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Dependable Deployment Method for Multiple Applications in Cloud Services Delivery Network 被引量:1
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作者 史佩昌 王怀民 +3 位作者 尹浩 丁博 刘雪宁 王淼 《China Communications》 SCIE CSCD 2011年第4期65-75,共11页
The mutual-interference phenomenon among multiple applications delivered as services through Cloud Services Delivery Network(CSDN)influences their QoS seriously.In order to deploy multiple applications dependably and ... The mutual-interference phenomenon among multiple applications delivered as services through Cloud Services Delivery Network(CSDN)influences their QoS seriously.In order to deploy multiple applications dependably and efficiently,we propose the Multiple Applications Co-Exist(MACE)method.MACE classifies multiple applications into different types and deploys them using isolation to some extent.Meanwhile,resource static allocation,dynamic supplement and resource reserved mechanism to minimize mutual-interference and maximize resource utilization are designed.After MACE is applied to a real large-scale CSDN and evaluated through 6-month measurement,we find that the CSDN load is more balanced,the bandwidth utilization increases by about 20%,the multiple applications'potential statistical multiplexing ratio decreases from 12% to 5%,and the number of complaint events affecting the dependability of CSDN services caused by multiple applications'mutual-interference has dropped to 0.Obviously,MACE offers a tradeoff and improvement for the dependability and efficiency goals of CSDN. 展开更多
关键词 cloud computing dependable deployment multiple applications co-exist content delivery networks
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Biochemical indicators for neuronal regeneration during intrathecal triamcinolone application in multiple sclerosis
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作者 Thomas Müller Sven Lütge 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第3期377-379,共3页
Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS). Essential charac- teristics are demyelination, inflammation and neurode- generation. This process affects the white an... Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS). Essential charac- teristics are demyelination, inflammation and neurode- generation. This process affects the white and grey matter in the CNS. MS patients experience various progression subtypes in association with the cerebral or spinal, acute inflammatory or glial sclerotic lesions (Mtiller, 2009). Most patients end up in a progressive, smouldering, chronic inflammatory process (MUller, 2009). Current predominantly used 1.5 respectively 3 Tesla MRI with Gadolinium~ application visualize the various old and acute lesions. They serve as a biological marker in com- bination with standardised assessment of brain atrophy, black holes, etc. However, MRI with a stronger magnetic 7 Tesla field with better sensitivity gave hints on an on- going, acute inflammatory, smouldering process even with Gadolinium~ enhancing acute lesions in the brain and the spinal cord in progressive, so-called relapse free MS patients (Mtiller, 2009; Sinnecker et al., 2012). Ad- ditionally, progress of MS is determined with subjective standardised clinical ratings (Sinnecker et al., 2012). Both methods are used for the evaluation of the efficacy of relapse rate reducing drugs. These compounds, i.e., in- terferons, teriflunamide, glatiramer acetate, fingolimod, fumarate or monoclonal antibodies, preponderantly weaken the malfunction of the peripheral immune system in relapse remitting MS patients. These MS drugs share one common disadvantage. They do not stop progression or improve MS within a framework of a regenerative process. They do not enable reversal of symptoms, for in- stance functional deficits or spasticity (Mtiller, 2009). 展开更多
关键词 RGMa Biochemical indicators for neuronal regeneration during intrathecal triamcinolone application in multiple sclerosis EDSS
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Multiple Antenna Technology and Its Application in WiMAX System
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作者 Zhao Qiong 1,2 Wang Yanwen 2 (1. School of Electronic Engineering of Xidian University,Xi’an 710071,China 2.Xi’an R&D Department of Mobile Research Institute, Corporation,Xi’an 710065,China) 《ZTE Communications》 2007年第3期32-35,共4页
