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Inter-Regional Tech Complementarity:A Mechanism for Balanced Development and GVC Upgrading
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作者 Zheng Jianghuai Jin Shengnan 《China Economist》 2026年第1期2-32,共31页
In the complex architecture of global value-chain(GVC)trade,firms’technological content increasingly reflects external knowledge flows.This study examines how inter-regional technological complementarity shapes firms... In the complex architecture of global value-chain(GVC)trade,firms’technological content increasingly reflects external knowledge flows.This study examines how inter-regional technological complementarity shapes firms’GVC advancement,measured by the domestic value-added rate(DVAR)in exports.Using integrated Chinese microdata(2000-2014),we find this complementarity significantly boosts export DVAR,explaining about one-quarter of its observed growth.Two mechanisms drive this effect:increased use of domestic intermediates and gains in firm productivity.The benefits are especially large for firms with lower human capital and for those in accessible,innovation-peripheral regions,helping narrow productivity gaps across firms and space.Affected firms also exhibit broader export scopes,higher product quality,more diversified destinations,and greater markups-firm-level evidence of GVC upgrading.These findings highlight how external technological linkages drive upgrading and underscore the importance of fostering inter-regional synergies for balanced development. 展开更多
关键词 technological complementarity global value chains domestic value-added rate(DVAR) balanced regional development
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Fluid therapy in acute pancreatitis comparing balanced solutions and normal saline:A systematic review,meta-analysis and trial sequential analysis 被引量:1
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作者 Lin Gao Hsiang-Wei Wang +4 位作者 Zi-Rui Liu Yi-Zhen Xu Lu Ke Wei-Qin Li John A Windsor 《Hepatobiliary & Pancreatic Diseases International》 2025年第4期371-380,共10页
Background:Isotonic crystalloids are recommended as the first choice for fluid therapy in acute pan-creatitis(AP),with normal saline(NS)and lactate Ringer’s(LR)used most often.Evidence based recom-mendations on the t... Background:Isotonic crystalloids are recommended as the first choice for fluid therapy in acute pan-creatitis(AP),with normal saline(NS)and lactate Ringer’s(LR)used most often.Evidence based recom-mendations on the type of fluid are conflicting and generally come from small single-center randomized controlled trials(RCTs).We therefore conducted a systematic review and meta-analysis to compare the effect of balanced solutions(BS)versus NS on patient-centered clinical outcomes in AP.Methods:From four databases searched up to October 2024,we included only RCTs of adult patients with AP that compared the use of BS(including LR,acetate Ringer’s,etc.)with NS.The primary out-come was the disease advances from AP to moderately severe and severe AP(MSAP/SAP).Trial sequential analyses(TSA)were conducted to control for type-I and type-II errors and Grading of Recommendations Assessment,Development,and Evaluation(GRADE)was used to assess the quality of evidence.Results:Six RCTs were identified and included,involving 260 patients treated with BS and 298 patients with NS.Patients who received the BS had less MSAP/SAP[odds ratio(OR)=0.50,95%confidence in-terval(CI):0.29 to 0.85,P=0.01,I^(2)=0%;5 studies,299 patients],reduced the need of ICU admission(OR=0.60,95%CI:0.39 to 0.93,P=0.02,I^(2)=0%;5 studies,507 patients)and shorter length of hospital stay[mean difference(MD)=-0.88,95%CI:-1.48 to-0.28,P=0.004,I^(2)=0%;6 studies,558 patients;confirmed by TSA with high certainty]compared with those who received NS.The evidence for most of the clinical outcomes was rated as moderate to low due to the risk of bias,imprecision and inconsistency.Conclusions:BS,compared with NS,was associated with improved clinical outcomes in patients with AP.However,given the moderate to low quality of evidence for most of the outcomes assessed,further trials are warranted. 展开更多
