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Hybrid Professionals and Academic Productivity: The Case of the University Polyclinic in Messina (Sicily) 认领
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作者 Angela Alibrandi Lara Gitto +1 位作者 Michele Limosani Guido Noto 《健康(英文)》 2021年第1期1-15,共15页
The productivity of medical staff within a polyclinic is not an easy task due to the multiple activities that physicians must perform at the same time: not only healthcare for patients, but also academic activities, s... The productivity of medical staff within a polyclinic is not an easy task due to the multiple activities that physicians must perform at the same time: not only healthcare for patients, but also academic activities, such as scientific research and teaching. Hybrid professionals are healthcare professionals who have to play multiple roles, often not precisely identified. This analysis examines the case study of the University Polyclinic of Messina (Italy) where three university departments and 7 Dipartimenti di Attività Integrate (DAI) are distinguished and physicians (both professors and researchers) are called to reconcile multiple tasks. Given the distinction between university departments and DAIs, the aim of this contribution is to identify the organizational elements that prove to be predictors of scientific efficiency and productivity. To what extent does the inclusion in a DAI or within a university department affect individual incentives? A new dataset is built for the present research containing information on University Polyclinic of Messina physicians (full professors, associate professors, researchers). From the Scopus online database (<a href="https://www.scopus.com/home.uri">https://www.scopus.com/home.uri</a>) individual information relating to the number of publications, the number of citations, h-index was obtained. The latter is used to assess the quality of individual research;in order to evaluate the teaching activity, the number of hours dedicated to didactical activities is taken into account, together with the number of teaching hours required by one’s role. Information related to remuneration and the circumstance of carrying out intramural activities has also been included. A thorough statistical analysis is carried out and the individual groups (DAI and university departments) are compared through the Kruskal Wallis test. Estimating a Poisson Gamma mixture model highlights those variables that are significant predictors of scientific productivity. Attention paid to organizational metho 展开更多
关键词 Hybrid Professionals University Departments DAI H-INDEX Poisson-Gamma Mixture Model
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Optimization of Wear Factors of Aluminium Hybrid Metal Matrix Composites Using Taguchi Method 认领
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作者 P. B. Asha Sneha Sarika Murthy +3 位作者 C. R. Prakash Rao V. Ravi Kumar R. Kiran C. N. Suresha 《矿物质和材料特性和工程(英文)》 2021年第1期38-47,共10页
Hybrid metal matrix composites (Hmmc) are found to be more superior than the conventional composite materials because of their improved mechanical properties, which can be suited for an extensive range of engineering ... Hybrid metal matrix composites (Hmmc) are found to be more superior than the conventional composite materials because of their improved mechanical properties, which can be suited for an extensive range of engineering applications. Automobile and aerospace industries widely make use of hybrid composites as they possess excellent corrosion, wear resistance, low density, and high strength. This paper displays the strategy to build the hybrid composite utilizing Stir casting Method. Present investigation includes the creation of composites utilizing boron carbide (2%, 4%, 6% volume) and Red mud (2% volume) as the reinforcements and Structural aluminium as the matrix. Experimental investigation of wear analysis of the composites was carried out according to the L9 Taguchi method. The designated number of experiments was accomplished to probe the impact of control factors on the specific wear rate (SWR) of the developed composites. ANOVA was carried out and Wt%. Reinforcement was found to be the decisive factor on the SWR of the developed hybrid composite. The Confirmatory test was successfully carried out and the computed error was found to be varying from 0.878% to 2.58%. 展开更多
