With the widespread deployment of assembly robots in smart manufacturing,efficiently offloading tasks and allocating resources in highly dynamic industrial environments has become a critical challenge for Mobile Edge ...With the widespread deployment of assembly robots in smart manufacturing,efficiently offloading tasks and allocating resources in highly dynamic industrial environments has become a critical challenge for Mobile Edge Computing(MEC).To address this challenge,this paper constructs a cloud-edge-end collaborative MEC system that enables assembly robots to offload complex workflow tasks via multiple paths(horizontal,vertical,and hybrid collaboration).Tomitigate uncertainties arising frommobility,the location predictionmodule is employed.This enables proactive channel-quality estimation,providing forward-looking insights for offloading decisions.Furthermore,we propose a fairness-aware joint optimization framework.Utilizing an improved Multi-Agent Deep Reinforcement Learning(MADRL)algorithm whose reward function incorporates total system cost,positional reliability,and timeout penalties,the framework aims to balance resource distribution among assembly robots while maximizing system utility.Simulation results demonstrate that the proposed framework outperforms traditional offloading strategies.By integrating predictive mobility management with fairness-aware optimization,the framework offers a robust solution for dynamic industrial MEC environments.展开更多
The diversion effect caused by the linked structure in a metro tunnel with cross-passage complicates the impact of longitudinal fire source location on the smoke backflow layering behavior that has not been clarified,...The diversion effect caused by the linked structure in a metro tunnel with cross-passage complicates the impact of longitudinal fire source location on the smoke backflow layering behavior that has not been clarified,despite the fact that the scenario exists in practice.A series of laboratory-scale experiments were conducted in this study to investigate the smoke back-layering length in a model tunnel with cross-passage.The heat release rate,the velocity of longitudinal air flow,and the location of the fire source were all varied.It was found that the behavior of smoke backflow for the fire source located at the upstream of bifurcation point resembles a single-hole tunnel fire.As the fire source’s position shifts downstream from the bifurcation point,the length of smoke back-layering progressively increases.A competitive interaction exists between airflow diversion and smoke diversion during smoke backflow,significantly affecting the smoke back-layering length in the main tunnel.The dimensionless smoke back-layering length model was formulated in a tunnel featuring a cross-passage,taking into account the positions of longitudinal fire sources.The dimensionless smoke back-layering length exhibits a positive correlation with the 17/18 power of total heat release rate Q and a negative correlation with the 5/2 power of longitudinal ventilation velocity V.展开更多
With the popularization of smart devices,Location-Based Services(LBS)greatly facilitates users’life,but at the same time brings the risk of users’location privacy leakage.Existing location privacy protection methods...With the popularization of smart devices,Location-Based Services(LBS)greatly facilitates users’life,but at the same time brings the risk of users’location privacy leakage.Existing location privacy protection methods are deficient,failing to reasonably allocate the privacy budget for non-outlier location points and ignoring the critical location information that may be contained in the outlier points,leading to decreased data availability and privacy exposure problems.To address these problems,this paper proposes a Mix Location Privacy Preservation Method Based on Differential Privacy with Clustering(MLDP).The method first utilizes the DBSCAN clustering algorithm to classify location points into non-outliers and outliers.For non-outliers,the scoring function is designed by combining geographic information and semantic information,and the privacy budget is allocated according to the heat intensity of the hotspot area;for outliers,the scoring function is constructed to allocate the privacy budget based on their correlation with the hotspot area.By comprehensively considering the geographic information,semantic information,and correlation with hotspot areas of the location points,a reasonable privacy budget is assigned to each location point,andfinallynoise is added throughthe Laplacemechanismto realizeprivacyprotection.Experimental results on tworeal trajectory datasets,Geolife and T-Drive,show that the MLDP approach significantly improves data availability while effectively protecting location privacy.Compared with the comparison methods,the maximum available data ratio of MLDP is 1.Moreover,compared with the RandomNoise method,its execution time is 0.056–0.061 s longer,and the logRE is 0.12951–0.62194 lower;compared with KemeansDP,QTK-DP,DPK-F,IDP-SC,and DPK-Means-up methods,it saves 0.114–0.296 s in execution time,and the logRE is 0.01112–0.38283 lower.展开更多
Traveling wave(TW)fault location technology has been widely used in transmission systems due to its high accuracy and simplicity.Recently,there has been growing interest in applying this technology to medium voltage(M...Traveling wave(TW)fault location technology has been widely used in transmission systems due to its high accuracy and simplicity.Recently,there has been growing interest in applying this technology to medium voltage(MV)distribution lines.However,current practices in its deployment,signal measurement,and threshold setting are usually from the application experiences in transmission lines,despite significant differences in fault-induced wave characteristics between transmission and distribution systems.To address these issues,this paper investigates the feasibility and applicability of TW fault technology in MV overhead distribution lines through characteristic analysis of fault-induced TWs.The propagation characteristics of aerial mode and zero mode TWs on overhead distribution lines are studied.Furthermore,it evaluates the influence of critical distri-bution network components including distribution transformers,multi-branch configurations,and busbar structures on wave propagation characteristics.Deployment strategies for traveling wave fault location(TWFL)devices is proposed to address the unique challenges of distribution networks,while the fault location method is also improved.Field test results demonstrate the effectiveness of the proposed methodology,showing improved fault detection accuracy and system reliability in distri-bution network applications.This research provides practical implementation suggestions for TWFL technology in distribution networks.展开更多
International patients are flocking to Hainan for healing through the ancient technique of traditional Chinese medicine.SAREN,a traditional Chinese medicine(TCM)doctor,keeps vipbooks filled with warm messages in var...International patients are flocking to Hainan for healing through the ancient technique of traditional Chinese medicine.SAREN,a traditional Chinese medicine(TCM)doctor,keeps vipbooks filled with warm messages in various languages in her consulting room at Sanya International Friendship Sanatorium of TCM.These expressions of gratitude not only document a long medical career,but also vividly testify to how a Chinese doctor has used acupuncture to cure patients from around the world.展开更多
