relative size
Recently Published Documents


TOTAL DOCUMENTS

1336
(FIVE YEARS 432)

H-INDEX

61
(FIVE YEARS 10)

2022 ◽  
Vol 25 (1) ◽  
pp. 1-25
Author(s):  
Sibghat Ullah Bazai ◽  
Julian Jang-Jaccard ◽  
Hooman Alavizadeh

Multi-dimensional data anonymization approaches (e.g., Mondrian) ensure more fine-grained data privacy by providing a different anonymization strategy applied for each attribute. Many variations of multi-dimensional anonymization have been implemented on different distributed processing platforms (e.g., MapReduce, Spark) to take advantage of their scalability and parallelism supports. According to our critical analysis on overheads, either existing iteration-based or recursion-based approaches do not provide effective mechanisms for creating the optimal number of and relative size of resilient distributed datasets (RDDs), thus heavily suffer from performance overheads. To solve this issue, we propose a novel hybrid approach for effectively implementing a multi-dimensional data anonymization strategy (e.g., Mondrian) that is scalable and provides high-performance. Our hybrid approach provides a mechanism to create far fewer RDDs and smaller size partitions attached to each RDD than existing approaches. This optimal RDD creation and operations approach is critical for many multi-dimensional data anonymization applications that create tremendous execution complexity. The new mechanism in our proposed hybrid approach can dramatically reduce the critical overheads involved in re-computation cost, shuffle operations, message exchange, and cache management.


2022 ◽  
Author(s):  
Cedric Mariac ◽  
Kevin Bethune ◽  
Sinara Oliveira de Aquino ◽  
Mohamed Abdelrahman ◽  
Adeline Barnaud ◽  
...  

In-solution based capture is becoming a method of choice for sequencing targeted sequence. We assessed and optimized a capture protocol in 20 different species from 6 different plant genus using kits from 20,000 to 200,000 baits targeting from 300 to 32,000 genes. We evaluated both the effectiveness of the capture protocol and the fold enrichment in targeted sequences. We proposed a protocol with multiplexing up to 96 samples in a single hybridization and showed it was an efficient and cost-effective strategy. We also extended the use of capture to pools of 100 samples and proved the efficiency of the method to assess allele frequency. Using a set of various organisms with different genome sizes, we demonstrated a correlation between the percentage of on-target reads vs. the relative size of the targeted sequences. Altogether, we proposed methods, strategies, cost-efficient protocols and statistics to better evaluate and more effectively use hybridization capture.


2022 ◽  
Vol 8 ◽  
Author(s):  
Vanda Brotas ◽  
Glen A. Tarran ◽  
Vera Veloso ◽  
Robert J. W. Brewin ◽  
E. Malcolm S. Woodward ◽  
...  

Phytoplankton biomass, through its proxy, Chlorophyll a, has been assessed at synoptic temporal and spatial scales with satellite remote sensing (RS) for over two decades. Also, RS algorithms to monitor relative size classes abundance are widely used; however, differentiating functional types from RS, as well as the assessment of phytoplankton structure, in terms of carbon remains a challenge. Hence, the main motivation of this work it to discuss the links between size classes and phytoplankton groups, in order to foster the capability of assessing phytoplankton community structure and phytoplankton size fractionated carbon budgets. To accomplish our goal, we used data (on nutrients, photosynthetic pigments concentration and cell numbers per taxa) collected in surface samples along a transect on the Atlantic Ocean, during the 25th Atlantic Meridional Transect cruise (AMT25) between 50° N and 50° S, from nutrient-rich high latitudes to the oligotrophic gyres. We compared phytoplankton size classes from two methodological approaches: (i) using the concentration of diagnostic photosynthetic pigments, and assessing the abundance of the three size classes, micro-, nano-, and picoplankton, and (ii) identifying and enumerating phytoplankton taxa by microscopy or by flow cytometry, converting into carbon, and dividing the community into five size classes, according to their cell carbon content. The distribution of phytoplankton community in the different oceanographic regions is presented in terms of size classes, taxonomic groups and functional types, and discussed in relation to the environmental oceanographic conditions. The distribution of seven functional types along the transect showed the dominance of picoautotrophs in the Atlantic gyres and high biomass of diatoms and autotrophic dinoflagellates (ADinos) in higher northern and southern latitudes, where larger cells constituted the major component of the biomass. Total carbon ranged from 65 to 4 mg carbon m–3, at latitudes 45° S and 27° N, respectively. The pigment and cell carbon approaches gave good consistency for picoplankton and microplankton size classes, but nanoplankton size class was overestimated by the pigment-based approach. The limitation of enumerating methods to accurately resolve cells between 5 and 10 μm might be cause of this mismatch, and is highlighted as a knowledge gap. Finally, the three-component model of Brewin et al. was fitted to the Chlorophyll a (Chla) data and, for the first time, to the carbon data, to extract the biomass of three size classes of phytoplankton. The general pattern of the model fitted to the carbon data was in accordance with the fits to Chla data. The ratio of the parameter representing the asymptotic maximum biomass gave reasonable values for Carbon:Chla ratios, with an overall median of 112, but with higher values for picoplankton (170) than for combined pico-nanoplankton (36). The approach may be useful for inferring size-fractionated carbon from Earth Observation.


