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Mechanism of high-preload support based on the NPR anchor cable in layered soft rock tunnels 被引量:1
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作者 SUI Qiru HE Manchao +3 位作者 SHI Mengfan TAO Zhigang ZHAO Feifei ZHANG Xiaoyu 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1403-1418,共16页
The control of large deformation problems in layered soft rock tunnels needs to solve urgently.The roof problem is particularly severe among the deformation issues in tunnels.This study first analyzes the asymmetric d... The control of large deformation problems in layered soft rock tunnels needs to solve urgently.The roof problem is particularly severe among the deformation issues in tunnels.This study first analyzes the asymmetric deformation modes in layered soft rock tunnels with large deformations.Subsequently,we construct a mechanical model under ideal conditions for controlling the roof of layered soft rock tunnels through high preload with the support of NPR anchor cables.The prominent roles of long and short NPR anchor cables in the support system are also analyzed.The results indicate the significance of high preload in controlling the roof of layered soft rock tunnels.The short NPR anchor cables effectively improve the integrity of the stratified soft rock layers,while the long NPR anchor cables effectively mobilize the self-bearing capacity of deep-stable rock layers.Finally,the high-preload support method with NPR anchor cables is validated to have a good effect on controlling large deformations in layered soft rock tunnels through field monitoring data. 展开更多
关键词 Tunnel engineering Soft rock High-preload support NPR anchor cables
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Analysis of the interaction between bolt-reinforced rock and surface support in tunnels based on convergence-confinement method 被引量:2
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作者 Zhenyu Sun Dingli Zhang +2 位作者 Qian Fang Yanjuan Hou Nanqi Huangfu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1936-1951,共16页
To investigate the interaction of the bolt-reinforced rock and the surface support,an analytical model of the convergence-confinement type is proposed,considering the sequential installation of the fully grouted rockb... To investigate the interaction of the bolt-reinforced rock and the surface support,an analytical model of the convergence-confinement type is proposed,considering the sequential installation of the fully grouted rockbolts and the surface support.The rock mass is assumed to be elastic-brittle-plastic material,obeying the linear Mohr-Coulomb criterion or the non-linear Hoek-Brown criterion.According to the strain states of the tunnel wall at bolt and surface support installation and the relative magnitude between the bolt length and the plastic depth during the whole process,six cases are categorized upon solving the problem.Each case is divided into three stages due to the different effects of the active rockbolts and the passive surface support.The fictitious pressure is introduced to quantify the threedimensional(3D)effect of the tunnel face,and thus,the actual physical location along the tunnel axis of the analytical section can be considered.By using the bolt-rock strain compatibility and the rocksurface support displacement compatibility conditions,the solutions of longitudinal tunnel displacement and the reaction pressure of surface support along the tunnel axis are obtained.The proposed analytical solutions are validated by a series of 3D numerical simulations.Extensive parametric studies are conducted to examine the effect of the typical parameters of rockbolts and surface support on the tunnel displacement and the reaction pressure of the surface support under different rock conditions.The results show that the rockbolts are more effective in controlling the tunnel displacement than the surface support,which should be installed as soon as possible with a suitable length.For tunnels excavated in weak rocks or with restricted displacement control requirements,the surface support should also be installed or closed timely with a certain stiffness.The proposed method provides a convenient alternative approach for the optimization of rockbolts and surface support at the preliminary stage of tunnel design. 展开更多
关键词 Analytical model Longitudinal tunnel displacement Fictitious pressure Active rockbolts Surface support reaction pressure Tunnel design
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Looking up Prescriptions to Treat Infectious Disease:Anti-epidemic Books of Medical Formularies and Epidemic Prevention and Control in the Qing Dynasty
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作者 LIU Xiyang GUO Zhiheng(Translated) 《Chinese Medicine and Culture》 2023年第1期17-32,共16页
