A Hybrid Visual Tracking Algorithm Based on SOM Network and Correlation Filter

To meet the challenge of video target tracking, based on a self-organization mapping network (SOM) and correlation filter, a long-term visual tracking algorithm is proposed. Objects in different videos or images often have completely different appearance, therefore, the self-organization mapping neural network with the characteristics of signal processing mechanism of human brain neurons is used to perform adaptive and unsupervised features learning. A reliable method of robust target tracking is proposed, based on multiple adaptive correlation filters with a memory function of target appearance at the same time. Filters in our method have different updating strategies and can carry out long-term tracking cooperatively. The first is the displacement filter, a kernelized correlation filter that combines contextual characteristics to precisely locate and track targets. Secondly, the scale filters are used to predict the changing scale of a target. Finally, the memory filter is used to maintain the appearance of the target in long-term memory and judge whether the target has failed to track. If the tracking fails, the incremental learning detector is used to recover the target tracking in the way of sliding window. Several experiments show that our method can effectively solve the tracking problems such as severe occlusion, target loss and scale change, and is superior to the state-of-the-art methods in the aspects of efficiency, accuracy and robustness.

Extreme Precipitation in the Eastern Mediterranean in ERA5

<p><span>Datasets with precipitation indices from the coastal areas of Syria, Lebanon and Israel are defined from the ERA5-Land database (0.1° resolution). In each coastal area the grid point with the highest hourly precipitation is selected. The declustered datasets are modelled by generalised Pareto distribution. The parameters of the stationary models are estimated using the maximum likelihood (MLE) and Bayesian inference methods. </span><span></span></p><p><span>Non-stationary models with several different covariates, i.e., time and teleconnection indices are incorporated into the scale parameter. The parameters of the non-stationary models are estimated using the MLE. The goodness-of-fit of stationary models is assessed by the Anderson-Darling test. QQ-plots subjectively assess the goodness-of-fit for both stationary and non-stationary models. The goodness-of-fit of non-stationary models is assessed in comparison to the stationary models with the likelihood ratio test (LRT) and with the differences in the Akaike information criterion (AIC). </span><span></span></p><p><span>The results show clear non-stationarity with the time covariates. Non-stationarity with teleconnection covariates is incoherent, except for the North Atlantic oscillation (NAO) in Syria. Return levels are estimated for stationary and non-stationary models which are obtained from different quantiles of the time-changing scale parameter vector according to -risk scenarios. The results show that return levels are highest in Syria and lowest in Israel.</span></p>

Simple Analytic Solutions for a Convectively Driven Walker Circulation and Their Relevance to Observations

We present a linear equation for the Walker circulation streamfunction and find its analytic solutions given specified convective heating. In a linear Boussinesq fluid with Rayleigh damping and Newtonian cooling, the streamfunction obeys a Poisson’s equation, forced by gradients in the meridionally averaged diabatic heating and Coriolis force. For an idealized convective heating distribution, analytic solutions for the streamfunction can be found through an analogy with electrostatics. We use these solutions to study the response of the Walker circulation strength (mass transport) to changes in the vertical and zonal scales of convective heating. Robust responses are obtained that depend on how the total convective heating of the atmosphere responds to changing scale. If the total heating remains unchanged, increasing the zonal scale or the vertical scale always leads to a weaker circulation. Conversely, if the total heating grows in proportion to the spatial scale, the circulation becomes stronger with increasing scale. These conclusions are shown to be consistent with a three-dimensional numerical model. Moreover, they are useful in describing the observed seasonal and interannual (ENSO) variability of the Indo-Pacific Walker circulation. On both time scales, the overturning becomes weaker with increasing zonal scale of the convective region, reminiscent of our solutions where we do not vary the total convective heating. Reanalysis data also indicate that the zonal circulation is quite strongly damped, thus yielding a result that the circulation strength is directly proportional to the warm-pool spatial-mean precipitation.

A changing environment of urban education: historical and spatial analysis of private supplementary tutoring in China

Recent decades have brought dramatic urbanization to China. Between 1978 and 2018, the urban population rose from 17.9 per cent to 59.6 per cent of the total. Urbanization has many implications, including for education. China’s government has long been concerned about imbalances in access to and quality of schooling, and new imbalances have been introduced through market forces in the so-called shadow education sector of private supplementary tutoring, arising from both demand and supply. Urban families in particular seek private supplementary tutoring, and tutorial companies favour densely populated areas for higher enrolments. China has the world’s largest school system and most extensive shadow provision. This paper conceptualizes the space of shadow provision in educational, social and geographical terms. It highlights the changing scale and nature of private tutoring, observes the roles of new technologies and government regulations, notes the impact of COVID-19, and argues that shadow education both shapes and is shaped by urbanization.