Objective: To investigate the clinical efficacy and safety of auricular acupressure therapy in elderly patients with type 2 diabetic neurogenic bladder, and to provide a feasible external treatment intervention plan b...Objective: To investigate the clinical efficacy and safety of auricular acupressure therapy in elderly patients with type 2 diabetic neurogenic bladder, and to provide a feasible external treatment intervention plan based on traditional Chinese medicine (TCM) for such patients. Methods: A randomized controlled study was conducted, selecting elderly patients with type 2 diabetic neurogenic bladder who met the inclusion criteria and randomly dividing them into a control group and an observation group. The control group received conventional comprehensive diabetes management and bladder function training, while the observation group additionally received auricular acupressure therapy, involving continuous stimulation of relevant auricular points such as Shenmen, Subcortex, Sympathetic, Kidney, Bladder, and Urethra, for a treatment duration of two courses. Changes in maximum urinary flow rate, bladder residual urine volume, TCM syndrome scores, and quality of life index (QOL) were compared between the two groups before and after treatment, and adverse reactions during treatment were recorded and analyzed. Results: After treatment, the observation group demonstrated superior improvement in clinical symptoms such as dysuria and urinary retention compared to the control group, with a significant increase in maximum urinary flow rate, a notable decrease in bladder residual urine volume and TCM syndrome scores, and a concurrent improvement in quality-of-life scores. The differences between the groups were statistically significant (p < 0.05). No serious adverse events occurred during treatment, and minor local discomfort resolved spontaneously after management, indicating overall good safety. Conclusion: As a simple and persistent TCM external treatment method, auricular acupressure therapy can further improve urinary function and quality of life in elderly patients with type 2 diabetic neurogenic bladder when combined with conventional treatment, with high safety and certain clinical promotion value.展开更多
This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 3:Mouse.This standard was released by the China Associ...This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 3:Mouse.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU.展开更多
Objective The analgesic effect of acupuncture has been widely accepted.Nevertheless,the mechanism behind its analgesic effect remains elusive,thus impeding the progress of research geared toward enhancing the analgesi...Objective The analgesic effect of acupuncture has been widely accepted.Nevertheless,the mechanism behind its analgesic effect remains elusive,thus impeding the progress of research geared toward enhancing the analgesic effect of acupuncture.This paper investigated the role of acupuncture needle surface textures on acupuncture’s analgesic effect by creating four experimental acupuncture needles with different patterns of surface augmentation.Methods Four types of acupuncture needles with different surface textures(the lined needle,circle needle,sandpaper needle,and threaded needle)were designed.Additionally,the force/torque measurement system used a robot arm and mechanical sensor to measure the force on the needle during insertion and manipulation.To perform acupuncture analgesia experiments,four experimental acupuncture needles and a normal needle were inserted into the Zusanli(ST36)acupoint of rats with inflammatory pain.By comparing the force and torque and the analgesic efficacy of the different acupuncture needles,these experiments tested the role of acupuncture needle body texture on acupuncture analgesia.Results The analgesic effects of different acupuncture needle body textures varied.Specifically,the force required to penetrate the skin with the lined needle was not greater than that for the normal needle;however,the needle with inscribed circles and the sandpaper-roughened needle both required greater force for insertion.Additionally,the torque of the lined needle reached 2×10^(-4)N·m under twisting manipulation,which was four times greater the torque of a normal needle(5×10^(-5)N·m).Furthermore,the lined needle improved pain threshold and mast cell degranulation rate compared to the normal needle.Conclusion Optimizing the texture of acupuncture needles can enhance acupuncture analgesia.The texture of our experimental acupuncture needles had a significant impact on the force needed to penetrate the skin and the torque needed to manipulate the needle;it was also linked to variable analgesic effects.This study provides a theoretical basis for enhancing the analgesic efficacy of acupuncture through the modification of needles and promoting the development of acupuncture therapy.展开更多
This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 2:Rat.This standard was released by the China Associat...This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 2:Rat.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-Zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU.展开更多
Despite advances in surgery,chemotherapy,and radiotherapy,the treatment of colorectal cancer(CRC)requires more personalized approaches based on tumor biology and molecular profiling.While some relevant mutations have ...Despite advances in surgery,chemotherapy,and radiotherapy,the treatment of colorectal cancer(CRC)requires more personalized approaches based on tumor biology and molecular profiling.While some relevant mutations have been associated with differential response to immunotherapy,such as RAS and BRAF mutations limiting response to anti-epithelial growth factor receptor drugs or microsatellite instability predisposing susceptibility to immune checkpoint inhibitors,the role of inflammation in dictating tumor progression and treatment response is still under investigation.Several inflammatory biomarkers have been identified to guide patient prognosis.These include the neutrophil-lymphocyte ratio,Glasgow prognostic score(GPS)and its modified version,lymphocyte-Creactive protein ratio,and platelet-lymphocyte ratio.However,these markers are not yet included in the standard clinical management of patients with CRC,and further research is needed to evaluate their efficacy in different patient populations.A recent study by Wang et al,published in the World Journal of Gastroenterology,sheds light on the prognostic significance of pan-immune-inflammation value(PIV)in CRC,particularly concerning primary tumor location.Specifically,the authors found that a high PIV was strongly correlated with worse disease-free survival in patients with left-sided colon cancer,whereas no such association was observed in patients with right-sided colon cancer.Integrating tumor location into the prognostic assessment of CRC may improve our ability to more accurately identify high-risk patients and develop personalized treatment plans that are more likely to improve patient outcomes.展开更多
