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Design method of high prestressed support for shallow-buried large-span caverns
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作者 JIANG Bei WEI Hua-yong +3 位作者 WANG Qi WANG Ming-zi YIN Chen ZHANG Yan-bo 《Journal of Central South University》 2025年第3期1099-1116,共18页
The surrounding rock is prone to large-scale loosening and failure after the excavation of shallow large-span caverns because of the thin overlying strata and large cross-section span.The rational design of bolt suppo... The surrounding rock is prone to large-scale loosening and failure after the excavation of shallow large-span caverns because of the thin overlying strata and large cross-section span.The rational design of bolt support is very important to the safety control of surrounding rock as a common support means.The control mechanism and design method of bolt support for shallow-buried large-span caverns is carried out.The calculation method of bolt prestress and length based on arched failure and collapsed failure mode is established.The influence mechanism of different influencing factors on the bolt prestress and length is clarified.At the same time,the constant resistance energy-absorbing bolt with high strength and high toughness is developed,and the comparative test of mechanical properties is carried out.On this basis,the design method of high prestressed bolt support for shallow-buried large-span caverns is put forward,and the field test is carried out in Qingdao metro station in China.The monitoring results show that the maximum roof settlement is 6.8 mm after the new design method is adopted,and the effective control of the shallow-buried large-span caverns is realized.The research results can provide theoretical and technical support for the safety control of shallow-buried large-span caverns. 展开更多
关键词 Hoek-Brown strength criterion shallow-buried large-span caverns limit analysis upper bound method high prestress bolt support design method
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A Convolutional Neural Network-Based Deep Support Vector Machine for Parkinson’s Disease Detection with Small-Scale and Imbalanced Datasets
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作者 Kwok Tai Chui Varsha Arya +2 位作者 Brij B.Gupta Miguel Torres-Ruiz Razaz Waheeb Attar 《Computers, Materials & Continua》 2026年第1期1410-1432,共23页
Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using d... Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using deep learning algorithms further enhances performance;nevertheless,it is challenging due to the nature of small-scale and imbalanced PD datasets.This paper proposed a convolutional neural network-based deep support vector machine(CNN-DSVM)to automate the feature extraction process using CNN and extend the conventional SVM to a DSVM for better classification performance in small-scale PD datasets.A customized kernel function reduces the impact of biased classification towards the majority class(healthy candidates in our consideration).An improved generative adversarial network(IGAN)was designed to generate additional training data to enhance the model’s performance.For performance evaluation,the proposed algorithm achieves a sensitivity of 97.6%and a specificity of 97.3%.The performance comparison is evaluated from five perspectives,including comparisons with different data generation algorithms,feature extraction techniques,kernel functions,and existing works.Results reveal the effectiveness of the IGAN algorithm,which improves the sensitivity and specificity by 4.05%–4.72%and 4.96%–5.86%,respectively;and the effectiveness of the CNN-DSVM algorithm,which improves the sensitivity by 1.24%–57.4%and specificity by 1.04%–163%and reduces biased detection towards the majority class.The ablation experiments confirm the effectiveness of individual components.Two future research directions have also been suggested. 展开更多
关键词 Convolutional neural network data generation deep support vector machine feature extraction generative artificial intelligence imbalanced dataset medical diagnosis Parkinson’s disease small-scale dataset
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Seismic response of large-span spatial structures under multi-support and multidimensional excitations including rotational components 被引量:3
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作者 Zhang Jie Li Hongnan Li Chao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第1期141-159,共19页
