The paper empirically studies the engineering practices of the national currency circulation information system-China Union Pay's Bankcard Information Exchange System.By integrating the meta-synthesis methodology ...The paper empirically studies the engineering practices of the national currency circulation information system-China Union Pay's Bankcard Information Exchange System.By integrating the meta-synthesis methodology and the financial information system engineering,the paper proposes basic principles and processes of the giant and complex financial information system engineering management,and further explores its paradigm and toolkit.展开更多
Objective:To examine what challenges and experiences a mother faces in caring for children with cerebral palsy(CP).As the main caregiver of children with CP,mothers are under multiple pressures.Even though mothers’ch...Objective:To examine what challenges and experiences a mother faces in caring for children with cerebral palsy(CP).As the main caregiver of children with CP,mothers are under multiple pressures.Even though mothers’challenges and experiences of children with CP will affect their quality of life and the rehabilitation of the children,little is known about their challenges and experiences during the whole care.Methods:A qualitative meta-synthesis was conducted to extract and analyze qualitative research from the PubMed,CINAHL,PsycINFO,Web of Science,Ovid and MEDLINE databases.Thirteen articles were selected and analyzed using thematic syntheses.Results:From 2522 screened abstracts,84 texts were reviewed,and 13 studies met the inclusion criteria.Mothers’challenges and experiences of children with CP include 4 themes,both positive and negative.Conclusions:The mothers of children with CP suffer from physical burden,as well as psychological pressure,in the care experience;social and healthcare support are their main challenges.Interventions to help them face the difficulties and adapt to the role of caregivers as soon as possible should target multiple aspects in order to maximize effectiveness,to promote the healthy growth of children with CP.展开更多
The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytica...The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical shells.By taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue equations.Besides,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are investigated.It is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.展开更多
This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydra...This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S paste.The results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age.展开更多
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi...Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems.展开更多
Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of coal.Consideration of the spatial heterogeneity of OB dump mate...Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of coal.Consideration of the spatial heterogeneity of OB dump materials is imperative for an adequate evaluation of the seismic stability of OB dump slopes.In this study,pseudo-static seismic stability analyses are carried out for an OB dump slope by considering the material parameters obtained from an insitu field investigation.Spatial heterogeneity is simulated through use of the random finite element method(RFEM)and the random limit equilibrium method(RLEM)and a comparative study is presented.Combinations of horizontal and vertical spatial correlation lengths were considered for simulating isotropic and anisotropic random fields within the OB dump slope.Seismic performances of the slope have been reported through the probability of failure and reliability index.It was observed that the RLEM approach overestimates failure probability(P_(f))by considering seismic stability with spatial heterogeneity.The P_(f)was observed to increase with an increase in the coefficient of variation of friction angle of the dump materials.Further,it was inferred that the RLEM approach may not be adequately applicable for assessing the seismic stability of an OB dump slope for a horizontal seismic coefficient that is more than or equal to 0.1.展开更多
The active equalization of lithium-ion batteries involves transferring energy from high-voltage cells to low-voltage cells,ensuring consistent voltage levels across the battery pack and maintaining safety.This paper p...The active equalization of lithium-ion batteries involves transferring energy from high-voltage cells to low-voltage cells,ensuring consistent voltage levels across the battery pack and maintaining safety.This paper presents a voltage balancing circuit and control method.First,a single capacitor method is used to design the circuit topology for energy transfer.Next,real-time voltage detection and control are employed to balance energy between cells.Finally,simulation and experimental results demonstrate the effectiveness of the proposed method,achieving balanced voltages of 3.97 V from initial voltages of 4.10,3.97,and 3.90 V.The proposed circuit is simple,reliable,and effectively prevents overcharge and overdischarge.展开更多
