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Three-dimensional localization of the individual shallow NV center in diamond using a gold tip
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作者 Jiarui Qi Xinghang Chen +1 位作者 Mengqi Wang Ya Wang 《中国科学技术大学学报》 北大核心 2025年第4期35-39,34,I0002,共7页
This work presents a method for the three-dimensional localization of individual shallow NV center in diamond,leveraging the near-field quenching effect of a gold tip.Our experimental setup involves the use of an atom... This work presents a method for the three-dimensional localization of individual shallow NV center in diamond,leveraging the near-field quenching effect of a gold tip.Our experimental setup involves the use of an atomic force microscope to precisely move the gold tip close to the NV center,while simultaneously employing a home-made confocal microscope to monitor the fluorescence of the NV center.This approach allows for lateral super-resolution,achieving a full width at half maximum(FWHM)of 38.0 nm and a location uncertainty of 0.7 nm.Additionally,we show the potential of this method for determining the depth of the NV centers.We also attempt to determine the depth of the NV centers in combination with finite-difference time-domain(FDTD)simulations.Compared to other depth determination methods,this approach allows for simultaneous lateral and longitudinal localization of individual NV centers,and holds promise for facilitating manipulation of the local environment surrounding the NV center. 展开更多
关键词 NV center super-resolution localization atom force microscopy
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Three-Dimensional Cooperative Localization via Space-Air-Ground Integrated Networks 被引量:2
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作者 Wenxuan Li Yuanpeng Liu +1 位作者 Xiaoxiang Li Yuan Shen 《China Communications》 SCIE CSCD 2022年第1期253-263,共11页
The space-air-ground integrated network(SAGIN)combines the superiority of the satellite,aerial,and ground communications,which is envisioned to provide high-precision positioning ability as well as seamless connectivi... The space-air-ground integrated network(SAGIN)combines the superiority of the satellite,aerial,and ground communications,which is envisioned to provide high-precision positioning ability as well as seamless connectivity in the 5G and Beyond 5G(B5G)systems.In this paper,we propose a three-dimensional SAGIN localization scheme for ground agents utilizing multi-source information from satellites,base stations and unmanned aerial vehicles(UAVs).Based on the designed scheme,we derive the positioning performance bound and establish a distributed maximum likelihood algorithm to jointly estimate the positions and clock offsets of ground agents.Simulation results demonstrate the validity of the SAGIN localization scheme and reveal the effects of the number of satellites,the number of base stations,the number of UAVs and clock noise on positioning performance. 展开更多
关键词 space-air-ground integrated network(SAGIN) three-dimensional(3D)localization clock noise multi-source information
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High-precision three-dimensional Rydberg atom localization in a four-level atomic system 被引量:1
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作者 Hengfei Zhang Jinpeng Yuan +2 位作者 Lirong Wang Liantuan Xiao Suo-tang Jia 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第5期348-352,共5页
Rydberg atoms have been widely investigated due to their large size,long radiative lifetime,huge polarizability and strong dipole-dipole interactions.The position information of Rydberg atoms provides more possibiliti... Rydberg atoms have been widely investigated due to their large size,long radiative lifetime,huge polarizability and strong dipole-dipole interactions.The position information of Rydberg atoms provides more possibilities for quantum optics research,which can be obtained under the localization method.We study the behavior of three-dimensional(3D)Rydberg atom localization in a four-level configuration with the measurement of the spatial optical absorption.The atomic localization precision depends strongly on the detuning and Rabi frequency of the involved laser fields.A 100%probability of finding the Rydberg atom at a specific 3D position is achieved with precision of~0.031λ.This work demonstrates the possibility for achieving the 3D atom localization of the Rydberg atom in the experiment. 展开更多
关键词 Rydberg atom three-dimensional localization standing-wave field
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Global Mapping of Three-Dimensional Urban Structures Reveals Escalating Utilization in the Vertical Dimension and Pronounced Building Space Inequality 被引量:1
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作者 Xiaoping Liu Xinxin Wu +6 位作者 Xuecao Li Xiaocong Xu Weilin Liao Limin Jiao Zhenzhong Zeng Guangzhao Chen Xia Li 《Engineering》 2025年第4期86-99,共14页
Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significan... Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies. 展开更多
关键词 three-dimensional Global mapping Building volume Building height Building space inequality
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Three-dimensional line-of-sight-angle-constrained leader-following cooperative interception guidance law with prespecified impact time 被引量:2
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作者 Hao YOU Xinlong CHANG Jiufen ZHAO 《Chinese Journal of Aeronautics》 2025年第1期491-506,共16页
To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D lea... To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance law.First,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact time.Next,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the time-to-go.Then,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy consumption.Moreover,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering applications.Finally,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law. 展开更多
关键词 three-dimensional cooperative interception Leader-following missiles Prespecified impact time LOS-angle-constrained Fixed-time stability Global integral sliding mode
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Clinical observation of gemcitabine and concomitant three-dimensional conformal radiotherapy in the treatment of locally advanced non-small cell lung cancer 被引量:4
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作者 Jing Cheng Gang Wu Hongge Wu Jun Xue 《The Chinese-German Journal of Clinical Oncology》 CAS 2008年第6期311-314,共4页
Objective: To evaluate the clinical effect of gemcitabine and concurrent three-dimensional conformal radiation therapy (3D-CRT) for locally advanced non-small cell lung cancer (NSCLC). Methods: From April 2002 t... Objective: To evaluate the clinical effect of gemcitabine and concurrent three-dimensional conformal radiation therapy (3D-CRT) for locally advanced non-small cell lung cancer (NSCLC). Methods: From April 2002 to June 2005, 38 patients with inoperable stage Ⅲ NSCLC were treated with gemcitabine and 3D-CRT simultaneously. Chemotherapy consisted of intravenously gemcitabine 350 mg/m^2 on days 1, 8, 15, 22, 29, 36.3D-CRT was delivered up to a total dose of 60-64 Gy with a 2.0 Gy dose fraction per day, 5 days per week. Results: The overall response rates of primary tumor and mediastinum metastatic node were 86.8% (33/38) and 90.6% (29/32) respectively, and 91.7% (22/24) and 78.6% (11/14) for squamous cell carcinoma and adenocarcinoma respectively. The acute side effects of patients were mostly myelosuppression, nausea, vomiting, radiation-induced esophagitis and pneumonitis (RTOG 1/11), however, all of them were cured. Conclusion: Concurrent application of gemcitabine and 3D-CRT can improve the overall response rate for locally advanced NSCLC without aggravating the side effects. 展开更多
关键词 non-small cell lung cancer three-dimensional conformal radiation therapy CHEMOTHERAPY concurrent chemoradiotherapy GEMCITABINE
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Three-dimensional stability of landslides based on local safety factor 被引量:4
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作者 YANG Tao Man-chu Ronald YEUNG +2 位作者 YANG Bing LIU Yong-jiang YANG Yan-xin 《Journal of Mountain Science》 SCIE CSCD 2016年第9期1515-1526,共12页
Unlike the limit equilibrium method(LEM), with which only the global safety factor of the landslide can be calculated, a local safety factor(LSF) method is proposed to evaluate the stability of different sections of a... Unlike the limit equilibrium method(LEM), with which only the global safety factor of the landslide can be calculated, a local safety factor(LSF) method is proposed to evaluate the stability of different sections of a landslide in this paper. Based on three-dimensional(3D) numerical simulation results, the local safety factor is defined as the ratio of the shear strength of the soil at an element on the slip zone to the shear stress parallel to the sliding direction at that element. The global safety factor of the landslide is defined as the weighted average of all local safety factors based on the area of the slip surface. Some example analyses show that the results computed by the LSF method agree well with those calculated by the General Limit Equilibrium(GLE) method in two-dimensional(2D) models and the distribution of the LSF in the 3D slip zone is consistent with that indicated by the observed deformation pattern of an actual landslide in China. 展开更多
关键词 Landslide stability local safety factor Stability analysis method Slip mechanism
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High-precision three-dimensional atom localization via probe absorption at room temperature