To achieve rational and precise seismic response predictions of large span spatial structures(LSSSs),the inherent non-uniformity and multidimensionality characteristics of earthquake ground motions should be properly ... To achieve rational and precise seismic response predictions of large span spatial structures(LSSSs),the inherent non-uniformity and multidimensionality characteristics of earthquake ground motions should be properly taken into consideration.However,due to the limitations of available earthquake stations to record seismic rotational components,the effects of rocking and torsional earthquake components are commonly neglected in the seismic analyses of LSSSs.In this study,a newly developed method to extract the rocking and torsion components at any point along the area of a deployed dense array from the translational earthquake recordings is applied to obtain the rotational seismic inputs for a LSSS.The numerical model of an actual LSSS,the Dalian International Conference Center(DICC),is developed to study the influences of multi-support and multidimensional excitations on the seismic responses of LSSSs.The numerical results reveal that the non-uniformity and multidimensionality of ground motion input can considerably affect the dynamic response of the DICC.The specific degree of influence on the overall and local structural displacements,deformations and forces are comprehensively investigated and discussed. 展开更多
关键词 large-span spatial structures seismic responses multi-support MULTIDIMENSIONAL rotational components
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In Situ Experiments on Supporting Load Effect of Large-span Deep Tunnels in Hard Rock 被引量:4
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作者 HE Ben-guo ZHU Yong-quan +2 位作者 SUN Ming-lei LIU Hong-yan ZHANG Zhi-qiang 《Journal of Mountain Science》 SCIE CSCD 2013年第6期1125-1136,共12页
A section of the Nanliang high speed railway tunnel on Shijiazhuang-Taiyuan high-speed passenger railway line in China was instrumented and studied for its mechanical properties and performances. The cross section for... A section of the Nanliang high speed railway tunnel on Shijiazhuang-Taiyuan high-speed passenger railway line in China was instrumented and studied for its mechanical properties and performances. The cross section for the tunnel was300 m2and is classified as the largest cross section for railway tunnels in China. Through in situ experimental studies, mechanistic properties of the tunnel were identified, including the surrounding rock pressure, convergences along tunnel perimeter and safety of primary support and lining structure.Based on the field measured data, the surrounding rock pressure demand for large-span deep tunnel in hard rock is recommended as double peak type in the vertical direction and fold line type was recommended for horizontal pressure. The results suggested that Promojiyfakonov's theory was most close to the monitored value. Specific recommendations were also generated for the use of bolts in tunnel structures.Numerical simulation was used to evaluate the safety of the tunnel and it confirmed that the current design can satisfy the requirement of the current code. 展开更多
关键词 large-span tunnel Railway tunnel Surrounding rock pressure Load distribution In situ experiment
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Parameter analysis of anchor bolt support for large-span and jointed rock mass 被引量:5
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作者 李夕兵 周子龙 +1 位作者 李启月 胡柳青 《Journal of Central South University of Technology》 EI 2005年第4期483-487,共5页
In order to obtain the optimal parameters of anchor bolt supporting system for large-span and jointed rock mass in Kaiyang Phosphor Mine, it is expensive and unavailable with the method of in-situ experiments. This pa... In order to obtain the optimal parameters of anchor bolt supporting system for large-span and jointed rock mass in Kaiyang Phosphor Mine, it is expensive and unavailable with the method of in-situ experiments. This paper describes a numerical modeling with discrete element method for the supporting effects of different type of anchor bolts. The anchor bolts with variant length of 0.5m, 0.8m, 1.0m, diameter of 10mm, 15mm, 20mm, setting spacing of 3.0m, 2.5m, 2.0m, and setting angle of 10°, 20°, 30°, are simulated respectively. The results show that there exist optimal parameters of anchor bolt support for large-span and jointed rock mass. For the bolt support of the concerning, the optimal length is 2.53.5m, the diameter is 2535mm, the spacing is 0.50.6m, and the setting angle is 105°. 展开更多
关键词 jointed rock mass anchor bolt support optimal parameter
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Bolt Supporting of Large-Span Soft Rock Roadway in Shaqu Colliery
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作者 汤雷 付国彬 +5 位作者 陆士良 路彪 江合 穆华平 郭靖 范家文 《International Journal of Mining Science and Technology》 SCIE EI 1998年第2期122-126,共5页
