To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Two simulations of turbulent Couette flows were performed at friction Reynolds numbers of 1000 and 2000 in a large box of dimensions $L_x=16{\rm \pi} h$, $L_y=2h$ and $L_z=6{\rm \pi} h$, where h is the semi-height of the channel. The study focuses on the differences in the intensity and scaling of turbulence at these two Reynolds numbers. The 2000 case showed a lack of a clear log layer with a higher value of the Von Kármán constant $\kappa$ than Poiseuille channels. The intensities were well-scaled in the buffer layer and below, with a second maximum of the streamwise intensity at approximately 350 wall units. Contrary to Poiseuille channels, the dissipation scales close to the wall in wall units. This fact can be attributed to the constant value of the derivative of the streamwise intensity in wall units. The intensities of the 2000 case showed remarkable differences compared with those at Reynolds number 1000 at the channel centre, likely due to the organization of large scales of the streamwise fluctuactions, $u$. These large scales were thought to be considered ‘infinite’. However, for the 2000 case, while all the structures have a width of $\ell _z \approx 6/8{\rm \pi} h$, their length varies from $\ell _x \approx 6{\rm \pi} h$ to $\ell _x \approx 16{\rm \pi} h$, which clearly contradicts the trends obtained in the past. This is a new effect that has not been reported for turbulent Couette flow and points to the uncertainty and sensitivity that is observed for certain statistical quantities.
In Mukti Lakhi Mangharam’s book, Freedom Inc.: Gendered Capitalism in New Indian Literature and Culture, she identifies “Freedom Inc.” as a neoliberal celebration of individual empowerment that contrasts with the multiple ways people have imagined freedom in a longer history of Indian literature and philosophy, which are much more open to collective empowerment and political transformation. This critique is certainly valid, but where in it is there the space for “bad” subjects, erotic desires, or for men and women who disobey, who flaunt rules and whose visions of freedom exceed those framed by respectable behavior or collective uplift? This article gives a few examples of what those alternative freedoms would look like, suggesting that in addition to fundamental rights, Indians might need the freedom to be naughty as well.
A scruffy piece of paper covered in notes and dated sketches of snowflake segments has been found caught between the pages of a later book in Whitby Museum’s Scoresby archive. The paper had been cut and folded to secure it round the ship Esk’s logbook. Close examination shows pencil drawing beneath the 22 ink sketches, which can be linked to entries for May 1817 in the logbook and matched to completed snowflakes from William Scoresby Junior’s 1820 book An Account of the Arctic Regions. This is almost certainly the first indication of Scoresby’s process for drawing snowflakes at sea.
The paper also contains jottings on many topics that Scoresby was considering including in his book. Comparing these with the published work, his later fact checking was clearly meticulous.
Propositional temporal logic over the real number time flow is finitely axiomatisable, but its first-order counterpart is not recursively axiomatisable. We study the logic that combines the propositional axiomatisation with the usual axioms for first-order logic with identity, and develop an alternative “admissible” semantics for it, showing that it is strongly complete for admissible models over the reals. By contrast there is no recursive axiomatisation of the first-order temporal logic of admissible models whose time flow is the integers, or any scattered linear ordering.
In the application of rotorcraft atmospheric environment detection, to reflect the distribution of atmospheric pollutants more realistically and completely, the sampling points must be spread throughout the entire three-dimensional space, and the cooperation of multiple unmanned aerial vehicles (multi-UAVs) can ensure real-time performance and increase operational efficiency. In view of the problem of coordinated detection by multi-UAVs, the region division and global coverage path planning of the stereo space to be detected are studied. A whale optimization algorithm based on the simulated annealing-whale optimization algorithm (SA-WOA) is proposed, which introduces adaptive weights with the Levy flight mechanism, improves the metropolis criterion, and introduces an adaptive tempering mechanism in the SA stage. Path smoothing is subsequently performed with the help of nonuniform rational B-spline (NURBS) curves. The comparison of algorithms using the eil76 dataset shows that the path length planned by the SA-WOA algorithm in this paper is 10.15% shorter than that of the WOA algorithm, 13.25% shorter than the SA planning result, and only 0.95% difference from the optimal path length in the dataset. From the perspective of planning time, its speed is similar to WOA, with a relative speed increase of 27.15% compared to SA, proving that the algorithm proposed in this paper has good planning performance. A hardware system platform is designed and built, and environmental gas measurement experiments were conducted. The experimental results indicate that the multi-UAV collaborative environment detection task planning method proposed in this paper has certain practical value in the field of atmospheric environment detection.