关键词 Taguchi ANNOVA WEAR Signal-to-Noise Ratio Hybrid Metal Matrix Composite
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Feasibility Limits for a Hybrid System with Ocean Wave and Ocean Current Power Plants in Southern Coast of Brazil 认领
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作者 Andrea Fischer Jones S. Silva Alexandre Beluco 《水能与环境工程(英文)》 2021年第1期1-17,共17页
Some types of renewable energy have been experiencing rapid evolution in recent decades, notably among the energies associated with the oceans, such as wave and current energies. The development of new energy conversi... Some types of renewable energy have been experiencing rapid evolution in recent decades, notably among the energies associated with the oceans, such as wave and current energies. The development of new energy conversion technologies for these two forms of energy has been offering a large number of equipment configurations and plant geometries for energy conversion. This process can be implemented aiming at the result of feasibility studies in places with energy potentials, establishing minimum feasibility limits to be reached. This work aims to contribute in this sense with a feasibility study of a system with ocean wave power plants and with socio-current power plants to be operated on the southern coast of Brazil. This study evaluates a hybrid system with contributions from energy supplies obtained from wave plants and current plants, connected to the grid and supplying the demand of the municipalities in the North Coast region of the State of Rio Grande do Sul, the southernmost state of Brazil. The study was carried out with simulations with the Homer Legacy software, with some adaptations for the simulation of ocean wave plants and ocean current plants. The results indicate that the ocean wave power plants were viable in the vast majority of simulated scenarios, while the ocean current power plants were viable in the scenarios with more intense average ocean current speeds and with more expensive energy acquired from the interconnected system. 展开更多
关键词 Hybrid Energy Systems Ocean Wave Power Plants Ocean Current Power Plants Feasibility Limits New Technologies Software Homer
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Model updating of a bridge structure using vibration test data based on GMPSO and BPNN:case study 认领
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作者 Xia Zhiyuan Li Aiqun +1 位作者 Shi Huiyuan Li Jianhui 《地震工程与工程振动:英文版》 SCIE EI 2021年第1期213-221,共9页
Model updating issues with high-dimensional and strong-nonlinear optimization processes are still unsolved by most optimization methods.In this study,a hybrid methodology that combines the Gaussian-white-noise-mutatio... Model updating issues with high-dimensional and strong-nonlinear optimization processes are still unsolved by most optimization methods.In this study,a hybrid methodology that combines the Gaussian-white-noise-mutation particle swarm optimization(GMPSO),back-propagation neural network(BPNN)and Latin hypercube sampling(LHS)technique is proposed.In this approach,as a meta-heuristic algorithm with the least modification to the standard PSO,GMPSO simultaneously offers convenient programming and good performance in optimization.The BPNN with LHS establishes the meta-models for FEM to accelerate efficiency during the updating process.A case study of the model updating