The instability of trapezoidal Ⅰ-steel support is analysed for the compound roof of main coal seam in Shaqu Colliery, and the mechanism of bolt supporting is studied. A scheme of bolt supporting has been given and pu... The instability of trapezoidal Ⅰ-steel support is analysed for the compound roof of main coal seam in Shaqu Colliery, and the mechanism of bolt supporting is studied. A scheme of bolt supporting has been given and put into practice, remarkable technical and economic benefits have been got. 展开更多
关键词 LARGE SPAN COMPOUND ROOF BOLT supportING mechanism
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Research on the random seismic response analysis for multi- and large-span structures to multi-support excitations 被引量:3
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作者 Zhao Bo Wang Yuanqing +3 位作者 Chen Zhihua Shi Yongjiu Jiang Yang Wang Yihong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2015年第3期527-538,共12页
The pseudo excitation method(PEM) has been improved into a more practical form,on which the analytic formulae of seismic response power spectral density(PSD) of simplified large-span structural models have been derive... The pseudo excitation method(PEM) has been improved into a more practical form,on which the analytic formulae of seismic response power spectral density(PSD) of simplified large-span structural models have been derived.The analytic formulae and numerical computing results of seismic response PSD have been derived to study the mechanism of multi-support excitation effects,such as the wave-passage effect and incoherence effect,for the seismic response of multiand large-span structures.By using a multi-span truss as an example,the influence of multi-support excitation effects on the seismic response of such structures is studied. 展开更多
关键词 random seismic response multi-support excitations
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Joint Estimation of SOH and RUL for Lithium-Ion Batteries Based on Improved Twin Support Vector Machineh 被引量:1
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作者 Liyao Yang Hongyan Ma +1 位作者 Yingda Zhang Wei He 《Energy Engineering》 EI 2025年第1期243-264,共22页
Accurately estimating the State of Health(SOH)and Remaining Useful Life(RUL)of lithium-ion batteries(LIBs)is crucial for the continuous and stable operation of battery management systems.However,due to the complex int... Accurately estimating the State of Health(SOH)and Remaining Useful Life(RUL)of lithium-ion batteries(LIBs)is crucial for the continuous and stable operation of battery management systems.However,due to the complex internal chemical systems of LIBs and the nonlinear degradation of their performance,direct measurement of SOH and RUL is challenging.To address these issues,the Twin Support Vector Machine(TWSVM)method is proposed to predict SOH and RUL.Initially,the constant current charging time of the lithium battery is extracted as a health indicator(HI),decomposed using Variational Modal Decomposition(VMD),and feature correlations are computed using Importance of Random Forest Features(RF)to maximize the extraction of critical factors influencing battery performance degradation.Furthermore,to enhance the global search capability of the Convolution Optimization Algorithm(COA),improvements are made using Good Point Set theory and the Differential Evolution method.The Improved Convolution Optimization Algorithm(ICOA)is employed to optimize TWSVM parameters for constructing SOH and RUL prediction models.Finally,the proposed models are validated using NASA and CALCE lithium-ion battery datasets.Experimental results demonstrate that the proposed models achieve an RMSE not exceeding 0.007 and an MAPE not exceeding 0.0082 for SOH and RUL prediction,with a relative error in RUL prediction within the range of[-1.8%,2%].Compared to other models,the proposed model not only exhibits superior fitting capability but also demonstrates robust performance. 展开更多
关键词 State of health remaining useful life variational modal decomposition random forest twin support vector machine convolutional optimization algorithm
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Quantitative principles of dynamic interaction between rock support and surrounding rock in rockburst roadways 被引量:3
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作者 Lianpeng Dai Dingjie Feng +4 位作者 Yishan Pan Aiwen Wang Ying Ma Yonghui Xiao Jianzhuo Zhang 《International Journal of Mining Science and Technology》 2025年第1期41-55,共15页