关键词 Acute pancreatitis Fluid therapy Normal saline balanced solution Systematic review
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A novel optimization scheme for structure and balance of compound balanced beam pumping units using the PSO, GA, and GWO algorithms
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作者 Jie Wang Quan-Ying Guo +3 位作者 Cheng-Long Fu Gang Dai Cheng-Yu Xia Li-Qin Qian 《Petroleum Science》 2025年第3期1340-1359,共20页
The beam pumping unit(BPU)remains the most stable and reliable equipment for crude oil lifting.Despite its simple four-link mechanism,the structural design of the BPU presents a constrained single-objective optimizati... The beam pumping unit(BPU)remains the most stable and reliable equipment for crude oil lifting.Despite its simple four-link mechanism,the structural design of the BPU presents a constrained single-objective optimization problem.Currently,a comprehensive framework for the structural design and optimization of compound balanced BPUs is lacking.Therefore,this study proposes a novel structural design scheme for BPUs,aiming to meet the practical needs of designers and operators by sequentially optimizing both the dynamic characteristics and balance properties of the BPUs.A dynamic model of compound balanced BPU was established based on D'Alembert's principle.The constraints for structural dimensions were formulated based on the actual operational requirements and design experience with BPUs.To optimize the structure,three algorithms were employed:the particle swarm optimization(PSO)algorithm,the genetic algorithm(GA),and the gray wolf optimization(GWO)algorithm.Each newly generated individuals are regulated by constraints to ensure the rationality of the outcomes.Furthermore,the integration of three algorithms ensures the increased likelihood of attaining the global optimal solution.The polished rod acceleration of the optimized structure is significantly reduced,and the dynamic characteristics of the up and down strokes are essentially symmetrical.Additionally,these three algorithms are also applied to the balance optimization of BPUs based on the measured dynamometer card.The calculation results demonstrate that the GWO-based optimization method exhibits excellent robustness in terms of structural optimization by enhancing the operational smoothness of the BPU,as well as in balance optimization by achieving energy conservation.By applying the optimization scheme proposed in this paper,the CYJW7-3-23HF type of BPU was designed,achieving a maximum polished rod acceleration of±0.675 m/s^(2) when operating at a stroke of 6 min^(−1).When deployed in two wells,the root-mean-square(RMS)torque was minimized,reaching values of 7.539 kN·m and 12.921 kN·m,respectively.The proposed design method not only contributes to the personalized customization but also improves the design efficiency of compound balanced BPUs. 展开更多
关键词 Compound balanced BPU Dynamic model Structural optimization Balance optimization CONSTRAINTS
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High-Order Common-Mode and Differential-Mode Reflectionless Balanced Bandpass Filters with Improved Selectivity and Out-of-Band Rejection
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作者 Zhang Yifan Wu Yongle +2 位作者 Wang Weimin Xu Ruoxi Cai Yuanlong 《China Communications》 2025年第8期87-101,共15页
