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Three-dimensional Computational Fluid Dynamics Modeling of Two-phase Flow in a Structured Packing Column 被引量:4
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作者 张小斌 姚蕾 +1 位作者 邱利民 张学军 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第9期959-966,共8页
Characterizing the complex two-phase hydrodynamics in structured packed columns requires a power- ful modeling tool. The traditional two-dimensional model exhibits limitations when one attempts to model the de- tailed... Characterizing the complex two-phase hydrodynamics in structured packed columns requires a power- ful modeling tool. The traditional two-dimensional model exhibits limitations when one attempts to model the de- tailed two-phase flow inside the columns. The present paper presents a three-dimensional computational fluid dy- namics (CFD) model to simulate the two-phase flow in a representative unit of the column. The unit consists of an CFD calculations on column packed with Flexipak 1Y were implemented within the volume of fluid (VOF) mathe- matical framework. The CFD model was validated by comparing the calculated thickness of liquid film with the available experimental data. Special attention was given to quantitative analysis of the effects of gravity on the hy- drodynamics. Fluctuations in the liquid mass flow rate and the calculated pressure drop loss were found to be quali- tatively in agreement with the experimental observations. 展开更多
关键词 structured packing column two-phase flow computational fluid dynamics three-dimension
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The influence of temperature on flow-induced forces on quartz-crystal-microbalance sensors in a Chinese liquor identification electronic-nose: three-dimensional computational fluid dynamics simulation and analysis 被引量:2
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作者 Qiang LI Yu GU Huatao WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第9期1301-1312,共12页
An electronic-nose is developed based on eight quartz-crystal-microbalance (QCM) gas sensors in a sensor box, and is used to detect Chinese liquors at room temperature. Each sensor is a highly-accurate and highly-sens... An electronic-nose is developed based on eight quartz-crystal-microbalance (QCM) gas sensors in a sensor box, and is used to detect Chinese liquors at room temperature. Each sensor is a highly-accurate and highly-sensitive oscillator that has experienced airflow disturbances under the condition of varying room temperatures due to unstable flow-induced forces on the sensors surfaces. The three-dimensional (3D) nature of the airflow inside the sensor box and the interactions of the airflow on the sensors surfaces at different temperatures are studied by computational fluid dynamics (CFD) tools. Higher simulation accuracy is achieved by optimizing meshes, meshing the computational domain using a fine unstructural tetrahedron mesh. An optimum temperature, 30 ℃, is obtained by analyzing the distributions of velocity streamlines and the static pressure, as well as the flow-induced forces over time, all of which may be used to improve the identification accuracy of the electronic-nose for achieving stable and repeatable signals by removing the influence of temperature. 展开更多
关键词 computational fluid dynamics (CFD) TEMPERATURE quartz-crystalmicrobalance (QCM) gas sensor ELECTRONIC NOSE IDENTIFICATION accuracy
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A Multi-Objective Deep Reinforcement Learning Algorithm for Computation Offloading in Internet of Vehicles
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作者 Junjun Ren Guoqiang Chen +1 位作者 Zheng-Yi Chai Dong Yuan 《Computers, Materials & Continua》 2026年第1期2111-2136,共26页
Vehicle Edge Computing(VEC)and Cloud Computing(CC)significantly enhance the processing efficiency of delay-sensitive and computation-intensive applications by offloading compute-intensive tasks from resource-constrain... Vehicle Edge Computing(VEC)and Cloud Computing(CC)significantly enhance the processing efficiency of delay-sensitive and computation-intensive applications by offloading compute-intensive tasks from resource-constrained onboard devices to nearby Roadside Unit(RSU),thereby achieving lower delay and energy consumption.However,due to the limited storage capacity and energy budget of RSUs,it is challenging to meet the demands of the highly dynamic Internet of Vehicles(IoV)environment.Therefore,determining reasonable service caching and computation offloading strategies is crucial.To address this,this paper proposes a joint service caching scheme for cloud-edge collaborative IoV computation offloading.By modeling the dynamic optimization problem using Markov