Stability, vibration and passive damping of partially restrained imperfect columns

A theoretical and experimental study of slender tubular columns for possible use in space structures is conducted in the presence of partial rotational end restraints. Explicit formulas are derived for computing the buckling load and the lowest natural frequency of perfectly straight uniform elastic members with rotational end restraints possessing linear moment-rotation characteristics. An exact solution in the form of a transcendental equation, and a numerical solution using second-order finite-differences are also presented. The presence of an initial imperfection is also incorporated into the numerical procedure. Vibration tests are conducted on an imperfect tubular steel member in the absence of an axial load. A damping concept consisting of a string-mass assembly is explored. Three passive damping configurations involving combinations of three lead shots were investigated. The three lead shot configurations provided considerably greater damping than the single lead shot

Aspects of Political Language and Parallelism

This research is intended to explain the use of parallelism in political speeches. When politicians want to emphasize and reach their aims , they use parallelism . political speeches is pregnant with meaning . Parallelism is a device which expresses several ideas in a series of similar structures . There are different types of parallelism : lexical, syntactic , semantic, synthetic , binary, antithetical . Parallelism works on different levels: 1. Syntactic level in which there are parallel structure of word phrase or sentence , 2. Semantic  level in which there are synonymous and antonymous relations , 3. Phonological level in which we can find alliteration , assonance and rhyme . There are three categories in structural (syntactic) parallelism . First , parallelism at the word level . Secondly, parallelism  at the phrase level , and thirdly parallelism at the clause level. Parallelism is considered as rhetorical and stylistic device . the rhetorical function of parallelism is to strengthen , empower, emphasize, persuade and have a big impact on recipients . The connection between parallelism and political speeches lies in the fact that politicians rely on linguistic repertoire in order to obtain and achieve their objectives and aims , one of these linguistic  configurations is parallelism . a language can be thought of as resource which is drawn upon in order for political goals to be achieved . Parallelism can function as a cohesive device through cohesive repetition since it is considered as a partial repetition . Cohesive repetition is used by politicians to persuade audience and manipulate them for certain aims and issues

A Comparative Predicting Stock Prices using Heston and Geometric Brownian Motion Models

This paper presents a novel approach to predicting stock prices using technical analysis. By utilizing Ito's lemma and Euler-Maruyama methods, the researchers develop Heston and Geometric Brownian Motion models that take into account volatility, interest rate, and historical stock prices to generate predictions. The results of the study demonstrate that these models are effective in accurately predicting stock prices and outperform commonly used statistical indicators. The authors conclude that this technical analysis-based method offers a promising solution for stock market prediction

Investigating the asymmetric linkages between infrastructure development, green innovation, and consumption-based material footprint: Novel empirical estimations from highly resource-consuming economies

The role of a reliable resource consumption measurement is essential for devising a relevant climate policy. The consumption-based material footprint is trade-adjusted domestic resource consumption that presents an accurate picture of the domestic material footprint. Pursuing the same, this study draws asymmetric linkages between infrastructure development, green innovation, and consumption-based material footprint (MF) in the top 11 highly material-consuming countries. Our preliminary findings strictly reject the preposition of data normality and highlight that the observed relationship is quantile-dependent, which may disclose misleading results in previous studies using linear methodologies. In compliance, a novel empirical estimation technique popularized as Method of Moments Quantile Regression is employed that simultaneously deal with non-normality and structural changes in data. The results exhibit that infrastructure development (green innovation) significantly increases (decreases) MF mainly across medium to higher quantiles (medium-higher level of MF). Interestingly, the resource-depleting effect of infrastructure is highest for higher quantiles and lowest for lower quantiles of MF. Economic growth (globalization) increase MF, and their resource-depleting effect is higher (lowest) for lower quantiles and lowest (highest) for higher quantiles. Lastly, population exhibits an inverted-U shape relationship with MF across lower to higher quantiles. These results suggest pertinent policy recommendations

Exposure to NO2 in occupational built environments in urban centre in Lahore

Increased economic growth, urbanisation and substantial rise in automobile vehicles has contributed towards the elevated levels of air pollution in major cities in Pakistan. Aone week study was conducted by using passive samplers to assess NO2 concentration in occupational built environments at two most congested and populated sites of Lahore. Both sites were locatedon the busy roads of Lahore. At Site-I the highest concentration was in outdoors followed by corridor and indoor. While at Site II all the sampling location wereindoors and level were comparable to that of outdoor levelsat Site I. The results suggest the likely contribution of ambient sources in exposure to indoor NO2 in educational and other occupational built environments in urban centres

A comparative assessment of public and private dots laboratories in the Lagos state TB control programme

