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A Superimposed Pilot with Transition Band Channel Estimation Scheme for OTFS
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作者 He Xiandeng Shu Kai Yi Yunhui 《China Communications》 2026年第1期107-124,共18页
The orthogonal time frequency space(OTFS)modulation is a novel modulation scheme that can effectively cope with the high Doppler expansion caused by high mobility.Since it modulates data on delay-Doppler(DD)domain and... The orthogonal time frequency space(OTFS)modulation is a novel modulation scheme that can effectively cope with the high Doppler expansion caused by high mobility.Since it modulates data on delay-Doppler(DD)domain and makes full use of the sparse characteristics of DD domain,it has been widely studied to design efficient channel estimation and signal detection schemes.In this paper,we design a novel superimposed pilot pattern with transition band,which replaces the traditional embedded pilot(EP)guard zero-symbols,and perform a two-stage channel estimation.In the first stage,we fully utilize the dispersion characteristics of OTFS signal in DD domain,and use threshold decision to make coarse channel estimation.In the second stage,we use the results of the coarse estimation for iterative signal detection and accurate channel estimation.During the second stage,we make full use of the sparsity of the channel in DD domain,remodel the received signal into the form of sparse channel vector multiplied by channel coefficient matrix,and introduce Doppler index segmentation factor(DISF)to subdivide the Doppler index to solve the problem of fractional Doppler.Simulations reveal that,the scheme proposed in this paper has higher spectral efficiency compared with traditional EP scheme and lower peak-to-average power ratio(PAPR)compared with traditional superimposed pilot scheme. 展开更多
关键词 channel estimation OTFS signal detection superimposed pilot
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Pollution and carbon reduction effects of the pilot policy on clean winter heating in Northern China:Evidence from the county level 被引量:1
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作者 Yan Chen Jiaqi Li +1 位作者 Yue Zhang Fan Yang 《Chinese Journal of Population,Resources and Environment》 2025年第1期85-95,共11页
Coal dependence and inefficient decentralized heating have significantly increased China’s energy consumption for winter heating,increasing air pollution and exacerbating the greenhouse effect.In 2017,China implement... Coal dependence and inefficient decentralized heating have significantly increased China’s energy consumption for winter heating,increasing air pollution and exacerbating the greenhouse effect.In 2017,China implemented the Pilot Policy on Clean Winter Heating in Northern China,aiming to achieve high central heating coverage and cleaner energy consumption.Studying the effects of this policy can help promote its implementation and serve as a reference for effective adjustment of the contents in the future.However,few studies have investigated this policy and its carbon reduction effects,and most focus on the provincial or city levels.Therefore,this paper considers the policy’s influence on air pollution and carbon emissions at the county level to provide a precise and comprehensive assessment of the policy effects.We use panel data from 1290 counties in 15 provinces in Northern China from 2014 to 2021,applying a multiperiod difference-in-differences model to quantify the impact of the policy on carbon emissions and air quality in the pilot area.We then conduct a series of tests to demonstrate the robustness of the results and analyze the mechanisms of the policy effects from two perspectives,namely,central heating and natural gas use,through a mediating effect model.Finally,we examine the heterogeneity of policy effects between counties based on geographic location and per capita income levels of rural residents through a moderating effect model.The results reveal that the policy significantly reduces air pollution and carbon emissions in the pilot area by increasing the central heating area and natural gas use.Compared with the central and western regions in the north and areas with low-income rural residents,the policy effects in the eastern regions in the north and areas with high-income rural residents are more pronounced. 展开更多
