State Boundaries Research Articles

Control of the Cauchy System for an Elliptic Operator: The Controllability Method

In this paper, we are dealing with the ill-posed Cauchy problem for an elliptic operator. This is a follow-up to a previous paper on the same subject. Indeed, in an earlier publication, we introduced a regularization method, called the controllability method, which allowed us to propose, on the one hand, a characterization of the existence of a regular solution to the ill-posed Cauchy problem. On the other hand, we have also succeeded in proposing, via a strong singular optimality system, a characterization of the optimal solution to the considered control problem, and this, without resorting to the Slater-type assumption, an assumption to which many analyses had to resort. On occasion, we have dealt with the control problem, with state boundary observation, the problem initially analyzed by J. L. Lions. The proposed point of view, consisting of the interpretation of the Cauchy system as a system of two inverse problems, then called naturally for conjectures in favor of which the present manuscript wants to constitute an argument. Indeed, we conjectured, in view of the first results obtained, that the proposed method could be improved from the point of view of the initial interpretation that we had made of the problem. In this sense, we analyze here two other variants (observation of the flow, then distributed observation) of the problem, the results of which confirm the intuition announced in the previous publication mentioned above. Those results, it seems to us, are of significant relevance in the analysis of the controllability method previously introduced.

Fledgling Farms and Failing Health: How the Polypore State Transforms the Multispecies Relations in Serbia’s Raspberry Fields

Abstract Extending from an ethnographic case study that demonstrates the existential troubles of Serbian farmers to continue raspberry production for the global market, this article anthropologically hones in on the intertwining of human and non-human labour (production) with socio-economic and techno-scientific policies of care (reproduction). Different waves of state transformation—the build-up and decay of formal employment coupled with the emergence, then exhaustion of the welfare state, its socio-liberal transformation in the early 2000s, followed by its polypore repurposing for illiberal ends since 2012, have led to a zombified hope in the state’s will to care for its population. Skilled and unskilled workers have emigrated to Western labour markets, while the climate crisis gained momentum because of the underfunding of critical infrastructures of value. Adopting a Marxist-Eco-Feminist care perspective, the case study thus embeds seemingly disconnected concerns within wider struggles on the boundaries of the (welfare) state, economy and techno-science.

Inpatient surgical treatment in mass casualty situations and disasters-Principles, targets, concepts, preparation

The war in Ukraine and the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pandemic have moved the resilience of the healthcare system in Germany into the focus of a broad discussion. The preparation for such a damage situation is characterized by the relationship between the available treatment capacity and needs which go far beyond the norm. The aim of a resilient healthcare system must be to adequately react to such exceptional situations. Particularly in acute disaster and mass casualty situations, medical standards and an individualized surgical treatment must be maintained for as long as possible. The aim of this article is to elucidate the current terminology on medical treatment of patients in disasters from a surgical perspective, to further develop available concepts and possible concepts of crisis management based on three schematically presented scenarios. Furthermore, the general reaction possibilities for mobilization of treatment capacities are described. In order to uniformly collate the quality of medical treatment in a damage situation, it is meaningful to include the stages of individualized treatment, compensated crisis care and decompensated crisis care. Within the framework of a mass casualty situation or a disaster, traumatological and surgical patients are predominant and the aim must be to maintain or restore the stage of a compensated crisis management. Depending on the extent of the damage situation, this can only be realized in a timely manner independent of state boundaries and by a superordinate central management structure. For a comprehensive provision of surgical treatment capacities, the depiction of a continuous overview of the situation with current resources and structural data of the hospitals in the affected region is necessary. The aim of all efforts and preparations must therefore be to durably strengthen hospitals and to train and develop this with respect to coping with a damage situation in disaster medicine. In this respect it is important to establish a consensus on terminology, the type of treatment and the tactical strategic principles of surgical treatment to cope with a disaster or damage situation.

