Border Effects Research Articles

Investigation of a complete squeeze-film damping model for MEMS devices

Dynamic performance has long been critical for micro-electro-mechanical system (MEMS) devices and is significantly affected by damping. Different structural vibration conditions lead to different damping effects, including border and amplitude effects, which represent the effect of gas flowing around a complicated boundary of a moving plate and the effect of a large vibration amplitude, respectively. Conventional models still lack a complete understanding of damping and cannot offer a reasonably good estimate of the damping coefficient for a case with both effects. Expensive efforts have been undertaken to consider these two effects, yet a complete model has remained elusive. This paper investigates the dynamic performance of vibrated structures via theoretical and numerical methods simultaneously, establishing a complete model in consideration of both effects in which the analytical expression is given, and demonstrates a deviation of at least threefold lower than current studies by simulation and experimental results. This complete model is proven to successfully characterize the squeeze-film damping and dynamic performance of oscillators under comprehensive conditions. Moreover, a series of simulation models with different dimensions and vibration statuses are introduced to obtain a quick-calculating factor of the damping coefficient, thus offering a previously unattainable damping design guide for MEMS devices.

Environmental justice perspective on the distribution and determinants of polluting enterprises in Guangdong, China

With the rapid urbanization and industrialization, the uneven distribution of polluting enterprises among different socioeconomic groups has become a prominent environmental social problem in transitional China but is rarely recognized. This paper introduces environmental justice theories in industrial location studies. A heuristic analytical framework is proposed to analyze the distribution and determinants of polluting enterprises in Guangdong, China, a highly developed region but with high social and economic inequality. Polluting enterprises are mostly agglomerated in the Pearl River Delta (PRD) region with the rest in the mountainous and hilly non-PRD region. Bivariate local spatial autocorrelation analysis shows the colocation of polluting enterprises and migrants. Our regression results reveal that the county where many migrant residents are concentrated historically appears to attract many polluting firms to enter. However, less firms are found in the county with many highly educated groups and ethnic minorities. Land space planning, environmental regulation, labor costs, and agglomeration economy have driven the distribution of new polluting enterprises, whereas the influences of traffic accessibility and border effect do not work actually. To some extent, the distribution of new polluting enterprises must be recognized as a predictable result of the characteristics of prior demographic distribution.

On water-ingression during top-flooding of corium melts

In the course of severe accident in a nuclear power plant, the corium mixture may flow down in the reactor pit and start a thermal attack of the basemat concrete. A simple way to terminate the melt progression may be to add water on top of it. Among the various physical processes that may participate in the quenching, water may penetrate into the solidified corium through cracks generated by the thermal stress during the solidification.The present paper aims at providing a clarification of the process though an analysis of the few dedicated experimental data available using proto-typical corium, namely the SSWICS 1-7 experiments. At first, a general reminder and analysis of the data is given. Then, the thermal-hydraulic aspects are investigated through the construction of a dedicated heat flux correlation and its use via the experimentally measured post-test permeabilities. The analysis is supported by 1D and 2D evaluations with the multiphase flow code MC3D-PREMIX, slightly modified for the purpose. It is concluded that the heat flux drastically decreases with the amount of added concrete material. Furthermore, 2D border effects are investigated and their importance highlighted in view of the experimental results analysed. These effects should explain the absence of observation of water ingression heat flux in the cases with large concrete amounts. Following, the paper proposes a model for the created permeability. Due to the complexity of the process and to the large uncertainties of the needed material properties in the considered situation with very high temperatures, a semi-empirical model is derived.Lastly, the model is adapted to the situation with internal decay heat, although no open experimental data is available to precisely support any model. A complete modeling is out of the scope of the paper, hence the focus is to provide hints for a first analysis of the impact of decay heat on its coolability.

Railway and trade in modern China: Evidence from the 1930s

There are controversies on the trade promoting effect of the railroad in modern times in the existing literature. We estimate the impact of the railway on domestic trade through forward linkages using an Eaton-Kortum model with county-commodity level data in Shandong and Hunan provinces in 1933. We show that the railway significantly decreased the trade cost and improved bilateral trade in Hunan and Shandong provinces. In particular, for every 10% decrease in geographical distance, the value of bilateral trade increased by 8.98%. In addition, our results on the existence of provincial border effect in Hunan and the disappearance of it in Shandong, imply that the emergence of railway contributed to the removal of provincial border effect. Furthermore, we find that counties with railway connections had higher per capita output, especially for those with a larger manufacturing sector. Our results echo those found in Andrabi and Kuehlwein (2010) and Donaldson (2018) for British India and Pérez-Cervantes (2014) for the US.