Decision Processes(MDP),the scheme jointly optimizes task delay,energy consumption,load balancing,and privacy entropy to achieve better quality of service.Additionally,a dynamic adaptive multi-objective deep reinforcement learning algorithm is proposed.Each Double Deep Q-Network(DDQN)agent obtains rewards for different objectives based on distinct reward functions and dynamically updates the objective weights by learning the value changes between objectives using Radial Basis Function Networks(RBFN),thereby efficiently approximating the Pareto-optimal decisions for multiple objectives.Extensive experiments demonstrate that the proposed algorithm can better coordinate the three-tier computing resources of cloud,edge,and vehicles.Compared to existing algorithms,the proposed method reduces task delay and energy consumption by 10.64%and 5.1%,respectively. 展开更多
关键词 Deep reinforcement learning internet of vehicles multi-objective optimization cloud-edge computing computation offloading service caching
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DRL-Based Cross-Regional Computation Offloading Algorithm
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作者 Lincong Zhang Yuqing Liu +2 位作者 Kefeng Wei Weinan Zhao Bo Qian 《Computers, Materials & Continua》 2026年第1期901-918,共18页
In the field of edge computing,achieving low-latency computational task offloading with limited resources is a critical research challenge,particularly in resource-constrained and latency-sensitive vehicular network e... In the field of edge computing,achieving low-latency computational task offloading with limited resources is a critical research challenge,particularly in resource-constrained and latency-sensitive vehicular network environments where rapid response is mandatory for safety-critical applications.In scenarios where edge servers are sparsely deployed,the lack of coordination and information sharing often leads to load imbalance,thereby increasing system latency.Furthermore,in regions without edge server coverage,tasks must be processed locally,which further exacerbates latency issues.To address these challenges,we propose a novel and efficient Deep Reinforcement Learning(DRL)-based approach aimed at minimizing average task latency.The proposed method incorporates three offloading strategies:local computation,direct offloading to the edge server in local region,and device-to-device(D2D)-assisted offloading to edge servers in other regions.We formulate the task offloading process as a complex latency minimization optimization problem.To solve it,we propose an advanced algorithm based on the Dueling Double Deep Q-Network(D3QN)architecture and incorporating the Prioritized Experience Replay(PER)mechanism.Experimental results demonstrate that,compared with existing offloading algorithms,the proposed method significantly reduces average task latency,enhances user experience,and offers an effective strategy for latency optimization in future edge computing systems under dynamic workloads. 展开更多
关键词 Edge computing computational task offloading deep reinforcement learning D3QN device-to-device communication system latency optimization
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CUDA‑based GPU‑only computation for efficient tracking simulation of single and multi‑bunch collective effects
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作者 Keon Hee Kim Eun‑San Kim 《Nuclear Science and Techniques》 2026年第1期61-79,共19页
Beam-tracking simulations have been extensively utilized in the study of collective beam instabilities in circular accelerators.Traditionally,many simulation codes have relied on central processing unit(CPU)-based met... Beam-tracking simulations have been extensively utilized in the study of collective beam instabilities in circular accelerators.Traditionally,many simulation codes have relied on central processing unit(CPU)-based methods,tracking on a single CPU core,or parallelizing the computation across multiple cores via the message passing interface(MPI).Although these approaches work well for single-bunch tracking,scaling them to multiple bunches significantly increases the computational load,which often necessitates the use of a dedicated multi-CPU cluster.To address this challenge,alternative methods leveraging General-Purpose computing on Graphics Processing Units(GPGPU)have been proposed,enabling tracking studies on a standalone desktop personal computer(PC).However,frequent CPU-GPU interactions,including data transfers and synchronization operations during tracking,can introduce communication overheads,potentially reducing the overall effectiveness of GPU-based computations.In this study,we propose a novel approach that eliminates this overhead by performing the entire tracking simulation process exclusively on the GPU,thereby enabling the simultaneous processing of all bunches and their macro-particles.Specifically,we introduce MBTRACK2-CUDA,a Compute Unified Device Architecture(CUDA)ported version of MBTRACK2,which facilitates efficient tracking of single-and multi-bunch collective effects by leveraging the full GPU-resident computation. 展开更多