BACKGROUND Laparoscopic surgery,with the advantage of less trauma,has been predominantly performed to treat pediatric inguinal hernia.However,the traditional three-port laparoscopic surgery remains extremely traumatic...BACKGROUND Laparoscopic surgery,with the advantage of less trauma,has been predominantly performed to treat pediatric inguinal hernia.However,the traditional three-port laparoscopic surgery remains extremely traumatic for children,whereas singleport laparoscopic surgery causes less damage to children than traditional laparoscopy.However,single-port laparoscopic surgery is more challenging;thus,studies on the effect of its application in pediatric inguinal hernia remain relatively limited.AIM To analyze the association of single-incision laparoscopic herniorrhaphy needle treatment with surgical outcomes,postoperative complications,and serum inflammation in pediatric inguinal hernia.METHODS This retrospective study included 113 pediatric patients with inguinal hernia who underwent surgery at the Children’s Hospital,Capital Institute of Pediatrics,from April 2022 to May 2023.Participants were categorized into the observation group(single-incision laparoscopic herniorrhaphy needle,n=60)and the control group(two-port laparoscopic surgery,n=53).Comparative analyses involved surgical duration,intraoperative blood loss,and length of hospital stay.C-reactive protein(CRP)and white blood cell count(WBC)levels were measured preoperatively and 24 hours postoperatively.Postoperative pain was evaluated with the face,legs,activity,cry,and Consolability scale.Further,the incidence of complications,recurrence,and reoperation rates was assessed.Logistic regression was employed to determine independent risk factors related to poor prognosis.RESULTS The observation group demonstrated significantly reduced intraoperative blood loss and shorter hospitalization compared to the control group(P<0.05).Both groups demonstrated increased CRP and WBC levels postoperatively,but the observation group exhibited significantly lower levels(P<0.05).Further,pain scores at 24 hours postoperatively were significantly lower in the observation group(P<0.05).Additionally,the observation group experienced fewer adverse events,recurrence rates,and reoperations compared to the control group(P<0.05).Logistic regression analysis determined increased postoperative stress markers and surgical technique as independent predictors of recurrence(P<0.05).CONCLUSION Single-incision laparoscopic herniorrhaphy needle treatment for pediatric inguinal hernia exhibits significant efficacy,effectively reduces postoperative complications,ensures a more concealed surgical incision,and promotes faster postoperative recovery than conventional two-port laparoscopy.This approach merits wider application.展开更多
OBJECTIVE:To assess the efficacy and safety of the Qingyanyin formulated granules(轻燕饮配方颗粒,QYY),press needles(PN),and their combined application in addressing abdominal obesity(AO).This trial aims to offer a mor...OBJECTIVE:To assess the efficacy and safety of the Qingyanyin formulated granules(轻燕饮配方颗粒,QYY),press needles(PN),and their combined application in addressing abdominal obesity(AO).This trial aims to offer a more scientifically grounded therapeutic regimen for clinical interventions.METHODS:From March 2021 to July 2021,a multicenter,triple-blind,randomized 2×2 factorial design clinical trial was conducted across 7 centers in 4 major cities within China's mainland.The trial participants were patients diagnosed with AO.The trial followed a 1∶1∶1∶1 random allocation ratio,assigning participants to one of four groups:QYY placebo plus simulated press needles(SPN)(placebo+SPN),QYY plus SPN(QYY+SPN),QYY placebo plus PN(placebo+PN),and QYY plus PN(QYY+PN).The trial participants received treatment for 12 weeks.Observe the changes in waist circumference,body weight,body mass index(BMI),Beck Depression Inventory(BDI),Beck Anxiety Inventory(BAI)scores,and Pittsburgh Sleep Quality Index(PSQI)before and after treatment.RESULTS:The QYY+PN group exhibited significant improvements in waist circumference compared to placebo+PN[Difference=-1.59,95%CI(-3.03,-0.16)]and placebo+SPN groups[Difference=-2.01,95%CI(-3.46,-0.57)].QYY+PN demonstrated a significant advantage over placebo+SPN[Difference=-2.01,95%CI(-3.46,-0.57)],and no statistically significant interaction was observed between the two interventions(P>0.05).In terms of weight and BMI improvements,the QYY+PN,QYY+SPN,and the PN+placebo groups all experienced trending greater reductions in weight compared to the placebo group.In terms of the total scores of PSQI,BAI,and BDI,all four groups exhibited improvements compared to the baseline.Specifically,concerning the change in total PSQI scores,the QYY+PN group exhibited a greater reduction;Regarding the change in total BAI scores,the PN+placebo group demonstrated a greater decrease;As for the change in total BDI scores,the QYY+SPN group displayed a greater reduction.CONCLUSION:This study confirmed that QYY+PN can effectively reduce the waist circumference of patients with AO.Furthermore,the combined approach offers greater benefits than either treatment alone,all without any reported serious adverse events.展开更多
Unmanned aerial vehicle(UAV)swarm network consisting of a collection of micro UAVs can be used for many applications.It is well established that packet routing is a fundamental problem to achieve UAV collaboration.How...Unmanned aerial vehicle(UAV)swarm network consisting of a collection of micro UAVs can be used for many applications.It is well established that packet routing is a fundamental problem to achieve UAV collaboration.However,the highly dynamic nature of UAVs,frequently changing network topologies and security issues,poses significant challenges to packet forwarding in UAV networks.The existing topology-based routing protocols are not well suited in UAV network due to their high controlling overhead or excessive end-to-end delay.Geographic routing is regarded as a promising solution,as it only requires local information.In order to enhance the accuracy and security of geographic routing in highly dynamic UAV network,in this paper,we propose a new predictive geographic(PGeo)routing strategy with location verification.First,a detection mechanism is adopted to recognize malicious UAVs falsifying their location.Then,an accurate average service time of a packet in the medium access control(MAC)layer is derived to assist location prediction.The proposed delay model can provide a theoretical basis for future work,and our simulation results reveal that PGeo outstrips the existing geographic routing protocols in terms of packet delivery ratio in the presence of location spoofing behavior.展开更多
BACKGROUND This is a randomized study to compare the diagnostic accuracy of endoscopic ultrasound(EUS)-guided sampling of pancreatic solid lesions obtained with the 22-gauge Franseen(EUS-fine needle biopsy)vs the 22-g...BACKGROUND This is a randomized study to compare the diagnostic accuracy of endoscopic ultrasound(EUS)-guided sampling of pancreatic solid lesions obtained with the 22-gauge Franseen(EUS-fine needle biopsy)vs the 22-gauge standard needle(EUS-fine needle aspiration)without rapid onsite evaluation(ROSE),since,in most endoscopy units around the world ROSE is not routinely available.AIM To investigate the accuracy of EUS-guided sampling of pancreatic solid lesions obtained between two different needles without ROSE.METHODS Patients with a solid pancreatic were included.Patients were biopsied in a randomized order.The primary endpoint was the diagnostic sensitivity for pancreatic malignancy(PM).Secondary outcomes were adequacy of the sample,the mean tissue area,the mean tumor area,and the adverse event rate.RESULTS The final diagnosis was pancreatic adenocarcinoma in 38(76%),neuroendocrine tumor in 4(8%),chronic pancreatitis in 3(6%)patients.The sensitivity for PM with Franseen needle was 0.91[95%confidence interval(CI):0.80-0.98],vs 0.8(95%CI:0.67-0.91)(P=0.025)with standard needle.The specificity for PM did not differentiate.The accuracy of the standard needle for PM was 0.80(95%CI:0.66-0.90),and the Franseen group was 0.90(95%CI:0.78-0.97)(P=0.074).The technical success rates for the standard and Franseen needle groups were 94%(95%CI:0.83-0.99)and 100%(95%CI:0.92-1.00),respectively.The mean total tissue area in mm2(SD)was greater in the Franseen group,2.07(0.22)vs 1.16(0.17)(P<0.01).The mean tumor area in mm2(SD)was not different in Franseen group vs standard group,0.42(0.09)vs 0.47(0.09)(P=0.80).There were no adverse events.CONCLUSION The sensitivity for PM and mean total tissue area,was greater in the as compared with standard needle.The mean tumor area did not differ between the groups.展开更多