Rockbursts, which mainly affect mining roadways, are dynamic disasters arising from the surrounding rock under high stress. Understanding the interaction between supports and the surrounding rock is necessary for effe... Rockbursts, which mainly affect mining roadways, are dynamic disasters arising from the surrounding rock under high stress. Understanding the interaction between supports and the surrounding rock is necessary for effective rockburst control. In this study, the squeezing behavior of the surrounding rock is analyzed in rockburst roadways, and a mechanical model of rockbursts is established considering the dynamic support stress, thus deriving formulas and providing characteristic curves for describing the interaction between the support and surrounding rock. Design principles and parameters of supports for rockburst control are proposed. The results show that only when the geostress magnitude exceeds a critical value can it drive the formation of rockburst conditions. The main factors influencing the convergence response and rockburst occurrence around roadways are geostress, rock brittleness, uniaxial compressive strength, and roadway excavation size. Roadway support devices can play a role in controlling rockburst by suppressing the squeezing evolution of the surrounding rock towards instability points of rockburst. Further, the higher the strength and the longer the impact stroke of support devices with constant resistance, the more easily multiple balance points can be formed with the surrounding rock to control rockburst occurrence. Supports with long impact stroke allow adaptation to varying geostress levels around the roadway, aiding in rockburst control. The results offer a quantitative method for designing support systems for rockburst-prone roadways. The design criterion of supports is determined by the intersection between the convergence curve of the surrounding rock and the squeezing deformation curve of the support devices. 展开更多
关键词 Deep roadway ROCKBURST Dynamic interaction Rock support Surrounding rock Rockburst control
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Support electron inductive effect of Pd-Mn/Ni foam catalyst for robust electrocatalytic hydrodechlorination 被引量:1
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作者 Junxi Li Chao Feng +2 位作者 Chong Chen Yuan Pan Yunqi Liu 《Journal of Environmental Sciences》 2025年第3期288-300,共13页
Structural regulation of Pd-based electrocatalytic hydrodechlorination(EHDC)catalyst for constructing high-efficient cathode materials with low noble metal content and high atom utilization is crucial but still challe... Structural regulation of Pd-based electrocatalytic hydrodechlorination(EHDC)catalyst for constructing high-efficient cathode materials with low noble metal content and high atom utilization is crucial but still challenging.Herein,a support electron inductive effect of Pd-Mn/Ni foam catalyst was proposed via in-situ Mn doping to optimize the electronic structure of the Ni foam(NF),which can inductive regulation of Pd for improving the EHDC performance.The mass activity and current efficiency of Pd-Mn/NF catalyst are 2.91 and 1.34 times superior to that of Pd/NF with 2,4-dichlorophenol as model compound,respectively.The Mn-doped interlayer optimized the electronic structure of Pd by bringing the d-state closer to the Fermi level than Pd on the NF surface,which optimizied the binding of EHDC intermediates.Additionally,the Mn-doped interlayer acted as a promoter for generating H∗and accelerating the EHDC reaction.This work presents a simple and effective regulation strategy for constructing high-efficient cathode catalyst for the EHDC of chlorinated organic compounds. 展开更多
关键词 PALLADIUM Structural Regulation Electrocatalytic hydrodechlorination support electron inductive effect
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A Support Vector Machine(SVM)Model for Privacy Recommending Data Processing Model(PRDPM)in Internet of Vehicles
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作者 Ali Alqarni 《Computers, Materials & Continua》 SCIE EI 2025年第1期389-406,共18页
Open networks and heterogeneous services in the Internet of Vehicles(IoV)can lead to security and privacy challenges.One key requirement for such systems is the preservation of user privacy,ensuring a seamless experie... Open networks and heterogeneous services in the Internet of Vehicles(IoV)can lead to security and privacy challenges.One key requirement for such systems is the preservation of user privacy,ensuring a seamless experience in driving,navigation,and communication.These privacy needs are influenced by various factors,such as data collected at different intervals,trip durations,and user interactions.To address this,the paper proposes a Support Vector Machine(SVM)model designed to process large amounts of aggregated data and recommend privacy preserving measures.The model analyzes data based on user demands and interactions with service providers or neighboring infrastructure.It aims to minimize privacy risks while ensuring service continuity and sustainability.The SVMmodel helps validate the system’s reliability by creating a hyperplane that distinguishes between maximum and minimum privacy recommendations.The results demonstrate the effectiveness of the proposed SVM model in enhancing both privacy and service performance. 展开更多