Background: The purpose of the laboratory services within the framework of the NTP is to provide bacteriologic evidence for the diagnosis, follow-up of TB patients and to document cure at the end of treatment. However to be fully functional, laboratory commodities should be available as needed. This study compared the laboratory hygiene practices and availability of laboratory equipment and other consumables for making diagnosis of TB in public and private DOTS laboratories in Lagos State.Methods: A descriptive comparative cross sectional study comparing availability of commodities in public and private laboratories involved in TB services in Lagos State.Results: Seventeen DOTS laboratories and 34 laboratory scientist/technician were recruited for this study. About three quarter and two thirds of the public and private DOTS laboratories respectively had reagents for smear microscopy. A significantly higher proportion of the public DOTS laboratories had separate area for TB work and separate table for smear preparation (p <0.05). A higher proportion (71.4%) of the laboratory scientist/ technicians at the public compared with 38.5% of those at the private DOTS laboratories had good knowledge of the laboratory diagnosis of TB.Conclusion: Laboratories involved in TB service are not functioning optimally and need to be strengthened.Key Words: Laboratory, DOTS, Consumables, Hygiene.French AbstractContexte : L’objet des services des laboratoires dans le cadre du NTP est de fournir les preuves bactériologiques pour le diagnostic, de suivre les patients tuberculeux et de documenter la guérison a la fin du traitement. Toutefois, pour être pleinement fonctionnel, les produits de laboratoire devraient être disponibles au besoin. Cette recherche comparait les pratiques hygiènes de laboratoire et la disponibilité des équipements de laboratoire et autres consommables pour faire le diagnostic de la tuberculose aux laboratoires de DOTS publics et prives dans l’État de Lagos.Méthodes : Une étude transversale comparative et transversale descriptive comparant la disponibilité des produits aux laboratoires publics et prives  concernes a fournir aux services tuberculeux dans l’état de Lagos.Résultats : Dix – sept laboratoires de DOTS et 34 scientifiques/techniciens ont été recrutés pour cette recherche. Environ trois quarts et deux tiers des laboratoires de DOT publics et prives ont eu réactif respectivement pour la microscopie des frottis. Une proportion significativement plus élevée des laboratoires de DOTS publics a eu un espace séparé pour les travaux de la tuberculose et une table séparée pour la préparation des frottis (p<0,05). Une proportion élevée(71,4%) des scientifiques/techniciens des laboratoires publics comparativement a 38,5% de ceux des laboratoires de DOTS prives avaient une bonne connaissance de diagnostic laboratoire de la tuberculose.Conclusion : Les laboratoires qui ont concerné a fournir les services tuberculeux ne fonctionnent pas de la façon optimale et doivent être renforcés.Mots– clés : Laboratoire, DOTS, consommables, Hygiène

Nonlinear magnetic susceptibility and aging phenomena in reentrant ferromagnet: Cu0.2_{0.2}Co0.8_{0.8}Cl2_{2}-FeCl3_{3} graphite bi-intercalation compound

Linear and nonlinear dynamic properties of a reentrant ferromagnet Cu$_{0.2}$Co$_{0.8}$Cl$_{2}$-FeCl$_{3}$ graphite bi-intercalation compound are studied using AC and DC magnetic susceptibility. This compound undergoes successive phase transitions at the transition temperatures $T_{h}$ (= 16 K), $T_{c}$ (= 9.7 K), and $T_{RSG}$ (= 3.5 K). The static and dynamic behaviors of the reentrant spin glass phase below $T_{RSG}$ are characterized by those of normal spin glass phase with critical exponent $\beta$ = 0.57 $\pm$ 0.10, a dynamic critical exponent $x$ = 8.5 $\pm$ 1.8, and an exponent $p$ (= 1.55 $\pm$ 0.13) for the de Almeida -Thouless line. A prominent nonlinear susceptibility is observed between $T_{RSG}$ and $T_{c}$ and around $T_{h}$, suggesting a chaotic nature of the ferromagnetic phase ($T_{RSG} \leq T \leq T_{c}$) and the helical spin ordered phase ($T_{c} \leq T \leq T_{h}$). The aging phenomena are observed both in the RSG and FM phases, with the same qualitative features as in normal spin glasses. The aging of zero-field cooled magnetization indicates a drastic change of relaxation mechanism below and above $T_{RSG}$. The time dependence of the absorption $\chi^{\prime \prime}$ is described by a power law form ($\approx t^{-b^{\prime \prime}}$) in the ferromagnetic phase, where $b^{\prime \prime} \approx 0.074 \pm 0.016$ at $f$ = 0.05 Hz and $T$ = 7 K. No $\omega t$-scaling law for $\chi^{\prime \prime}$ [$\approx (\omega t)^{-b^{\prime \prime}}$] is observed.Comment: 14 pages, 16 figures, and 2 table

Magnetic relaxation phenomena and cluster glass properties of La{0.7-x}Y{x}Ca{0.3}MnO{3} manganites

The dynamic magnetic properties of the distorted perovskite system La{0.7-x}Y{x}Ca{0.3}MnO{3} (0 <= x <= 0.15) have been investigated by ac-susceptibility and dc magnetization measurements, with emphasis on relaxation and aging studies. They evidence for x >= 0.10 the appearance of a metallic cluster glass phase, that develops just below the ferromagnetic transition temperature. The clusters grow with decreasing temperature down to a temperature T(f0) at which they freeze due to severe intercluster frustration. The formation of these clusters is explained by the presence of yttrium induced local structural distortions that create localized spin disorder in a magnetic lattice where double-exchange ferromagnetism is dominant.Comment: Accepted for publication in Phys. Rev.