The magnifying role of the banking sector during depressions

Is there a magnifying role of the banking sector during depressions? How can a financial perturbation, possibly small-sized, create large impacts on output and enduring recessions? What is the role played by the massive stock of due claims brought about by a financial crisis? We address these questions by putting forth a general equilibrium model endowed with a banking system in which due claims – henceforth named due loans – and occasionally binding credit restrictions coexist and their effects reinforce each other. Under “bad” financially-driven perturbations due loans hike and the concomitant opportunity, holding, regulatory, and impairment costs trigger sizable increases in external finance premia and promote credit restrictiveness. Firms’ net worth collapses as they are called in to finance banks’ problems, and their ability to invest and accumulate capital becomes compromised. The amplification effect can be very large: the full-fledged banking model may only require a perturbation of one-tenth the size of a plain vanilla version to deliver the same output drop at the trough. Effects are non-linear, since credit restrictions remain slack on the boundary of the steady state, and asymmetric, since these restrictions play no role whatsoever under “good shocks.”

How Sovereign Boundaries of Regional Alliance Member States Are Determined: The Case of the European Union

This essay explores the complex relationship between the sovereignty of the European Union (EU) and its member states. The concept of sovereignty is the base of political science, and the EUs foundation has created tension among its member states regarding the balance between pooling sovereignty and preserving it. The essay uses the case study of Brexit to examine the extent to which EU member states can achieve sovereignty within the current political climate. Theoretical frameworks such as neo-functionalism and intergovernmentalism are used to analyze the relationship between member states and the supranational EU institutions. The essay aims to provide insight into the complex dynamics of sovereignty in the EU and offers potential solutions for balancing member-state sovereignty with the need for collective decision-making within the EU.

Field-free self-oscillation of magnetization enabled by the fieldlike spin-orbit torque

Fieldlike spin-orbit torque, which behaves like a torque from a magnetic field, but relies on the current together with the damplike one, was recognized to influence magnetization switching. However, its role on magnetic oscillations remains to be explored. By linear stability analysis and energy averaging technique, we obtain analytic formulas for the stable boundaries of various states. Then, a phase diagram is constructed, which is controlled by the current and a tunable ratio β of the fieldlike torque to the dampinglike one. We find that some new stable, bistable and dynamic states come forth. Especially, a bias-field-free self-oscillation emerges for negative β, which enables the average energy balance between the dampinglike torque and the intrinsic damping. There occur two kinds of oscillations, analogous to the usual in-plane and out-of-plane precessions. If increasing the current, the frequency declines for the former, and subsequently rises for the latter. Varying β slightly affects the frequency range, but dramatically alters the adjustable range of current. In addition, the phase diagram indicates that the switching direction reverses with β stepping over −1/α with α being the damping constant, and the switching current decreases with ∣β∣ increasing.

Delineating humanistic underpinnings in the midst of posthuman evolution: A study of Hannu Rajaniemi’s Jean le Flambeur trilogy

This research aims to delve into the intricate and multilayered connection between humans and posthumans, as depicted in Hannu Rajaniemi's Jean le Flambeur trilogy. This Finnish American author's trilogy, consisting of The Quantum Thief (2010), The Fractal Prince (2012), and The Causal Angel (2014), paints an insightful picture of this interaction. The investigation aims to illuminate the emergence of humanity in an extremely posthuman and postsingular landscape, arguing that one must understand humanity as not entirely separate from posthumanism. Instead, humanity should be considered a specific case, or limit case, of the broader posthumanist concept. The form of humanity that arises from the boundaries of an extreme posthuman state of evolution will not mirror the pre-posthuman state; instead, it will transform into a more comprehensive, inclusive entity. The analysis of these three novels will illustrate how Rajaniemi's work does not entirely dismiss human agency. Instead, it recontextualizes and reshapes it within a dramatically different posthuman setting.

Influence of post-expansion residual stress on the fatigue life of the supercharged boiler

The stress distribution on boiler tubesheets becomes very complex due to the combined effects of thermal-mechanical load and residual stress from expansion in numerous expanded joints. This study determined the residual stress distribution generated by the expansion process on the boiler drum, which was used as the initial stress state boundary to simulate continuous steam charging and discharging cycles. Different fatigue assessment methods were employed to evaluate the impact of `residual stress on fatigue life. The results indicated that the residual stress exhibited higher values in the central region and lower values on the sides. When considering the post-expansion residual stress, there was a reduction of 10.4%/20% and 8.9% in the permissible number of cycles based on the maximum shear stress and distortion energy theories, respectively. It is crucial to account for the fatigue weakening caused by the expansion process in the fatigue evaluation of pressure vessels.