Let $\mathcal{V}$ and $\mathcal{U}$ be the point sets of two independent homogeneous Poisson processes on $\mathbb{R}^d$. A graph $\mathcal{G}_\mathcal{V}$ with vertex set $\mathcal{V}$ is constructed by first connecting pairs of points (v, u) with $v\in\mathcal{V}$ and $u\in\mathcal{U}$ independently with probability $g(v-u)$, where g is a non-increasing radial function, and then connecting two points $v_1,v_2\in\mathcal{V}$ if and only if they have a joint neighbor $u\in\mathcal{U}$. This gives rise to a random intersection graph on $\mathbb{R}^d$. Local properties of the graph, including the degree distribution, are investigated and quantified in terms of the intensities of the underlying Poisson processes and the function g. Furthermore, the percolation properties of the graph are characterized and shown to differ depending on whether g has bounded or unbounded support.
The moral self-concept (MSC) describes how children view themselves as moral agents. Research suggests that the MSC may relate to moral behavior, yet little is known about how MSC relates to moral behavior in preschoolers. One hundred six low-income children (Mage = 52.78 months, SD = 6.61 months) and their teachers participated in this study. In the fall, children completed a MSC puppet task measure. In the fall and spring, teachers reported via children’s survey prosocial behavior and aggressive behavior. We used a person-centered approach to identify profiles of MSC, which revealed two profiles of behavior: comforting prosocials and helpful aggressors. Comforting prosocials showed a moderate preference for comforting, a slight preference for helping, and a slight preference for avoiding aggression. Helpful aggressors had a moderate aversion to comforting, a strong preference for helping, and a slight preference for aggressive behavior. Subsequent analysis of covariance analysis revealed that MSC profiles did not differ in concurrent behavior but did differ in behavior 6 months later. The comforting prosocial group participated in more aggression than the helpful aggressors. Additionally, analysis of covariance analysis of change in aggression scores over time showed that comforting prosocials aggression increased, while helpful aggressors aggression decreased. Both groups over time decreased in prosocial behavior, but to different degrees. Overall, findings reveal that the MSC in preschoolers may relate to future not concurrent moral behavior.
Children are no strangers to war and conflict, and for as long as history has been documented, so too has the negative impact of war on children. Attachment theory, which has shone a light upon the ways in which early life experiences can impact individuals across the lifespan, is a helpful lens through which we can view the consequences of war. Similar to the aftermath of war leading to lifelong and transgenerational suffering due to deaths and physical health issues, attachment difficulties created during war further compound long-term damage. Yet, despite our theoretical understanding of the detrimental impact of war on children and on humankind, humanity has failed to find ways to avert, or at least minimise, this unfortunate risk. Instead in this century, we see a growing number of conflicts globally with increasing asylum seekers. In this editorial, we argue that the large-scale disruption to attachment relationships caused by conflict and war is an important consideration for global policy, and that the healthcare community must show leadership in highlighting this serious impact of war.
This essay provides an assessment of the christological analogy for scripture, particularly for its usefulness in aid of a theological ontology of scripture. This analogy implies that scripture has something like ‘two natures’ – human and divine – like Jesus Christ has two natures. I argue that assessment of the analogy has been impaired by a lack of clarity in its application. On the one hand, the ambiguity relates to a tendency to apply the analogy for the (modernist) purposes of securing epistemic authority. On the other hand, I show that there are in fact three distinct forms of the analogy, each implying different things about the ‘twoness’ of scripture as well as its unity. After outlining the three forms of the analogy, I critically assess the unity they ascribe to scripture by means of the analogy.
