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Structured Multi-Head Attention Stock Index Prediction Method Based Adaptive Public Opinion Sentiment Vector
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作者 Cheng Zhao zhe peng +2 位作者 Xuefeng Lan Yuefeng Cen Zuxin Wang 《Computers, Materials & Continua》 SCIE EI 2024年第1期1503-1523,共21页
The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment ... The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment risk.The quantification of investment sentiment indicators and the persistent analysis of their impact has been a complex and significant area of research.In this paper,a structured multi-head attention stock index prediction method based adaptive public opinion sentiment vector is proposed.The proposedmethod utilizes an innovative approach to transform numerous investor comments on social platforms over time into public opinion sentiment vectors expressing complex sentiments.It then analyzes the continuous impact of these vectors on the market through the use of aggregating techniques and public opinion data via a structured multi-head attention mechanism.The experimental results demonstrate that the public opinion sentiment vector can provide more comprehensive feedback on market sentiment than traditional sentiment polarity analysis.Furthermore,the multi-head attention mechanism is shown to improve prediction accuracy through attention convergence on each type of input information separately.Themean absolute percentage error(MAPE)of the proposedmethod is 0.463%,a reduction of 0.294% compared to the benchmark attention algorithm.Additionally,the market backtesting results indicate that the return was 24.560%,an improvement of 8.202% compared to the benchmark algorithm.These results suggest that themarket trading strategy based on thismethod has the potential to improve trading profits. 展开更多
关键词 Public opinion sentiment structured multi-head attention stock index prediction deep learning
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一种有助于稳定锂金属循环的富氟化位点框架结构 被引量:6
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作者 王木钦 彭哲 +5 位作者 林欢 李振东 刘健 任重民 何海勇 王德宇 《物理化学学报》 SCIE CAS CSCD 北大核心 2021年第1期126-135,共10页
锂金属是下一代高能量密度二次电池的理想负极材料,然而它的应用仍然受制于较差的循环稳定性。近期,二维氟化界面被广泛用于改善锂金属负极的成核机制、沉积形貌和循环稳定性。本工作通过将体积缩小化的氟化石墨颗粒与锂离子传导网络结... 锂金属是下一代高能量密度二次电池的理想负极材料,然而它的应用仍然受制于较差的循环稳定性。近期,二维氟化界面被广泛用于改善锂金属负极的成核机制、沉积形貌和循环稳定性。本工作通过将体积缩小化的氟化石墨颗粒与锂离子传导网络结合,获得了一种富氟化位点的三维框架结构。实验结果证明此类三维氟化结构可显著提升锂金属负极在不同电流密度和容量下的循环稳定性,且优于二维氟化界面结构。通过本工作的研究,证明了相较于单纯的二维氟化界面,三维锂离子传导网络和富氟化位点的合理结合可以成为一种改进的界面结构用于锂金属负极保护,为高能量密度锂金属电池的负极保护提供了新的设计思路。 展开更多
关键词 锂金属电池 锂金属负极 氟化石墨 固液界面 库伦效率
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A strongly interactive adatom/substrate interface for dendrite-free and high-rate Li metal anodes 被引量:3
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作者 Shun Li zhendong Li +5 位作者 Liyuan Huai Mingming Ma Kailin Luo Jiahe Chen Deyu Wang zhe peng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第11期179-190,I0004,共13页
Lithium (Li) metal is considered as one of the most promising anode materials to build next-generation high-energy–density batteries. Nonetheless, dendritic Li deposition has dramatically hindered the practical appli... Lithium (Li) metal is considered as one of the most promising anode materials to build next-generation high-energy–density batteries. Nonetheless, dendritic Li deposition has dramatically hindered the practical applications of Li metal batteries (LMBs). Uniformizing Li deposition is a prerequisite to achieve safe and practical LMBs. Herein, an underpotential deposition (UPD) process is first proposed to alter the kinetic and uniformity of Li deposition morphology. Based on the strong interaction between the Li adatoms and manganese (Mn) based substrate, a competition between the UPD and bulk Li deposition is observed, on which the predominance of the UPD scenario tends to uniformize Li nucleation and deposition by the surface coverage of Li monolayers at potentials that are more positive than the Nernst potential of Li metal. Inspired by this process, an advanced hybrid Mn-graphene oxide structure is developed for Li protection, not only enabling dendrite-free Li anodes for high-capacity and -current density cycling, but also improving the interfacial kinetic of Li metal anodes at subzero temperatures, showing potential applicability in low temperature conditions. 展开更多
关键词 Lithium metal battery Lithium metal anode Lithium dendrite Bulk lithium deposition Underpotential deposition
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Change in Ecosystem Service Value Arising from Land Consolidation Planning in Anhui Province 被引量:2
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作者 Shaojia CAO Chen LI +2 位作者 Shuhua CAO zhe peng Lingli YANG 《Asian Agricultural Research》 2013年第1期13-16,共4页