of an actual bridge with no distribution but bounded parameters was carried out using this methodology with two different objective functions.One considers only the frequencies of the main girder and the other considers both the frequencies and vertical displacements of typical points.The updating results show that the methodology is a sound approach to solve an actual complex bridge structure and offers good agreement in the frequencies and mode shapes of the updated model and test data.Based on the shape comparison of the main girder at the finished state with different objective functions,it is emphasized that both the dynamic and static responses should be taken into consideration during the model updating process. 展开更多
关键词 model updating hybrid methodology advanced particle swarm optimization neural network case study
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Profiles and Source Apportionment of Nonmethane Volatile Organic Compounds in Winter and Summer in Xi’an, China, based on the Hybrid Environmental Receptor Model 认领
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作者 Jian SUN Zhenxing SHEN +8 位作者 Yue ZHANG Wenting DAI Kun HE Hongmei XU Zhou ZHANG Long CUI Xuxiang LI Yu HUANG Junji CAO 《大气科学进展:英文版》 SCIE CAS 2021年第1期116-131,共16页
Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment mon... Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment monitoring stations for NMHCs and 20 OVOC species were analyzed.Significant seasonal differences were noted for total VOC(TVOC,NMHCs and OVOCs)concentrations and compositions.The campaign-average TVOC concentrations in winter(85.3±60.6 ppbv)were almost twice those in summer(47.2±31.6 ppbv).Alkanes and OVOCs were the most abundant category in winter and summer,respectively.NMHCs,but not OVOCs,had significantly higher levels on weekends than on weekdays.Total ozone formation potential was higher in summer than in winter(by 50%)because of the high concentrations of alkenes(particularly isoprene),high temperature,and high solar radiation levels in summer.The Hybrid Environmental Receptor Model(HERM)was used to conduct source apportionment for atmospheric TVOCs in winter and summer,with excellent accuracy.HERM demonstrated its suitability in a situation where only partial source profile data were available.The HERM results indicated significantly different seasonal source contributions to TVOCs in Xi’an.In particular,coal and biomass burning had contributions greater than half in winter(53.4%),whereas traffic sources were prevalent in summer(53.1%).This study’s results highlight the need for targeted and adjustable VOC control measures that account for seasonal differences in Xi’an;such measures should target not only the severe problem with VOC pollution but also the problem of consequent secondary pollution(e.g.,from ozone and secondary organic aerosols). 展开更多
关键词 NMHCS OVOCs source apportionment Hybrid Environmental Receptor Model
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中晚熟粒用高粱不同组合杂交种的筛选 认领
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作者 姚燕辉 赵兴奎 +1 位作者 彭锁堂 段永红 《农学学报》 2021年第1期1-6,共6页
为选育优质中晚熟粒用高粱新材料,本试验采用单因素随机区组设计,以4份不同杂交组合高粱亲本为试验材料,分析不同组合杂交种的生育期、农艺性状及产量性状的差异,筛选最佳的中晚熟粒用高粱组合。高粱组合杂交种的生育期存在差异,但相差... 为选育优质中晚熟粒用高粱新材料,本试验采用单因素随机区组设计,以4份不同杂交组合高粱亲本为试验材料,分析不同组合杂交种的生育期、农艺性状及产量性状的差异,筛选最佳的中晚熟粒用高粱组合。高粱组合杂交种的生育期存在差异,但相差不大,生育期最长的高粱组合23A×014-52,生育期为134天,生育期最短的高粱组合147A×014-34,生育期为123天;高粱组合23A×014-52的农艺性状较好;与对照相比,增产的高粱组合为23A×014-52、27A×017-95,其中高粱组合23A×014-52增产明显,较对照高出30.06%。结合分析农艺性状、产量性状等,高粱组合23A×014-52杂种优势较突出,可以作为培育中晚熟粒用高粱的亲本材料。 展开更多
关键词 粒用高粱 杂交种 筛选 农艺性状 产量性状
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玉米品种硕达709选育研究 认领
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作者 高守山 《农业科技与装备》 2021年第1期1-3,共3页
以玉米自交系zh81为母本,以玉米自交系sn101为父本,采用常规育种技术手段和系谱选育法,组配而成中晚熟玉米杂交种硕达709。通过品种试验,考察硕达709品种及亲本特征特性,介绍其栽培与制种技术要点,以期为杂交种硕达709的推广应用提供参考。
关键词 玉米 杂交种 选育 硕达709
