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SAGeLogE: A Decision Support System for Students’ Accommodation Management
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作者 Rôlin Gabriel Rasoanaivo Pascale Zaraté 《Journal of Computer and Communications》 2024年第3期107-145,共39页
SAGeLogE is the acronym of “Système d’Aide à la Gestion de Logements étudiants” which means student accommodation management support system. It’s a multi-criteria decision support system designed to... SAGeLogE is the acronym of “Système d’Aide à la Gestion de Logements étudiants” which means student accommodation management support system. It’s a multi-criteria decision support system designed to manage accommodation allocation for university students. Within SAGeLogE we developed the “Minimum of Ranks” (MIRA) aggregation method. MIRA method involves the application of multi-criteria decision-making methods (MCDM) to initially obtain different ranking. Thus, we chose the Weighted Sum Method (WSM), Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) and Combined Compromise Solution (CoCoSo) methods to be implemented in SAGeLogE. To prioritize the weights of criteria, the Anality Hierarchy Process (AHP) method was used. The interest of using the MIRA method was to obtain a compromised ranking coming from these three multi-criteria decision-making methods (WSM, TOPSIS, CoCoSo). So, we know that the accommodation to be allocated to students is always lower than the number of accommodation requests received by the organization. Thus, SAGeLogE proposed a technique that makes it easier to select students ranked by the multi-criteria decision-making and MIRA methods according to a method of calculation of quota of available accommodations within university residences. Finally, university accommodation managers had a wide choice of student ranking according to the methods implemented in SAGeLogE. The SAGeLogE experiment was carried out on the site of Toamasina University in Madagascar for an academic year with 2026 student accommodation applications received. The experimentation showed the ability of SAGeLogE to achieve the result. 展开更多
关键词 MIRA Method MCDM Accommodation Quota SAGeLogE
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Associations between physical activity levels and ATPase inhibitory factor 1 concentrations in older adults
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作者 Jérémy Raffin Yves Rolland +8 位作者 Annelise Genoux Guillaume Combes Mikael Croyal Bertrand Perret Sophie Guyonnet Bruno Vellas Laurent O.Martinez Philipe de Souto Barreto For the MAPT/DSA Group 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第3期409-418,共10页
Background:Adenosine triphosphatase inhibitory factor 1(IF1)is a key protein involved in energy metabolism.IF1 has been linked to various agerelated diseases,although its relationship with physical activity(PA)remains... Background:Adenosine triphosphatase inhibitory factor 1(IF1)is a key protein involved in energy metabolism.IF1 has been linked to various agerelated diseases,although its relationship with physical activity(PA)remains unclear.Additionally,the apolipoprotein A-I(apoA-I),a PA-modulated lipoprotein,could play a role in this relationship because it shares a binding site with IF1 on the cell-surface ATP synthase.We examined here the associations between chronic PA and plasma IF1 concentrations among older adults,and we investigated whether apoA-I mediated these associations.Methods:In the present work,1096 healthy adults(63.8%females)aged 70 years and over who were involved in the Multidomain Alzheimer Prevention Trial study were included.IF1 plasma concentrations(square root of ng/mL)were measured at the 1-year visit of the Multidomain Alzheimer Prevention Trial,while PA levels(square root of metabolic equivalent task min/week)were assessed using questionnaires administered each year from baseline to the 3-year visit.Multiple linear regressions were performed to investigate the associations between