关键词 support vector machine big data IoV PRIVACY-PRESERVING
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Comprehensive influence of individualized nutrition support and nursing strategy on rehabilitation of patients with liver cancer after operation 被引量:1
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作者 Xue-Li Zhang Hai-Yan Ma 《World Journal of Gastrointestinal Surgery》 2025年第2期136-144,共9页
BACKGROUND Hepatocellular carcinoma ranks among the most prevalent malignant neoplasms.Surgical intervention constitutes a critical therapeutic approach for this condition.Nonetheless,postoperative recovery is frequen... BACKGROUND Hepatocellular carcinoma ranks among the most prevalent malignant neoplasms.Surgical intervention constitutes a critical therapeutic approach for this condition.Nonetheless,postoperative recovery is frequently influenced by the patient's nutritional status and the quality of nursing care provided.AIM To examine the comprehensive impact of personalized nutritional support and nursing strategies on the postoperative rehabilitation of patients with liver cancer.METHODS In this study,a retrospective comparative analysis was conducted involving 60 post-operative liver cancer patients.The subjects were selected as subjects and divided into two groups based on differing nursing interventions,with each group comprising 30 patients.The control group received standard nutritional support and care,whereas the experimental group received individualized nutritional support and nursing strategies.The study aimed to evaluate the impact of individualized nutrition by comparing the rehabilitation indices,nutritional status,quality of life(QoL),and complication rates between the two groups.RESULTS The results showed that the recovery index of the experimental group was significantly better than that of the control group 2 weeks after surgery,and the average liver function recovery index of the experimental group was 85.significantly higher than that of the control group(73.67±7.19).In terms of nutritional status,the serum albumin level and body weight stabilization rate of the experimental group were also significantly higher than those of the control group,which were 42.33±2.4 g/L and 93.3%,respectively,compared with 36.01±3.85 g/L and 76.7%of the control group.In addition,the average QoL score of the experimental group was 84.66±3.7 points,which was significantly higher than that of the control group(70.92±4.28 points).At the psychological level,the average anxiety score of the experimental group was 1.17±0.29,and the average depression score was 1.47±0.4,which were significantly lower than the 2.26±0.42 and 2.57±0.45 of the control group.This showed that patients in the experimental group were better relieved of anxiety and depression under the individualized nutrition support and nursing strategy.More importantly,the complication rate in the experimental group was only 10%,much lower than the 33.3%in the control group.CONCLUSION Personalized nutritional support and tailored nursing strategies significantly enhance the postoperative rehabilitation of liver cancer patients.Consequently,it is recommended to implement and advocate for these individualized approaches to improve both the recovery outcomes and QoL for these patients. 展开更多
关键词 Liver cancer After surgery Individualized nutritional support Nursing strategy Rehabilitation effect
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Catalyst–Support Interaction in Polyaniline‑Supported Ni_(3)Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable Zn‑Air Batteries
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作者 Xiaohong Zou Qian Lu +8 位作者 Mingcong Tang Jie Wu Kouer Zhang Wenzhi Li Yunxia Hu Xiaomin Xu Xiao Zhang Zongping Shao Liang An 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期176-190,共15页
Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3... Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe oxide.It is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe oxide.Considering the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts. 展开更多
关键词 Catalyst-support interaction supported catalysts HETEROINTERFACE Oxygen evolution reaction Zn-air batteries
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Analysis of wind-induced vibration response characteristics of multispan double-layer cable photovoltaic support structure 被引量:2
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作者 ZOU Lianghao WANG Jian +2 位作者 SONG Jie ZHOU Rui WANG Hao 《Journal of Southeast University(English Edition)》 2025年第1期37-43,共7页