A novel method is developed by utilizing the fractional frequency based multirange rulers to precisely position the passive inter-modulation(PIM)sources within radio frequency(RF)cables.The proposed method employs a s...A novel method is developed by utilizing the fractional frequency based multirange rulers to precisely position the passive inter-modulation(PIM)sources within radio frequency(RF)cables.The proposed method employs a set of fractional frequencies to create multiple measuring rulers with different metric ranges to determine the values of the tens,ones,tenths,and hundredths digits of the distance.Among these rulers,the one with the lowest frequency determines the maximum metric range,while the one with the highest frequency decides the highest achievable accuracy of the position system.For all rulers,the metric accuracy is uniquely determined by the phase accuracy of the detected PIM signals.With the all-phase Fourier transform method,the phases of the PIM signals at all fractional frequencies maintain almost the same accuracy,approximately 1°(about 1/360 wavelength in the positioning accuracy)at the signal-to-noise ratio(SNR)of 10 d B.Numerical simulations verify the effectiveness of the proposed method,improving the positioning accuracy of the cable PIM up to a millimeter level with the highest fractional frequency operating at 200 MHz.展开更多
Semiconductor electronic devices are prone to charge accumulation during production and transportation,which usually causes device breakdown.Ionizers are widely used for electrostatic elimination,and utilizing semicon...Semiconductor electronic devices are prone to charge accumulation during production and transportation,which usually causes device breakdown.Ionizers are widely used for electrostatic elimination,and utilizing semiconductor silicon for the discharge needle material in ionizers can effectively prevent metal contamination.To investigate the discharge characteristics of silicon needles and their mode modulation mechanism,this study has established an experimental platform for silicon needle-plate discharge under positive polarity voltage.Discharge pulse parameters and optical signals were measured at varying electrode spacings.The experimental results reveal that silicon needle discharge progresses through four regimes:the spontaneous streamer,the periodic streamer,the cluster streamer,and the glow discharge.Among these,the pulse amplitude is most uniform and stable in the periodic streamer regime.In addition,shorter-gap discharge exhibits higher pulse amplitude and repetition frequency but is easier to transition into the filament regime.The formation process of a single pulse is closely related to the field strength in the ionization region near the needle tip.Hence,parameters such as the pulse rising edge time and falling edge time show minimal variation with voltage.The amount of charge generated per unit time is primarily influenced by the repetition frequency.Consequently,the electrostatic ionizer produces the highest,most stable,and most uniform charges if it operates in the periodic streamer regime.展开更多
Accurate and rapid determination of source locations is of great significance for surface microseismic monitoring.Traditional methods,such as diffraction stacking,are time-consuming and challenging for real-time monit...Accurate and rapid determination of source locations is of great significance for surface microseismic monitoring.Traditional methods,such as diffraction stacking,are time-consuming and challenging for real-time monitoring.In this study,we propose an approach to locate microseismic events using a deep learning algorithm with surface data.A fully convolutional network is designed to predict source locations.The input data is the waveform of a microseismic event,and the output consists of three 1D Gaussian distributions representing the probability distribution of the source location in the x,y,and z dimensions.The theoretical dataset is generated to train the model,and several data augmentation methods are applied to reduce discrepancies between the theoretical and field data.After applying the trained model to field data,the results demonstrate that our method is fast and achieves comparable location accuracy to the traditional diffraction stacking location method,making it promising for real-time microseismic monitoring.展开更多
Data centers operate as physical digital infrastructure for generating,storing,computing,transmitting,and utilizing massive data and information,constituting the backbone of the flourishing digital economy across the ...Data centers operate as physical digital infrastructure for generating,storing,computing,transmitting,and utilizing massive data and information,constituting the backbone of the flourishing digital economy across the world.Given the lack of a consistent analysis for studying the locational factors of data centers and empirical deficiencies in longitudinal investigations on spatial dynamics of heterogeneous data centers,this paper develops a comprehensive analytical framework to examine the dynamic geographies and locational factors of techno-environmentally heterogeneous data centers across Chinese cities in the period of 2006–2021.First,we develop a“supply-demand-environment trinity”analytical framework as well as an accompanying evaluation indicator system with Chinese characteristics.Second,the dynamic geographies of data centers in Chinese cities over the last decades are characterized as spatial polarization in economically leading urban agglomerations alongside persistent interregional gaps across eastern,central,and western regions.Data centers present dual spatial expansion trajectories featuring outward radiation from eastern core urban agglomerations to adjacent peripheries and leapfrog diffusion to strategic central and western digital infrastructural hubs.Third,it is empirically verified that data center construction in Chinese cities over the last decades has been jointly influenced by supply-,demand-,and environment-side locational factors,echoing the efficacy of the trinity analytical framework.Overall,our findings demonstrate the temporal variance,contextual contingency,and attribute-based differentiation of locational factors underlying techno-environmentally heterogeneous data centers in Chinese cities.展开更多
基金supported by the National Key R&D Program of China under Grant Nos.2024YFD2400200 and 2024YFD2400204supported in part by the Science and Technology Development Program for the Two Zones under Grant No.2023LQ02004.