Worldwide Interoperability for Microwave Access (WiMAX) technology has rapidly developed in recent years. It is becoming one of the hotspots among broadband wireless access technologies. A WiMAX system can provide ban... Worldwide Interoperability for Microwave Access (WiMAX) technology has rapidly developed in recent years. It is becoming one of the hotspots among broadband wireless access technologies. A WiMAX system can provide bandwidth efficiency higher than 2 bps/Hz. In order to improve coverage and reliability of the WiMAX system,the IEEE 802.16 standard supports multiple antenna techniques such as Alamouti Space-Time Coding (STC),Adaptive Antenna System (AAS) and Multiple Input Multiple Output (MIMO). The applications of the multiple antenna techniques improve system capacity and bandwidth efficiency significantly,and enhance the competence of the WiMAX technology greatly. 展开更多
关键词 WIMAX ACCESS MIMO multiple Antenna Technology and Its application in WiMAX System
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Application of Holistic Nursing in Patients with Multiple Rib Fracture and Hemopneumothorax
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作者 LI Yan 《外文科技期刊数据库(文摘版)医药卫生》 2021年第8期332-334,共5页
Objective: to analyze the effect of holistic nursing in the nursing of patients with multiple rib fractures and hemopneumothorax. Methods: taking the period from September 2019 to August 2020 as the research interval,... Objective: to analyze the effect of holistic nursing in the nursing of patients with multiple rib fractures and hemopneumothorax. Methods: taking the period from September 2019 to August 2020 as the research interval, 76 patients with multiple rib fractures and hemopneumothorax were randomly selected for research. On the basis of following the random number table method, they were divided into two groups, one group was the control group, receiving routine nursing, and the other group was the observation group, receiving overall nursing. The nursing effect, quality of life score and complications were compared between the two groups. Results: the nursing satisfaction score of the observation group was (86.58±3.21), which was higher than that of the control group (70.45±4.73), and the incidence of complications was lower than that of the control group. The data showed significant difference (P < 0.05). Conclusion: holistic nursing for patients with multiple rib fractures and hemopneumothorax can effectively reduce the probability of complications, accelerate the speed of bone healing and improve the quality of life of patients. It can be widely used in clinic. 展开更多
关键词 holistic nursing multiple rib fractures with hemopneumothorax PATIENT NURSING applicATION
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Analysis on the Practical Application of Multiple Incentive Mechanism in Educational Management
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作者 Yanjun Huang 《Journal of Contemporary Educational Research》 2021年第12期166-170,共5页
In the new era,China’s education industry was ushered in a high-quality development stage.On the one hand,it is necessary to set a goal of education management on the all-round development of students.On the other ha... In the new era,China’s education industry was ushered in a high-quality development stage.On the one hand,it is necessary to set a goal of education management on the all-round development of students.On the other hand,we should innovate some practical application schemes of diversified incentive mechanism consistent with the needs of educational management.Taking this as the starting point,this paper summarizes the connotation of incentive mechanism and diversified incentive mechanism,and analyzes the practical problems of single incentive standard,issues on incentive timeliness,and reduced participation of incentive objects at the current stage.On this basis,this paper puts forward some corresponding measures from three angles:opening up thinking,updating in time and emphasizing the target. 展开更多
关键词 Education management multiple incentive mechanism Practical application
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Multiple Intelligence Theory in Integrated English Teaching
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作者 杨丹 《科技信息》 2014年第13期265-265,共1页
Integrated English is a core course for English major students in our college,and this article mainly discusses the application of Multiple Intelligence theory in Integrated English classroom.