Since the plasticity of soil and the irregular shape of the excavation,the efficiency and stability of the traditional local radial basis function(RBF)collocation method(LRBFCM)are inadequate for analyzing three-dimen...Since the plasticity of soil and the irregular shape of the excavation,the efficiency and stability of the traditional local radial basis function(RBF)collocation method(LRBFCM)are inadequate for analyzing three-dimensional(3D)deformation of deep excavation.In this work,the technique known as the direct method,where the local influence nodes are collocated on a straight line,is introduced to optimize the LRBFCM.The direct method can improve the accuracy of the partial derivative,reduce the size effect caused by the large length-width ratio,and weaken the influence of the shape parameters on the LRBFCM.The mapping technique is adopted to transform the physical coordinates of a quadratic-type block to normalized coordinates,in which the deformation problem can easily be solved using the direct method.The stability of the LRBFCM is further modified by considering the irregular shape of 3D excavation,which is divided into several quadratic-type blocks.The soil’s plasticity is described by the Drucker-Prager(D-P)model.The improved LRBFCM is integrated with the incremental method to analyze the plasticity.Five different examples,including strip excavations and circular excavations,are presented to validate the proposed approach’s efficiency.展开更多
The investigation of leachate-contaminated clay(LCC)is essential for landfill engineering assessment and achievement of sustainable development goals.Several static and dynamic laboratory tests,including unconfined co...The investigation of leachate-contaminated clay(LCC)is essential for landfill engineering assessment and achievement of sustainable development goals.Several static and dynamic laboratory tests,including unconfined compressive strength(UCS),California bearing ratio(CBR),and cyclic simple shear,are conducted.Cyclic simple shear experiments on LCCs were performed to evaluate the damping and shear modulus.The investigated factors are vertical load(VL),leachate content(LC),frequency(F),and shear strain(ShS)for LCC.Forensic-based investigation optimization(FBIO)and equilibrium optimizer algorithm(EOA)were utilized in addition to multiple types of ensemble models,including adaptive boosting(ADB),gradient boosting regression tree(GBRT),extreme gradient boosting(XGB) and random forest(RF).The comparison of the methods showed that GBRT-FBIO and XGB-EOA models outperformed other models for shear modulus and damping of LCC.The p-value less than 0.0001 shows the significance of the used models in the response surface methodology(RSM)method.展开更多
BACKGROUND Inflammatory bowel disease(IBD)is a common chronic intestinal inflammatory disease.High oxidative stress is a treatment target for IBD.Cerium oxide(CeO2)nanomaterials as nanozymes with antioxidant activity ...BACKGROUND Inflammatory bowel disease(IBD)is a common chronic intestinal inflammatory disease.High oxidative stress is a treatment target for IBD.Cerium oxide(CeO2)nanomaterials as nanozymes with antioxidant activity are potential drugs for the treatment of colitis.AIM To synthesize hollow cerium(H-CeO2)nanoparticles by one-step method and to validate the therapeutic efficacy of H-CeO2 in IBD.METHODS H-CeO2 was synthesized by one-step method and examined its characterization and nanoenzymatic activity.Subsequently,we constructed dextran sulfate so-dium(DSS)-induced colitis in mice to observe the effects of H-CeO2 on colonic inflammation.The effects of H-CeO2 on colon inflammation and reactive oxygen species(ROS)levels in IBD mice were detected by hematoxylin and eosin staining and dichlorofluorescein diacetate staining,respectively.Finally,the biological sa-fety of H-CeO2 on mice was evaluated by hematoxylin and eosin staining,blood routine,and blood biochemistry.RESULTS H-CeO2 nanoparticles prepared by the one-step method were uniform,monodi-sperse and hollow.H-CeO2 had a good ability to scavenge ROS,∙OH and∙OOH.H-CeO2 reduced DSS-induced decreases in body weight and colon length,colonic epithelial damage,inflammatory infiltration,and ROS accumulation.H-CeO2 administration reduced the disease activity index of DSS-induced animals from about 8 to 5.H-CeO2 had no significant effect on body weight,total platelet count,hemoglobin,white blood cell,and red blood cell counts in healthy mice.No significant damage to major organs was observed in healthy mice following H-CeO2 administration.CONCLUSION The one-step synthesis of H-CeO2 nanomaterials had good antioxidant activity,biosafety,and inhibited deve-lopment of DSS-induced IBD in mice by scavenging ROS.展开更多
BACKGROUND Gastric ulcer perforation is a critical condition that can lead to significant morbidity and mortality if not promptly addressed.It is often the result of chronic peptic ulcer disease,which is characterized...BACKGROUND Gastric ulcer perforation is a critical condition that can lead to significant morbidity and mortality if not promptly addressed.It is often the result of chronic peptic ulcer disease,which is characterized by a breach in the gastric wall due to ulceration.Surgical intervention is essential for managing this life-threatening complication.However,the optimal surgical technique remains debatable among clinicians.Various methods have been employed,including simple closure,omental patch repair,and partial gastrectomy,each with distinct advantages and disadvantages.Understanding the comparative efficacy and postoperative outcomes of these techniques is crucial for improving patient care and surgical decision-making.This study addresses the need for a comprehensive analysis in this area.AIM To compare the efficacy and postoperative complications of different surgical methods for the treatment of gastric ulcer perforation.METHODS A retrospective analysis was conducted on 120 patients who underwent surgery for gastric ulcer perforation between September 2020 and June 2023.The patients were divided into three groups based on the surgical method:Simple closure,omental patch repair,and partial gastrectomy.The primary outcomes were the operative success rate and incidence of postoperative complications.Secondary outcomes included the length of hospital stay,recovery time,and long-term quality of life.RESULTS The operative success rates for simple closure,omental patch repair,and partial gastrectomy were 92.5%,95%,and 97.5%,respectively.Postoperative complications occurred in 20%,15%,and 17.5%of patients in each group,respectively.The partial gastrectomy group showed a significantly longer operative time(P<0.001)but the lowest rate of ulcer recurrence(2.5%,P<0.05).The omental patch repair group demonstrated the shortest hospital stay(mean 7.2 days,P<0.05)and fastest recovery time.CONCLUSION While all three surgical methods showed high success rates,omental patch repair demonstrated the best overall outcomes,with a balance of high efficacy,low complication rates,and shorter recovery time.However,the choice of the surgical method should be tailored to individual patient factors and the surgeon’s expertise.展开更多
