. Leader characteristic metrics include communication; vision/strategic thinking; personal skills; team coordination; leadership style; and staff development. Clinical Performance metrics focus on delivery of and outcomes from clinical services while facility characteristics include space allocation and access to support services. Conclusions: The metrics reviewed and synthesized in this report may be considered measurable outcomes to evaluate whether cancer center leadership demonstrates key competencies. Additional research is needed to explore the link between metrics used to evaluate cancer center leaders, the desired competencies for healthcare leaders, and objective measures of whether a cancer center is “successful”.
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49

M., Manoj H., and Nandakumar A. N. "Constructing Relationship between Software Metrics and Code Reusability in Object Oriented Design." APTIKOM Journal on Computer Science and Information Technologies 1, no. 2 (May 8, 2016): 63–76. http://dx.doi.org/10.34306/csit.v1i2.49.

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The role of design pattern in the form of software metric and internal code architecture for object-oriented design plays a critical role in software en-gineering in terms of production cost efficiency. This paper discusses about code reusability that is a frequently exercised cost saving methodology in IT produc-tion. After reviewing existing literatures towards study on software metrics, we found that very few studies are witnessed to incline towards code reusability. Hence, we developed a simple analytical model that establishes relationship between the design components of standard software metric and code reusability using case studies of three software projects (Customer Relationship Management project, Supply Chain Management project, and Enterprise Relationship Management project). We also testify our proposal using stochastic based Markov model to find that proposed system can extract significant information of maximized values of code reusability with increasing level of uncertainties of software project methodologies.
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50

M., Manoj H., and Nandakumar A. N. "Constructing Relationship between Software Metrics and Code Reusability in Object Oriented Design." APTIKOM Journal on Computer Science and Information Technologies 1, no. 2 (July 1, 2016): 63–76. http://dx.doi.org/10.11591/aptikom.j.csit.112.

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The role of design pattern in the form of software metric and internal code architecture for object-oriented design plays a critical role in software en-gineering in terms of production cost efficiency. This paper discusses about code reusability that is a frequently exercised cost saving methodology in IT produc-tion. After reviewing existing literatures towards study on software metrics, we found that very few studies are witnessed to incline towards code reusability. Hence, we developed a simple analytical model that establishes relationship between the design components of standard software metric and code reusability using case studies of three software projects (Customer Relationship Management project, Supply Chain Management project, and Enterprise Relationship Management project). We also testify our proposal using stochastic based Markov model to find that proposed system can extract significant information of maximized values of code reusability with increasing level of uncertainties of software project methodologies.
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