scholarly journals Exploiting the Composite Step Strategy to the BiconjugateA-Orthogonal Residual Method for Non-Hermitian Linear Systems

2013 ◽  
Vol 2013 ◽  
pp. 1-16 ◽  
Author(s):  
Yan-Fei Jing ◽  
Ting-Zhu Huang ◽  
Bruno Carpentieri ◽  
Yong Duan
Keyword(s):  
Convergence Rate ◽  
Linear Systems ◽  
Numerical Experiments ◽  
Numerical Instability ◽  
Finite Precision ◽  
Fast Convergence Rate ◽  
History Of ◽  
Finite Precision Arithmetic ◽  
A Minor ◽  
Biconjugate Gradient

The BiconjugateA-Orthogonal Residual (BiCOR) method carried out in finite precision arithmetic by means of the biconjugateA-orthonormalization procedure may possibly tend to suffer from two sources of numerical instability, known as two kinds of breakdowns, similarly to those of the Biconjugate Gradient (BCG) method. This paper naturally exploits the composite step strategy employed in the development of the composite step BCG (CSBCG) method into the BiCOR method to cure one of the breakdowns called as pivot breakdown. Analogously to the CSBCG method, the resulting interesting variant, with only a minor modification to the usual implementation of the BiCOR method, is able to avoid near pivot breakdowns and compute all the well-defined BiCOR iterates stably on the assumption that the underlying biconjugateA-orthonormalization procedure does not break down. Another benefit acquired is that it seems to be a viable algorithm providing some further practically desired smoothing of the convergence history of the norm of the residuals, which is justified by numerical experiments. In addition, the exhibited method inherits the promising advantages of the empirically observed stability and fast convergence rate of the BiCOR method over the BCG method so that it outperforms the CSBCG method to some extent.

scholarly journals An efficient algorithm for estimating the parameters of superimposed exponential signals in multiplicative and additive noise

2013 ◽  
Vol 23 (1) ◽  
pp. 117-129 ◽  
Author(s):  
Jiawen Bian ◽  
Huiming Peng ◽  
Jing Xing ◽  
Zhihui Liu ◽  
Hongwei Li
Keyword(s):  
Parameter Estimation ◽  
Convergence Rate ◽  
Efficient Algorithm ◽  
Numerical Experiments ◽  
Additive Noise ◽  
Mean Squared Errors ◽  
Least Squares Estimators ◽  
The Mean ◽  
Newton Raphson ◽  
Raphson Algorithm

This paper considers parameter estimation of superimposed exponential signals in multiplicative and additive noise which are all independent and identically distributed. A modified Newton-Raphson algorithm is used to estimate the frequencies of the considered model, which is further used to estimate other linear parameters. It is proved that the modified Newton- Raphson algorithm is robust and the corresponding estimators of frequencies attain the same convergence rate with Least Squares Estimators (LSEs) under the same noise conditions, but it outperforms LSEs in terms of the mean squared errors. Finally, the effectiveness of the algorithm is verified by some numerical experiments.

Postactivation Potentiation of Force Is Independent of H-Reflex Excitability

2008 ◽  
Vol 3 (2) ◽  
pp. 219-231 ◽  
Author(s):  
Matthew J. Hodgson ◽  
David Docherty ◽  
E. Paul Zehr
Keyword(s):  
Isometric Force ◽  
Plantar Flexion ◽  
Force Production ◽  
H Reflex ◽  
Postactivation Potentiation ◽  
Neural Excitability ◽  
Reflex Excitability ◽  
Before And After ◽  
History Of ◽  
A Minor

The contractile history of muscle can potentiate electrically evoked force production. A link to voluntary force production, related in part to an increase in reflex excitability, has been suggested.Purpose:Our purpose was to quantify the effect of postactivation potentiation on voluntary force production and spinal H-reflex excitability during explosive plantar fexion actions.Methods:Plantar flexor twitch torque, soleus H-reflex amplitudes, and the rate of force development of explosive plantar fexion were measured before and after 4 separate conditioning trials (3 × 5 s maximal contractions).Results:Twitch torque and rate of force production during voluntary explosive plantar flexion were significantly increased (P < .05) while H-reflex amplitudes remained unchanged. Although twitch torque was significantly higher after conditioning, leading to a small increase in the rate of voluntary force production, this was unrelated to changes in reflex excitability.Conclusion:We conclude that postactivation potentiation may result in a minor increase in the rate of voluntary isometric force production that is unrelated to neural excitability.

A History of Scottish Child Protection Law

2020 ◽  
Author(s):  
Kenneth McK. Norrie
Keyword(s):  
Child Protection ◽  
Juvenile Court ◽  
Institutional Care ◽  
Child Victims ◽  
Contemporary World ◽  
History Of ◽  
A Minor ◽  
Statutory Control ◽  
Radical Shift

This book explores the development of Scottish child protection law from its earliest days in the poor law, tracing the changing assumptions that underlay child protection processes, and the radical shift of emphasis from private (charitable) endeavour to public (local authority) duty. This book looks at the developing legal processes for removing children from abusive or neglectful environments, explores how child offenders and child victims came to be dealt with in the same processes, and examines the reasons why Scots law has managed to continue to cleave its own procedural path in the contemporary world. It explores both processes and outcomes, explaining how the juvenile court evolved into the children’s hearing, and it examines the substantive continuities between the various orders that could be made over children. The regulation of boarding out and fostering of children is compared with the regulation of institutional care, and the evolution of aftercare provisions is explained. The book also offers an analysis of the (dubious) legal basis for the Imperial practice of sending troubled children to the colonies, as part of a deliberate policy of spreading British “stock” across the world. The final chapter traces the origins and statutory control of the practice of adoption of children, from its days as an informal arrangement through its early manifestation as a minor action changing status to its present position as the most radical order that a court of law can make.