This paper presents a framework for constructing surrogate models for sensitivity analysis of structural dynamics behavior.Physical models involving deformation,such as collisions,vibrations,and penetration,are devel-...This paper presents a framework for constructing surrogate models for sensitivity analysis of structural dynamics behavior.Physical models involving deformation,such as collisions,vibrations,and penetration,are devel-oped using the material point method.To reduce the computational cost of Monte Carlo simulations,response surface models are created as surrogate models for the material point system to approximate its dynamic behavior.An adaptive randomized greedy algorithm is employed to construct a sparse polynomial chaos expansion model with a fixed order,effectively balancing the accuracy and computational efficiency of the surrogate model.Based on the sparse polynomial chaos expansion,sensitivity analysis is conducted using the global finite difference and Sobol methods.Several examples of structural dynamics are provided to demonstrate the effectiveness of the proposed method in addressing structural dynamics problems.展开更多
Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly ...Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses.展开更多
Objective:To examine the differences in effectiveness and side effects between pyrimethamine-based and non-pyrimethamine-based regimens for toxoplasma encephalitis since the availability of pyrimethamine in Indonesia ...Objective:To examine the differences in effectiveness and side effects between pyrimethamine-based and non-pyrimethamine-based regimens for toxoplasma encephalitis since the availability of pyrimethamine in Indonesia is currently limited due to its withdrawal from the market.Methods:A systematic review and meta-synthesis study that was carried out by following a protocol guided by the Preffered Reporting Items for Systematic Review and Meta-analysis(PRISMA).Effectiveness measures included clinical improvement,mortality,and radiological improvement.We evaluated selected articles narratively because of the limitations of homogeneity.The risk of bias in RCTs was assessed using the Cochrane Risk of Bias tool for RCT(ROB 2.0)and cohort studies were assessed using the Risk of Bias In Non-Randomized Studies of Interventions(ROBINS-1)tool.Research quality was assessed using the GradePro software.Results:We included two retrospective cohort studies and one RCT.Narrative outcome assessment in these three studies did not show significant difference in effectiveness between pyrimethamine-based and non-pyrimethamine-based regimens for toxoplasma encephalitis treatment.However,drug side effects were consistently higher in the pyrimethamine-based regimen.Conclusions:This study has a high risk of bias.The quality of the research also has a low recommendation value.However,the results may be considered for application if a standard regimen is not available.展开更多
Objectives define the boundaries of complex engineering system.It is a hard work to identify the specific objectives of a complex engineering system.The objectives system development needs a complicated process,from n...Objectives define the boundaries of complex engineering system.It is a hard work to identify the specific objectives of a complex engineering system.The objectives system development needs a complicated process,from nix to prototype,and to final definition.The total process will cover the following course:from chaos to well-ordered;from qualitativeness to combination of quantitativeness and qualitativenss,then from qualitativeness to quantitativeness(a recurrent process),expert experience and theoretical science,rationality and sensibility,synthesis analysis and meta-synthesis,routinization and non-routinization.Such process is explicit in phase development yet overlapped;mutually confined yet mutually independent;permeated conflicts yet pregnant in harmony.This article explores the complexity of Sutong Bridge's objectives development and the process of meta-synthesis in the Sutong Bridge engineering.展开更多
Objective: Nurses play important roles in caring for dying patients and their families. Difficulties students confronted when facing dying patients challenge the quality of nursing education. A better understanding of...Objective: Nurses play important roles in caring for dying patients and their families. Difficulties students confronted when facing dying patients challenge the quality of nursing education. A better understanding of students' experiences would enhance teachers' ability in helping students. This study aims to describe available evidence about nursing students' experiences when caring for dying patients and their families.Methods: A review of qualitative studies published between 2005 and 2017 was undertaken using the following databases: MEDLINE, CINAHL, ProQuest Central, ScienceDirect, and CNKI. The keywords included were nursing students, experience, care, end-of-life, and dying. Qualitative Assessment and Review Instrument was used to assess the quality of the studies by two independent reviewers. The data from the studies were analyzed by meta-synthesis.Results: Eighteen English and two Chinese studies were selected in this review. Four themes were emerged:(1) Students with dying patients: students did not have enough ability in symptoms control, comfort supply, and therapeutic communication for dying patients.