Financial System Development in Emerging Economies: An Array of MINT Economic Bloc

This study investigated financial system development in emerging economies of Mexico, Indonesia, Nigeria and Turkey (MINT)with a view to ascertaining the level of financial institutions and markets depth, access and efficiency and intra-dependency of these financial system development indicators in member countries from 2000-2020. Comparatively, the level financial institutions and markets depth, access and efficiency in some MINT member countries were below standards for emerging economies especially in Nigeria, while some performed above the benchmark.VAR results revealed that indicators of financial system development were strongly endogenous and exogenous in the short and long run except financial institutions efficiency and financial markets depth, depicting independent influence and significant self-predictions. Based on the findings, researchers recommends that MINT monetary zone should be established to facilitate cross border effect of financial institutions and markets development in member states, and there should be common policy measure to pursue a robust financial institutions and markets development to complement and harness innovations in the different components of the financial system.

ESTIMATING BORDER EFFECTS: THE IMPACT OF SPATIAL AGGREGATION

AbstractTrade data are typically aggregated across space. In this article, we investigate the sensitivity of gravity estimation to spatial aggregation. We build a model in which micro regions are aggregated into macro regions. We then apply the model to the large literature on border effects in domestic and international trade. Our theory shows that aggregation leads to border effect heterogeneity. Larger regions and countries are systematically associated with smaller border effects. We test our theory with aggregate and industry‐level trade flows for U.S. states. Our results confirm the model's predictions, with strong heterogeneity patterns.

Integration of Dual Border Effects in Resource Estimation: A Cokriging Practice on a Copper Porphyry Deposit

Hierarchical or cascade resource estimation is a very common practice when building a geological block model in metalliferous deposits. One option for this is to model the geological domains by indicator kriging and then to estimate (by kriging) the grade of interest within the built geodomains. There are three problems regarding this. The first is that sometimes the molded geological domains are spotty and fragmented and, thus, far from the geological interpretation. The second is that the resulting estimated grades highly suffer from a smoothing effect. The third is related to the border effect of the continuous variable across the boundary of geological domains. The latter means that the final block model of the grade shows a very abrupt transition when crossing the border of two adjacent geological domains. This characteristic of the border effect may not be always true, and it is plausible that some of the variables show smooth or soft boundaries. The case is even more complicated when there is a mixture of hard and soft boundaries. A solution is provided in this paper to employ a cokriging paradigm for jointly modeling grade and geological domains. The results of modeling the copper in an Iranian copper porphyry deposit through the proposed approach illustrates that the method is not only capable of handling the mixture of hard and soft boundaries, but it also produces models that are less influenced by the smoothing effect. These results are compared to an independent kriging, where each variable is modeled separately, irrespective of the influence of geological domains.

Do political or ethnic and historical borders affect values and beliefs more? Some evidence from Central Europe

AbstractThe paper uses data from the World Values Survey and the European Values Study on individuals in Hungary and its neighbouring countries to examine the effects of political borders on different beliefs, as opposed to that of ethnic differences or historical borders. The focus on Hungary and its neighbours is explained by the fact that parts of the Hungarian ethno-linguistic community can be found in all these countries, which makes it possible to separate the effect of culture from that of the current political community. By applying a cultural gravity model which is concerned with the differences in beliefs between all possible pairs of individuals in the sample, the paper finds that out of five areas of beliefs, it is the beliefs regarding work, markets, and democracy whose differences are robustly affected by political borders, giving some support to the approach which argues that values are shaped through the dialogue occurring within a political community.*

Model-free capacitance analysis of electrodes with a 2D+1D dispersion of time constants

A constant phase element (CPE) is often used in electrochemical impedance spectroscopy to describe the non-ideal impedance of solid/electrolyte interfaces. The generalization of its mathematical description leads to the concept of a variable or generalized phase element αgpe, which, in association with Brug's expression, can be used to determine the interfacial capacitance of metallic electrodes, whose time-constant distribution is restricted to a bidimensional plane (C2D). In this work, a heuristic approach is used to extend the generalization principle even further, in order to arrive at an expression of capacitance, Cgpe, that is valid for electrodes with time-constant dispersions that also spread into the electrode bulk, causing a 2D+1D time-constant distribution. As a proof of concept, the proposed method is applied in the analysis of the electrochemical impedance of n-doped hydrogen-terminated Si(100) electrode in 100 mM Na2SO4, in a potential range that extends from accumulation to depletion. The single crystalline structure and polished surface of the electrode grants a quasi-ideal capacitive behavior to the system that allows comparison of the proposed analysis with the traditional representation of effective capacitance Ceff. Both methods yield similar results in the depletion region, where the impedance response is predominantly defined by the ideal behavior of the silicon space charge region. In accumulation, however, when impedance is influenced by the somewhat larger distribution of relaxation times of the electric double layer, Ceff shows frequency dispersion, whereas Cgpe does not. A dimensional analysis of the functional elements in Cgpe reveals the underlying reason for this intriguing behavior and also shows that C2D is, in fact, just an approximate expression of the more general Cgpe. It is also shown that the generalized capacitance representation allows for a clear detection of the onset of size border effects, and these appear at a higher frequency than what is observed in the Ceff representation.

