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Academic literature on the topic 'Features variability'

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Published: 9 March 2023
Last updated: 10 March 2023

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Journal articles on the topic "Features variability"

1

ADGER, DAVID. "Combinatorial Variability." Journal of Linguistics 42, no. 3 (October 13, 2006): 503–30. http://dx.doi.org/10.1017/s002222670600418x.

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The purpose of this paper is to provide a plausibility argument for a new way of thinking about intra-personal morphosyntactic variation. The idea is embedded within the framework of the Minimalist Program, and makes use of notions of feature interpretability and feature checking. Specifically, I argue that underspecification of uninterpretable features in a matching relation with interpretable features allows us to model categoricality and variability within a single system. Unlike many current approaches to intra-personal variation (which involve multiple grammars or building stochastic weightings into the grammar itself), the system attempts to predict (rather than capture) frequencies of variants. It does this by combining an evaluation metric for the acquisition of uninterpretable features with the standard properties of features and syntactic operations in the Minimalist framework. The argument is made through a case study of was/were variation in a Scottish dialect.
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Onimisi Yahaya, Mohammed. "On the Problem of Features Variability in Sequence Learning Problems." International Journal of Future Computer and Communication 4, no. 2 (April 2015): 88–92. http://dx.doi.org/10.7763/ijfcc.2015.v4.362.

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3

Ni, Zhiqiang, Fangmin Sun, and Ye Li. "Heart Rate Variability-Based Subjective Physical Fatigue Assessment." Sensors 22, no. 9 (April 21, 2022): 3199. http://dx.doi.org/10.3390/s22093199.

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Accurate assessment of physical fatigue is crucial to preventing physical injury caused by excessive exercise, overtraining during daily exercise and professional sports training. However, as a subjective feeling of an individual, physical fatigue is difficult for others to objectively evaluate. Heart rate variability (HRV), which is derived from electrocardiograms (ECG) and controlled by the autonomic nervous system, has been demonstrated to be a promising indicator for physical fatigue estimation. In this paper, we propose a novel method for the automatic and objective classification of physical fatigue based on HRV. First, a total of 24 HRV features were calculated. Then, a feature selection method was proposed to remove useless features that have a low correlation with physical fatigue and redundant features that have a high correlation with the selected features. After feature selection, the best 11 features were selected and were finally used for physical fatigue classifying. Four machine learning algorithms were trained to classify fatigue using the selected features. The experimental results indicate that the model trained using the selected 11 features could classify physical fatigue with high accuracy. More importantly, these selected features could provide important information regarding the identification of physical fatigue.
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Yasyukevich, Anna. "Features of short-period variability of total electron content at high and middle latitudes." Solar-Terrestrial Physics 7, no. 4 (December 20, 2021): 71–78. http://dx.doi.org/10.12737/stp-74202107.

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The study presents the results of comparative analysis of features of a short-period (with periods of internal gravity waves) variability of total electron content (TEC) in the ionosphere at middle (Novosibirsk) and high (Norilsk) latitudes over a long period of time (2003–2020). The period analyzed makes it possible to estimate not only diurnal and seasonal variations in the variability, but also its changes within the solar activity cycle. The level of TEC variability is shown to experience pronounced seasonal variations with maxima in winter months. The difference between the level of variability in winter and summer is about two times for Novosibirsk and up to seven times for Norilsk. The variability features a distinct diurnal variation; however, the diurnal dependence at the mid- and high-latitude stations differs significantly. At high latitudes, the level of variability in the winter period strictly depends on solar activity. For the mid-latitude station, there is no clear dependence of variability level on solar activity; in the years of solar maximum, on the contrary, a slight decrease in the variability is observed. In summer, the level of variability at both middle and high latitudes remains practically unchanged and does not depend on solar activity. The main features in the dynamics of variability are shown to be similar at stations located at other longitudes, except for the East American sector. The result obtained suggests that the short-period TEC variability at high latitudes is primarily related to changes in solar activity, but regular variations in the variability at midlatitudes are probably not associated with heliophysical activity. The observed increase in the level of short-period variability in the winter mid-latitude ionosphere is assumed to be related to an increase in wave activity in the stratosphere.
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5

Ivanov, Aleksey V., and Sergey V. Vasilyev. "Australian Aborigines: geographical variability of craniological features." Вестник антропологии (Herald of Anthropology) 48, no. 4 (December 10, 2019): 243–51. http://dx.doi.org/10.33876/2311-0546/2019-48-4/243-251.

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This work is devoted to the study of craniological traits of Australian aborigines (male and female samples) and their geographical differentiation applying a special program of cranial traits. According to the craniological classification (Pestryakov, Grigorieva, 2004), native population of Australia belongs to the Tropid craniotype, i.e. is characterized by a relatively small size and long, narrow and relatively high form of the skull. The primary settlement of the Australian continent could only origin in the North. There are two contrasting craniotypes in Australia, which probably reflect the two main waves of the aboriginal migration across the continent. The skulls of the first migratory wave were larger and relatively low-vaulted. They are mostly characteristic of the aborigines of South Australia, who later also migrated to the north, to the arid zone of Central Australia. The second major wave is characterized by smaller high-vaulted skulls, which are now characteristic of the population of the north of the continent (Queensland and, especially, the Northern Territory and North-West Australia). The territory of the southeast of Australia (Victoria and New South Wales states) is the most favorable area for human living. The two main migratory waves mixed there, which led to the observed craniological heterosis. The craniological samples of western and northwestern Australia are also of mixed origin, but are more comparable to the Northern Territory groups. The Tasmanians are significantly different from the General Australian population in terms of craniology. This is especially true for the female sample. Perhaps the ancestors of the Tasmanians represented the very first settlement wave of the ancient Sahul continent, before the separation of the island from the mainland.
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Pestriyakov, Aleksandr P., Olga M. Grigorieva, and Yulia V. Pelenitsina. "Australian Aborigines: geographical variability of craniological features." Вестник антропологии (Herald of Anthropology) 48, no. 4 (December 10, 2019): 252–67. http://dx.doi.org/10.33876/2311-0546/2019-48-4/252-267.