(2) Students with the patients' families: students advocated more caring for patients' families.(3) Students with the surroundings: professional medical staffs, especially the nursing preceptors, were key roles in constructing a supporting system for students.(4) Students with themselves: nursing students underwent various negative feelings and adopted both negative and positive strategies to cope with such feelings;students experienced professional and personal development during the caring for dying patients.Conclusions: Nursing students' abilities in terminal symptom control, comfort supply, and therapeutic communication should be improved by more theoretic learning and simulation practice. The nursing preceptors were key roles in constructing a supporting system for students and helping them to control the negative emotions when facing dying patients.展开更多
The purpose of this review is to integrate the psychological experience of infected individuals during the pandemic.The spread of the pandemic has led to psychological and emotional impacts on patients.A qualitative s...The purpose of this review is to integrate the psychological experience of infected individuals during the pandemic.The spread of the pandemic has led to psychological and emotional impacts on patients.A qualitative synthesis is needed to identify,appraise,and integrate the available qualitative findings to provide an evidence for the development of interventions.A meta-aggregation approach was used to analyze studies published in English from January 2020 to August 2021.The JBI Qualitative Assessment and Review Instrument was used to assess the methodological quality of included studies.The ConQual system was used to establish the dependability and credibility in the synthesized findings.Six phenomenological studies and one narrative inquiry with an overall quality score of 70%-100% were included.The research findings from 87 participants in eligible studies were aggregated into three categories based on similarity of meaning.Two synthesized findings were generated and rated as moderate based on the ConQual score.The synthesized findings suggested that participants had psychological distress such as fear,anxiety,loneliness,and uncertainty,but they accepted the fact of being infected and tried to adjust themselves using some self-coping strategies,such as diverting attention from disease,seeking help from professional counselors,relying on religious beliefs,and participating in religious activities.They would like to learn more about infections and diseases and needed more informational support from health-care professionals.They were looking forward to recovery from the disease.展开更多
The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(R...The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(RCZ) is built. The formula for an ultimate cutting force is established based on the limit equilibrium principle. The relationship between digital drilling parameters(DDP) and the c-φ parameter(DDP-cφ formula, where c refers to the cohesion and φ refers to the internal friction angle) is derived, and the response of drilling parameters and cutting ratio to the strength parameters is analyzed. The drillingbased measuring method for the c-φ parameter of rock is constructed. The laboratory verification test is then completed, and the difference in results between the drilling test and the compression test is less than 6%. On this basis, in-situ rock drilling tests in a traffic tunnel and a coal mine roadway are carried out, and the strength parameters of the surrounding rock are effectively tested. The average difference ratio of the results is less than 11%, which verifies the effectiveness of the proposed method for obtaining the strength parameters based on digital drilling. This study provides methodological support for field testing of rock strength parameters.展开更多
In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic...In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods.展开更多
This meta-synthesis presents the results of qualitative studies on puerperal perception concerning woman’s care in the post-partum period. Four databases were researched using keywords such as “postnatal care” (or)...This meta-synthesis presents the results of qualitative studies on puerperal perception concerning woman’s care in the post-partum period. Four databases were researched using keywords such as “postnatal care” (or) “postpartum period”, (and) “care”, “women”, “perception”, “qualitative research”, “women’s health services”, “community health services”, “allied health personnel”, “primary health care”, resulting in 9 articles for analysis. Six themes were identified: interpersonal relationship, information, communication, attending the necessities, service organization and other supports. Results report mainly on the unsatisfactory professional care for women, appreciating the form of dealing with promptness and the timing to be attended;trust;content, coherence and the way to inform;clarification of doubts;friendly conversation and clinical assistance. The professional workload was restricted on postpartum period care quality. There were gaps found in clinical practice and in dialogical communication and information on women’s health necessities.展开更多
文摘The paper empirically studies the engineering practices of the national currency circulation information system-China Union Pay's Bankcard Information Exchange System.By integrating the meta-synthesis methodology and the financial information system engineering,the paper proposes basic principles and processes of the giant and complex financial information system engineering management,and further explores its paradigm and toolkit.
