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An efficient schedulability analysis based on worst-case interference time for real-time systems

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Science China(Information Sciences) 2024年第9期67卷 88-104页

作者： Hongbiao liu Mengfei YANG Lei QIAO xi CHEN Jian GONG School of Computer Science and Technology Xidian University China Academy of Space Technology Beijing Institute of Control Engineering

Real-time systems are widely implemented in the Internet of Things(IoT) and safety-critical systems, both of which have generated enormous social value. Aiming at the classic schedulability analysis problem in real-time systems, we proposed an exact Boolean analysis based on interference(EBAI) for schedulability analysis in real-time systems. EBAI is based on worst-case interference time(WCIT), which considers both the release jitter and blocking time of the task. We improved the efficiency of the three existing tests and provided a comprehensive summary of related research results in the field. Abundant experiments were conducted to compare EBAI with other related results. Our evaluation showed that in certain cases, the runtime gain achieved using our analysis method may exceed 73% compared to the stateof-the-art schedulability test. Furthermore, the benefits obtained from our tests grew with the number of tasks, reaching a level suitable for practical application. EBAI is oriented to the five-tuple real-time task model with stronger expression ability and possesses a low runtime overhead. These characteristics make it applicable in various real-time systems such as spacecraft, autonomous vehicles, industrial robots, and traffic command systems.

关键词： five-tuple real-time task model real-time system spacecraft Internet of Things exact schedulability analysis worst-case interference time

Experimental investigation on using CO_(2)/H_(2)O emulsion with high water cut in enhanced oil recovery

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Petroleum Science 2024年第2期21卷 974-986页

作者： xi-Dao Wu Peng xiao Bei liu Guang-Jin Chen Jian-Hua Pang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Ocean Intelligence Technology Center Shenzhen Institute of Guangdong Ocean UniversityShenzhen518120GuangdongChina

CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility ***,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fraction),while CO_(2) emulsion with high water cut has been rarely *** this paper,we carried out a comprehensive experimental study of using high water cut CO_(2)/H_(2)O emulsion for enhancing oil ***,a nonionic surfactant,alkyl glycosides(APG),was selected to stabilize CO_(2)/H_(2)O emulsion,and the corresponding morphology and stability were evaluated with a transparent PVT ***,plugging capacity and apparent viscosity of CO_(2)/H_(2)O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary ***,a high water cut(40 vol%) CO_(2)/H_(2)O emulsion was selected for flooding experiments in a long sand pack and a core sample,and the oil recovery,the rate of oil recovery,and the pressure gradients were *** results indicated that APG had a good performance on emulsifying and stabilizing CO_(2) *** inversion from H_(2)O/CO_(2) emulsion to CO_(2)/H_(2)O emulsion with the increase in water cut was ***_(2)/H_(2)O emulsions with lower water cuts presented higher apparent viscosity,while the optimal plugging capacity of CO_(2)/H_(2)O emulsion occurred at a certain water ***,the displacement using CO_(2)/H_(2)O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO_(2) in long sand pack and core tests,*** work may provide guidelines for EOR using CO_(2) emulsions with high water cut.

关键词： CO_(2)/H_(2)O emulsion High water cut CO_(2) mobility control Enhanced oil recovery

Insight into the selective separation of CO_(2)from biomass pyrolysis gas over metal-incorporated nitrogen-doped carbon materials:a first-principles study

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 1-12页

作者： Li Zhao xinru liu Zihao Ye Bin Hu Haoyu Wang Ji liu Bing Zhang qiang Lu National Engineering Research Center of New Energy Power Generation North China Electric Power UniversityBeijing102206China

The composition of biomass pyrolysis gas is complex,and the selective separation of its components is crucial for its further ***-incorporated nitrogen-doped materials exhibit enormous potential,whereas the relevant adsorption mechanism is still ***,16 metal-incorporated nitrogen-doped carbon materials were designed based on the density functional theory calculation,and the adsorption mechanism of pyrolysis gas components H2,CO,CO_(2),CH_(4),and C2H6 was *** results indicate that metal-incorporated nitrogen-doped carbon materials generally have better adsorption effects on CO and CO_(2)than on H_(2),CH_(4),and C_(2)H_(6).Transition metal Mo-and alkaline earth metal Mg-and Ca-incorporated nitrogen-doped carbon materials show the potential to separate CO and CO_(2).The mixed adsorption results of CO_(2)and CO further indicate that when the CO_(2)ratio is significantly higher than that of CO,the saturated adsorption of CO_(2)will precede that of ***,the three metal-incorporated nitrogen-doped carbon materials can selectively separate CO_(2),and the alkaline earth metal Mg-incorporated nitrogen-doped carbon material has the best *** study provides theoretical guidance for the design of carbon capture materials and lays the foundation for the efficient utilization of biomass pyrolysis gas.