关键词 multiple INTELLIGENCE THEORY INTEGRATED ENGLISH AP
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A novel forced motion apparatus with potential applications in structural engineering 被引量:3
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作者 Lin ZHAO Xi XIE +5 位作者 Yan-yan ZHAN Wei CUI Yao-jun GE Zheng-chun XIA Sheng-qiao XU Min ZENG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2020年第7期593-608,共16页
This paper reviews the development of forced motion apparatuses(FMAs) and their applications in wind engineering. A kind of FMA has been developed to investigate nonlinear and nonstationary aerodynamic forces consider... This paper reviews the development of forced motion apparatuses(FMAs) and their applications in wind engineering. A kind of FMA has been developed to investigate nonlinear and nonstationary aerodynamic forces considering the coupled effects of multiple degrees of freedom(DOFs). This apparatus can make section models to vibrate in a prescribed displacement defined by a numerical signal in time domain, including stationary and nonstationary movements with time-variant amplitudes and frequencies and even stochastic displacements. A series of validation tests show that the apparatus can re-illustrate various motions with enough precision in 3 D coupled states of two linear displacements and one torsional displacement. To meet the requirement of aerodynamic modeling, the flutter derivatives of a box girder section are identified, verifying its accuracy and feasibility by comparing with previously reported results. By simulating the nonstationary vibration with time-variant amplitude, the phenomena of frequency multiplication and memory effects are examined. In addition to studying the aerodynamics of a bluff body under large amplitudes and nonstationary vibrations, some potential applications of the proposed FMA are discussed in vehicle-bridge-wind dynamic analysis, pile-soil interaction, and line-tower coupled vibration aerodynamics in structural engineering. 展开更多
关键词 Forced motion apparatus(FMA) Coupled vibration Stochastic vibration simulation Aerodynamic force Frequency multiplication Memory effects Wind engineering Potential applications
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Updating the coal quality parameters in multiple production benches based on combined material measurement: a full case study 被引量:2
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作者 Cansln Yiiksel Jorg Benndorf +1 位作者 Matthias Lindig Oliver Lohstrater 《International Journal of Coal Science & Technology》 EI 2017年第2期159-171,共13页