Copying,compiling,publishing,disseminating,and referencing anti-epidemic books of medical formularies were common activities during the outbreak of epidemics in the Qing dynasty.Its emergence,motivated by epidemic dis... Copying,compiling,publishing,disseminating,and referencing anti-epidemic books of medical formularies were common activities during the outbreak of epidemics in the Qing dynasty.Its emergence,motivated by epidemic disease again and again,was important component parts of epidemic prevention and control.They played a unique role as media on affairs such as treating patients suffering from infectious diseases,mobilizing peoples to make contributions to anti-epidemic activities,integrating and popularizing knowledge of epidemic prevention.Anti-epidemic books of medical formularies were important to link peoples,things,and substances related with epidemic prevention and control,and were a kind of motivation to actively deal with the infectious disease,control the epidemic,and maintain health.Compared to other common measures,anti-epidemic books of medical formularies participated in many prevention and control practices deeply,which actually built a low cost,spontaneous,dispersed and non-institutional system to respond to epidemic,and the system had characteristics of stronger conductibility,bigger coverage area,and better external benefits. 展开更多
关键词 anti-epidemic books of medical formularies Epidemic prevention and control Knowledge diffusion Medical practice Qing dynasty
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Stability analysis of longwall top-coal caving face in extra-thick coal seams based on an innovative numerical hydraulic support model 被引量:1
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作者 Jun Guo Wenbo Huang +7 位作者 Guorui Feng Jinwen Bai Lirong Li Zi Wang Luyang Yu Xiaoze Wen Jie Zhang Wenming Feng 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期491-505,共15页
The relationship between support and surrounding rock is of great significance to the control of surrounding rock in mining process.In view of the fact that most of the existing numerical simulation methods construct ... The relationship between support and surrounding rock is of great significance to the control of surrounding rock in mining process.In view of the fact that most of the existing numerical simulation methods construct virtual elements and stress servo control to approximately replace the hydraulic support problem,this paper establishes a new numerical model of hydraulic support with the same working characteristics as the actual hydraulic support by integrating numerical simulation software Rhino,Griddle and FLAC3D,which can realize the simulation of different working conditions.Based on this model,the influence mechanism of the supporting strength of hydraulic support on surrounding rock stress regulation and coal stability in front of the top coal caving face in extra thick coal seam were researched.Firstly,under different support intensity,the abutment pressure of the bearing coal and the coal in front of it presents the “three-stage”evolution characteristics.The influence range of support intensity is 15%–30%.Secondly,1.5 MPa is the upper limit of impact that the support strength can have on the front coal failure area.Thirdly,within a displacement range of 2.76 m from the coal wall,a support strength of1.5 MPa provides optimal control of the horizontal displacement of the coal. 展开更多
关键词 Extremely thick coal seam Fully mechanized top coal caving support strength support-surrounding rock interaction
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Network Pharmacology, Molecular Docking and Experimental Exploring Molecular Mechanisms of Yinqiao Anti-Epidemic Formula in Regulating Mucosal Immune System of Respiratory Tract
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作者 Heng XU Fangyuan LI +6 位作者 Guoqiang LIANG Jie YUAN Xiudao SONG Yunhai ZHOU Hui ZHU Yichao YAN Tingting WU 《Agricultural Biotechnology》 CAS 2023年第4期75-84,共10页
[Objectives]To explore the molecular mechanisms of Yinqiao anti-epidemic formula(YQAEF)in regulating mucosal immune system of respiratory tract.[Methods]The active components of YQAEF were obtained from the TCMSP data... [Objectives]To explore the molecular mechanisms of Yinqiao anti-epidemic formula(YQAEF)in regulating mucosal immune system of respiratory tract.[Methods]The active components of YQAEF were obtained from the TCMSP database,and RMIS targets were obtained from the GeneCards database.A"YQAEF components-RMIS targets-pathways"network was constructed by analyzing the above data to screen core targets for molecular docking verification.A mouse model of acute upper respiratory tract infection(AURI)was developed.Based on the experimental models,the key pathway target genes screened by network pharmacology were verified in vivo.