关键词 pilot policy on clean winter heating Pollution and carbon reduction Multiperiod difference-in-differences model County-level analysis Northern China
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The serum fascin-1 and tumor components containing this protein in patients with head and neck squamous cell carcinoma:A pilot study 被引量:1
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作者 Gelena V.Kakurina Elena E.Sereda +4 位作者 Marina N.Stakheeva Liubov Tashireva Olga V.Cheremisina Irina V.Kondakova Evgeny L.Choinzonov 《Journal of Biomedical Research》 2025年第5期534-537,I0046,I0047,共6页
Dear Editor,Local recurrence and cervical lymph node metastases are major causes of mortality in patients with head and neck squamous cell carcinoma(HNSCC).To date,none of the proposed strategies for predicting outcom... Dear Editor,Local recurrence and cervical lymph node metastases are major causes of mortality in patients with head and neck squamous cell carcinoma(HNSCC).To date,none of the proposed strategies for predicting outcomes in this disease have proven fully effective,and a comprehensive physical examination remains the primary method for early detection and monitoring of HNSCC. 展开更多
关键词 serum fascin cervical lymph node metastases tumor components comprehensive physical examination head neck squamous cell carcinoma hnscc head neck squamous cell carcinoma pilot study local recurrence
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浅析奥维互动地图3D视角和DJI Pilot飞控软件在森林资源调查监测中的应用技术
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作者 覃道彪 《内蒙古林业调查设计》 2025年第2期58-60,75,共4页
随着科技的不断进步,森林资源调查监测领域正经历着一场技术革命。文章探析使用奥维互动地图制作调查图层底图,结合大疆无人机和DJI Pilot飞控软件进行无人机航点规划与飞行控制,实现森林资源的高效、精准调查和监测,具体流程包括调查... 随着科技的不断进步,森林资源调查监测领域正经历着一场技术革命。文章探析使用奥维互动地图制作调查图层底图,结合大疆无人机和DJI Pilot飞控软件进行无人机航点规划与飞行控制,实现森林资源的高效、精准调查和监测,具体流程包括调查图层底图的制作、无人机航点的规划与导入、利用奥维互动地图3D视角进行作业区域的三维可视化,以及运用手控无人机进行航点飞拍,以期提高数据采集的速度和质量、增强森林资源的实时监控能力。 展开更多
关键词 森林资源调查监测 奥维互动地图 DJI pilot飞控软件 大疆无人机
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Interference Cancellation Based Neural Receiver for Superimposed Pilot in Multi-Layer Transmission
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作者 Xiao Han Tian Wenqiang +4 位作者 Jin Shi Liu Wendong Shen Jia Shi Zhihua Zhang Zhi 《China Communications》 2025年第1期75-88,共14页
In this paper,an interference cancellation based neural receiver for superimposed pilot(SIP)in multi-layer transmission is proposed,where the data and pilot are non-orthogonally superimposed in the same time-frequency... In this paper,an interference cancellation based neural receiver for superimposed pilot(SIP)in multi-layer transmission is proposed,where the data and pilot are non-orthogonally superimposed in the same time-frequency resource.Specifically,to deal with the intra-layer and inter-layer interference of SIP under multi-layer transmission,the interference cancellation with superimposed symbol aided channel estimation is leveraged in the neural receiver,accompanied by the pre-design of pilot code-division orthogonal mechanism at transmitter.In addition,to address the complexity issue for inter-vendor collaboration and the generalization problem in practical deployments,respectively,this paper also provides a fixed SIP(F-SIP)design based on constant pilot power ratio and scalable mechanisms for different modulation and coding schemes(MCSs)and transmission layers.Simulation results demonstrate the superiority of the proposed schemes on the performance of block error rate and throughput compared with existing counterparts. 展开更多
关键词 interference cancellation model scalability neural receiver superimposed pilot
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Monitoring of urinary iodine concentration in naval pilots:should iodine be supplemented or limited at coastal stations?