High-selectivity common-mode(CM)and differential-mode(DM)reflectionless balanced bandpass filters(BBPFs)are proposed in this article.By loading absorption networks at single/both ends of the basic ring resonator,input... High-selectivity common-mode(CM)and differential-mode(DM)reflectionless balanced bandpass filters(BBPFs)are proposed in this article.By loading absorption networks at single/both ends of the basic ring resonator,input-/two-port wideband CM and DM reflectionless performance,wideband filtering performance and all-stop CM suppression are obtained.The absorption network composed of K-sections of coupled-lines(CLs)terminated with grounded resistors can not only extend the filtering performance to high order,but also realize wideband absorption of CM noise and out-of-band DM signals.Absorptive stubs are loaded at ports to increase the design flexibility and enhance the absorption.As for the input-reflectionless type,multiple independently controlled transmission zeros(TZs)are obtained by the TZ control network to improves the selectivity and out-of-band rejection.A set of 2 GHz micro-strip BBPFs are designed and measured,which shows simultaneous CM and DM absorption performance. 展开更多
关键词 balanced filter grounded resistors highorder high-selectivity reflectionless filter ring resonator
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A dynamic load-balanced scheme based on flow classification for software-defined data center
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作者 YU Yang JING Zhengjun +1 位作者 CHEN Qianmin WANG Xiumei 《High Technology Letters》 2025年第4期338-346,共9页
Aiming at the problems such as low throughput and unbalanced load of data center network caused by traditional multipath routing strategy,a dynamic load balancing strategy for flow classification oriented to Fat-Tree ... Aiming at the problems such as low throughput and unbalanced load of data center network caused by traditional multipath routing strategy,a dynamic load balancing strategy for flow classification oriented to Fat-Tree topology based on the software defined network(SDN)architecture is proposed,named DLB-FC.Multi-index evaluation methods such as link state information and network traffic characteristics are considered.DLB-FC mechanism can dynamically adjust the flow classification threshold to differentiate between large and small flows.The scheme selects different forwarding paths to meet the transmission performance requirements of different flow characteristics.On this basis,an SDN simulation platform is built for performance testing.The simulation results show that DLB-FC algorithm can dynamically distinguish large flows from small flows and achieve load balancing effectively.Compared with equal-cost multi-path(ECMP),global first fit(GFF)and minmum total delay load routing(MTDLR)algorithms,DLB-FC scheme improves the network throughput and link utilization of the data center network effectively.The transmission delay is also reduced with better load balance. 展开更多
关键词 data center software defined network load balance multi-index evaluation Fat-Tree
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Narrowing Regional Gaps:A Study on the Strategies for Balanced Development of Regional Education in China
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作者 Siqi Wang Yuanyuan Jia +3 位作者 Geman Gao Chang Tian Feng Yu Yu Cai 《Journal of Contemporary Educational Research》 2025年第10期37-41,共5页
By comprehensively analyzing the current status of education development and the achievements of economic development in China,this paper reveals the synergistic effect between the overall improvement of education lev... By comprehensively analyzing the current status of education development and the achievements of economic development in China,this paper reveals the synergistic effect between the overall improvement of education levels and economic growth.The paper points out that although the increase in educational investment has provided talent support for economic development,the imbalance in regional education development still exists.Furthermore,the paper explores the two-way promotion mechanism between education and economic development,and proposes a series of strategies,including balanced layout,targeted support,and innovation-driven development,to achieve the coordinated and balanced development of regional education and narrow regional gaps.These strategies aim to optimize the allocation of educational resources,improve the quality of education,and promote the all-round progress of the economy and society. 展开更多