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作者 Mengmeng Luo Wenxiao Liu +1 位作者 Dingyu Cai Shaoyan Gao 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第12期258-264,共7页
A scheme is used to explore the behavior of three-dimensional(3D)atom localization in a Y-type hot atomic system.We can obtain the position information of the atom due to the position-dependent atom–field interaction... A scheme is used to explore the behavior of three-dimensional(3D)atom localization in a Y-type hot atomic system.We can obtain the position information of the atom due to the position-dependent atom–field interaction.We study the influences of the system parameters and the temperature on the atom localization.More interestingly,the atom can be localized in a subspace when the temperature is equal to 323 K.Moreover,a method is proposed to tune multiparameter for localizing the atom in a subspace.The result is helpful to achieve atom nanolithography,photonic crystal and measure the center-of-mass wave function of moving atoms. 展开更多
关键词 three-dimensional atom localization probe absorption Doppler effect
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Bi-level hybrid local search approach for three-dimensional loading problem with balancing constraints 被引量:3
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作者 ZHU Xiang LEI Ding-you 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第4期903-918,共16页
This paper presents a bi-level hybrid local search(BHLS)algorithm for the three-dimensional loading problem with balancing constraints(3DLP-B),where several rectangular boxes with even densities but different sizes ar... This paper presents a bi-level hybrid local search(BHLS)algorithm for the three-dimensional loading problem with balancing constraints(3DLP-B),where several rectangular boxes with even densities but different sizes are loaded into a single cubic bin to meet the requirements of the space or capacity utilization and the balance of the center of gravity.The proposed algorithm hybridizes a novel framed-layout procedure in which the concept of the core block and its generation strategy are introduced.Once the block-loading sequence has been determined,we can load one block at a time by the designed construction heuristic.Then,the double-search is introduced;its external search procedure generates a list of compact packing patterns while its internal search procedure is used to search the core-block frames and their best distribution locations.The approach is extensively tested on weakly to strongly heterogeneous benchmark data.The results show that it has better performance in improving space utilization rate and balanced condition of the placement than existed techniques:the overall averages from 79.85%to 86.45%were obtained for the balanced cases and relatively high space-usage rate of 89.44%was achieved for the unbalanced ones. 展开更多
关键词 3D loading balancing constraints framed layout bi-level hybrid local search core block
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Three-dimensional models:from cell culture to Patient-Derived Organoid and its application to future liposarcoma research
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作者 SAYUMI TAHARA SYDNEY RENTSCH +4 位作者 FERNANDA COSTAS CASAL DE FARIA PATRICIA SARCHET ROMA KARNA FEDERICA CALORE RAPHAEL E.POLLOCK 《Oncology Research》 SCIE 2025年第1期1-13,共13页
Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma ... Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma pathobiology.Conventional cell culture-based research(2D cell culture)is still playing a pivotal role,while several shortcomings have been recently under discussion.In vivo,mouse models are usually adopted for pre-clinical analyses with expectations to overcome the issues of 2D cell culture.However,they do not fully recapitulate human dedifferentiated liposarcoma(DDLPS)characteristics.Therefore,three-dimensional(3D)culture systems have been the recent research focus in the cell biology field with the expectation to overcome at the same time the disadvantages of 2D cell culture and in vivo animal models and fill in the gap between them.Given the liposarcoma rarity,we believe that 3D cell culture techniques,including 3D cell cultures/co-cultures,and Patient-Derived tumor Organoids(PDOs),represent a promising approach to facilitate liposarcoma investigation and elucidate its molecular mechanisms and effective therapy development.In this review,we first provide a general overview of 3D cell cultures compared to 2D cell cultures.We then focus on one of the recent 3D cell culture applications,Patient-Derived Organoids(PDOs),summarizing and discussing several PDO methodologies.Finally,we discuss the current and future applications of PDOs to sarcoma,particularly in the field of liposarcoma. 展开更多
关键词 Cell culture LIPOSARCOMA Patient-Derived Organoid(PDO) SPHEROID three-dimensional(3D)cell culture
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Localized space-tim e method of fundamental solutions for three-dimensional transient diffusion problem 被引量:2