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This work is devoted to the study of craniological traits of Australian aborigines (male and female samples) and their geographical differentiation applying a special program of cranial traits. According to the craniological classification (Pestryakov, Grigorieva, 2004), native population of Australia belongs to the Tropid craniotype, i.e. is characterized by a relatively small size and long, narrow and relatively high form of the skull. The primary settlement of the Australian continent could only origin in the North. There are two contrasting craniotypes in Australia, which probably reflect the two main waves of the aboriginal migration across the continent. The skulls of the first migratory wave were larger and relatively low-vaulted. They are mostly characteristic of the aborigines of South Australia, who later also migrated to the north, to the arid zone of Central Australia. The second major wave is characterized by smaller high-vaulted skulls, which are now characteristic of the population of the north of the continent (Queensland and, especially, the Northern Territory and North-West Australia). The territory of the southeast of Australia (Victoria and New South Wales states) is the most favorable area for human living. The two main migratory waves mixed there, which led to the observed craniological heterosis. The craniological samples of western and northwestern Australia are also of mixed origin, but are more comparable to the Northern Territory groups. The Tasmanians are significantly different from the General Australian population in terms of craniology. This is especially true for the female sample. Perhaps the ancestors of the Tasmanians represented the very first settlement wave of the ancient Sahul continent, before the separation of the island from the mainland
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7

Ibraheem, Sumaya, and Said Ghoul. "Software Evolution: A Features Variability Modeling Approach." Journal of Software Engineering 11, no. 1 (December 15, 2016): 12–21. http://dx.doi.org/10.3923/jse.2017.12.21.

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Fu, Zuntao, Liu Shi, Fenghua Xie, and Lin Piao. "Nonlinear features of Northern Annular Mode variability." Physica A: Statistical Mechanics and its Applications 449 (May 2016): 390–94. http://dx.doi.org/10.1016/j.physa.2016.01.014.

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Cunha, Â., R. Ferro, S. Guerra, M. Conceição, J. Correia, C. António, R. Nunes, and A. Simões Torres. "PULMONARY ALVEOLAR PROTEINOSIS: VARIABILITY IN CLINICAL FEATURES." Chest 157, no. 6 (June 2020): A158. http://dx.doi.org/10.1016/j.chest.2020.05.179.

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10

Sahidullah, Md, and Tomi Kinnunen. "Local spectral variability features for speaker verification." Digital Signal Processing 50 (March 2016): 1–11. http://dx.doi.org/10.1016/j.dsp.2015.10.011.

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Dissertations / Theses on the topic "Features variability"

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Crossen, Samantha Lokelani. "Investigation of Variability in Cognitive State Assessment based on Electroencephalogram-derived Features." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1316025164.

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Vasapollo, Claudio. "spatio-temporal Variability of Plant features and Motile Invertebrates in Posidonia oceanica Seagrass Meadows." Thesis, Open University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525851.

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Baker, Brendan J. "Speaker verification incorporating high-level linguistic features." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/17665/1/Brendan_Baker_Thesis.pdf.

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Speaker verification is the process of verifying or disputing the claimed identity of a speaker based on a recorded sample of their speech. Automatic speaker verification technology can be applied to a variety of person authentication and identification applications including forensics, surveillance, national security measures for combating terrorism, credit card and transaction verification, automation and indexing of speakers in audio data, voice based signatures, and over-the-phone security access. The ubiquitous nature of modern telephony systems allows for the easy acquisition and delivery of speech signals for processing by an automated speaker recognition system. Traditionally, approaches to automatic speaker verification have involved holistic modelling of low-level acoustic-based features in order to characterise physiological aspects of a speaker such as the length and shape of the vocal tract. Although the use of these low-level features has proved highly successful, there are numerous other sources of speaker specific information in the speech signal that have largely been ignored. In spontaneous and conversational speech, perceptually higher levels of in- formation such as the linguistic content, pronunciation idiosyncrasies, idiolectal word usage, speaking rates and prosody, can also provide useful cues as to identify of a speaker. The main aim of this work is to explore the incorporation of higher levels of information into the verification process. Specifically, linguistic constructs such as words, syllables and phones are examined for their usefulness as features for text-independent speaker verification. Two main approaches to incorporating these linguistic features are explored. Firstly, the direct modelling of linguistic feature sequences is examined. Stochastic language models are used to model word and phonetic sequences obtained from automatically obtained transcripts. Experimentation indicates that significant speaker characterising information is indeed contained in both word and phone-level transcripts. It is shown, however, that model estimation issues arise when limited speech is available for training. This speaker model estimation problem is addressed by employing an adaptive model training strategy that significantly improves the performance and extended the usefulness of both lexical and phonetic techniques to short training length situations. An alternate approach to incorporating linguistic information is also examined. Rather than modelling the high-level features independently of acoustic information, linguistic information is instead used to constrain and aid acoustic- based speaker verification techniques. It is hypothesised that a ext-constrained" approach provides direct benefits by facilitating more detailed modelling, as well as providing useful insight into which articulatory events provide the most useful speaker-characterising information. A novel framework for text-constrained speaker verification is developed. This technique is presented as a generalised framework capable of using di®erent feature sets and modelling paradigms, and is based upon the use of a newly defined pseudo-syllabic segmentation unit. A detailed exploration of the speaker characterising power of both broad phonetic and syllabic events is performed and used to optimise the system configuration. An evaluation of the proposed text- constrained framework using cepstral features demonstrates the benefits of such an approach over holistic approaches, particularly in extended training length scenarios. Finally, a complete evaluation of the developed techniques on the NIST2005 speaker recognition evaluation database is presented. The benefit of including high-level linguistic information is demonstrated when a fusion of both high- and low-level techniques is performed.
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4

Baker, Brendan J. "Speaker verification incorporating high-level linguistic features." Queensland University of Technology, 2008. http://eprints.qut.edu.au/17665/.