An efficient resource model updating framework concept was proposed aiming for the improvement of raw material quality control and process efficiency in any type of mining operation. The concept integrates sensor data... An efficient resource model updating framework concept was proposed aiming for the improvement of raw material quality control and process efficiency in any type of mining operation. The concept integrates sensor data measured online on the production line into the resource or grade/quality control model and continuously provides locally more accurate estimates. The concept has been applied in a lignite field with the aim of identifying local impurities in a coal seam and to improve the prediction of coal quality attributes in neighbouring blocks. A significant improvement was demonstrated which led to better coal quality management. So far, the proposed concept and the application in coal mining was limited to a case where online measurements were unambiguously trackable due to a single extraction face being the point of origin for the material. This contribution presents an extension to the case, where characteristics from blended material, originating from two or three simultaneously operating extraction faces, are measured. The challenge tackled in this contribution is the updating of local coal quality estimates in different production benches based on measurements of a blended material stream. For a practical application of the updating concept, which is based on the Ensemble Kalman Filter, a simple method for generating prior ensemble members based on block geometries defined in the short-term model and the variogram, is discussed. This method allows for a fast, semi-automated and rather simple generation of prior models instead of generating a fully simulated deposit model using conditional simulation in geostatistics. It should foster operational implementation in an industrial environment. The main purpose of this article is to investigate the applicability of the developed framework with a simplified prior resource model. In addition to this any model improvements due to the integration of sensor data obtained by observing a blend of coal from multiple extraction faces is investigated. 展开更多
关键词 Resource model updating Online sensor Ensemble Kalman filter multiple excavator LIGNITE Real application
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Multiple Regression and Big Data Analysis for Predictive Emission Monitoring Systems
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作者 Zinovi Krougly Vladimir Krougly Serge Bays 《Applied Mathematics》 2023年第5期386-410,共25页
