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Shape Analysis of Agricultural Parcels for Land Consolidation Priorities in Tekirdag Province,Turkey 被引量:1
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作者 Bahadir ALTURK 《Chinese Geographical Science》 SCIE CSCD 2024年第1期93-105,共13页
Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significan... Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significantly to spatial prioritization where there is also a high probability of achieving positive effects of consolidation projects.This study aims to determine the shape degree of the agricultural parcels both at singular and rural county scales in Tekirdag Province,Turkey in 2020 by combining the parcel shape index(PSI) with the minimum bounding geometry index(MBG) to improve parcel scores.Hot-spot zones of the highly irregular and near optimum parcels were also determined using Getis-Ord G_(i)^(*) statistic.The parcel degrees were classified into four categories,namely highly irregular,irregular,regular and near optimum.The obtained unweighted scores of the parameters exhibit deviations from the expected values.After weighting by pairwise comparison,the values approached ideal scores.Among 346 740 parcels,53% were highly irregular and irregular and 47% were regular and near optimum shapes after weighting whereas these were 70% and 30%,respectively before weighting.The average parcel degree of 63 rural counties was regular while the average parcel degree of the remaining 264 rural counties was irregular.The combined use of PSI and MBG index improved the correctness of the parcel shape score.It could be suggested to use as a tool in land consolidation prioritization. 展开更多
关键词 land consolidation priority parcel shape index(PSI) minimum bounding geometry(MBG) sustainable rural development hot-spot analysis Tekirdag Province TURKEY
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YOLO-Based Damage Detection with StyleGAN3 Data Augmentation for Parcel Information-Recognition System
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作者 Seolhee Kim Sang-Duck Lee 《Computers, Materials & Continua》 SCIE EI 2024年第7期195-215,共21页
Damage to parcels reduces customer satisfactionwith delivery services and increases return-logistics costs.This can be prevented by detecting and addressing the damage before the parcels reach the customer.Consequentl... Damage to parcels reduces customer satisfactionwith delivery services and increases return-logistics costs.This can be prevented by detecting and addressing the damage before the parcels reach the customer.Consequently,various studies have been conducted on deep learning techniques related to the detection of parcel damage.This study proposes a deep learning-based damage detectionmethod for various types of parcels.Themethod is intended to be part of a parcel information-recognition systemthat identifies the volume and shipping information of parcels,and determines whether they are damaged;this method is intended for use in the actual parcel-transportation process.For this purpose,1)the study acquired image data in an environment simulating the actual parcel-transportation process,and 2)the training dataset was expanded based on StyleGAN3 with adaptive discriminator augmentation.Additionally,3)a preliminary distinction was made between the appearance of parcels and their damage status to enhance the performance of the parcel damage detection model and analyze the causes of parcel damage.Finally,using the dataset constructed based on the proposed method,a damage type detection model was trained,and its mean average precision was confirmed.This model can improve customer satisfaction and reduce return costs for parcel delivery companies. 展开更多
关键词 parcel delivery service damage detection damage classification data augmentation generative adversarial network
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高性能并行PIM系统中Parcels通信机制研究
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作者 温璞 杨学军 唐玉华 《小型微型计算机系统》 CSCD 北大核心 2006年第3期554-557,共4页
基于Processor-in-Memory(PIM)技术的高性能并行系统具有可扩展性、自适应性、鲁棒性和低功耗等特性.借助于Parcels通信机制,并行PIM系统可以实现消息驱动的计算,重叠计算与通信,降低通信系统对细粒度并行应用的影响,可充分利用PIM的内... 基于Processor-in-Memory(PIM)技术的高性能并行系统具有可扩展性、自适应性、鲁棒性和低功耗等特性.借助于Parcels通信机制,并行PIM系统可以实现消息驱动的计算,重叠计算与通信,降低通信系统对细粒度并行应用的影响,可充分利用PIM的内部带宽和应用局部性.文章对并行PIM系统中采用的Parcels通信机制及其特点、Parcels通信模型,以及Parcels的典型应用系统进行了着重介绍,对存在的问题进行了分析并指出了进一步的研究方向. 展开更多
关键词 Processor-in-Memory parcels通信机制 用户层通信 并行系统
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Joint Multi-modal Parcellation of the Human Striatum:Functions and Clinical Relevance 被引量:1
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作者 Xiaojin Liu Simon B.Eickhoff +14 位作者 Felix Hoffstaedter Sarah Genon Svenja Caspers Kathrin Reetz Imis Dogan Claudia R.Eickhoff Ji Chen Julian Caspers Niels Reuter Christian Mathys Andre Aleman Renaud Jardri Valentin Riedl Iris E.Sommer Kaustubh R.Patil 《Neuroscience Bulletin》 SCIE CAS CSCD 2020年第10期1123-1136,共14页