To investigate the wind⁃induced vibration re⁃sponse characteristics of multispan double⁃layer cable photo⁃voltaic(PV)support structures,wind tunnel tests using an aeroelastic model were carried out to obtain the wind⁃... To investigate the wind⁃induced vibration re⁃sponse characteristics of multispan double⁃layer cable photo⁃voltaic(PV)support structures,wind tunnel tests using an aeroelastic model were carried out to obtain the wind⁃induced vibration response data of a three⁃span four⁃row double⁃layer cable PV support system.The wind⁃induced vibration characteristics with different PV module tilt angles,wind speeds,and wind direction angles were analyzed.The results showed that the double⁃layer cable large⁃span flexible PV support can effectively control the wind⁃induced vibration response and prevent the occur⁃rence of flutter under strong wind conditions.The maxi⁃mum value of the wind⁃induced vibration displacement of the flexible PV support system occurs in the windward first row.The upstream module has a significant shading effect on the downstream module,with a maximum effect of 23%.The most unfavorable wind direction angles of the structure are 0°and 180°.The change of the wind direction angle in the range of 0°to 30°has little effect on the wind vi⁃bration response.The change in the tilt angle of the PV modules has a greater impact on the wind vibration in the downwind direction and a smaller impact in the upwind di⁃rection.Special attention should be paid to the structural wind⁃resistant design of such systems in the upwind side span. 展开更多
关键词 double⁃layer cable photovoltaic support aero⁃elastic model wind tunnel test wind⁃induced vibration re⁃sponse
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Impact of Handshake and Information Support on Patients’ Physiological and Psychological States before Anesthesia Induction for Laparoscopic Cholecystectomy
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作者 Yi Liu Jing Wang +3 位作者 Xiangying Pi Zumei Gao Xiaohui Li Qian Sun 《Journal of Biosciences and Medicines》 2025年第2期58-66,共9页
Objective: This study evaluates the impact of handshake and information support on patients’ outcomes during laparoscopic cholecystectomy. It examines the effects on their physiological and psychological responses an... Objective: This study evaluates the impact of handshake and information support on patients’ outcomes during laparoscopic cholecystectomy. It examines the effects on their physiological and psychological responses and overall satisfaction with nursing care. Methods: A total of 84 patients scheduled for laparoscopic cholecystectomy were selected through convenient sampling and randomly assigned to either the control group or the intervention group using a random number table. Each group consisted of 42 patients. The control group received standard surgical nursing care. In addition to standard care, the intervention group received handshake and information support from the circulating nurse before anesthesia induction. Vital signs were recorded before surgery and before anesthesia induction. Anxiety levels were measured using the State-Trait Anxiety Inventory (STAI) and the State-Anxiety Inventory (S-AI), while nursing satisfaction was assessed using a numerical rating scale. Results: No significant differences were found between the two groups in systolic and diastolic blood pressures before surgery and anesthesia induction (P > 0.05). However, there was a significant difference in heart rate before anesthesia induction (P Conclusion: Providing handshake and information support before anesthesia induction effectively reduces stress, alleviates anxiety, and enhances comfort and satisfaction among patients undergoing laparoscopic cholecystectomy. 展开更多
关键词 HANDSHAKE Information support Anesthesia Induction Preoperative Anxiety
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Tuning support morphology to control alloy over PtCo/γ-Al_(2)O_(3) for the preferential oxidation of CO
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作者 SONG Lichuan ZHONG Liding +3 位作者 SHEN Jia LOU Yake GUO Yun WANG Li 《燃料化学学报(中英文)》 北大核心 2025年第1期96-105,共10页
The preferential oxidation of CO(CO-PROX)reaction is a cost-effective method for eliminating trace amounts of CO from the fuel H2.Pt-based catalysts have been extensively studied for COPROX,with their activity influen... The preferential oxidation of CO(CO-PROX)reaction is a cost-effective method for eliminating trace amounts of CO from the fuel H2.Pt-based catalysts have been extensively studied for COPROX,with their activity influenced by the morphology of the support.Hydrothermal synthesis was employed to produce different morphologies ofγ-Al_(2)O_(3):flower-likeγ-Al_(2)O_(3)(f)exposing(110)crystal faces,sheet-likeγ-Al_(2)O_(3)(s)revealing(100)crystal faces,and rod-likeγ-Al_(2)O_(3)(r)displaying(111)crystal faces,followed by loading PtCo nanoparticles.The exposed crystal faces of the support impact the alloying degree of the PtCo nanoparticles,and an increase in the alloying degree