Individual Topology Structure of Eye Movement Trajectories

Traditionally, extracting patterns from eye movement data relies on statistics of different macro-events such as fixations and saccades. This requires an additional preprocessing step to separate the eye movement subtypes, often with a number of parameters on which the classification results depend. Besides that, definitions of such macro events are formulated in different ways by different researchers. We propose an application of a new class of features to the quantitative analysis of personal eye movement trajectories structure. This new class of features based on algebraic topology allows extracting patterns from different modalities of gaze such as time series of coordinates and amplitudes, heatmaps, and point clouds in a unified way at all scales from micro to macro. We experimentally demonstrate the competitiveness of the new class of features with the traditional ones and their significant synergy while being used together for the person authentication task on the recently published eye movement trajectories dataset

Zonal aspects of the influence of forest cover change on runoff in northern river basins of Central Siberia

Background Assessment of the reasons for the ambiguous influence of forests on the structure of the water balance is the subject of heated debate among forest hydrologists. Influencing the components of total evaporation, forest vegetation makes a significant contribution to the process of runoff formation, but this process has specific features in different geographical zones. The issues of the influence of forest vegetation on river runoff in the zonal aspect have not been sufficiently studied. Results Based on the analysis of the dependence of river runoff on forest cover, using the example of nine catchments located in the forest-tundra, northern and middle taiga of Northern Eurasia, it is shown that the share of forest cover in the total catchment area (percentage of forest cover, FCP) has different effects on runoff formation. Numerical experiments with the developed empirical models have shown that an increase in forest cover in the catchment area in northern latitudes contributes to an increase in runoff, while in the southern direction (in the middle taiga) extensive woody cover of catchments “works” to reduce runoff. The effectiveness of geographical zonality in regards to the influence of forests on runoff is more pronounced in the forest-tundra zone than in the zones of northern and middle taiga. Conclusion The study of this problem allowed us to analyze various aspects of the hydrological role of forests, and to show that forest ecosystems, depending on environmental conditions and the spatial distribution of forest cover, can transform water regimes in different ways. Despite the fact that the process of river runoff formation is controlled by many factors, such as temperature conditions, precipitation regime, geomorphology and the presence of permafrost, the models obtained allow us to reveal general trends in the dependence of the annual river runoff on the percentage of forest cover, at the level of catchments. The results obtained are consistent with the concept of geographic determinism, which explains the contradictions that exist in assessing the hydrological role of forests in various geographical and climatic conditions. The results of the study may serve as the basis for regulation of the forest cover of northern Eurasian river basins in order to obtain the desired hydrological effect depending on environmental and economic conditions

New look at understanding hydrological role of forest

The article is concerned with the discussion of the reasons for the contradictions existing in the assessment of the hydrological role of forests. The authors believe that the accumulation of new information related to seemingly well-studied processes and phenomena necessitates revisions of traditional views and leads to new knowledge of the hydrological role of forests. Various conceptual approaches to assessing the hydrological role of forests in different geographic conditions are considered. System analysis of the materials obtained by the authors and literature data made it possible to identify the features of the hydrological cycle depending on the structure of forests and climatic conditions. The data of 460 snow surveys in the period of maximum snow reserves in 212 forest stands growing in different climatic and ecological conditions were used. The comparison of the features of snow moisture balance of the forest and treeless ecosystems in different climatic conditions contributed to understanding the reasons for the contradictory assessments of the hydrological role of forests. The authors showed that in the conditions of mild and warm winters, forests are more powerful evaporators of snow moisture than treeless sites and in conditions of severe winters with frequent snowstorms, they are the accumulators of snow moisture and sources of river flow. The paper presents a conceptual model describing the mechanisms of water cycle in the forests of the boreal zone, which determine the features of the influence of forest ecosystems on the river runoff depending on the geophysical background

Transition to Sustainable Forest Management in Russia: theoretical and methodological backgrounds (In Russian)

