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Quantum speedup and limitations on matroid property problems

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Frontiers of Computer Science 2024年第4期18卷 189-196页

作者： Xiaowei huang Jingquan LUO Lvzhou LI Institute of Quantum Computing and Computer Theory School of Computer Science and EngineeringSun Yat-sen UniversityGuangzhou 510006China

Matroid theory has been developed to be a mature branch of mathematics and has extensive applications in combinatorial optimization,algorithm design and so *** the other hand,quantum computing has attracted much attention and has been shown to surpass classical computing on solving some computational ***,crossover studies of the two fields seem to be missing in the *** paper initiates the study of quantum algorithms for matroid property *** is shown that quadratic quantum speedup is possible for the calculation problem of finding the girth or the number of circuits(bases,flats,hyperplanes)of a matroid,and for the decision problem of deciding whether a matroid is uniform or Eulerian,by giving a uniform lower boundΩ■on the query complexity of all these *** the other hand,for the uniform matroid decision problem,an asymptotically optimal quantum algorithm is proposed which achieves the lower bound,and for the girth problem,an almost optimal quantum algorithm is given with query complexityO■.In addition,for the paving matroid decision problem,a lower boundΩ■on the query complexity is obtained,and an O■ quantum algorithm is presented.

关键词： quantum computing matroid quantum algorithm quantum query complexity

Analytical model for the sealant performance of tunnel gasketed joints based on multi-scale contact and percolation theories

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Underground Space 2024年第1期14卷 319-337页

作者： Jiachong Xie Xin huang Guolong Jin Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China State Key Laboratory of Geotechnical and Underground Engineering Ministry of EducationShanghai 200092China College of Civil Engineering&Architecture Xinjiang UniversityUrumqi 830047China China Shipbuilding NDRI Engineering Co. Ltd.Shanghai 200063China

The localised leakage in shield tunnels that mainly occurs at segment joints may induce other defects,which threatens operational *** obtain a universal solution for the sealant performance of gasketed joints,we proposed a novel analytical model based on the multiscale contact and percolation theories,in which the obtained percolation pressure and interfacial separation can be utilized to derive the critical water leakage pressure and leakage *** evolutionary process of leakage was divided into three stages(i.e.,the percolation,leakage and breakdown),which explicitly reveal the progressive hydraulic deterioration of gasketed *** gaskets still own partial waterproof capacity until the end of the leakage stage due to the remaining contact pressure at surface *** proposed model was first verified by several sets of experimental data,based on which the determination of three key model parameters(i.e.,self-sealing slope,sealing coefficient,and expel pressure)were discussed in *** parametric study indicates that the waterproof capacity is significantly affected by the joint opening,offset,and the surface roughness of the *** variation in waterproof capacity with joint opening is mainly due to the nonlinearity of the gasket’s modulus and self-sealing *** increase in joint offset can result in a lower waterproof capacity as well as a larger leakage ***’s surface roughness affects the percolation pressure and interfacial separation,which contributes to the long-term sealant performance.

关键词： Shield tunnel Gasketed joint Sealant performance Hydraulic deterioration Percolation theory Surface roughness Leakage rate

Effect of Inter-Stage Pressure on Performances of Two-Stage Transcritical CO2 Refrigeration Cycle with Dedicated Absorption Dual-Subcooling and Mechanical Recooling

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Journal of Thermal Science 2024年第06期33卷 2179-2189页

作者： LI Zeyu huang Caoxuheng YIN Jianhui School of Electric Power South China University of Technology Guangdong Province Key Laboratory of High Efficient and Clean Energy Utilization South China University of Technology Guangdong Province Engineering Research Center of High Efficient and Low Pollution Energy Conversion Ningbo Jetron Technology Co.Ltd.

The two-stage transcritical CO2refrigeration cycle with dedicated dual-subcooling and mechanical recooling is *** inter-stage pressure is critical for such cycle performances;however,it has not been studied ***,the research aim is to disclose the effect of inter-stage pressure on performances of the proposed *** main work consists of four ***,the comparative study is performed to display advantages of the proposed ***,the key temperatures,heat and power consumptions as well as performance indicators for different inter-stage pressures are analyzed in detail,based on the parametric ***,the optimal inter-stage pressure for different conditions is obtained by the nonlinear direct search ***,the economic performance is *** is found that the compressor power of the proposed cycle drops by 12%,and the working temperature lower limit is reduced by 11℃.Furthermore,it is considered that the optimal inter-stage pressure is insensitive to the heat source *** novelty lies in illustrating the effect of inter-stage pressure,obtaining trends of the optimal value,and pointing out the system *** paper is favorable for design and operation optimization of the proposed system.