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基于信息化技术的以学生为中心的混合式教学模式研究——以“轨道交通信号基础设备”课程为例 认领
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作者 赵明国 《无线互联科技》 2021年第1期118-120,共3页
随着云时代的到来,信息技术极大地改变了学校的教学方式,传统课堂的教学模式也受到前所未有的挑战。在这种情况下,基于信息化技术的教学模式的出现为传统课堂教学的改革提供了机遇和挑战。因此,基于信息化技术的专业核心课建设的创新与... 随着云时代的到来,信息技术极大地改变了学校的教学方式,传统课堂的教学模式也受到前所未有的挑战。在这种情况下,基于信息化技术的教学模式的出现为传统课堂教学的改革提供了机遇和挑战。因此,基于信息化技术的专业核心课建设的创新与实践具有重大的现实意义和价值。 展开更多
关键词 专业核心课 信息化技术 混合式 教学资源
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混合动力车型动力电池一种先进的热管理设计理念 认领
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作者 李明敏 程树黄炯 《时代汽车》 2021年第1期16-17,共2页
随着国家排放节能减排要求愈发严格,汽车发展日趋电动化,越来越多的传统汽车厂家都选择在当前传统车平台上开发混合动力汽车作为纯电动汽车的过渡车型。混合动力汽车的电池为动力电池,由于电池容量小放电倍率高,如不进行主动冷却导致电... 随着国家排放节能减排要求愈发严格,汽车发展日趋电动化,越来越多的传统汽车厂家都选择在当前传统车平台上开发混合动力汽车作为纯电动汽车的过渡车型。混合动力汽车的电池为动力电池,由于电池容量小放电倍率高,如不进行主动冷却导致电池的温度急剧攀升。本文主要介绍一种比较先进的电池包双冷却液冷系统设计理念,通过对比当前市场常见风冷系统,从能耗、工况等角度通过对比手法来阐述该设计理念的优越性和先进性。 展开更多
关键词 混动 动力电池 双冷却系统 能耗 冷却效率
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Modeling and forecasting of COVID-19 using a hybrid dynamic model based on SEIRD with ARIMA corrections 认领
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作者 Maher Ala’raj Munir Majdalawieh Nishara Nizamuddin 《传染病建模》 2021年第1期98-111,共14页
The outbreak of novel coronavirus(COVID-19)attracted worldwide attention.It has posed a significant challenge for the global economies,especially the healthcare sector.Even with a robust healthcare system,countries we... The outbreak of novel coronavirus(COVID-19)attracted worldwide attention.It has posed a significant challenge for the global economies,especially the healthcare sector.Even with a robust healthcare system,countries were not prepared for the ramifications of COVID-19.Several statistical,dynamic,and mathematical models of the COVID-19 outbreak including the SEIR model have been developed to analyze the infection its transmission dynamics.The objective of this research is to use public data to study the properties associated with the COVID-19 pandemic to develop a dynamic hybrid model based on SEIRD and ascertainment rate with automatically selected parameters.The proposed model consists of two parts:the modified SEIRD dynamic model and ARIMA models.We fit SEIRD model parameters against historical values of infected,recovered and deceased population divided by ascertainment rate,which,in turn,is also a parameter of the model.Residuals of the first model for infected,recovered,and deceased populations are then corrected using ARIMA models.The model can analyze the input data in real-time and provide long-and short-term forecasts with confidence intervals.The model was tested and validated on the US COVID statistics dataset from the COVID Tracking Project.For validation,we use unseen recent statistical data.We use five common measures to estimate model prediction ability:MAE,MSE,MLSE,Normalized MAE,and Normalized MSE.We proved a great model ability to make accurate predictions of infected,recovered,and deceased patients.The output of the model can be used by the government,private sectors,and policymakers to reduce health and economic risks significantly improved consumer credit scoring. 展开更多
关键词 COVID 19 CORONAVIRUS SEIRD model ARIMA Hybrid model
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基于云班课的高职食品添加剂混合式教学法 认领
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作者 韩露 陈正冬 徐海菊 《现代农业研究》 2021年第1期39-40,共2页
本论文以蓝墨云班课为平台,研究高职食品添加剂课程的混合式教学法。重点阐述了该方法的课前、课中、课后具体实施过程,并分析了通过云班课实现食品添加剂混合式教学法的优点,以及基于高职食品添加剂课程实际情况需要改进的方向。
关键词 食品添加剂 教学 混合式
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High‑Energy and High‑Power Pseudocapacitor–Battery Hybrid Sodium‑Ion Capacitor with Na+ Intercalation Pseudocapacitance Anode 认领
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作者 Qiulong Wei Qidong Li +5 位作者 Yalong Jiang Yunlong Zhao Shuangshuang Tan Jun Dong Liqiang Mai Dong‑Liang Peng 《纳微快报:英文版》 SCIE EI CAS 2021年第3期209-221,共13页
