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Priority-Based Real-Time Stream Coding over Multi-Channel with Packet Erasures
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作者 Yunkai Wei Qianyu Liu +1 位作者 Zhoucha Hu Yuming Mao 《China Communications》 SCIE CSCD 2017年第1期72-85,共14页
Multi-channel can be used to provide higher transmission ability to the bandwidth-intensive and delay-sensitive real-time streams. However, traditional channel capacity theories and coding schemes are seldom designed ... Multi-channel can be used to provide higher transmission ability to the bandwidth-intensive and delay-sensitive real-time streams. However, traditional channel capacity theories and coding schemes are seldom designed for the real-time streams with strict delay constraint, especially in multi-channel context. This paper considers a real-time stream system, where real-time messages with different importance should be transmitted through several packet erasure channels, and be decoded by the receiver within a fixed delay. Based on window erasure channels and i.i.d.(identically and independently distributed) erasure channels, we derive the Multi-channel Real-time Stream Transmission(MRST) capacity models for Symmetric Real-time(SR) streams and Asymmetric Real-time(AR) streams respectively. Moreover, for window erasures, a Maximum Equilibrium Intra-session Code(MEIC) is presented for SR and AR streams, and is shown able to asymptotically achieve the theoretical MRST capacity. For i.i.d. erasures, we propose an Adaptive Maximum Equilibrium Intra-session Code(AMEIC), and then prove AMEIC can closely approach the MRST transmission capacity. Finally, the performances of the proposed codes are verified by simulations. 展开更多
关键词 real-time stream multi-channel channel coding erasure model transmission capacity
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MODELING OF THE PRIORITY SCHEDULING INPUT-LINE GROUP OUTPUT WITH MULTI-CHANNEL IN ATM EXCHANGE SYSTEM
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作者 Lu Zhaoyi Lv Lei Lu Mai 《Journal of Electronics(China)》 2006年第3期404-409,共6页
In this paper, an extended Kendall model for the priority scheduling input-line group output with multi-channel in Asynchronous Transfer Mode (ATM) exchange system is proposed and then the mean method is used to mod... In this paper, an extended Kendall model for the priority scheduling input-line group output with multi-channel in Asynchronous Transfer Mode (ATM) exchange system is proposed and then the mean method is used to model mathematically the non-typical non-anticipative PRiority service (PR) model. Compared with the typical and non-anticipative PR model, it expresses the characteristics of the priority scheduling input-line group output with multi-channel in ATM exchange system. The simulation experiment shows that this model can improve the HOL block and the performance of input-queued ATM switch network dramatically. This model has a better developing prospect in ATM exchange system. 展开更多
关键词 Asynchronous Transfer Mode (ATM) network priority Modeling research
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Accuracy allocation method for five-axis machine tools based on geometric error cost sensitivity prioritizing tool direction deviation 被引量:1
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作者 Xiaojian LIU Ao JIAO +7 位作者 Yang WANG Guodong YI Xiangyu GAO Xiaochen ZHANG Yiming ZHANG Yangjian JI Shuyou ZHANG Jianrong TAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第7期635-651,共17页
Accuracy allocation is crucial in the accuracy design of machining tools.Current accuracy allocation methods primarily focus on positional deviation,with little consideration for tool direction deviation.To address th... Accuracy allocation is crucial in the accuracy design of machining tools.Current accuracy allocation methods primarily focus on positional deviation,with little consideration for tool direction deviation.To address this issue,we propose a geometric error cost sensitivity-based accuracy allocation method for five-axis machine tools.A geometric error model consisting of 4l error components is constructed based on homogeneous transformation matrices.Volumetric points with positional and tool direction deviations are randomly sampled to evaluate the accuracy of the machine tool.The sensitivity of each error component at these sampling points is analyzed using the Sobol method.To balance the needs of geometric precision and manufacturing cost,a geometric error cost sensitivity function is developed to estimate the required cost.By allocating error components affecting tool direction deviation first and the remaining components second,this allocation scheme ensures that both deviations meet the requirements.We also perform numerical simulation of a BC-type(B-axis and C-axis type)five-axis machine tool to validate the method.The results show that the new allocation scheme reduces the total geometric error cost by 27.8%compared to a uniform allocation scheme,and yields the same positional and tool direction machining accuracies. 展开更多