The human striatum is essential for both lowand high-level functions and has been implicated in the pathophysiology of various prevalent disorders,including Parkinson's disease(PD)and schizophrenia(SCZ).It is know... The human striatum is essential for both lowand high-level functions and has been implicated in the pathophysiology of various prevalent disorders,including Parkinson's disease(PD)and schizophrenia(SCZ).It is known to consist of structurally and functionally divergent subdivisions.However,previous parcellations are based on a single neuroimaging modality,leaving the extent of the multi-modal organization of the striatum unknown.Here,we investigated the organization of the striatum across three modalities—resting-state functional connectivity,probabilistic diffusion tractography,and structural covariance—to provide a holistic convergent view of its structure and function.We found convergent clusters in the dorsal,dorsolateral,rostral,ventral,and caudal striatum.Functional characterization revealed the anterior striatum to be mainly associated with cognitive and emotional functions,while the caudal striatum was related to action execution.Interestingly,significant structural atrophy in the rostral and ventral striatum was common to both PD and SCZ,but atrophy in the dorsolateral striatum was specifically attributable to PD.Our study revealed a cross-modal convergent organization of the striatum,representing a fundamental topographical model that can be useful for investigating structural and functional variability in aging and in clinical conditions. 展开更多
关键词 STRIATUM MULTI-MODAL Connectivity-based parcellation Convergent clusters Voxel-based morphometry Parkinson's disease SCHIZOPHRENIA
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Feature-reduction and semi-simulated data in functional connectivity-based cortical parcellation
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作者 Xiaoguang Tian Cirong Liu +3 位作者 Tianzi Jiang Joshua Rizak Yuanye Ma Xintian Hu 《Neuroscience Bulletin》 SCIE CAS CSCD 2013年第3期333-347,共15页
Recently, restingstate functional magnetic resonance imaging has been used to parcellate the brain into functionally distinct regions based on the information available in functional connectivity maps. However, brain ... Recently, restingstate functional magnetic resonance imaging has been used to parcellate the brain into functionally distinct regions based on the information available in functional connectivity maps. However, brain voxels are not independent units and adjacent voxels are always highly correlated, so functional connectivity maps contain redundant information, which not only impairs the computational efficiency during clustering, but also reduces the accuracy of clustering results. The aim of this study was to propose featurereduction approaches to reduce the redundancy and to develop semisimulated data with defined ground truth to evaluate these approaches. We proposed a featurereduction approach based on the Affinity Propagation Algorithm (APA) and compared it with the classic feature reduction approach based on Principal Component Analysis (PCA). We tested the two approaches to the parcellation of both semisimulated and real seed regions using the Kmeans algorithm and designed two experiments to evaluate their noise resistance. We found that all functional connectivitymaps (with/without feature reduction) provided correct information for the parcellation of the semi simulated seed region and the computational efficiency was greatly improved by both feature reduction approaches. Meanwhile, the APAbased featurereduction approach outperformed the PCA based approach in noiseresistance. The results suggested that functional connectivity maps can provide correct information for cortical parcellation, and featurereduction does not significantly change the information. Considering the improvement in computational efficiency and the noiseresistance, featurereduction of functional connectivity maps before cortical parcellation is both feasible and necessary. 展开更多
关键词 cortical parcellation resting-state fMRI functional connectivity feature reduction stimulateddata AP algorithm
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On the Development of Meso-Scale Heavy Rain Parcels in China
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作者 章淹 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1995年第1期79-86,共8页
Heavy rains occur in China frequently, which often bring us floods and serious disasters in the summer half-year. The meso-scale heavy rain parcels (MHRP) in the mid-latitude are usually developed in following cases:I... Heavy rains occur in China frequently, which often bring us floods and serious disasters in the summer half-year. The meso-scale heavy rain parcels (MHRP) in the mid-latitude are usually developed in following cases:I.By the approaching, meeting and / or overlapping of different weather systems, when two or more different rainfall systems are getting to conjugate, some MHRPs could be developed, such as: 1) a new cold/warm front or squall line approaches an old front or squall, even when the old one is somewhat decrepit; 2) at the places where two or more synoptic systems with different characteristics are meeting together, such as the meeting of tropical cyclone with the cold airs coming from the mid- and / or high-latitudes, or the low latitude vortex meeting with the westerly trough; 3) at the intersections of some different weather systems, such as the intersection of drylines, squall lines or fronts moving from different directions; and 4) by the overlapping of rainfall parcels produced continuously from a meso-generation centre.II.Resonance Effect and Tibetan Plateau Influence are two reasons why high frequency of heavy and torrential rains arround the meiyu front is discussed also. 展开更多
关键词 Meso-scale heavy rain parcels (MHRP) Forcing field Interactions of different weather systems Resonance effect Tibetan Plateau influence.