correlates with enhanced catalyst reactivity.Pt_(3)Co intermetallic compounds were identified onγ-Al_(2)O_(3)(f)exposing(110)crystal faces,and PtCo/γ-Al_(2)O_(3)(f)showed high catalytic activity in the CO-PROX reaction,achieving 100%CO conversion across a broad temperature range of 50−225°C.In contrast,only partial alloying of PtCo was observed onγ-Al_(2)O_(3)(s).Furthermore,no alloying between Pt and Co occurred in PtCo/γ-Al_(2)O_(3)(r),resulting in a reaction rate at 50°C that was merely 11%of that of PtCo/γ-Al_(2)O_(3)(f).The formation of Pt3Co intermetallic compounds led to a more oxidized state of Pt,which significantly diminished the adsorption of CO on Pt and augmented the active oxygen species,thereby facilitating the selective oxidation of CO. 展开更多
关键词 PtCo catalysts γ-Al_(2)O_(3) support morphology CO-PROX
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A Study on the Current Situation of Supportive Care Needs and Influencing Factors of Postoperative Patients with Muscle-Invasive Bladder Cancer
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作者 Xue Hu Shangkun Zhang +2 位作者 Qian Sun Juan Zhou Xia Pan 《Journal of Biosciences and Medicines》 2025年第2期357-368,共12页
Objective: To explore the current status and influencing factors of supportive care needs in patients with muscle-invasive bladder cancer after surgery, and to provide a reference for the development of targeted inter... Objective: To explore the current status and influencing factors of supportive care needs in patients with muscle-invasive bladder cancer after surgery, and to provide a reference for the development of targeted intervention strPan ategies. Methods: A general data questionnaire and supportive care needs scale were used to investigate 107 patients with muscle-invasive bladder cancer after surgery. Results: The total score of supportive care needs in patients with muscle-invasive bladder cancer after surgery was (98.48 ± 9.07). Multiple linear regression analysis showed that age, primary caregiver, medical payment method, number of hospitalizations and postoperative time were important influencing factors of supportive care needs in patients with muscle-invasive bladder cancer after surgery (P Conclusion: The supportive care needs of patients with muscle-invasive bladder cancer after surgery are at a low level. Medical staff should identify them early, pay more attention to young patients, patients without medical insurance and patients with multiple hospitalizations, and provide targeted nursing measures to meet their supportive care needs. 展开更多
关键词 Muscle-Invasive Bladder Cancer supportive Care Needs Influencing Factors
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Understanding the Morphology and Mass Transport Resistance of Mesoporous Carbon-Supported PEMFC Based on Modeling Analysis
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作者 Hao Deng Jia Liu Zhong-Jun Hou 《电化学(中英文)》 北大核心 2025年第5期37-61,共25页
Mesoporous carbon supports mitigate platinum(Pt)sulfonic poisoning through nanopore-confined Pt deposition,yet their morphological impacts on oxygen transport remain unclear.This study integrates carbon support morpho... Mesoporous carbon supports mitigate platinum(Pt)sulfonic poisoning through nanopore-confined Pt deposition,yet their morphological impacts on oxygen transport remain unclear.This study integrates carbon support morphology simulation with an enhanced agglomerate model to establish a mathematical framework elucidating pore evolution,Pt utilization,and oxygen transport in catalyst layers.Results demonstrate dominant local mass transport resistance governed by three factors:(1)active site density dictating oxygen flux;(2)ionomer film thickness defining shortest transport path;(3)ionomer-to-Pt surface area ratio modulating practical pathway length.At low ionomer-to-carbon(I/C)ratios,limited active sites elevate resistance(Factor 1 dominant).Higher I/C ratios improve the ionomer coverage but eventually thicken ionomer films,degrading transport(Factors 2–3 dominant).The results indicate that larger carbon particles result in a net increase in local transport resistance by reducing external surface area and increasing ionomer thickness.As the proportion of Pt situated in nanopores or the Pt mass fraction increases,elevated Pt density inside the nanopores exacerbates pore blockage.This leads to the increased transport resistance by reducing active sites,and increasing ionomer thickness and surface area.Lower Pt loading linearly intensifies oxygen flux resistance.The model underscores the necessity to optimize support morphology,Pt distribution,and ionomer content to prevent pore blockage while balancing catalytic activity and transport efficiency.These insights provide a systematic approach for designing high-performance mesoporous carbon catalysts. 展开更多