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作者 L.Qiu J.Lin +1 位作者 Q.-H.Qin W.Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2020年第5期1051-1057,I0002,共8页
A localized space-time method of fundamental solutions(LSTMFS)is extended for solving three-dimensional transient diffusion problems in this paper.The interval segmentation in temporal direction is developed for the a... A localized space-time method of fundamental solutions(LSTMFS)is extended for solving three-dimensional transient diffusion problems in this paper.The interval segmentation in temporal direction is developed for the accurate simulation of long-time-dependent diffusion problems.In the LSTMFS,the whole space-time domain with nodes arranged i divided into a series of overlapping subdomains with a simple geometry.In each subdomain,the conventional method of fundamental solutions is utilized and the coefficients associated with the considered domain can be explicitly determined.By calculating a combined sparse matrix system,the value at any node inside the space-time domain can be obtained.Numerical experi-ments demonstrate that high accuracy and efficiency can be simultaneously achieved via the LSTMFS,even for the problems defined on a long-time and quite complex computational domain. 展开更多
关键词 localized spacetime method of fundamental solutions Meshless method Long-time evolution Transient diffusion
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Glasses-free three-dimensional laparoscopic systems in oncologic surgery:Innovation or equivalence?
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作者 Gustavo Eder González Alvarez Christian Ramírez Sánchez +3 位作者 Melissa Martínez Nieto Mario A Alarcón-Sánchez Juan JoséVarela-Hernández Sarah M LomelíMartínez 《World Journal of Gastrointestinal Surgery》 2025年第11期6-11,共6页
The development of minimally invasive surgery has transformed the management of gastrointestinal cancer.Notably,three-dimensional visualization systems have increased surgical precision.This editorial discusses a rece... The development of minimally invasive surgery has transformed the management of gastrointestinal cancer.Notably,three-dimensional visualization systems have increased surgical precision.This editorial discusses a recent study by Shen and Zhang,which compared the clinical applications of naked-eye threedimensional laparoscopic systems vs traditional optical systems in radical surgery for gastric and colorectal cancer.Both systems appeared to yield comparable surgical and oncological outcomes in terms of safety parameters,operating times,and quality of lymph node dissection.However,the spectacle-free system’s technical and logistical limitations hindered its effects on the surgical team’s overall competency.This editorial examines the authors’findings within the broader context of the evolution of oncologic laparoscopy,discusses the relevance of the results in light of the current literature,and proposes future research directions focused on multicenter validation,comprehensive ergonomic analysis,and technological advancements aimed at enhancing intraoperative collaboration.As technology continues to evolve,clinical implementation of new methods must be supported by robust scientific evidence and standardized criteria,to ensure tangible improvements in efficiency,safety,and oncologic outcomes. 展开更多
关键词 Autostereoscopic three-dimensional technology Laparoscopic surgery three-dimensional laparoscopy Twodimensional laparoscopy Oncologic surgery
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A Three-Dimensional Range-Free Localization Algorithm Based on Mobile Beacons for Wireless Sensor Networks 被引量:3
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作者 GUERRERO E ALVAREZ J RIVERO L 《Computer Aided Drafting,Design and Manufacturing》 2010年第1期83-92,共10页
In wireless sensor networks (WSNs) the position information of individual nodes is a matter of vital importance because allows the implementation of necessary network functions such as routing, querying and other ap... In wireless sensor networks (WSNs) the position information of individual nodes is a matter of vital importance because allows the implementation of necessary network functions such as routing, querying and other applications. The objective of this paper is to propose an algorithm of three-dimensional distributed range-free localization for WSNs, using a mobile beacon (MB) equipped with a rotary and tilting directional antenna. This algorithm, denominated as the three-dimensional azimuthally defined area localization algorithm (3D- ADAL), is executed in each sensor node and is based only on the analysis of the information received from the MB, therefore is energy efficient and contributes to extend the lifetime of the sensor network. Additionally the proposed algorithm has the advantage of being simple and economical. The simulation results show that the proposed algorithm is a practical, effective and accurate method for a three-dimensional location of sensor nodes in a WSN. 展开更多