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Abandoned land identification in karst mountain area based on time series SAR characteristics at geo-parcels scale
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作者 ZHOU Zhong-fa WANG Ling-yu +6 位作者 CHEN Quan LUO Jian-cheng ZHAO Xin ZHANG Shu ZHANG Wen-hui LIAO Juan LYU Zhi-jun 《Journal of Mountain Science》 SCIE CSCD 2023年第3期792-809,共18页
Mapping abandoned land is very important for accurate agricultural management.However,in karst mountainous areas,continuous high-resolution optical images are difficult to obtain in rainy weather,and the land is fragm... Mapping abandoned land is very important for accurate agricultural management.However,in karst mountainous areas,continuous high-resolution optical images are difficult to obtain in rainy weather,and the land is fragmented,which poses a great challenge for remote sensing monitoring of agriculture activities.In this study,a new method for identifying abandoned land is proposed:firstly,a few Google Earth images are used to transform arable land into accurate vectorized geo-parcels;secondly,a time-series data set was constructed using Sentinel-1A Alpha parameters for 2020 on each farmland geoparcel;thirdly,the semi-variation function(SVF)was used to analyze the spatial-temporal characteristics,then identify abandoned land.The results show:(1)On the basis of accurate spatial information and boundary of farmland land,the SAR time-series dataset reflects the structure and time-series response.abandoned land with an accuracy of 80.25%.The problem of remote sensing monitoring in rainy regions and complex surface areas is well-resolved.(2)The spatial heterogeneity of abandoned land is more obvious than that of cultivated land within geoparcels.The step size for significant changes in the SVF of abandoned land is shorter than that of cultivated land.(3)The SVF time sequence curve presented a strong peak feature when farmland was abandoned.This reveals that the internal spatial structure of abandoned land is more disordered and complex.It showed that time-series variations of spatial structure within cultivated land have broader applications in remote sensing monitoring of agriculture in complex imaging environments. 展开更多
关键词 Sentinel-1 SAR Abandoned farmland Semi variogram function Farmland geo parcel Time seriescharacteristics Texture feature Karst mountainous area
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Building a Geodatabase for Parcel and Cadaster Mapping and Add-Ins Development: A Case Study for Defense Housing Authority (DHA), Lahore, Pakistan
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作者 Mamoon Ur Rasheed Sajid Rashid Ahmad Rashid Saleem 《Journal of Geographic Information System》 2015年第6期588-597,共10页
This paper presents a systematic view of most up-to-date tools, technologies and techniques which is appropriate not only for effective decision making, but also helpful for competent administration to provide efficie... This paper presents a systematic view of most up-to-date tools, technologies and techniques which is appropriate not only for effective decision making, but also helpful for competent administration to provide efficient resolution for spatial troubles of Khasra and Parcel management. Different Data collection techniques have been applied on different data sources. Worldview II of 0.5 resolution image, scanned Master Plan and Cadastral/Khasra Maps was used for development of geodatabase for spatial and non-spatial entities using ArcGIS 10.2. Multiple processing on Satellite Imagery using ERDAS Imagine was performed like Image enhancement, Mosaicking and Color Balancing, Image Geo-referencing and Raster Cataloging. Development of Customize Graphical User Interface (GUI) for DHA’s officials and administrator makes efficient decision in society matters. This is the first spatial GUI, for DHA to plan and maintain society’s activities efficiently, in the form of ArcMap Add-Ins. These Add-Ins are written in C#.Net using ArcObjects APIs within MSVS 2012. 展开更多
关键词 Khasra parcel ARCMAP Add-Ins ARCOBJECTS GEODATABASE
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An Analysis of the Air Parcel Trajectories of Long-Range Transport at Shanghai
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作者 邵德民 张维 +3 位作者 沈爱华 陈雪琴 付哲民 何珍珍 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第3期346-350,共5页
1.INTRODUCTION Acid rain observations show that acid cloud water in Shanghai region appears not only
关键词 ACID An Analysis of the Air parcel Trajectories of Long-Range Transport at Shanghai
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Parcels Delivered in 2019 to Reach 60 Billion
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《China Today》 2019年第3期8-8,共1页
The State Post Bureau(SPB)predicts that the volume of parcels delivered this year will reach 60 billion,a 20 percent year-onyear growth.