Predictive Emission Monitoring Systems (PEMS) offer a cost-effective and environmentally friendly alternative to Continuous Emission Monitoring Systems (CEMS) for monitoring pollution from industrial sources. Multiple... Predictive Emission Monitoring Systems (PEMS) offer a cost-effective and environmentally friendly alternative to Continuous Emission Monitoring Systems (CEMS) for monitoring pollution from industrial sources. Multiple regression is one of the fundamental statistical techniques to describe the relationship between dependent and independent variables. This model can be effectively used to develop a PEMS, to estimate the amount of pollution emitted by industrial sources, where the fuel composition and other process-related parameters are available. It often makes them sufficient to predict the emission discharge with acceptable accuracy. In cases where PEMS are accepted as an alternative method to CEMS, which use gas analyzers, they can provide cost savings and substantial benefits for ongoing system support and maintenance. The described mathematical concept is based on the matrix algebra representation in multiple regression involving multiple precision arithmetic techniques. Challenging numerical examples for statistical big data analysis, are investigated. Numerical examples illustrate computational accuracy and efficiency of statistical analysis due to increasing the precision level. The programming language C++ is used for mathematical model implementation. The data for research and development, including the dependent fuel and independent NOx emissions data, were obtained from CEMS software installed on a petrochemical plant. 展开更多
关键词 Matrix Algebra in multiple Linear Regression Numerical Integration High Precision Computation applications in Predictive Emission Monitoring Systems
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考虑多种应用场景的锂离子电池多阶优化充电策略 被引量:2
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作者 段双明 夏馗峰 朱微 《储能科学与技术》 北大核心 2025年第2期779-790,共12页
锂离子电池因其良好的性能,广泛应用于电动汽车等领域中。具有良好充电性能的充电策略对于锂离子电池至关重要,且锂离子电池的充电方法一直制约着电动汽车的大规模应用。为此,本工作提出了一种考虑多种应用场景的锂离子电池优化充电策... 锂离子电池因其良好的性能,广泛应用于电动汽车等领域中。具有良好充电性能的充电策略对于锂离子电池至关重要,且锂离子电池的充电方法一直制约着电动汽车的大规模应用。为此,本工作提出了一种考虑多种应用场景的锂离子电池优化充电策略。首先建立了锂离子电池的电模型、热模型和老化模型用于模拟充电过程与采集数据,之后根据电池内阻变化曲线制定SMCC充电策略,建立关于充电速度和SOH衰减的目标函数并利用改进的蝙蝠算法对SMCC电流进行优化,得到不同加权系数下的优化充电策略。根据不同的电池应用场景,提出了利用帕累托前沿得到的均衡SMCC充电策略以及快速充电SMCC充电策略和提高循环次数SMCC策略。最后,将提出的三种优化充电策略与CC-CV策略进行比较分析,证明提出的优化充电策略能够更好地适应其对应的应用场景,并且能够缩短锂离子电池充电时间和减小SOH衰减。 展开更多