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Speaker verification is the process of verifying or disputing the claimed identity of a speaker based on a recorded sample of their speech. Automatic speaker verification technology can be applied to a variety of person authentication and identification applications including forensics, surveillance, national security measures for combating terrorism, credit card and transaction verification, automation and indexing of speakers in audio data, voice based signatures, and over-the-phone security access. The ubiquitous nature of modern telephony systems allows for the easy acquisition and delivery of speech signals for processing by an automated speaker recognition system. Traditionally, approaches to automatic speaker verification have involved holistic modelling of low-level acoustic-based features in order to characterise physiological aspects of a speaker such as the length and shape of the vocal tract. Although the use of these low-level features has proved highly successful, there are numerous other sources of speaker specific information in the speech signal that have largely been ignored. In spontaneous and conversational speech, perceptually higher levels of in- formation such as the linguistic content, pronunciation idiosyncrasies, idiolectal word usage, speaking rates and prosody, can also provide useful cues as to identify of a speaker. The main aim of this work is to explore the incorporation of higher levels of information into the verification process. Specifically, linguistic constructs such as words, syllables and phones are examined for their usefulness as features for text-independent speaker verification. Two main approaches to incorporating these linguistic features are explored. Firstly, the direct modelling of linguistic feature sequences is examined. Stochastic language models are used to model word and phonetic sequences obtained from automatically obtained transcripts. Experimentation indicates that significant speaker characterising information is indeed contained in both word and phone-level transcripts. It is shown, however, that model estimation issues arise when limited speech is available for training. This speaker model estimation problem is addressed by employing an adaptive model training strategy that significantly improves the performance and extended the usefulness of both lexical and phonetic techniques to short training length situations. An alternate approach to incorporating linguistic information is also examined. Rather than modelling the high-level features independently of acoustic information, linguistic information is instead used to constrain and aid acoustic- based speaker verification techniques. It is hypothesised that a ext-constrained" approach provides direct benefits by facilitating more detailed modelling, as well as providing useful insight into which articulatory events provide the most useful speaker-characterising information. A novel framework for text-constrained speaker verification is developed. This technique is presented as a generalised framework capable of using di®erent feature sets and modelling paradigms, and is based upon the use of a newly defined pseudo-syllabic segmentation unit. A detailed exploration of the speaker characterising power of both broad phonetic and syllabic events is performed and used to optimise the system configuration. An evaluation of the proposed text- constrained framework using cepstral features demonstrates the benefits of such an approach over holistic approaches, particularly in extended training length scenarios. Finally, a complete evaluation of the developed techniques on the NIST2005 speaker recognition evaluation database is presented. The benefit of including high-level linguistic information is demonstrated when a fusion of both high- and low-level techniques is performed.
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5

Hardman-Mountford, Nicholas John. "Environmental variability in the Gulf of Guinea large marine ecosystem : physical features, forcing and fisheries." Thesis, University of Warwick, 2000. http://wrap.warwick.ac.uk/1125/.

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This thesis examines the forcing and behaviour of oceanographic physical features, relevant to recruitment in fish populations, in the Gulf of Guinea Large Marine Ecosystem, on seasonal and interannual time scales. Remotely sensed sea-surface temperature (SST) data covering the period 1981–1991 was used to identify and describe a number of oceanographic features, including the Senegalese Upwelling influence, the Ghana and Côte d’Ivoire coastal upwelling, river run-off, fronts and the previously unrecorded observation of shelf-break cooling along the coast of Liberia and Sierra Leone during the boreal winter. Interannual variability in SST was observed on an approximate three year scale and an extended warm phase was noted between 1987 and 1991. Principal components analysis (PCA) was used to further investigate the variance structure of these SST data and this technique was shown to be able to accurately define boundaries of the Gulf of Guinea system and its constituent subsystems. River discharge data from throughout the Gulf of Guinea was also investigated using PCA, confirming the hydroclimatic regions identified by Mahé and Olivry (1999). The boundaries between these regions correspond closely to those identified between subsystems in the SST data, suggesting a degree of coupling between oceanographic and meteorological variability in the Gulf of Guinea. To further investigate this coupling, local climate data and global/basin scale indices were compared qualitatively and statistically with remotely sensed and in situ SST data and indices of interannual variability in oceanographic features. A new basin scale index was proposed as a measure of zonal atmospheric variability in the subtropical North Atlantic (SNAZI) and this was shown to be the dominant mode of climate variability forcing SST in the Gulf of Guinea. The implications of these results for fisheries recruitment dynamics are discussed.
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Püschel, Georg, Christoph Seidl, Mathias Neufert, André Gorzel, and Uwe Aßmann. "Test Modeling of Dynamic Variable Systems using Feature Petri Nets." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-126018.

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In order to generate substantial market impact, mobile applications must be able to run on multiple platforms. Hence, software engineers face a multitude of technologies and system versions resulting in static variability. Furthermore, due to the dependence on sensors and connectivity, mobile software has to adapt its behavior accordingly at runtime resulting in dynamic variability. However, software engineers need to assure quality of a mobile application even with this large amount of variability—in our approach by the use of model-based testing (i.e., the generation of test cases from models). Recent concepts of test metamodels cannot efficiently handle dynamic variability. To overcome this problem, we propose a process for creating black-box test models based on dynamic feature Petri nets, which allow the description of configuration-dependent behavior and reconfiguration. We use feature models to define variability in the system under test. Furthermore, we illustrate our approach by introducing an example translator application.
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Alfayez, Hanan Mohammed. "A study of variability predictors and clinical features of treated incidence of schizophrenia in Riyadh, Saudi Arabia." Thesis, King's College London (University of London), 2015. http://kclpure.kcl.ac.uk/portal/en/theses/a-study-of-variability-predictors-and-clinical-features-of-treated-incidence-of-schizophrenia-in-riyadh-saudi-arabia(96b62291-569b-48cf-9868-a1d3fc2c5e34).html.