Immigrants in the Republic of Poland after 1989 and economic security of the state in the context of the provisions of selected strategic documents

The article aims to assess the impact of the increasing scale of economic immigration into the Republic of Poland after 1989 on the level of economic security of the state. The study indicates and describes the most significant moments influencing the changing scale of immigration to Poland after 1989, and analyses selected strategic documents on security related to the phenomenon of economic immigration. Qualitative research methods were adopted, including analysis of sources, using the technique of analyzing the content of Polish and foreign literature, Polish strategic documents, legal acts, and statistical data (desk research) of the Office for Foreigners to achieve the objective.

Solving Kepler’s equation with CORDIC double iterations

ABSTRACT In previous work, we developed the idea to solve Kepler’s equation with a CORDIC-like algorithm, which does not require any division, but still requires multiplications in each iteration. Here we overcome this major shortcoming and solve Kepler’s equation using only bitshifts, additions and one initial multiplication. We prescale the initial vector with the eccentricity and the scale correction factor. The rotation direction is decided without correction for the changing scale. We find that double CORDIC iterations are self-correcting and compensate for possible wrong rotations in subsequent iterations. The algorithm needs 75 per cent more iterations and delivers the eccentric anomaly and its sine and cosine terms times the eccentricity. The algorithm can also be adopted for the hyperbolic case. The new shift-and-add algorithm brings Kepler’s equation close to hardware and allows it to be solved with cheap and simple hardware components.

An Empirical Study on the Impact of Foreign Strategic Investment on Banking Sustainability in China

In order to improve the banking sustainability in China, China’s government has announced that the restrictions on foreign shareholding ratio in domestic banks will be canceled. However, the effectiveness of foreign strategic investment needs checking. In addition, under the new policy, the method by which banks formulate appropriate internal decisions about introducing foreign strategic investment is an important issue for bank managers. Continuous productivity growth will bring sustainable development; therefore, the aims of this paper are: (1) to find the relationship between foreign strategic investment and productivity change of China’s banks, and to verify the effectiveness of introducing foreign strategic investment; (2) to find the optimal foreign shareholding ratio; (3) to show how foreign strategic investment affects the productivity of China’s banks, i.e. the transmission mechanism between them, and to provide bank managers with evidence and support for making decisions on introduction of foreign strategic investment. This paper employs the Malmquist-Luenberger index and combines it with Epsilon-based-measure to derive a new index, i.e. the EBM-Malmquist-Luenberger index, to measure the dynamic productivity change of China’s banks. In addition, the dynamic panel data and system GMM estimator are used to analyze the transmission mechanism as well as the impact of foreign strategic investment on the productivity of China’s banks. The results revealed three facts. First, when the foreign shareholding ratio increases within a given range, foreign strategic investment continuously improves the productivity and sustainability of China’s banks. Second, an inverse N-shaped relation between foreign strategic investment and productivity growth of China’s banks is supported, and the optimal foreign shareholding ratio is 20.16%. Last but not least, foreign strategic investment improves the productivity and sustainability of China’s banks, mainly through changing scale efficiency. The results of this paper may provide support for policy formulation of China’s banks.

Stretching scales? Risk and sociality in climate finance

The heterodox literature on financial risk has in recent years focused predominantly on how risk is distributed, and on the market instabilities and social inequalities that different risk distributions seed. Typically much less discussed is the constitution of financial risk, which is this article’s concern. Drawing empirical examples from two climate financial instruments, its particular interest is in the changing scale – social, spatial and temporal – of the “risk pools” associated with different financial products: the populations across which the products in question serve to aggregate underlying risk. The article explores how, against a historical backdrop of four decades of scale compression in the shape of risk individualization under neoliberalism, certain novel climate financial products seemingly indicate a contrary stretching of the risk pool. The article critically examines sovereign catastrophe insurance pools and green (climate) bonds, highlighting both the significance of the stretching that they effect but also the tensions and limits apparent in this emergent dynamic.