关键词 锂离子电池 多应用场景 SMCC策略 均衡充电策略
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融合全尺度特征与轨迹修正的遮挡车辆跟踪
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作者 郭俊锋 张子华 《北京航空航天大学学报》 北大核心 2025年第5期1608-1619,共12页
为改善车辆跟踪过程中因遮挡造成的跟踪漂移及身份切换(IDS)问题,在Deep SORT算法基础上提出一种融合全尺度特征与轨迹修正的遮挡车辆跟踪方法。引入全尺度特征提取网络提取目标不同尺度特征并实现自适应动态融合,增强目标表观特征。提... 为改善车辆跟踪过程中因遮挡造成的跟踪漂移及身份切换(IDS)问题,在Deep SORT算法基础上提出一种融合全尺度特征与轨迹修正的遮挡车辆跟踪方法。引入全尺度特征提取网络提取目标不同尺度特征并实现自适应动态融合,增强目标表观特征。提出一种轨迹修正算法对遮挡过程中的跟踪轨迹进行修复,重新更新Kalman滤波参数以减小遮挡过程中累积的线性误差,优化目标运动特征。结合外观特征和运动特征实现遮挡车辆跟踪。通过消融实验与可视化分析验证所提方法的可行性,在KITTI数据集上的实验结果表明:与现有典型方法相比,所提方法取得最高综合得分为78.13%和最低的IDS次数为192,有效改善遮挡车辆跟踪中的IDS问题,提高车辆跟踪鲁棒性。 展开更多
关键词 计算机应用 多目标跟踪 车辆跟踪 全尺度 轨迹修正
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基于POA的高职英语课程教学设计探索与实践——以湖北城市建设职业技术学院为例
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作者 刘芳 黄宁 《湖北工业职业技术学院学报》 2025年第5期80-84,共5页
产出导向法(POA)是契合我国高职外语教学实际的本土化理论,其“学习中心、学用一体、关键能力”理念可有效解决传统高职英语“学用脱节”“职业适配性不足”的问题。本文分析POA与高职英语课程设计的融合理据后,创新构建“课前(目标确定... 产出导向法(POA)是契合我国高职外语教学实际的本土化理论,其“学习中心、学用一体、关键能力”理念可有效解决传统高职英语“学用脱节”“职业适配性不足”的问题。本文分析POA与高职英语课程设计的融合理据后,创新构建“课前(目标确定-任务设计)、课中(情景驱动-活动促成)、课后(评价促学)”的三阶五步框架,以“职场实习生英文推荐信撰写”为案例阐述实施路径。经能力测试、满意度调研和企业HR评价验证,该设计能显著提升学生职场英语应用能力,为高职英语从“知识传授”向“职业能力培养”转型提供可复制方案,也丰富了POA在职业教育领域的应用研究。 展开更多
关键词 产出导向法(POA) 高职英语 课程设计 职场语言应用 多元评价
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基于AHP-BCO-GRA的多场景风火氢储三层容量优化配置方法
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作者 韩晓娟 杨小烟 +1 位作者 李昊宇 郭思琪 《太阳能学报》 北大核心 2025年第11期509-520,共12页
针对高比例新能源并网导致电网波动和调峰能力不足等问题,提出基于层次分析(AHP)-边境牧羊犬搜索算法(BCO)-灰色关联度分析法(GRA)的多场景风火氢储多能互补系统三层容量优化配置方法。采用改进完全自适应噪声集合经验模态分解(ICEEMDAN... 针对高比例新能源并网导致电网波动和调峰能力不足等问题,提出基于层次分析(AHP)-边境牧羊犬搜索算法(BCO)-灰色关联度分析法(GRA)的多场景风火氢储多能互补系统三层容量优化配置方法。采用改进完全自适应噪声集合经验模态分解(ICEEMDAN)对风电输出功率进行分解,自适应调整磷酸铁锂电池、碱性电解槽和质子交换膜电解槽之间的容量划分;综合考虑火电机组的经济性、环保性和可靠性,利用AHP确定火电机组最优容量;以多能互补系统成本最低为目标,建立基于BCO的储能系统最优容量配置模型。从电-氢耦合系统安全角度出发,利用GRA验证电-氢耦合系统容量配置结果的合理性。通过中国某电站实际运行数据验证了该文方法的有效性,仿真结果表明,由该文方法得到的10 min并网波动率最低15.58%,辅助火电机组深度调峰深度由30.00%下降至24.99%。 展开更多
关键词 多能互补系统 电氢耦合储能 三层优化 多应用场景 容量配置
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多源流理论视域下一流应用型本科高校建设政策过程考察——基于江苏实践的分析
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作者 吴立保 程一鸣 《中部高教研究》 2025年第2期33-39,共7页
多源流理论旨在从问题源流、政策源流和政治源流出发,对公共政策过程进行剖析,解读其动态演化规律。基于金登的多源流理论,分析解构江苏省一流应用型本科高校建设的政策过程,其中,区域经济特色发展的原生需求、“双一流”建设政策的辐... 多源流理论旨在从问题源流、政策源流和政治源流出发,对公共政策过程进行剖析,解读其动态演化规律。基于金登的多源流理论,分析解构江苏省一流应用型本科高校建设的政策过程,其中,区域经济特色发展的原生需求、“双一流”建设政策的辐射作用以及应用型本科高校财政投入的现实基数构成“问题源流”,政策共同体的联合、应用型本科高校建设实现可行性的标准构成“政策源流”,民众情绪态势、利益集团之间压力构成“政治源流”。继而,作为“政策之窗”的“江苏省高等教育学会应用型本科院校研究会成立大会暨一流应用型本科院校建设研讨会”的顺利召开成为发展号角,三流汇集形成共振,开启“机会之窗”,推动政策和实践形成有效衔接。 展开更多