[Results]The main active components of YQAEF involved in the regulation of the RMIS included quercetin,acetic acid,and raffinose.Key targets,such as angiotensin-converting enzyme(ACE),galactosidase alpha(GLA),matrix metalloproteinase 2(MMP2),Serpin Family E Member 1(SERPINE1),and myeloperoxidase(MPO)and important viral infection and endocrine resistance signaling pathways were included in the regulation of the RMIS with YQAEF.Molecular docking assays showed that the key targets had good binding activities with the components of YQAEF.Based on the results of network pharmacology,key target proteins in ACE,GLA,MMP2,SERPINE1,and MPO were selected for experimental verification.The results showed that ACE/ACE2 and MPO expressions were increased in the oral and throat mucosa of the AURI mice.Under YQAEF treatment,the expression levels of ACE/ACE2 and MPO were decreased.[Conclusions]This study revealed the mechanism of YQAEF in the regulation of RMIS,which is associated with multiple components,targets,and pathways.Further experiments confirmed that YQAEF interfered with MPO and ACE/ACE2 signaling pathways to regulate the RMIS in the oral and throat mucosa tissue of mice with AURI,and provide a new direction for exploring the potential antiviral mechanism of YQAEF. 展开更多
关键词 Respiratory passage mucosal immune system RMIS Network pharmacology Molecular docking ACE/ACE2 Yinqiao anti-epidemic formula(YQAEF)
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Translocation of telomerase reverse transcriptase coincided with ATP release in postnatal cochlear supporting cells 被引量:1
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作者 Yukai Zhang Keyong Tian +9 位作者 Wei Wei Wenjuan Mi Fei Lu Zhenzhen Liu Qingwen Zhu Xinyu Zhang Panling Geng Jianhua Qiu Yongli Song Dingjun Zha 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1119-1125,共7页
The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechani... The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechanisms responsible for initiating spontaneous ATP release have not been determined.Our previous study revealed that telomerase reverse transcriptase(TERT)is expressed in the basilar membrane during the first postnatal week.Its role in cochlear development remains unclear.In this study,we investigated the expression and role of TERT in postnatal cochlea supporting cells.Our results revealed that in postnatal cochlear Kölliker’s organ supporting cells,TERT shifts from the nucleus into the cytoplasm over time.We found that the TERT translocation tendency in postnatal cochlear supporting cells in vitro coincided with that observed in vivo.Further analysis showed that TERT in the cytoplasm was mainly located in mitochondria in the absence of oxidative stress or apoptosis,suggesting that TERT in mitochondria plays roles other than antioxidant or anti-apoptotic functions.We observed increased ATP synthesis,release and activation of purine signaling systems in supporting cells during the first 10 postnatal days.The phenomenon that TERT translocation coincided with changes in ATP synthesis,release and activation of the purine signaling system in postnatal cochlear supporting cells suggested that TERT may be involved in regulating ATP release and activation of the purine signaling system.Our study provides a new research direction for exploring the spontaneous electrical activity of the cochlea during the early postnatal period. 展开更多
关键词 apoptosis ATP release Ca2+transients COCHLEA mitochondrial function reactive oxygen species spontaneous electrical activity supporting cells
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Correlation Analysis between Self-Disclosure and Social Support in Patients with Breast Cancer
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作者 Yun Ding Liping Zhang +1 位作者 Huiying Qin Lijuan Zhang 《Advances in Breast Cancer Research》 CAS 2024年第4期59-68,共10页
Objective: Describe the status quo of self-disclosure and social support in breast cancer patients and analyze the correlation between them. Methods: General data questionnaire, distress disclosure Index scale and Chi... Objective: Describe the status quo of self-disclosure and social support in breast cancer patients and analyze the correlation between them. Methods: General data questionnaire, distress disclosure Index scale and Chinese version of medical social support scale were used to investigate the correlation between self-disclosure and social support in breast cancer patients by Pearson correlation analysis. Results: 1) The total self-disclosure score was (38.75 ± 9.18);the total score of social support was (70.57 ± 14.04) scores, including emotional information support dimension (28.39 ± 6.06) scores, practical support dimension (15.62 ± 3.31) scores, elastic support dimension (14.85 ± 3.23) scores, and emotional support dimension (11.70 ± 2.56) scores. 2) Self-disclosure was positively correlated with social support (r = 0.433, p Conclusion: Breast cancer patients had a moderate level of self-disclosure, and the higher the level of self-disclosure, the better the social support. It is suggested that improving the self-disclosure level of breast cancer patients can help them obtain more social support. 展开更多
关键词 Breast Cancer SELF-DISCLOSURE Social support
