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Power Allocation for SE Maximization in Uplink Massive MIMO System Under Minimum Rate Constraint

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China Communications 2024年第3期21卷 104-117页

作者： wang Hui Yu Xiangbin Liu Fuyuan Bai Jiawei College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

In this paper,we optimize the spectrum efficiency(SE)of uplink massive multiple-input multiple-output(MIMO)system with imperfect channel state information(CSI)over Rayleigh fading *** SE optimization problem is formulated under the constraints of maximum power and minimum rate of each ***,we develop a near-optimal power allocation(PA)scheme by using the successive convex approximation(SCA)method,Lagrange multiplier method,and block coordinate descent(BCD)method,and it can obtain almost the same SE as the benchmark scheme with lower *** this scheme needs three-layer iteration,a suboptimal PA scheme is developed to further reduce the complexity,where the characteristic of massive MIMO(i.e.,numerous receive antennas)is utilized for convex reformulation,and the rate constraint is converted to linear *** suboptimal scheme only needs single-layer iteration,thus has lower complexity than the near-optimal ***,we joint design the pilot power and data power to further improve the performance,and propose an two-stage algorithm to obtain joint *** results verify the effectiveness of the proposed schemes,and superior SE performance is achieved.

关键词： imperfect CSI massive MIMO minimum rate constraint power allocation spectral efficiency

Carbonation of Pure Minerals in Portland Cement:Evolution in Products as a Function of Water-to-solid Ratio

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1214-1222页

作者： XIONG Kun SHANG Xiaopeng LI Hongyan wang Dan Zhengzhou Lutong Highway Construction Co. Ltd.Zhengzhou 450052China (Special Glass Key Lab of Hainan Province)&(State Key Laboratory of Marine Resource Utilization in South China Sea) Hainan UniversityHaikou 570228China Department of Architectural Engineering Shandong Urban Construction Vocational CollegeJinan 250103China (State Key Laboratory of High Performance Civil Engineering Materials Jiangsu Sobute New Materials Co.Ltd.)&(School of Material Science and EngineeringSoutheast UniversityNanjing 211189China)

Minerals in Portland cement including tricalcium silicate(C_(3)S),β-dicalcium silicate(β-C_(2)S),tricalcium aluminate(C_(3)A),and tetracalcium ferroaluminate(C_(4)AF),show a significantly different activity and product evolution for CO_(2)curing at various water-to-solid *** pure minerals were synthesized and subject to CO_(2)curing in this study to make an in-depth understanding for the carbonation properties of cement-based *** showed that the optimum water-to-solid ratios of C_(3)S,β-C_(2)S,C_(3)A and C_(4)AF were 0.25,0.15,0.30 and 0.40 for carbonation,corresponding to 2 h carbonation degree of 38.5%,38.5%,24.2%,and 21.9%,*** produced calcite duringβ-C_(2)S carbonation decreased as the water-to-solid ratio increased,with an increase in content of metastable CaCO_(3)of vaterite and *** thermodynamic stability of CaCO_(3)produced during carbonation was C_(3)A>C_(4)AF>β-C_(2)S>C_(3)*** carbonation degree of Portland cement was predicted based on the results of pure minerals and the composition of cement,and the error of predicted production of CaCO_(3)was only 1.1%,which provides a potential method to predict carbonation properties of systems with a complex mineral composition.

关键词： accelerated carbonation portland cement calcium carbonate water-to-solid ratio

Material point method simulation of hydro-mechanical behaviour in twophase porous geomaterials: A state-of-the-art review

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2341-2350页

作者： Xiangcou Zheng Shuying wang Feng Yang Junsheng Yang School of Civil Engineering Central South UniversityChangsha410075China Geo-Engineering Section Faculty of Civil Engineering and GeosciencesDelft University of TechnologyDelftthe Netherlands

The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large *** this paper,we survey the current state-of-the-art in the MPM simulation of hydro-mechanical behaviour in two-phase porous *** review covers the recent advances and developments in the MPM and their extensions to capture the coupled hydro-mechanical problems involving large *** focus of this review is aiming at providing a clear picture of what has or has not been developed or implemented for simulating two-phase coupled large deformation problems,which will provide some direct reference for both practitioners and researchers.

关键词： Coupled problems Hydro-mechanical behaviour Large deformation Material Point Method(MPM)

Maximum Principle for Stochastic Control System with Elephant Memory and Jump Diffusion

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Journal of Systems Science & Complexity 2024年第4期37卷 1392-1412页

作者： FENG Siqi GAO Lei wang Guangchen XIAO Hua School of Control Science and Engineering Shandong UniversityJinan 250061China School of Economics Shandong UniversityJinan 250100China School of Mathematics and Statistics Shandong UniversityWeihai 264209China

Motivated by a duopoly game problem,the authors study an optimal control problem where the system is driven by Brownian motion and Poisson point process and has elephant memory for the control variable and the state ***,the authors establish the unique solvability of an anticipated backward stochastic differential equation,derive a stochastic maximum principle,and prove a verification theorem for the aforementioned optimal control ***,the authors generalize these results to nonzero-sum stochastic differential game ***,the authors apply the theoretical results to the duopoly game problem and obtain the corresponding Nash equilibrium solution.