关键词： CO2 refrigeration dedicated absorption subcooling recooling thermodynamics two-stage cycle

Rice canopy temperature is affected by nitrogen fertilizer

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Journal of Integrative Agriculture 2024年第3期23卷 824-835页

作者： Min Jiang Zhang Chen Yuan Li Xiaomin huang Lifen huang Zhongyang Huo Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Agricultural College Yangzhou UniversityYangzhou 225009China Jiangsu Co-lnnovation Center for Modern Production Technology of Grain Crops Yangzhou UniversityYangzhou 225009China

Canopy temperature strongly influences crop yield formation and is closely related to plant physiological ***, the effects of nitrogen treatment on canopy temperature and rice growth have yet to be comprehensively examined. We conducted a two-year field experiment with three rice varieties(HD-5, NJ-9108, and YJ-805) and three nitrogen treatments(zero-N control(CK), 200 kg ha~(–1)(MN), and 300 kg ha~(–1)(HN)). We measured canopy temperature using a drone equipped with a high-precision camera at the six stages of the growth period. Generally,canopy temperature was significantly higher for CK than for MN and HN during the tillering, jointing, booting, and heading stages. The temperature was not significantly different among the nitrogen treatments between the milky and waxy stages. The canopy temperature of different rice varieties was found to follow the order: HD-5>NJ-9108>YJ-805, but the difference was not significant. The canopy temperature of rice was mainly related to plant traits, such as shoot fresh weight(correlation coefficient r=–0.895), plant water content(–0.912), net photosynthesis(–0.84), stomatal conductance(–0.91), transpiration rate(–0.90), and leaf stomatal area(–0.83). A structural equation model(SEM) showed that nitrogen fertilizer was an important factor affecting the rice canopy *** study revealed:(1) A suite of plant traits was associated with the nitrogen effects on canopy temperature,(2) the heading stage was the best time to observe rice canopy temperature, and(3) at that stage, canopy temperature was negatively correlated with rice yield, panicle number, and grain number per panicle. This study suggests that canopy temperature can be a convenient and accurate indicator of rice growth and yield prediction.

关键词： canopy temperature rice physiological and biochemical characteristics yield

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Single-atom catalysis:a promising avenue for precisely controlling reaction pathways

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Frontiers of Chemical Science and Engineering 2024年第7期18卷 97-120页

作者： Xiaobo Yang Xuning Li Yanqiang huang State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Single-atom catalysts (SACs), characterized by exceptionally high atom efficiency, have garnered significant attention across various catalytic reactions. Recent studies have showcased SACs with robust capabilities for precise catalysis, specifically targeting reactions along designated pathways. This review focuses on the advances in the precise activation and reconstruction of chemical bonds on SACs, including precise activation of C–O and C–H bonds and selective couplings involving C–C and C–N bonds. Our discussion begins with a thorough exploration of the factors that render SACs skilled in precise catalytic processes, encompassing the narrow d-band electronic state of single atom site resulting in the adsorption tendency, isolate site resulting in unique adsorption structure, and synergy effect of a single atom site with its neighbors. Subsequently, we elaborate on the applications of SACs in electrocatalysis and thermocatalysis including four prominent reactions, namely, electrochemical CO_(2) reduction, urea electrochemical synthesis, CO_(2) hydrogenation, and CH4 activation. Then the concept of rational design of SACs for precisely controlling reaction pathways is discussed from the aspects of pore structure design, support-metal strong interaction, and support hydrophilic/hydrophobic. Finally, we summarize the challenges encountered by SACs in the field of precise catalytic processes and outline prospects for their further development in this domain.

关键词： single atom catalysts selective oxidation CO_(2)RR bond coupling

Gria:an efficient deterministic concurrency control protocol

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Frontiers of Computer Science 2024年第4期18卷 25-37页

作者： Xinyuan WANG Yun PENG Hejiao huang School of Computer Science and Technology Harbin Institute of TechnologyShenzhen 518055China Institute of Artificial Intelligence and Blockchain Guangzhou UniversityGuangzhou 510006China

Deterministic databases are able to reduce coordination costs in a *** property has fostered a significant interest in the design of efficient deterministic concurrency control ***,the state-of-the-art deterministic concurrency control protocol Aria has three ***,it is impractical to configure a suitable batch size when the read-write set is ***,Aria running in low-concurrency scenarios,e.g.,a single-thread scenario,suffers from the same conflicts as running in high-concurrency ***,the single-version schema brings write-after-write *** address these issues,we propose Gria,an efficient deterministic concurrency control *** has the following ***,the batch size of Gria is ***,Gria’s conflict probability in low-concurrency scenarios is lower than that in high-concurrency ***,Gria has no write-after-write conflicts by adopting a multi-version *** further reduce conflicts,we propose two optimizations:a reordering mechanism as well as a rechecking *** evaluation result on two popular benchmarks shows that Gria outperforms Aria by 13x.