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Cost-effective bifunctional lignin-derived carbon supported tin oxide with efficient production of 5-hydroxymethylfurfural from glucose
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作者 Sien Yan Linhuo Gan +1 位作者 Kui Wang Kang Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第10期154-164,共11页
5-Hydroxymethylfurfural(5-HMF)is one of the important bio-based platform compounds,and the catalytic conversion of glucose to 5-HMF is a highly desirable approach that is receiving increasing attention.Herein,we repor... 5-Hydroxymethylfurfural(5-HMF)is one of the important bio-based platform compounds,and the catalytic conversion of glucose to 5-HMF is a highly desirable approach that is receiving increasing attention.Herein,we reported the synthesis of lignin-derived carbon supported tin oxides(SnOx/LC)catalyst via a two-step hydrothermal-pyrolytic method using wheat straw alkali lignin as a cost-effective carbon source with high carbon content.The key preparation conditions of the catalyst and its catalytic conditions for the conversion of glucose to 5-HMF were investigated,respectively.Results show that under the preparation conditions of tin tetrachloride dosage of 3.0 mmol and pyrolysis temperature of 500 ℃,the optimized catalyst(3.0-SnOx/LC-500)with a high yield of 63.4%exhibits good catalytic performance of 5-HMF yield of 50.1%and reaction selectivity of 86.0%under the optimum conditions of reaction temperature and time of 190 ℃ and 3 h,initial glucose concentration of 10%(mass),3.0-SnOx/LC-500 dosage of 100 mg in a biphasic solvent system of volume ratio of water to tetrahydrofuran of 1:4.In addition,3.0-SnOx/LC-500 exerts an excellent reusability in a five-cycle experiment.Furthermore,SnOx/LC was characterized in detail using X-ray diffraction patterns(XRD),X-ray photoelectron spectroscopy(XPS),Brunauer-Emmett-Teller(BET),ammonia temperature-programmed-desorption(NH3-TPD),pyridine adsorption infrared spectroscopy(Py-FTIR),scanning electron microscope(SEM)and thermal gravimetric analysis(TGA).Results indicate that Brønsted acid sites and Lewis acid sites coexist on 3.0-SnOx/LC-500,and more Sn^(4+),as well as a proper ratio of weak acidity to medium acidity,are conductive to its catalytic performance in glucose-to-5-HMF reaction. 展开更多
关键词 LIGNIN Biomass Catalyst support SELECTIVITY Biphasic solvent system
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Aqueous-phase reforming of hydroxyacetone solution to bio-based H_(2)over supported Pt catalysts
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作者 A.K.K.Vikla K.Koichumanova +1 位作者 Songbo He K.Seshan 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期777-788,共12页
Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction conditions.In this work,t... Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction conditions.In this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 bar.Among them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst stability.Over the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst deactivation.The proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WGS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance. 展开更多
关键词 APR HYDROXYACETONE TOF Bio-based H_(2) support effect
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Critical role of carbon support in metal nanoaggregate facilitating Fe-N-C catalyst for PEM fuel cell application
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作者 Liming Guo Xin Wan +4 位作者 Qingtao Liu Xiaofang Liu Jiaxiang Shang Ronghai Yu Jianglan Shui 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期669-676,I0014,共9页
Metal nanoaggregates can simultaneously enhance the activity and stability of Fe-N-C catalysts in proton-exchange-membrane fuel cells(PEMFC).Previous studies on the relevant mechanism have focused on the direct intera... Metal nanoaggregates can simultaneously enhance the activity and stability of Fe-N-C catalysts in proton-exchange-membrane fuel cells(PEMFC).Previous studies on the relevant mechanism have focused on the direct interaction between FeN_(4)active sites and metal nanoaggregates.However,the role of carbon support that hosts metal nanoaggregates and active sites has been overlooked.Here,a Fe-N-C catalyst encapsulating inactive gold nanoparticles is prepared as a model catalyst to investigate the electronic tuning of Au nanoparticles(NPs)towards the carbon support.Au NPs donate electrons to carbon support,making it rich inπelectrons,which reduces the work function and regulates the electronic configuration of the FeN_(4)sites for an enhanced ORR activity.Meanwhile,the electron-rich carbon support can mitigate the electron depletion of FeN_(4)sites caused by carbon support oxidation,thereby preserving its high activity.The yield and accumulation of H_(2)O_(2)are thus alleviated,which delays the oxidation of the catalyst and benefits the stability.Due to the electron-rich carbon support,the composite catalyst achieves a top-level peak power density of 0.74 W/cm^(2) in a 1.5 bar H_(2)-air PEMFC,as well as the improved stability.This work elucidates the key role of carbon support in the performance enhancement of the FeN-C/metal nanoaggregate composite catalysts for fuel cell application. 展开更多