the first-year mean PA levels and IF1 concentrations.Mediation analyses were conducted to examine whether apoA-I mediated these associations.Mixedeffect linear regressions were carried out to investigate whether the 1-year visit IF1 concentrations predicted subsequent changes in PA.Results:Multiple linear regressions indicated that first-year mean PA levels were positively associated with IF1 concentrations(B=0.021;SE=0.010;p=0.043).Mediation analyses revealed that about 37.7%of this relationship was mediated by apoA-I(B_(ab)=0.008;SE=0.004;p=0.023).Longitudinal investigations demonstrated that higher concentrations of IF1 at the 1-year visit predicted a faster decline in PA levels over the subsequent 2 years(time×IF1:B=0.148;SE=0.066;p=0.025).Conclusion:This study demonstrates that regular PA is associated with plasma IF1 concentrations,and it suggests that apoA-I partly mediates this association.Additionally,this study finds that baseline concentrations of IF1 can predict future changes in PA.However,further research is needed to fully understand the mechanisms underlying these observations. 展开更多
关键词 Aging APOLIPOPROTEIN BIOENERGETICS Exerkine MITOCHONDRIA
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The Drought of Amazonia in 2023-2024
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作者 Jose A. Marengo Ana P. Cunha +7 位作者 Jhan-Carlo Espinoza Rong Fu Jochen Schöngart Juan C. Jimenez Mabel C. Costa Joao M. Ribeiro Sly Wongchuig Siyu Zhao 《American Journal of Climate Change》 2024年第3期567-597,共31页
The Amazon basin has experienced an extreme drought that started in the austral summer of 2022-23 and extends into 2024. This drought started earlier than other previous droughts. Although some rain fell during the au... The Amazon basin has experienced an extreme drought that started in the austral summer of 2022-23 and extends into 2024. This drought started earlier than other previous droughts. Although some rain fell during the austral summer, totals remained below average. Higher temperatures during austral winter and spring 2023, which affected most of Central South America, then aggravated drought conditions. This coincided with an intense El Niño and abnormally warm tropical North Atlantic Ocean temperatures since mid-2023. Decreased rainfall across the Amazon basin, negative anomalies in evapotranspiration (derived from latent heat) and soil moisture indicators, as well as increased temperatures during the dry-to-wet transition season, September-October-November (SON) 2023, combined to delay the onset of the wet season in the hydrological year 2023-24 by nearly two months and caused it to be uncharacteristically weak. SON 2023 registered a precipitation deficit of the order of 50 to 100 mm/month, and temperatures +3˚C higher than usual in Amazonia, leading to reduced evapotranspiration and soil moisture indicators. These processes, in turn, determined an exceptionally late onset and a lengthening of the dry season, affecting the 2023-2024 hydrological year. These changes were aggravated by a heat wave from June to December 2023. Drought-heat compound events and their consequences are the most critical natural threats to society. River levels reached record lows, or dried up completely, affecting Amazonian ecosystems. Increased risk of wildfires is another concern exacerbated by these conditions. 展开更多
关键词 El Niño SST in the Tropical Atlantic AMAZON DROUGHT River Levels HEATWAVE Dry Season Length
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Mortalin/Hspa9 involvement and therapeutic perspective in Parkinson's disease
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作者 Baptiste Texier Morgane Prime +2 位作者 Djamaa Atamena Pascale Belenguer Marion Szelechowski 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期293-298,共6页