关键词 parcels Delivered The STATE POST Bureau(SPB) GROWTH
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Alarm on Invasion of Harmful Organisms Via Postal Parcels
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作者 Wang Jiaying Cui Junxia Chen Xianfeng 《Plant Diseases and Pests》 CAS 2020年第2期28-30,34,共4页
In recent years,with the rapid development of cross-border e-commerce,international postal parcels have been increasing sharply,thus giving rise to a new way for alien biological invasion.According to the"animal ... In recent years,with the rapid development of cross-border e-commerce,international postal parcels have been increasing sharply,thus giving rise to a new way for alien biological invasion.According to the"animal and plant quarantine information platform"of the General Adminis-tration of Customs,postal inspection system intercepted a total of 4975 harmful organisms nationwide.There were 219 quarantine organisms,including 142 insects,27 weeds,12 nematodes,29 fungi,1 bacterium and 8 viruses.Insects accounted for 64.84%of the quarantine organisms,among which Hypothenemus hampei had the highest interception frequency.Up to 71.36%of those harmful organisms were from seedlings,yet47.31%organisms came from products exported from India.These analyses indicate the direction of future portal quarantine work and lay a theoret-ical foundation for better guarding the biological security. 展开更多
关键词 International postal parcels Postal quarantine system Biological invasion Gate biological security
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A Uniform Parcel Delivery System Based on IoT
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作者 Yuhui Wang Hongbo Zhu +2 位作者 Zechun Wang Haolong Li Guangyao Li 《Advances in Internet of Things》 2018年第4期39-63,共25页
Nowadays, many different kinds of delivery companies transport their own kinds of parcels and offer their own services, which have caused a lot waste of resources. In addition, the volume of parcels in all cities that... Nowadays, many different kinds of delivery companies transport their own kinds of parcels and offer their own services, which have caused a lot waste of resources. In addition, the volume of parcels in all cities that need to be delivered has been grown dramatically. To cope with these problems, a uniform parcel delivery system in a smart city which can offer service to all kinds of customers in the city including manufactures, department stores, restaurants, individual people and so forth was designed. This system uses IoT (Internet of Things) and RFID technology, combining computer network technology, wireless communication and cloud computing. With this system, the whole package delivery process including classification of packages, vehicle scheduling, path planning, transportation monitoring can be intellectualized as well as managed automatically, and the use of both material resources and manpower resources can be reduced accordingly. 展开更多
关键词 INTERNET of THINGS parcel Delivery System RFID GPS
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Connectivity-based Cortical Parcellation via Contrastive Learning on Spatial-Graph Convolution
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作者 Peiting You Xiang Li +1 位作者 Fan Zhang Quanzheng Li 《Biomedical Engineering Frontiers》 2022年第1期105-115,共11页