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作者 Jia Zeng Qi Li +7 位作者 Xiang Lu Dan-Dan Liu Rong-Guan Jiao Yan-Qing Jiang Yan-Bing Liu Wan-Qing Xu Jun Ma Guo-Li Gu 《Military Medical Research》 2025年第1期154-156,共3页
Dear Editor,In recent years,there has been a significant upward trend in the detection rate of thyroid diseases among military flight personnel[1].Thyroid diseases not only pose a serious threat to the health of fligh... Dear Editor,In recent years,there has been a significant upward trend in the detection rate of thyroid diseases among military flight personnel[1].Thyroid diseases not only pose a serious threat to the health of flight personnel but also have negative impacts on the aviation safety and combat effectiveness of troops.It has been confirmed that the occurrence and progression of thyroid diseases are closely linked to dietary iodine intake.Studies have manifested that long-term excessive or insufficient iodine intake can lead to thyroid diseases[2,3]. 展开更多
关键词 Naval pilot THYROID Urinary iodine
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Assessing waste classification in rural China:A framework for selecting pilot regions
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作者 CAO Chao-xue 《Ecological Economy》 2025年第3期228-243,共16页
Before nationwide implementation of waste classification programs in rural areas,identifying suitable pilot regions is crucial.This study develops a comprehensive framework for assessing and selecting these pilot regi... Before nationwide implementation of waste classification programs in rural areas,identifying suitable pilot regions is crucial.This study develops a comprehensive framework for assessing and selecting these pilot regions.Data were collected through 654 valid questionnaires and interviews with respondents from rural areas in six provinces across China.Primary assessment criteria included disposal methods for kitchen waste,recyclables,hazardous waste,and residual waste,as well as farmers’willingness to separate hazardous waste when offered compensation and the impact of centralized waste treatment in villages.Secondary criteria focused on disposal methods for agrochemical packages and other hazardous waste.Using the weighted sum of squares method,the study evaluated the suitability of six regions as pilot areas for waste classification.The results identified villages in Jiangsu province and Hebei province as the most suitable pilot regions.Based on the findings,the study provides recommendations to address weaknesses in these regions to enhance the effectiveness of future trials and offers tailored suggestions for other regions to improve their waste classification initiatives. 展开更多
关键词 ASSESSING waste classification rural China pilot regions
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Pilot-scale case study on vanadium extraction from vanadium-bearing shale using suspension oxidation roasting-curing-leaching process
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作者 Zhe BAI Jia-hao HE +4 位作者 Ming-xing WANG Yue-xin HAN Yong-sheng SUN Shuai YUAN Jian-ping JIN 《Transactions of Nonferrous Metals Society of China》 2025年第9期3161-3178,共18页
Addressing the environmental issues of traditional vanadium extraction methods from vanadium-bearing shale,a highly efficient and clean suspension oxidation roasting-curing-leaching process was proposed and semi-indus... Addressing the environmental issues of traditional vanadium extraction methods from vanadium-bearing shale,a highly efficient and clean suspension oxidation roasting-curing-leaching process was proposed and semi-industrial trials were conducted.Vanadium in raw ore mainly exists in sericite,roscoelite,and limonite,predominantly in the forms of V(Ⅲ)and V(Ⅳ).Under the conditions of a feed rate of 30 kg/h,an air flow rate of 28.0 m^(3)/h,an O_(2) flow rate of 4.0 m^(3)/h,and a temperature of 900℃ in both the suspension furnace and fluidized reactor,the vanadium-bearing mica underwent dehydroxylation and transformed into illite-montmorillonite.These changes disrupted the crystal structure of mica,facilitating vanadium extraction.Compared to direct acid leaching,curing-leaching demonstrates better performance in vanadium extraction.Under the conditions of curing temperature of 130℃,acid dosage of 40 wt.