On the application of approximation of the central manifold of a stationary point to one critical case

1998 ◽  
Vol 50 (3) ◽  
pp. 489-492
Author(s):  
S. O. Nakonechna
Keyword(s):  
Stationary Point ◽  
Critical Case ◽  
Central Manifold

Qualities of a good essay: an assessment of the writings of Nigerian undergraduates

2020 ◽  
Vol 3 (7) ◽  
pp. 82-88
Author(s):  
Usoro Mark Okono
Keyword(s):  
Critical Case ◽  
State University ◽  
Descriptive Linguistics ◽  
Purposive Sampling ◽  
Writing Test ◽  
Units Of Analysis ◽  
Regular Practice

This research sought to discover the capabilities of Nigerian undergraduates in handling the salient characteristics of essay in English. Such qualities as clarity, economy, simplicity, unity and coherence were the variables in the assessment. The study was conducted within the framework of the theory of descriptive linguistics and its sub-discipline of stylistics. Four topics representing argumentative, descriptive, expository and narrative essays were given to students for each of them to voluntarily choose one and write on in a strictly supervised writing test. All the essays were marked on the above stated variables. Critical case sampling strand of the purposive sampling was used to select four outstanding essays each representing one of the four departments of the Akwa Ibom State University of Nigeria. Paragraph and sentence formed some of the units of analysis. It was found out that the four subjects whose essays were analyzed proved their mettle in producing readable and creative prose in the four genres with some room for improvement. It is suggested that the Use of English programme in Nigerian universities should be extended from one to two years in addition to regular practice in writing by students and feedback from lecturers.

scholarly journals Publications about Women, Science, and Engineering: Use of Sex and Gender in Titles over a Forty-six-year Period

2021 ◽  
pp. 016224392110276
Author(s):  
Mary Frank Fox ◽  
Diana Roldan Rueda ◽  
Gerhard Sonnert ◽  
Amanda Nabors ◽  
Sarah Bartel
Keyword(s):  
Social Stratification ◽  
Critical Case ◽  
Social Inequalities ◽  
Sex And Gender ◽  
Science And Engineering ◽  
Analytical Issue ◽  
Key Features ◽  
And Gender ◽  
Science Policies

This article focuses on key features of the use of sex and gender in titles of articles about women, science, and engineering over an important forty-six-year period (1965–2010). The focus is theoretically and empirically consequential. Theoretically, the paper addresses science as a critical case that connects femininity/masculinity to social stratification; and the use of sex and gender as an enduring, analytical issue that reveals perspectives on hierarchies of femininity/masculinity. Empirically, this article identifies the emergence, development, and stabilization of published articles about women, science, and engineering that use sex and gender in their titles. The distinctive method involves search, retrieval, and review of 23,430 articles, using intercoder reliabilities for inclusion/exclusion. This results in a uniquely specified and comprehensive set of articles on our subject and the identification of titles with sex and gender. Findings point to (1) the growth of gender titles, (2) their increase in every field, (3) differing concentrations of sex and gender titles in journals, (4) a span of telling topic areas, and (5) higher citation rates of gender, compared to sex, titles. Broader implications appear in reasons for the growth of gender titles, meanings of topic areas that occur, insights into social inequalities and science policies, and emerging complexities of nonbinary categories of sex/gender.

scholarly journals Topological Approach to Mathematical Programs with Switching Constraints

2021 ◽  
Author(s):  
Vladimir Shikhman
Keyword(s):  
Stationary Point ◽  
Mountain Pass Theorem ◽  
Strong Stability ◽  
Complete Characterization ◽  
Stationary Points ◽  
Mathematical Programs ◽  
Linear Independence Constraint Qualification ◽  
Point Set ◽  
Stationary Level