关键词 Fuel cells Oxygen reduction reaction Fe-N-C Hetero-structure catalyst Carbon support
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Enhanced stability of nitrogen-doped carbon-supported palladium catalyst for oxidative carbonylation of phenol
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作者 Xiaojing Liu Ruohan Zhao +4 位作者 Hao Zhao Zhimiao Wang Fang Li Wei Xue Yanji Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期19-28,共10页
Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and industry.Herein,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticle... Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and industry.Herein,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticles(NPs)on nitrogen-doped carbon;synthesized by using F127 as a stabilizer,as well as chitosan as a carbon and nitrogen source.The Pd/NCF catalyst was efficient and recyclable for oxidative carbonylation of phenol to diphenyl carbonate,exhibiting higher stability than Pd/NC prepared without F127 addition.The hydrogen bond between chitosan(CTS)and F127 was enhanced by F127,which anchored the N in the free amino group,increasing the N content of the carbon material and ensuring that the support could provide sufficient N sites for the deposition of Pd NPs.This process helped to improve metal dispersion.The increased metal-support interaction,which limits the leaching and coarsening of Pd NPs,improves the stability of the Pd/NCF catalyst.Furthermore,density functional theory calculations indicated that pyridine N stabilized the Pd^(2+)species,significantly inhibiting the loss of Pd^(2+)in Pd/NCF during the reaction process.This work provides a promising avenue towards enhancing the stability of nitrogen-doped carbon-supported metal catalysts. 展开更多
关键词 supported Pd catalyst N-doped carbon Amphiphilic triblock copolymer Pyridinic nitrogen STABILITY
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Differentially Private Support Vector Machines with Knowledge Aggregation
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作者 Teng Wang Yao Zhang +2 位作者 Jiangguo Liang Shuai Wang Shuanggen Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期3891-3907,共17页
With the widespread data collection and processing,privacy-preserving machine learning has become increasingly important in addressing privacy risks related to individuals.Support vector machine(SVM)is one of the most... With the widespread data collection and processing,privacy-preserving machine learning has become increasingly important in addressing privacy risks related to individuals.Support vector machine(SVM)is one of the most elementary learning models of machine learning.Privacy issues surrounding SVM classifier training have attracted increasing attention.In this paper,we investigate Differential Privacy-compliant Federated Machine Learning with Dimensionality Reduction,called FedDPDR-DPML,which greatly improves data utility while providing strong privacy guarantees.Considering in distributed learning scenarios,multiple participants usually hold unbalanced or small amounts of data.Therefore,FedDPDR-DPML enables multiple participants to collaboratively learn a global model based on weighted model averaging and knowledge aggregation and then the server distributes the global model to each participant to improve local data utility.Aiming at high-dimensional data,we adopt differential privacy in both the principal component analysis(PCA)-based dimensionality reduction phase and SVM classifiers training phase,which improves model accuracy while achieving strict differential privacy protection.Besides,we train Differential privacy(DP)-compliant SVM classifiers by adding noise to the objective function itself,thus leading to better data utility.Extensive experiments on three high-dimensional datasets demonstrate that FedDPDR-DPML can achieve high accuracy while ensuring strong privacy protection. 展开更多
关键词 Differential privacy support vector machine knowledge aggregation data utility
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The Support Systems and Coping Strategies of Infertile Women Attending the Out-Patient Consultation Unit of CHRACERH Yaoundé, Cameroon: A Cross-Sectional Study
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作者 Emenguele Pascale Mpono Fidelia Mbi Kobenge +3 位作者 Gabrielle Laure Mengne Etienne Belinga Jean Marie Kasia Thomas Obinchemti Egbe 《Open Journal of Obstetrics and Gynecology》 2024年第6期869-887,共19页