关键词 Code development GPU computing Collective effects
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High-Dimensional Multi-Objective Computation Offloading for MEC in Serial Isomerism Tasks via Flexible Optimization Framework
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作者 Zheng Yao Puqing Chang 《Computers, Materials & Continua》 2026年第1期1160-1177,共18页
As Internet of Things(IoT)applications expand,Mobile Edge Computing(MEC)has emerged as a promising architecture to overcome the real-time processing limitations of mobile devices.Edge-side computation offloading plays... As Internet of Things(IoT)applications expand,Mobile Edge Computing(MEC)has emerged as a promising architecture to overcome the real-time processing limitations of mobile devices.Edge-side computation offloading plays a pivotal role in MEC performance but remains challenging due to complex task topologies,conflicting objectives,and limited resources.This paper addresses high-dimensional multi-objective offloading for serial heterogeneous tasks in MEC.We jointly consider task heterogeneity,high-dimensional objectives,and flexible resource scheduling,modeling the problem as a Many-objective optimization.To solve it,we propose a flexible framework integrating an improved cooperative co-evolutionary algorithm based on decomposition(MOCC/D)and a flexible scheduling strategy.Experimental results on benchmark functions and simulation scenarios show that the proposed method outperforms existing approaches in both convergence and solution quality. 展开更多
关键词 Edge computing offload serial Isomerism applications many-objective optimization flexible resource scheduling
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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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Random State Approach to Quantum Computation of Electronic-Structure Properties
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作者 Yiran Bai Feng Xiong Xueheng Kuang 《Chinese Physics Letters》 2026年第1期89-104,共16页
Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and v... Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials. 展开更多
关键词 periodic materials random state circuit random state quantum algorithms electronic structure properties density states aperiodic materials quantum algorithms quantum computation
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Three-dimensional time-domain full waveform inversion for sound speed and attenuation reconstruction in ultrasound computed tomography
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作者 Zilong Liu Zhijian Tan +1 位作者 Songde Liu Chao Tian 《中国科学技术大学学报》 北大核心 2025年第6期11-20,10,I0001,共12页
Ultrasound computed tomography(USCT)is a noninvasive biomedical imaging modality that offers insights into acoustic properties such as the sound speed(SS)and acoustic attenuation(AA)of the human body,enhancing diagnos... Ultrasound computed tomography(USCT)is a noninvasive biomedical imaging modality that offers insights into acoustic properties such as the sound speed(SS)and acoustic attenuation(AA)of the human body,enhancing diagnostic accuracy and therapy planning.Full waveform inversion(FWI)is a promising USCT image reconstruction method that optimizes the parameter fields of a wave propagation model via gradient-based optimization.However,twodimensional FWI methods are limited by their inability to account for three-dimensional wave propagation in the elevation direction,resulting in image artifacts.To address this problem,we propose a three-dimensional time-domain full waveform inversion algorithm to reconstruct the SS and AA distributions on the basis of a fractional Laplacian wave equation,adjoint field formulation,and gradient descent optimization.Validated by two sets of simulations,the proposed algorithm has potential for generating high-resolution and quantitative SS and AA distributions.This approach holds promise for clinical USCT applications,assisting early disease detection,precise abnormality localization,and optimized treatment planning,thus contributing to better healthcare outcomes. 展开更多
关键词 full waveform inversion ultrasound computed tomography speed of sound acoustic attenuation inverse problems
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Computational complexity of spin-glass three-dimensional(3D)Ising model 被引量:3