Fuelbreak effectiveness against wind-driven and plume-dominated fires: A 3D numerical study

The effectiveness of a fuelbreak, created in a homogeneous grassland on a flat terrain, was studied numerically. The analysis relies on 3D numerical simulations that were performed using a detailed physical-fire-model (FIRESTAR3D) based on a multiphase formulation. To avoid border effects, calculations were carried out by imposing periodic boundary conditions along the two lateral sides of the computational domain, reproducing that way a quasi-infinitely long fire front. A total of 72 simulations were carried out for various wind speeds, fuel heights, and fuelbreak widths, which allowed to cover a large spectrum of fire behaviour, ranging from plume-dominated fires to wind-driven fires. The results were classified in three main categories: 1- “Propagation” if fire crossed the fuelbreak with a continuous fire front, 2- “Overshooting” and “Marginal” if fire marginally crosses the fuelbreak with the formation of burning pockets, and 3- “No propagation” if fire does not cross at all the fuelbreak. The ratio of fuelbreak width to fuel height, marking the “Propagation”/“No propagation” transition, was found to be scaled with Byram's convection number Nc as 75.07 × Nc−0.46. The numerical results were also compared to an operational wildfire engineering tool (DIMZAL) dedicated to fuelbreaks dimensioning.

Strategic interaction of environmental regulation and its influencing mechanism: Evidence of spatial effects among Chinese cities

China's central government has invested great effort into environmental protection, but the country's environmental problem remains serious. One important reason is that environmental regulations have been implemented incompletely. Hence, this paper analyzes the incomplete implementation of environmental regulation in China from the perspective of enforcement interaction among prefecture-level cites. Comparing to the existing literature, a game theory model of environmental regulation between local leaders is first built based on tournament competition, then spatial spillover effects and its influencing mechanism are further analyzed with empirical evidence. Empirical results show that strategic interaction of environmental regulation is evident among central and western cities in China, supportive of an overall ‘race to the bottom’ competition. Spatial border effect and spatial economic effect of strategic interaction are found to exist mainly for cities within the same province, and spatial economic effect is found to be dominant. Cities with younger leaders are more affected by spatial effects. But two factors, environmental one-vote-veto system, and public environmental participation, are helpful in terms of altering city leaders' behavior and alleviating the enforcement interaction of environmental regulation, thus improving the incomplete implementation of environmental regulation to an extent. The findings indicate that central government should pay attention to environmental incentives for local governments and encourage more public environmental participation.

Dancing with Epistemic Borders

This article explores an encounter with ‘unknowns’ of knowledge production and analysis experienced by a dance practitioner-scholar and social science researchers during an ongoing, collaborative project charting the effect of territorial borders on dance artists’ lives and practice. Expanding the investigation of borders beyond the territorial to also encompass the methodological, the Co-Motion: Dance and borders project experiments with how improvised dance responses to research questions place an affective and embodied experience of borders in dialogue with more traditional methods of sociological enquiry. In contrast to ‘Danced Data’ projects that position dance as a primarily interpretative and communicative tool, Co-Motion considers how dance practice can be made integral to interdisciplinary, mixed-methods research processes as a source of knowledge production in its own right. The project’s aim to achieve an interweaving of different knowledges through a possible fusion of horizons in an event generated by a joint questioning (Gadamer) seemed a relatively straightforward premise at the outset. However, the practical execution raised questions as to how a mixed-methods approach might truly embrace epistemological pluralism in knowledge production from inception, and how seemingly paradoxical forms of knowledge generation and languaging (Ingold) might be reconciled in analysis. Acknowledging these complexities, this article presents a dialogue between the researchers involved, mapping a terrain that welcomes unknowns and challenges the knowledge hegemonies experienced. Building on Mignolo and Tlostanova’s (2006) critique of Western imperial and colonial knowledge hierarchies and their concept of ‘critical border thinking’, we ask how dance troubles epistemic frontiers that place knowledge classified as other outside of discourse. We also consider what epistemic shifts need to occur in collaborative, interdisciplinary projects to enable an ‘unlearning and ungrounding of knowledge’ that allows ‘unforeseen bodies, movements and relations’ (Cvejić, 2018, p.226) to inform the design of cultural policies that impact artists’ daily lives and practice.