%,curing time of 6 h,and leaching time of 3 h,a V_(2)O_(5) leaching efficiency of 83.92% was achieved. 展开更多
关键词 V-bearing shale suspension roasting curing-leaching pilot case mineralogy
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Pilot plant design and technology performance analysis of pervaporation membrane bioreactor with mechanical vapor compression for bioethanol production
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作者 Jingyun Liu Yin Zhang +4 位作者 Wenda Liu Haoji Jiang Lu Han Zeyi Xiao Senqing Fan 《Chinese Journal of Chemical Engineering》 2025年第6期57-66,共10页
A pilot plant integrating pervaporation membrane bioreactor and mechanical vapor compression for bioethanol production was designed and constructed in the study,with a bioethanol production of 300 t·a^(-1).Key eq... A pilot plant integrating pervaporation membrane bioreactor and mechanical vapor compression for bioethanol production was designed and constructed in the study,with a bioethanol production of 300 t·a^(-1).Key equipment in the process were designed based on bench test data.A pilot-scale fermenter with 20 m^(3) in volume,4 m in height and 2.5 m in diameter was designed based on geometric similarity criterion and power equality criterion.An integrated plate-frame membrane module with 105 plates was newly developed.Compared with conventional batch fermentation,the improvement of equipment utilization efficiency and the cell utilization efficiency can be expected as 1.5-2.0 times and 2-10 times,respectively,with waste water reduced by 70% to 85%.The high-exergy energy requirement for pilot plant was 57.5 k W,of which the broth preheater occupied 85.7%,following by the compressor 1.1%,pump1.9% and fermenter agitator 0.3%.The total energy requirement including distillation for producing 1 kg ethanol(95%(mass)) achieved an energy surplus of 15.6 MJ. 展开更多
关键词 Membrane bioreactor Bioethanol production Technology performances pilot plant Energy requirement
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Bioenergy recovery and carbon emissions benefits of short-term bio-thermophilic pretreatment on low organic sewage sludge anaerobic digestion:A pilot-scale study
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作者 Hui Wang Xiang Fu +5 位作者 Haozhe Huang Danni Shen Dongdong Fan Liming Zhu Xiaohu Dai Bin Dong 《Journal of Environmental Sciences》 2025年第2期321-335,共15页
Sewage sludge in cities of Yangzi River Belt,China,generally exhibits a lower organic content and higher silt contentdue to leakage of drainage system,which caused low bioenergy recovery and carbon emission benefits i... Sewage sludge in cities of Yangzi River Belt,China,generally exhibits a lower organic content and higher silt contentdue to leakage of drainage system,which caused low bioenergy recovery and carbon emission benefits in conventional anaerobic digestion(CAD).Therefore,this paper is on a pilot scale,a bio-thermophilic pretreatment anaerobic digestion(BTPAD)for low organic sludge(volatile solids(VS)of 4%)was operated with a long-term continuous flow of 200 days.The VS degradation rate and CH_(4) yield of BTPAD increased by 19.93%and 53.33%,respectively,compared to those of CAD.The