Equations of State and Phase Boundaries of SiO2 Polymorphs Under Lower Mantle Conditions

AbstractSiO2 is an important modally abundant component of terrestrial planets, while there are few studies that quantitatively determine the properties of silica under simultaneously high‐temperature and high‐pressure conditions. In this study, thermal properties of stishovite, CaCl2‐type SiO2 and seifertite have been obtained by using extensive first‐principles simulations. The quasi‐harmonic approximation and intrinsic anharmonic effects were considered, and a generalized rescaling method was adopted to eliminate systematic errors in the simulation results. Based on the simulation data, we have established new equations of state for the SiO2 polymorphs and determined their phase boundaries. Anharmonicity has been demonstrated to show noticeable effects on their thermal properties and phase boundaries. With the new results, we found that SiO2 polymorphs show increasing buoyancy in the subducted basaltic slabs at depths greater than ∼800–900 km. In the normal lower mantle, they are readily stable over a broad range of depths approximately from 1,500 km to 2,600 km. This implies that SiO2 polymorphs may contribute to the lateral heterogeneity in the deep lower mantle as observed by small‐scale seismic scatterers.

The Right to Work and American Inequality

Labor historians describe Right to Work (RTW) as among the most consequential pushbacks against the early twentieth-century ascent of labor unions. Yet research on the economic consequences of RTW remains mixed, with nearly all research centered empirically and theoretically on the time surrounding RTW passage. In the current study, I use 41 waves of longitudinal data from the Panel Study of Income Dynamics between 1968 and 2019 to empirically and theoretically extend the mechanisms that link RTW and economic outcomes. First, following the vast majority of research on RTW, I show the demobilizing effects for labor following RTW passage: mean wages decline, wage inequality increases, and the union premium is halved in the middle and lower portion of the wage distribution. Second, I move theoretical focus beyond the time surrounding law enactment, arguing for a second-order effect whereby RTW institutionalizes a logic of polarized economic distributions and low labor power. To test this mechanism, I develop a novel strategy of comparison across respondents who are differentially mobile across state boundaries. I find individuals who cross RTW contexts experience a unique decline in mean wages and increase in wage variance, but this distinct trend can be explained by state-level institutional variation across RTW and non-RTW states. Thus, RTW is not only consequential in the periods around its passage, but also in establishing a long-standing, high-inequality regime. Results reveal multiple mechanisms by which RTW contributes to the long-run processes of union decline and broadly shared inequality growth.

Effect of concurrent thermal grooving and grain growth on morphological and topological evolution of a polycrystalline thin film: Insights from a 3D phase-field study

Experiments and computer simulations of bicrystals have been extensively used to study the role of thermal grooving on grain boundary motion. Although these studies provide a fundamental understanding of the factors that affect boundary motion, they do not capture interactions between the grain boundary network and (solid-vapor) surface on the overall grain growth kinetics. To understand the complex interactions between the thermal groove and the grain boundary, we developed a three-dimensional phase-field model to simulate concurrent capillary-driven grain growth and surface diffusion-controlled thermal grooving. We systematically studied the role of film thickness and surface diffusivity on the interactions between thermal grooving and grain growth in polycrystalline films. To make outcomes statistically significant, we implement an efficient active parameter tracking algorithm that can simulate a large number of grain orientations. Our results show an increase in the degree of stagnation with the reduction in film thickness due to the modification of boundary curvature normal to the surface of the film. Large-scale simulations of polycrystalline films show the development of nonuniform groove surface profiles with varying degrees of asymmetry that correspond to steady state, decelerating, and stationary boundaries. The stagnation of grain boundaries shows dependence on groove depth and topological distribution of grains. The critical grain size for grain boundary stagnation and grain size distribution varies with film thickness. We also demonstrate, using various tailored configurations, how concomitant thermal grooving can lead to the complete arrest of grain growth.

Applying molecular genetic data at different scales to support conservation assessment of European Habitats Directive listed species: A case study of Eurasian otter in Austria.