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This Ph.D. thesis is presented as three separate papers, and the overall aim of this research is to describe and achieve a broader and clearer understanding of the epidemiology, aetiology and symptomatology of schizophrenia in Saudi Arabia. The first study provides knowledge about the epidemiology of schizophrenia by investigating the incidence in Riyadh, Saudi Arabia and using the incidence data to describe heterogeneity across districts in Riyadh. In addition, the study tests whether variation in incidence occurs according to nationality, sex, age, marital status, employment status, and income. The second study evaluates the five-factor model in Saudi schizophrenia patients by factor analysis of OPCRIT items as rated from the health records. It also tested whether there was any association between the five factors and demographic data included in OPCRIT. The third study describes the duration of untreated psychosis in Riyadh to identify any association between both patient demographic factors and their first pathway to care with their duration pf untreated psychosis (DUP). The chosen study design for the whole research was a retrospective case note study of all incident cases of schizophrenia over a 2 years period presenting in the capital city of Saudi Arabia. The first study is an epidemiological study with an ecological design, which determines the incidence of schizophrenia amongst the population in Riyadh and to identify associations between incidence of schizophrenia and demographic and socio-environmental characteristics. The second study is a Factor analysis of OPCCI items from a total of 421 schizophrenia patients in Riyadh who presented between 2009 and 2011, while the third study a descriptive DUP (duration of untreated psychosis) study which focused on describing the duration of untreated psychosis in and to identify any association between the DUP and both patients demographic factors and their first pathway to care. The results showed that the incidence rate of schizophrenia in Saudi Arabia is similar to those recorded in Western countries with an associations between schizophrenia incidence and younger age, male gender, single status and unemployment. Lack of association between population density and area level income with schizophrenia incidence was also confirmed. The second study produced five-symptom dimensions, mania, depressions, reality distortion, disorganisation, and manic/bizzare delusions explaining 33% of the total variance. Different dimensions were differently associated with the demographic/premorbid risk factors. Results of the third study showed that the median DUP was 1.41 years. Older age at onset, single mariatl status and higher educational were associated with shorter DUP. Long DUP was associated with help seeking from traditional healers. This thesis has presented a comprehensive picture of the epidemiology of schizophrenia in the capital city of Saudi Arabia, duration of untreated psychosis and a factor analysis of symptoms of schizophrenia.
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Eriksson, Magnus. "Engineering Families of Software-Intensive Systems using Features, Goals and Scenarios." Doctoral thesis, Umeå : Department of Computing Science, Umeå Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1447.

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Di, Fusco Greta. "A Reliable Downscaling of ECG Signals for the Detection of T wave Heterogeneity Features." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016.

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In cardiovascular disease the definition and the detection of the ECG parameters related to repolarization dynamics in post MI patients is still a crucial unmet need. In addition, the use of a 3D sensor in the implantable medical devices would be a crucial mean in the assessment or prediction of Heart Failure status, but the inclusion of such feature is limited by hardware and firmware constraints. The aim of this thesis is the definition of a reliable surrogate of the 500 Hz ECG signal to reach the aforementioned objective. To evaluate the worsening of reliability due to sampling frequency reduction on delineation performance, the signals have been consecutively down sampled by a factor 2, 4, 8 thus obtaining the ECG signals sampled at 250, 125 and 62.5 Hz, respectively. The final goal is the feasibility assessment of the detection of the fiducial points in order to translate those parameters into meaningful clinical parameter for Heart Failure prediction, such as T waves intervals heterogeneity and variability of areas under T waves. An experimental setting for data collection on healthy volunteers has been set up at the Bakken Research Center in Maastricht. A 16 – channel ambulatory system, provided by TMSI, has recorded the standard 12 – Leads ECG, two 3D accelerometers and a respiration sensor. The collection platform has been set up by the TMSI property software Polybench, the data analysis of such signals has been performed with Matlab. The main results of this study show that the 125 Hz sampling rate has demonstrated to be a good candidate for a reliable detection of fiducial points. T wave intervals proved to be consistently stable, even at 62.5 Hz. Further studies would be needed to provide a better comparison between sampling at 250 Hz and 125 Hz for areas under the T waves.
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Swinney, Tyler C. "Sources of Variability in Ceramic Artifacts Recovered from Refuse-Filled Pit Features at the Hahn’s Field Site, Hamilton County, Ohio." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1427983448.

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Books on the topic "Features variability"

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Singh, Nityanand. Climatic and hydroclimatic features of wet and dry spells and their extremes across India. Pune: Indian Institute of Tropical Meteorology, 2009.

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Fuentes, H. R. Effects from influent boundary conditions on tracer migration and spatial variability features in intermediate-scale experiments. Washington, DC: Division of Waste Management, Office of Nuclear Material Safety and Safeguards, U.S. Nuclear Regulatory Commission, 1987.

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Borg, Erik. Noise-induced hearing loss: Literature review and experiments in rabbits : morphological and electrophysiological features, exposure parameters and temporal factors, variability and interactions. Oslo: Scandinavian University Press, 1995.

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Bagdasaryan, Vardan. Leadership. ru: INFRA-M Academic Publishing LLC., 2021. http://dx.doi.org/10.12737/1086964.

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The study of the course "Leadership" is associated with an increasing demand for the formation and disclosure of human leadership potentials. The presented textbook allows you to carry out this work in a targeted way. It summarizes and systematizes the world experience in the development of the theory and practice of leadership, discusses the classification of types of leaders, issues of practical use in leadership scenarios of personal qualities of a person, and offers a methodology for developing team strategies and team building. The distinctive features of the proposed program are its adaptability to the socio-cultural context of Russian society and its strong connection with the task of training the future generation of leaders in the interests of the Russian state. Each of the sections of the textbook is accompanied by practical tasks, the solution of which develops the skills of self-knowledge of a person in the perspective of developing leadership potentials and understanding the variability of leadership strategies. It is focused primarily on the preparation of bachelors studying in pedagogical areas of training, but it can also serve as a basic source for training in the course "Leadership" within the framework of a bachelor's degree in the humanities and the direction of social sciences.
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Newbold, David, and Peter Paschke. Accents and Pronunciation Attitudes of Italian University Students of Languages. Venice: Fondazione Università Ca’ Foscari, 2022. http://dx.doi.org/10.30687/978-88-6969-628-2.