High-performance and low-cost sodium-ion capacitors(SICs)show tremendous potential applications in public transport and grid energy storage.However,conventional SICs are limited by the low specific capacity,poor rate ... High-performance and low-cost sodium-ion capacitors(SICs)show tremendous potential applications in public transport and grid energy storage.However,conventional SICs are limited by the low specific capacity,poor rate capability,and low initial coulombic efficiency(ICE)of anode materials.Herein,we report layered iron vanadate(Fe5V15O39(OH)9·9H2O)ultrathin nanosheets with a thickness of~2.2 nm(FeVO UNSs)as a novel anode for rapid and reversible sodium-ion storage.According to in situ synchrotron X-ray diffractions and electrochemical analysis,the storage mechanism of FeVO UNSs anode is Na+intercalation pseudocapacitance under a safe potential window.The FeVO UNSs anode delivers high ICE(93.86%),high reversible capacity(292 mAh g^−1),excellent cycling stability,and remarkable rate capability.Furthermore,a pseudocapacitor–battery hybrid SIC(PBH-SIC)consisting of pseudocapacitor-type FeVO UNSs anode and battery-type Na3(VO)2(PO4)2F cathode is assembled with the elimination of presodiation treatments.The PBH-SIC involves faradaic reaction on both cathode and anode materials,delivering a high energy density of 126 Wh kg^−1 at 91 W kg^−1,a high power density of 7.6 kW kg^−1 with an energy density of 43 Wh kg−1,and 9000 stable cycles.The tunable vanadate materials with high-performance Na+intercalation pseudocapacitance provide a direction for developing next-generation highenergy capacitors. 展开更多
关键词 Sodium-ion capacitors PSEUDOCAPACITANCE Hybrid capacitors Two-dimensional materials Iron vanadate
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基于简化基因组测序的越橘杂交后代鉴定 认领
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作者 刘有春 刘威生 +8 位作者 王兴东 孙斌 刘修丽 杨艳敏 魏鑫 杨玉春 张舵 刘成 李天忠 《中国农业科学》 CAS 北大核心 2021年第2期370-378,共9页
【目的】针对遗传群体测序数据开发一种杂交后代鉴定方法,以获得继承双亲基因的真杂种后代,为果树杂交育种、遗传分析及遗传图谱构建奠定基础。【方法】本研究以越橘正反交群体共计318个F1子代和2个亲本为试材,利用SLAF技术进行简化基... 【目的】针对遗传群体测序数据开发一种杂交后代鉴定方法,以获得继承双亲基因的真杂种后代,为果树杂交育种、遗传分析及遗传图谱构建奠定基础。【方法】本研究以越橘正反交群体共计318个F1子代和2个亲本为试材,利用SLAF技术进行简化基因组测序并比对越橘参考基因组获得群体SNP数据,通过稀有等位变异分析和基于PCA、K-means聚类的遗传关系分析鉴定供试群体中的非杂交后代,结果利用双亲纯合显性SNP标记进行验证。【结果】SLAF简化测序共获得65.89 Gb数据,GC含量39.72%,平均Q30为95.04%,亲本和子代平均测序深度为12.86×和5.41×。参照四倍体越橘基因组信息,正、反交组合分别获得73543个和114851个SNP,利用次等位基因频率(MAF)>0.05的SNP数据集分别对正、反交群体进行PCA和K-means聚类分析,鉴定出4个离群个体;利用MAF<0.05的SNP数据集对正、反交群体进行个体稀有等位变异和个体特有的稀有等位变异数统计,共鉴定出10个离群个体(包含了MAF>0.05的SNP数据集鉴定的4个离群个体)。通过双亲纯合显性SNP标记进行验证,正、反交群体双亲纯合SNP位点分别占群体总SNP的34.56%和38.95%,除H194-123个体外,其余非杂交后代在验证结果中同为离群个体,即准确通过验证。【结论】对于有参考基因组物种的杂交群体,利用基于测序的SNP次等位基因频率(MAF)数据集,采用遗传关系和个体特有的稀有等位变异分析方法,从不同角度反映群体子代间的遗传关系以鉴别离群个体,是一种鉴定群体假杂交后代的有效方法。 展开更多
关键词 越橘 正反交群体 SLAF测序 SNP 稀有等位变异数 杂交后代
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有机小分子杂化聚降冰片烯形状记忆性能的研究 认领
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作者 逄见光 杨晓东 +1 位作者 薛海恩 李洪春 《橡胶工业》 CAS 2021年第1期3-9,共7页
以聚降冰片烯(PNB)为研究对象,研究增塑剂(塑分T和环保芳烃油)和有机小分子(微晶蜡、淀粉和碱木质素)对PNB形状记忆性能的影响。结果表明:添加环保芳烃油的PNB玻璃化温度在室温(20℃)附近,塑分T对PNB的玻璃化温度影响不大,有利于PNB在... 以聚降冰片烯(PNB)为研究对象,研究增塑剂(塑分T和环保芳烃油)和有机小分子(微晶蜡、淀粉和碱木质素)对PNB形状记忆性能的影响。结果表明:添加环保芳烃油的PNB玻璃化温度在室温(20℃)附近,塑分T对PNB的玻璃化温度影响不大,有利于PNB在室温下的形变固定;在玻璃化温度起始温度下拉伸时,几种填充PNB均出现屈服现象,且呈现硬而韧的应力-应变特征;几种填充PNB均具有优良的传统形状记忆性能,形状固定率在98%以上,形状恢复率在70%以上,其可逆塑性形状记忆性能低于传统形状记忆性能,可逆塑性形状固定率为49%~77%;微晶蜡杂化PNB具有优异的形状记忆性能。 展开更多
关键词 聚降冰片烯 增塑剂 有机小分子 杂化 形状记忆性能
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Printable Zinc‑Ion Hybrid Micro‑Capacitors for Flexible Self‑Powered Integrated Units 认领
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作者 Juan Zeng Liubing Dong +4 位作者 Lulu Sun Wen Wang Yinhua Zhou Lu Wei Xin Guo 《纳微快报:英文版》 SCIE EI CAS 2021年第1期367-380,共14页