By controlling the proper folding of proteins imported into mitochondria and ensuring crosstalk between the reticulum and mitochondria to modulate intra cellular calcium fluxes.Mortalin is a chaperone protein that pla... By controlling the proper folding of proteins imported into mitochondria and ensuring crosstalk between the reticulum and mitochondria to modulate intra cellular calcium fluxes.Mortalin is a chaperone protein that plays crucial roles in neuronal homeostasis and activity.Howeve r,its expression and stability are strongly modified in response to cellular stresses,in particular upon alte red oxidative conditions during neurodegeneration.Here,we report and discuss the abundant literature that has highlighted its contribution to the pathophysiology of Parkinson's disease,as well as its therapeutic and prognostic potential in this still incurable pathology. 展开更多
关键词 CHAPERONE Hspa9 MITOCHONDRIA Mortalin NEURODEGENERATION oxidative stress Parkinson's disease prognostic and therapeutic potential
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Experiment/simulation correlation-based methodology for metallic ballistic protection solutions
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作者 Yohan Cosquer Patrice Longère +1 位作者 Olivier Pantalé Claude Gailhac 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第11期24-38,共15页
A methodology is developed based on the coupling of a finite element code with an optimisation module for the design of land vehicle armouring composed of lightweight aluminium alloy and high strength steel plate.Foll... A methodology is developed based on the coupling of a finite element code with an optimisation module for the design of land vehicle armouring composed of lightweight aluminium alloy and high strength steel plate.Following an experiment/simulation correlation,a numerical model has been built and calibrated considering monolithic plates and then verified considering a bi-metal protection against tungsten carbide projectile mimicking the core of a 7.62×51 AP8 ammunition.In addition,a method is proposed to obtain the v_(res)-v_(i) curve for the full 7.62×51 AP8 bullet from the v_(res)-v_(i) curve obtained from the core only. 展开更多
关键词 Impact Terminal ballistics Ballistic limit MARS380 Aluminium alloy 7.62×51 AP8
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Transcriptome‑wide mapping of milk somatic cells upon subclinical mastitis infection in dairy cattle
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作者 Vittoria Bisutti Nuria Mach +7 位作者 Diana Giannuzzi Alice Vanzin Emanuele Capra Riccardo Negrini Maria Elena Gelain Alessio Cecchinato Paolo Ajmone‑Marsan Sara Pegolo 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2630-2648,共19页
Background Subclinical intramammary infection(IMI)represents a significant problem in maintaining dairy cows’health.Disease severity and extent depend on the interaction between the causative agent,environment,and ho... Background Subclinical intramammary infection(IMI)represents a significant problem in maintaining dairy cows’health.Disease severity and extent depend on the interaction between the causative agent,environment,and host.To investigate the molecular mechanisms behind the host immune response,we used RNA-Seq for the milk somatic cells(SC)transcriptome profiling in healthy cows(n=9),and cows naturally affected by subclinical IMI from Proto-theca spp.(n=11)and Streptococcus agalactiae(S.agalactiae;n=11).Data Integration Analysis for Biomarker discov-ery using Latent Components(DIABLO)was used to integrate transcriptomic data and host phenotypic traits related to milk composition,SC composition,and udder health to identify hub variables for subclinical IMI detection.Results A total of 1,682 and 2,427 differentially expressed genes(DEGs)were identified when comparing Prototheca spp.and S.agalactiae to healthy animals,respectively.Pathogen-specific pathway analyses evidenced that Proto-theca’s infection upregulated antigen processing and lymphocyte proliferation pathways while S.agalactiae induced a reduction of energy-related pathways like the tricarboxylic acid cycle,and carbohydrate and lipid metabolism.The integrative analysis of