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In recent years, endorsed by the updated (2018) version of the Common European Framework, intelligibility has replaced native-like pronunciation as a primary objective in foreign language teaching. But accent and pronunciation continue to be central issues for university students of languages. This volume presents the results of an investigation into the attitudes of some 370 first-year students at Ca’ Foscari University of Venice, the first such study in Italy, involving students of 13 languages, the principal ones being English, Spanish, French, German and Russian. The survey investigated the importance given to pronunciation in the foreign language, the motivation students have to improve it, and the possible conflict of identity which the acquisition of a ‘foreign’ pronunciation might incur. Students were invited to reflect on the quality and variability of their pronunciation in the two foreign languages they were studying, on their ability to assess it, on affective aspects linked to pronunciation, and on their awareness of phonetic features. They were also asked for their opinions about the pronunciation of English as a Lingua Franca (ELF) and about Italian when spoken with a foreign accent. The contributions in this volume describe the linguistic background of respondents, present and analyse the attitudes which emerge, verify the role of some independent variables (gender, plurilingualism, motivation for enrolment, languages studied, level of proficiency), and (in the case of ELF) report the findings of a follow-up study of master’s level students. The result is an overall picture likely to be of interest to anyone working in the field of university language teaching and who wishes to have a better idea of what students think about foreign language pronunciation.
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Alichi, Ali, Marshall Mills, Douglas Laxton, and Hans Weisfeld. Inflation Forecast Targeting in a Low-Income Country. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198785811.003.0019.

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A model in which monetary policy pursues fully fledged inflation targeting is adapted to Ghana. Model features include: endogenous policy credibility; non-linearities in the inflation process; and a policy loss function that aims to minimize the variability of output and the interest rate, as well as deviations of inflation from the long-term low-inflation target. The optimal approach from initial high inflation to the ultimate target is gradual; and transitional inflation-reduction objectives are flexible. Over time, as policy earns credibility, expectations of inflation converge towards the long-run target, the output-inflation variability trade-off improves, and optimal policy responses to shocks moderate.
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Holliday, N. Penny, and Stephanie Henson. The Marine Environment. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199233267.003.0001.

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The growth, distribution, and variability of phytoplankton populations in the North Atlantic are primarily controlled by the physical environment. This chapter provides an overview of the regional circulation of the North Atlantic, and an introduction to the key physical features and processes that affect ecosystems, and especially plankton, via the availability of light and nutrients. There is a natural seasonal cycle in primary production driven by physical processes that determine the light and nutrient levels, but the pattern has strong regional variations. The variations are determined by persistent features on the basin scale (e.g. the main currents and mixed layer regimes of the subtropical and subpolar gyres), as well as transient mesoscale features such as eddies and meanders of fronts.
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Pineda, Jesús, and Nathalie Reyns, eds. Larval Transport in the Coastal Zone: Biological and Physical Processes. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198786962.003.0011.

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Larval transport is fundamental to several ecological processes, yet it remains unresolved for the majority of systems. We define larval transport, and describe its components, namely, larval behavior and the physical transport mechanisms accounting for advection, diffusion, and their variability. We then discuss other relevant processes in larval transport, including swimming proficiency, larval duration, accumulation in propagating features, episodic larval transport, and patchiness and spatial variability in larval abundance. We address challenges and recent approaches associated with understanding larval transport, including autonomous sampling, imaging, -omics, and the exponential growth in the use of poorly tested numerical simulation models to examine larval transport and population connectivity. Thus, we discuss the promises and pitfalls of numerical modeling, concluding with recommendations on moving forward, including a need for more process-oriented understanding of the mechanisms of larval transport and the use of emergent technologies.
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Finkelstein, Sarah. Reconstructing Middle and Late Holocene Paleoclimates of the Eastern Arctic and Greenland. Edited by Max Friesen and Owen Mason. Oxford University Press, 2016. http://dx.doi.org/10.1093/oxfordhb/9780199766956.013.6.

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The eastern Arctic and Greenland are characterized by diverse paleoclimatic histories. A range of biological, geochemical, and geophysical indicators preserved in ice cores, lake, and ocean sediments, landscape features, or boreholes can be applied to reconstructing Holocene climates over the period of human occupation. Soon after humans arrived in the eastern Arctic around 4800 cal B.P., regional temperatures began to decline. While the proxy records show a strong regional signal, this period of Neoglacial cooling has considerable local variability related to degree of continentality, sea ice conditions and elevation. Much later, the effect of the Medieval Warm Period (AD 850-1360) on the Thule migration appears to have been overstated. Because of the considerable spatiotemporal variability in available paleoclimate reconstructions from the eastern Arctic, data from multiple sites must be integrated, and for archaeological applications, regional syntheses need to be considered alongside highly local reconstructions.
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Vogt, Katja Maria. The Metaphysics of the Sphere of Action. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190692476.003.0007.

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Chapter 7 examines a principle Aristotle formulates in Nicomachean Ethics I.3: ethics must be adequate for its domain. The ethicist must ask herself what her inquiry is about, study the nature of her theory’s subject matter, and observe norms of theorizing that are adequate for it. The subject matter of ethics is value as it figures in human life. Aristotle ascribes two features to this value: difference and variability. Other theorists, he notes, are misled by difference and variability and become relativists. They observe a lack of strict regularity and falsely conclude that the domain of value is messy, unsuitable for any general insights. In Aristotle’s view, the sphere of agency displays for the most part regularities. The chapter defends this proposal as an important metaphysical insight and discusses how it adds to the much-debated claim that situations in which agents act are particulars.
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Book chapters on the topic "Features variability"

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Krüger, Jacob, Thorsten Berger, and Thomas Leich. "Features and How to Find Them." In Software Engineering for Variability Intensive Systems, 153–72. Boca Raton : Taylor & Francis, a CRC title, part of the Taylor & Francis imprint, a member of the Taylor & Francis Group, the academic division of T&F Informa, plc, 2019.: Auerbach Publications, 2019. http://dx.doi.org/10.1201/9780429022067-9.