关键词 Five-axis machine tool Accuracy allocation Geometric error modeling Error cost sensitivity Tool direction deviation priority
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Dynamic terahertz multi-channel beam steering with dual-frequency multiplexing based on magneto-optical metasurfaces
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作者 Dan Zhao Fei Fan +5 位作者 Hao Wang Pengxuan Li Zhen Xu Jining Li Yunyun Ji Shengjiang Chang 《Advanced Photonics Nexus》 2025年第3期149-157,共9页
With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A mag... With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A magnetic phase-coding meta-atom(MPM)is formed by the heterogeneous integration of La:YIG magneto-optical(MO)materials and Si microstructures.The MPM couples the magnetic induction phase of spin states with the propagation phase and can simultaneously satisfy the required output phase for dual frequencies under various external magnetic fields to realize the dynamic beam steering among multiple channels at 0.25 and 0.5 THz.The energy ratio of the target direction can reach 96.5%,and the nonreciprocal one-way transmission with a max isolation of 29.8 dB is realized due to the nonreciprocal phase shift of the MO layer.This nonreciprocal mechanism of magnetic induction reshaping of wavefront significantly holds promise for advancing integrated multi-functional THz devices with the characteristics of low-crosstalk,multi-channel,and multi-frequency,and has great potential to promote the development of THz large-capacity and high-speed communication. 展开更多
关键词 TERAHERTZ multi-channel DUAL-FREQUENCY nonreciprocal transmission beam steering dynamics
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AMSA:Adaptive Multi-Channel Image Sentiment Analysis Network with Focal Loss
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作者 Xiaofang Jin Yiran Li Yuying Yang 《Computers, Materials & Continua》 2025年第12期5309-5326,共18页
Given the importance of sentiment analysis in diverse environments,various methods are used for image sentiment analysis,including contextual sentiment analysis that utilizes character and scene relationships.However,... Given the importance of sentiment analysis in diverse environments,various methods are used for image sentiment analysis,including contextual sentiment analysis that utilizes character and scene relationships.However,most existing works employ character faces in conjunction with context,yet lack the capacity to analyze the emotions of characters in unconstrained environments,such as when their faces are obscured or blurred.Accordingly,this article presents the Adaptive Multi-Channel Sentiment Analysis Network(AMSA),a contextual image sentiment analysis framework,which consists of three channels:body,face,and context.AMSA employs Multi-task Cascaded Convolutional Networks(MTCNN)to detect faces within body frames;if detected,facial features are extracted and fused with body and context information for emotion recognition.If not,the model leverages body and context features alone.Meanwhile,to address class imbalance in the EMOTIC dataset,Focal Loss is introduced to improve classification performance,especially for minority emotion categories.Experimental results have shown that certain sentiment categories with lower representation in the dataset demonstrate leading classification accuracy,the AMSA yields a 2.53%increase compared with state-of-the-art methods. 展开更多
关键词 Image sentiment analysis adaptive multi-channel class imbalance
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Conservation Priorities for Lizard Biodiversity in the Qinghai-Xizang Plateau Under Climate Change:Current Status and Future Strategies
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作者 Tong LIU Xiaolong ZHAO +3 位作者 Jinyan YANG Yiqiong CUI Min CHEN Zhigao ZENG 《Asian Herpetological Research》 2025年第2期210-226,共17页