Objective.Objective of this work is the development and evaluation of a cortical parcellation framework based on tractography-derived brain structural connectivity.Impact Statement.The proposed framework utilizes nove... Objective.Objective of this work is the development and evaluation of a cortical parcellation framework based on tractography-derived brain structural connectivity.Impact Statement.The proposed framework utilizes novel spatial-graph representation learning methods for solving the task of cortical parcellation,an important medical image analysis and neuroscientific problem.Introduction.The concept of“connectional fingerprint”has motivated many investigations on the connectivity-based cortical parcellation,especially with the technical advancement of diffusion imaging.Previous studies on multiple brain regions have been conducted with promising results.However,performance and applicability of these models are limited by the relatively simple computational scheme and the lack of effective representation of brain imaging data.Methods.We propose the Spatial-graph Convolution Parcellation(SGCP)framework,a two-stage deep learning-based modeling for the graph representation brain imaging.In the first stage,SGCP learns an effective embedding of the input data through a self-supervised contrastive learning scheme with the backbone encoder of a spatial-graph convolution network.In the second stage,SGCP learns a supervised classifier to perform voxel-wise classification for parcellating the desired brain region.Results.SGCP is evaluated on the parcellation task for 5 brain regions in a 15-subject DWI dataset.Performance comparisons between SGCP,traditional parcellation methods,and other deep learning-based methods show that SGCP can achieve superior performance in all the cases.Conclusion.Consistent good performance of the proposed SGCP framework indicates its potential to be used as a general solution for investigating the regional/subregional composition of human brain based on one or more connectivity measurements. 展开更多
关键词 CONNECTIVITY parcel SPATIAL
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Sino-US Deal Parcels out Offshore Oil, Gas Rights
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《China Oil & Gas》 CAS 1997年第1期55-55,共1页
关键词 US Gas Rights Sino-US Deal parcels out Offshore Oil
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Summary of Animal and Plant Quarantine Objects in the Imported Parcels and X-ray Pattern Identification
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作者 Zhiling Cao 《Journal of Zoological Research》 2019年第2期26-27,共2页
The quantity of the imported parcels in China has increased rapidly,becoming an important means for criminals to hide the prohibited animal and plant quarantine objects.The x-ray applied to the port of post inspection... The quantity of the imported parcels in China has increased rapidly,becoming an important means for criminals to hide the prohibited animal and plant quarantine objects.The x-ray applied to the port of post inspection can speed up inspection and better protect the ecological safety of China by mastering its method of judging animal and plant quarantine objects. 展开更多
关键词 The Imported parcels Animal and plant quarantine X-RAY
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An end‐to‐end infant brain parcellation pipeline 被引量:1
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作者 Limei Wang Yue Sun +2 位作者 Weili Lin Gang Li Li Wang 《Intelligent Medicine》 EI CSCD 2024年第2期65-74,共10页