关键词 多源流理论 应用型本科 政策过程
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华南早晚季不同施氮水平下影响籼稻米食味的品质性状
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作者 张兰兰 刘迪林 +9 位作者 马晓智 霍兴 孔乐 李金华 付崇允 廖亦龙 朱满山 曾学勤 柳武革 王丰 《中国水稻科学》 北大核心 2025年第6期832-846,共15页
【目的】食味是决定稻米品质的最关键因子,但是稻米食味品质不仅取决于品种自身遗传背景,而且还受施肥和种植季节等环境因素影响。在不同种植季节和不同施氮水平下全面探讨稻米外观、加工、蒸煮营养等品质性状与食味之间的关系,可为培... 【目的】食味是决定稻米品质的最关键因子,但是稻米食味品质不仅取决于品种自身遗传背景,而且还受施肥和种植季节等环境因素影响。在不同种植季节和不同施氮水平下全面探讨稻米外观、加工、蒸煮营养等品质性状与食味之间的关系,可为培育不同种植条件下均能稳定表现优良食味的水稻新品种具有重要的参考意义。【方法】2021年以17个华南不同类型水稻品种(系)为供试材料,在广州早、晚两季各设置施氮量为0 kg/hm^(2)(N0)、90 kg/hm^(2)(N1)、135 kg/hm^(2)(N2)和180 kg/hm^(2)(N3)等4种不同处理,通过三因素方差分析、逐步多元回归分析和通径分析,系统探讨稻米外观、加工、蒸煮与营养等品质性状与食味之间的关系。【结果】1)垩白米率(CGR)、垩白度(CD)、胶稠度(GC)和蛋白质(PC)同时受季节、施氮量、品种、季节×施氮水平互作效应、季节×品种互作效应和季节×氮水平×品种三因素互作效应等7种因素影响,是最不稳定的性状;碱消值(ASV)则仅受季节和品种两因素的显著影响,属于最为稳定的性状;糙米率(BRR)、精米率(MRR)、米粒长宽比(LWR)、透明度(TR)和直链淀粉含量(AC)等5个均为中等不稳定性状。2)早、晚两季不同施氮处理共检测到显著影响米饭食味(TV)的品质性状11个。其中,AC和PC在早季、晚季都能重复检测到,且对TV均起负向调控作用;MRR、CGR、CD、TR和GC在晚季中重复检测到;BRR、整精米率(HRR)和ASV仅在晚季N0中检测到。3)对TV有显著影响的11个品质性状中,仅GC和LWR的直接通径系数和总体效应均为正值,即对TV起正向的调控作用;ASV和BRR尽管对TV的直接通径系数为正值,但总体效应为负值,即对TV总体起负向调控作用;其他7个性状均为TV的负向调控因子。【结论】根据这些品质性状对TV的作用大小与方向,培育高食味优质籼稻新品种应该同时具有的品质性状目标:LWR≥3.5、HRR≥58%、TR=1级、CGR≤10%、CD≤1%、AC=13%~17%、ASV≥6.0级、GC≥60 mm和精米PC≤6.4%等。 展开更多
关键词 籼稻 品质性状 食味 施氮量 种植季节 逐步多元回归 通径分析
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塞利尼索在复发难治性多发性骨髓瘤治疗中的应用进展 被引量:1
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作者 童煜歆 谭亚敏 《中国实验血液学杂志》 北大核心 2025年第4期1233-1236,共4页
多发性骨髓瘤(MM)是一种常见且难治的恶性血液肿瘤,目前尚无根治方法,且易复发。复发/难治性骨髓瘤(RRMM)患者往往在前期已接受包括蛋白酶体抑制剂(PI)和/或免疫调节药物(IMiD)在内的多种药物治疗。因此,对于这类患者,治疗的主要目标是... 多发性骨髓瘤(MM)是一种常见且难治的恶性血液肿瘤,目前尚无根治方法,且易复发。复发/难治性骨髓瘤(RRMM)患者往往在前期已接受包括蛋白酶体抑制剂(PI)和/或免疫调节药物(IMiD)在内的多种药物治疗。因此,对于这类患者,治疗的主要目标是在可接受的毒性和维持生活质量的前提下实现疾病的控制。本文结合国内外相关研究报道,旨在综述塞利尼索治疗RRMM患者的临床应用效果。塞利尼索作为新型的治疗RRMM的主要手段,其药理机制独特,能进一步提高RRMM患者的临床缓解率,并改善患者的生存质量。虽然塞利尼索在使用过程中会造成一系列不良反应,但临床进行针对性治疗后,不良反应大多可缓解或消失,采取有效的预防措施也能最大限度减少不良反应的发生。总之,塞利尼索在RRMM患者中展现出了广阔的应用前景,未来将进行更加深入的研究以优化塞利尼索的治疗方案,从而使更多的RRMM患者从中获益。 展开更多
关键词 塞利尼索 复发难治性多发性骨髓瘤 应用进展 不良反应
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不同施磷量对麦后复种蔬菜土壤理化性状的影响
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作者 吴炫燕 刘根红 +4 位作者 马辉 刘露露 李杨 孙大智 陈璐 《西南农业学报》 北大核心 2025年第2期360-374,共15页