Global framework for nature management requires identifying areas of high priority for biodiversity conservation and restoration.The unique environments of Qinghai-Xizang Plateau(QXP) provide irreplaceable habitats fo... Global framework for nature management requires identifying areas of high priority for biodiversity conservation and restoration.The unique environments of Qinghai-Xizang Plateau(QXP) provide irreplaceable habitats for biodiversity which is prominent under future climate change.Despite the recent increase in research interest on conservation priorities,there is a lack of comprehensive and targeted protection strategies for pandemic species under climate change.Here,we compiled an exhaustive dataset with the variables of extinction risk and occurrence records of ectothermic lizards to investigate the conservation priorities in the QXP.We assessed the conservation status of the QXP lizards and identified the priority protected areas within the QXP under future climate scenarios using phylogenetic generalized least squares and ensemble species distribution models.Our analyses suggested nine lizard species to be prioritized for protection,with the most critical priority species being Dopasia gracilis,D.harti,and Phrynocephalus putjatai.Moreover,the priority protected areas covered~4.7%area of the QXP,mostly in the southern QXP and southeastern Hengduan Mountains.Protecting these regions would achieve a conservation effectiveness of≥95%for species richness,phylogenetic and functionaldiversity under climate change.Our findings provide realistic guidance for improving the conservation effectiveness of specific-lizard and-regions in the QXP under climate change.Our“bottom-up”approach could help the conservation efforts of other regions and species as an alternative to“top-down”global maps. 展开更多
关键词 climate change conservation priorities LIZARDS multidimensional biodiversity Qinghai-Xizang Plateau
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Multi-Channel Electrolyte Supply for Electrochemical Trepanning of Blisks Using Rotational Feeding Combined with Shift Feeding
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作者 Gaopan Lei Dong Zhu +3 位作者 Mingzhu Ren Erhao Jiao Yongquan Xie Mingfu Li 《Chinese Journal of Mechanical Engineering》 2025年第2期440-458,共19页
Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex ... Rotational feeding combined with shift feeding electrochemical trepanning(RF-SF ECTr)is an effective method for machining aeroengine blisks.However,given the variable relative motion of the electrodes and the complex flow channels around the bending and twisting blades,the accessibility and uniformity of the flow field are poor in blisk RF-SF ECTr using the traditional electrolyte supply(TES)mode,resulting in poor machining stability and low machining efficiency.To improve the distribution of the flow field,a new multi-channel electrolyte supply(MCES)mode is proposed for blisk RF-SF ECTr,in which the position and volume of the electrolyte supply are controlled effectively by setting multiple inlet channels in the liquid inlet area.A flow-field simulation comparison between TES and MCES shows that better accessibility and uniformity of the flow-field distribution are achieved under MCES.To clarify further the flow-field distribution characteristics under RF-SF ECTr,a series of flow-field simulations was conducted at different machining depths.Based on the obtained dynamic change law for the flow field,to enhance further its uniformity and accessibility,a global coverage strategy for the electrolyte supply and a flow-field structure optimization method for MCES are proposed,which involve optimizing the number,diameter,and location of the inlet channels.After many simulations,the optimal MCES structure was achieved whereby the electrolyte covers all positions effectively in the processing area.To verify the proposed method as effective and correct,a series of RF-SF ECTr experiments was carried out.Under the optimized MCES mode,the feeding rate was increased from 0.8 mm/min with the TES mode to 2.0 mm/min,and the processing stability and efficiency were improved significantly.The methods presented here offer an effective guide for flow-field optimization when machining other components with complex spatial structures. 展开更多
关键词 Electrochemical trepanning Blisk Rotational feeding Flow field optimization multi-channel electrolyte supply
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Integrated spatial priority assessment in Central Asia:Bridging biodiversity,ecosystem services,and human activities