文摘With the widespread deployment of assembly robots in smart manufacturing,efficiently offloading tasks and allocating resources in highly dynamic industrial environments has become a critical challenge for Mobile Edge Computing(MEC).To address this challenge,this paper constructs a cloud-edge-end collaborative MEC system that enables assembly robots to offload complex workflow tasks via multiple paths(horizontal,vertical,and hybrid collaboration).Tomitigate uncertainties arising frommobility,the location predictionmodule is employed.This enables proactive channel-quality estimation,providing forward-looking insights for offloading decisions.Furthermore,we propose a fairness-aware joint optimization framework.Utilizing an improved Multi-Agent Deep Reinforcement Learning(MADRL)algorithm whose reward function incorporates total system cost,positional reliability,and timeout penalties,the framework aims to balance resource distribution among assembly robots while maximizing system utility.Simulation results demonstrate that the proposed framework outperforms traditional offloading strategies.By integrating predictive mobility management with fairness-aware optimization,the framework offers a robust solution for dynamic industrial MEC environments.
基金funded by the National Natural Science Foundation of China(NSFC)under Grant No.52278415the National Key Research and Development Program of China under Grant No.2022YFC3801104+2 种基金Hebei Provincial Department of Education Project under Grant No.QN2025304the Innovation Fund Project of Hebei University of Engineering under Grant No.SJ2401002066the Sichuan Science and Technology Program under Grant No.2023YFS0407。
文摘The diversion effect caused by the linked structure in a metro tunnel with cross-passage complicates the impact of longitudinal fire source location on the smoke backflow layering behavior that has not been clarified,despite the fact that the scenario exists in practice.A series of laboratory-scale experiments were conducted in this study to investigate the smoke back-layering length in a model tunnel with cross-passage.The heat release rate,the velocity of longitudinal air flow,and the location of the fire source were all varied.It was found that the behavior of smoke backflow for the fire source located at the upstream of bifurcation point resembles a single-hole tunnel fire.As the fire source’s position shifts downstream from the bifurcation point,the length of smoke back-layering progressively increases.A competitive interaction exists between airflow diversion and smoke diversion during smoke backflow,significantly affecting the smoke back-layering length in the main tunnel.The dimensionless smoke back-layering length model was formulated in a tunnel featuring a cross-passage,taking into account the positions of longitudinal fire sources.The dimensionless smoke back-layering length exhibits a positive correlation with the 17/18 power of total heat release rate Q and a negative correlation with the 5/2 power of longitudinal ventilation velocity V.
基金supported in part by the National Natural Science Foundation of China(Grant No.61971291)the Basic Scientific Research Project of the Liaoning Provincial Department of Education(LJ212410144013)+2 种基金the Leading Talent of the‘Xing Liao Ying Cai Plan’(XLYC2202013)the Shenyang Natural Science Foundation(22-315-6-10)the Guangxuan Scholar of Shenyang Ligong University(SYLUGXXZ202205).
文摘With the popularization of smart devices,Location-Based Services(LBS)greatly facilitates users’life,but at the same time brings the risk of users’location privacy leakage.Existing location privacy protection methods are deficient,failing to reasonably allocate the privacy budget for non-outlier location points and ignoring the critical location information that may be contained in the outlier points,leading to decreased data availability and privacy exposure problems.To address these problems,this paper proposes a Mix Location Privacy Preservation Method Based on Differential Privacy with Clustering(MLDP).The method first utilizes the DBSCAN clustering algorithm to classify location points into non-outliers and outliers.For non-outliers,the scoring function is designed by combining geographic information and semantic information,and the privacy budget is allocated according to the heat intensity of the hotspot area;for outliers,the scoring function is constructed to allocate the privacy budget based on their correlation with the hotspot area.By comprehensively considering the geographic information,semantic information,and correlation with hotspot areas of the location points,a reasonable privacy budget is assigned to each location point,andfinallynoise is added throughthe Laplacemechanismto realizeprivacyprotection.Experimental results on tworeal trajectory datasets,Geolife and T-Drive,show that the MLDP approach significantly improves data availability while effectively protecting location privacy.Compared with the comparison methods,the maximum available data ratio of MLDP is 1.Moreover,compared with the RandomNoise method,its execution time is 0.056–0.061 s longer,and the logRE is 0.12951–0.62194 lower;compared with KemeansDP,QTK-DP,DPK-F,IDP-SC,and DPK-Means-up methods,it saves 0.114–0.296 s in execution time,and the logRE is 0.01112–0.38283 lower.
基金supported by the National Natural Sci-ence Foundation of China(No.52107109).
文摘Traveling wave(TW)fault location technology has been widely used in transmission systems due to its high accuracy and simplicity.Recently,there has been growing interest in applying this technology to medium voltage(MV)distribution lines.However,current practices in its deployment,signal measurement,and threshold setting are usually from the application experiences in transmission lines,despite significant differences in fault-induced wave characteristics between transmission and distribution systems.To address these issues,this paper investigates the feasibility and applicability of TW fault technology in MV overhead distribution lines through characteristic analysis of fault-induced TWs.The propagation characteristics of aerial mode and zero mode TWs on overhead distribution lines are studied.Furthermore,it evaluates the influence of critical distri-bution network components including distribution transformers,multi-branch configurations,and busbar structures on wave propagation characteristics.Deployment strategies for traveling wave fault location(TWFL)devices is proposed to address the unique challenges of distribution networks,while the fault location method is also improved.Field test results demonstrate the effectiveness of the proposed methodology,showing improved fault detection accuracy and system reliability in distri-bution network applications.This research provides practical implementation suggestions for TWFL technology in distribution networks.
文摘International patients are flocking to Hainan for healing through the ancient technique of traditional Chinese medicine.SAREN,a traditional Chinese medicine(TCM)doctor,keeps vipbooks filled with warm messages in various languages in her consulting room at Sanya International Friendship Sanatorium of TCM.These expressions of gratitude not only document a long medical career,but also vividly testify to how a Chinese doctor has used acupuncture to cure patients from around the world.