2022 ◽  
Vol 10 (1) ◽  
pp. 57-70 ◽  
Author(s):  
Rajendra K. Choubey ◽  
Shailendra Kumar

Polynomial equations in non-dimensional form for various fracture parameters of double-K fracture model for compact tension specimen have been derived and presented in this paper. These equations can be used for computing different double-K fracture parameters of concrete for known material properties and specimen size having relative size of initial crack length of 0.3 without involving much complexity in numerical computations. Values of peak load and corresponding crack opening displacement as necessary to compute the double-K fracture parameters of concrete have been derived from the established fictitious crack model in the present study. A simplified equation in non-dimensional form between peak load and critical crack opening displacement as obtained from a fictitious crack model has also been presented.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Koji Domon

Abstract Content industries have several profit sources that positively interact with one another, and piracy affects them not only negatively but also positively. For copyright holders, choosing to allow piracy depends upon its total external effects. This paper proves that in such case the profit function is convex with respect to the level of enforcement. This paper shows a convex profit function with respect to the level of enforcement. The convexity leads to a corner solution of optimal enforcement for copyright holders. Which corner solution is selected depends on the relative size of the sub-market, and no enforcement is profitable if the submarket size is relatively large. This result compensates for a shortcoming of discussions that assume only two options regarding the level of enforcement, zero or perfect enforcement.


Author(s):  
Lachie Scarsbrook ◽  
Alexander Verry ◽  
Kerry Walton ◽  
Rodney Hitchmough ◽  
Nic Rawlence

Methodological and technological improvements are continually revolutionizing the field of ancient DNA. Most ancient DNA extraction methods require the partial (or complete) destruction of finite museum specimens, which disproportionately impacts small or fragmentary subfossil remains, and future analyses. We present a minimally destructive ancient DNA extraction method optimized for small vertebrate remains. We applied these methods to detect lost mainland genetic diversity in the large New Zealand diplodactylid gecko genus Hoplodactylus, which is presently restricted to predator-free island sanctuaries. We present the first mitochondrial genomes for New Zealand diplodactylid geckos, recovered from 19 modern, six historic/archival (1898 to 2011) and 16 Holocene Hoplodactylus duvaucelii sensu latu specimens, and one modern Woodworthia sp. specimen. No obvious damage was observed in post-extraction micro-CT reconstructions. All ‘large gecko’ specimens examined from extinct populations were found to be conspecific with extant Hoplodactylus species, suggesting their large relative size evolved only once in the New Zealand diplodactylid radiation. Phylogenetic analyses of Hoplodactylus samples recovered two genetically (and morphologically) distinct North and South Island clades, probably corresponding to distinct species. Finer phylogeographic structuring within Hoplodactylus spp. highlighted the impacts of Late-Cenozoic biogeographic barriers, including the opening and closure of Pliocene marine straits, fluctuations in size and suitability of glacial refugia, and eustatic sea-level change. Recent mainland extinction obscured these signals from the modern tissue derived data. These results highlight the utility of minimally destructive DNA extraction in genomic analyses of less well studied small vertebrate taxa, and the conservation of natural history collections.


Author(s):  
Kateryna Deineka ◽  
Yurii Naumenko ◽  
Tamara Myronenko

The influence of the filling degree of the drum chamber on the bifurcation value of the Froude number in the case of self-excitation of self-oscillations of a two-fraction granular charge with a minimum swing is considered. Such a pulsating mode of the charge movement is used in the self-oscillating grinding process in a tumbling mill. The coarse fraction that simulated the milling bodies consisted of spherical particles of an incoherent granular material with a relative size in the chamber ψb=0.00733. The fine fraction, simulating the material to be ground, was cement with a relative particle size ψm≈0.092∙10-3. The value of the adopted analogue of the kinematic viscosity of the two-fraction granular loading approached the value of 10-3 m2/s. The main variable factor in experimental studies was the filling degree of the drum chamber with loading at rest κb=0.25, 0.35, and 0.45. An additional factor was the degree of filling the gaps between the spherical particles of the coarse fraction with particles of the fine fraction κb=0, 0.25, 0.5, and 1. The method of visual analysis through the transparent end wall of the chamber of transient processes of the loading behavior with a smooth change and fixation of the velocity was applied. The bifurcation minimum value of the rotation speed was recorded, at which the steady-state circulation mode of the load movement turns into a transient pulsation one with a minimum swing. A decrease in the bifurcation values of the Froude number Frb on the cylindrical surface of the chamber with an increase in κb has been established. An increase in the intensity of the decrease in Frb with an increase in κm was revealed. The recorded effect is due to an increase in the connected properties of a two-fraction loading during self-excitation of self-excited oscillations with an increase in κb and κm. The numerical values of the boundaries of the range of bifurcation values of the Froude number for a tumbling mill Frb=0.0484–1.17 have been determined. The obtained Frb range corresponds to the Reynolds value in the range Re=40–197. The maximum Frb value is obtained with coarse grinding. An increase in the likelihood of self-excitation of self-oscillations of the intra-chamber loading with a decrease in the fineness of grinding was revealed