关键词 3D localization wireless sensor network mobile beacon directional antenna
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Investigation into the degradation of 2,4,6-trichlorophenol utilizing a three-dimensional electrocatalytic reactor filled with fluorine-doped copper-carbon particle electrodes
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作者 Hongrui Zhang Wenyu Huang +4 位作者 Hainong Song Hanhui Yan Jia Zhang Fang Zhong Huilan Li 《Journal of Environmental Sciences》 2025年第9期701-719,共19页
The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated cata... The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated catalytic activity and minimal energy consumption continues to pose a significant challenge.In this research,Fluorine-doped copper-carbon(F/Cu-GAC)particle electrodes were effectively synthesized through an impregnationcalcination technique,utilizing granular activated carbon as the carrier and fluorinedoped modified copper oxides as the catalytic agents.The particle electrodes were subsequently utilized to promote the degradation of 2,4,6-trichlorophenol(2,4,6-TCP)in a threedimensional electrocatalytic reactor(3DER).The F/Cu-GAC particle electrodes were polarized under the action of electric field,which promoted the heterogeneous Fenton-like reaction in which H2O2 generated by two-electron oxygen reduction reaction(2e-ORR)of O_(2) was catalytically decomposed to·OH.The 3DER equipped with F/Cu-GAC particle electrodes showed 100%removal of 2,4,6-TCP and 79.24%removal of TOC with a specific energy consumption(EC)of approximately 0.019 kWh/g·COD after 2 h of operation.The F/Cu-GAC particle electrodes exhibited an overpotential of 0.38 V and an electrochemically active surface area(ECSA)of 715 cm^(2),as determined through linear sweep voltammetry(LSV)and cyclic voltammetry(CV)assessments.These findings suggest a high level of electrocatalytic performance.Furthermore,the catalytic mechanism of the 3DER equipped with F/Cu-GAC particle electrodes was elucidated through the application of X-ray photoelectron spectroscopy(XPS),electron spin resonance(ESR),and active species capture experiments.This investigation offers a novel approach for the effective degradation of 2,4,6-TCP. 展开更多
关键词 2 4 6-TRICHLOROPHENOL Heterogeneous Fenton-like process three-dimensional electrocatalytic reactor three-dimensional particle electrode system Fluorine-doped copper-carbon particle electrodes
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A Review of Three-Dimensional Research on Urban Recreation Space Based on CiteSpace
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作者 LIU Yongli 《Journal of Landscape Research》 2025年第1期30-34,共5页
In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring t... In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring the scientific development trend and research hotspots in this field.The results show that the number of published documents shows a fluctuating upward trend,and the significant growth rate reflects the role of policy orientation in promoting the concept of compact city.The co-occurrence analysis of keywords reveals the research hotspots of“compact city”,“recreation space”and“urban park”,while the emergence of new keywords such as“vertical city”and“spatial justice”indicates the new trend of recent research.The cluster analysis and timeline map further show the evolution of research themes,with“compact city”being the largest cluster and having rich connections with other themes such as“urban design”and“urban park”. 展开更多
关键词 Compact city Urban recreation space three-dimensional CITESPACE
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Resection of a ganglioneuroma encasing major blood vessels using three-dimensional laparoscopy combined with organ suspension:A case report
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作者 Guo-Zhen Wu Shen-Zhe Fang +1 位作者 Shi-An Yu Min Yu 《World Journal of Gastrointestinal Surgery》 2025年第8期467-475,共9页
BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major... BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major blood vessels remains a substantial clinical challenge.Traditionally,these cases often require open abdominal surgery or combined organ resections,and in some instances,the tumors are considered unresectable.Currently,no reports have described the resection of such tumors via laparoscopy.CASE SUMMARY A 35-year-old woman was admitted to our hospital after the incidental discovery of a retroperitoneal space-occupying lesion.Imaging revealed a mass with the celiac axis and superior mesenteric artery passing through it.A neurogenic tumor was suspected,with ganglioneuroma being the most likely diagnosis.Following comprehensive preoperative preparation,the retroperitoneal tumor was resected using a three-dimensional laparoscopy combined with an organ suspension technique.The surgical approach involved incising the tumor along the vascular axis and conducting meticulous,vascular-preserving tumor excision.The operation lasted approximately 458 minutes,with an estimated blood loss of 50 mL.The patient was discharged on the 8th postoperative day.A transient liver injury occurred after surgery but improved rapidly.After 11 months of postoperative follow-up,no complications or tumor recurrence were observed.CONCLUSION This case illustrates the feasibility of minimally invasive laparoscopic resection for retroperitoneal ganglioneuromas encasing major blood vessels. 展开更多
关键词 Ganglioneuromas Retroperitoneal three-dimensional laparoscopy Organ suspension Case report
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Reconfigurable Three-Dimensional Thermal Dome
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作者 Yuhong Zhou Fubao Yang +5 位作者 Liujun Xu Pengfei Zhuang Dong Wang Xiaoping Ouyang Ying Li Jiping Huang 《Engineering》 2025年第3期236-244,共9页
Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of t... Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of thermal invisibility schemes,they still face two limitations in practical applications.First,objects are typically completely enclosed in traditional cloaks,making them difficult to use and unsuitable for objects with heat sources.Second,although some theoretical proposals have been put forth to change the thermal conductivity of materials to achieve dynamic invisibility,their designs are complex and rigid,making them unsuitable for large-scale use in real threedimensional(3D)spaces.Here,we propose a concept of a thermal dome to achieve 3D invisibility.Our scheme includes an open functional area,greatly enhancing its usability and applicability.It features a reconfigurable structure,constructed with simple isotropic natural materials,making it suitable for dynamic requirements.The performance of our reconfigurable thermal dome has been confirmed through simulations and experiments,consistent with the theory.The introduction of this concept can greatly advance the development of thermal invisibility technology from theory to engineering and provide inspiration for other physical domains,such as direct current electric fields and magnetic fields. 展开更多
关键词 Thermal domes Reconfigurable metamaterials three-dimensional invisibility
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Three-dimensional spectral analysis of gravity waves from airglow observations over Northwest China
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作者 QinZeng Li JiYao Xu +3 位作者 Wei Yuan Xiao Liu YaJun Zhu WeiJun Liu 《Earth and Planetary Physics》 2025年第4期988-994,共7页
The three-dimensional spectral analysis method was applied to airglow data from September 2023 to August 2024 derivedfrom an OH airglow imager located at the Hejing station (42.79°N, 83.73°E) to study the pr... The three-dimensional spectral analysis method was applied to airglow data from September 2023 to August 2024 derivedfrom an OH airglow imager located at the Hejing station (42.79°N, 83.73°E) to study the propagation characteristics of gravity waves(GWs) over Northwest China. We found that obvious seasonal variations occur in the propagation of GWs. In spring, GWs mainlypropagate in the northeast direction. In summer and autumn, GWs mainly propagate in the north direction. However, GWs mainlypropagate in the south direction in winter. The direction of GW propagation in the zonal direction is controlled by the wind-filteringeffect, whereas the north–south meridional direction is mainly determined by the location of the wave source. We found that the averageenergy spectrum exhibits a 10%–20% higher intensity in summer and winter compared with spring and autumn. For the first time, wereport the seasonal variation characteristics of GWs over the inland areas of Northwest China, which is of great significance forunderstanding the regional distribution characteristics of GWs. 展开更多
关键词 AIRGLOW gravity wave three-dimensional spectral analysis seasonal variation
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Three-dimensional internal multiple elimination in complex structures using Marchenko autofocusing theory
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作者 Pei-Nan Bao Ying Shi +2 位作者 Xin-Min Shang Hong-Xian Liang Wei-Hong Wang 《Petroleum Science》 2025年第1期222-233,共12页
