Сomparative study of arc-to-glow transition efficiency when use multilayer condensed materials in electric contacts

The paper presents and discusses results of the study of arc to glow transformation at breaking of DC inductive load of a low power (less than 10 J) and low voltage (about 250 V). The ratio in duration of arcing and glowing is investigated in dependence on circuit parameters, gas quenching medium and its pressure and in particular on contact material. The transition, to complete the study, was analyzed also by means of fast photography and radiation spectra measurements. On the basis of the results the conclusions on possibility of control of the arc to glow transformation, for practical use in low power contact switching devices, are formulated.Представлено і обговорено результати дослідження дуги, що горить, при відключенні постійного струму з індуктивним навантаженням малої потужності (менше 10 Дж) і низької напруги (біля 250 В). Відношення тривалості горіння дуги і жевріючого розряду досліджується в залежності від параметрів ланцюга, виду гасильного газу та його тиску і, головним чином, від контактного матеріалу. Для повноти дослідження змінення типу розряду аналізували також за допомогою швидкісної зйомки і вимірювання спектрів випромінювання. На основі одержаних результатів сформульовано висновки про можливість практичного застосування контролю переходу дуги в жевріючий розряд в малопотужних контактах комутуючих пристроїв.Представлены и обсуждены результаты исследования дуги, горящей при отключении постоянного тока с индуктивной нагрузкой малой мощности (менее 10 Дж) и низкого напряжения (около 250 В). Отношение продолжительности горения дуги и тлеющего разряда исследовано в зависимости от параметров цепи, вида гасящего газа и его давления и, главным образом, от контактного материала. Для полноты исследования смену типа разряда анализировали также с помощью скоростной съемки и измерения спектров излучения. На основании полученных результатов сформулированы выводы о возможности практического использования контроля перехода дуги в тлеющий разряд в маломощных контактах коммутирующих устройств

Statistical Diagnostics of Metastatic Involvement of Regional Lymph Nodes

The method of statistical classification with indicating patients that require more detailed diagnostics is proposed and analysed

Detection of Microorganisms Onboard the International Space Station Using an Electronic Nose

Abstract We report on the detection of microorganisms onboard the International Space Station (ISS) using an electronic nose we named the E-Nose. The E-Nose, containing an array of ten different metal oxide gas sensors, was trained on Earth to detect the four most abundant microorganisms that are known to exist onboard the ISS. To assess its performance in space, the E-Nose was brought to the ISS and three measurement campaigns were carried out in three different locations inside the ISS during a 5-month mission. At the end of this mission, all investigated locations were wiped with swabs, and the swabs and odor sensor signal data were sent back to Earth for an in-depth analysis in earthbound laboratories. The in-space measurements were compared with an odor database containing four organisms, but a consensus odor could not be identified. Microbiological results could not provide clues to the smell that was measured. The yeast Rhodotorula mucilaginosa was identified in the literature as the most probable candidate for the unknown odor. Further investigations showed that the smell of Rhodotorula mucilaginosa matches very well with the data obtained inside the ISS. Finally, Rhodotorula mucilaginosa DNA was identified in swabs taken from the sleeping cabin of the astronaut, which confirms the assumption that the yeast Rhodotorula mucilaginosa was actually measured in space by the E-Nose

ВЕКТОРНАЯ ЦЕПЬ МАРКОВА С ЧАСТИЧНЫМИ СВЯЗЯМИ И СТАТИСТИЧЕСКИЕ ВЫВОДЫ О ЕЕ ПАРАМЕТРАХ

A new mathematical model of discrete time series is proposed. It is called homogenous vector Markov chain of the order s with partial connections. The conditional probability distribution for this model is determined only by a few components of previous vector states. Probabilistic properties of the model are given: ergodicity conditions and conditions under which the stationary probability distribution is uniform. Consistent statistical estimators for model parameters are constructed.Предложена новая малопараметрическая модель дискретных временных рядов – однородная векторная цепь Маркова s-го порядка с частичными связями, для которой условное распределение вероятностей определяется лишь некоторыми компонентами предыдущих векторов-состояний. Установлены вероятностные свойства модели:  критерий эргодичности, условия, при которых стационарное распределение  вероятностей является равномерным. Построены состоятельные статистические оценки параметров модели

Электрофизиологическое ремоделирование правого желудочка при экспериментальной сердечной недостаточности различной этиологии