2021 ◽  
pp. 014920632110638
Author(s):  
Songcui Hu ◽  
Richard J. Gentry ◽  
Timothy J. Quigley ◽  
Steven Boivie

The Behavioral Theory of the Firm suggests that performance below an aspiration triggers problemistic search that can lead to organizational change and risk-taking. This compelling perspective has spawned considerable empirical examination of diverse strategic outcomes as firms’ responses to performance feedback. However, empirical studies have provided inconsistent evidence of problemistic search effects on various organizational search outcomes. This empirical controversy is likely attributed to the fact that most research has considered problemistic search as a firm-level and relatively routinized process with a high degree of automaticity in firms’ responses to performance feedback while overlooking the role of managerial agency. Rather than viewing problemistic search as an automatic firm-level process, we believe that behavioral responses are shaped, at least partially, by top executives, notably CEOs. To this end, we first examine whether problemistic search effects vary across a range of organizational change and risk outcomes. We then explore whether the relative size of firm and CEO effects varies across different search outcomes. Using a multilevel approach, we show not only the heterogeneity in problemistic search effects on different organizational outcomes but also heterogeneity in the relative size of firm and CEO effects on these outcomes. While firm effects are substantial in directing some strategic decisions, as proposed by the problemistic search model, CEO effects are large for certain organizational outcomes, such as changes in resource allocation. This study serves as a jumping-off point for future theorizing and empirical work on problemistic search that incorporate the role of managerial agency.


2021 ◽  
Author(s):  
Joshua Eykens ◽  
Raf Guns ◽  
Raf Vanderstraeten

In this study we explore the disciplinary diversity present within subject specialties in the social sciences and humanities. Subject specialties are operationalized as textually coherent clusters of documents. We apply topic modelling to textual information on the individual document level (titles and abstracts) to cluster a multilingual set of roughly 45,000 documents into subject specialties. The dataset includes the metadata of journal articles, conference proceedings, book chapters, and monographs. We make use of two indicators, namely, the organizational affiliation based on the departmental address of the authors and the cognitive orientation based on the disciplinary classifications at the publication level. First, we study the disciplinary diversity of the clusters by calculating a Hill-type diversity index. We draw an overall picture of the distribution of subject specialties over diversity scores and contrast the two indicators with each other. The goal is to discover whether some subject specialties are inherently multi- or interdisciplinary in nature, and whether the different indicators are telling a well-aligned, similar story. Second, for each cluster of documents we calculate the dominance, i.e. the relative size of the largest discipline. This proxy of disciplinary concentration gives an idea of the extent to which a specialty is disciplined. The results show that all subject specialties analyzed serve as interdisciplinary trading grounds, with outliers in both directions of the disciplinary-interdisciplinary continuum. For a large share of specialties, the dominant cognitive and organizational disciplinary classification were found to be well aligned. We present a typology of subject specialties by contrasting the organizational and cognitive diversity scores.


Animals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3541
Author(s):  
Reuven Yosef ◽  
Michal Korkos ◽  
Jakub Z. Kosicki

Display, wherein males attempt to maximize fitness by attracting sexually mature females to mate, is known to drive speciation by Sexual Selection. We researched the Red Sea Ghost Crab (Ocypode saratan; RSGC), in which males build display pyramids to attract females. The study was conducted at the beach in Eilat, Israel. At each session, we measured the height (in cm) of all pyramids and the dimensions (height, breadth; in cm) of the burrow entrance. We assumed that the size of the entrance represented the relative size of the carapace width of the occupant. The mean (± SE) entrance volume was 230.8 ± 11.7 cm, and the height of the pyramid was 11.8 ± 0.49 cm (n = 54). The results of our study did not support our hypothesis because we had expected to find a linear correlation between body size and pyramid height, i.e., the larger the male, the larger the pyramid. However, our results show that the largest males in the population either built small pyramids or not at all, and the cut-off of the larger crab’s body size appears to be around 350 cm3. We discovered a step-wise function in the data in that crabs with the smallest body size of ca. 250 cm3 constructed the highest pyramids, with a declining tendency between 250–350 cm3 and extremely low pyramids beyond 350 cm3. However, our findings need to be further studied with a stress on the ambiance and elucidate whether the habitats differ in temperature, humidity, prey-base, etc., before concluding as to why the larger males desist from building pyramids. This study underwrites the importance of studying the mating systems of the macro-fauna of the beaches that are fast disappearing owing to anthropogenic development.


Sign in / Sign up

Export Citation Format

Share Document