Internal multiples are commonly present in seismic data due to variations in velocity or density of subsurface media.They can reduce the signal-to-noise ratio of seismic data and degrade the quality of the image.With ... Internal multiples are commonly present in seismic data due to variations in velocity or density of subsurface media.They can reduce the signal-to-noise ratio of seismic data and degrade the quality of the image.With the development of seismic exploration into deep and ultradeep events,especially those from complex targets in the western region of China,the internal multiple eliminations become increasingly challenging.Currently,three-dimensional(3D)seismic data are primarily used for oil and gas target recognition and drilling.Effectively eliminating internal multiples in 3D seismic data of complex structures and mitigating their adverse effects is crucial for enhancing the success rate of drilling.In this study,we propose an internal multiple prediction algorithm for 3D seismic data in complex structures using the Marchenko autofocusing theory.This method can predict the accurate internal multiples of time difference without an accurate velocity model and the implementation process mainly consists of several steps.Firstly,simulating direct waves with a 3D macroscopic velocity model.Secondly,using direct waves and 3D full seismic acquisition records to obtain the upgoing and down-going Green's functions between the virtual source point and surface.Thirdly,constructing internal multiples of the relevant layers by upgoing and downgoing Green's functions.Finally,utilizing the adaptive matching subtraction method to remove predicted internal multiples from the original data to obtain seismic records without multiples.Compared with the two-dimensional(2D)Marchenko algo-rithm,the performance of the 3D Marchenko algorithm for internal multiple prediction has been significantly enhanced,resulting in higher computational accuracy.Numerical simulation test results indicate that our proposed method can effectively eliminate internal multiples in 3D seismic data,thereby exhibiting important theoretical and industrial application value. 展开更多
关键词 Marchenko Internal multiple elimination Autofocusing three-dimensional seismic data
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Three-dimensional reconstruction under computed tomography and myopectineal orifice measurement under laparoscopy for quality control of inguinal hernia treatment
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作者 Lei Zhang Jing Chen +7 位作者 Yu-Ying Zhang Lei Liu Han-Dan Wang Ya-Fei Zhang Jun Sheng Qiu-Shi Hu Ming-Liang Liu Yi-Lin Yuan 《World Journal of Gastrointestinal Endoscopy》 2025年第3期50-59,共10页
BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are ne... BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are necessary.However,due to differences in race and sex,people’s body shapes vary.According to European guidelines,the patch should measure 10 cm×15 cm.If any part of the MPO is dissected,injury to the nerves,vascular network,or organs may occur during surgery,thereby leading to inguinal discomfort,pain,and seroma formation after surgery.Therefore,accurate localization and measurement of the boundary of the MPO are crucial for selecting the optimal patch for inguinal hernia repair.AIM To compare the size of the MPO measured on three-dimensional multislice spiral computed tomography(CT)with that measured via laparoscopy and explore the relevant factors influencing the size of the MPO.METHODS Clinical data from 74 patients who underwent laparoscopic tension-free inguinal hernia repair at the General Surgery Department of the First Affiliated Hospital of Anhui University of Science and Technology between September 2022 and July 2024 were collected and analyzed retrospectively.Transabdominal preperitoneal was performed.Sixty-four males and 10 females,with an average age of 58.30±12.32 years,were included.The clinical data of the patients were collected.The boundary of the MPO was measured on three-dimensional CT images before surgery and then again during transabdominal preperitoneal.All the preoperative and intraoperative data were analyzed via paired t-tests.A t-test was used for comparisons of age,body mass index,and sex between the groups.In the comparative analysis,a P value less than 0.05 indicated a significant difference.RESULTS The boundaries of the MPO on 3-dimensional CT images measured 7.05±0.47 cm and 6.27±0.61 cm,and the area of the MPO was 19.54±3.33 cm^(2).The boundaries of the MPO during surgery were 7.18±0.51 cm and 6.17±0.40 cm.The errors were not statistically significant.However,the intraoperative BD(the width of the MPO,P=0.024,P<0.05)and preoperative AC(the length of the MPO,P=0.045,P<0.05)significantly differed according to sex.The AC and BD measurements before and during surgery were not significantly different according to age,body mass index,hernia side or hernia type(P>0.05).CONCLUSION The application of this technology can aid in determining the most appropriate dissection range and patch size. 展开更多
关键词 HERNIA INGUINAL Myopectineal orifice three-dimensional reconstruction Computed tomography Inguinal hernia
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