The aim of the study was to evaluate electrophysiological remodeling of the right ventricle in rats in experimental heart failure of different etiologies. Materials and methods. Isadrin-, doxorubicin- and monocrotaline-induced heart failure models were developed. Unipolar epicardial electrograms of the ventricles (256 recording sites) were recorded using a 144-channel system. The cardiac output and pressure in both ventricles of the heart were measured. Activation-recovery intervals were used as an index of duration of local repolarization, and the general and local dispersions of activation-recovery intervals were used as an index of heterogeneity of ventricular repolarization. Results. In all models of heart failure, the following were identified: 1) non-uniform prolongation of repolarization with the greatest elongation at the apex of the right ventricle; 2) an increase in apicobasal differences of repolarization with the greatest change in the right ventricle; 3) an increase in the heterogeneity of the repolarization of the epicardial layer of the ventricles with heterogeneous changes in the local heterogeneity of repolarization and a decrease in the interregional differences in the heterogeneity of the electrophysiological properties of the myocardium; 4) more pronounced changes in the repolarization of the right ventricle than in the repolarization of the left ventricle. Conclusion. Thus, irrespective of the cause of the heart failure, the following changes occur: 1) prolongation of the right ventricular repolarization occurs non-uniformly (mostly due to the apical area), which results in an increase in the right ventricular repolarization heterogeneity; 2) an increase in the heterogeneity of right ventricular repolarization is observed, which causes an increase in the overall heterogeneity of the ventricular epicardial surface. Целью работы явилась оценка электрофизиологического ремоделирования правого желудочка крыс с экспериментальной сердечной недостаточностью различной этиологии.Материалы и методы. Проводили экспериментальное моделирование изадрин-, доксорубицин- и монокроталин-индуцированной сердечной недостаточности. Униполярные эпикардиальные электрограммы желудочков (256 точек регистрации) регистрировали с помощью 144-канальной системы. Измеряли сердечный выброс и давление в обоих желудочках сердца. Вычисляли интервалы «активация – восстановление» как показатель длительности локальной реполяризации, а также определяли общую и локальную дисперсию интервалов «активация – восстановление» для оценки гетерогенности реполяризации желудочков. Результаты. Во всех моделях сердечной недостаточности выявлены: 1) неоднородная пролонгация реполяризации с наибольшим удлинением на верхушке правого желудочка; 2) увеличение апикобазальных различий реполяризации с наибольшим изменением на правом желудочке; 3) увеличение гетерогенности реполяризации эпикардиального слоя желудочков при неоднородных изменениях локальной гетерогенности реполяризации и уменьшение межрегиональных различий неоднородности электрофизиологических свойств миокарда; 4) более выраженные изменения в реполяризации правого желудочка, чем в реполяризации левого желудочка. Заключение. Независимо от причины развития сердечной недостаточности происходит неравномерное увеличение длительности реполяризации эпикардиальной поверхности (в большей степени за счет верхушки) и наблюдается усиление гетерогенности реполяризации правого желудочка, что является причиной роста общей гетерогенности реполяризации эпикардиальной поверхности желудочков в целом

Requirements for a global data infrastructure in support of CMIP6

The World Climate Research Programme (WCRP)’s Working Group on Climate Modelling (WGCM) Infrastructure Panel (WIP) was formed in 2014 in response to the explosive growth in size and complexity of Coupled Model Intercomparison Projects (CMIPs) between CMIP3 (2005–2006) and CMIP5 (2011–2012). This article presents the WIP recommendations for the global data infrastruc- ture needed to support CMIP design, future growth, and evolution. Developed in close coordination with those who build and run the existing infrastructure (the Earth System Grid Federation; ESGF), the recommendations are based on several principles beginning with the need to separate requirements, implementation, and operations. Other im- portant principles include the consideration of the diversity of community needs around data – a data ecosystem – the importance of provenance, the need for automation, and the obligation to measure costs and benefits. This paper concentrates on requirements, recognizing the diversity of communities involved (modelers, analysts, soft- ware developers, and downstream users). Such requirements include the need for scientific reproducibility and account- ability alongside the need to record and track data usage. One key element is to generate a dataset-centric rather than system-centric focus, with an aim to making the infrastruc- ture less prone to systemic failure. With these overarching principles and requirements, the WIP has produced a set of position papers, which are summa- rized in the latter pages of this document. They provide spec- ifications for managing and delivering model output, includ- ing strategies for replication and versioning, licensing, data quality assurance, citation, long-term archiving, and dataset tracking. They also describe a new and more formal approach for specifying what data, and associated metadata, should be saved, which enables future data volumes to be estimated, particularly for well-defined projects such as CMIP6. The paper concludes with a future facing consideration of the global data infrastructure evolution that follows from the blurring of boundaries between climate and weather, and the changing nature of published scientific results in the digital age

Half a degree additional warming, prognosis and projected impacts (HAPPI): Background and experimental design

Abstract. The Intergovernmental Panel on Climate Change (IPCC) has accepted the invitation from the UNFCCC to provide a special report on the impacts of global warming of 1.5 °C above pre-industrial levels and on related global greenhouse-gas emission pathways. Many current experiments in, for example, the Coupled Model Inter-comparison Project (CMIP), are not specifically designed for informing this report. Here, we document the design of the half a degree additional warming, projections, prognosis and impacts (HAPPI) experiment. HAPPI provides a framework for the generation of climate data describing how the climate, and in particular extreme weather, might differ from the present day in worlds that are 1.5 and 2.0 °C warmer than pre-industrial conditions. Output from participating climate models includes variables frequently used by a range of impact models. The key challenge is to separate the impact of an additional approximately half degree of warming from uncertainty in climate model responses and internal climate variability that dominate CMIP-style experiments under low-emission scenarios.Large ensembles of simulations (&gt;  50 members) of atmosphere-only models for three time slices are proposed, each a decade in length: the first being the most recent observed 10-year period (2006–2015), the second two being estimates of a similar decade but under 1.5 and 2 °C conditions a century in the future. We use the representative concentration pathway 2.6 (RCP2.6) to provide the model boundary conditions for the 1.5 °C scenario, and a weighted combination of RCP2.6 and RCP4.5 for the 2 °C scenario. </jats:p