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作者 Zhidong Zhang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第9期116-120,共5页
In this work,the computational complexity of a spin-glass three-dimensional(3D)Ising model(for the lattice sizeN=lmn,wherel,m,n are thenumbersof lattice points along three crystallographic directions)is studied.We pro... In this work,the computational complexity of a spin-glass three-dimensional(3D)Ising model(for the lattice sizeN=lmn,wherel,m,n are thenumbersof lattice points along three crystallographic directions)is studied.We prove that an absolute minimum core(AMC)model consisting of a spin-glass 2D Ising model interacting with its nearest neighboring plane,has its computational complexity O(2mn).Any algorithms to make the model smaller(or simpler)than the AMC model will cut the basic element of the spin-glass 3D Ising model and lost many important information of the original model.Therefore,the computational complexity of the spin-glass 3D Ising model cannot be reduced to be less than O(2mn)by any algorithms,which is in subexponential time,superpolynomial. 展开更多
关键词 3D Ising model SPIN-GLASS computational complexity
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Three-dimensional computational fluid dynamics (volume of fluid) modelling coupled with a stochastic discrete phase model for the performance analysis of an invert trap experimentally validated using field sewer solids 被引量:3
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作者 Mohammad Mohsin Deo Raj Kaushal 《Particuology》 SCIE EI CAS CSCD 2017年第4期98-111,共14页
Invert traps are used to trap sewer solids flowing into a sewer drainage system, The performance of the invert trap in an open rectangular channel was experimentally and numerically analysed using field sewer solids c... Invert traps are used to trap sewer solids flowing into a sewer drainage system, The performance of the invert trap in an open rectangular channel was experimentally and numerically analysed using field sewer solids collected from a sewer drain. Experiments showed that the free water surface rises over the central opening (slot) of the invert trap, which reduces the velocity near the slot and allows more sediment to be trapped in comparison with the case for the fixed-lid model (assuming closed conduit flow with a shear-free top wall) used by earlier investigators. This phenomenon cannot be modelled using a closed conduit model as no extra space is provided for the fluctuation of the water surface, whereas this space is provided in the volume of fluid (VOF) model in the form of air space in ANSYS Fluent 14.0 software. Additionally, the zero atmospheric pressure at the free water surface cannot be modelled in a fixed-lid model. In the present study, experimental trap efflciencies of the invert trap using field sewer solids were fairly validated using a three-dimensional computational fluid dynamics model (VOF model) coupled with a stochastic discrete phase model. The flow field (i.e., velocities) predicted by the VOF model were compared with experimental velocities obtained employing particle image velocimetry. The water surface profile above the invert trap predicted by the VOF model was found to be in good agreement with the experimentally measured profile. The present study thus showed that the VOF model can be used with the stochastic discrete phase model to well predict the performance of invert traps. 展开更多
关键词 computational fluid dynamics mode Invert trap Sedimentation Trap efficiency Retention ratio Volume of fluid model
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Demonstration of the refined three-dimensional structure of mesoscale eddies and computational error estimates via Lagrangian analysis
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作者 Heqing Yin Haijin Dai +2 位作者 Weimin Zhang Xueyan Zhang Pinqiang Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第7期146-164,共19页
In previous studies,Lagrangian analyses were used to assess large-scale ocean circulation,and the Lagrangian coherent structure could also reveal the evolution of the two-dimensional structure of the mesoscale eddies.... In previous studies,Lagrangian analyses were used to assess large-scale ocean circulation,and the Lagrangian coherent structure could also reveal the evolution of the two-dimensional structure of the mesoscale eddies.However,few studies have demonstrated the three-dimensional structure of the mesoscale eddies via Lagrangian analysis.Compared with previous studies,which investigated the eddy structure via a Eulerian view,we used a Lagrangian view to provide a different perspective to study the eddy structure.An idealized cyclonic mesoscale eddy is built up over a