Wearable self-powered systems integrated with energy conversion and storage devices such as solar-charging power units arouse widespread concerns in scientific and industrial realms.However,their applications are hamp... Wearable self-powered systems integrated with energy conversion and storage devices such as solar-charging power units arouse widespread concerns in scientific and industrial realms.However,their applications are hampered by the restrictions of unbefitting size matching between integrated modules,limited tolerance to the variation of input current,reliability,and safety issues.Herein,flexible solar-charging self-powered units based on printed Zn-ion hybrid micro-capacitor as the energy storage module is developed.Unique 3D micro-/nano-architecture of the biomass kelp-carbon combined with multivalent ion(Zn2+)storage endows the aqueous Zn-ion hybrid capacitor with high specific capacity(196.7 mAh g^−1 at 0.1 A g^−1).By employing an in-plane asymmetric printing technique,the fabricated quasi-solid-state Zn-ion hybrid microcapacitors exhibit high rate,long life and energy density up to 8.2μWh cm^−2.After integrating the micro-capacitor with organic solar cells,the derived self-powered system presents outstanding energy conversion/storage efficiency(ηoverall=17.8%),solar-charging cyclic stability(95%after 100 cycles),wide current tolerance,and good mechanical flexibility.Such portable,wearable,and green integrated units offer new insights into design of advanced self-powered systems toward the goal of developing highly safe,economic,stable,and long-life smart wearable electronics. 展开更多
关键词 Zinc-ion hybrid capacitor Kelp-carbon Zinc metal anode Multivalent ion storage Self-powered unit
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某集装箱船混合式脱硫改造方案 认领
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作者 钟元吉 薛大亮 +2 位作者 李达 李中华 王震 《中国修船》 2021年第1期12-14,共3页
为满足硫化物的排放要求,近年来越来越多的旧船实施了脱硫改造工作,文章以某集装箱的混合式脱硫改造项目为例,分析了几种可行的脱硫改造布置方案,通过对比其优缺点,确定了最合理的改造方案。
关键词 脱硫改造 混合式 硫化物 排放
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Hybrid Recommender System for Tourism Based on Big Data and AI:A Conceptual Framework 认领
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作者 Khalid AL Fararni Fouad Nafis +3 位作者 Badraddine Aghoutane Ali Yahyaouy Jamal Riffi Abdelouahed Sabri 《大数据挖掘与分析(英文)》 EI 2021年第1期47-55,共9页
With the development of the Internet,technology,and means of communication,the production of tourist data has multiplied at all levels(hotels,restaurants,transport,heritage,tourist events,activities,etc.),especially w... With the development of the Internet,technology,and means of communication,the production of tourist data has multiplied at all levels(hotels,restaurants,transport,heritage,tourist events,activities,etc.),especially with the development of Online Travel Agency(OTA).However,the list of possibilities offered to tourists by these Web search engines(or even specialized tourist sites)can be overwhelming and relevant results are usually drowned in informational"noise",which prevents,or at least slows down the selection process.To assist tourists in trip planning and help them to find the information they are looking for,many recommender systems have been developed.In this article,we present an overview of the various recommendation approaches used in the field of tourism.From this study,an architecture and a conceptual framework for tourism recommender system are proposed,based on a hybrid recommendation approach.The proposed system goes beyond the recommendation of a list of tourist attractions,tailored to tourist preferences.It can be seen as a trip planner that designs a detailed program,including heterogeneous tourism resources,for a specific visit duration.The ultimate goal is to develop a recommender system based on big data technologies,artificial intelligence,and operational research to promote tourism in Morocco,specifically in the Daraa-Tafilalet region. 展开更多
关键词 recommender systems user profiling content-based filtering collaborative filtering hybrid recommender system e-tourism trip planning