Background: Infertility is a complex disorder with significant psycho-social and economic consequences. It globally affects 10% - 15% of couples. In Cameroon, little is known about what women do to overcome the psycho... Background: Infertility is a complex disorder with significant psycho-social and economic consequences. It globally affects 10% - 15% of couples. In Cameroon, little is known about what women do to overcome the psychosocial aspects of the disease. Objectives: This study aimed to identify the support systems and coping strategies of infertile women attending the outpatient consultation unit of the Gynaecological Endoscopic Surgery and Reproductive Teaching Hospital (CHRACERH), Yaoundé, Cameroon. Methods: A hospital-based cross-sectional study was conducted from the 14th of March to the 6th of April 2023 at CHRACERH Yaoundé. A total of 190 participants were recruited using a convenience sampling method. Data regarding socio-demographic characteristics, support systems and coping strategies were collected using a pretested questionnaire. Descriptive and analytic statistics were conducted using SPSS version 25. Results: The mean age of participants was 39.52 ± 7.64 years. The majority 78.9% of participants were workers (public, private sector, or traders) and were Christians 95.8%. The most common source of psychological support was from family 76.8 and husbands 72.63%. Most of the participants 89.5% resorted to prayer and getting busy 48.4% as a coping strategy. There was no statistically significant relationship between coping strategies and psychological disorders p > 0.05. Conclusion: The main support system of participants was family, husband, and friends. Prayer, getting busy and adoption were the most common coping strategies. There is a need for the Ministry of Public Health and other stakeholders to put in place other support systems and coping strategies (FELICIA) used elsewhere and provide adequate health education and infection control to prevent infertility in Cameroon. 展开更多
关键词 INFERTILITY Coping Strategies support Systems Mental Health WOMEN
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Research on the flow stability and noise reduction characteristics of quasi-periodic elastic support skin
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作者 Lu Chen Shao-gang Liu +5 位作者 Dan Zhao Li-qiang Dong Kai Li Shuai Tang Jin Cui Hong Guo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期222-236,共15页
To enhance flow stability and reduce hydrodynamic noise caused by fluctuating pressure,a quasiperiodic elastic support skin composed of flexible walls and elastic support elements is proposed for fluid noise reduction... To enhance flow stability and reduce hydrodynamic noise caused by fluctuating pressure,a quasiperiodic elastic support skin composed of flexible walls and elastic support elements is proposed for fluid noise reduction.The arrangement of the elastic support element is determined by the equivalent periodic distance and quasi-periodic coefficient.In this paper,a dynamic model of skin in a fluid environment is established.The influence of equivalent periodic distance and quasi-periodic coefficient on flow stability is investigated.The results suggest that arranging the elastic support elements in accordance with the quasi-periodic law can effectively enhance flow stability.Meanwhile,the hydrodynamic noise calculation results demonstrate that the skin exhibits excellent noise reduction performance,with reductions of 10 dB in the streamwise direction,11 dB in the spanwise direction,and 10 dB in the normal direction.The results also demonstrate that the stability analysis method can serve as a diagnostic tool for flow fields and guide the design of noise reduction structures. 展开更多
关键词 Flow stability Quasi-period Flexible wall Elastic support element Hydrodynamic noise
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Improved Twin Support Vector Machine Algorithm and Applications in Classification Problems
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作者 Sun Yi Wang Zhouyang 《China Communications》 SCIE CSCD 2024年第5期261-279,共19页
The distribution of data has a significant impact on the results of classification.When the distribution of one class is insignificant compared to the distribution of another class,data imbalance occurs.This will resu... The distribution of data has a significant impact on the results of classification.When the distribution of one class is insignificant compared to the distribution of another class,data imbalance occurs.This will result in rising outlier values and noise.Therefore,the speed and performance of classification could be greatly affected.Given the above problems,this paper starts with the motivation and mathematical representing of classification,puts forward a new classification method based on the relationship between different classification formulations.Combined with the vector characteristics of the actual problem and the choice of matrix characteristics,we firstly analyze the orderly regression to introduce slack variables to solve the constraint problem of the lone point.Then we introduce the fuzzy factors to solve the problem of the gap between the isolated points on the basis of the support vector machine.We introduce the cost control to solve the problem of sample skew.Finally,based on the bi-boundary support vector machine,a twostep weight setting twin classifier is constructed.This can help to identify multitasks with feature-selected patterns without the need for additional optimizers,which solves the problem of large-scale classification that can’t deal effectively with the very low category distribution gap. 展开更多