Contrasting responses of mean and extreme snowfall to climate change

Snowfall is an important element of the climate system, and one that is expected to change in a warming climate. Both mean snowfall and the intensity distribution of snowfall are important, with heavy snowfall events having particularly large economic and human impacts. Simulations with climate models indicate that annual mean snowfall declines with warming in most regions but increases in regions with very low surface temperatures. The response of heavy snowfall events to a changing climate, however, is unclear. Here I show that in simulations with climate models under a scenario of high emissions of greenhouse gases, by the late twenty-first century there are smaller fractional changes in the intensities of daily snowfall extremes than in mean snowfall over many Northern Hemisphere land regions. For example, for monthly climatological temperatures just below freezing and surface elevations below 1,000 metres, the 99.99th percentile of daily snowfall decreases by 8% in the multimodel median, compared to a 65% reduction in mean snowfall. Both mean and extreme snowfall must decrease for a sufficiently large warming, but the climatological temperature above which snowfall extremes decrease with warming in the simulations is as high as −9 °C, compared to −14 °C for mean snowfall. These results are supported by a physically based theory that is consistent with the observed rain–snow transition. According to the theory, snowfall extremes occur near an optimal temperature that is insensitive to climate warming, and this results in smaller fractional changes for higher percentiles of daily snowfall. The simulated changes in snowfall that I find would influence surface snow and its hazards; these changes also suggest that it may be difficult to detect a regional climate-change signal in snowfall extremes.National Science Foundation (U.S.) (Grant AGS-1148594)United States. National Aeronautics and Space Administration (ROSES Grant 09-IDS09-0049

A novel method to improve temperature simulations of general circulation models based on ensemble empirical mode decomposition and its application to multi-model ensembles

A novel method based on the ensemble empirical mode decomposition (EEMD) method was developed to improve model performance. This method was evaluated by applying it to global surface air temperatures, which were simulated by eight general circulation models from the Coupled Model Intercomparison Project Phase 5 (CMIP5). The temperature simulations of the eight models were separated into their different components by EEMD. The model's performance improved after the first high-frequency component was removed from the original simulations by EEMD for each model, on both the global and continental scale. Moreover, EEMD was more effective in improving the model's performance compared to the wavelet transform method. The multi-model ensembles (MMEs) were calculated based on the EEMD-improved model simulations using the Average Ensemble Mean, Multiple Linear Regression, Singular Value Decomposition and Bayesian Model Averaging methods. The results showed that the MME forecasts performed better when the calculations were based on the EEMD-improved simulations as opposed to the original simulations on both the global and continental scale. Therefore, the results of the MME were further improved by using the EEMD-improved model simulations. This new method provides a simple way to improve model performance and can be easily applied to further improve MME simulations

Spatial distribution estimation of malaria in northern China and its scenarios in 2020, 2030, 2040 and 2050

© 2016 The Author(s). Background: Malaria is one of the most severe parasitic diseases in the world. Spatial distribution estimation of malaria and its future scenarios are important issues for malaria control and elimination. Furthermore, sophisticated nonlinear relationships for prediction between malaria incidence and potential variables have not been well constructed in previous research. This study aims to estimate these nonlinear relationships and predict future malaria scenarios in northern China. Methods: Nonlinear relationships between malaria incidence and predictor variables were constructed using a genetic programming (GP) method, to predict the spatial distributions of malaria under climate change scenarios. For this, the examples of monthly average malaria incidence were used in each county of northern China from 2004 to 2010. Among the five variables at county level, precipitation rate and temperature are used for projections, while elevation, water density index, and gross domestic product are held at their present-day values. Results: Average malaria incidence was 0.107 per annum in northern China, with incidence characteristics in significant spatial clustering. A GP-based model fit the relationships with average relative error (ARE) = 8.127 % for training data (R2 = 0.825) and 17.102 % for test data (R2 = 0.532). The fitness of GP results are significantly improved compared with those by generalized additive models (GAM) and linear regressions. With the future precipitation rate and temperature conditions in Special Report on Emission Scenarios (SRES) family B1, A1B and A2 scenarios, spatial distributions and changes in malaria incidences in 2020, 2030, 2040 and 2050 were predicted and mapped. Conclusions: The GP method increases the precision of predicting the spatial distribution of malaria incidence. With the assumption of varied precipitation rate and temperature, and other variables controlled, the relationships between incidence and the varied variables appear sophisticated nonlinearity and spatially differentiation. Using the future fluctuated precipitation and the increased temperature, median malaria incidence in 2020, 2030, 2040 and 2050 would significantly increase that it might increase 19 to 29 % in 2020, but currently China is in the malaria elimination phase, indicating that the effective strategies and actions had been taken. While the mean incidences will not increase even reduce due to the incidence reduction in high-risk regions but the simultaneous expansion of the high-risk areas