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作者 Shiran Song Xi Chen +4 位作者 Chanjuan Zan Hao Zhang Chuan Wang Zengyun Hu Yaoming Li 《Geography and Sustainability》 2025年第2期194-208,共15页
Central Asia(CA)faces escalating threats from increasing temperature,glacier retreat,biodiversity loss,unsustainable water use,terminal lake shrinkage,and soil salinization,all of which challenge the balance between e... Central Asia(CA)faces escalating threats from increasing temperature,glacier retreat,biodiversity loss,unsustainable water use,terminal lake shrinkage,and soil salinization,all of which challenge the balance between ecological integrity and socio-economic development essential for achieving Sustainable Development Goals.However,a comprehensive understanding of priority areas from a multi-dimensional perspective is lacking,hindering effective conservation and development strategies.To address this,we developed a comprehensive assessment framework with a tailored indicator system,enabling a spatial evaluation of CA’s priority areas by integrating biodiversity,ecosystem services(ESs),and human activities.Combining zonation and geographical detectors,this approach facilitates spatial prioritization and examines ecological and socio-economic heterogeneity.Our findings reveal a heterogeneous distribution of priority areas across CA,with significant concentrations in eastern mountainous regions,river valleys,and oasis agricultural lands.We identified 184 key districts crucial for ecological and societal sustainability.Attribution analysis shows that natural factors like soil types,precipitation,and evapotranspiration significantly shape these areas,influencing human activities and the distribution of biodiversity and ESs.Multi-dimensional analysis indicates existing protected areas cover only 15%of the top 30%priority areas,revealing substantial conservation gaps.Additionally,a 38%overlap between ESs and human activities,along with 63.25%congruence in integrated areas,underscores significant human impacts on ecological systems and their dependency on ESs.Given CA’s limited resources,it is crucial to implement measures that strengthen conservation efforts,align ecological preservation with socio-economic demands,and enhance resource efficiency through sustainable integrated land and water resource management. 展开更多
关键词 Spatially priority assessment BIODIVERSITY Ecosystem services Human activities Central Asia
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Terahertz active multi-channel vortices with parity symmetry breaking and near/far field multiplexing based on a dielectric-liquid crystal-plasmonic metadevice
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作者 Yiming Wang Fei Fan +3 位作者 Huijun Zhao Yunyun Ji Jing Liu Shengjiang Chang 《Opto-Electronic Advances》 2025年第5期48-58,共11页
Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic v... Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic vortices(PVs)on chips,and active manipulation as well as multiplexing in more channels have become a pressing demand.In this work,we demonstrate a terahertz(THz)cascaded metadevice composed of a helical plasmonic metasurface,a liquid crystal(LC)layer,and a helical dielectric metasurface.By spin-orbital angular momentum coupling and photon state superposition,PVs and FVs are generated with mode purity of over 85%on average.Due to the inversion asymmetric design of the helical metasurfaces,the parity symmetry breaking of OAM is realized(the topological charge numbers no longer occur in positive and negative pairs,but all are positive),generating 6 independent channels associated with the decoupled spin states and the near-/far-field positions.Moreover,by the LC integration,dynamic mode switching and energy distribution can be realized,finally obtaining up to 12 modes with a modulation ratio of above 70%.This active tuning and multi-channel multiplexing metadevice establishes a bridge connection between the PVs and FVs,exhibiting promising applications in THz communication,intelligent perception,and information processing. 展开更多
关键词 TERAHERTZ optical vortex plasmonic metasurface near/far field multi-channel liquid crystal
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Analysis of the effect of multi-channel continuous nursing intervention on patients post-radical gastrectomy
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作者 Huan-Li Luo Huan-Ling Luo 《World Journal of Gastrointestinal Surgery》 2025年第4期110-119,共10页