关键词 FUZZY ordered regression(OR) relaxing variables twin support vector machine
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A Support Data-Based Core-Set Selection Method for Signal Recognition
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作者 Yang Ying Zhu Lidong Cao Changjie 《China Communications》 SCIE CSCD 2024年第4期151-162,共12页
In recent years,deep learning-based signal recognition technology has gained attention and emerged as an important approach for safeguarding the electromagnetic environment.However,training deep learning-based classif... In recent years,deep learning-based signal recognition technology has gained attention and emerged as an important approach for safeguarding the electromagnetic environment.However,training deep learning-based classifiers on large signal datasets with redundant samples requires significant memory and high costs.This paper proposes a support databased core-set selection method(SD)for signal recognition,aiming to screen a representative subset that approximates the large signal dataset.Specifically,this subset can be identified by employing the labeled information during the early stages of model training,as some training samples are labeled as supporting data frequently.This support data is crucial for model training and can be found using a border sample selector.Simulation results demonstrate that the SD method minimizes the impact on model recognition performance while reducing the dataset size,and outperforms five other state-of-the-art core-set selection methods when the fraction of training sample kept is less than or equal to 0.3 on the RML2016.04C dataset or 0.5 on the RML22 dataset.The SD method is particularly helpful for signal recognition tasks with limited memory and computing resources. 展开更多
关键词 core-set selection deep learning model training signal recognition support data
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Development of multi-functional anchorage support dynamic-static coupling performance test system and its application
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作者 Qi Wang Shuo Xu +4 位作者 Bei Jiang Chong Zhang Zhe Sun Jingxuan Liu Cailin Jiao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期339-349,共11页
In underground engineering with complex conditions,the bolt(cable)anchorage support system is in an environment where static and dynamic stresses coexist,under the action of geological conditions such as high stresses... In underground engineering with complex conditions,the bolt(cable)anchorage support system is in an environment where static and dynamic stresses coexist,under the action of geological conditions such as high stresses and strong disturbances and construction conditions such as the application of high prestress.It is essential to study the support components performance under dynamic-static coupling conditions.Based on this,a multi-functional anchorage support dynamic-static coupling performance test system(MAC system)is developed,which can achieve 7 types of testing functions,including single component performance,anchored net performance,anchored rock performance and so on.The bolt and cable mechanical tests are conducted by MAC system under different prestress levels.The results showed that compared to the non-prestress condition,the impact resistance performance of prestressed bolts(cables)is significantly reduced.In the prestress range of 50–160 k N,the maximum reduction rate of impact energy resisted by different types of bolts is 53.9%–61.5%compared to non-prestress condition.In the prestress range of 150–300 k N,the impact energy resisted by high-strength cable is reduced by76.8%–84.6%compared to non-prestress condition.The MAC system achieves dynamic-static coupling performance test,which provide an effective means for the design of anchorage support system. 展开更多
关键词 Anchorage support system Development of test system Dynamic-static coupling test Combined stress
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Nutritional Support under the Neuman Systems Model for Stroke Patients
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作者 Meifen Lv Jinyue Jiang +7 位作者 Luoqiong Lei Yuhua Gui Qiongfang Hu Fang Ye Lijuan Lu Hong Yang Na Yan Shiying Zhang 《Open Journal of Nursing》 2024年第7期329-343,共15页