AbstractWe study mathematical programs with switching constraints (for short, MPSC) from the topological perspective. Two basic theorems from Morse theory are proved. Outside the W-stationary point set, continuous deformation of lower level sets can be performed. However, when passing a W-stationary level, the topology of the lower level set changes via the attachment of a w-dimensional cell. The dimension w equals the W-index of the nondegenerate W-stationary point. The W-index depends on both the number of negative eigenvalues of the restricted Lagrangian’s Hessian and the number of bi-active switching constraints. As a consequence, we show the mountain pass theorem for MPSC. Additionally, we address the question if the assumption on the nondegeneracy of W-stationary points is too restrictive in the context of MPSC. It turns out that all W-stationary points are generically nondegenerate. Besides, we examine the gap between nondegeneracy and strong stability of W-stationary points. A complete characterization of strong stability for W-stationary points by means of first and second order information of the MPSC defining functions under linear independence constraint qualification is provided. In particular, no bi-active Lagrange multipliers of a strongly stable W-stationary point can vanish.

scholarly journals Sharp thresholds of blow-up and global existence for the Schrödinger equation with combined power-type and Choquard-type nonlinearities

2019 ◽  
Vol 2019 (1) ◽  
Author(s):  
Yongbin Wang ◽  
Binhua Feng
Keyword(s):  
Global Existence ◽  
Finite Time ◽  
Critical Case ◽  
Blow Up ◽  
Critical Mass ◽  
Choquard Equation ◽  
Power Type ◽  
Scale Invariant ◽  
Nonlinear Schrödinger ◽  
Sharp Thresholds

AbstractIn this paper, we consider the sharp thresholds of blow-up and global existence for the nonlinear Schrödinger–Choquard equation $$ i\psi _{t}+\Delta \psi =\lambda _{1} \vert \psi \vert ^{p_{1}}\psi +\lambda _{2}\bigl(I _{\alpha } \ast \vert \psi \vert ^{p_{2}}\bigr) \vert \psi \vert ^{p_{2}-2}\psi . $$iψt+Δψ=λ1|ψ|p1ψ+λ2(Iα∗|ψ|p2)|ψ|p2−2ψ. We derive some finite time blow-up results. Due to the failure of this equation to be scale invariant, we obtain some sharp thresholds of blow-up and global existence by constructing some new estimates. In particular, we prove the global existence for this equation with critical mass in the $L^{2}$L2-critical case. Our obtained results extend and improve some recent results.

scholarly journals EXPRESS: Political parties and organization studies: The party as a critical case of organizing

2021 ◽  
pp. 017084062110109
Author(s):  
Emil Husted ◽  
Mona Moufahim ◽  
Martin Fredriksson
Keyword(s):  
Political Parties ◽  
Institutional Change ◽  
Political System ◽  
Affective Commitment ◽  
Critical Case ◽  
Organizational Dynamics ◽  
Control Mechanisms ◽  
Progressive Change ◽  
Organization Studies ◽  
Organization And Management

Organization scholars have extensively studied both the politics of organization and the organization of politics. Contributing to the latter, we argue for further and deeper consideration of political parties, since: (1) parties illuminate organizational dynamics of in- and exclusion; (2) internal struggles related to the constitution of identities, practices, and procedures are accentuated in parties; (3) the study of parties allow for the isolation of processes of normative and affective commitment; (4) parties prioritize and intensify normative control mechanisms; (5) party organizing currently represents an example of profound institutional change, as new (digital) formations challenge old bureaucratic models. Consequently, we argue that political parties should be seen as ‘critical cases’ of organizing, meaning that otherwise commonplace phenomena are intensified and exposed in parties. This allows researchers to use parties as magnifying glasses for zooming-in on organizational dynamics that may be suppressed or concealed by the seemingly non-political façade of many contemporary organizations. In conclusion, we argue that organization scholars are in a privileged position to investigate how political parties function today and how their democratic potential can be improved in the future. To this end, we call on Organization and Management Studies to engage actively with alternative parties in an attempt to explore and promote progressive change within the formal political system.

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