关键词 Regional gaps Regional education Coordinated and balanced development
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Prenatal diagnosis of balanced translocation from three families:Six case reports
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作者 Xun Kan Yu-Xin Xie +6 位作者 Lan Yao Lu-Yao Wang Yu-Xin Xia Jian-Qiao Sun Ming-Lei Bian Liang Yu Ying-Li Lu 《World Journal of Clinical Cases》 2025年第20期35-41,共7页
BACKGROUND Carriers of chromosomal balanced translocations are often physically healthy with no obvious developmental problems.However,potential chromosomal imbalance in their gametes can lead to implantation failure,... BACKGROUND Carriers of chromosomal balanced translocations are often physically healthy with no obvious developmental problems.However,potential chromosomal imbalance in their gametes can lead to implantation failure,miscarriage,or the birth of a child with a chromosomal abnormality.CASE SUMMARY We report six cases of chromosomal translocations involving three families,including the specific Robertson(Roche)translocation.Case 1:The karyotype of the proband was 46,XX,t(18;19)(q22;p12).Case 2:Interventional prenatal diagnosis at 18 weeks of gestation confirmed that the karyotype of the fetus was 46,XY,t(18;19)(q22;p12).Case 3:The karyotype of the proband was 46,XY,t(5;18)(p13;p11).Case 4:Interventional prenatal diagnosis at 14+6 weeks confirmed that the karyotype of the fetus was 46,XX,der(18)t(5;18)(p13;p11)pat.Case 5:The karyotype of the proband was 45,XY,der(14;22)(q10;q10).Case 6:Interventional prenatal diagnosis at 19+4 weeks confirmed that the karyotype of the fetus was 45,XX,rob(14;22)(q10;q10).CONCLUSION Carriers of chromosomal translocations have a high risk of adverse pregnancy outcomes,though they can still have normal offspring.This report on six cases of chromosomal translocations from three families could serve as a reference for future prenatal diagnosis of chromosomal translocations and decision-making on whether to continue the pregnancy. 展开更多
关键词 Chromosomal translocation Prenatal diagnosis balanced translocation Robertson translocation Case report
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Effect of amino acid-balanced diet-based nutritional-psychological intervention on muscle wasting and quality of life in cirrhosis patients
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作者 Wei-Wei Zhuge Lin-Xiu Zheng +2 位作者 Li-Juan Xu Si-Fang Zhou Hai-Xin Yao 《World Journal of Psychiatry》 2025年第11期231-239,共9页
BACKGROUND Patients with liver cirrhosis often experience muscle wasting that significantly affects their quality of life.AIM To investigate the effects of comprehensive nutritional and psychological interventions bas... BACKGROUND Patients with liver cirrhosis often experience muscle wasting that significantly affects their quality of life.AIM To investigate the effects of comprehensive nutritional and psychological interventions based on an amino acid-balanced diet on muscle wasting and quality of life in patients with liver cirrhosis.METHODS A retrospective study of 130 patients with liver cirrhosis(May 2023 to June 2024)was divided into control(conventional treatment,n=65)and observational groups(conventional+amino acid-balanced nutrition and psychological intervention,n=65).Anxiety(Self-Rating Anxiety Scale),depression(Self-Rating Depression Scale),lower limb muscle strength,and quality of life(Chronic Liver Disease Questionnaire)were assessed pre-intervention,and 3/6 months postintervention.RESULTS At baseline,no significant differences were observed between the two groups in terms of age,sex,etiology of cirrhosis,disease duration,disease severity,or any other measured outcome(P>0.05).At 3 months and 6 months post-intervention,the observational group exhibited significantly lower Self-Rating Anxiety Scale and Self-Rating Depression Scale scores than the control group(P<0.05),indicating reduced anxiety and depression as well as higher grip strength and increased lower limb muscle strength(P<0.05).Additionally,the observational group demonstrated superior Chronic Liver Disease Questionnaire scores across all domains, reflecting an improved quality of life (P < 0.05).CONCLUSIONAn amino acid-balanced diet and psychological intervention can effectively alleviate anxiety and depression andimprove muscle strength and quality of life in patients with cirrhosis and are worthy of clinical promotion. 展开更多