The evaluation of change in ecosystem service value arising from land consolidation planning is an important aspect of environmental impact assessment of land consolidation. By estimating the change in ecosystem servi... The evaluation of change in ecosystem service value arising from land consolidation planning is an important aspect of environmental impact assessment of land consolidation. By estimating the change in ecosystem service value before and after the implementation of land consolidation planning, it is able to quantitatively describe the change in ecosystem service value arising from land consolidation planning, so as to provide a quantitative basis for the environmental impact assessment of land consolidation. Taking the case of Anhui Province, the authors developed the equivalency factor table of ecosystem service value, to determine the economic value of single equivalency factor of ecological service value in the study area, calculate per unit area of ecological service value of land ecosystem in the study area, and research the change in ecosystem service value before and after the implementation of land consolidation planning in Anhui Province. The results show that after the implementation of a new round of land consolidation planning in Anhui Province, the total ecosystem service value may decrease to some extent, the farmland ecosystem service value substantially increases, while water body ecosystem service value greatly decreases. 展开更多
关键词 ECOSYSTEM service VALUE LAND CONSOLIDATION plannin
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Li^(+)Solvation Mediated Interfacial Kinetic of Alloying Matrix for Stable Li Anodes
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作者 Xingyi Wang Kailin Luo +6 位作者 Lixin Xiong Tengpeng Xiong zhendong Li Jie Sun Haiyong He Chuying Ouyang zhe peng 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期70-80,共11页
Severe lithium(Li)dendrite growth caused by the uneven overpotential deposition is a formidable challenge for high energy density Li metal batteries(LMBs).Herein,we investigate a synergetic interfacial kinetic to regu... Severe lithium(Li)dendrite growth caused by the uneven overpotential deposition is a formidable challenge for high energy density Li metal batteries(LMBs).Herein,we investigate a synergetic interfacial kinetic to regulate Li deposition behavior and stabilize Li metal anode.Through constructing Li alloying matrix with a bi-functional silver(Ag)-Li_(3)N blended interface,fast Li^(+)conductivity and high Li affinity can be achieved simultaneously,resulting in both decreased Li nucleation and mass transfercontrolled overpotentials.Beyond these properties,a more important feature is demonstrated herein;that is,the inward diffusion depth of the Li adatoms inside of the Ag site can be restricted by the Li^(+)solvation structure in a highly coordinating environment.The latter feature can ensure the durability of the operational Ag sites,thereby elongating the Li protection ability of the Ag-Li_(3)N interface greatly.This work provides a deep insight into the synergetic effect of functional alloying structure and Li^(+)solvation mediated interfacial kinetic on Li metal protection. 展开更多
关键词 Li^(+)solvation structure Li-Ag alloy lithium metal anode lithium metal batteries SEI
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Diagnosis and treatment of mixed infection of hepatic cystic and alveolar echinococcosis:Four case reports
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作者 Ji-De A Jin-Ping Chai +4 位作者 Hao Wang Wei Gao zhe peng Shun-Yun Zhao Xiang-Ren A 《World Journal of Clinical Cases》 SCIE 2020年第17期3911-3919,共9页
BACKGROUND Mixed infection of hepatic cystic and alveolar echinococcosis is extremely rare.This article reveals the typical imaging manifestations of cystic and alveolar echinococcosis and investigates the diagnosis a... BACKGROUND Mixed infection of hepatic cystic and alveolar echinococcosis is extremely rare.This article reveals the typical imaging manifestations of cystic and alveolar echinococcosis and investigates the diagnosis and surgical experience of mixed infection of hepatic cystic and alveolar echinococcosis.CASE SUMMARY From January 2017 to May 2019,4 cases with rare mixed infection of hepatic cystic and alveolar echinococcosis were admitted and treated by the Division of General Surgery of Qinghai Provincial People’s Hospital.Three of the patients occasionally had upper abdominal discomfort,but it did not affect their daily lives.However,hepatic echinococcosis was found in one patient by physical examination,and the patient had no discomfort.All 4 cases were Tibetans who had lived in pastoral areas of southern Qinghai for a long time.Enzyme-linked immunosorbent assay for echinococcosis was positive for all patients.Moreover,abdominal computed tomography showed typical imaging manifestations of cystic and alveolar echinococcosis including coexisting"honeycomb sign,"and"spotted calcification."Three of the patients underwent radical resection,and 1 case underwent palliative resection.All 4 patients developed different types of surgical complications after the operation,but all of them recovered and were discharged after symptomatic treatment.CONCLUSION There are no problems diagnosing mixed infection of hepatic cystic and alveolar echinococcosis.The difficulties involve preoperative evaluation and treatment of surgical complications. 展开更多