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Capilla, Rafael, and Juan C. Dueñas. "Modelling Variability with Features in Distributed Architectures." In Software Product-Family Engineering, 319–29. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/3-540-47833-7_28.

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Rajalingham, Rishi, Matthew Toews, D. Louis Collins, and Tal Arbel. "Exploring Cortical Folding Pattern Variability Using Local Image Features." In Medical Computer Vision. Recognition Techniques and Applications in Medical Imaging, 43–53. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-18421-5_5.

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Bogdanova-Beglarian, Natalia, Tatiana Sherstinova, Olga Blinova, and Gregory Martynenko. "Linguistic Features and Sociolinguistic Variability in Everyday Spoken Russian." In Speech and Computer, 503–11. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-66429-3_50.

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Majda, Andrew J., Samuel N. Stechmann, Shengqian Chen, H. Reed Ogrosky, and Sulian Thual. "The Deterministic Skeleton Model and Observed Features of the MJO." In Tropical Intraseasonal Variability and the Stochastic Skeleton Method, 5–27. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-22247-5_2.

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Akhter, Nazneen, Hanumant Gite, Gulam Rabbani, and Karbhari Kale. "Heart Rate Variability for Biometric Authentication Using Time-Domain Features." In Communications in Computer and Information Science, 168–75. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-22915-7_16.

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Gómez-Torres, Estevan, Cecilia Challiol, and Silvia E. Gordillo. "Variability Features in Building Approaches for Context-Aware Mobile Applications." In Advances in Intelligent Systems and Computing, 109–23. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-35740-5_8.

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Bailer-Jones, C. A. L. "Surface Features, Rotation and Atmospheric Variability of Ultra Cool Dwarfs." In Ultracool Dwarfs, 92–110. Berlin, Heidelberg: Springer Berlin Heidelberg, 2001. http://dx.doi.org/10.1007/978-3-642-56672-1_9.

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Shannon, L. V., and G. Nelson. "The Benguela: Large Scale Features and Processes and System Variability." In The South Atlantic, 163–210. Berlin, Heidelberg: Springer Berlin Heidelberg, 1996. http://dx.doi.org/10.1007/978-3-642-80353-6_9.

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Corral, Álvaro, and Antonio Turiel. "Variability of North Atlantic Hurricanes: Seasonal Versus Individual-Event Features." In Extreme Events and Natural Hazards: The Complexity Perspective, 111–25. Washington, D. C.: American Geophysical Union, 2012. http://dx.doi.org/10.1029/2011gm001069.

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Conference papers on the topic "Features variability"

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Rohila, Ashish, and Ambalika Sharma. "Correlation Between Heart Rate Variability Features." In 2020 7th International Conference on Signal Processing and Integrated Networks (SPIN). IEEE, 2020. http://dx.doi.org/10.1109/spin48934.2020.9071381.

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Mortara, Johann, Xhevahire Tërnava, and Philippe Collet. "Mapping features to automatically identified object-oriented variability implementations." In VaMoS '20: 14th International Working Conference on Variability Modelling of Software-Intensive Systems. New York, NY, USA: ACM, 2020. http://dx.doi.org/10.1145/3377024.3377037.

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Foy, Joseph J., Mena Shenouda, Sahar Ramahi, Samuel G. Armato, and Daniel Ginat. "Variability in radiomics features among iDose4 reconstruction levels." In Computer-Aided Diagnosis, edited by Horst K. Hahn and Kensaku Mori. SPIE, 2019. http://dx.doi.org/10.1117/12.2512634.

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Hashimoto, Hirotsugu, Koichi Fujiwara, Yoko Suzuki, Miho Miyajima, Toshitaka Yamakawa, Manabu Kano, Taketoshi Maehara, et al. "Heart rate variability features for epilepsy seizure prediction." In 2013 Asia-Pacific Signal and Information Processing Association Annual Summit and Conference (APSIPA). IEEE, 2013. http://dx.doi.org/10.1109/apsipa.2013.6694240.

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Fantozzi, M. P. Tramonti, F. Artoni, and U. Faraguna. "Heart rate variability at bedtime predicts subsequent sleep features." In 2019 41st Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC). IEEE, 2019. http://dx.doi.org/10.1109/embc.2019.8857844.

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Barrault, Loic, Renato de Mori, Roberto Gemello, Franco Mana, and Driss Matrouf. "Variability of automatic speech recognition systems using different features." In Interspeech 2005. ISCA: ISCA, 2005. http://dx.doi.org/10.21437/interspeech.2005-113.

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Krüger, Jacob, Wanzi Gu, Hui Shen, Mukelabai Mukelabai, Regina Hebig, and Thorsten Berger. "Towards a Better Understanding of Software Features and Their Characteristics." In VAMOS 2018: 12th International Workshop on Variability Modelling of Software-Intensive Systems. New York, NY, USA: ACM, 2018. http://dx.doi.org/10.1145/3168365.3168371.

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Butting, Arvid, Robert Eikermann, Oliver Kautz, Bernhard Rumpe, and Andreas Wortmann. "Controlled and Extensible Variability of Concrete and Abstract Syntax with Independent Language Features." In VAMOS 2018: 12th International Workshop on Variability Modelling of Software-Intensive Systems. New York, NY, USA: ACM, 2018. http://dx.doi.org/10.1145/3168365.3168368.

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Yarmosh, Irina, Veronika Guzeva, Dmitrii Evdokimov, and Svetlana Boldueva. "FEATURES OF HEART RATE VARIABILITY IN PATIENTS WITH VASOSPATIC ANGINA." In XVI International interdisciplinary congress "Neuroscience for Medicine and Psychology". LLC MAKS Press, 2020. http://dx.doi.org/10.29003/m1359.sudak.ns2020-16/546.

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Budak, Erdem Inanc, Faruk Beytar, and Osman Erogul. "Features extraction from respiration rate variability signals for apnea prediction." In 2015 Medical Technologies National Conference (TIPTEKNO). IEEE, 2015. http://dx.doi.org/10.1109/tiptekno.2015.7374613.