Evaluating intraspecific genetic structure and diversity is fundamental to assessing a species' conservation status, but direct incorporation of such information into legal frameworks such as the EU's Habitats Directive is surprisingly rare. How genetic structure aligns with EU member state boundaries or biogeographic regions may be very important in designing management plans or achieving legislative goals. The Eurasian fish otter experienced a sharp population decline during the 20th century but is currently re-expanding in several countries. The species is listed under Annex II and IV of the European Habitats Directive, and member states are obliged to assess the species separately across different biogeographic regions. We genotyped 2492 otter spraints across four provinces in Austria, collected between 2017 and 2021. A total of 384 different genotypes were identified, supporting densities along river habitats from 0.1 to 0.47 otters per river km (mean: 0.306), with a resampling-based simulation supporting limited density overestimation at survey lengths of 20 km or more. Three distinct genetic clusters were revealed, two of them presumably reflecting two relict populations whereas the source of the third cluster is unknown. The geographic extent of the three clusters does not coincide with provincial or biogeographic boundaries, both relevant for assessment and management within existing national or European legislative frameworks. We advocate more consideration of genetic structure in the assessment and conservation management planning of species listed in the European Habitats Directive.

On peoples, history, and sovereignty

ABSTRACTThe article opens with materials from the author’s research among east Slavs in Poland: a close-up portrayal of villagers classified as Ukrainians in the Polish People’s Republic, some of whom had no developed national consciousness; and an equally brief account of a postsocialist project in a nearby city, in which the boundaries between rival peoples were clearly drawn. Explanations for inconsistencies between individuals and enduring tensions between groups must be sought in the complicated history of this ethnic borderland. Collective identities and peoplehood are plastic. Outcomes are shaped by many factors: language and religion are fundamental, but account must also be taken of the contingencies of imperial politics, violence, industrialization, and the aspirations of intellectuals. The distinction between historical and non-historical peoples is found to be useful, but neither Ernest Gellner’s theory of nationalism nor conventional accounts of colonialism have much traction in this case. The implicit presentism of those who sacralize state boundaries at one point in time in the name of “sovereignty” has affinities with the functionalist presentism developed by Bronisław Malinowski in very different, non-European contexts. While that paradigm has few adherents nowadays, Malinowski’s posthumous critique of the state and “political sovereignty” is salutary for understanding the ongoing catastrophe in Ukraine.

Particle-scale simulations of the compression and shearing of kaolin clay

This paper presents a new model for particle-scale simulations of clay. Using the discrete-element method, featuring realistically shaped platelets with separate interactions between the various platelet surfaces, simulations of isotropic normal compression and triaxial shearing are performed. A normal compression line is established, and for the first time so is a critical state line, which is parallel to the normal compression line in e–log p space. The critical state line is obtained from conventional, constant mean stress and constant volume tests on normally consolidated and overconsolidated samples. The critical state line appears linear in q–p space and the first insights into a state boundary surface for the clay are established. This new model appears capable of capturing the key features of macroscopic clay behaviour.

Environment and Politics : A Study

In the 21st century, environmental problems have become a common phenomenon across the globe. It has become very difficult to overlook environmental issues. These problems cross boundaries of nation states to include issues like overuse of resources, ozone depletion, climate change, destruction of endangered species and overfishing in global waters. Problems like climate change and ozone layer depletion not only affect the lives and health of people, but touch every nation and community. Environment problem in one area can have impact over other parts of the world too since these problems are highly complex and interconnected, for example – air pollution in one region of Europe can be caused by activities in another area. Due to the heavy destruction inflicted on the environment through the human activities, an urgent need is felt to save and conserve it. This is the reason why environment is no longer viewe d as a minor matter. Until unless effective steps are taken, environmental problems will have long term effects on people and will end up destroying the future of Earth. Global efforts are required to solve various environmental problems.

The spillover effects of labor regulations on the structure of earnings and employment: Evidence from occupational licensing

This paper measures how labor regulations affect the structure of earnings and employment in other occupations in the context of occupational licensing. Using a state boundary discontinuity design, I estimate the market spillovers of licensing on other occupations with similar skills, which I classify using hierarchical clustering techniques on skills data from O*NET. I find evidence of negative earnings and employment spillovers, with the largest earnings effects concentrated among women, black, and foreign-born Hispanic workers. These effects lead to greater earnings inequality. The results are most consistent with licensing changing skill- and industry-specific labor demand and with a monopsony model where licensing increases search costs and reduces workers’ outside options.