基金Clinical Study on the Treatment of Neurogenic Bladder in Elderly Patients with Type 2 Diabetes Mellitus by Auricular Point Pressing Needle TherapyZhejiang Provincial Traditional Chinese Medicine Science and Technology Project,Zhejiang Provincial People’s Hospital(Project No.:2024ZL252)。
文摘Objective: To investigate the clinical efficacy and safety of auricular acupressure therapy in elderly patients with type 2 diabetic neurogenic bladder, and to provide a feasible external treatment intervention plan based on traditional Chinese medicine (TCM) for such patients. Methods: A randomized controlled study was conducted, selecting elderly patients with type 2 diabetic neurogenic bladder who met the inclusion criteria and randomly dividing them into a control group and an observation group. The control group received conventional comprehensive diabetes management and bladder function training, while the observation group additionally received auricular acupressure therapy, involving continuous stimulation of relevant auricular points such as Shenmen, Subcortex, Sympathetic, Kidney, Bladder, and Urethra, for a treatment duration of two courses. Changes in maximum urinary flow rate, bladder residual urine volume, TCM syndrome scores, and quality of life index (QOL) were compared between the two groups before and after treatment, and adverse reactions during treatment were recorded and analyzed. Results: After treatment, the observation group demonstrated superior improvement in clinical symptoms such as dysuria and urinary retention compared to the control group, with a significant increase in maximum urinary flow rate, a notable decrease in bladder residual urine volume and TCM syndrome scores, and a concurrent improvement in quality-of-life scores. The differences between the groups were statistically significant (p < 0.05). No serious adverse events occurred during treatment, and minor local discomfort resolved spontaneously after management, indicating overall good safety. Conclusion: As a simple and persistent TCM external treatment method, auricular acupressure therapy can further improve urinary function and quality of life in elderly patients with type 2 diabetic neurogenic bladder when combined with conventional treatment, with high safety and certain clinical promotion value.
文摘This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 3:Mouse.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU.
基金funded by National Natural Science Foundation of China(No.12172092,82174488,and 82305416)Shanghai Key Laboratory of Acupuncture Mechanism and Acupoint Function(No.21DZ2271800)+1 种基金Shanghai Municipal Science and Technology Commission(No.23YF1418300)Scientific Research Project on Traditional Chinese Medicine of Shanghai Municipal Health Commission—Youth Guidance Category(No.2022QN018).
文摘Objective The analgesic effect of acupuncture has been widely accepted.Nevertheless,the mechanism behind its analgesic effect remains elusive,thus impeding the progress of research geared toward enhancing the analgesic effect of acupuncture.This paper investigated the role of acupuncture needle surface textures on acupuncture’s analgesic effect by creating four experimental acupuncture needles with different patterns of surface augmentation.Methods Four types of acupuncture needles with different surface textures(the lined needle,circle needle,sandpaper needle,and threaded needle)were designed.Additionally,the force/torque measurement system used a robot arm and mechanical sensor to measure the force on the needle during insertion and manipulation.To perform acupuncture analgesia experiments,four experimental acupuncture needles and a normal needle were inserted into the Zusanli(ST36)acupoint of rats with inflammatory pain.By comparing the force and torque and the analgesic efficacy of the different acupuncture needles,these experiments tested the role of acupuncture needle body texture on acupuncture analgesia.Results The analgesic effects of different acupuncture needle body textures varied.Specifically,the force required to penetrate the skin with the lined needle was not greater than that for the normal needle;however,the needle with inscribed circles and the sandpaper-roughened needle both required greater force for insertion.Additionally,the torque of the lined needle reached 2×10^(-4)N·m under twisting manipulation,which was four times greater the torque of a normal needle(5×10^(-5)N·m).Furthermore,the lined needle improved pain threshold and mast cell degranulation rate compared to the normal needle.Conclusion Optimizing the texture of acupuncture needles can enhance acupuncture analgesia.The texture of our experimental acupuncture needles had a significant impact on the force needed to penetrate the skin and the torque needed to manipulate the needle;it was also linked to variable analgesic effects.This study provides a theoretical basis for enhancing the analgesic efficacy of acupuncture through the modification of needles and promoting the development of acupuncture therapy.
文摘This paper introduces part of the content in the association standard,T/CAAM0002–2020 Nomenclature and Location of Acupuncture Points for Laboratory Animals Part 2:Rat.This standard was released by the China Association of Acupuncture and Moxibustion on May 15,2020,implemented on October 31,2020,and published by Standards Press of China.The standard was drafted by the Institute of Acupuncture and Moxibustion,China Academy of Chinese Medical Sciences,and the Nanjing University of Chinese Medicine.Principal draftsmen:Xiang-hong JING and Xing-bang HUA.Participating draftsmen:Wan-Zhu BAI,Bin XU,Dong-sheng XU,Yi GUO,Tie-ming MA,Xin-jun WANG,and Sheng-feng LU.
文摘Despite advances in surgery,chemotherapy,and radiotherapy,the treatment of colorectal cancer(CRC)requires more personalized approaches based on tumor biology and molecular profiling.While some relevant mutations have been associated with differential response to immunotherapy,such as RAS and BRAF mutations limiting response to anti-epithelial growth factor receptor drugs or microsatellite instability predisposing susceptibility to immune checkpoint inhibitors,the role of inflammation in dictating tumor progression and treatment response is still under investigation.Several inflammatory biomarkers have been identified to guide patient prognosis.These include the neutrophil-lymphocyte ratio,Glasgow prognostic score(GPS)and its modified version,lymphocyte-Creactive protein ratio,and platelet-lymphocyte ratio.However,these markers are not yet included in the standard clinical management of patients with CRC,and further research is needed to evaluate their efficacy in different patient populations.A recent study by Wang et al,published in the World Journal of Gastroenterology,sheds light on the prognostic significance of pan-immune-inflammation value(PIV)in CRC,particularly concerning primary tumor location.Specifically,the authors found that a high PIV was strongly correlated with worse disease-free survival in patients with left-sided colon cancer,whereas no such association was observed in patients with right-sided colon cancer.Integrating tumor location into the prognostic assessment of CRC may improve our ability to more accurately identify high-risk patients and develop personalized treatment plans that are more likely to improve patient outcomes.
基金Supported by Research Unit of Minimally Invasive Pediatric Surgery on Diagnosis and Treatment,Chinese Academy of Medical Sciences,No.2021RU016.