Reflections on the Status and Direction of Psychology: An External Historical Perspective

2013 ◽  
Vol 44 (2) ◽  
pp. 244-261 ◽  
Author(s):  
Amedeo Giorgi
Keyword(s):  
Historical Perspective ◽  
Phenomenological Approach ◽  
Natural Sciences ◽  
Gestalt Theory ◽  
The Everyday ◽  
The Status ◽  
History Of ◽  
A Minor ◽  
Aron Gurwitsch

Abstract Whenever one reads internal histories of psychology what is covered is the establishment of a lab by Wundt in 1879 as the initiating act and then the breakaway movements of the 20th Century are discussed: Behaviorism, Gestalt Theory, Psychoanalysis, and most recently the Cognitive revival. However, Aron Gurwitsch described a perspective noted by Cassirer and first developed by Malebranche, which dates the founding of psychology at the same time as that of physics in the 17th Century. This external perspective shows the dependency of psychology upon the concepts, methods and procedures of physics and the natural sciences in general up until the present time. Gurwitsch argues that this approach has blocked the growth of psychology and has assured its status as a minor science. He argued that the everyday Lifeworld achievements of subjectivity are the true subject matter of psychology and that a phenomenological approach to subjectivity could give psychology the authenticity it has been forever seeking but never finding as a naturalistic science. Some clarifying thoughts concerning this phenomenologically grounded psychology are offered, especially the role of desire. The assumption of an external perspective toward the history of psychology fostered the insights about psychology’s scientific role.

Mela's Phoenician Geography

2000 ◽  
Vol 90 ◽  
pp. 70-94 ◽  
Author(s):  
Roger Batty
Keyword(s):  
English Translation ◽  
Technical Writing ◽  
Roman Period ◽  
Poor Reading ◽  
History Of Cartography ◽  
History Of ◽  
The Subject ◽  
Many Sources ◽  
A Minor ◽  
Ancient Geography

The appearance in 1998 of F. E. Romer's English translation of Pomponius Mela's De Chorographia has helped to raise further the profile of this previously rather obscure author. Indeed, since the publication a decade previously of the Budé edition by Alain Silberman, interest in Mela seems to have grown quite steadily. Important contributions in German by Kai Brodersen have widened our appreciation of Mela's place within ancient geography as a whole, and his role within the history of cartography has been the subject of a number of shorter pieces.One element common to all these works, however, is a continuing tendency to disparage both Mela himself and the work he created. This is typified by Romer, for whom Mela was ‘a minor writer, a popularizer, not a first-class geographer’; one ‘shocking reason’ for his choice of genre was simply poor preparation, ‘insufficient for technical writing in geography’. Similar judgements appear in the works of Brodersen and Silberman. Mela's inaccuracies are, for these critics, typical of the wider decline of geography in the Roman period. Perhaps such negative views sprang initially from a sense of frustration: it was counted as one of our author's chief defects that he failed to list many sources for his work. For scholars interested in Quellenforschung it makes poor reading. Yet, quite clearly, the De Chorographia has also been damned by comparison. Mela's work has been held against the best Graeco-Roman learning on geography during antiquity—against Strabo, Ptolemy, or Pliny—and it has usually been found wanting. Set against the achievements of his peers, his work does not stand close scrutiny. Thus, for most scholars, the text has been read as a failed exercise in technical geography, or a markedly inferior document in the wider Graeco-Roman geographical tradition.

scholarly journals Bibliometric Assessment of Research Conference Effectiveness: on the proceedings of Ryazan Pedagogical Readings (2015-2020)

2021 ◽  
pp. 7-16
Author(s):  
Т.В. Еременко
Keyword(s):  
Conference Proceedings ◽  
Citation Index ◽  
Publication Rate ◽  
Minor Effect ◽  
Bibliometric Indicators ◽  
Russian Science ◽  
Russian Science Citation Index ◽  
History Of ◽  
Pedagogical Research ◽  
A Minor

В статье представлены результаты исследования, цель которого заключалась в оценке результативности Рязанских педагогических чтений как формы научной коммуникации с применением метода библиометрического анализа. Основными критериями анализа выступили структура массива публикаций в сборниках трудов конференции и структура массива цитирований трудов конференции. Распределение публикаций и их цитирований проведено с использованием в совокупности шести библиометрических индикаторов. Эмпирическую базу исследования составила подборка из 500 записей, сформированная путем поиска в РИНЦ и включившая статьи сборников конференции за период с 2015 по 2020 год. В результате библиометрического анализа была обнаружена «скачущая динамика» развития Рязанских педагогических чтений, раскрыта география научных связей данного мероприятия c наблюдаемым доминированием авторов-рязанцев, выявлен слабый эффект воздействия продуцируемого на этой конференции научного знания на развитие педагогических исследований и оценен ареал цитирования трудов конференции в научной периодике. The article presents the results of a research whose aim was to assess the effectiveness a scholarly conference Ryazan Pedagogical Readings through bibliometric assessment. The analysis encompasses such parameters as the corpus of articles published in the proceedings of the conference and citation index. The author employs six bibliometric indicators to assess the citation index and the publication rate. The research assesses 500 references cited within the Russian Science Citation Index database (conference proceedings of 2015–2020). Bibliometric analysis shows erratic dynamics in the history of Ryazan Pedagogical Readings, assesses the geography of research connections, reveals the prevalence of Ryazan researchers, detects a minor effect of the conference on the development of pedagogical research, performs citation analysis of journals.

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