Surface Acoustic Wave Interaction with a Mixture of Oxygen and Nitrogen

Parameters of surface acoustic waves (SAW) are very sensible to change of physical conditions of a propagation medium. In the classical theory formulation, the waves are guided along the boundary of semi-infinity solid state and free space. A real situation is more complex and a medium commonly consists of two physical components: a solid substrate and a gaseous or liquid environment. In the case of stress-free substrate, the strongest impact on SAW properties have surface electrical and mechanical conditions determined by solids or liquids adhering to the boundary. This impact is utilised for constructing sensors for different gases and vapours e.g. (Jakubik et al., 2007; Hejczyk et al., 2011; Jasek et al., 2012). The influence of gaseous environment on the SAW properties is usually very weak and ignored. However, in certain condition it can be significant enough to be applied to sensor construction. In general, it concerns Rayleigh wave devices where energy leakage phenomenon is perceptible, especially when the gas being detected considerably changes the density of environment. The paper presents the results of experiments with oxygen-nitrogen mixture. Their primary aim was focused on finding the dependence of resonant frequency and attenuation in SAW resonator on parameters and concentrations of the gas in the environment.

Experimental Investigation on Shear Behavior of Partially Saturated Silty Soil under Constant Water Content and Constant Void Ratio Conditions

Abstract Matric suction is a crucial parameter that affects how unsaturated soils behave in terms of shear strength. Understanding it is essential for solving geotechnical problems like the stability of unsaturated soil slopes, foundations, embankments, and retaining walls. To investigate the shear behavior in unsaturated soil, a double cell triaxial test apparatus is used in the current research to carry out a series of triaxial compression tests under constant water content and constant void ratio conditions. Samples of silty soil, named DL-clay, were prepared with three different degrees of compaction: 80 %, 83 %, and 86 %, and water contents of 20 % (optimum water content) and 25 %. The soil samples were consolidated isotropically under net confining pressures of 300 kPa and 500 kPa before being sheared with constant volume. In another series of tests, water was infiltrated into the sample at 0 kPa deviatoric stress before the start of shearing with constant volume. Some specimens were also sheared with constant confining pressure for comparison purposes. From the test results, it is ascertained that maintaining a constant volume, i.e., constant void ratio during shearing, gives contour-like trajectories that can aid in defining the state boundary surface of unsaturated soil. It was also observed that within the axial strain range of 0–2 %, there was unusual behavior of a temporary sudden dip in the axial stress, which was more perceivable for samples having a high value of initial matric suction.

Threats, truths and strategies: The overlooked relationship between protests, nation branding and public diplomacy

AbstractAlthough protests are an essential part of modern politics, scholars in nation branding, public diplomacy and soft power have had very little to say about these episodes. Discussions in the field have only marginally addressed dissent and disruption, falling into a methodological statism that emphasises what states do to construct and legitimise specific versions of national identity. Debates on nation promotion consequently overlook how individuals and organisations outside the state and outside national boundaries can be equally important in the construction and communication of national images. Drawing on domestic and foreign news coverage of protests in Brazil, Romania and Chile, we propose three frames to analyse the relationship between protests and nation promotion: (1) protests as threats, (2) protests as expression of the true nation and (3) protests as strategic communications. These frames shed light on how bottom‐up efforts contest—overtly or covertly—state‐sponsored versions of national identity and how protests are visibility arenas where competing discourses about the nation are communicated. Protests should therefore be acknowledged not as mere disruptions to national images or reputations but as another expression of the contingent, multifaceted and shifting nature of nationhood, particularly in highly mediatised contemporary societies.

Autonomous healing of fatigue cracks via cold welding.

Fatigue in metals involves gradual failure through incremental propagation of cracks under repetitive mechanical load. In structural applications, fatigue accounts for up to 90% of in-service failure1,2. Prevention of fatiguerelies on implementation of large safety factors and inefficient overdesign3. In traditional metallurgical design for fatigue resistance, microstructures are developed to either arrest or slow the progression of cracks. Crack growth is assumed to be irreversible. By contrast, in other material classes, there is a compelling alternative based on latent healing mechanisms and damage reversal4-9. Here, we report that fatigue cracks in pure metals can undergo intrinsic self-healing. We directly observe the early progression of nanoscale fatigue cracks, and as expected, the cracks advance, deflect and arrest at local microstructural barriers. However, unexpectedly, cracks were also observed to heal by a process that can be described as crack flank cold welding induced by a combination of local stress state and grain boundary migration. The premise that fatigue cracks can autonomously heal in metals through local interaction with microstructural features challenges the most fundamental theories on how engineers design and evaluate fatigue life in structural materials. We discuss the implications for fatigue in a variety of service environments.