Objective Accurate infant brain parcellation is crucial for understanding early brain development;however,it is challenging due to the inherent low tissue contrast,high noise,and severe partial volume effects in infan... Objective Accurate infant brain parcellation is crucial for understanding early brain development;however,it is challenging due to the inherent low tissue contrast,high noise,and severe partial volume effects in infant magnetic resonance images(MRIs).The aim of this study was to develop an end-to-end pipeline that enabled accurate parcellation of infant brain MRIs.Methods We proposed an end-to-end pipeline that employs a two-stage global-to-local approach for accurate parcellation of infant brain MRIs.Specifically,in the global regions of interest(ROIs)localization stage,a combination of transformer and convolution operations was employed to capture both global spatial features and fine texture features,enabling an approximate localization of the ROIs across the whole brain.In the local ROIs refinement stage,leveraging the position priors from the first stage along with the raw MRIs,the boundaries of the ROIs are refined for a more accurate parcellation.Results We utilized the Dice ratio to evaluate the accuracy of parcellation results.Results on 263 subjects from National Database for Autism Research(NDAR),Baby Connectome Project(BCP)and Cross-site datasets demonstrated the better accuracy and robustness of our method than other competing methods.Conclusion Our end-to-end pipeline may be capable of accurately parcellating 6-month-old infant brain MRIs. 展开更多
关键词 Infant brain parcellation Isointense magnetic resonance image Convolutional neural networks TRANSFORMER
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A large-scale analytical residential parcel delivery model evaluating greenhouse gas emissions,COVID-19 impact,and cargo bikes
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作者 Hai Yang Hector Landes Joseph Y.J.Chow 《International Journal of Transportation Science and Technology》 2024年第3期136-154,共19页
The e-commerce industry has experienced significant growth in the past decade,particu-larly post-COVID.To accommodate such growth,the parcel delivery sector has also grown rapidly.However,there is a lack of study that... The e-commerce industry has experienced significant growth in the past decade,particu-larly post-COVID.To accommodate such growth,the parcel delivery sector has also grown rapidly.However,there is a lack of study that properly evaluates its social and environ-mental impacts at a large scale.A model is proposed to analyze such impacts.A parcel gen-eration process is presented to convert public data into parcel volumes and stops.A continuous approximation model is fitted to estimate the length of parcel service tours.A case study is conducted using New York City(NYC)data.The parcel generation is shown to be a valid fit.The continuous approximation model parameters have R2 values of 98%or higher.The model output is validated against UPS truck trips.Application of the model to 2021 suggests residential parcel deliveries contributed to 0.05%of total daily vehicle-kilometer-traveled(VKT)in NYC corresponding to 14.4 metric tons of carbon equivalent(MTCE)emissions per day.COVID-19 contributed to an increase in parcel deliveries that led to up to 1064.3 MTCE of annual greenhouse gas(GHG)emissions in NYC(which could power 532 standard US households for a year).The existing bike lane infrastructure can support the substitution of 17%of parcel deliveries by cargo bikes,which would reduce VKT by 11%.Adding 3 km of bike lanes to connect Amazon facilities can expand their cargo bike substitution benefit from a VKT reduction of 5%up to 30%.If 28 km of additional bike lanes are made,parcel delivery substitution citywide could increase from 17%to 34%via cargo bike and save an additional 2.3 MTCE per day.Cargo bike priorities can be set to reduce GHG emissions for lower-income neighborhoods including Harlem,Sunset Park,and Bushwick. 展开更多