关键词 CIRRHOSIS SARCOPENIA Amino acid balanced diet Nutritional psychological intervention Quality of life
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Balanced Optimization of Dimensional Accuracy and Printing Efficiency in FDM Based on Data-Driven Modeling
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作者 Liu Changhui Li Hao +5 位作者 Yu Chunlong Liao Xueru Liu Xiaojia Sun Jianzhi Tang Qirong Yu Min 《Additive Manufacturing Frontiers》 2025年第2期97-110,共14页
Additive manufacturing(AM),particularly fused deposition modeling(FDM),has emerged as a transformative technology in modern manufacturing processes.The dimensional accuracy of FDM-printed parts is crucial for ensuring... Additive manufacturing(AM),particularly fused deposition modeling(FDM),has emerged as a transformative technology in modern manufacturing processes.The dimensional accuracy of FDM-printed parts is crucial for ensuring their functional integrity and performance.To achieve sustainable manufacturing in FDM,it is necessary to optimize the print quality and time efficiency concurrently.However,owing to the complex interactions of printing parameters,achieving a balanced optimization of both remains challenging.This study examines four key factors affecting dimensional accuracy and print time:printing speed,layer thickness,nozzle temperature,and bed temperature.Fifty parameter sets were generated using enhanced Latin hypercube sampling.A whale optimization algorithm(WOA)-enhanced support vector regression(SVR)model was developed to predict dimen-sional errors and print time effectively,with non-dominated sorting genetic algorithm Ⅲ(NSGA-Ⅲ)utilized for multi-objective optimization.The technique for Order Preference by Similarity to Ideal Solution(TOPSIS)was applied to select a balanced solution from the Pareto front.In experimental validation,the parts printed using the optimized parameters exhibited excellent dimensional accuracy and printing efficiency.This study comprehensively considered optimizing the printing time and size to meet quality requirements while achieving higher printing efficiency and aiding in the realization of sustainable manufacturing in the field of AM.In addition,the printing of a specific prosthetic component was used as a case study,highlighting the high demands on both dimensional precision and printing efficiency.The optimized process parameters required significantly less printing time,while satisfying the dimensional accuracy requirements.This study provides valuable insights for achieving sustainable AM using FDM. 展开更多
关键词 Fused deposition modeling Dimensional accuracy Process parameters Printing efficiency balanced optimization Sustainable manufacturing
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Digital twin-based structural health monitoring and measurements of dynamic characteristics in balanced cantilever bridge
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作者 Tidarut Jirawattanasomkul Le Hang +4 位作者 Supasit Srivaranun Suched Likitlersuang Pitcha Jongvivatsakul Wanchai Yodsudjai Punchet Thammarak 《Resilient Cities and Structures》 2025年第3期48-66,共19页
