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In the second half of the twentieth century, the British printing industry seemed to epitomise the United Kingdom’s status as the sick man of Europe, worn down by changing patterns of consumption, lagging technological modernisation and all-powerful trade unions. Especially the latter were more often than not seen as the problem, not the solution to the industry’s problems. An extravagant set of so-called restrictive practices, critics alleged, was used to hide that print workers were not putting in the work they were paid for while giving them undeserved bonuses that were choking corporate profitability. Print workers and their representatives offered a very different reading, in which the incriminated practices reflected a thoroughly earned privilege to define and distribute waged work. By looking at shop floor practices and conflicts, the article argues that print workers’ defence of non-working intervals articulated a broader vision of their own place in capitalist production.
Given the growing trend of using digital platforms for exporters' internationalization, the management of exporters' online internationalization has become a critical issue. However, academic research in this area remains sparse. Specifically, little is known about when and under what conditions exporters may consider discontinuing the use of a digital platform for exporting, i.e., online de-internationalization. This study develops and tests a theoretical framework for these determinants and the contingencies for exporters' online de-internationalization. Specifically, drawing on the de-internationalization literature, we identify sets of internal and external antecedents of exporters' intention to discontinue the use of digital platforms for exporting. Furthermore, we examine the moderating effect of technological opportunism. Based on a unique sample of Chinese exporters registered on Alibaba.com, the world's largest business-to-business platform, the empirical findings support our proposed determinants of online de-internalization. This article ultimately discusses the theoretical and managerial implications.
Researchers involved in research misconduct proceedings are increasingly threatening or bringing legal defamation claims against the institutions, complainants, and publications involved in the proceedings. Although defamation claims do not often succeed, they can nevertheless be costly and lengthy. This article analyzes certain defamation cases in the research misconduct space and provides advice for institutions and other involved parties seeking to minimize potential defamation liability associated with research misconduct proceedings.
The Codex Angus (Add. MS 40 in the University of Sydney Library's Rare Books and Special Collections) is a Byzantine Gospel lectionary meant for liturgical use. The findings presented here corroborate this catalogue description. There is ample evidence of its heavy use, which indicates a public not a private setting. After a brief description of the manuscript, particularities of its content and appearance are discussed, all of which point to a small rural community, in Northern Greece, as its original owner and user. Together with introducing the codex, this article casts light on the Christian community that might have used it.
State repression of ethno-religious minorities is a widespread practice among dictatorships. Nevertheless, political science literature on the topic presents inconsistent findings regarding the causes and consequences of this phenomenon, largely due to the challenges associated with researching human rights violations in non-democratic regimes. The present systematic literature review covers theme-related articles indexed in the Web of Science database and published in English, Spanish, Japanese, Korean, or Chinese from January 1990 to December 2022 (n=169). By reviewing a wide array of theoretical frameworks, methodologies, and data collection strategies, this article identifies causes, consequences, and endogenous relationships, as well as key gaps in the literature on ethno-religious repression in non-democratic settings, providing a solid starting point for further research.
Childhood obesity is increasing in many countries, including Kuwait. Currently, adiposity is most commonly assessed from simple anthropometric measurements, e.g. height and weight or combined as body mass index (BMI). This is despite these surrogate measurements being poor indices of adiposity. Bioelectrical impedance analysis (BIA) is a popular method for the assessment of body composition providing a measurement of adiposity as absolute fat mass (FM) or FM expressed as a percentage of body weight (%BF). BIA is, however, an indirect predictive method. This study developed a BIA-based prediction equation for body composition assessment in Kuwaiti children and, additionally, a prediction equation for %BF based on sum of skin-fold (SSF) thickness measurements.
Design:
A cross-sectional design was used with primary school recruitment.
Setting:
School population in Kuwait City; in-clinic assessments.
Participants:
158 Kuwaiti children aged 7-9 years. Body composition assessed using bioimpedance spectroscopy and skin-folds with prediction equations generate against deuterium dilution measurement of total body water and fat-free mass (FFM) as reference.