commonly shared DEGs between the two pathogens(n=681)referred to the core-mastitis response genes,and phenotypic data evidenced a strong covariation between those genes and the flow cytometry immune cells(r2=0.72),followed by the udder health(r2=0.64)and milk quality parameters(r2=0.64).Variables with r≥0.90 were used to build a network in which the top 20 hub variables were identified with the Cytoscape cyto-hubba plug-in.The genes in common between DIABLO and cytohubba(n=10)were submitted to a ROC analysis which showed they had excellent predictive performances in terms of discriminating healthy and mastitis-affected animals(sensitivity>0.89,specificity>0.81,accuracy>0.87,and precision>0.69).Among these genes,CIITA could play a key role in regulating the animals’response to subclinical IMI.Conclusions Despite some differences in the enriched pathways,the two mastitis-causing pathogens seemed to induce a shared host immune-transcriptomic response.The hub variables identified with the integrative approach might be included in screening and diagnostic tools for subclinical IMI detection. 展开更多
关键词 Data integration Immune response Milk somatic cells RNA-sequencing Subclinical mastitis
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Thermal conditioning of quail embryos has transgenerational and reversible long‑term effects
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作者 Anais Vitorino Carvalho Christelle Hennequet‑Antier +7 位作者 Romuald Rouger Joel Delaveau Thierry Bordeau Sabine Crochet Nathalie Courousse Frederique Pitel Anne Collin Vincent Coustham 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2428-2438,共11页
Background In the current context of global warming,thermal manipulation of avian embryos has received increasing attention as a strategy to promote heat tolerance in avian species by simply increasing the egg incubat... Background In the current context of global warming,thermal manipulation of avian embryos has received increasing attention as a strategy to promote heat tolerance in avian species by simply increasing the egg incubation temperature.However,because of their likely epigenetic origin,thermal manipulation effects may last more than one generation with consequences for the poultry industry.In this work,a multigenerational and transgenerational analysis of thermal manipulation during embryogenesis was performed to uncover the long-term effects of such procedure.Results Thermal manipulation repeated during 4 generations had an effect on hatchability,body weight,and weight of eggs laid in Japanese quails,with some effects increasing in importance over generations.Moreover,the effects on body weight and egg weight could be transmitted transgenerationally,suggesting non-genetic inheritance mechanisms.This hypothesis is reinforced by the observed reversion of the effect on growth after five unexposed generations.Interestingly,a beneficial effect of thermal manipulation on heat tolerance was observed a few days after hatching,but this effect was not transgenerational.Conclusions Our multigenerational study showed that thermal conditioning of quail embryos has a beneficial effect on post-hatch heat tolerance hampered by transgenerational but reversible defects on growth.Assuming that no genetic variability underlies these changes,this study provides the first demonstration of epigenetic inheritance of traits induced by environmental temperature modification associated with long-term impacts in an avian species. 展开更多
关键词 AVIAN EMBRYO Programming Temperature Transgenerational inheritance
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珠江禁渔对广东鲂资源补充群体的影响分析 被引量:15
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作者 李跃飞 李新辉 +3 位作者 杨计平 SOVAN Lek 帅方敏 李捷 《水产学报》 CAS CSCD 北大核心 2014年第4期503-509,共7页