文摘Objective:To examine what challenges and experiences a mother faces in caring for children with cerebral palsy(CP).As the main caregiver of children with CP,mothers are under multiple pressures.Even though mothers’challenges and experiences of children with CP will affect their quality of life and the rehabilitation of the children,little is known about their challenges and experiences during the whole care.Methods:A qualitative meta-synthesis was conducted to extract and analyze qualitative research from the PubMed,CINAHL,PsycINFO,Web of Science,Ovid and MEDLINE databases.Thirteen articles were selected and analyzed using thematic syntheses.Results:From 2522 screened abstracts,84 texts were reviewed,and 13 studies met the inclusion criteria.Mothers’challenges and experiences of children with CP include 4 themes,both positive and negative.Conclusions:The mothers of children with CP suffer from physical burden,as well as psychological pressure,in the care experience;social and healthcare support are their main challenges.Interventions to help them face the difficulties and adapt to the role of caregivers as soon as possible should target multiple aspects in order to maximize effectiveness,to promote the healthy growth of children with CP.
基金supported by the National Natural Science Foundation of China(12172023).
文摘The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical shells.By taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue equations.Besides,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are investigated.It is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.
基金Funded by the Natural Science Foundation of Jiangsu Province(No.BK20241529)China Postdoctoral Science Foundation(No.2024M750736)。
文摘This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S paste.The results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age.
基金supported by the Innovation Foundation of Provincial Education Department of Gansu(2024B-005)the Gansu Province National Science Foundation(22YF7GA182)the Fundamental Research Funds for the Central Universities(No.lzujbky2022-kb01)。
文摘Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems.
基金the financial support provided by MHRD,Govt.of IndiaCoal India Limited for providing financial assistance for the research(Project No.CIL/R&D/01/73/2021)the partial financial support provided by the Ministry of Education,Government of India,under SPARC project(Project No.P1207)。
文摘Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of coal.Consideration of the spatial heterogeneity of OB dump materials is imperative for an adequate evaluation of the seismic stability of OB dump slopes.In this study,pseudo-static seismic stability analyses are carried out for an OB dump slope by considering the material parameters obtained from an insitu field investigation.Spatial heterogeneity is simulated through use of the random finite element method(RFEM)and the random limit equilibrium method(RLEM)and a comparative study is presented.Combinations of horizontal and vertical spatial correlation lengths were considered for simulating isotropic and anisotropic random fields within the OB dump slope.Seismic performances of the slope have been reported through the probability of failure and reliability index.It was observed that the RLEM approach overestimates failure probability(P_(f))by considering seismic stability with spatial heterogeneity.The P_(f)was observed to increase with an increase in the coefficient of variation of friction angle of the dump materials.Further,it was inferred that the RLEM approach may not be adequately applicable for assessing the seismic stability of an OB dump slope for a horizontal seismic coefficient that is more than or equal to 0.1.
基金funded by the Basic Science(Natural Science)Research Project of Colleges and Universities in Jiangsu Province,Grant Number 22KJD470002.
文摘The active equalization of lithium-ion batteries involves transferring energy from high-voltage cells to low-voltage cells,ensuring consistent voltage levels across the battery pack and maintaining safety.This paper presents a voltage balancing circuit and control method.First,a single capacitor method is used to design the circuit topology for energy transfer.Next,real-time voltage detection and control are employed to balance energy between cells.Finally,simulation and experimental results demonstrate the effectiveness of the proposed method,achieving balanced voltages of 3.97 V from initial voltages of 4.10,3.97,and 3.90 V.The proposed circuit is simple,reliable,and effectively prevents overcharge and overdischarge.
基金supported by grants from the National Natural Science Foundation of China(Nos.12172159 and 12362019).