【目的】探究不同施磷量下,宁夏引黄灌区春小麦收割后复种果菜类蔬菜辣椒、叶菜类蔬菜娃娃菜以及根菜类蔬菜萝卜对土壤理化性状的影响,以确定麦后复种蔬菜作物适宜施磷量。【方法】采用两因素裂区试验设计,主区为3种不同复种蔬菜作物,... 【目的】探究不同施磷量下,宁夏引黄灌区春小麦收割后复种果菜类蔬菜辣椒、叶菜类蔬菜娃娃菜以及根菜类蔬菜萝卜对土壤理化性状的影响,以确定麦后复种蔬菜作物适宜施磷量。【方法】采用两因素裂区试验设计,主区为3种不同复种蔬菜作物,娃娃菜、辣椒和萝卜,副区为不同施磷量梯度,设置4个施磷水平:P_(1)(0)、P_(2)(60 kg/hm^(2))、P_(3)(120 kg/hm^(2))和P_(4)(180 kg/hm^(2)),在作物生长期间定期对土壤0~20、20~40 cm剖面主要酶活性和土壤理化性状指标进行测定。【结果】麦后复种不同类型蔬菜的土壤磷酸酶活性在P_(3)达到最大,土壤过氧化氢酶活性在P_(1)最大,随着施磷量的增加,过氧化氢酶活性呈下降趋势;土壤碱性磷酸酶活性呈先升后降趋势。土壤中各个理化性质的指标表现出不同的变化。相同施磷量条件下,不同种类蔬菜的电导率、速效钾有不同变化,电导率表现为辣椒>娃娃菜>萝卜;随施磷量增加,速效钾含量呈先增后降趋势,速效钾变化趋势为辣椒>娃娃菜>萝卜。全氮、速效磷、全磷、碱解氮、有机质随施磷量的增加呈上升趋势,并在P_(3)达到最大。随施磷量增加,3种蔬菜产量较未施磷时升高;地力贡献率在P_(2)处理达到最大。麦后复种辣椒对土壤理化性质的影响最大。【结论】适宜的施磷量能改善土壤理化性质,促进蔬菜生长,提高产量和品质。当施磷量为120 kg/hm^(2)时,辣椒和萝卜产量最大,当施磷量为180 kg/hm^(2)时,娃娃菜产量最大。 展开更多
关键词 施磷量 复种 蔬菜 土壤理化性状
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新时期联合基金项目统筹管理优化研究——基于多元主体交互网络分析的视角
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作者 汪琛 武晨箫 李正风 《中国科技论坛》 北大核心 2025年第7期36-44,共9页
新时期国家自然科学基金联合基金是一类具有中国特色的基础研究资助项目,其本质是一种多主体协同的高效能合作投资模式。然而,随着改革的不断深入,新时期联合基金的统筹管理面临着一系列新的挑战。本文构建了新时期联合基金统筹管理的... 新时期国家自然科学基金联合基金是一类具有中国特色的基础研究资助项目,其本质是一种多主体协同的高效能合作投资模式。然而,随着改革的不断深入,新时期联合基金的统筹管理面临着一系列新的挑战。本文构建了新时期联合基金统筹管理的多元主体交互网络模型,指出新时期联合基金的统筹管理问题主要包括三个层面:一是国家自然科学基金委员会(NSFC)与联合资助方、科研团队三方交互过程中存在项目指南制定缺乏统筹、对共性问题和不同研究力量统筹不足等问题;二是NSFC与联合资助方之间存在联合资助方话语权弱、成果转化效率低、权责分配不清等困境;三是NSFC内部存在不同类型基金项目功能定位重叠、联合基金评审效率低且联合基金管理处与科学部工作对接不畅等挑战。为此,建议从以下几方面着手改进:加强联合基金的顶层设计与规划,协同多元主体的价值目标;增强联合资助方话语权,保障多元主体的合理利益诉求;深化联合基金管理机制改革,提升NSFC的组织服务能力等。 展开更多
关键词 联合基金 国家自然科学基金 应用型基础研究 统筹管理 多元主体交互网络分析
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考虑不同场景与利益主体的储能技术选型综合评价
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作者 沈昊天 张华良 +4 位作者 徐玉杰 苏旭 门静婧 王尧 陈海生 《能源研究与管理》 2025年第2期156-165,共10页
储能技术是新型电力系统中的关键核心要素,为了分析各类场景下储能的价值并选取适宜的储能技术,构建了有关储能的8类技术经济性客观评估指标体系,并通过分析储能项目的主体利益方,建立了涵盖政府、电网、运营商以及用户的4类多主体利益... 储能技术是新型电力系统中的关键核心要素,为了分析各类场景下储能的价值并选取适宜的储能技术,构建了有关储能的8类技术经济性客观评估指标体系,并通过分析储能项目的主体利益方,建立了涵盖政府、电网、运营商以及用户的4类多主体利益驱动的主观评估指标体系。基于发电侧、电网侧以及用户侧3类典型场景的储能技术需求,利用熵权法和层次分析法结合的组合赋权法开展综合评估分析,得到不同场景下最优储能技术选型方案。结果表明:在发电侧新能源消纳应用场景,抽水蓄能以及压缩空气储能等长时储能技术占有优势;在电网侧调频应用场景,拥有高功率密度和高频次充放电能力的飞轮储能技术评分最高;在用户侧场景下,装机规模灵活、成本可控以及具备高转换效率的电化学储能最优。 展开更多
关键词 储能 选型 应用场景 多利益主体 组合赋权
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慢性阻塞性肺疾病共病肺癌筛查工具分析
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作者 徐百川 王艳 +3 位作者 张彭 李艺婷 刘飞来 谢洋 《中国全科医学》 北大核心 2025年第30期3847-3852,3860,共7页
慢性阻塞性肺疾病(COPD)和肺癌(LC)是呼吸系统高发病率、高致死率的疾病,COPD是LC的独立高危因素,二者相互影响,给临床诊疗带来挑战。早发现、早治疗是提高预后的关键,因此前期筛查十分重要。本文从COPD-LC的研究现状出发,全面介绍了现... 慢性阻塞性肺疾病(COPD)和肺癌(LC)是呼吸系统高发病率、高致死率的疾病,COPD是LC的独立高危因素,二者相互影响,给临床诊疗带来挑战。早发现、早治疗是提高预后的关键,因此前期筛查十分重要。本文从COPD-LC的研究现状出发,全面介绍了现有的筛查工具情况,包括低剂量计算机断层扫描(LDCT)、COPD-LC筛查(LUCSS)评分及其改进版COPD-LUCSS-肺一氧化碳弥散量(DLCO)评分,以及其他COPD-LC风险预测模型等。通过客观分析现有筛查工具的优势与不足,提出开发新筛查工具的对策及注意事项,并展望了未来的应用前景,以期为未来COPD-LC的筛查研究提供助力。 展开更多
关键词 肺疾病 慢性阻塞性 肺肿瘤 慢性病共病 筛查工具 危险因素 预测模型 临床应用
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