seamount,and it presents downwelling inside the eddy and upwelling alongside the eddy formed within a closed circulation system.This structure is difficult to display via a Eulerian analysis.However,the trajectories of particles can well demonstrate the full cycle:the fluid sank and rotated inside the eddies,converged to the upwelling zone of the bottom layer and returned to the surface through upwelling.We also applied a Lagrangian analysis to a realistic simulation.As a significant phenomenon in the South China Sea,the dipole structure of the anticyclonic eddy(AE)/cyclonic eddy(CE)pair off of central Vietnam has been well studied but mainly at the sea surface.With a Lagrangian analysis,we illustrate the three-dimensional structure of the eddy pair:the fluid sank(rose)and rotated inside the AE(CE).More importantly,the trajectories of the particles suggested that there was no fluid exchange between the two eddies since the strong boundary jet separates them from each other.All the conclusions above have been verified and are supported by the computational error estimate.With a selected time step and integral period,the computational errors always present small values,although they increase with strong divergent and vertical diffusive flow. 展开更多
关键词 mesoscale eddy Lagrangian analysis three-dimensional structure
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Preoperative diagnosis and operative effect of intracranial aneurysm with three-dimensional computed tomography angiography 被引量:11
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作者 Xuxin Zhang Junhong Guan Duo Chen Yongjie Yang Xiangtai Wei 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第4期358-360,共3页
BACKGROUND : Digital subtraction angiography (DSA) is always regarded as the golden standard for diagnosis of intracranial aneurysm; however, the procedure is complex, traumatic, expensive and easy to induce vascul... BACKGROUND : Digital subtraction angiography (DSA) is always regarded as the golden standard for diagnosis of intracranial aneurysm; however, the procedure is complex, traumatic, expensive and easy to induce vascular complication. Three-dimensional computed tomography angiography (3D-CTA) can make up deficiencies of DSA; therefore, it is used in clinical therapy wider and wider. OBJECTIVE : To evaluate the clinical effect of 3D-CTA on disruption and hemorrhage of intracranial aneurysm pre- and post-operation and compare with the effect of DSA. DESIGN : Auto-control contrast observation SETTING : Department of Neurosurgery, Shengjing Hospital of China Medical University PARTICIPANTS : A number of 106 patients with disruption and hemorrhage of intracranial aneurysm were selected from the Department of Neurosurgery, Shengjing Hospital of China Medical University from January 2003 to April 2006. All patients were diagnosed with cranial operation and consent. There were 47 males and 59 females aged from 3-76 years with the mean age of (47±13) years. Among them, 82 patients had extensive subarachnoid hemorrhage (SAH), 7 had hemorrhage at longitudinal fissure, and 17 had hemorrhage at ambiens cistema and lateral fissure. Moreover, intraventricular hematocele was accompanied on 13 patients and hematom on 9 patients. METHODS: (1) 3D-CTA examination: Siemens SOMATOM Sensation 64 CT was used in this study. The thickness was 1 mm and interval of reconstruction was 0.8 mm. Localizing section was plainly scanned as the standard of canthus line. Scan ranged from 30 mm below sella to 50 mm above sella. Non-ion contrast medium of Omnipaque 350 (concentration of iodine was 350 g/L) was inserted into anterior vein of elbow with 18G trochar retained with high-pressured injectoc pum. The speed was 4.5 mL/s and the total volume was 80-100 mL with the means of 90 mL. Scan started at 10-20 s after injection of contrast medium. Original image was dealt with Leonardo workstation and retreated with Syngo software. Volume rendering and maximum intensity projection were used to reconstructed images, (2) All 106 patients suffered from occlusion of aneurysm clamp. Before operation, 3D-CTA was undertaken and DSA was followed. After operation, patients were rechecked with 3D-CTA. MAIN OUTCOME MEASURES: Comparisons between 3D-CTA and DSA. RESULTS : All 106 patients were involved in the final analysis. (1) Examination of 3D-CTA and DSA: Among 118 patients with aneurysm, 110 were checked with 3D-CTA and the detected rate was 93.2% (110/118). Among other 8 cases, 3 were negative and checked again with DSA; 1 had pericallosal aneurysm, 1 ophthalmic aneurysm, and 1 anterior choroidal artery of aneurysm. 