继我国各大水系实施禁渔期制度之后,珠江水系于2011年4月1日至6月1日实现首次禁渔。广东鲂是珠江中下游地区主要的经济鱼类之一,为分析珠江实施禁渔期制度对广东鲂资源补充群体的影响,于珠江实施禁渔制度前(2006—2010年)和禁渔制度后(2... 继我国各大水系实施禁渔期制度之后,珠江水系于2011年4月1日至6月1日实现首次禁渔。广东鲂是珠江中下游地区主要的经济鱼类之一,为分析珠江实施禁渔期制度对广东鲂资源补充群体的影响,于珠江实施禁渔制度前(2006—2010年)和禁渔制度后(2011—2012年)在珠江下游肇庆江段设立固定采样点,利用定量弶网对流经该江段的广东鲂鱼苗补充群体进行调查。结果显示,禁渔前,珠江广东鲂鱼苗集中出现在4月中下旬至10月中旬,持续时间为(189±11)d,高峰期为6—8月。禁渔期制度实施之后,全年广东鲂鱼苗出现的起始时间变化不大,但是结束时间提前,持续时间略有缩短,4—5月份广东鲂鱼苗密度明显增大。广东鲂鱼苗总量及其在鱼苗补充群体中的比例均有所提高。根据禁渔前广东鲂鱼苗发生量与径流量之间存在的回归关系:LgY=0.988Lnx-4.932(R2=0.365,P<0.01),结合禁渔后实际调查结果,对禁渔的实际作用进行了估算,2011年和2012年由于禁渔分别增加了9.43×108和651.81×108尾广东鲂鱼苗。研究表明,在径流量有保障的前提下,目前的禁渔制度可以有效增加广东鲂鱼苗补充群体资源量。 展开更多
关键词 广东鲂 鱼苗 禁渔 补充群体
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西江颗粒直链藻种群生态特征 被引量:15
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作者 王超 赖子尼 +5 位作者 李跃飞 李新辉 Sovan Lek 洪颐 谭细畅 李捷 《生态学报》 CAS CSCD 北大核心 2012年第15期4793-4802,共10页
西江肇庆段是珠江干流汇入珠三角河网水域的咽喉通道,结合长期定点连续采样和空间季节性调查,重点对2009年西江干流肇庆段的颗粒直链藻(Aulacoseira granulata)的种群生态学特征进行系统分析。结果显示:全年中,颗粒直链藻在总种群中所... 西江肇庆段是珠江干流汇入珠三角河网水域的咽喉通道,结合长期定点连续采样和空间季节性调查,重点对2009年西江干流肇庆段的颗粒直链藻(Aulacoseira granulata)的种群生态学特征进行系统分析。结果显示:全年中,颗粒直链藻在总种群中所占百分比均值为25.37%,与总种群丰度存在极显著正相关关系,这表明颗粒直链藻是西江浮游植物群落的重要优势种。调查期间发现了颗粒直链藻的4种形态,包括原变种(var.granulata)、极狭变种(var.angustissima)、弯曲变种(var.curvata)和极狭变种螺旋变型(var.angustissima f.spiralis)。其中,原变种占有绝对优势地位,其相对百分组成的年均值为91.47%,推测为原变种的形态结构比其它3种形态更容易适应外界环境变化,进而形成优势群体。颗粒直链藻总密度的周年变化呈现明显的双峰型,两个峰值分别出现在8月和11月,主要得益于适宜的水温、相对稳定的水体和较高的营养盐水平,这些均有助于颗粒直链藻的生长繁殖。第一个高峰之前,颗粒直链藻总密度未出现明显的波动,这很可能是由于水体径流量增大导致的稀释作用和频繁降雨导致的水体剧烈波动对颗粒直链藻增长的负作用掩盖了水温上升所带来的益处。从空间分布来看,颗粒直链藻总丰度的最大值一般出现在S1、S5和S6站点,这与营养盐最大值的空间分布格局是一致的。 展开更多
关键词 西江 颗粒直链藻 种群生态特征
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珠三角河网水域栅藻的时空分布特征 被引量:7
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作者 王超 李新辉 +5 位作者 赖子尼 曾艳艺 高原 刘乾甫 杨婉玲 LEK Sovan 《生态学报》 CAS CSCD 北大核心 2014年第7期1800-1811,共12页
珠三角河网水域是珠江之水流入南海的必经之地,对2012年该水域浮游植物群落中的栅藻种类丰富度和生物量的时空特征及其环境影响因子进行系统阐析。调查期间共发现栅藻24种(包括变种、变型),其中具刺和无刺种类分别为11种和13种。出现率... 珠三角河网水域是珠江之水流入南海的必经之地,对2012年该水域浮游植物群落中的栅藻种类丰富度和生物量的时空特征及其环境影响因子进行系统阐析。调查期间共发现栅藻24种(包括变种、变型),其中具刺和无刺种类分别为11种和13种。出现率高且生物量贡献率大的物种仅3种,包括被甲栅藻原变种(Scenedesmus armatus var.armatus)、被甲栅藻博格变种双尾变型(S.armatus var.boglariensis f.bicaudatus)和二形栅藻(S.dimorphus),分析认为这3个物种在栅藻种群中的生态优势很可能与其形态特征存在一定的关联。栅藻种类丰富度的季节分布呈现丰水期高于枯水期的特征,空间分布呈现河网中部站位低于外侧站位的特征。此外,种类丰富度的空间分布格局存在季节差异,丰水季节呈现河网中部站位明显低于外侧站位的特征,而枯水季节西江沿线站位种类丰富度明显偏低。分析认为,水温和径流是影响栅藻种类丰富度季节变动的关键因素;同时,径流也是影响总种类丰富度空间分布格局的关键因素,而水温和营养盐是影响不同季节种类丰富度的空间格局的重要因素。栅藻种群生物量的季节分布呈现丰水期高于枯水期的特征,空间分布表现为珠江桥站位的生物量明显高于其它站位。分析认为,径流和水温是决定种群生物量季节变动的关键因素,而营养盐、水体稳定性和盐度是决定生物量空间分布格局的关键因素。栅藻生物量与种类丰富度的关系基本符合单峰模型,且偏重于单峰模型的上升区,丰富了全球多样性模式的分级特征和区域特征。 展开更多
关键词 珠江三角洲 河网 栅藻 时空特征
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植入碳纤维蜂窝夹芯结构的光纤光栅热载荷响应光谱研究 被引量:1
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作者 马驰 曾捷 +4 位作者 张景川 龚晓静 张益昕 冯翔宇 周林 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2017年第9期2927-2932,共6页
针对航天领域复合材料结构在空间服役环境的热响应监测需求,研究了一种热载荷作用下基于光纤Bragg光栅(FBG)反射光谱特征分析的碳纤维蜂窝夹芯结构监测方法。将光纤Bragg光栅传感器分别植入碳纤维蜂窝夹芯结构的不同铺层,通过监测不同... 针对航天领域复合材料结构在空间服役环境的热响应监测需求,研究了一种热载荷作用下基于光纤Bragg光栅(FBG)反射光谱特征分析的碳纤维蜂窝夹芯结构监测方法。将光纤Bragg光栅传感器分别植入碳纤维蜂窝夹芯结构的不同铺层,通过监测不同热载荷下各铺层位置的光纤光栅反射光谱,得到碳纤维蜂窝夹芯结构相关铺层位置热应变特征。研究表明,碳纤维蜂窝夹芯结构不同材料铺层的热应变特征存在一定差异。植入外蒙皮表面与玻璃布之间的光纤光栅反射光谱随着温度升高,中心波长向长波方向漂移,且波形未出现明显改变。埋植于外蒙皮第二、三层碳纤维织物预浸料之间的光栅反射光谱随着温度降低逐渐出现旁瓣、多峰等啁啾效应,其主峰与右侧次峰中心波长均向短波方向逐渐漂移,主峰峰值幅度变化较小,温度灵敏度约为5.56×10^(-3) dBm·℃^(-1),而右侧次峰幅度显著增大,温度灵敏度约为40.32×10^(-3)dBm·℃^(-1);埋植于内蒙皮和蜂窝芯子之间的光栅反射光谱随着温度降低,其半波峰带宽逐渐增大,变化率约为3.19pm·℃^(-1),且出现显著多峰趋势,这是由于层间热应力分布不均匀所形成。在-70^+60℃温度范围,各植入层热应变均随温度升高而增大,且变化趋势相接近,而在+60^+120℃温度范围内,各植入层热应变变化趋势呈现显著差异。这些特性能够为后继空间环境复合材料航天器结构状态在轨监测提供有益帮助。 展开更多
关键词 碳纤维蜂窝夹芯结构 光纤光栅 反射光谱 热应变
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一种用于故障隔离的参数区间包络线计算方法 被引量:1
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作者 李泽滔 何梦林 B.Dahhou 《现代机械》 2018年第1期31-34,共4页
基于参数区间的故障隔离方法的核心工具是区间判断阈值曲线,其计算一直是制约该方法发展的问题。参数区间动态轨迹包络线作为区间判断阈值曲线具有能够适用于多重参数故障隔离等优点,但包络线计算中的包裹效应问题在该领域内一直未能得... 基于参数区间的故障隔离方法的核心工具是区间判断阈值曲线,其计算一直是制约该方法发展的问题。参数区间动态轨迹包络线作为区间判断阈值曲线具有能够适用于多重参数故障隔离等优点,但包络线计算中的包裹效应问题在该领域内一直未能得到很好解决。介绍一种基于上、下函数的包络线计算方法,有别于区间算法计算的包络线随着迭代的进行而迅速变得肥大的可能性,采用该方法的仿真实验表明其计算的包络线的包裹效应得到很大程度上的减轻,可有效用于故障隔离的区间判断。 展开更多
关键词 故障诊断 故障隔离 参数区间 包络线 非线性系统
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近30年京津冀地区湖泊面积的变化 被引量:12