关键词： Anticipated backward stochastic differential equation elephant memory Fréchet derivative maximum principle stochastic delayed differential equation

Enhancing transboundary natural tourism resources governance:unveiling the spatial pattern and its influencing factors

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Journal of Mountain Science 2024年第3期21卷 973-986页

作者： ZHANG Shengrui ZHANG Tongyan JU Hongrun wang yingjie Management College Ocean University of ChinaQingdao 266100China School of Tourism and Geography Science Qingdao UniversityQingdao 266071China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Tourism resources that span provincial boundaries in China play a pivotal role in regional development,yet effective governance poses persistent *** study addresses this issue by constructing a comprehensive database of transboundary natural tourism resources(TNTR)through amalgamation of diverse data *** the Getis-Ord Gi^(*),kernel density estimation,and geographical detectors,we scrutinize the spatial patterns of TNTR,focusing on both named and unnamed entities,while exploring the influencing *** findings reveal 7883 identified TNTR in China,with mountain tourism resources emerging as the predominant *** provinces,Hunan boasts the highest count,while Shanghai exhibits the *** China demonstrates a pronounced clustering trend in TNTR distribution,with the spatial arrangement of biological landscapes appearing more random compared to geological and water *** China,characterized by intricate terrain,exhibits fewer TNTR,concurrently unveiling a significant presence of unnamed natural tourism ***,administrative segmentation influences TNTR development,generating disparities in regional goals,developmental stages and intensities,and management *** response to these variations,we advocate for strengthening the naming of the unnamed transboundary tourism resources,constructing a geographic database of TNTR for government and establishing a collaborative management mechanism based on TNTR *** research contributes to elucidating the intricate landscape of TNTR,offering insights for tailored governance strategies in the realm of cross-provincial tourism resource management.

关键词： Transboundary natural tourism resources(TNTR) Spatial difference Spatial autocorrelation Governance optimization China

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多接收者证书基可搜索加密方案

计算机学报 2024年第3期47卷 544-557页

作者：刘行明洋王晨豪赵一长安大学信息工程学院西安710064

可搜索加密作为一种加密原语,允许用户在云存储服务器中搜索文件的同时确保原始文件的机密性.证书基可搜索加密在实现密文检索的基础上,解决了证书管理、密钥托管、安全信道等问题.然而,已有的证书基可搜索加密要么使用耗时的双线性映... 详细信息

可搜索加密作为一种加密原语,允许用户在云存储服务器中搜索文件的同时确保原始文件的机密性.证书基可搜索加密在实现密文检索的基础上,解决了证书管理、密钥托管、安全信道等问题.然而,已有的证书基可搜索加密要么使用耗时的双线性映射操作,要么无法满足发送者匿名特性.同时其仅考虑单个接收者,致使多个接收者场景下效率低,不能满足现实需求.为解决上述不足,基于椭圆曲线密码学,利用密钥交换思想和数字签名技术,本文提出多接收者证书基可搜索加密方案.对于相同数据,方案中发送者仅仅执行一次加密,即可使得多个接收者能够同时进行搜索.同时,发送者使用自己的私钥和证书生成密文,导致敌手无法生成有效密文发动关键词猜测攻击,确保了搜索陷门的安全性.本文所提方案中搜索陷门仅由一个群元素组成,同时没有泄露发送者的身份信息实现了匿名性.安全性分析表明,在随机预言机模型中,基于计算性Diffie-Hellman假设,本文所提方案能够满足适应性选择关键词攻击的不可区分性和适应性关键词猜测攻击的不可区分性.性能分析表明,与相关方案相比,本文所提方案实现了低的计算代价和通信代价,更加适用于云存储环境下的多用户服务场景.

关键词：可搜索加密证书基密码学多接收者可证明安全云存储

Impacts of Ice-Ocean Stress on the Subpolar Southern Ocean:Role of the Ocean Surface Current

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Advances in Atmospheric Sciences 2024年第2期41卷 293-309页

作者： Yang WU zhaomin wang Chengyan LIU Liangjun YAN School of Information Engineering Nanjing Xiaozhuang UniversityNanjing 211171China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China College of Oceanography Hohai UniversityNanjing 210098China