棕点石斑鱼(♀)与蓝身大斑石斑鱼(♂)杂交子代核型分析 认领
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作者 吴玉萍 田永胜 +7 位作者 李振通 张晶晶 黎琳琳 王林娜 李子奇 陈帅 牛艺彭 翟介明 《广东海洋大学学报》 CAS 2021年第1期119-123,共5页
【目的】研究棕点石斑鱼(Epinephelus tukula,♀)与蓝身大斑石斑鱼(Epinephelus fuscoguttatus,♂)杂交F1代(下称"金虎斑")的染色体核型。【方法】采用头肾-PHA注射法制备金虎斑染色体,并分析其核型。【结果与结论】金虎斑二... 【目的】研究棕点石斑鱼(Epinephelus tukula,♀)与蓝身大斑石斑鱼(Epinephelus fuscoguttatus,♂)杂交F1代(下称"金虎斑")的染色体核型。【方法】采用头肾-PHA注射法制备金虎斑染色体,并分析其核型。【结果与结论】金虎斑二倍体染色体数为48,包括23对端部着丝粒染色体,1对亚中部着丝粒染色体,核型公式是2n=48=2sm+46t,染色体臂数(NF)为50。与其他石斑鱼核型相比,金虎斑染色体核型特点符合典型的高位类群鱼类核型特征;根据染色体臂数,金虎斑属于特化类群。 展开更多
关键词 棕点石斑鱼 蓝身大斑石斑鱼 杂交子代 核型 染色体
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Derivation of the multi-model generalized labeled multi-Bernoulli filter:a solution to multi-target hybrid systems 认领
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作者 Weihua WU Yichao CAI +3 位作者 Hongbin JIN Mao ZHENG Xun FENG Zewen GUAN 《信息与电子工程前沿:英文版》 SCIE EI 2021年第1期79-87,共9页
In this study,we extend traditional(single-target)hybrid systems to multi-target hybrid systems with a focus on the multi-maneuvering-target tracking system.This system consists of a continuous state,a discrete and sw... In this study,we extend traditional(single-target)hybrid systems to multi-target hybrid systems with a focus on the multi-maneuvering-target tracking system.This system consists of a continuous state,a discrete and switchable state,and a discrete,time-constant,and unique state.By defining a new generalized labeled multi-Bernoulli density,we prove that it is closed under the Chapman-Kolmogorov prediction and Bayes update for multi-target hybrid systems.In other words,we provide the exact derivation of a solution to this system,i.e.,the multi-model generalized labeled multi-Bemoulli filter,which has been developed without strict proof. 展开更多
关键词 Multi-maneuvering-target tracking MULTI-MODEL Generalized labeled multi・Bemoulli filter Multi-target hybrid systems
Thiophene-Conjugated Porous C3N4 Nanosheets for Boosted Photocatalytic Nicotinamide Cofactor Regeneration to Facilitate Solar-to-Chemical Enzymatic Reactions 认领
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作者 Yao Tian Yongchao Zong +5 位作者 Yinuo Zhou Jiansheng Li Nan Yang Mai Zhang Zhiqi Guo Hao Song 《天津大学学报:英文版》 EI CAS 2021年第1期42-54,共13页
The low catalytic efficiency of redox-active cofactor photoregeneration severely limits the performance of photoenzymatic hybrid systems. Herein, we synthesized thiophene-conjugated porous C3N4 nanosheets(CN-ATCN) exh... The low catalytic efficiency of redox-active cofactor photoregeneration severely limits the performance of photoenzymatic hybrid systems. Herein, we synthesized thiophene-conjugated porous C3N4 nanosheets(CN-ATCN) exhibiting boosted photoregeneration activity of nicotinamide cofactors(NADH and NADPH), which are the most common redox cofactors of oxidoreductases, with regeneration rates of 59.00 μM/min for NADH and 40.99 μM/min for NADPH, ~ 84.3 and 24.7 times higher than those of bulk g-C3N4, respectively. The thin nanosheet structure of CN-ATCN facilitates the exposure of active sites to reactants and favors the diff usion of reactants and products. Upon conjugation of a thiophene moiety into the carbon nitride framework, the optical and photoelectric properties of CN-ATCN were considerably enhanced by an extended π-conjugation system in the frameworks and molecular type II heterojunctions formed between the incorporated and nonincorporated portions of CN-ATCN. Upon coupling NAD(P)H photoregeneration reaction by CN-ATCN with NAD(P)H-dependent enzymatic systems, sustainable synthesis of L-tert-leucine and styrene oxide was achieved with rates of 964 and 14.9 μM/h, respectively. 展开更多
关键词 Photobiocatalytic hybrid system Photocatalytic NAD(P)H regeneration Graphitic carbon nitride Solar-to-chemical conversion
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