407 research outputs found
Coordinated planning of charging swapping stations and active distribution network based on EV spatial-temporal load forecasting
Electric vehicles (EVs) charging swapping stations (CSSs), as well as multi-functional integrated charging and swapping facilities (CSFs), have become important to reduce the impact of e-mobility on the electric power distribution system. This paper presents a coordinated planning optimization strategy for CSSs/CSFs and active distribution networks (AND) that includes distributed generation. The approach is based on the application of a specifically developed spatial-temporal load forecasting method of both plug-in EVs (PEVs) and swapping EVs (SEVs). The approach is formulated as a mathematical programming optimization model that provides the location and sizing of new CSSs, the best active distribution network topology, the required distributed generation, and substation capacities. The developed model is solved using CPLEX, and its characteristics and performances are evaluated through a realistic case study
Drought legacies in mixed Mediterranean forests: Analysing the effects of structural overshoot, functional traits and site factors
Previous favorable climate conditions stimulate tree growth making some forests more vulnerable to hotter droughts. This so-called structural overshoot may contribute to forest dieback, but there is little evidence on its relative importance depending on site conditions and tree species because of limited field data. Here, we analyzed remote sensing (NDVI) and tree-ring width data to evaluate the impacts of the 2017 drought on canopy cover and growth in mixed Mediterranean forests (Fraxinus ornus, Quercus pubescens, Acer monspessulanum, Pinus pinaster) located in southern Italy. Legacy effects were assessed by calculating differences between observed and predicted basal area increment (BAI). Overall, the growth response of the study stands to the 2017 drought was contingent on site conditions and species characteristics. Most sites presented BAI and canopy cover reductions during the drought. Growth decline was followed by a quick recovery and positive legacy effects, particularly in the case of F. ornus. However, we found negative drought legacies in some species (e.g., Q. pubescens, A. monspessulanum) and sites. In those sites showing negative legacies, high growth rates prior to drought in response to previous wet winter-spring conditions may have predisposed trees to drought damage. Vice versa, the positive drought legacy found in some F. ornus site was linked to post-drought growth release due to Q. pubescens dieback and mortality. Therefore, we found evidences of structural drought overshoot, but it was restricted to specific sites and species. Our findings highlight the importance of considering site settings such as stand composition, pre-drought conditions and different tree species when studying structural overshoot. Droughts contribute to modify the composition and dynamics in mixed forests
Molecular dynamics simulations of oxide memristors: thermal effects
We have extended our recent molecular-dynamic simulations of memristors to
include the effect of thermal inhomogeneities on mobile ionic species appearing
during operation of the device. Simulations show a competition between an
attractive short-ranged interaction between oxygen vacancies and an enhanced
local temperature in creating/destroying the conducting oxygen channels. Such a
competition would strongly affect the performance of the memristive devices.Comment: submit/0169777; 6 pages, 4 figure
Chemo-radiotherapy plus durvalumab for loco-regional relapse of resected NSCLC
Background tumor recurrence after NSCLC surgical resection is the most common cause of treatment failure that sharply reduces the patient's life expectancy. The optimal treatment strategy for loco-regional recurrences developing after surgical resection in patients with non-small-cell lung cancer (NSCLC) is not established yet. This report aims to describe the pattern of relapse, PFS, and OS in patients treated with radio-chemotherapy and durvalumab for loco-regional relapse after surgery. Methods We conducted a multicenter, retrospective study including subjects who underwent surgical resection for NSCLC and were treated with Pacific protocol after loco-regional relapse. Results Twenty-four patients met the inclusion criteria. At the time of diagnosis mean age was 65 years (range 47-78), the majority being male (58.3%). The 12-month progression-free survival rate was 68.7%, the 18-month progression-free survival rate was 45.8%, and the 24-month progression-free survival rate was 34.3%. There were three deaths: the 12-month survival rate was 91%, and the 18-month survival rate was 82.8%. Conclusions In this article, we propose a treatment strategy that might prolong post recurrence survival in patients with good performance status experiencing loco-regional relapse after surgery
О ПОВыШЕНИИ УРОВНЯ НАДЕЖНОСТИ И БЕЗОПАСНОСТИ ЗАПУСКА ПОДЗЕМНыХ ЛЕНТОЧНыХ КОНВЕЕРОВ НА ШАХТАХ "АНТРАЦИТ" И ГП "СВЕРДЛОАНТРАЦИТ"
Наведено результати досвіду застосування вакуумних контактів в низьковольтній пусковій апаратурі взабоях шахт "Комсомольська" та "ім. Ф.Е.Дзержінського" державних підприємств "Антрацит" і "Ро-венькиантрацит".Приведены результаты опыта использования вакуумних контактов в низковольтной пусковой аппара-туре в забоях шахт "Комсомольская" и "им. Ф.Э. Дзержинского" государственных предприятий "Ан-трацит" и "Ровенькиантрацит