Objective: To explore nutritional support under the Neuman systems model in treating dysphagia in stroke patients. Methods: In this retrospective study, we enrolled 97 patients with dysphagia after stroke admitted to ... Objective: To explore nutritional support under the Neuman systems model in treating dysphagia in stroke patients. Methods: In this retrospective study, we enrolled 97 patients with dysphagia after stroke admitted to our hospital, and randomly divided them into the Neuman group (n = 51) given nursing intervention based on Neuman systems model and a control group (n = 46) given routine nursing intervention. Both groups received nutritional support for 3 months. Nutritional indexes (serum total protein, plasma albumin, serum albumin, hemoglobin and transferrin levels) and immune indexes (immunoglobulin (Ig) A, IgG, IgM and total lymphocyte count (TLC) in both groups were recorded and compared. Pulmonary function recovery, video fluoroscopic swallowing study score, water swallowing test score, complication rate, and health knowledge mastery level were also compared between the two groups. Results: After the intervention, the Neuman group showed less decrease in the nutritional and immune index scores (serum total protein, plasma albumin, hemoglobin, serum albumin;IgA, IgG, IgM, and TLC;all P Conclusion: For patients with stroke and dysphagia, comprehensive nursing intervention (e.g., nutritional support) under theNeuman systems model can promote the recovery of immune, swallowing, and pulmonary function, reduce complication incidence and facilitate comprehensive rehabilitation, ensuring adequate nutritional intake. 展开更多
关键词 STROKE DYSPHAGIA Neuman Systems Model Nutritional support Pulmonary Function
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Literature Review on Support for Children and Families Experiencing Parental Bereavement
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作者 Rurie Namiki Keita Sasaki +1 位作者 Iku Taniguchi Rie Wakimizu 《Open Journal of Nursing》 2024年第4期139-163,共25页
Purpose: This study aimed to understand the actual nursing support in a wide perspective by reviewing overseas literature on support for children who have experienced parental bereavement and their families. The goal ... Purpose: This study aimed to understand the actual nursing support in a wide perspective by reviewing overseas literature on support for children who have experienced parental bereavement and their families. The goal was to identify future challenges in nursing support in clinical practice in Japan. Method: Literature searchable as of May 2023 was retrieved using PubMed, resulting in 11 relevant articles. Result: The results revealed the following: 1) For support provided to children, 13 codes were condensed into 5 subcategories and 4 categories. 2) For support provided to families, 36 codes were condensed into 11 subcategories and 4 categories. Conclusion: Open communication was found to be essential for supporting children and their families who have experienced parental bereavement. Moreover, involvement of multiple professions facilitated the provision of specialized support to address diverse needs of children and families, playing a crucial role in overcoming grief. Additionally, the effectiveness of support systems for bereaved families highlighted the need for nursing professionals in Japan to gain knowledge through learning opportunities and to establish a multi-disciplinary approach to support, thus indicating future challenges in nursing support. 展开更多
关键词 Terminal Care Family support CHILD Parental Death Palliative Care
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Meter-Scale Thin-Walled Structure with Lattice Infill for Fuel Tank Supporting Component of Satellite:Multiscale Design and Experimental Verification
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作者 Xiaoyu Zhang Huizhong Zeng +6 位作者 Shaohui Zhang Yan Zhang Mi Xiao Liping Liu Hao Zhou Hongyou Chai Liang Gao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期201-220,共20页
Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be f... Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be fabricated bymetallic additive manufacturing technique,such as selective laser melting(SLM).However,the maximum dimensions of actual structures are usually in a sub-meter scale,which results in restrictions on their appliance in aerospace and other fields.In this work,a meter-scale thin-walled structure with lattice infill is designed for the fuel tank supporting component of the satellite by integrating a self-supporting lattice into the thickness optimization of the thin-wall.The designed structure is fabricated by SLM of AlSi10Mg and cold metal transfer welding technique.Quasi-static mechanical tests and vibration tests are both conducted to verify the mechanical strength of the designed large-scale lattice thin-walled structure.The experimental results indicate that themeter-scale thin-walled structure with lattice infill could meet the dimension and lightweight requirements of most spacecrafts. 展开更多
关键词 Thin-walled structure lattice infill supporting component selective laser melting SATELLITE
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