文摘Since the plasticity of soil and the irregular shape of the excavation,the efficiency and stability of the traditional local radial basis function(RBF)collocation method(LRBFCM)are inadequate for analyzing three-dimensional(3D)deformation of deep excavation.In this work,the technique known as the direct method,where the local influence nodes are collocated on a straight line,is introduced to optimize the LRBFCM.The direct method can improve the accuracy of the partial derivative,reduce the size effect caused by the large length-width ratio,and weaken the influence of the shape parameters on the LRBFCM.The mapping technique is adopted to transform the physical coordinates of a quadratic-type block to normalized coordinates,in which the deformation problem can easily be solved using the direct method.The stability of the LRBFCM is further modified by considering the irregular shape of 3D excavation,which is divided into several quadratic-type blocks.The soil’s plasticity is described by the Drucker-Prager(D-P)model.The improved LRBFCM is integrated with the incremental method to analyze the plasticity.Five different examples,including strip excavations and circular excavations,are presented to validate the proposed approach’s efficiency.
文摘The investigation of leachate-contaminated clay(LCC)is essential for landfill engineering assessment and achievement of sustainable development goals.Several static and dynamic laboratory tests,including unconfined compressive strength(UCS),California bearing ratio(CBR),and cyclic simple shear,are conducted.Cyclic simple shear experiments on LCCs were performed to evaluate the damping and shear modulus.The investigated factors are vertical load(VL),leachate content(LC),frequency(F),and shear strain(ShS)for LCC.Forensic-based investigation optimization(FBIO)and equilibrium optimizer algorithm(EOA)were utilized in addition to multiple types of ensemble models,including adaptive boosting(ADB),gradient boosting regression tree(GBRT),extreme gradient boosting(XGB) and random forest(RF).The comparison of the methods showed that GBRT-FBIO and XGB-EOA models outperformed other models for shear modulus and damping of LCC.The p-value less than 0.0001 shows the significance of the used models in the response surface methodology(RSM)method.
文摘BACKGROUND Inflammatory bowel disease(IBD)is a common chronic intestinal inflammatory disease.High oxidative stress is a treatment target for IBD.Cerium oxide(CeO2)nanomaterials as nanozymes with antioxidant activity are potential drugs for the treatment of colitis.AIM To synthesize hollow cerium(H-CeO2)nanoparticles by one-step method and to validate the therapeutic efficacy of H-CeO2 in IBD.METHODS H-CeO2 was synthesized by one-step method and examined its characterization and nanoenzymatic activity.Subsequently,we constructed dextran sulfate so-dium(DSS)-induced colitis in mice to observe the effects of H-CeO2 on colonic inflammation.The effects of H-CeO2 on colon inflammation and reactive oxygen species(ROS)levels in IBD mice were detected by hematoxylin and eosin staining and dichlorofluorescein diacetate staining,respectively.Finally,the biological sa-fety of H-CeO2 on mice was evaluated by hematoxylin and eosin staining,blood routine,and blood biochemistry.RESULTS H-CeO2 nanoparticles prepared by the one-step method were uniform,monodi-sperse and hollow.H-CeO2 had a good ability to scavenge ROS,∙OH and∙OOH.H-CeO2 reduced DSS-induced decreases in body weight and colon length,colonic epithelial damage,inflammatory infiltration,and ROS accumulation.H-CeO2 administration reduced the disease activity index of DSS-induced animals from about 8 to 5.H-CeO2 had no significant effect on body weight,total platelet count,hemoglobin,white blood cell,and red blood cell counts in healthy mice.No significant damage to major organs was observed in healthy mice following H-CeO2 administration.CONCLUSION The one-step synthesis of H-CeO2 nanomaterials had good antioxidant activity,biosafety,and inhibited deve-lopment of DSS-induced IBD in mice by scavenging ROS.
文摘BACKGROUND Gastric ulcer perforation is a critical condition that can lead to significant morbidity and mortality if not promptly addressed.It is often the result of chronic peptic ulcer disease,which is characterized by a breach in the gastric wall due to ulceration.Surgical intervention is essential for managing this life-threatening complication.However,the optimal surgical technique remains debatable among clinicians.Various methods have been employed,including simple closure,omental patch repair,and partial gastrectomy,each with distinct advantages and disadvantages.Understanding the comparative efficacy and postoperative outcomes of these techniques is crucial for improving patient care and surgical decision-making.This study addresses the need for a comprehensive analysis in this area.AIM To compare the efficacy and postoperative complications of different surgical methods for the treatment of gastric ulcer perforation.METHODS A retrospective analysis was conducted on 120 patients who underwent surgery for gastric ulcer perforation between September 2020 and June 2023.The patients were divided into three groups based on the surgical method:Simple closure,omental patch repair,and partial gastrectomy.The primary outcomes were the operative success rate and incidence of postoperative complications.Secondary outcomes included the length of hospital stay,recovery time,and long-term quality of life.RESULTS The operative success rates for simple closure,omental patch repair,and partial gastrectomy were 92.5%,95%,and 97.5%,respectively.Postoperative complications occurred in 20%,15%,and 17.5%of patients in each group,respectively.The partial gastrectomy group showed a significantly longer operative time(P<0.001)but the lowest rate of ulcer recurrence(2.5%,P<0.05).The omental patch repair group demonstrated the shortest hospital stay(mean 7.2 days,P<0.05)and fastest recovery time.CONCLUSION While all three surgical methods showed high success rates,omental patch repair demonstrated the best overall outcomes,with a balance of high efficacy,low complication rates,and shorter recovery time.However,the choice of the surgical method should be tailored to individual patient factors and the surgeon’s expertise.