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作者 张恒 陶胜利 +1 位作者 唐志尧 方精云 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2020年第2期324-330,共7页
利用遥感、气候和社会经济统计数据,探究1987-2017年间京津冀地区湖泊面积的变化及其与自然和社会因素的关系。结果表明,该地区湖泊面积过去30年间整体上呈减少趋势,每年减少约2%,这是自然和人为因素双重影响的结果。可分为3个阶段:前10... 利用遥感、气候和社会经济统计数据,探究1987-2017年间京津冀地区湖泊面积的变化及其与自然和社会因素的关系。结果表明,该地区湖泊面积过去30年间整体上呈减少趋势,每年减少约2%,这是自然和人为因素双重影响的结果。可分为3个阶段:前10年(1987-1996年),湖泊面积增加约4.8×10~2 km^2 (约占76%),由自然因素主导(R^2=0.849,p=0.001);1997-2009年的13年间,湖泊面积呈减少趋势(减少约4.7×102km^2,占43%),主要由人为因素主导(R^2=0.536,p=0.013);最近8年(2010-2017年)中,湖泊面积呈增加趋势(增加约2.3×10~2 km^2,占36%),也主要由人为因素导致。虽然最近8年来该地区湖泊面积减少的趋势得到扭转,但地表水资源供需矛盾仍然严峻。 展开更多
关键词 京津冀地区 湖泊面积变化 归一化水体指数 相对水体面积变化率
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基于反射光谱特征辨识的光纤气压与温度集成监测方法 被引量:1
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作者 刘晓颖 曾捷 +4 位作者 郭晓华 龚晓静 李宁溪 李彤韡 王计刚 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2017年第9期2838-2843,共6页
针对飞行器机载环境多参量综合测试需求,研究了一种基于反射光谱特征辨识的光纤布拉格光栅(FBG)气压与温度集成监测方法,给出了基于膜片式结构的双参量传感机理及其理论模型。采用基于耦合模理论的OptiGrating软件,得到不同气压与温度... 针对飞行器机载环境多参量综合测试需求,研究了一种基于反射光谱特征辨识的光纤布拉格光栅(FBG)气压与温度集成监测方法,给出了基于膜片式结构的双参量传感机理及其理论模型。采用基于耦合模理论的OptiGrating软件,得到不同气压与温度条件下光纤布拉格光栅传感器仿真反射光谱。在此基础上,借助弹塑性和恢复性能优良的平膜片感压机构,构建了膜片式双光纤气压/温度集成监测模型。研究表明,恒温条件下应变传感光纤光栅反射光谱随气压增加而逐渐向短波方向偏移,其中心波长灵敏度约为0.803 0nm·MPa^(-1),且反射谱主峰及其旁瓣峰值均随气压变化呈现良好线性关系;当气压恒定而温度变化时,处于仅感温不受力状态的温度传感光纤光栅反射光谱中心波长灵敏度约为9.39pm·℃^(-1);当气压与温度交叉变化时,能够实现对变温条件下的微小气压变化实时监测。传感光纤光栅受非均匀应变效应反射光谱存在一定啁啾现象,其反射光谱旁瓣峰值波长随环境温度、气压变化均会发生偏移,具有良好线性关系,且在不同气压下反射光谱对应的同一阶数旁瓣峰值幅度相等。该研究能够为航空航天器系统多物理参量在线综合测试提供有益帮助。 展开更多
关键词 反射光谱辨识 光纤光栅 气压与温度监测 旁瓣 感压膜片
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Synergistic effect between few layer graphene and carbon nanotube supports for palladium catalyzing electrochemical oxidation of alcohols 被引量:3
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作者 Bruno F. Machado Andrea Marchionni +5 位作者 Revathi R. Bacsa Marco Bellini Julien Beausoleil Werner Oberhauser Francesco Vizza Philippe Serp 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第2期296-304,共9页
Few layer graphene (FLG), multi-walled carbon nanotubes (CNTs) and a nanotube-graphene composite (CNT-FLG) were used as supports for palladium nanoparticles. The catalysts, which were characterized by transmissi... Few layer graphene (FLG), multi-walled carbon nanotubes (CNTs) and a nanotube-graphene composite (CNT-FLG) were used as supports for palladium nanoparticles. The catalysts, which were characterized by transmission electron microscopy, Raman spectroscopy and X-ray diffraction, were used as anodes in the electrooxidation of ethanol, ethylene glycol and glycerol in half cells and in passive direct ethanol fuel cells. Upon Pd deposition, a stronger interaction was found to occur between the metal and the nanotube-graphene composite and the particle size was significantly smaller in this material (6.3 nm), comparing with nanotubes and graphene alone (8 and 8.4 nm, respectively). Cyclic voltammetry experiments conducted with Pd/CNT, Pd/FLG and Pd/CNT-FLG in 10 wt% ethanol and 2 M KOH solution, showed high specific currents of 1.48, 2.29 and 2.51 mA-/zgp-d, respectively. Moreover, the results obtained for ethylene glycol and glycerol oxidation highlighted the excellent electrocatalytic activity of Pd/CNT-FLG in terms of peak current density (up to 3.70 mAgd for ethylene glycol and 1.84 mAfor glycerol, respectively). Accordingly, Pd/CNT-FLG can be considered as the best performing one among the electrocatalysts ever reported for ethylene glycol oxidation, especially considering the low metal loading used in this work. Direct ethanol fuel cells at room temperature were studied by obtaining power density curves and undertaking galvanostatic experiments. The power density outputs using Pd/CNT, Pd/FLG and Pd/CNT-FLG were 12.1, 16.3 and 18.4 mW.cm-2, respectively. A remarkable activity for ethanol electrooxidation was shown by Pd/CNT-FLG anode catalyst. In a constant current experiment, the direct ethanol fuel cell containing Pd/CNT-FLG could continuously deliver 20 mA.cm-2 for 9.5 h during the conversion of ethanol into acetate of 30%, and the energy released from the cell was about 574 J. 展开更多