关键词： CO_(2)capture biomass pyrolysis gas selective adsorption carbon materials first-principles

A unified Minorization-Maximization approach for estimation of general mixture models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 343-362页

作者： HUANG xi-fen liu Deng-ge ZHOU Yun-peng ZHU Fei School of Mathematics Yunnan Normal UniversityKunming 650092China Department of Statistics and Actuarial Science The University of Hong KongHong KongChina

The mixed distribution model is often used to extract information from heteroge-neous data and perform modeling *** the density function of mixed distribution is complicated or the variable dimension is high,it usually brings challenges to the parameter es-timation of the mixed distribution *** application of MM algorithm can avoid complex expectation calculations,and can also solve the problem of high-dimensional optimization by decomposing the objective *** this paper,MM algorithm is applied to the parameter estimation problem of mixed distribution *** method of assembly and decomposition is used to construct the substitute function with separable parameters,which avoids the problems of complex expectation calculations and the inversion of high-dimensional matrices.

关键词： MM algorithm mixed distribution model parameter estimation assembly decomposition tech-nology parameter separation

Therapeutic potentials of peptide-derived nanoformulations in atherosclerosis:present status and future directions

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International Journal of Smart and Nano Materials 2024年第3期15卷 610-651页

作者： Xue liu Weijiao Wang qiang Li Hongtao Niu Weili Zhang Department of Cardiovascular Medicine Yantaishan HospitalYantaiChina Department of Otolaryngology Yantaishan HospitalYantaiChina Department of Geriatric Medicine Yantaishan HospitalYantaiChina

Atherosclerosis is a severe cardiovascular disease followed by the accumulation of atherosclerotic plaques within the lumen of blood vessels resulting in reduced blood flow thus initiating a series of *** therapies for atherosclerosis encounter multiple chal-lenges,especially difficulty in precisely concentrating in certain affected regions and the potential for unwanted side ***,scientists are focused on developing nanoformulations for atherosclerosis diagnosis and ***-based nanomedi-cines improve conventional therapies by offering improved structural and therapeutic stability and enabling target-specific *** inherent biocompatibility and biodegradability additionally render them desirable materials intended for in vivo *** review manu-script aims to provide an in-depth overview of peptide-based nano-medicines for atherosclerosis,focusing on targeted cells like endothelial cells,macrophages,and monocytes and their interaction with different plaque ***,the manuscript also highlights the latest progress in multimodal techniques and provides a comprehensive overview of limitations associated with their practical implementation.

关键词： Atherosclerosis anti-atherosclerotic drugs bioavailability peptide-based nanomedicines drug targeting

Diagnostic Value of the Padua Score Combined with Thrombotic Biomarker Tissue Plasminogen Activator Inhibitor-1 (tPAI-1) Detection for the Risk of Deep Vein Thrombosis in Patients with Pulmonary Heart Disease

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Journal of Clinical and Nursing Research 2024年第8期8卷 137-144页

作者： xiaoyun Zhang xinlong xi Wenming Bian qiang liu Department of Cardiovascular Medicine People’s Hospital of PengzhouPengzhou 611930Sichuan ProvinceChina

This study explores the diagnostic value of combining the Padua score with the thrombotic biomarker tissue plasminogen activator inhibitor-1(tPAI-1)for assessing the risk of deep vein thrombosis(DVT)in patients with pulmonary heart *** patients often exhibit symptoms similar to venous thrombosis,such as dyspnea and bilateral lower limb swelling,complicating differential *** Padua Prediction Score assesses the risk of venous thromboembolism(VTE)in hospitalized patients,while tPAI-1,a key fibrinolytic system inhibitor,indicates a hypercoagulable *** data from hospitalized patients with cor pulmonale were retrospectively *** curves compared the diagnostic value of the Padua score,tPAI-1 levels,and their combined model for predicting DVT *** showed that tPAI-1 levels were significantly higher in DVT patients compared to non-DVT *** Padua score demonstrated a sensitivity of 82.61%and a specificity of 55.26%at a cutoff value of *** combined model had a significantly higher AUC than the Padua score alone,indicating better discriminatory ability in diagnosing DVT *** combination of the Padua score and tPAI-1 detection significantly improves the accuracy of diagnosing DVT risk in patients with pulmonary heart disease,reducing missed and incorrect *** study provides a comprehensive assessment tool for clinicians,enhancing the diagnosis and treatment of patients with cor pulmonale complicated by *** research should validate these findings in larger samples and explore additional thrombotic biomarkers to optimize the predictive model.