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Reports on the topic "Features variability"

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Tare, Medha, and Alison Shell. Designing for Learner Variability: Examining the Impact of Research-based Edtech in the Classroom. Digital Promise, August 2019. http://dx.doi.org/10.51388/20.500.12265/81.

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While research shows that learners differ in many ways, this work must be translated into actionable strategies to benefit students. We describe the results of our partnership with ReadWorks, a widely-used literacy edtech platform, to help them implement research-based pedagogical features that support learners with diverse needs. In a national survey of over 11,000 educators, 89 percent said they were likely to assign more articles on ReadWorks and 82 percent said they were likely to assign higher-level articles as a result of the features available to students. We also examined K-6 students’ (N=1857) use of these optional features when completing digital assignments and found that 92% of students tried at least one new feature and engaged with harder assignments when they used the features than when they did not. Feature use did not differ by student characteristics such as reading proficiency or special education status, suggesting that these features could potentially benefit all students when they need extra support.
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Dunkin, Lauren McNeill. Variability In Long-Wave Runup as a Function of Nearshore Bathymetric Features. Office of Scientific and Technical Information (OSTI), May 2010. http://dx.doi.org/10.2172/1236060.

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Fuentes, H. R., W. L. Polzer, and E. P. Springer. Effects from influent boundary conditions on tracer migration and spatial variability features in intermediate-scale experiments. Office of Scientific and Technical Information (OSTI), April 1987. http://dx.doi.org/10.2172/59985.

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Tare, Medha, Susanne Nobles, and Wendy Xiao. Partnerships that Work: Tapping Research to Address Learner Variability in Young Readers. Digital Promise, March 2018. http://dx.doi.org/10.51388/20.500.12265/67.

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Over the past several decades, the student population in the United States has grown more diverse by factors including race, socioeconomic status, primary language spoken at home, and learning differences. At the same time, learning sciences research has advanced our understanding of learner variability and the importance of grounding educational practice and policy in the individual, rather than the fiction of an average student. To address this gap, LVP distills existing research on cognitive, social and emotional, content area, and background Learner Factors that affect learning in various domains, such as reading and math. In conjunction with the development process, LPS researchers worked with ReadWorks to design studies to assess the impact of the newly implemented features on learner outcomes.
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Brodie, Katherine, Ian Conery, Nicholas Cohn, Nicholas Spore, and Margaret Palmsten. Spatial variability of coastal foredune evolution, part A : timescales of months to years. Engineer Research and Development Center (U.S.), July 2021. http://dx.doi.org/10.21079/11681/41322.

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Coastal foredunes are topographically high features that can reduce vulnerability to storm-related flooding hazards. While the dominant aeolian, hydrodynamic, and ecological processes leading to dune growth and erosion are fairly well-understood, predictive capabilities of spatial variations in dune evolution on management and engineering timescales (days to years) remain relatively poor. In this work, monthly high-resolution terrestrial lidar scans were used to quantify topographic and vegetation changes over a 2.5 year period along a micro-tidal intermediate beach and dune. Three-dimensional topographic changes to the coastal landscape were used to investigate the relative importance of environmental, ecological, and morphological factors in controlling spatial and temporal variability in foredune growth patterns at two 50 m alongshore stretches of coast. Despite being separated by only 700 m in the alongshore, the two sites evolved differently over the study period. The northern dune retreated landward and lost volume, whereas the southern dune prograded and vertically accreted. The largest differences in dune response between the two sections of dunes occurred during the fall storm season, when each of the systems’ geomorphic and ecological properties modulated dune growth patterns. These findings highlight the complex eco-morphodynamic feedback controlling dune dynamics across a range of spatial scales.
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Jury, William A., and David Russo. Characterization of Field-Scale Solute Transport in Spatially Variable Unsaturated Field Soils. United States Department of Agriculture, January 1994. http://dx.doi.org/10.32747/1994.7568772.bard.

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This report describes activity conducted in several lines of research associated with field-scale water and solute processes. A major effort was put forth developing a stochastic continuum analysis for an important class of problems involving flow of reactive and non reactive chemicals under steady unsaturated flow. The field-scale velocity covariance tensor has been derived from local soil properties and their variability, producing a large-scale description of the medium that embodies all of the local variability in a statistical sense. Special cases of anisotropic medium properties not aligned along the flow direction of spatially variable solute sorption were analysed in detail, revealing a dependence of solute spreading on subtle features of the variability of the medium, such as cross-correlations between sorption and conductivity. A novel method was developed and tested for measuring hydraulic conductivity at the scale of observation through the interpretation of a solute transport outflow curve as a stochastic-convective process. This undertaking provided a host of new K(q) relationships for existing solute experiments and also laid the foundation for future work developing a self-consistent description of flow and transport under these conditions. Numerical codes were developed for calculating K(q) functions for a variety of solute pulse outflow shapes, including lognormal, Fickian, Mobile-Immobile water, and bimodal. Testing of this new approach against conventional methodology was mixed, and agreed most closely when the assumptions of the new method were met. We conclude that this procedure offers a valuable alternative to conventional methods of measuring K(q), particularly when the application of the method is at a scale (e.g. and agricultural field) that is large compared to the common scale at which conventional K(q) devices operate. The same problem was approached from a numerical perspective, by studying the feasibility of inverting a solute outflow signal to yield the hydraulic parameters of the medium that housed the experiment. We found that the inverse problem was solvable under certain conditions, depending on the amount of noise in the signal and the degree of heterogeneity in the medium. A realistic three dimensional model of transient water and solute movement in a heterogeneous medium that contains plant roots was developed and tested. The approach taken was to generate a single realization of this complex flow event, and examine the results to see whether features were present that might be overlooked in less sophisticated model efforts. One such feature revealed is transverse dispersion, which is a critically important component in the development of macrodispersion in the longitudinal direction. The lateral mixing that was observed greatly exceeded that predicted from simpler approaches, suggesting that at least part of the important physics of the mixing process is embedded in the complexity of three dimensional flow. Another important finding was the observation that variability can produce a pseudo-kinetic behavior for solute adsorption, even when the local models used are equilibrium.
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Mariano, Arthur J. Inhomogeneous and Nonstationary Feature Analysis: Melding of Oceanic Variability and Structure (INFEAMOVS). Fort Belvoir, VA: Defense Technical Information Center, February 1996. http://dx.doi.org/10.21236/ada306701.