关键词： deterministic concurrency control transaction processing

Robust AUC maximization for classification with pairwise confidence comparisons

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Frontiers of Computer Science 2024年第4期18卷 73-83页

作者： Haochen SHI Mingkun XIE Shengjun huang College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China MIIT Key Laboratory of Pattern Analysis and Machine Intelligence Nanjing 211106China

Supervised learning often requires a large number of labeled examples,which has become a critical bottleneck in the case that manual annotating the class labels is *** mitigate this issue,a new framework called pairwise comparison(Pcomp)classification is proposed to allow training examples only weakly annotated with pairwise comparison,i.e.,which one of two examples is more likely to be *** previous study solves Pcomp problems by minimizing the classification error,which may lead to less robust model due to its sensitivity to class *** this paper,we propose a robust learning framework for Pcomp data along with a pairwise surrogate loss called *** provides an unbiased estimator to equivalently maximize AUC without accessing the precise class ***,we prove the consistency with respect to AUC and further provide the estimation error bound for the proposed *** studies on multiple datasets validate the effectiveness of the proposed method.

关键词： method pairwise weakly

Recent progress in side chain engineering of Y-series non-fullerene molecule and polymer acceptors

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Science China Chemistry 2024年第3期67卷 788-805页

作者： Li Tian Chunchen Liu Fei huang School of Materials Science and Engineering Henan University of TechnologyZhengzhou 450001China Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou 510640China

Organic solar cells(OSCs) have drawn considerable attention in the last decade due to the great potential of light weight,flexibility, and low-cost solution processing. Particularly, Y-series non-fullerene acceptors(NFAs) including small molecular acceptors(SMAs) and polymerized small molecular acceptors(PSMAs) have become research hot spots due to their excellent power conversion efficiency. Side chain engineering is crucial to adjust the solubility and crystallinity of NFAs, which will significantly affect the morphology of active layers and the efficiency of OSCs. However, the understanding of side chain engineering on NFAs is still limited and lacks a systematic review. This review aims to provide a brief summary of the recent developments in side chain engineering of NFAs, with a special focus on the design and application of Y-series SMAs and PSMAs for high-efficiency non-fullerene organic solar cells(NF-OSCs). In addition, the review also points out challenges and provides useful guidance regarding side chain regulation for Y-series NFAs.

关键词： organic solar cell Y-series non-fullerene acceptors side chain engineering

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WNT7A promotes tumorigenesis of head and neck squamous cell carcinoma via activating FZD7/JAK1/STAT3 signaling

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International Journal of Oral Science 2024年第1期16卷 85-96页

作者： Qingling huang Yi Xiao Ting Lan Youguang Lu Li huang Dali Zheng Department of Biochemistry and Molecular Biology School of Basic Medical SciencesFujian Medical UniversityFuzhouChina Fujian Key Laboratory of Oral Diseases School and Hospital of StomatologyFujian Medical UniversityFuzhouChina Department of Preventive Dentistry School and Hospital of StomatologyFujian Medical UniversityFuzhouChina Department of Dentistry The First Affiliated Hospital of Fujian Medical UniversityFuzhouChina

Wnt signaling are critical pathway involved in organ development, tumorigenesis, and cancer progression. WNT7A, a member of the Wnt family, remains poorly understood in terms of its role and the underlying molecular mechanisms it entails in head and neck squamous cell carcinoma (HNSCC). According to the Cancer Genome Atlas (TCGA), transcriptome sequencing data of HNSCC, the expression level of WNT7A in tumors was found to be higher than in adjacent normal tissues, which was validated using Real-time RT-PCR and immunohistochemistry. Unexpectedly, overexpression of WNT7A did not activate the canonical Wnt-β-catenin pathway in HNSCC. Instead, our findings suggested that WNT7A potentially activated the FZD7/JAK1/STAT3 signaling pathway, leading to enhanced cell proliferation, self-renewal, and resistance to apoptosis. Furthermore, in a patient-derived xenograft (PDX) tumor model, high expression of WNT7A and phosphorylated STAT3 was observed, which positively correlated with tumor *** findings underscore the significance of WNT7A in HNSCC progression and propose the targeting of key molecules within the FZD7/JAK1/STAT3 pathway as a promising strategy for precise treatment of HNSCC.

关键词： WNT squamous tumorigenesis

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