关键词： Padua prediction score Tissue plasminogen activator inhibitor-1(tPAI-1)detection Deep vein thrombosis(DVT) Pulmonary heart disease(cor pulmonale) Diagnostic accuracy

Climate warming is significantly influenced by rising summer maximum temperatures: insights from tree-ring evidence of the Western Tianshan Mountains, China

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Journal of Forestry Research 2024年第5期35卷 47-59页

作者： Meng Ren Yu liu Qiufang Cai qiang Li Huiming Song Changfeng Sun The State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061People’s Republic of China xi’an Institute for Innovative Earth Environment Research Xi’an 710061People’s Republic of China Institute of Desert Meteorology China Meteorological AdministrationÜrümqi 830002People’s Republic of China Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061People’s Republic of China School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China Qingdao National Laboratory for Marine Science and Technology Qingdao 266237People’s Republic of China

As one of the regions most affected by global cli-mate warming,the Tianshan mountains has experienced sev-eral ecological crises,including retreating glaciers and water *** warming in these mountains is considered mainly to be caused by increases in minimum temperatures and winter temperatures,while the influence of maximum temperatures is *** this study,a 300-year tree-ring chronology developed from the Western Tianshan Moun-tains was used to reconstruct the summer(June-August)maximum temperature(T_(max6-8))variations from 1718 to *** reconstruction explained 53.1% of the variance in the observed T_(max6-8).Over the past 300 years,the T_(max6-8)reconstruction showed clear interannual and decadal *** was a significant warming trend(0.18°C/decade)after the 1950s,which was close to the increasing rates of the minimum and mean *** increase in maximum temperature was also present over the whole Tianshan mountains and its impact on climate warming has *** T_(max6-8) variations in the Western Tianshan mountains were influenced by frequent volcanic eruptions combined with the influence of solar activity and the sum-mer North Atlantic *** study reveals that cli-mate warming is significantly influenced by the increase in maximum temperatures and clarifies possible driving mech-anisms of temperature variations in the Western Tianshan mountains which should aid climate predictions.

关键词： Tree rings Western Tianshan mountains Temperature change Climate warming

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Ultrafast investigation of room temperature valley polarization in“optical bilayer”WS_(2)

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Science China(Technological Sciences) 2024年第1期67卷 91-97页

作者： ZHAO LeYi WANG Hai liu TianYu LI FangFei ZHOU qiang WANG HaiYu Synergetic Extreme Condition High-Pressure Science Center State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

Monolayer transition metal dichalcogenides(TMDCs)have become a promising platform in valleytronics due to possessing the regulatable valley degrees of ***,as a result of the rapid intervalley scattering,it is difficult to measure the PL valley polarization of monolayer TMDCs at room temperature,which limits their application in valleytronics ***,we report a room temperature photoluminescence(PL)valley polarization up to 3.73%in an“optical bilayer”WS_(2)formed by transferring monolayer WS_(2)onto flat Ag ***,in the transient absorption(TA)measurements,a remarkably long valley depolarization lifetime is ***,we demonstrate the valley properties of such“optical bilayer”WS_(2)resemble actual bilayer WS_(2),in which the robust valley polarization can be attributed to the phonons depletion effect and the blocked interlayer hopping *** peculiar valley features in“optical bilayer”WS_(2)provide a particularly simple method to enhance valley control at room temperature.

关键词： valleytronics optical bilayer transient absorption tungsten disulfide

Ruthenium-Catalysed Asymmetric Intramolecular Isomerization/Esterification Reaction: Direct Synthesis of Chiral Dihydrocoumarins

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Chinese Journal of Chemistry 2024年第16期42卷 1828-1832页

作者： Lingzi Zhao Xuchao Wang Qing qiang xingwei Zhao Feipeng liu Shenci Lu Zi-qiang Rong Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SiFE)&Shaanxi Institute of Biomedical Materials and Engineering(SIBME)Northwestern Polytechnical University(NPU)127 West Youyi RoadXianShaanxi 710072China Honors College Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China

An asymmetric isomerization/intramolecular coupling reaction of allylic alcohols to synthesize chiral dihydrocoumarins was successfully accomplished through ruthenium *** method demonstrates a wide substrate applicability,excellent tolerance for various functional groups,and good enantioselectivities(up to 90%ee).It provides a convenient pathway to produce a diverse range ofstructurallydistinct chiral dihydrocoumarins ingoodefficiency.

关键词： Ruthenium catalysis Asymmetric isomerization Tandem reaction Chiral dihydrocoumarins Enantioselectivity