This study developed a digital twin(DT)and structural health monitoring(SHM)system for a balanced cantilever bridge,utilizing advanced measurement techniques to enhance accuracy.Vibration and dynamic strain measuremen... This study developed a digital twin(DT)and structural health monitoring(SHM)system for a balanced cantilever bridge,utilizing advanced measurement techniques to enhance accuracy.Vibration and dynamic strain measurements were obtained using accelerometers and piezo-resistive strain gauges,capturing low-magnitude dynamic strains during operational vibrations.3D-LiDAR scanning and Ultrasonic Pulse Velocity(UPV)tests captured the bridge's as-is geometry and modulus of elasticity.The resulting detailed 3D point cloud model revealed the structure's true state and highlighted discrepancies between the as-designed and as-built conditions.Dynamic properties,including modal frequencies and shapes,were extracted from the strain and acceleration measurements,providing critical insights into the bridge's structural behavior.The neutral axis depth,indicating stress distribution and potential damage,was accurately determined.Good agreement between vibration measurement data and the as-is model results validated the reliability of the digital twin model.Dynamic strain patterns and neutral axis parameters showed strong correlation with model predictions,serving as sensitive indicators of local damage.The baseline digital twin model and measurement results establish a foundation for future bridge inspections and investigations.This study demonstrates the effectiveness of combining digital twin technology with field measurements for real-time monitoring and predictive maintenance,ensuring the sustainability and safety of the bridge infrastructure,thereby enhancing its overall resilience to operational and environmental stressors. 展开更多
关键词 Digital twin Structural health monitoring balanced cantilever bridge 3D-LiDAR Dynamic strain measurement
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Handover management in beyond 5G HetNet topologies with unbalanced user distribution
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作者 Abdussamet Hatipoglu Mehmet Akif Yazici +2 位作者 Mehmet Basaran Mine Ardanuc Lutfiye Durak-Ata 《Digital Communications and Networks》 2025年第2期465-472,共8页
The increase in user mobility and density in modern cellular networks increases the risk of overloading certain base stations in popular locations such as shopping malls or stadiums,which can result in connection loss... The increase in user mobility and density in modern cellular networks increases the risk of overloading certain base stations in popular locations such as shopping malls or stadiums,which can result in connection loss for some users.To combat this,the traffic load of base stations should be kept as balanced as possible.In this paper,we propose an efficient load balancing-aware handover algorithm for highly dynamic beyond 5G heterogeneous networks by assigning mobile users to base stations with lighter loads when a handover is performed.The proposed algorithm is evaluated in a scenario with users having different levels of mobility,such as pedestrians and vehicles,and is shown to outperform the conventional handover mechanism,as well as another algorithm from the literature.As a secondary benefit,the overall energy consumption in the network is shown to be reduced with the proposed algorithm. 展开更多
关键词 Beyond 5G Handover management Load balancing Markov chain Poisson point process Poisson hole process Ultra-dense heterogeneous network
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ICPA-LQR优化的两轮平衡机器人自稳定与轨迹跟踪PID控制器设计
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作者 黄鹤 李文龙 +3 位作者 杨澜 王会峰 高涛 陈婷 《哈尔滨工业大学学报》 北大核心 2026年第2期198-210,共13页
针对现有两轮平衡机器人线性二次型调节器(LQR)的权重系数需要手动选取的缺陷,提出了一种利用改进的食肉植物算法(ICPA)优化LQR权重系数的方法,实现了两轮平衡机器人的自稳定与高精度轨迹跟踪。首先,利用拉格朗日方程法构建了两轮平衡... 针对现有两轮平衡机器人线性二次型调节器(LQR)的权重系数需要手动选取的缺陷,提出了一种利用改进的食肉植物算法(ICPA)优化LQR权重系数的方法,实现了两轮平衡机器人的自稳定与高精度轨迹跟踪。首先,利用拉格朗日方程法构建了两轮平衡机器人系统动力学方程,采用LQR优化PID控制策略保证其最优控制力;其次,在食肉植物算法(CPA)成长过程中引入自适应捕捉系数,平衡食肉植物和猎物的成长关系,提升了前期全局探索和后期局部寻优能力;然后,在CPA繁殖过程中设计干扰因子,扩大搜索空间,进一步提升全局寻优能力;最后,基于EA代价函数,利用ICPA对LQR控制器的权重系数进行寻优,并在MATLAB/Simulink环境中建立两轮平衡机器人控制策略模型。实验结果表明,提出的ICPA-LQR优化的PID控制器,相较于食肉植物算法、麻雀搜索算法、飞蛾扑火算法和改进粒子群算法优化的控制器,动态响应速度更快、抗干扰能力更强、整体性能更好。在扰动情况下,控制两轮平衡机器人跟踪复杂轨迹时,倾角动态偏差小于0.05 rad、横纵坐标的偏差均小于0.2 m、转向角偏差小于0.2 rad、车轮位置角偏差小于3 rad,可以在保持动态平衡的前提下精确跟踪给定的参考轨迹,具有较强的泛化能力。 展开更多
关键词 控制器设计 两轮平衡机器人 动力学建模 改进食肉植物算法 轨迹跟踪