BACKGROUND Radical gastrectomy(RGE)for gastric carcinoma(GC)has exerted definite therapeutic efficacy in treating patients with GC.However,a notable risk of postoperative complications(POCs)persists among middle-aged ... BACKGROUND Radical gastrectomy(RGE)for gastric carcinoma(GC)has exerted definite therapeutic efficacy in treating patients with GC.However,a notable risk of postoperative complications(POCs)persists among middle-aged and elderly patients with compromised physiological functions.Hence,developing and implementing reliable nursing interventions to optimize the comprehensive management of these patients is deemed imperative.AIM To analyze the association of multi-channel continuous nursing intervention with POCs,negative emotions(NEs),and quality of life(QoL)of patients undergoing RGE for GC.METHODS This retrospective study selected 99 patients who underwent RGE for GC in our hospital from May 2020 to May 2023.Participants were categorized into the control(n=49 cases)and research groups(n=50 cases)receiving routine and multi-channel continuous nursing care,respectively.Comparative analysis involved data on postoperative rehabilitation(time to first anal exhaust,oral feeding and ambulation,and hospital stay),complications(nausea and vomiting,delayed gastric emptying,and abdominal distension),NEs[Self-rating Anxiety(SAS)/Depression Scale(SDS)],treatment compliance,self-efficacy,and QoL[World Health Organization QoL Brief Version(WHOQOL-BREF)].RESULTS Compared to the control group,the research group demonstrated earlier first postoperative anal exhaust,oral feeding,and ambulation,shorter hospital stay,lower POC rate,and more reduced SAS and SDS scores postintervention,which was significantly lower than the baseline.The treatment compliance scores were significantly higher in the research group than in the control group in terms of medication adherence,daily exercise,reasonable diet,and regular review.Further,the research group demonstrated increased self-efficacy scores in terms of positive attitude,self-stress relief,and self-decision-making,as well as the overall score postintervention,which were higher than the control group.Moreover,the research group reported notably higher WHOQOL-BREF scores in domains such as physiology,psychology,social relations,and environment.CONCLUSION Multi-channel continuous nursing intervention prevents POCs in patients undergoing RGE for GC as well as significantly alleviates patients’NEs and boosts their QoL. 展开更多
关键词 Radical gastrectomy multi-channel continuous nursing Postoperative complications Negative emotions Quality of life
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A framework of the planning of priority revegetation areas for debris flow mitigation based on microclimate processes in dry-hot watersheds
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作者 LU Yafeng ZHOU Xiaokang 《Journal of Mountain Science》 2025年第5期1723-1733,共11页
Vegetation restoration is a critical strategy for mitigating debris flow hazards by stabilizing slopes and modifying hydrological processes.Effective planning of priority restoration areas is particularly essential in... Vegetation restoration is a critical strategy for mitigating debris flow hazards by stabilizing slopes and modifying hydrological processes.Effective planning of priority restoration areas is particularly essential in dry-hot valley regions,where extreme hydrothermal conditions pose significant challenges.This study presents a novel framework that integrates microclimatic variables,such as temperature lapse rates,to enhance the spatial precision of revegetation efforts.The Reshuihe watershed in Southwest China,a representative dry-hot valley,was chosen as the study area.By analyzing hourly temperature and rainfall across an elevation gradient,a quadratic relationship between temperature lapse rates and weak rainfall events was identified,underscoring the role of microclimatic processes in influencing rainfall distribution and plant-available water.Rainfall peaks were observed when the temperature lapse rate was approximately 4.5°C/km.This relationship was incorporated into a cost-based restoration framework using the Marxan model,optimizing the spatial allocation of priority areas for revegetation.Results demonstrated that integrating microclimatic variables significantly improved the effectiveness of revegetation strategies,particularly for reducing debris flow risks.The lowest restoration costs were observed between elevations of 3200 m and 3300 m,where strong correlations between temperature lapse rates and rainfall were recorded.Priority restoration areas covered 41 km^(2),targeting zones with high debris flow risks.These findings highlight the value of incorporating microclimatic data into revegetation planning,enabling cost-effective and ecologically sustainable hazard mitigation in regions vulnerable to hydrological hazards. 展开更多