analysis of organic compositions in sludge revealed that BTPAD mainly improved the hydrolysis of proteins in sludge.Further analysis of microbial community proportions by high-throughput sequencing revealed that the short-term bio-thermophilic pretreatment was enriched in Clostridiales,Coprothermobacter and Gelria,was capable of hydrolyzing acidified proteins,and provided more volatile fatty acid(VFA)for the subsequent reaction.Biome combined with fluorescence quantitative polymerase chain reaction(PCR)analysis showed that the number of bacteria with high methanogenic capacity in BTPAD was much higher than that in CAD during the medium temperature digestion stage,indicating that short-term bio-thermophilic pretreatment could provide better methanogenic conditions for BTPAD.Furthermore,the greenhouse gas emission footprint analysis showed that short-term bio-thermophilic pretreatment could reduce the carbon emission of sludge anaerobic digestion system by 19.18%. 展开更多
关键词 Sludge Anaerobic digestion Bio-thermophilic pretreatment pilot scale Molecular microbiology Carbon emissions
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A pilot randomized controlled trial of KangminⅠdecoction as a treatment for atopic eczema
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作者 MA Tian XIAO Qingqing +11 位作者 FEI Xiaoya ZHAO Huaibo LIU Liu CHAI Yuanyuan SUN Xiaoying WANG Yifei XU Rong CHEN Jie ZHOU Mi QIN Wanzhang LI Bin LI Xin 《World Journal of Integrated Traditional and Western Medicine》 2025年第1期10-18,共9页
Background:Atopic eczema is the most common type of skin disorder in both children and adults.It is characterized by erythema,pruritus,papules,xeransis,and lichenification.The KangminⅠdecoction,a Chinese herbal medic... Background:Atopic eczema is the most common type of skin disorder in both children and adults.It is characterized by erythema,pruritus,papules,xeransis,and lichenification.The KangminⅠdecoction,a Chinese herbal medicine prepared with several ingredients and used to treat eczema,was formulated according to traditional Chinese medicine theory.Objectives:To investigate the efficacy and safety of KangminⅠdecoction for treating atopic eczema compared to that of loratadine.Methods:90 patients were enrolled at the Yueyang Hospital of Integrated Traditional Chinese and Western Medicine and randomly divided into the KangminⅠdecoction treatment group(n=45)and loratadine control group(n=45).Clinical efficacy was evaluated using the Eczema Area and Severity Index(EASI),Dermatology Life Quality Index(DLQI),adverse events(AEs),and recurrence rates,which were compared between the groups.Results:Compared to the loratadine control group(51.16%,18.60%),the KangminⅠdecoction group(7.72%,4.55%)displayed a significantly reduced effective rate(x^(2)=8.324,P=0.040)and recurrence rate(x^(2)=4.225,P=0.040).The incidence of AEs was similar between the groups(P=0.502).Conclusions:These results support further development of KangminⅠdecoction for the treatment of eczema.The KangminⅠdecoction showed good efficacy with a low recurrence rate and tolerable AEs.The main limitations of this study include the small sample size and the short treatment and follow-up periods.Larger controlled studies are needed to more adequately evaluate both safety and efficacy. 展开更多
关键词 Atopic eczema The KangminⅠdecoction pilot randomized controlled trial
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Hot melt emulsification shear method for solid lipid-based suspension:from laboratory-scale to pilot-scale production
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作者 Chao Li Wenqing Xie +3 位作者 Liwen Yuan Mubbashar Abbas Dongmei Chen Shuyu Xie 《Animal Diseases》 2025年第2期235-247,共13页