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坚持全方位扩大内需与优化供给有机结合破解内需不足难题——学习《习近平经济文选》第一卷的体会
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作者 郝身永 《当代经济管理》 北大核心 2026年第3期1-13,共13页
2025年3月出版的《习近平经济文选》第一卷是深入学习领会习近平经济思想的权威著作。文章系统梳理了该著作中关于扩大内需的相关论述,主要有三大体会:一是习近平总书记提出把扩大内需作为战略基点,在内需中突出强调消费,背后的理论基... 2025年3月出版的《习近平经济文选》第一卷是深入学习领会习近平经济思想的权威著作。文章系统梳理了该著作中关于扩大内需的相关论述,主要有三大体会:一是习近平总书记提出把扩大内需作为战略基点,在内需中突出强调消费,背后的理论基础是马克思社会再生产理论,并在开放经济条件下进行了创新性发展,强调供需对立统一的辩证关系,超越了单纯从需求侧或供给侧进行割裂式分析的局限。二是当前我国内需不足突出地表现为消费不振,这既有需求侧原因,也有供给侧原因。我国的低消费率与高速增长时期投资驱动的增长模式有关,该模式具有内生机制,但其维持又有限度,低消费率与投资驱动模式衰竭叠加导致当前的内需不足。三是扩大内需提振消费需要供需两侧协同发力,把需求侧管理和优化供给有机结合起来。在需求侧,要实施更加积极的财政政策和适度宽松的货币政策,全方位扩大内需,但要避免强刺激带来供给无序扩张。在供给侧,关键是减少无效、低效投资,形成有效供给,这需要减少政府对资源配置的不当干预,让企业在产业创新和科技创新中发挥主体作用,激发企业家精神,提升企业创新对需求变动的捕捉力、引领力,从而提高供给与需求的适配度。 展开更多
关键词 扩大内需 提振消费 优化供给 供需平衡
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一种用于微带半波振子天线的新型BALUN 被引量:4
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作者 卢晓鹏 李雁 李昂 《雷达科学与技术》 2006年第4期236-239,共4页
通过将常规的空气板线BALUN微带化,从而建立一种新型微带BALUN。该BALUN引入一个并联谐振电路,可以有效补偿半波振子的串联电抗而实现微带半波振子带宽的最大化。采用此种BAL-UN设计制作了一个L波段微带偶极子天线单元。测试结果表明:... 通过将常规的空气板线BALUN微带化,从而建立一种新型微带BALUN。该BALUN引入一个并联谐振电路,可以有效补偿半波振子的串联电抗而实现微带半波振子带宽的最大化。采用此种BAL-UN设计制作了一个L波段微带偶极子天线单元。测试结果表明:该半波振子天线在21.8%的带宽内驻波比优于1.18,带内交叉极化优于-21 dB,接近理论最大设计带宽。 展开更多
关键词 微带balun 微带偶极子天线 宽带
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基于改进动麦优化模糊C-均值的WSN分簇信誉路由算法
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作者 韩冰青 温锦笑 《计算机应用研究》 北大核心 2026年第1期240-246,共7页
针对无线传感器网络中分簇不均、节点能耗高及路由安全性低等问题,提出一种基于改进动麦优化模糊C-means的WSN分簇信誉路由算法(IFCAOR)。首先利用改进的动麦算法优化模糊C-means算法的初始聚类中心,提高网络分簇效果。其次,在簇首选举... 针对无线传感器网络中分簇不均、节点能耗高及路由安全性低等问题,提出一种基于改进动麦优化模糊C-means的WSN分簇信誉路由算法(IFCAOR)。首先利用改进的动麦算法优化模糊C-means算法的初始聚类中心,提高网络分簇效果。其次,在簇首选举阶段,综合节点能量、距离等因素,动态选择簇首,实现负载均衡。最后,在数据传输阶段,采用单多跳轮询机制,并结合中继节点的负载、信誉值和路径衰减等构建路由适应度函数,利用改进动麦算法规划高效安全的传输路由,降低节点能耗并提高路由安全性。仿真结果表明,IFCAOR算法的网络生命周期较LEACH、IFCRA和HMABFOA分别提升93%、49.6%和34.3%,IFCAOR算法能有效平衡网络负载,延长网络生命周期。 展开更多
关键词 无线传感器网络 模糊C-均值 动麦优化算法 分簇路由 能耗均衡
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ELGR:An Energy-efficiency and Load-balanced Geographic Routing Algorithm for Lossy Mobile Ad Hoc Networks 被引量:2
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作者 王国栋 王钢 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第3期334-340,共7页
Geographic routing is a highly active area of research in mobile ad hoc networks (MANETs) owing to its efficiency and scalability. However,the use of simple greedy forwarding decreases the packet reception rate (PR... Geographic routing is a highly active area of research in mobile ad hoc networks (MANETs) owing to its efficiency and scalability. However,the use of simple greedy forwarding decreases the packet reception rate (PRR) dramatically in unreliable wireless environments; this also depresses the network lifetime. Therefore,it is important to improve delivery performance and prolong MANET lifetime simultaneously. In this article,a novel geographic routing algorithm,named energy-efficiency and load-loalanced geographic routing (ELGR),is presented for lossy MANETs. ELGR combines energy efficiency and load balance to make routing decisions. First,a link estimation scheme for the PRR is presented that increases the network energy efficiency level. Second,a learning method is proposed to adaptively sense local network loads,allowing enhanced whole network load balance. The results of a simulation show that ELGR performs better than several other geographic routing algorithms; in particular it extends network lifetime by about 20%,with a higher delivery ratio. 展开更多
关键词 MANET geographic routing energy efficiency load balance FORWARDING
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基于种养结合的大通县畜禽粪污土地承载力研究
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作者 张荣 王亚艺 +3 位作者 张玮 李生全 郭继军 李松龄 《畜牧兽医杂志》 2026年第1期12-20,共9页