关键词 ELECTROOXIDATION ALCOHOLS fuel cells PALLADIUM GRAPHENE nanotube-graphene composites
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Liquid−liquid structure transition in metallic melt and its impact on solidification:A review 被引量:2
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作者 Yi-xuan HE Jin-shan LI +1 位作者 Jun WANG Eric BEAUGNON 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第9期2293-2310,共18页
Understanding the nature of liquid structures and properties has always been a hot field in condensed matter physics and metallic materials science.The liquid is not homogeneous and the local structures inside change ... Understanding the nature of liquid structures and properties has always been a hot field in condensed matter physics and metallic materials science.The liquid is not homogeneous and the local structures inside change discontinuously with temperature,pressure,etc.The liquid will experience liquid−liquid structure transition under a certain condition.Liquid−liquid structure transition widely exists in many metals and alloys and plays an important role in the final microstructure and the properties of the solid alloys.This work provides a comprehensive review on this unique structure transition in the metallic liquid together with the recent progress of its impact on the following microstructure and properties after solidification.These effects are discussed by integrating them into different experimental results and theoretical considerations.The application of liquid−liquid structure transition as a strategy to tailor the properties of metals and alloys is proven to be practical and efficient. 展开更多
关键词 liquid−liquid structure transition metals and alloys thermal history SOLIDIFICATION
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Ecto-F_1-ATPase: A moonlighting protein complex and an unexpected apoA-I receptor 被引量:1
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作者 Pierre Vantourout Claudia Radojkovic +3 位作者 Laeticia Lichtenstein Véronique Pons Eric Champagne Laurent O Martinez 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第47期5925-5935,共11页
Mitochondrial ATP synthase has been recently detected at the surface of different cell types, where it is a high affinity receptor for apoA-I, the major protein component in high density lipoproteins (HDL). Cell surfa... Mitochondrial ATP synthase has been recently detected at the surface of different cell types, where it is a high affinity receptor for apoA-I, the major protein component in high density lipoproteins (HDL). Cell surface ATP synthase (namely ecto-F1-ATPase) expression is related to different biological effects, such as regulation of HDL uptake by hepatocytes, endothelial cell proliferation or antitumor activity of Vγ9/Vδ2 T lymphocytes. This paper reviews the recently discovered functions and regulations of ecto-F1-ATPase. Particularly, the role of the F1-ATPase pathway(s) in HDL-cholesterol uptake and apoA-Imediated endothelial protection suggests its potential importance in reverse cholesterol transport and its regulation might represent a potential therapeutic target for HDL-related therapy for cardiovascular diseases. Therefore, it is timely for us to better understand how this ecto-enzyme and downstream pathways are regulated and to develop pharmacologic interventions. 展开更多
关键词 F1Fo ATP synthase High density lipoproteins receptor Apolipoprotein A-I Purinergic receptor P2Y13 Adenylate kinase NUCLEOTIDE ENDOTHELIUM Antitumor immunity
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关于实验心理学中推理的现代心理测量方法(英文) 被引量:1
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作者 Jean-Frangois Bonnefon Stephane Vautier 《心理学报》 CSSCI CSCD 北大核心 2010年第1期99-110,共12页