Results:
The newly developed and cross-validated BIA equation predicted FFM with minimal bias (< 1%) and acceptable 2 standard deviation limits of agreement (±1.6 kg equivalent to ±10%) improving on the predictive performance of comparable published equations. Similarly, SSF predicted %BF with small bias (0.2 %BF) but relatively wide limits of agreement (±7 %BF).
Conclusions:
These new equations are suitable for practical use for nutritional assessment in Kuwaiti children, particularly in epidemiological or public health settings although their applicability in other populations requires further research.
In recent years, passive motion paradigms (PMPs), derived from the equilibrium point hypothesis and impedance control, have been utilised as manipulation methods for humanoid robots and robotic manipulators. These paradigms are typically achieved by creating a kinematic chain that enables the manipulator to perform goal-directed actions without explicitly solving the inverse kinematics. This approach leverages a kinematic model constructed through the training of artificial neural networks, aligning well with principles of cybernetics and cognitive computation by enabling adaptive and flexible control. Specifically, these networks model the relationship between joint angles and end-effector positions, facilitating the computation of the Jacobian matrix. Although this method does not require an accurate robot model, traditional neural networks often suffer from drawbacks such as overfitting and inefficient training, which can compromise the accuracy of the final PMP model. In this paper, we implement the method using a deep neural network and investigate the impact of activation functions and network depth on the performance of the kinematic model. Additionally, we propose a transfer learning approach to fine-tune the pre-trained model, enabling it to be transferred to other manipulator arms with different kinematic properties. Finally, we implement and evaluate the deep neural network-based PMP on the Universal Robots, comparing it with traditional kinematic controllers and assessing its physical interaction capabilities and accuracy.
There is a reasonable possibility that the present-day Atlantic Meridional Overturning Circulation is in a bistable regime, hence it is relevant to compute pathways of noise-induced transitions between the stable equilibrium states. Here, the most probable transition pathway of a noise-induced tipping of the northern overturning circulation in a spatially-continuous two-dimensional model with surface temperature and stochastic salinity forcings is computed directly using large deviation theory. This pathway reveals the fluid dynamical mechanisms of such a tipping. Paradoxically it starts off with a strengthening of the northern overturning circulation before a short but strong salinity pulse induces a second overturning cell. The increased atmospheric energy input of this two-cell configuration cannot be mixed away quickly enough, leading to the collapse of the northern overturning cell, and finally resulting in a southern overturning circulation. Additionally, the approach allows us to compare the probability of this transition under different parameters in the deterministic part of the salinity surface forcing, which quantifies the increase in transition probability as the bifurcation point of the system is approached.
The mass balance of lake-terminating glaciers responds to annual atmospheric variations, while calving-induced ice loss at the front is driven by local ice–water interactions. The current glaciological studies underestimate glacier response by neglecting the significant annual ice loss at the terminus through calving processes. This study integrates field measurements with remote sensing data to investigate the glaciological characteristics and proglacial lake evolution of the Gepang Gath glacier in the Chandra basin, Western Himalaya, India. Long-term observations reveal a continuous expansion of the proglacial lake from 0.21 ± 0.06 km2 (1962) to 1.21 ± 0.05 km2 (2023), along with terminus retreat of ∼2.76 km, attributed to calving at the ice–water interface. The glacier’s surface exhibits complex debris cover, with thicknesses up to 35 cm, creating significant spatial variations in surface mass balance. In-situ, glaciological measurements reveal a highly negative glacier-wide mass balance of −0.90 ± 0.30 m w.e. a−1 between the years 2014 and 2023. The geodetic estimates also reveal a negative mass balance of −0.61 ± 0.1 m w.e. a−1 over the past decade (2013–2023). The frontal area change (0.42 km2) and geodetic mass balance show a total volumetric ice loss of −21.77 × 106 m3 w.e. during the same period. Overall, the yearly frontal ice loss exacerbates the mass loss by 17–22%. These findings suggest that the presence of proglacial lakes plays a significant role in intensifying ice mass loss from Himalayan glaciers, strongly regulating their overall evolution.