文摘BACKGROUND Laparoscopic surgery,with the advantage of less trauma,has been predominantly performed to treat pediatric inguinal hernia.However,the traditional three-port laparoscopic surgery remains extremely traumatic for children,whereas singleport laparoscopic surgery causes less damage to children than traditional laparoscopy.However,single-port laparoscopic surgery is more challenging;thus,studies on the effect of its application in pediatric inguinal hernia remain relatively limited.AIM To analyze the association of single-incision laparoscopic herniorrhaphy needle treatment with surgical outcomes,postoperative complications,and serum inflammation in pediatric inguinal hernia.METHODS This retrospective study included 113 pediatric patients with inguinal hernia who underwent surgery at the Children’s Hospital,Capital Institute of Pediatrics,from April 2022 to May 2023.Participants were categorized into the observation group(single-incision laparoscopic herniorrhaphy needle,n=60)and the control group(two-port laparoscopic surgery,n=53).Comparative analyses involved surgical duration,intraoperative blood loss,and length of hospital stay.C-reactive protein(CRP)and white blood cell count(WBC)levels were measured preoperatively and 24 hours postoperatively.Postoperative pain was evaluated with the face,legs,activity,cry,and Consolability scale.Further,the incidence of complications,recurrence,and reoperation rates was assessed.Logistic regression was employed to determine independent risk factors related to poor prognosis.RESULTS The observation group demonstrated significantly reduced intraoperative blood loss and shorter hospitalization compared to the control group(P<0.05).Both groups demonstrated increased CRP and WBC levels postoperatively,but the observation group exhibited significantly lower levels(P<0.05).Further,pain scores at 24 hours postoperatively were significantly lower in the observation group(P<0.05).Additionally,the observation group experienced fewer adverse events,recurrence rates,and reoperations compared to the control group(P<0.05).Logistic regression analysis determined increased postoperative stress markers and surgical technique as independent predictors of recurrence(P<0.05).CONCLUSION Single-incision laparoscopic herniorrhaphy needle treatment for pediatric inguinal hernia exhibits significant efficacy,effectively reduces postoperative complications,ensures a more concealed surgical incision,and promotes faster postoperative recovery than conventional two-port laparoscopy.This approach merits wider application.
基金National Key Research and Development Project:Clinical Evaluation of the Interventional Techniques for Abdominal Obesity(No.2019YFC1710102)。
文摘OBJECTIVE:To assess the efficacy and safety of the Qingyanyin formulated granules(轻燕饮配方颗粒,QYY),press needles(PN),and their combined application in addressing abdominal obesity(AO).This trial aims to offer a more scientifically grounded therapeutic regimen for clinical interventions.METHODS:From March 2021 to July 2021,a multicenter,triple-blind,randomized 2×2 factorial design clinical trial was conducted across 7 centers in 4 major cities within China's mainland.The trial participants were patients diagnosed with AO.The trial followed a 1∶1∶1∶1 random allocation ratio,assigning participants to one of four groups:QYY placebo plus simulated press needles(SPN)(placebo+SPN),QYY plus SPN(QYY+SPN),QYY placebo plus PN(placebo+PN),and QYY plus PN(QYY+PN).The trial participants received treatment for 12 weeks.Observe the changes in waist circumference,body weight,body mass index(BMI),Beck Depression Inventory(BDI),Beck Anxiety Inventory(BAI)scores,and Pittsburgh Sleep Quality Index(PSQI)before and after treatment.RESULTS:The QYY+PN group exhibited significant improvements in waist circumference compared to placebo+PN[Difference=-1.59,95%CI(-3.03,-0.16)]and placebo+SPN groups[Difference=-2.01,95%CI(-3.46,-0.57)].QYY+PN demonstrated a significant advantage over placebo+SPN[Difference=-2.01,95%CI(-3.46,-0.57)],and no statistically significant interaction was observed between the two interventions(P>0.05).In terms of weight and BMI improvements,the QYY+PN,QYY+SPN,and the PN+placebo groups all experienced trending greater reductions in weight compared to the placebo group.In terms of the total scores of PSQI,BAI,and BDI,all four groups exhibited improvements compared to the baseline.Specifically,concerning the change in total PSQI scores,the QYY+PN group exhibited a greater reduction;Regarding the change in total BAI scores,the PN+placebo group demonstrated a greater decrease;As for the change in total BDI scores,the QYY+SPN group displayed a greater reduction.CONCLUSION:This study confirmed that QYY+PN can effectively reduce the waist circumference of patients with AO.Furthermore,the combined approach offers greater benefits than either treatment alone,all without any reported serious adverse events.
基金co-supported by the National Key Research and Development Program of China(No.2024YFE0107900)the National Natural Science Foundation of China(No.62222105)+1 种基金the Natural Science Foundation of Guangdong Province,China(No.2024A1515010235)the 2024 China Unicom Guangdong low-altitude communication and sensing key technology research and digital twin platform research and development project(No.20241890).
文摘Unmanned aerial vehicle(UAV)swarm network consisting of a collection of micro UAVs can be used for many applications.It is well established that packet routing is a fundamental problem to achieve UAV collaboration.However,the highly dynamic nature of UAVs,frequently changing network topologies and security issues,poses significant challenges to packet forwarding in UAV networks.The existing topology-based routing protocols are not well suited in UAV network due to their high controlling overhead or excessive end-to-end delay.Geographic routing is regarded as a promising solution,as it only requires local information.In order to enhance the accuracy and security of geographic routing in highly dynamic UAV network,in this paper,we propose a new predictive geographic(PGeo)routing strategy with location verification.First,a detection mechanism is adopted to recognize malicious UAVs falsifying their location.Then,an accurate average service time of a packet in the medium access control(MAC)layer is derived to assist location prediction.The proposed delay model can provide a theoretical basis for future work,and our simulation results reveal that PGeo outstrips the existing geographic routing protocols in terms of packet delivery ratio in the presence of location spoofing behavior.