关键词 Urban logistics parcel delivery Continuous approximation Greenhouse gas(GHG) Cargo bike
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耦合空间分布模式的复杂山区地块作物遥感分类方法
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作者 吴田军 李曼嘉 +4 位作者 骆剑承 李子琪 胡晓东 郜丽静 沈占锋 《测绘学报》 北大核心 2025年第7期1215-1229,共15页
地块级作物空间分布地图是精准农业应用的迫切需求。然而,在山区地形起伏、耕地结构破碎、作物类型多样、云雨天气频繁的环境条件下,现有仅依托遥感数据驱动的作物分类模型仍无法满足实际要求,究其原因是对山区农地系统复杂性、遥感成... 地块级作物空间分布地图是精准农业应用的迫切需求。然而,在山区地形起伏、耕地结构破碎、作物类型多样、云雨天气频繁的环境条件下,现有仅依托遥感数据驱动的作物分类模型仍无法满足实际要求,究其原因是对山区农地系统复杂性、遥感成像的不确定性及作物种植的时空唯一性缺乏深刻认知,对空间效应关联知识的深层次融入运用不足。对此,本文聚焦复杂地表作物遥感制图的不确定性分析问题,以地块为核心对象,在图谱协同分析框架下开展作物分类方法研究,旨在耦合空间分布模式建立作物种植空间场景解构、作物生长谱序特征重建、作物类型判别模型增强3个创新链环节。西南山地典型区域的综合试验揭示了引入空间分布模式对于不确定性消减的正向作用,明晰地块精细提取、先验知识约束、特征重组拓展、分类器强化等措施的联合对提升山区作物辨识力的促进意义。本文在理论上深化对复杂地表区作物遥感解译机制的探索,在实践上为农业保险、灾害评估等场景生成更高精度、更具解释性的作物类型图提供示范与技术支撑。 展开更多
关键词 地块 作物遥感分类 山区 图谱协同 空间分布模式
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先验知识融合语义特征的冬小麦田块精细提取方法 被引量:2
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作者 程傲 任子由 +5 位作者 张承明 李峰 吴门新 李红英 段金馈 刘一笑 《农业工程学报》 北大核心 2025年第4期164-174,共11页
精细的田块数据是现代农业的重要基础资料,该研究针对从高分辨率遥感影像中提取田块精细数据的需求,建立了一种先验知识融合语义特征的冬小麦田块精细提取方法(prior knowledge and semantic features integration-based farmland parce... 精细的田块数据是现代农业的重要基础资料,该研究针对从高分辨率遥感影像中提取田块精细数据的需求,建立了一种先验知识融合语义特征的冬小麦田块精细提取方法(prior knowledge and semantic features integration-based farmland parcel extraction methodology,PKFFPE),PKFFPE以遥感图像和相应的边缘图像作为输入,采用编码器-解码器结构进行特征提取,利用多尺度注意力模块捕获不同尺度的关键特征,使用SoftMax对图像进行初步分割;通过深入分析同一田块内颜色、纹理等特征的分布规律获取先验知识,利用先验知识建立后处理方法,对初分割结果进行优化,生成田块精细数据。选择河北省邯郸市馆陶县和山东省泰安市宁阳县作为试验区,用于验证PKFFPE方法在平原地区和丘陵地区的适用性;选择UNet、ErfNet、SegNet、EIGNet,以及面向对象分类的方法作为初分割的对比方法,选择条件随机场和形态学处理作为的后处理的对比方法开展对比试验。试验结果表明,PKFFPE方法在馆陶县、宁阳县结果的准确率(96.1%、93.2%)、精确率(90.6%、87.6%)、召回率(93.2%、90.6%)、和F1分数(91.9%,89.0%)均优于对比方法,证明了PKFFPE方法在从高分辨遥感影像中提取田块精细数据方面具有突出的优势,能够应用于科研和生产实践。 展开更多
关键词 遥感 分类 冬小麦 卷积神经网络 先验知识 田块
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基于SAM2多任务学习的山区地块模糊边界提取 被引量:1
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作者 黄启厅 凌玉荣 +6 位作者 谢国雪 杨绍锷 杨颖频 李海亮 梁存穗 何新洁 谢意 《南方农业学报》 北大核心 2025年第1期18-28,F0002,共12页
【目的】构建多任务模糊边界提取深度学习模型,解决模糊边界难提取及伪边界难消除的问题,为地块破碎地区的地块边界提取提供参考依据。【方法】以广西河池市宜州区为研究区,通过解译典型山区破碎遥感影像,建立模糊边界提取数据集,引入S... 【目的】构建多任务模糊边界提取深度学习模型,解决模糊边界难提取及伪边界难消除的问题,为地块破碎地区的地块边界提取提供参考依据。【方法】以广西河池市宜州区为研究区,通过解译典型山区破碎遥感影像,建立模糊边界提取数据集,引入SAM2视觉大模型及采用适配器Adapter微调优化其编码器,设计地块属性提取辅助任务,构建多任务模糊边界提取深度学习模型SAM2Xi,并通过对比试验证实该模型在山区地块破碎环境下的模糊边界提取效果。【结果】SAM2Xi模型在全局最佳阈值(ODS)和单图最佳阈值(OIS)上表现最佳,分别为0.663和0.672,显示出最高的边缘检测精度和适应性,但50%精度召回率(R50)略低于DexiNed模型。SAM2Xi模型结合语义信息与边缘特征,增强了模糊边界识别能力,在复杂场景下表现尤为出色;SAM2Xi模型在低对比度和复杂背景下仍然保持高精度,模糊边界区域的细节保留、连贯性和噪声抑制均优于其他模型;此外,SAM2Xi模型在伪边界清除任务中表现最佳,其先进特征提取和优化机制几乎完全消除了伪边界干扰,在各类场景下保持高精度边缘检测,具有更高的鲁棒性和准确性。SAM2Xi模型能成功提取研究区的地块信息(地块图斑数1587597个,总面积145696.646 ha),且提取的地块分布与实际情况高度吻合,具体表现为:(1)在大片耕地范围内可准确划分各地块;(2)可提取建筑物中的零星耕地或园地;(3)可提取林地中能被单独分割的地块(人工林),但自然林基本不会被误识。【结论】基于SAM2多任务学习构建的SAM2Xi模型实现了模糊边界识别与伪边界清除的双重突破,在复杂地形适应性、边界连贯性保持及噪声抑制方面具有明显优势,为我国西南山区复杂地形下地块边界提取及山区农业资源精准管理提供了技术支撑。 展开更多
关键词 地块边界提取 SAM2 多任务学习 遥感影像 SAM2Xi模型
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