Scattering of surface electrons by isolated steps versus periodic step arrays
We investigate the scattering of electrons belonging to Shockley states of (111)-oriented noble metal surfaces using angle-resolved photoemission (ARPES) and scanning tunneling microscopy (STM). Both ARPES and STM indicate that monatomic steps on a noble metal surface may act either as strongly repulsive or highly transmissive barriers for surface electrons, depending on the coherence of the step lattice, and irrespectively of the average step spacing. By measuring curved crystal surfaces with terrace length ranging from 30 to 180 Å, we show that vicinal surfaces of Au and Ag with periodic step arrays exhibit a remarkable wave function coherence beyond 100 Å step spacings, well beyond the Fermi wavelength limit and independently of the projection of the bulk band gap on the vicinal plane. In contrast, the analysis of transmission resonances investigated by STM shows that a pair of isolated parallel steps defining a 58 Å wide terrace confines and decouples the surface state of the small terrace from that of the (111) surface. We conclude that the formation of laterally confined quantum well states in vicinal surfaces as opposed to propagating superlattice states depends on the loss of coherence driven by imperfection in the superlattice order. © 2013 American Physical Society.This work was supported in part by the Spanish MICINN (MAT2007-63083 and MAT2010-15659), the Basque Government (IT-257-07), and the Agència de Gestió d’Ajuts Universitaris i de Recerca (2009 SGR 695). The SRC is funded by the National Science Foundation (Award No. DMR-0084402). A.M. and J.L.-C. acknowledge funding from the Ramon y Cajal Fellowship program.Peer Reviewe
Risk-shifting Through Issuer Liability and Corporate Monitoring
This article explores how issuer liability re-allocates fraud risk and how risk allocation may reduce the incidence of fraud. In the US, the apparent absence of individual liability of officeholders and insufficient monitoring by insurers under-mine the potential deterrent effect of securities litigation. The underlying reasons why both mechanisms remain ineffective are collective action problems under the prevailing dispersed ownership structure, which eliminates the incentives to moni-tor set by issuer liability. This article suggests that issuer liability could potentially have a stronger deterrent effect when it shifts risk to individuals or entities holding a larger financial stake. Thus, it would enlist large shareholders in monitoring in much of Europe. The same risk-shifting effect also has implications for the debate about the relationship between securities litigation and creditor interests. Credi-tors’ claims should not be given precedence over claims of defrauded investors (e.g., because of the capital maintenance principle), since bearing some of the fraud risk will more strongly incentivise large creditors, such as banks, to monitor the firm in jurisdictions where corporate debt is relatively concentrated
Paired comparisons of carbon exchange between undisturbed and regenerating stands in four managed forests in Europe
The effects of harvest on European forest net ecosystem exchange (NEE) of carbon and its photosynthetic and respiratory components (GPP (gross primary production) and TER (total ecosystem respiration)) were examined by comparing four pairs of mature/harvested sites in Europe via a combination of eddy covariance measurements and empirical modeling. Three of the comparisons represented high coniferous forestry (spruce in Britain, and pines in Finland and France), while a coppice-with-standard oak plantation was examined in Italy.
While every comparison revealed that harvesting converted a mature forest carbon sink into a carbon source of similar magnitude, the mechanisms by which this occurred were very different according to species or management practice. In Britain, Finland, and France the annual sink (source) strength for mature (clear-cut) stands was estimated at 496 (112), 138 (239), and 222 (225) g C m−2, respectively, with 381 (427) g C m−2 for the mature (coppiced) stand in Italy. In all three cases of high forestry in Britain, Finland, and France, clear-cutting crippled the photosynthetic capacity of the ecosystem – with mature (clear-cut) GPP of 1970 (988), 1010 (363), and 1600 (602) g C m−2– and also reduced ecosystem respiration to a lesser degree – TER of 1385 (1100), 839 (603), and 1415 (878) g C m−2, respectively. By contrast, harvesting of the coppice oak system provoked a burst in respiration – with mature (clear-cut) TER estimated at 1160 (2220) gC m−2– which endured for the 3 years sampled postharvest. The harvest disturbance also reduced GPP in the coppice system – with mature (clear-cut) GPP of 1600 (1420) g C m−2– but to a lesser extent than in the coniferous forests, and with near-complete recovery within a few years. Understanding the effects of harvest on the carbon balance of European forest systems is a necessary step towards characterizing carbon exchange for timberlands on large scales
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