The clinical application of solid lipid particles(SLPs)is hampered due to the need for advanced nano/micro-suspension production technology.This research aims to establish a pilot-scale production line employing high-... The clinical application of solid lipid particles(SLPs)is hampered due to the need for advanced nano/micro-suspension production technology.This research aims to establish a pilot-scale production line employing high-speed shears as emulsification equipment.The primary purpose is to manufacture nano/micro-suspensions using solid lipid particles(SLPs).The study also exhaustively introduces and analyzes the regulatory schemes for process parameters and formulations at various stages of production.The process and formulation endured optimization through orthog-onal or single-factor tests at various production steps:laboratory research,small-scale trial production,and pilot production.Quality standards for the product were determined,and key parameters were obtained at each stage.The laboratory research demonstrated that the optimal SLPs comprised 15 mL 3%polyvinyl alcohol(PVA)per 1.0 g tilmicosin and 2.5 g carnauba wax(WAX).During small-scale production,modifications were made to the volume of the aqueous phase,emulsifier concentration,and emulsification strength,setting them to 16 mL,5%,and 2200 r/min,respectively.In the pilot production stage,the shear time was considered optimal at eight min.The impurity,content,polydispersion coefficient(PDI),and size of the pilot product were<3%,5%,0385 and 2.64μm,respectively.Among the several parameters studied,heating temperature,drug-lipid ratio,and emulsifier concentration were identified as the main factors affecting product quality,and they were regulated at 100℃,1:3,and 5%,respectively.A novel hot melt emulsification shear method aided the development of a new solid lipid-based suspension from its preliminary stages in the laboratory to pilot production.This innovation is expected to enhance solid lipid-based suspensions'industrial evolution extensively. 展开更多
关键词 Laboratory research Small-scale production pilot production Quality evaluation Solid lipid particles
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Research on the Impact of the Construction of Cross-border E-commerce Comprehensive Pilot Zones on China’s Export Transformation and Upgrading
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作者 Jiahui Zhao 《Proceedings of Business and Economic Studies》 2025年第6期45-52,共8页
Cross-border e-commerce has emerged as a new growth point in foreign trade.While the Dalian comprehensive pilot zone has made some progress,its development is constrained by issues such as the global economic slowdown... Cross-border e-commerce has emerged as a new growth point in foreign trade.While the Dalian comprehensive pilot zone has made some progress,its development is constrained by issues such as the global economic slowdown,the relatively small scale of cross-border e-commerce,a high concentration of export commodities,imperfect information mechanisms,and high overall costs.To address these challenges,this paper explores the importance of the construction of the Dalian comprehensive pilot zone for cross-border e-commerce to the transformation and upgrading of exports.Based on my research project,“Research on Path Optimization of Financial Support for the Development of Advanced Manufacturing Clusters in Dalian,”this paper analyzes the current challenges and limiting factors and proposes corresponding countermeasures and suggestions. 展开更多
关键词 Cross-border e-commerce comprehensive pilot zone Cross-border e-commerce Export transformation and upgrading Foreign trade export
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China’s Pilot Carbon Market:Institutional Design for Industrial Low-Carbon Transition