通过评估青海省大通县各乡畜禽养殖规模分布和土地承载力状况,为优化区域养殖分布结构,推动可持续性种养结合畜牧业提供理论参考。采用农田氮养分平衡法,测算分析了大通县各乡镇畜禽粪污土地承载力、单位农用地承载力和种养平衡状况。... 通过评估青海省大通县各乡畜禽养殖规模分布和土地承载力状况,为优化区域养殖分布结构,推动可持续性种养结合畜牧业提供理论参考。采用农田氮养分平衡法,测算分析了大通县各乡镇畜禽粪污土地承载力、单位农用地承载力和种养平衡状况。结果表明:以氮养分计算的2023年大通县土地承载力为91.38万头猪当量,单位农用地畜禽养殖土地承载力为20.14头/hm^(2),承载力指数为1.07,与大通县实际养殖总量97.69万头猪当量、单位农用地承载力21.53头/hm^(2)相比,说明大通县实际畜禽养殖量高于理论最大值;畜禽粪污土地承载力指数石山乡、极乐乡、多林镇、斜沟乡、青林乡和宝库乡均大于1,结合GIS空间分析图,以上各乡镇存在超载状况。因此,建议县域内进行种养殖优化和加强畜禽粪污处理能力,调整畜禽养殖规模,实施乡镇间协同管理,优化种养结构,推进种养结合十分必要。 展开更多
关键词 种养结合 畜禽粪污 氮养分平衡法 土地承载力 承载力指数
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带有小型化Balun的C波段单片GaAs pHEMT单平衡电阻性混频器 被引量:1
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作者 李志强 张健 张海英 《电子学报》 EI CAS CSCD 北大核心 2008年第12期2454-2457,共4页
本文介绍了一种带有小型化无源Balun的C波段单片GaAs pHEMT单平衡电阻性混频器。Balun采用集总一分布式结构,使其长度与常用2/4耦合线Balun相比缩小了11倍,大大降低了将无源Balun应用于C波段单片集成电路中所需的芯片尺寸。混频器采... 本文介绍了一种带有小型化无源Balun的C波段单片GaAs pHEMT单平衡电阻性混频器。Balun采用集总一分布式结构,使其长度与常用2/4耦合线Balun相比缩小了11倍,大大降低了将无源Balun应用于C波段单片集成电路中所需的芯片尺寸。混频器采用单平衡电阻性结构,在零功耗的情况下实现了良好的线性和口间隔离性能。测试结果显示,在固定中频160MHz,本振输入功率0dBm条件下,在3.5~5GI-IzRF频带内,最小变频损耗为8.3dB,1dB压缩点功率为8.0dBm,LO至Ⅲ之问的隔离度为38dB。 展开更多
关键词 砷化镓基赝配高电子迁移率晶体管 电阻性混频器 小型化balun 集总-分布式
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人类活动对鄱阳湖流域水文干旱演变特征的影响
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作者 姚仕明 姚立强 《湖泊科学》 北大核心 2026年第1期339-352,I0047,共15页
为定量评估人类活动对鄱阳湖流域水文干旱特征的影响,基于1959-2022年流域内气象水文站点的实测数据,分析降水、气温、蒸发及径流序列的年际变化趋势。采用双累积曲线法,绘制鄱阳湖五大流域分区的累积年降水量-径流深关系曲线,根据曲线... 为定量评估人类活动对鄱阳湖流域水文干旱特征的影响,基于1959-2022年流域内气象水文站点的实测数据,分析降水、气温、蒸发及径流序列的年际变化趋势。采用双累积曲线法,绘制鄱阳湖五大流域分区的累积年降水量-径流深关系曲线,根据曲线斜率变化情况,结合突变点检验,确定人类活动影响的基准期和变化期。采用两参数月水量平衡模型,依据各阶段月降水、蒸发和径流实测数据,分阶段率定模型参数,并利用纳什效率系数、相关系数及水量平衡误差检验模拟效果。通过对基准期、变化期模拟月径流深的还现、还原计算及其相对差值分析,量化气候变化和人类活动对径流的影响。以单月标准化径流指数(SRI)为干旱指标,运用游程理论识别变化期的干旱事件,对比分析参数还原前后的年平均累积干旱烈度、单次干旱最大烈度及干旱次数等特征。结果显示,总体上人类活动减小了流域的径流深,且对枯水期影响更为显著。空间上,抚河和饶河流域受影响最为明显,年平均径流深较基准期分别下降8.5%和9.2%,枯水期径流深下降12.0%和12.3%。变化期鄱阳湖流域水文干旱频次和烈度较基准期整体增加,年均干旱次数、年均干旱烈度和单次干旱最大烈度分别增加约21.3%、55.4%和24.3%。该研究可为鄱阳湖流域干旱趋势的长期预测提供参考。 展开更多
关键词 水文干旱 鄱阳湖流域 人类活动影响 月水量平衡模型 双累积曲线
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Effects of Balanced Fertilization on Mulberry Leaf Quality and Its Active Substance Content 被引量:1
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作者 黄盖群 张烈 +6 位作者 殷浩 危玲 佟万红 刘刚 张建华 林超文 郭涛 《Agricultural Science & Technology》 CAS 2013年第4期635-639,644,共6页
This paper study the effect of nitrogen (N, X1), phosphorus (P, X2) and potassium (K, X3) in different amounts on crude protein, soluble sugar, total flavonoid and 1-deoxynojirimycin contents in mulberry leaves,... This paper study the effect of nitrogen (N, X1), phosphorus (P, X2) and potassium (K, X3) in different amounts on crude protein, soluble sugar, total flavonoid and 1-deoxynojirimycin contents in mulberry leaves, with mulberry trees in spring and autumn as the material and as per "3414" experimental design. The results showed that the qualities and active substance content of mulberry leaves changed from increasing to decreasing with its development; crude protein and solu-ble sugar achieved the peak on August 20; total flavonoid and 1-deoxynojirimycin was the highest on May 15. Fertilizations with N, P and K fertilizers at different amounts had significant effects on quality of mulberry leaf and content of active substances. Specifically, as fertilizer amount increased, the content of active sub- stances grew dramatically and achieved the highest at level 2 (X^2X=X~_). Based on fertilizer effect functions of objective yield, the recommended amounts of N, P and K fertilizers based on crude protein, soluble sugar, flavonoid content and DNJ in test sites were 718.46, 220.11 and 305.23 kg/hm2, when the highest of crude protein in mulberry leaf was 1 813.83 kg/hm2. When N, P and K fertilizers were recommended at 666.54, 204.41 and 243.18 kg/hm2, soluble sugar in mulberry leaf achieved the peak at 1 042.65 kg/hm2. When N, P and K fertilizers were at 675.96, 326.49 and 462.90 kg/hm2, flavonoid content achieved the maximum at 147.90 kg/hm2. When N, P and K fertilizers were at 720.9, 225.11 and 323.63 kg/hm2, DNJ content was the highest at 13.55 kg/hm2. 展开更多
关键词 MULBERRY balanced fertilization QUALITY Active substances
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