文摘BACKGROUND This is a randomized study to compare the diagnostic accuracy of endoscopic ultrasound(EUS)-guided sampling of pancreatic solid lesions obtained with the 22-gauge Franseen(EUS-fine needle biopsy)vs the 22-gauge standard needle(EUS-fine needle aspiration)without rapid onsite evaluation(ROSE),since,in most endoscopy units around the world ROSE is not routinely available.AIM To investigate the accuracy of EUS-guided sampling of pancreatic solid lesions obtained between two different needles without ROSE.METHODS Patients with a solid pancreatic were included.Patients were biopsied in a randomized order.The primary endpoint was the diagnostic sensitivity for pancreatic malignancy(PM).Secondary outcomes were adequacy of the sample,the mean tissue area,the mean tumor area,and the adverse event rate.RESULTS The final diagnosis was pancreatic adenocarcinoma in 38(76%),neuroendocrine tumor in 4(8%),chronic pancreatitis in 3(6%)patients.The sensitivity for PM with Franseen needle was 0.91[95%confidence interval(CI):0.80-0.98],vs 0.8(95%CI:0.67-0.91)(P=0.025)with standard needle.The specificity for PM did not differentiate.The accuracy of the standard needle for PM was 0.80(95%CI:0.66-0.90),and the Franseen group was 0.90(95%CI:0.78-0.97)(P=0.074).The technical success rates for the standard and Franseen needle groups were 94%(95%CI:0.83-0.99)and 100%(95%CI:0.92-1.00),respectively.The mean total tissue area in mm2(SD)was greater in the Franseen group,2.07(0.22)vs 1.16(0.17)(P<0.01).The mean tumor area in mm2(SD)was not different in Franseen group vs standard group,0.42(0.09)vs 0.47(0.09)(P=0.80).There were no adverse events.CONCLUSION The sensitivity for PM and mean total tissue area,was greater in the as compared with standard needle.The mean tumor area did not differ between the groups.
文摘A novel method is developed by utilizing the fractional frequency based multirange rulers to precisely position the passive inter-modulation(PIM)sources within radio frequency(RF)cables.The proposed method employs a set of fractional frequencies to create multiple measuring rulers with different metric ranges to determine the values of the tens,ones,tenths,and hundredths digits of the distance.Among these rulers,the one with the lowest frequency determines the maximum metric range,while the one with the highest frequency decides the highest achievable accuracy of the position system.For all rulers,the metric accuracy is uniquely determined by the phase accuracy of the detected PIM signals.With the all-phase Fourier transform method,the phases of the PIM signals at all fractional frequencies maintain almost the same accuracy,approximately 1°(about 1/360 wavelength in the positioning accuracy)at the signal-to-noise ratio(SNR)of 10 d B.Numerical simulations verify the effectiveness of the proposed method,improving the positioning accuracy of the cable PIM up to a millimeter level with the highest fractional frequency operating at 200 MHz.
基金financially supported by Wuxi Yanping Electronic Technology Co.Ltd.
文摘Semiconductor electronic devices are prone to charge accumulation during production and transportation,which usually causes device breakdown.Ionizers are widely used for electrostatic elimination,and utilizing semiconductor silicon for the discharge needle material in ionizers can effectively prevent metal contamination.To investigate the discharge characteristics of silicon needles and their mode modulation mechanism,this study has established an experimental platform for silicon needle-plate discharge under positive polarity voltage.Discharge pulse parameters and optical signals were measured at varying electrode spacings.The experimental results reveal that silicon needle discharge progresses through four regimes:the spontaneous streamer,the periodic streamer,the cluster streamer,and the glow discharge.Among these,the pulse amplitude is most uniform and stable in the periodic streamer regime.In addition,shorter-gap discharge exhibits higher pulse amplitude and repetition frequency but is easier to transition into the filament regime.The formation process of a single pulse is closely related to the field strength in the ionization region near the needle tip.Hence,parameters such as the pulse rising edge time and falling edge time show minimal variation with voltage.The amount of charge generated per unit time is primarily influenced by the repetition frequency.Consequently,the electrostatic ionizer produces the highest,most stable,and most uniform charges if it operates in the periodic streamer regime.
基金supported by National Natural Science Foundation of China Grant(No.42004040,42474092,U2239204,and 42304145)Natural Science Foundation of Jiangxi Province Grant(20242BAB25190 and 20232BAB213077).
文摘Accurate and rapid determination of source locations is of great significance for surface microseismic monitoring.Traditional methods,such as diffraction stacking,are time-consuming and challenging for real-time monitoring.In this study,we propose an approach to locate microseismic events using a deep learning algorithm with surface data.A fully convolutional network is designed to predict source locations.The input data is the waveform of a microseismic event,and the output consists of three 1D Gaussian distributions representing the probability distribution of the source location in the x,y,and z dimensions.The theoretical dataset is generated to train the model,and several data augmentation methods are applied to reduce discrepancies between the theoretical and field data.After applying the trained model to field data,the results demonstrate that our method is fast and achieves comparable location accuracy to the traditional diffraction stacking location method,making it promising for real-time microseismic monitoring.
基金Major Program of National Social Science Foundation of China,No.21&ZD107。
文摘Data centers operate as physical digital infrastructure for generating,storing,computing,transmitting,and utilizing massive data and information,constituting the backbone of the flourishing digital economy across the world.Given the lack of a consistent analysis for studying the locational factors of data centers and empirical deficiencies in longitudinal investigations on spatial dynamics of heterogeneous data centers,this paper develops a comprehensive analytical framework to examine the dynamic geographies and locational factors of techno-environmentally heterogeneous data centers across Chinese cities in the period of 2006–2021.First,we develop a“supply-demand-environment trinity”analytical framework as well as an accompanying evaluation indicator system with Chinese characteristics.Second,the dynamic geographies of data centers in Chinese cities over the last decades are characterized as spatial polarization in economically leading urban agglomerations alongside persistent interregional gaps across eastern,central,and western regions.Data centers present dual spatial expansion trajectories featuring outward radiation from eastern core urban agglomerations to adjacent peripheries and leapfrog diffusion to strategic central and western digital infrastructural hubs.Third,it is empirically verified that data center construction in Chinese cities over the last decades has been jointly influenced by supply-,demand-,and environment-side locational factors,echoing the efficacy of the trinity analytical framework.Overall,our findings demonstrate the temporal variance,contextual contingency,and attribute-based differentiation of locational factors underlying techno-environmentally heterogeneous data centers in Chinese cities.