3D-CTA results of other 5 cases were suspicious, and then, they were regarded as having aneurysm with DSA. Before operation, correlation among site, body, neck of aneurysm and peripheral anatomic structure were shown sufficiently. After operation, 82 patients were rechecked with 3D-CTA, which was complete occlusion, precise, unobvious constriction, emphraxis or remains as compared with 3D-CTA those pre-operation. (2) Characteristics of 3D-CTA: With multiple vessels and angles, 3D-CTA observed the relationship between aneurysm neck and carried artery and showed thrombosis in cavity of aneurysm, calcification of aneurysm wall and peripheral structure of vessel at the same time. However, DSA could not detect the reactions mentioned above. It could delete image of cranium, simulate image of operative route, eliminate artifact induced by metal, but not distinguish blood stream direction. Meanwhile, posterior communicating artery was always poor during circle of Willis artery showing. CONCLUSION: (1) 3D-CTA is characterized by simple operation and non-invasive showing vascular stereo structure and correlation. Therefore, it is significant for diagnosis and designing plan of operative approach and focal location pre-operation and evaluating effect post-operation. (2) 3D-CTA does not completely replace DSA on the diagnosis of intracranial aneurysm. 展开更多
关键词 Preoperative diagnosis and operative effect of intracranial aneurysm with three-dimensional computed tomography angiography CTA
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THREE-DIMENSIONAL COMPUTED TOMOGRAPHY-GUIDED RADIOFREQUENCY TRIGEMINAL RHIZOTOMY FOR TREATMENT OF IDIOPATHIC TRIGEMINAL NEURALGIA 被引量:5
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作者 Meng Liu Cheng-yuan Wu Yu-guang Liu Hong-wei Wang Fan-gangMeng 《Chinese Medical Sciences Journal》 CAS CSCD 2005年第3期206-209,共4页
Objective To evaluate the effectiveness of three-dimensional computed tomography (3D-CT) guided radiofi'equency trigeminal rhizotomy (RF-TR) in treatment of idiopathic trigeminal neuralgia (1TN). Methods From ... Objective To evaluate the effectiveness of three-dimensional computed tomography (3D-CT) guided radiofi'equency trigeminal rhizotomy (RF-TR) in treatment of idiopathic trigeminal neuralgia (1TN). Methods From 1999 to 2001, 18 patients with ITN were treated with percutaneous controlled RF-TR. Intraoperative 3D-CT scanning was performed to guide the trajectory of the puncture. After correction of the needle tip according to the CT scans and stimulation effects, 2 to 5 lesions were made for a duration of 60-90 seconds at a temperature of 60℃ to 75℃ depending on the pain distribution and the age of patient. The needles located in foramen ovale. Pain alleviated immediately with no serious complication in all patients. The patients were followed up for an average of 31.5 months (range 24-41 months). Acute pain relief was experienced by 17 patients after the procedure, reaching an initial success rate of 94.4%. Early (〈 6 months) pain recurrence was observed in 2 patients (11.1%), whereas late (〉 6 months) recurrence was reported in 3 patients (16.7%). Thirteen patients had complete pain control, with no need for medication thereafter. Five cases experienced partial pain relief, but required medication at a lower dose than in the preoperative period. Conclusion 3D-CT foramen ovale locations can raise the successful rate of puncture, enhance the safety, and reduce the incidence rate of complication. 展开更多
关键词 trigeminal neuralgia radiofrequency trigeminal rhizotomy three-dimensional computed tomograhpy
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Terahertz Three-Dimensional Imaging Based on Computed Tomography with Photonics-Based Noise Source 被引量:4
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作者 周涛 张戎 +3 位作者 姚辰 符张龙 邵棣祥 曹俊诚 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第8期76-78,共3页
Computed tomography has been proven to be useful for non-destructive inspection of structures and materials. We build a three-dimensional imaging system with the photonically generated incoherent noise source and the ... Computed tomography has been proven to be useful for non-destructive inspection of structures and materials. We build a three-dimensional imaging system with the photonically generated incoherent noise source and the Schottky barrier diode detector in the terahertz frequency band (90–140GHz). Based on the computed tomography technique, the three-dimensional image of a ceramic sample is reconstructed successfully by stacking the slices at different heights. The imaging results not only indicate the ability of terahertz wave in the non-invasive sensing and non-destructive inspection applications, but also prove the effectiveness and superiority of the uni-traveling-carrier photodiode as a terahertz source in the imaging applications. 展开更多