Bootstrap simulations for evaluating the model estimation of the extent of cross-pollination in maize at the field-scale level.

With the recent advent of genetic engineering, numerous genetically modified (GM) crops have been developed, and field planting has been initiated. In open-environment cultivation, the cross-pollination (CP) of GM crops with wild relatives, conventional crops, and organic crops can occur. This exchange of genetic material results in the gene flow phenomenon. Consequently, studies of gene flow among GM crops have primarily focused on the extent of CP between the pollen source plot and the adjacent recipient field. In the present study, Black Pearl Waxy Corn (a variety of purple glutinous maize) was used to simulate a GM-maize pollen source. The pollen recipient was Tainan No. 23 Corn (a variety of white glutinous maize). The CP rate (%) was calculated according to the xenia effect on kernel color. We assessed the suitability of common empirical models of pollen-mediated gene flow (PMGF) for GM maize, and the field border (FB) effect of the model was considered for small-scale farming systems in Asia. Field-scale data were used to construct an optimal model for maize PMGF in the maize-producing areas of Chiayi County, southern Taiwan (R.O.C). Moreover, each model was verified through simulation and by using the 95% percentile bootstrap confidence interval length. According to the results, a model incorporating both the distance from the source and the FB can have optimal fitting and predictive abilities.

Healing an abnormalised body: bringing the agency of unseen people back to the inter-Korean border

Conventional approaches to the ‘North Korea Problem’ underpin the interests of great powers and the Westphalian canon that buttresses the status quo of a divided Korea, normalising and perpetuating the abnormality of the Korean body. This article draws on a postcolonial approach to international relations and uses East Asian medicine (EAM)’s principles and epistemological underpinnings as an analytical framework to examine the effects of the inter-Korean border on Korea’s body politic and to assess the 2018 inter-Korean border crossings. I demonstrate how the inter-Korean border serves as a site that manifests a new possibility and how invisible ordinary people play an indispensable role in mending the abnormalised Korean body, defying the idea of Korea’s intractable conflict. Ultimately, this study rethinks state and non-state interactions, as well as their reciprocal and conflicting relations, in producing, perpetuating and mitigating artificial myths about inter-Korean border conflicts as a conceptual dialogue between state-centred and EAM-inspired approaches towards reconciliation processes. By drawing on the implications of escaping the Westphalian canonical nexus of power-knowledge-discourse, I suggest an alternative way of healing from inside out by de-abnormalising the inter-Korean border and (re)historicising the agency of unseen people in re-imagining the Korean body politic and world politics.

Cross-country effects and policy responses to COVID-19 in 2020: The Nordic countries

We provide a three-step analysis of the effects and responses to COVID-19 in Nordic countries (Denmark, Finland, Norway and Sweden), large Western European countries (France, Germany, Italy, Spain and United Kingdom) and OECD Europe. First, we compare public health trends over 2020 in terms of per capita COVID-19 cases, fatalities, testing and the stringency of social distancing (SD) measures. Second, in a ‘like-with-like’ policy response model between Nordic countries, we test for the effects of air border closures on the growth in per capita COVID-19 cases while accounting for differences in stringency of social distancing and other measures. Third, using data from OECD European countries, we regress percentage change in GDP (2020–2019) on cumulative per capita national COVID-19 fatalities. We find that: (1) Sweden is an outlier, relative to its Nordic neighbours, in its COVID-19 public health outcomes; (2) Sweden would have had reduced cases and fatalities if it had adopted the air border closures implemented by its Nordic neighbours in the first half of 2020; and, (3) for OECD Europe, there is a statistically significant and negative association between per capita COVID-19 fatalities and economic performance.

Environmental and Social Justice on the Border of Five Major U.S. Cities

This study examines environmental and social justice metrics on the city and suburban borders of five major U.S. cities: Chicago, Detroit, Los Angeles, Philadelphia, and New York. The author expected a marked increase in measures of social injustice at the border but not for every environmental indicator. Using the U.S. Environmental Protection Agency (EPA)s EJSCREEN tool, 18 variables were extracted for 276 circular zones with a 1-mile radius (3.14 square miles) on both sides of the city–suburb border. The analysis found expected major differences at the border in low income, formal educational achievement, and minority populations, especially in Detroit and Philadelphia. Environmental indicators were much less clearly demarcated at the borders. Ozone and lead, as expected, did not demonstrate a border effect. Localized particulates, including fine particulates, and toxic air pollutants were disproportionately concentrated on the city side of borders, and higher values moderately correlated with lower income, minority, and linguistically isolated populations. Environmental exposure at the border is lower than that at clustered concentrations around ports, industrial centers, and other densely developed locations. However, it clearly exists and needs to be included in multipronged efforts to reduce environmental injustice.