关键词 Mesoporous carbon support Electrochemical active surface area Platinum coverage Oxygen transport resistance Pore volume distribution
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Influence of Welding Residual Stress on the Structural Behaviour of Large-Span Steel Tube Arch Rib
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作者 Chunling Yan Renzhang Yan +2 位作者 Zhenxiu Zhan Xiyang Chen Yu Han 《Structural Durability & Health Monitoring》 2025年第4期1037-1056,共20页
The steel tube arch rib in a large-span concrete-filled steel tube arch bridge has a large span and diameter,which also leads to a larger weld seam scale.Large-scale welding seams will inevitably cause more obvious we... The steel tube arch rib in a large-span concrete-filled steel tube arch bridge has a large span and diameter,which also leads to a larger weld seam scale.Large-scale welding seams will inevitably cause more obvious welding residual stress(WRS).For the purpose of studying the influence of WRS from large-scale welding seam on the mechanical properties of steel tube arch rib during arch rib splicing,test research and numerical simulation analysis on the WRS in arch rib splicing based on the Guangxi Pingnan Third Bridge,which is the world’s largest span concrete-filled steel tube arch bridge,were conducted in this paper,and the distribution pattern of WRS at the arch rib splicing joint was obtained.Subsequently,the WRS was introduced into the mechanical performance analysis of joints and structures to analyze its effects.The findings reveal that the distribution of WRS in the arch rib is greatly influenced by the rib plate,and the axial WRS in the heat-affected zone are primarily tensile,while the circumferential WRS are distributed in an alternating pattern of tensile and compressive stresses along the circumferential direction of the main tube.Under the influence of WRS,the ultimate bearing capacity of the joint is reduced by 29.4%,the initial axial stiffness is reduced by 4.32%,and the vertical deformation of the arch rib structure is increased by 4.7%. 展开更多
关键词 large-span steel tube arch large-scale welding welding residual stress multi-scale models splicing joint
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Nutrition Support for Patients with Head and Neck Cancer: A Workshop Model for Dysphagia Diet Awareness
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作者 Yuka I. Sumita Ayako Hagino +4 位作者 Mai Murase Mahmoud E. Elbashti Mihoko Haraguchi Mariko Hattori Noriyuki Wakabayashi 《Health》 2025年第2期126-137,共12页
Purpose: In super-aging societies, prosthodontists will have a growing role and will need to improve their nutrition knowledge. This study aimed to evaluate the effectiveness of a workshop-based model for increasing d... Purpose: In super-aging societies, prosthodontists will have a growing role and will need to improve their nutrition knowledge. This study aimed to evaluate the effectiveness of a workshop-based model for increasing dysphagia diet awareness among prosthodontists working with head and neck cancer patients. Methods: The study had a post-intervention design and included 10 maxillofacial prosthetic educators from eight countries who participated in a 120-minute workshop focused on theoretical and practical training in nutrition support for patients with dysphagia. Sessions were held in a specialized restaurant in Tokyo and included lectures, observation of Japanese cooking techniques, hands-on preparation of dysphagia-friendly foods, and cross-cultural comparisons. Knowledge, confidence, and practical application were assessed using a post-workshop questionnaire. Descriptive statistics and thematic analysis were used to evaluate outcomes. Results: Seven of the 10 prosthodontists completed the post-intervention questionnaire. All respondents reported overall satisfaction with the workshop. Session content was regarded as easy to understand by 57.14%, appropriate by 28.57%, and easy by 14.29%. Most respondents (85.71%) were “very satisfied” with the instructors’ explanations, and 100% were “very satisfied” with the workshop’s length and structure;71.42% felt they could apply the knowledge in clinical practice, while 28.58% anticipated challenges. The respondents appreciated the workshop’s focus on dysphagia, particularly in elderly patients, and valued the insights into Japanese dysphagia diets and culture. Conclusions: Workshops on nutrition provide an interactive platform for prosthodontists to enhance their knowledge and improve comprehensive patient care, highlighting the importance for prosthodontists to stay updated on developments in nutrition, particularly in dysphagia. 展开更多
关键词 Dysphagia Diet Awareness Head and Neck Cancer Nutrition support Dental Professionals Workshop Model
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