关键词 THz Terahertz three-dimensional Imaging Based on computed Tomography with Photonics-Based Noise Source
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Data-Driven Healthcare:The Role of Computational Methods in Medical Innovation 被引量:1
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作者 Hariharasakthisudhan Ponnarengan Sivakumar Rajendran +2 位作者 Vikas Khalkar Gunapriya Devarajan Logesh Kamaraj 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期1-48,共48页
The purpose of this review is to explore the intersection of computational engineering and biomedical science,highlighting the transformative potential this convergence holds for innovation in healthcare and medical r... The purpose of this review is to explore the intersection of computational engineering and biomedical science,highlighting the transformative potential this convergence holds for innovation in healthcare and medical research.The review covers key topics such as computational modelling,bioinformatics,machine learning in medical diagnostics,and the integration of wearable technology for real-time health monitoring.Major findings indicate that computational models have significantly enhanced the understanding of complex biological systems,while machine learning algorithms have improved the accuracy of disease prediction and diagnosis.The synergy between bioinformatics and computational techniques has led to breakthroughs in personalized medicine,enabling more precise treatment strategies.Additionally,the integration of wearable devices with advanced computational methods has opened new avenues for continuous health monitoring and early disease detection.The review emphasizes the need for interdisciplinary collaboration to further advance this field.Future research should focus on developing more robust and scalable computational models,enhancing data integration techniques,and addressing ethical considerations related to data privacy and security.By fostering innovation at the intersection of these disciplines,the potential to revolutionize healthcare delivery and outcomes becomes increasingly attainable. 展开更多
关键词 computational models biomedical engineering BIOINFORMATICS machine learning wearable technology
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Effects of dry-wet cycles on three-dimensional pore structure and permeability characteristics of granite residual soil using X-ray micro computed tomography 被引量:26
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作者 Ran An Lingwei Kong +1 位作者 Xianwei Zhang Chengsheng Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第3期851-860,共10页
Due to seasonal climate alterations,the microstructure and permeability of granite residual soil are easily affected by multiple dry-wet cycles.The X-ray micro computed tomography(micro-CT)acted as a nondestructive to... Due to seasonal climate alterations,the microstructure and permeability of granite residual soil are easily affected by multiple dry-wet cycles.The X-ray micro computed tomography(micro-CT)acted as a nondestructive tool for characterizing the microstructure of soil samples exposed to a range of damage levels induced by dry-wet cycles.Subsequently,the variations of pore distribution and permeability due to drywet cycling effects were revealed based on three-dimensional(3D)pore distribution analysis and seepage simulations.According to the results,granite residual soils could be separated into four different components,namely,pores,clay,quartz,and hematite,from micro-CT images.The reconstructed 3D pore models dynamically demonstrated the expanding and connecting patterns of pore structures during drywet cycles.The values of porosity and connectivity are positively correlated with the number of dry-wet cycles,which were expressed by exponential and linear functions,respectively.The pore volume probability distribution curves of granite residual soil coincide with the χ^(2)distribution curve,which verifies the effectiveness of the assumption of χ^(2)distribution probability.The pore volume distribution curves suggest that the pores in soils were divided into four types based on their volumes,i.e.micropores,mesopores,macropores,and cracks.From a quantitative and visual perspective,considerable small pores are gradually transformed into cracks with a large volume and a high connectivity.Under the action of dry-wet cycles,the number of seepage flow streamlines which contribute to water permeation in seepage simulation increases distinctly,as well as the permeability and hydraulic conductivity.The calculated hydraulic conductivity is comparable with measured ones with an acceptable error margin in general,verifying the accuracy of seepage simulations based on micro-CT results. 展开更多