推理测验与推理实验不同。推理测验用来衡量智商;而推理实验则用来研究推理的心理过程。测验旨在找出能力的个体差异;而实验则意在突出所有个体的一般性心理过程。近年来,心理学中的推理已经发生了变化,我们在理论进化方面简要地总结了... 推理测验与推理实验不同。推理测验用来衡量智商;而推理实验则用来研究推理的心理过程。测验旨在找出能力的个体差异;而实验则意在突出所有个体的一般性心理过程。近年来,心理学中的推理已经发生了变化,我们在理论进化方面简要地总结了如下这些变化:关注点从推理任务中的反应过程变为个体对不同任务做反应时的差异和其中稳定的反应模式,开始考虑不同推理者的组织差异和数量差异(犹如不同游泳运动员的游泳动作和肌肉数量)。然而,这些理论创新必须有精确的建模技术的支持。我们将以条件推理材料为例,展示了现代心理测量方法可以帮我们解决理论创新中产生的三类主要的研究问题。 展开更多
关键词 推理 实验 个体差异 心理测量 条件
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Electro-Hydrodynamics and Kinetic Modeling of Dry and Humid Air Flows Activated by Corona Discharges 被引量:1
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作者 J. P. SARRETTE O. EICHWALD +2 位作者 F. MARCHAL O. DUCASSE M. YOUSFI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第5期469-472,共4页
The present work is devoted to the 2D simulation of a point-to-plane Atmospheric Corona Discharge Reactor (ACDR) powered by a DC high voltage supply. The corona reactor is periodically crossed by thin mono filamenta... The present work is devoted to the 2D simulation of a point-to-plane Atmospheric Corona Discharge Reactor (ACDR) powered by a DC high voltage supply. The corona reactor is periodically crossed by thin mono filamentary streamers with a natural repetition frequency of some tens of kHz. The study compares the results obtained in dry air and in air mixed with a small amount of water vapour (humid air). The simulation involves the electro-dynamics~ chemical kinetics and neutral gas hydrodynamics phenomena that influence the kinetics of the chemical species transformation. Each discharge lasts about one hundred of a nanosecond while the post- discharge occurring between two successive discharges lasts one hundred of a microsecond. The ACDR is crossed by a lateral dry or humid air flow initially polluted with 400 ppm of NO. After 5 ms, the time corresponding to the occurrence of 50 successive discharge/post-discharge phases, a higher NO removal rate and a lower ozone production rate are found in humid air. This change is due to the presence of the HO2 species formed from the H primary radical in the discharge zone. 展开更多
关键词 DC corona discharge humid air chemistry plasma simulation NO treatment
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Small-world networks of neuroblastoma cells cultured in three-dimensional polymeric scaffolds featuring multi-scale roughness 被引量:1
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作者 Valentina Onesto Angelo Accardo +1 位作者 Christophe Vieu Francesco Gentile 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第4期759-768,共10页
Understanding the mechanisms underlying cell-surface interaction is of fundamental importance for the rational design of scaffolds aiming at tissue engineering,tissue repair and neural regeneration applications.Here,w... Understanding the mechanisms underlying cell-surface interaction is of fundamental importance for the rational design of scaffolds aiming at tissue engineering,tissue repair and neural regeneration applications.Here,we examined patterns of neuroblastoma cells cultured in three-dimensional polymeric scaffolds obtained by two-photon lithography.Because of the intrinsic resolution of the technique,the micrometric cylinders composing the scaffold have a lateral step size of^200 nm,a surface roughness of around 20 nm,and large values of fractal dimension approaching 2.7.We found that cells in the scaffold assemble into separate groups with many elements per group.After cell wiring,we found that resulting networks exhibit high clustering,small path lengths,and small-world characteristics.These values of the topological characteristics of the network can potentially enhance the quality,quantity and density of information transported in the network compared to equivalent random graphs of the same size.This is one of the first direct observations of cells developing into 3D small-world networks in an artificial matrix. 展开更多
关键词 3D NETWORKS BIOMATERIALS nano-topography network topology neuro-regeneration SMALL-WORLD NETWORKS tissue engineering TWO-PHOTON lithography
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