关键词 REVEGETATION Microclimate processes Temperature lapse rate Dry-hot valley priority revegetation areas
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Post-pandemic mental health:Understanding the global psychological burden and charting future research priorities
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作者 Wei Ding Yuan Zhang +1 位作者 Min-Zhong Wang Shu Wang 《World Journal of Psychiatry》 2025年第10期67-86,共20页
The coronavirus disease 2019 pandemic has left an indelible mark on global mental health,with widespread psychological consequences that persist beyond the acute phase of the virus.This review synthesizes current evid... The coronavirus disease 2019 pandemic has left an indelible mark on global mental health,with widespread psychological consequences that persist beyond the acute phase of the virus.This review synthesizes current evidence on the postpandemic mental health burden across diverse populations,highlighting elevated rates of depression,anxiety,posttraumatic stress,and substance use disorders linked to prolonged social isolation,economic instability,and grief.We examine disparities in psychological outcomes among vulnerable groups(e.g.,healthcare workers,survivors,marginalized communities)and identify key challenges in addressing these issues,including fragmented healthcare systems,stigma,and the limited scalability of interventions.Emerging evidence on resilience factors(e.g.,social support and adaptive coping)is also discussed.Finally,we propose critical priorities for future research,including longitudinal studies on the chronic mental health effects,the development of culturally tailored interventions,and the integration of digital mental health solutions.This review distinctively addresses enduring post-pandemic mental health challenges,integrating neurobiological insights,equity-focused interventions,and critical perspectives on digital solutions,gaps underrepresented in prior syntheses.By charting a roadmap for multidisciplinary collaboration,this review aims to inform policymakers and researchers in mitigating the long-term psychological aftermath of the pandemic. 展开更多
关键词 COVID-19 Mental health Psychological burden Postpandemic Research priorities Global health
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Ecological restoration priority on the Qinghai-Xizang Plateau based on the nature’s contributions to people under SDGs-SSPs scenarios
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作者 Hua Liu Shiliang Liu +3 位作者 Fangfang Wang Yifei Zhao Yuhong Dong Lam-Son Phan Tran 《Geography and Sustainability》 2025年第5期101-115,共15页
Ecological restoration is considered an important way to mitigate ecosystem degradation and improve regional nature’s contributions to people(NCPs).Ecological planning is a prerequisite for ecological restoration and... Ecological restoration is considered an important way to mitigate ecosystem degradation and improve regional nature’s contributions to people(NCPs).Ecological planning is a prerequisite for ecological restoration and the prevention of future ecological risks.However,few studies have focused on integrating ecological plans within the framework of Sustainable Development Goals(SDGs)and shared socioeconomic pathways(SSPs).In this study,taking the Qinghai‒Xizang Plateau(QXP)as a case,we assessed ecological restoration priorities based on NCPs under various SDGs and SSP scenarios.Specifically,the land use demand was predicted using system dynamics(SD)and cellular automata(CA)models between 2030 and 2060 under SDG-SSP scenarios.In addition,habitat maintenance(NCP1),climate regulation(NCP4),and water quantity regulation(NCP6)were assessed based on the predicted land use.Finally,priority areas for ecological restoration were identified using a zonation model.The results indicated that the grassland,forest,and cultivated areas will increase in the SDGs and SSPs scenarios,respectively.The high-value NCP areas are mainly located in the southeast part of the QXP,accounting for 45.16%of the study area.In addition,the ecological restoration area involves grassland,cultivated and bare land.In the single-objective scenario,NCP1,NCP4,and NCP6 can be improved by 30.29%,28.75%and 25.63%,respectively,through the restoration of 15.33%of the priority areas identified in 2015.When shifting to a multi-objective cooperative optimum,NCP1,NCP4 and NCP6 can be improved 35.79%by restoring 54.96%of the priority areas.This study provides insight into how SDGs and SSPs can contribute to ecological restoration for mitigating ecosystem degradation under SDG-SSP scenarios. 展开更多