The mechanical influences involved in the interaction between the Antarctic sea ice and ocean surface current(OSC)on the subpolar Southern Ocean have been systematically investigated for the first time by conducting two simulations that include and exclude the OSC in the calculation of the ice-ocean stress(IOS), using an eddy-permitting coupled ocean-sea ice global model. By comparing the results of these two experiments, significant increases of 5%, 27%, and 24%, were found in the subpolar Southern Ocean when excluding the OSC in the IOS calculation for the ocean surface stress,upwelling, and downwelling, respectively. Excluding the OSC in the IOS calculation also visibly strengthens the total mechanical energy input to the OSC by about 16%, and increases the eddy kinetic energy and mean kinetic energy by about38% and 12%, respectively. Moreover, the response of the meridional overturning circulation in the Southern Ocean yields respective increases of about 16% and 15% for the upper and lower branches;and the subpolar gyres are also found to considerably intensify, by about 12%, 11%, and 11% in the Weddell Gyre, the Ross Gyre, and the Australian-Antarctic Gyre, respectively. The strengthened ocean circulations and Ekman pumping result in a warmer sea surface temperature(SST), and hence an incremental surface heat loss. The increased sea ice drift and warm SST lead to an expansion of the sea ice area and a reduction of sea ice volume. These results emphasize the importance of OSCs in the air-sea-ice interactions on the global ocean circulations and the mass balance of Antarctic ice shelves, and this component may become more significant as the rapid change of Antarctic sea ice.

关键词： subpolar Southern Ocean Antarctic sea ice ice-ocean stress air-sea-ice-ocean interaction ocean surface current MITgcm-ECCO2

METTL7A-mediated m6A modification of corin reverses bisphosphonates-impaired osteogenic differentiation of orofacial BMSCs

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International Journal of Oral Science 2024年第3期16卷 528-538页

作者： Yizhou Jin Xiao Han Yuejun wang Zhipeng Fan Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction Beijing Stomatological HospitalSchool of StomatologyCapital Medical UniversityBeijingChina Beijing Laboratory of Oral Health Capital Medical UniversityBeijingChina Research Unit of Tooth Development and Regeneration Chinese Academy of Medical SciencesBeijingChina

Bisphosphonate-related osteonecrosis of jaw(BRONJ)is characterized by impaired osteogenic differentiation of orofacial bone marrow stromal cells(BMSCs).Corin has recently been demonstrated to act as a key regulator in bone development and orthopedic ***,the role of corin in BRONJ-related BMSCs dysfunction remains unclarified.A m6A epitranscriptomic microarray study from our group shows that the CORIN gene is significantly upregulated and m6A hypermethylated during orofacial BMSCs osteogenic *** knockdown inhibits BMSCs osteogenic differentiation,whereas corin overexpression or soluble corin(sCorin)exerts a promotion ***,corin expression is negatively regulated by bisphosphonates(BPs).Corin overexpression or sCorin reverses BPs-impaired BMSCs differentiation ***,we find altered expression of phos-ERK in corin knockdown/overexpression BMSCs and BMSCs under sCorin ***98059(a selective ERK inhibitor)blocks the corin-mediated promotion *** regard to the high methylation level of corin during osteogenic differentiation,we apply a non-selective m6A methylase inhibitor,Cycloleucine,which also blocks the corin-mediated promotion ***,we demonstrate that METTL7A modulates corin m6A modification and reverses BPs-impaired BMSCs function,indicating that METTL7A regulates corin expression and thus contributes to orofacial BMSCs differentiation *** conclude,our study reveals that corin reverses BPs-induced BMSCs dysfunction,and METTL7A-mediated corin m6A modification underlies corin promotion of osteogenic differentiation via the ERK *** hope this brings new insights into future clinical treatments for BRONJ.

关键词： impaired cor mediated

Amplified internal electric field of Cs_(2)CuBr_(4)@WO_(3-x)S-scheme heterojunction for efficient CO_(2)photoreduction

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Journal of Energy Chemistry 2024年第5期92卷 521-533页

作者： Zhijie Zhang Xuesheng wang Junyi Qian Jiayue Xu School of Materials Science and Engineering Shanghai Institute of TechnologyShanghai 201418China

Heterojunction construction,especially S-scheme heterojunction,represents an efficient universal strategy to achieve high-performance photocatalytic *** further performance stimulation of these well-designed heterojunctions,modulating the interfacial internal electric field(IEF)to steer dynamic charge transfer represents a promising ***,we realized the precise regulation of Fermi level(E_(F))of the oxidation semiconductor(mesoporous WO_(3-x))by tailoring the concentration of oxygen vacancies(V_(O)),maximizing the IEF intensity in Cs_(2)CuBr_(4)@WO_(3-x)(CCB@WO_(3-x))S-scheme *** augmented IEF affords a robust driving force for directional electron delivery,leading to boosted charge ***,the developed CCB@WO_(3-x)S-scheme heterojunction demonstrated outstanding photocatalytic CO_(2)reduction performance,with the electron consumption rate(Relectron)up to 390.34μmol g^(-1)h^(-1),which is 3.28 folds higher than that of pure *** in-depth analysis of the S-scheme electron transfer mode was presented via theoretical investigations,electron spin resonance(ESR),photo-irradiated Kelvin probe force microscopy(KPFM),and in-situ X-ray photoelectron spectroscopy(XPS).Finally,the CO_(2)photoconversion route was explored in detail using in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and DFT theoretical calculations.

关键词： Cs_(2)CuBr_(4) WO_(3-x) Oxygen vacancy S-scheme heterojunction Internal electricfield