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作者 Wang Wenju Qian Xinxin 《China Economist》 2025年第5期46-67,共22页
This study explores the mechanisms by which China’s pilot carbon emissions trading schemes(ETS)facilitate industrial low-carbon transitions.We construct a theoretical model and conduct an empirical analysis using pro... This study explores the mechanisms by which China’s pilot carbon emissions trading schemes(ETS)facilitate industrial low-carbon transitions.We construct a theoretical model and conduct an empirical analysis using provincial panel data from seven pilot provinces spanning 2006-2021.Applying a multi-period difference-in-differences(DID)approach,we evaluate the environmental and economic impacts of the pilot ETS policies.The findings yield three key insights:(1)The pilot ETS significantly reduces carbon emission intensity and improves low-carbon total factor productivity(TFP),thereby promoting China’s industrial low-carbon transition.(2)Mechanism analysis indicates that the ETS primarily operates through cost constraints and industrial structural upgrading,while the effect of technological progress has yet to fully materialize.(3)Heterogeneity analysis reveals that the policy’s effects are more significant in regions with higher levels of economic development and R&D investment,leading to greater carbon intensity reductions and productivity gains.In addition,regions with higher foreign direct investment(FDI)experience more substantial improvements in low-carbon TFP,possibly reflecting technology spillover effects. 展开更多
关键词 pilot carbon emissions trading scheme Industrial low-carbon transition National unified carbon market Carbon emission intensity Low-carbon total factor productivity
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The Impact of Establishing Pilot Free Trade Zones on Integration Into the Digital Global Value Chain
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作者 Xie Dan 《Contemporary Social Sciences》 2025年第2期103-118,共16页
This study utilizes panel data from 293 Chinese cities at the prefecture level or above,spanning from 2013 to 2022,to empirically examine the net effects and underlying mechanisms of establishing pilot free trade zone... This study utilizes panel data from 293 Chinese cities at the prefecture level or above,spanning from 2013 to 2022,to empirically examine the net effects and underlying mechanisms of establishing pilot free trade zones(FTZs)on integration into the digital global value chain(DGVC).The results demonstrate that the establishment of pilot FTZs positively promotes integration into the DGVC and generates a spatial spillover effect.Compared to coastal areas and small-and medium-sized cities,pilot FTZs have a more significant impact on the integration of inland regions and large cities into the DGVC.Mechanism tests reveal that pilot FTZs drive integration into the DGVC primarily by promoting digital industry agglomeration and enhancing the technological content of exports.Furthermore,bilateral foreign direct investment and digital trade rules positively amplify the impact of pilot FTZs on integration into the DGVC.Therefore,this study recommends comprehensively deepening the development of pilot FTZs,consistently enhancing the technological content of exports,and proactively establishing a sound digital trade regulatory framework.These recommendations offer valuable insights for DGVC integration and the construction of a high-standard free trade network. 展开更多
关键词 pilot free trade zone(FTZ) integration into digital global value chain(DGVC) digital industry agglomeration content of technology exports
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数据要素集聚对地方财政韧性的影响研究——基于国家级大数据综合试验区的经验证据 被引量:1