This article demonstrates the ambivalent sentiments of Koreans toward China as represented by the ideological construction of Hanja (traditional Chinese characters) and Chinese Mandarin embodied in Korean media. Adopting discourse analysis to examine what is described by different language ideologies, this article investigates language discourses concerning Hanja and Mandarin, locating the former mainly within linguistic nationalism and the latter within linguistic instrumentalism. This article puts forth two suggestions. First, investigating linguistic nationalism in relation to the use of Hanja not only displays negative and antagonistic attitudes toward China and the use of Hanja as an embodiment of humiliating historical experiences but also shows ambiguity, fluidity, and vulnerability of Korean national identity. Second, in contrast to Hanja, Koreans' heated enthusiasm to learn Mandarin shows their affection for China as a global market and becomes intertwined with linguistic instrumentalism, embodying an articulation of neoliberalism by reproducing structures of inequality.
Two sets of measurements utilizing hot-wire anemometry and oil-film interferometry for flat-plate turbulent boundary layers, exposed to various controlled adverse and favourable pressure gradients, are used to evaluate history effects of the imposed and varying free-stream gradients. The results are from the NDF wind tunnel at Illinois Tech (IIT) and the MTL wind tunnel at KTH, over the range $800 < Re_\tau < 22\,000$ (where $Re_{\tau }$ is the friction Reynolds number). The streamwise pressure-gradient parameter $\beta \equiv (-\ell /\tau _{w}) \cdot (\partial P_{e}/\partial x)$ varied between $-2 < \beta < 7$, where $\ell$ is an outer length scale for boundary layers equivalent to the half-height of channel flow and the radius of pipe flow, and is estimated for each boundary-layer profile; note that $\tau_w$ is the wall-shear stress and $P_e$ is the free-stream static pressure. Extracting from each profile the three parameters of the overlap region, following the recent work of Monkewitz & Nagib (J. Fluid Mech., vol. 967, 2023, p. A15) that led to an overlap region of combined logarithmic and linear parts, we find minimum history effects in the overlap region. Thus, the overlap region in this range of pressure-gradient boundary layers appears to be in ‘quasiequilibrium’.
We consider a class of nonhomogeneous elliptic equations in the half-space with critical singular boundary potentials and nonlinear fractional derivative terms. The forcing terms are considered on the boundary and can be taken as singular measure. Employing a functional setting and approach based on localization-in-frequency and Littlewood–Paley decomposition, we obtain results on solvability, regularity, and symmetry of solutions.
The Baetican Dressel 20 is probably the most widely diffused amphora of the Roman period, found in large quantities throughout all the Roman and nearby territories. It is the most powerful evidence of the importance of the olive oil trade for Roman society and of olive oil's extraordinary production in the Baetican countryside. This wide diffusion of the amphora and, in some ways, its ubiquity at many archaeological sites, have hindered the study of the early stages of Baetican olive oil production and diffusion. The protagonists were not these spherical containers, commonly stamped up until the late 3rd c. CE, but previous models that evolved rapidly after their origins in Late Republican times. In this paper, we aim to analyze not only the formal characteristics and evolution of these peculiar and still unstandardized containers, but also other aspects linked to their production, as well as the scope of their diffusion.
The present study aims to analyze the existence of different profiles in family caregivers of people with dementia according to psychosocial and resource variables. In addition, it aims to study whether there is a greater representation of each kinship group in each of the profiles and if there are differences in emotional distress among such profiles considering the kinship with the care-recipient. Participants were 288 family dementia caregivers, divided into four kinship groups (wives, husbands, sons and daughters). Psychosocial (familism, dysfunctional thoughts and experiential avoidance), resource (leisure activities and social support) and outcomes (depressive, anxious and guilt symptomatology) variables were collected. A hierarchical cluster analysis using Ward’s method, an exploratory factor analysis of two fixed factors and contingency tables were performed. Five clusters were obtained: Low psychosocial vulnerability-High resources, Low psychosocial vulnerability-Low resources, Mixed, High psychosocial vulnerability-High resources, and High psychosocial vulnerability-Low resources. Results suggested that clusters associated with lower distress were the Low psychosocial vulnerability-High resources and the High psychosocial vulnerability-High resources. Clusters associated with higher distress were the Low psychosocial vulnerability-Low resources and Mixed. High levels of dysfunctional thoughts, familism and experiential avoidance do not always have a maladaptive function. This could depend on sociocultural and resource variables such as the kinship with the caregiver or perceived social support. The identification of profiles of family caregivers potentially needing protection and vulnerable to psychological distress could help to increase the effectiveness of interventions aimed at this population.