基金support from the National Natural Science Foundation of China(Grant Nos.52174123&52274222).
文摘This paper presents a framework for constructing surrogate models for sensitivity analysis of structural dynamics behavior.Physical models involving deformation,such as collisions,vibrations,and penetration,are devel-oped using the material point method.To reduce the computational cost of Monte Carlo simulations,response surface models are created as surrogate models for the material point system to approximate its dynamic behavior.An adaptive randomized greedy algorithm is employed to construct a sparse polynomial chaos expansion model with a fixed order,effectively balancing the accuracy and computational efficiency of the surrogate model.Based on the sparse polynomial chaos expansion,sensitivity analysis is conducted using the global finite difference and Sobol methods.Several examples of structural dynamics are provided to demonstrate the effectiveness of the proposed method in addressing structural dynamics problems.
文摘Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses.
文摘Objective:To examine the differences in effectiveness and side effects between pyrimethamine-based and non-pyrimethamine-based regimens for toxoplasma encephalitis since the availability of pyrimethamine in Indonesia is currently limited due to its withdrawal from the market.Methods:A systematic review and meta-synthesis study that was carried out by following a protocol guided by the Preffered Reporting Items for Systematic Review and Meta-analysis(PRISMA).Effectiveness measures included clinical improvement,mortality,and radiological improvement.We evaluated selected articles narratively because of the limitations of homogeneity.The risk of bias in RCTs was assessed using the Cochrane Risk of Bias tool for RCT(ROB 2.0)and cohort studies were assessed using the Risk of Bias In Non-Randomized Studies of Interventions(ROBINS-1)tool.Research quality was assessed using the GradePro software.Results:We included two retrospective cohort studies and one RCT.Narrative outcome assessment in these three studies did not show significant difference in effectiveness between pyrimethamine-based and non-pyrimethamine-based regimens for toxoplasma encephalitis treatment.However,drug side effects were consistently higher in the pyrimethamine-based regimen.Conclusions:This study has a high risk of bias.The quality of the research also has a low recommendation value.However,the results may be considered for application if a standard regimen is not available.
基金National Scientific and Technology Supporting Program of 11th 5-Year Plan(No.2006BAG04B06)
文摘Objectives define the boundaries of complex engineering system.It is a hard work to identify the specific objectives of a complex engineering system.The objectives system development needs a complicated process,from nix to prototype,and to final definition.The total process will cover the following course:from chaos to well-ordered;from qualitativeness to combination of quantitativeness and qualitativenss,then from qualitativeness to quantitativeness(a recurrent process),expert experience and theoretical science,rationality and sensibility,synthesis analysis and meta-synthesis,routinization and non-routinization.Such process is explicit in phase development yet overlapped;mutually confined yet mutually independent;permeated conflicts yet pregnant in harmony.This article explores the complexity of Sutong Bridge's objectives development and the process of meta-synthesis in the Sutong Bridge engineering.