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Mariano, Arthur J., and Toshio M. Chin. Inhomogeneous and Nonstationary Feature Analysis: Melding of Oceanic Variability and Structure (INFAMOVS). Fort Belvoir, VA: Defense Technical Information Center, September 2001. http://dx.doi.org/10.21236/ada628121.

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LaBonte, Don, Etan Pressman, Nurit Firon, and Arthur Villordon. Molecular and Anatomical Characterization of Sweetpotato Storage Root Formation. United States Department of Agriculture, December 2011. http://dx.doi.org/10.32747/2011.7592648.bard.

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Original objectives: Anatomical study of storage root initiation and formation. Induction of storage root formation. Isolation and characterization of genes involved in storage root formation. During the normal course of storage root development. Following stress-induced storage root formation. Background:Sweetpotato is a high value vegetable crop in Israel and the U.S. and acreage is expanding in both countries and the research herein represents an important backstop to improving quality, consistency, and yield. This research has two broad objectives, both relating to sweetpotato storage root formation. The first objective is to understand storage root inductive conditions and describe the anatomical and physiological stages of storage root development. Sweetpotato is propagated through vine cuttings. These vine cuttings form adventitious roots, from pre-formed primordiae, at each node underground and it is these small adventitious roots which serve as initials for storage and fibrous (non-storage) “feeder” roots. What perplexes producers is the tremendous variability in storage roots produced from plant to plant. The marketable root number may vary from none to five per plant. What has intrigued us is the dearth of research on sweetpotato during the early growth period which we hypothesize has a tremendous impact on ultimate consistency and yield. The second objective is to identify genes that change the root physiology towards either a fleshy storage root or a fibrous “feeder” root. Understanding which genes affect the ultimate outcome is central to our research. Major conclusions: For objective one, we have determined that the majority of adventitious roots that are initiated within 5-7 days after transplanting possess the anatomical features associated with storage root initiation and account for 86 % of storage root count at 65 days after transplanting. These data underscore the importance of optimizing the growing environment during the critical storage root initiation period. Water deprivation during this phenological stage led to substantial reduction in storage root number and yield as determined through growth chamber, greenhouse, and field experiments. Morphological characterization of adventitious roots showed adjustments in root system architecture, expressed as lateral root count and density, in response to water deprivation. For objective two, we generated a transcriptome of storage and lignified (non-storage) adventitious roots. This transcriptome database consists of 55,296 contigs and contains data as regards to differential expression between initiating and lignified adventitious roots. The molecular data provide evidence that a key regulatory mechanism in storage root initiation involves the switch between lignin biosynthesis and cell division and starch accumulation. We extended this research to identify genes upregulated in adventitious roots under drought stress. A subset of these genes was expressed in salt stressed plants.
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Russo, David, and William A. Jury. Characterization of Preferential Flow in Spatially Variable Unsaturated Field Soils. United States Department of Agriculture, October 2001. http://dx.doi.org/10.32747/2001.7580681.bard.

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Preferential flow appears to be the rule rather than the exception in field soils and should be considered in the quantitative description of solute transport in the unsaturated zone of heterogeneous formations on the field scale. This study focused on both experimental monitoring and computer simulations to identify important features of preferential flow in the natural environment. The specific objectives of this research were: (1) To conduct dye tracing and multiple tracer experiments on undisturbed field plots to reveal information about the flow velocity, spatial prevalence, and time evolution of a preferential flow event; (2) To conduct numerical experiments to determine (i) whether preferential flow observations are consistent with the Richards flow equation; and (ii) whether volume averaging over a domain experiencing preferential flow is possible; (3) To develop a stochastic or a transfer function model that incorporates preferential flow. Regarding our field work, we succeeded to develop a new method for detecting flow patterns faithfully representing the movement of water flow paths in structured and non-structured soils. The method which is based on application of ammonium carbonate was tested in a laboratory study. Its use to detect preferential flow was also illustrated in a field experiment. It was shown that ammonium carbonate is a more conservative tracer of the water front than the popular Brilliant Blue. In our detailed field experiments we also succeeded to document the occurrence of preferential flow during soil water redistribution following the cessation of precipitation in several structureless field soils. Symptoms of the unstable flow observed included vertical fingers 20 - 60 cm wide, isolated patches, and highly concentrated areas of the tracers in the transmission zone. Soil moisture and tracer measurements revealed that the redistribution flow became fingered following a reversal of matric potential gradient within the wetted area. Regarding our simulation work, we succeeded to develop, implement and test a finite- difference, numerical scheme for solving the equations governing flow and transport in three-dimensional, heterogeneous, bimodal, flow domains with highly contrasting soil materials. Results of our simulations demonstrated that under steady-state flow conditions, the embedded clay lenses (with very low conductivity) in bimodal formations may induce preferential flow, and, consequently, may enhance considerably both the solute spreading and the skewing of the solute breakthrough curves. On the other hand, under transient flow conditions associated with substantial redistribution periods with diminishing water saturation, the effect of the embedded clay lenses on the flow and the transport might diminish substantially. Regarding our stochastic modeling effort, we succeeded to develop a theoretical framework for flow and transport in bimodal, heterogeneous, unsaturated formations, based on a stochastic continuum presentation of the flow and a general Lagrangian description of the transport. Results of our analysis show that, generally, a bimodal distribution of the formation properties, characterized by a relatively complex spatial correlation structure, contributes to the variability in water velocity and, consequently, may considerably enhance solute spreading. This applies especially in formations in which: (i) the correlation length scales and the variances of the soil properties associated with the embedded soil are much larger than those of the background soil; (ii) the contrast between mean properties of the two subdomains is large; (iii) mean water saturation is relatively small; and (iv) the volume fraction of the flow domain occupied by the embedded soil is relatively large.
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