关键词 System dynamics Cellular automata Sustainable developmentgoals Nature’s contributionton people Shared socioeconomic pathways priority area
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What’s in a name for timber?Trade documentation and conservation prioritization in four tropical timber species imported to the United States
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作者 Mandira POKHAREL René Henri GERMAIN +2 位作者 John Eric WAGNER Susan Elizabeth ANAGNOST William Bradford SMITH 《Regional Sustainability》 2025年第5期1-18,共18页
The tropical timber trade faces significant sustainability challenges,including deforestation,illegal logging,and inadequate traceability.Inaccurate species identification further complicates these issues,leading to u... The tropical timber trade faces significant sustainability challenges,including deforestation,illegal logging,and inadequate traceability.Inaccurate species identification further complicates these issues,leading to unreliable trade statistics and enforcement challenges.The Lacey Act Amendment(LAA)of 2008 mandated declaring scientific names for timber shipments entering the United States.Therefore,this study assessed the implementation of the LAA using data obtained through a Freedom of Information Act request to the United States Department of Agriculture-Animal and Plant Health Inspection Service for 4 tropical timber species including Keruing,Meranti,Acajou d’Afrique,and Mahogany from Indonesia,Malaysia,Brazil,Philippines,Cameroon,Ghana,Congo,Cote d’Ivoire,and Bolivia,with high rates of illegal logging.This study showed that the United States imported 49 species of Keruing species group,126 species of Meranti species group,6 species of Acajou d’Afrique species group,and 2 species of Mahogany species group during 2017-2023.Despite mandatory declarations,approximately 14.60%of timber import records lacked species-specific names.Conservation assessments identified 37 species of Keruing species group and 68 species of Meranti species group listed as threatened by the International Union for Conservation of Nature(IUCN)but absent from the Convention on International Trade in Endangered Species of Wild Fauna and Flora(CITES).Moreover,the principal component analysis(PCA)indicated that the first principal component was primarily driven by import value and import volume,reflecting the overall trade prominence,while the second principal component captured temporal pattern through import year.Further,this study developed a Trade-Adjusted Conservation Priority Index(TACPI)that integrated conservation status with trade prominence to prioritize species at risk.Species with high TACPI scores,such as Dipterocarpus coriaceus and Shorea balangeran,were identified as urgently needing regulatory focus.To strengthen sustainable trade and conservation,it is recommended to enforce the LAA more strictly,expand timber identification technologies,and mandate key supplier countries,who are the CITES’signatories,to list high-risk species in the CITES appendices. 展开更多
关键词 Tropical timber trade Principal component analysis(PCA) Trade-Adjusted Conservation priority Index(TACPI) International Union for Conservation of Nature(IUCN) Convention on International Trade in Endangered Species of Wild Fauna and Flora(CITES)
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“十五五”背景下职业教育的认知重构与行动逻辑
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作者 姜大源 《中国职业技术教育》 北大核心 2026年第2期5-9,26,共6页
《关于制定国民经济和社会发展第十五个五年规划的建议》有三个值得职业教育充分关注的战略要点,即实体经济、技能人才、就业优先。这三个关键词正是新时代职业教育的发展方向。为此,职业教育要有所作为,就必须进行认知重构,采取行之有... 《关于制定国民经济和社会发展第十五个五年规划的建议》有三个值得职业教育充分关注的战略要点,即实体经济、技能人才、就业优先。这三个关键词正是新时代职业教育的发展方向。为此,职业教育要有所作为,就必须进行认知重构,采取行之有效的行动:一要为巩固壮大实体经济根基助力,二要为培养造就战略技能人才发力,三要为深入实施就业优先战略聚力,以不辱历史赋予职业教育的光荣使命。 展开更多
关键词 “十五五”规划 职业教育 实体经济 技能人才 就业优先
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远程医疗技术与医疗优先分级调派系统整合的效果评估:一项基于318名医疗相关人员调查的中期分析
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作者 梁永利 张培 胡翼南 《医学研究前沿》 2026年第1期136-138,共3页