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作者 蒋团标 张家良 马国群 《经济与管理评论》 北大核心 2026年第1期54-65,共12页
为探究数据要素的价值创造与经济潜力对地方财政韧性的作用与机制,以国家级大数据综合试验区作为准自然实验,基于2009—2022年全国257个地级及以上城市的面板数据,通过多期双重差分法考察数据要素集聚对地方财政韧性的作用效果及其异质... 为探究数据要素的价值创造与经济潜力对地方财政韧性的作用与机制,以国家级大数据综合试验区作为准自然实验,基于2009—2022年全国257个地级及以上城市的面板数据,通过多期双重差分法考察数据要素集聚对地方财政韧性的作用效果及其异质性。研究发现,数据要素集聚显著增强了地方财政韧性,该作用主要通过提升地方税收能力和人工智能水平实现。特别是对于大城市、数字基础设施水平较高以及财政支出分权程度较低的地区,数据要素对财政韧性的促进作用更显著。进一步的动态效应分析表明,数据要素集聚对财政韧性的影响效应具有逐渐减弱的趋势。因此,地方政府要深度释放数据要素红利,将其加快转化为税收增长点,同时针对数据要素的“高地”“洼地”差异化施策,借助数据要素赋能地方财政数字化转型。 展开更多
关键词 数据要素 财政韧性 国家级大数据综合试验区 税收能力
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我国区域再生水循环利用的发展现状及对策建议
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作者 孙丽娟 巫寅虎 +4 位作者 陈卓 聂春雷 李晓萍 杨春丽 胡洪营 《人民黄河》 北大核心 2026年第3期102-106,共5页
在缺水地区,实施区域再生水循环利用可以实现水资源、水环境和水生态“三水共治”。通过对两批共38个再生水循环利用试点城市地理位置分布、水资源现状及再生水利用现状分析,结合对部分城市的调研,分析总结了目前区域再生水循环利用存... 在缺水地区,实施区域再生水循环利用可以实现水资源、水环境和水生态“三水共治”。通过对两批共38个再生水循环利用试点城市地理位置分布、水资源现状及再生水利用现状分析,结合对部分城市的调研,分析总结了目前区域再生水循环利用存在的问题及困难,并有针对性地提出了相应对策建议。结果表明:试点城市以北方黄河流域缺水城市为主,反映了这些区域对再生水利用需求的迫切性;中重度及极重度缺水城市共31个,水资源短缺严重制约了城市发展;大部分城市的再生水利用率在25%以下,有的甚至不足10%,且目前再生水利用以景观环境用水为主,再生水利用区域发展不均衡。通过总结目前区域再生水循环利用存在的问题,提出以下对策建议:完善再生水利用政策法规、标准体系;明确水权归属,制定合理的定价机制,健全长效运营机制;明确再生水在水资源配置中的地位,加强区域统筹协调管理;完善再生水利用考核机制和激励政策;健全再生水利用监管体系和安全保障措施;加强再生水利用设施建设,提高再生水利用水平。 展开更多
关键词 区域再生水循环利用 试点城市 现状问题 对策建议
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数字普惠金融赋能共同富裕的机制与效应研究——基于双重机器学习的方法
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作者 李文启 李玉璇 钟钰 《华南农业大学学报(社会科学版)》 北大核心 2026年第1期90-104,共15页
基于中国2012—2023年278个地级市面板数据,运用熵权法从发展性、共享性和可持续性三个维度测度共同富裕水平,并通过构造普惠金融改革试点政策变量,采用双重差分法(DID)和双重机器学习方法(DDML)进行实证分析。研究发现,该项试点政策显... 基于中国2012—2023年278个地级市面板数据,运用熵权法从发展性、共享性和可持续性三个维度测度共同富裕水平,并通过构造普惠金融改革试点政策变量,采用双重差分法(DID)和双重机器学习方法(DDML)进行实证分析。研究发现,该项试点政策显著促进本地区的共同富裕水平,对共同富裕的发展性、共享性和可持续性均具有积极影响,且在共享性维度的提升效果最为显著。作用机制检验表明,普惠金融改革通过提升企业创业活跃度、资金流通效率和资本市场一体化促进共同富裕的实现。异质性分析发现,在经济发展水平高和数字基础高的城市,普惠金融改革对共同富裕的促进效果更为显著;在普惠金融改革政策影响下教育资源投入、金融服务能力与共同富裕呈“倒U型”关系。进一步分析发现,“宽带中国”战略与普惠金融改革政策的协同实施对共同富裕具有更显著的促进作用。研究为深入理解普惠金融改革在促进共同富裕中的作用提供实证依据,对推动经济高质量发展和实现共同富裕具有重要意义。 展开更多
关键词 普惠金融改革 共同富裕 双重机器学习 双重差分法 “双试点”政策
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基于多模态分解信息的新能源场站送出线路纵联保护新判据
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作者 李振兴 杨桄 +3 位作者 王莉 胡聪 翁汉琍 李培阳 《电力系统保护与控制》 北大核心 2026年第3期22-34,共13页
针对新能源场站送出线路故障时因短路电流受限及频率偏移导致的传统保护性能下降问题,提出一种新型纵联保护判据,该判据基于经验模态分解(empirical mode decomposition,EMD)提取本征模态函数分量(intrinsic mode functions,IMF),并利用... 针对新能源场站送出线路故障时因短路电流受限及频率偏移导致的传统保护性能下降问题,提出一种新型纵联保护判据,该判据基于经验模态分解(empirical mode decomposition,EMD)提取本征模态函数分量(intrinsic mode functions,IMF),并利用Kendall相关系数进行故障识别。首先分析了传统纵联保护与现有相似度算法的适用性。在此基础上,对线路两端故障电流进行经验模态分解,并利用Kendall相关系数分析其分解信息的相似度,以揭示其中蕴含的故障特征。其次,深入分析区内外故障时各阶IMF分量Kendall系数的差异,据此评估不同分量的故障表征能力。最终,通过赋予各分量差异化权重,构建一个融合电流幅值、相位及极性特征的综合相似度保护判据。仿真结果表明,该方法能够不受新能源故障电流特性的影响,正确判别新能源场站多种故障场景下区内外短路故障,具有动作时间短、准确性高、适应性强的优势。 展开更多
关键词 新能源场站 送出线路 经验模态分解 Kendall相关系数 综合相似度值 纵联保护
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自由贸易试验区建设、制度改善与企业供应链效率——以企业存货管理为视角
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作者 张晓涛 李建生 钟腾龙 《厦门大学学报(哲学社会科学版)》 北大核心 2026年第1期26-39,共14页
在全球产业链供应链不稳定性加剧的情形下,制度环境对于提升供应链效率,保障供应链安全的重要性日益凸显。基于企业供应链的微观视角,采用2010—2019年期间上市企业数据和多期双重差分方法,研究自由贸易试验区建设如何提升企业存货管理... 在全球产业链供应链不稳定性加剧的情形下,制度环境对于提升供应链效率,保障供应链安全的重要性日益凸显。基于企业供应链的微观视角,采用2010—2019年期间上市企业数据和多期双重差分方法,研究自由贸易试验区建设如何提升企业存货管理效率。研究发现:自贸试验区建设明显提升了片区内企业的存货管理效率,体现为存货水平不变但存货周转率明显增加。机制分析表明,自贸试验区建设通过企业出口带动效应与扩链和稳链效应来提升片区内企业的存货管理效率。调节机制分析表明:管委会行政地位越高,自贸试验区建设所带来的企业存货管理效率提升效应越大;以两业融合为产业导向的自贸试验区,其自贸区建设也会引致企业存货管理效率的显著提升。异质性分析表明,这种影响对自贸试验区前身为国家级新区的企业、民营企业以及未进行信息共享的企业存货管理效率提升作用更大。 展开更多
关键词 自由贸易试验区 制度环境 存货管理 供应链效率
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