关键词 Granite residual soil Dry-wet cycle X-ray micro computed tomography(micro-CT) three-dimensional(3D)pore distribution Seepage simulations PERMEABILITY
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Thoracoscopic segmentectomy assisted by three-dimensional computed tomography bronchography and angiography for lung cancer in a patient living with situs inversus totalis: A case report 被引量:2
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作者 Yun-Jiang Wu Yang Bao Ya-Li Wang 《World Journal of Clinical Cases》 SCIE 2019年第22期3844-3850,共7页
BACKGROUND Situs inversus totalis(SIT)is a rare congenital condition that is characterized by a complete mirror image of the typical arrangement of the thoracic and abdominal viscera.Performing thoracoscopic segmentec... BACKGROUND Situs inversus totalis(SIT)is a rare congenital condition that is characterized by a complete mirror image of the typical arrangement of the thoracic and abdominal viscera.Performing thoracoscopic segmentectomy for a patient with lung cancer and SIT is an extremely skilled and challenging surgical procedure.CASE SUMMARY A 41-year old woman with a medical history of dextrocardia since childhood was admitted to our hospital with a mixed ground-glass opacity(mGGO)in her left lung field,discovered by computed tomography during her health checkup.In order to facilitate surgical orientation,three-dimensional computed tomography bronchography and angiography(3D-CTBA)was preoperatively carried out.The result of 3D-CTBA was consistent with the diagnosis of SIT and an mGGO in the posterior segment of the left upper lobe(LS2).Surgery was conducted in accordance with preoperative 3D-CTBA and designed surgical procedure,combined with intraoperative navigation.Final pathological examination revealed in situ adenocarcinoma.The patient’s postoperative condition was uneventful and no complications were observed.CONCLUSION We present the first case of lung cancer in a patient with SIT who successfully underwent thoracoscopic segmentectomy assisted by 3D-CTBA.This is a new technique that covers precise confirmation and dissection of targeted structures and intersegmental demarcation,and can help achieve a meticulous anatomical segmentectomy. 展开更多
关键词 Situs inversus totalis three-dimensional computED tomographybronchography and ANGIOGRAPHY THORACOSCOPIC SEGMENTECTOMY Lung cancer CASEREPORT
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Three-dimensional computed tomography mapping of posterior malleolar fractures 被引量:2
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作者 Qi-Hang Su Juan Liu +5 位作者 Yan Zhang Jun Tan Mei-Jun Yan Kai Zhu Jin Zhang Cong Li 《World Journal of Clinical Cases》 SCIE 2020年第1期29-37,共9页
BACKGROUND Posterior malleolar fractures have been reported to occur in<40%of ankle fractures.AIM To reveal the recurrent patterns and characteristics of posterior malleolar fractures by creating fracture maps of t... BACKGROUND Posterior malleolar fractures have been reported to occur in<40%of ankle fractures.AIM To reveal the recurrent patterns and characteristics of posterior malleolar fractures by creating fracture maps of the posterior malleolar fractures through the use of computed tomography mapping.METHODS A consecutive series of posterior malleolar fractures was used to create threedimensional reconstruction images,which were oriented and superimposed to fit an ankle model template by both aligning specific biolandmarks and reducing reconstructed fracture fragments.Fracture lines were found and traced in order to generate an ankle fracture map.RESULTS This study involved 112 patients with a mean age of 49,comprising 32 pronationexternal rotation grade IV fractures and 80 supination-external rotation grade IV fractures according to the Lauge-Hansen classification system.Three-dimensional maps showed that the posterior ankle fracture fragments in the supinationexternal rotation grade IV group were relatively smaller than those in the pronation-external rotation grade IV group after posterior malleolus fracture.In addition,the distribution analyses on posterior malleolus fracture lines indicated that the supination-external rotation grade IV group tended to have higher linear density but more concentrated and orderly distribution fractures compared to the pronation-external rotation grade IV group.CONCLUSION Fracture maps revealed the fracture characteristics and recurrent patterns of posterior malleolar fractures,which might help to improve the understanding of ankle fracture as well as increase opportunities for follow-up research and aid clinical decision-making. 展开更多
关键词 three-dimensional imaging MAPS Ankle fractures computed tomography
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