基金supported by the Macao Science and Technology Development Fund(No.FDCT 276/2017/P)
文摘Objective: Nurses play important roles in caring for dying patients and their families. Difficulties students confronted when facing dying patients challenge the quality of nursing education. A better understanding of students' experiences would enhance teachers' ability in helping students. This study aims to describe available evidence about nursing students' experiences when caring for dying patients and their families.Methods: A review of qualitative studies published between 2005 and 2017 was undertaken using the following databases: MEDLINE, CINAHL, ProQuest Central, ScienceDirect, and CNKI. The keywords included were nursing students, experience, care, end-of-life, and dying. Qualitative Assessment and Review Instrument was used to assess the quality of the studies by two independent reviewers. The data from the studies were analyzed by meta-synthesis.Results: Eighteen English and two Chinese studies were selected in this review. Four themes were emerged:(1) Students with dying patients: students did not have enough ability in symptoms control, comfort supply, and therapeutic communication for dying patients.(2) Students with the patients' families: students advocated more caring for patients' families.(3) Students with the surroundings: professional medical staffs, especially the nursing preceptors, were key roles in constructing a supporting system for students.(4) Students with themselves: nursing students underwent various negative feelings and adopted both negative and positive strategies to cope with such feelings;students experienced professional and personal development during the caring for dying patients.Conclusions: Nursing students' abilities in terminal symptom control, comfort supply, and therapeutic communication should be improved by more theoretic learning and simulation practice. The nursing preceptors were key roles in constructing a supporting system for students and helping them to control the negative emotions when facing dying patients.
基金The authors would like to thank research funding from the Macao Polytechnic University(Code:RP/ESCSD-02/2021).
文摘The purpose of this review is to integrate the psychological experience of infected individuals during the pandemic.The spread of the pandemic has led to psychological and emotional impacts on patients.A qualitative synthesis is needed to identify,appraise,and integrate the available qualitative findings to provide an evidence for the development of interventions.A meta-aggregation approach was used to analyze studies published in English from January 2020 to August 2021.The JBI Qualitative Assessment and Review Instrument was used to assess the methodological quality of included studies.The ConQual system was used to establish the dependability and credibility in the synthesized findings.Six phenomenological studies and one narrative inquiry with an overall quality score of 70%-100% were included.The research findings from 87 participants in eligible studies were aggregated into three categories based on similarity of meaning.Two synthesized findings were generated and rated as moderate based on the ConQual score.The synthesized findings suggested that participants had psychological distress such as fear,anxiety,loneliness,and uncertainty,but they accepted the fact of being infected and tried to adjust themselves using some self-coping strategies,such as diverting attention from disease,seeking help from professional counselors,relying on religious beliefs,and participating in religious activities.They would like to learn more about infections and diseases and needed more informational support from health-care professionals.They were looking forward to recovery from the disease.
基金supported by the National Key Research and Development Program of China(No.2023YFC2907600)the National Natural Science Foundation of China(Nos.42077267,42277174 and 52074164)+2 种基金the Natural Science Foundation of Shandong Province,China(No.ZR2020JQ23)the Opening Project of State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology(No.KFJJ21-02Z)the Fundamental Research Funds for the Central Universities,China(No.2022JCCXSB03).
文摘The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(RCZ) is built. The formula for an ultimate cutting force is established based on the limit equilibrium principle. The relationship between digital drilling parameters(DDP) and the c-φ parameter(DDP-cφ formula, where c refers to the cohesion and φ refers to the internal friction angle) is derived, and the response of drilling parameters and cutting ratio to the strength parameters is analyzed. The drillingbased measuring method for the c-φ parameter of rock is constructed. The laboratory verification test is then completed, and the difference in results between the drilling test and the compression test is less than 6%. On this basis, in-situ rock drilling tests in a traffic tunnel and a coal mine roadway are carried out, and the strength parameters of the surrounding rock are effectively tested. The average difference ratio of the results is less than 11%, which verifies the effectiveness of the proposed method for obtaining the strength parameters based on digital drilling. This study provides methodological support for field testing of rock strength parameters.
基金The Guangdong Basic and Applied Basic Research Foundation(2022A1515010730)National Natural Science Foundation of China(32001647)+2 种基金National Natural Science Foundation of China(31972022)Financial and moral assistance supported by the Guangdong Basic and Applied Basic Research Foundation(2019A1515011996)111 Project(B17018)。
文摘In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods.
文摘This meta-synthesis presents the results of qualitative studies on puerperal perception concerning woman’s care in the post-partum period. Four databases were researched using keywords such as “postnatal care” (or) “postpartum period”, (and) “care”, “women”, “perception”, “qualitative research”, “women’s health services”, “community health services”, “allied health personnel”, “primary health care”, resulting in 9 articles for analysis. Six themes were identified: interpersonal relationship, information, communication, attending the necessities, service organization and other supports. Results report mainly on the unsatisfactory professional care for women, appreciating the form of dealing with promptness and the timing to be attended;trust;content, coherence and the way to inform;clarification of doubts;friendly conversation and clinical assistance. The professional workload was restricted on postpartum period care quality. There were gaps found in clinical practice and in dialogical communication and information on women’s health necessities.