关键词 Cystic and alveolar echinococcosis Mixed infection Case report
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Countermeasures for China's Ecological Environment Construction in Land Reclamation
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作者 Chen LI Xinfeng LIU +2 位作者 zhe peng Tao SI Lingfeng KONG 《Asian Agricultural Research》 2013年第2期36-38,共3页
Basic situation of the current ecological environment construction in land consolidation and rehabilitation of China is introduced. The related advanced experience abroad is summarized from mainly four aspects, namely... Basic situation of the current ecological environment construction in land consolidation and rehabilitation of China is introduced. The related advanced experience abroad is summarized from mainly four aspects, namely policy, system as well as subject development, planning guidance, design method of project planning and engineering study, and practical countermeasures to China's ecological environment construction in land reclamation are proposed. In terms of policy, system and subject, relevant regulations, policies and system construction should be strengthened and the framework of policy, system and subject development in ecological landscape construction of China's land reclamation should be proposed, integrating ecological environment construction into land reclamation. At the level of strategic planning, the spatial layout and construction key points of green infrastructure in land reclamation of "urban multi-functional developing region, eastern economic developed region, central modern agricultural region and northwestern ecological fragile region" should be achieved. At the level of project planning design, ecological principles, sustainable landscape design principles and vernacular landscape design methods are to be integrated into the planning procedure to form operable technique regulations or introductions. At the level of engineering design, engineering technique system, standards and regulations of ditches, roads, forests and channels with local distinctions should be formulated according to the characters and strategic demands of urbanization, industrialization, agriculture modernization and ecological environment preservation in different regions. 展开更多
关键词 LAND RECLAMATION ECOLOGICAL ENVIRONMENT Constructi
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Inter-comparisons of VOC oxidation mechanisms based on box model:A focus on OH reactivity 被引量:3
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作者 Xiaoyun Yang Bin Yuan +5 位作者 zhe peng Yuwen peng Caihong Wu Suxia Yang Jin Li Min Shao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第4期286-296,共11页
Volatile organic compounds(VOCs)oxidation processes play a very important role in atmospheric chemistry,and the chemical reactions are expressed in various manners in chemical mechanisms.To gain an improved understand... Volatile organic compounds(VOCs)oxidation processes play a very important role in atmospheric chemistry,and the chemical reactions are expressed in various manners in chemical mechanisms.To gain an improved understanding of VOCs evolution during oxidation processes and evaluate the discrepancies of VOCs oxidation schemes among different mechanisms,we used the total VOC reactivity as a diagnostic and evaluated tool to explore the differences for six widely used chemical mechanisms.We compared the total VOC reactivity evolution under high-NO_(x)xconditions for several sets of precursors,including n-pentane,toluene,ethene,isoprene and a mixture of 57 Photochemical Assessment Monitoring Stations(PAMS)species in a 0-D photochemical box model.Inter-comparison of total VOC reactivity of individual precursor simulations showed discrepancies to different extent of the oxidation schemes among the studied mechanisms,which are mainly attributed to the different lumping approaches for organic species.The PAMS simulation showed smaller discrepancy than individual precursor cases in terms of total VOC reactivity.SAPRC07 and RACM2 performances are found to better match the MCM for simulation of total VOC reactivity.Evidences suggest that the performance in simulating secondary organic products,OH concentrations and NO_(x)concentrations are related to the OH reactivity discrepancies among various chemical mechanisms.Information in this study can be used in selection of chemical mechanisms to better model OH reactivity in different environments.The results in this study also provide directions to further improve the ability in modelling total VOC reactivity with the chemical mechanisms. 展开更多
关键词 VOCs Box model Chemical mechanism Total VOC reactivity VOC oxidation
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Menstrual irregularity,pregnancy outcomes,and birth outcomes in patients with systemic lupus erythematosus of childbearing age in China:a multicenter cross-sectional study 被引量:2
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作者 Yuke Hou Jiayang Jin +5 位作者 Liang Luo Yuchao Zhong zhe peng Ziyi Song Chun Li Xuewu Zhang 《Chinese Medical Journal》 SCIE CAS CSCD 2023年第23期2886-2888,共3页