目的基于318名医疗相关人员调查中期分析结果评估整合远程医疗技术与医疗优先分级调派系统(MPDS)的应用效果。方法本次研究对象为318名医疗人员及患者家属,采用自制调查问卷进行调查,分析研究对象对MPDS、远程医疗技术的认知情况、满意... 目的基于318名医疗相关人员调查中期分析结果评估整合远程医疗技术与医疗优先分级调派系统(MPDS)的应用效果。方法本次研究对象为318名医疗人员及患者家属,采用自制调查问卷进行调查,分析研究对象对MPDS、远程医疗技术的认知情况、满意度以及MPDS与远程医疗技术的整合预期。结果研究对象对MPDS总体认知度较高(61.95%),使用过MPDS的研究对象占比相对较低(43.08%)。大部分应用过MPDS的研究对象认为MPDS能够发挥积极作用且满意度较高。医疗相关人员及患者家属对远程医疗技术的认知度(61.64%)、接受度(91.19%)较高,绝大部分的研究对象认为整合远程医疗技术与MPDS能够提升急救效率(91.82%)。研究对象最为认可的预期优势为可视化指导更精准,构成比显著高于其他预期优势指标(P<0.05),其他各项预期优势指标构成比差异不具有统计学意义(P>0.05)。研究对象最为集中的期待功能为一键视频连通指导,构成比高于其他期待功能指标且差异具有统计学意义(P<0.05),其他各项期待功能构成比差异均具有统计学意义(P<0.05)。结论通过中期分析结果可知,MPDS与远程医疗技术系统整合受众基础广泛且有着较高的认可度与满意度。整合方案需要以提高操作简便性、保证技术普及型包以及实现核心功能为重点,从而能够有效应对复杂情况下患者信息不足的问题,可提高急救效率。 展开更多
关键词 远程医疗技术 医疗优先分级调派系统 急救效率 整合效果
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VVER-1200核电站安全级执行器驱动指令优先级研究
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作者 夏利民 王潇 +1 位作者 白玮 鲁超 《自动化仪表》 2026年第1期49-54,共6页
安全级执行器作为核电站重要的组成部分,需要在不同工况下执行不同的动作,以实现核电站的安全保护功能和控制功能。在核电站仪控系统设计时,需考虑来自不同的仪控系统/设备的安全级执行器驱动指令优先级方案,以实现安全级执行器的指令... 安全级执行器作为核电站重要的组成部分,需要在不同工况下执行不同的动作,以实现核电站的安全保护功能和控制功能。在核电站仪控系统设计时,需考虑来自不同的仪控系统/设备的安全级执行器驱动指令优先级方案,以实现安全级执行器的指令优先级处理和驱动功能。以水-水高能反应堆(VVER)-1200堆型核电站国产化平台的主仪控系统为基础,介绍了核电站安全级执行器驱动指令优先级设计原则和设计方法。进一步阐述了控制器、优先级设备以及电气开关盘等不同层级的优先级设计要求和目标。提出了适用于VVER-1200的优先级设计方案,并已成功应用于实际工程项目。该方案对于不同堆型核电站优先级控制方案设计和优先级驱动控制系统研发具有重要的借鉴意义。 展开更多
关键词 水-水高能反应堆 核电站 安全级 仪控系统 执行器 驱动指令 优先级
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多元主体视角下街道非机动交通路权研究
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作者 惠英 李伟江 +1 位作者 廖佳妹 郭佳怡 《城市交通》 2026年第1期13-23,共11页
在存量为主的城市发展阶段,落实非机动交通路权优先意味着对街道时空资源的再分配和路权关系的再调整,需统筹协调多元主体之间的复杂权益关系。融合产权、工程与经济社会学等多学科视角,界定了路权的内涵、主体与客体及其相互关系,将具... 在存量为主的城市发展阶段,落实非机动交通路权优先意味着对街道时空资源的再分配和路权关系的再调整,需统筹协调多元主体之间的复杂权益关系。融合产权、工程与经济社会学等多学科视角,界定了路权的内涵、主体与客体及其相互关系,将具体权益划分为过程权力和结果利益,从而构建了多元主体视角下的街道路权概念体系。针对实践中存在的管理权责分散、公众诉求表达不畅、更新动力机制不足等难点,研究归纳出单中心政府主导型、单中心政府引导型、在地机构支持型、多部门协作型4类路权调整模式。围绕空间、经济、文化3个维度构建评估指标体系,通过问卷调查评估了非机动交通视角下不同路权调整模式的效益差异。最后,从推动多元共治、探索适宜实施路径以及完善动力机制3个方面提出对策建议。 展开更多
关键词 非机动交通 路权优先 街道更新 多元主体 效益评估
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Development of multi-channel observation and inversion for IP electrical sounding method 被引量:8
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作者 刘海飞 柳建新 +3 位作者 郭荣文 童孝忠 龚露 彭艳华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期816-823,共8页
In order to improve the exploration effect of deep non-ferrous mineral resources, multi-channel observation methods for induced polarization (IP) electrical sounding data and their inversion imaging technology are s... In order to improve the exploration effect of deep non-ferrous mineral resources, multi-channel observation methods for induced polarization (IP) electrical sounding data and their inversion imaging technology are studied. First of all, four multi-channel observation methods are developed based on conventional IP electrical method, namely three-electrode and four-electrode arrays of unilateral and bilateral current transmitting. Then the maximum smoothness constrained inversion method of the least squares sense for IP electrical sounding data is proposed, and the inversion software is programmed. Finally, the simulation and inversion results of geo-electrical model for the proposed observation methods are analyzed. And the comparison results show that three-electrode array of bilateral current transmitting gives the best result, but the intensity in field work is larger than others; unilateral three-electrode and four-electrode arrays give the better results. Taking detection results and convenience of field exploration work into consideration, these two methods are more suitable for practical application; bilateral observation method of four-electrode array is not suitable for the detection of the steep ore bodies. 展开更多
关键词 IP electrica-1 sounding multi-channel observation deep exploration inversion imaging
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一种融合Priority-Flood算法与D8算法特点的河网提取方法 被引量:9
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作者 卢庆辉 熊礼阳 +2 位作者 蒋如乔 巫晓玲 段家朕 《地理与地理信息科学》 CSCD 北大核心 2017年第4期40-46,共7页
基于数字高程模型(Digital Elevation Models)进行河网提取是数字地形分析的重要研究内容和水文分析的关键步骤,而流向算法是其中最重要的部分。然而,传统的流向算法在平坦地形区域容易形成平行河网。为解决平行河网问题,该文提出了一... 基于数字高程模型(Digital Elevation Models)进行河网提取是数字地形分析的重要研究内容和水文分析的关键步骤,而流向算法是其中最重要的部分。然而,传统的流向算法在平坦地形区域容易形成平行河网。为解决平行河网问题,该文提出了一种结合Priority-Flood算法漫水思想和改进D8算法的流向算法。借助Priority-Flood算法的漫水思想,可以保证流向符合宏观地形特征;同时将地形划分为上坡、平地和下坡3种类型,辅以PriorityFlood算法可以实现在不填洼的基础上计算流向,而且针对不同地形,采用相应的改进D8流向算法,从而保证流向符合微观地形特征。通过这两种算法的结合,可以直接使用原始DEM提取河网,消除了填洼过程,提高了流向计算效率,同时消除了填洼造成的大量平地,有效地解决了平地区域平行河网问题。最后,选取全球不同区域SRTM数据对J&D算法与新算法进行对比实验,结果表明,新算法能够有效地改善平行河网问题。 展开更多
关键词 河网提取 priority2Flood算法 D8算法 平行河网 流向算法
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