To sustain its agricultural output, the U.S. relies heavily on imports of potash. Using two different methodologies, this study finds that U.S. import demand falls by approximately four percent in the short run and nine percent in the long run for a 10% rise in the potash import price. Price transmission with leading exporter Canada is imperfect, with U.S. prices rising only 7.7% in the short run when Canadian prices rise by 10%. The findings suggest that policies such as import tariffs would raise costs for U.S. agricultural producers because there are few potash substitutes.
We investigate the statistical properties of kinetic and thermal dissipation rates in two-dimensional/three-dimensional vertical convection of liquid metal ($Pr = 0.032$) within a square cavity. Two situations are specifically discussed: (i) classical vertical convection with no external forces and (ii) vertical magnetoconvection with a horizontal magnetic field. Through an analysis of dissipation fields and a reasonable approximation of buoyancy potential energy sourced from vertical heat flux, the issue of the ‘non-closure of the dissipation balance relation’, which has hindered the application of the GL theory in vertical convection, is partially resolved. The resulting asymptotic power laws are consistent with existing laminar scaling theories and even show certain advantages in validating simulations with large Prandtl number ($Pr$). Additionally, a full-parameter model and prefactors applicable to low-$Pr$ fluids are provided. The extension to magnetoconvection naturally introduces the approximate expression for total buoyancy potential energy and necessitates adjustments to the contributions of kinetic dissipation in both the bulk and boundary layer. The flow dimensionality and boundary layer thickness are key considerations in this analysis. The comprehension of Joule dissipation has been updated: the Lorentz force generates positive dissipation in the bulk by suppressing convection, while in the Hartmann layer, shaping the exponential boundary layer requires the fluid to perform positive work to accelerate, leading to negative dissipation. Finally, the proposed transport equations for magnetoconvection are supported by current direct numerical simulation (DNS) and literature data, and the applicability of the model is discussed.
A topological space has a domain model if it is homeomorphic to the maximal point space $\mbox{Max}(P)$ of a domain $P$. Lawson proved that every Polish space $X$ has an $\omega$-domain model $P$ and for such a model $P$, $\mbox{Max}(P)$ is a $G_{\delta }$-set of the Scott space of $P$. Martin (2003) then asked whether it is true that for every $\omega$-domain $Q$, $\mbox{Max}(Q)$ is $G_{\delta }$-set of the Scott space of $Q$. In this paper, we give a negative answer to Martin’s long-standing open problem by constructing a counterexample. The counterexample here actually shows that the answer is no even for $\omega$-algebraic domains. In addition, we also construct an $\omega$-ideal domain $\widetilde{Q}$ for the constructed $Q$ such that their maximal point spaces are homeomorphic. Therefore, $\textrm{Max}(Q)$ is a $G_\delta$-set of the Scott space of the new model $\widetilde{Q}$ .
Station-keeping control is a critical technology for stratospheric aerostats. For those aerostats that utilise wind field environments to achieve trajectory control, the station-keeping capability of a single aerostat is inherently limited. This limitation can lead to instances of the aerostat flying outside the designated task area, thereby diminishing the effectiveness of station-keeping control. To ensure continuous monitoring of the restricted area for long endurance, dynamic adjustments and cooperative coverage among multiple aerostats are necessary. This paper introduces an optimal coverage algorithm based on Voronoi diagrams and presents a formation control method for stratospheric aerostats that employs the virtual force method and the ${A^{\rm{*}}}$ algorithm, respectively. In a real wind field environment, ten aerostats are deployed to optimally cover the restricted area. Simulation results indicate that the coverage rate of the stratospheric aerostats within the restricted area can exceed 70%, while the network connectivity rate among the aerostats can reach 80% following guidance control during return flights. Furthermore, the stratospheric aerostats that flying out of the restricted area can return through path planning and optimal coverage algorithm, and the networking connectivity rate between aerostats is higher than that using the virtual force method.