To the Editor:Systemic lupus erythematosus(SLE)is an autoimmune disease that tends to affect females of childbearing age.There are nearly 4 million people in China currently suffering from SLE,which can cause multiple... To the Editor:Systemic lupus erythematosus(SLE)is an autoimmune disease that tends to affect females of childbearing age.There are nearly 4 million people in China currently suffering from SLE,which can cause multiple organ damage in its early stages and seriously affect patients’quality of life.[1-3]Menstrual disorders are common in SLE patients and vary from heavy menstrual bleeding to amenorrhea.The etiology of menstrual irregularities includes the disease activity itself,glucocorticoids(GCs)treatment,and the use of some immunosuppressants.[4]This multicenter,cross-sectional,web-based observational study investigated menstrual irregularity,pregnancy outcomes,and birth outcomes on SLE patients across China.The research was approved by the Ethics Committee of Peking University People’s Hospital,China(No.2019PHB253-01).The patients were informed that consent was implied with completion of the questionnaire,and the process was anonymous and voluntary. 展开更多
关键词 PATIENTS sectional BIRTH
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CO_(2)-promoted transfer-free growth of conformal graphene
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作者 Ruojuan Liu zhe peng +10 位作者 Xiaoli Sun Zhaolong Chen Zhi Li Haina Ci Bingzhi Liu Yi Cheng Bei Jiang Junxiong Hu Wanjian Yin Jingyu Sun Zhongfan Liu 《Nano Research》 SCIE EI CSCD 2023年第5期6334-6342,共9页
Gaseous promotors have readily been adopted during the direct synthesis of graphene over insulators to enhance the growth quality and/or boost the growth rate.The understanding of the real functions of carbon-containi... Gaseous promotors have readily been adopted during the direct synthesis of graphene over insulators to enhance the growth quality and/or boost the growth rate.The understanding of the real functions of carbon-containing promotors has still remained elusive.In this study,we identify the critical roles of a representative CO_(2)promotor played in the direct growth of graphene.The comparative experimental trials validate CO_(2)as an effective modulator to decrease graphene nucleation density,improve growth kinetics,mitigate adlayer formation.The first-principles calculations illustrate that the generation of gas-phase OH species in CO_(2)-assisted system helps decrease the energy barriers of CH4 decomposition and carbon attachment to the growth front,which might be the key factor to allow high-quality direct growth.Such a CO_(2)-promoted strategy enables the conformal coating of graphene film over curved insulators,where the sheet resistance of grown graphene on quartz reaches as low as 1.26 kΩ·sq^(−1)at an optical transmittance of~95.8%.The fabricated endoscope lens based on our conformal graphene harvests an apoptosis of 82.8%for noninvasive thermal therapy.The work presented here is expected to motivate further investigations in the controllable growth of high-quality graphene on insulating substrates. 展开更多
关键词 chemical vapor deposition GRAPHENE carbon dioxide transfer-free growth promotor CONFORMAL
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Anthracene Modified by Aldehyde Groups Exhibiting Aggregation-Induced Emission Properties
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作者 zhe peng Zhi Wang +4 位作者 Bin Tong Yingchun Ji Jianbing Shi Junge Zhi Yuping Dong 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2016年第11期1071-1075,共5页
In order to get an easy way to achieve the transformation from aggregation-caused quenching luminophores (ACQphores) to aggregation-induced emission luminogens (AIEgens), we took aldehyde groups as the modifying g... In order to get an easy way to achieve the transformation from aggregation-caused quenching luminophores (ACQphores) to aggregation-induced emission luminogens (AIEgens), we took aldehyde groups as the modifying group to decorate anthracene. The fluorescence performances of 9-anthraldehyde (AnA) and 9,10-anthracenedicarboxaldehyde (AnDA) in solution and aggregated state were studied. We found out that the aldehyde group can transform anthracene with aggregation-caused quenching properties to AIEgen. The single-crystal structures analy- sis of AnA and AnDA showed that their structure characteristics are responsible for the AIE properties of AnA and AnDA. On one hand, the aldehyde group can cause steric effects to lower intermolecular n-π packing style in aggregated state. On the other hand, intermolecular H-bonding interactions can restrict the intramolecular rotation and suppress internal charge transfer. These results may supply a new simple method for the transformation from ACQphores to AIEgens on the point of the molecular design. 展开更多
关键词 aggregation-induced emission aldehyde group organic luminescent materials MECHANISM HYDROGEN-BONDING
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