The paper contains a short analysis of theoretical and methodological backgrounds of transition to sustainable forest management in Russia (SFM). It is concisely considered the current state of forest management in Russia which is estimated as critical; expected impacts of climate change on the country’s forests; and theoretical and methodological prerequisites, specifics and risks of transition to SFM including 1) concept and general methodological basis of transition to SFM; 2) specifics of the required information; 3) problem of forest protection in conditions of growing risks; 4) strategic prerequisites of adaptation of forests to climate change and their use as a tool of climate change mitigation; and 5) necessity of a harmonized estimation of diversity of resources and other forest ecosystem services within the paradigm of risk resilient forest management. A crucial role of models of different complexity and destination is considered as a basic methodological tool of long-term planning of forest management actions. It is shown that there is no single strategy, which would allow reaching all goals of SFM. The scale of objects within which SFM is implemented might play a crucial role in finding the optimal decisions. Similar to many other countries, Russia is late with consideration and implementation of SFM. The paper is limited by theoretical and methodological questions and does not touch upon managerial, institutional and political problems of the up-to-date forest sector of Russia

Measurement of J/ψ→γηcJ/\psi\to\gamma\eta_{\rm c} decay rate and ηc\eta_{\rm c} parameters at KEDR

Using the inclusive photon spectrum based on a data sample collected at the $J/\psi$ peak with the KEDR detector at the VEPP-4M $e^+e^-$ collider, we measured the rate of the radiative decay $J/\psi\to\gamma\eta_{\rm c}$ as well as $\eta_{\rm c}$ mass and width. Taking into account an asymmetric photon lineshape we obtained $\Gamma^0_{\gamma\eta_{\rm c}}=2.98\pm0.18 \phantom{|}^{+0.15}_{-0.33}$ keV, $M_{\eta_{\rm c}} = 2983.5 \pm 1.4 \phantom{|}^{+1.6}_{-3.6}$ MeV/$c^2$, $\Gamma_{\eta_{\rm c}} = 27.2 \pm 3.1 \phantom{|}^{+5.4}_{-2.6}$ MeV.Comment: 6 pages, 3 figure

Precise measurement of RudsR_{\text{uds}} and RR between 1.84 and 3.72 GeV at the KEDR detector

The present work continues a series of the KEDR measurements of the $R$ value that started in 2010 at the VEPP-4M $e^+e^-$ collider. By combining new data with our previous results in this energy range we measured the values of $R_{\text{uds}}$ and $R$ at nine center-of-mass energies between 3.08 and 3.72 GeV. The total accuracy is about or better than $2.6\%$ at most of energy points with a systematic uncertainty of about $1.9\%$. Together with the previous precise $R$ measurement at KEDR in the energy range 1.84-3.05 GeV, it constitutes the most detailed high-precision $R$ measurement near the charmonium production threshold.Comment: arXiv admin note: text overlap with arXiv:1610.02827 and substantial text overlap with arXiv:1510.0266

Measurement of J/psi to eta_c gamma at KEDR

We present a study of the inclusive photon spectra from 5.9 million J/psi decays collected with the KEDR detector at the VEPP-4M e+e- collider. We measure the branching fraction of radiative decay J/psi to eta_c gamma, eta_c width and mass. Our preliminary results are: M(eta_c) = 2979.4+-1.5+-1.9 MeV, G(eta_c) = 27.8+-5.1+-3.3 MeV, B(J/psi to eta_c gamma) = (2.34+-0.15+-0.40)%.Comment: To be published in Proceedings of the PhiPsi09, Oct. 13-16, 2009, Beijing, Chin

Measurement of B(J/psi->eta_c gamma) at KEDR

We present a study of the inclusive photon spectrum from 6.3 million J/psi decays collected with the KEDR detector at the VEPP-4M e+e- collider. We measure the branching fraction of the radiative decay J/psi -> eta_c gamma, eta_c width and mass. Taking into account an asymmetric photon line shape we obtain: M(eta_c) = (2978.1 +- 1.4 +- 2.0) MeV/c^2, Gamma(eta_c) = (43.5 +- 5.4 +- 15.8) MeV, B(J/psi->eta_c gamma) = (2.59 +- 0.16 +- 0.31)%$.Comment: 6 pages, 1 figure. To be published in the proceedings of the 4th International Workshop on Charm Physics (Charm2010), October 21-24, 2010, IHEP, Beijin