Gravity model estimates of the spatial determinants of trade, migration, and trade-and-migration policies

Using a gravity model, we explore the effects of distance and borders on trade, migration, and trade-and-migration policies and document three key differences between trade and migration patterns in otherwise equivalent specifications. Regional trade (freedom-of-movement) agreements boost trade (migration) less (more) the more distant the country pairs. Distance effects on trade (migration) decrease (are unchanged) over time. International border effects on trade (migration) decrease (are unchanged) over time.

Tree Crowns Cause Border Effects in Area-Based Biomass Estimations from Remote Sensing

The estimation of forest biomass by remote sensing is constrained by different uncertainties. An important source of uncertainty is the border effect, as tree crowns are not constrained by plot borders. Lidar remote sensing systems record the canopy height within a certain area, while the ground-truth is commonly the aboveground biomass of inventory trees geolocated at their stem positions. Hence, tree crowns reaching out of or into the observed area are contributing to the uncertainty in canopy-height–based biomass estimation. In this study, forest inventory data and simulations of a tropical rainforest’s canopy were used to quantify the amount of incoming and outgoing canopy volume and surface at different plot sizes (10, 20, 50, and 100 m). This was performed with a bottom-up approach entirely based on forest inventory data and allometric relationships, from which idealized lidar canopy heights were simulated by representing the forest canopy as a 3D voxel space. In this voxel space, the position of each voxel is known, and it is also known to which tree each voxel belongs and where the stem of this tree is located. This knowledge was used to analyze the role of incoming and outgoing crowns. The contribution of the border effects to the biomass estimation uncertainty was quantified for the case of small-footprint lidar (a simulated canopy height model, CHM) and large-footprint lidar (simulated waveforms with footprint sizes of 23 and 65 m, corresponding to the GEDI and ICESat GLAS sensors). A strong effect of spatial scale was found: e.g., for 20-m plots, on average, 16% of the CHM surface belonged to trees located outside of the plots, while for 100-m plots this incoming CHM fraction was only 3%. The border effects accounted for 40% of the biomass estimation uncertainty at the 20-m scale, but had no contribution at the 100-m scale. For GEDI- and GLAS-based biomass estimates, the contributions of border effects were 23% and 6%, respectively. This study presents a novel approach for disentangling the sources of uncertainty in the remote sensing of forest structures using virtual canopy modeling.

An adequate regulated deficit irrigation strategy improves wine astringency perception by altering proanthocyanidin composition in Cabernet Sauvignon grapes

Regulated deficit irrigation (RDI) is an agricultural practice that can enhance grapevine berry and wine quality. However, the effects of water deficit on concentration and composition of proanthocyanidins (PAs) and wine astringency are often limited and contrasting. Therefore, the profiles of PAs were investigated in Cabernet Sauvignon grown at 60% (RDI-1), 70% (RDI-2), 80% (RDI-3), and 100% (conventional irrigation, CI) of estimated evapotranspiration in 2016 and 2017. The treatments, replicated three times, were laid out in a randomized block design where any border effects were avoided. Our results showed that compared with CI, grapes grown under RDI had greater total concentrations of phenolic compounds. Skin PAs content increased in response to the RDI, especially in RDI-1 and RDI-2, while the seed PAs content was relatively insensitive to RDI. Hierarchical cluster analysis indicated that higher percentage of galloylation, molecular mass, mean degree of polymerization and the special extension subunits, such as percentage of (–)-epicatechin-3-O-gallate (%ECG) and percentage of (–)-epicatechin (%EC), led to greater astringency intensity in the wine. However, RDI-1 decreased perceived astringency due to the decreased %ECG and %EC of PAs extension subunits, and increased %ECG of PAs terminal subunits. Our study suggests that the irrigation levels at RDI-2 and RDI-3 can significantly influence the PAs compositions and improve wine astringency perception.

The border effect on mergers and acquisitions

Using a firm-level dataset of more than 500,000 domestic and cross-border mergers and acquisitions (M&As) for 95 countries during the period 1995–2015, we measure the level and evolution of the border effect on M&As. We find that the number and value of M&As between same-country firms are five times larger than between firms of different countries. We show that the border effect on the number and value of M&As remained constant during the period. The border effect on M&As in the European Union is substantially lower than elsewhere. We find that the border effect is lower for large investors and firms operating in the primary industry and utilities.