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Clinical competency:perceptions of nursing interns and clinical mentors
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作者 Jackline Prathibha Radhika R.Pai Linu Sara George 《Frontiers of Nursing》 2024年第1期105-110,共6页
Objective:To assess the clinical competency of nursing interns and the perception of clinical nurse mentors toward student nurses'clinical competency.Methods:A study was carried out among 104 nursing interns and 2... Objective:To assess the clinical competency of nursing interns and the perception of clinical nurse mentors toward student nurses'clinical competency.Methods:A study was carried out among 104 nursing interns and 26 clinical nurse mentors using the purposive sampling technique.A self-repor ted perception scale was used to collect the data.Results:In general,most nursing interns perceived themselves as clinically competent during the internship.The clinical nurse mentors too repor ted that the current internship is helping the nursing interns in becoming competent.Conclusions:Frequent clinical evaluation,buddy system,provision of stipends,good leadership,and coordination between the academic institute and hospital are repor ted as the critical motivating factors for improving the clinical competency of student interns. 展开更多
关键词 clinical competency clinical nurse mentors COMPETENCE internsHIP nursing interns PERCEPTION
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Research and Application of Bedside Rhetorical Teaching Method in Teaching Nursing Interns
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作者 Rui Cao 《Journal of Contemporary Educational Research》 2024年第4期226-229,共4页
Objective:To observe and analyze the application of the bedside rhetorical teaching method in teaching nursing interns.Methods:A total of 64 nursing interns in the gastroenterology department of our hospital from July... Objective:To observe and analyze the application of the bedside rhetorical teaching method in teaching nursing interns.Methods:A total of 64 nursing interns in the gastroenterology department of our hospital from July 2022 to May 2023 were randomly divided into two groups,32 cases in the control group and 32 cases in the intervention group.The control group was given conventional teaching methods,and the intervention group was given the bedside rhetorical teaching method on the basis of the conventional teaching.The differences in the methods of teaching between the two groups were compared after the end of the internship,and there was a statistically significant difference with P<0.05.Results:The scores of the interns in the intervention group were significantly better than those of the control group in theoretical knowledge,communication skills,and case analysis items(P<0.05).Conclusion:The bedside rhetorical teaching method transforms classroom education into bedside teaching,which enables the interns to apply the theoretical knowledge to clinical practice,and has a higher improvement in the three aspects of disease knowledge,communication skills,and case analysis,cultivates the interns’comprehensive clinical skills,and lays a good foundation for the future entry into the nursing field. 展开更多
关键词 Bedside rhetorical teaching method Nursing interns teaching Application research
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Application of the “Six-Step Teaching Method” in the Nursing Teaching of Obstetric Interns
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作者 Rui Liu Kun Yuan Yuanyuan Li 《Open Journal of Nursing》 2023年第9期615-623,共9页
Objective: The “six-step teaching method” is a teaching method, which is summarized based on practical experience. This study aimed to explore the effect of “six-step teaching method” in clinical teaching of ... Objective: The “six-step teaching method” is a teaching method, which is summarized based on practical experience. This study aimed to explore the effect of “six-step teaching method” in clinical teaching of obstetrics. Methods: A quasi-experimental study design was used, 30 nursing students who entered obstetrics practice from March 2022 to July 2022 were selected as the control group according to the order of time, and traditional teaching methods were adopted. From August to December 2022, 30 interns were selected as the experimental group, and the “six-step teaching method” was adopted. After 8 weeks of clinical practice, the assessment results and teaching effect satisfaction of the two groups were compared. Results: The scores of obstetrical specialty in the experimental group were higher than those in the control group, and the difference was statistically significant (P < 0.05);The evaluation of teaching methods, teaching quality, classroom atmosphere and individual observation ability, clinical thinking ability and nurse-patient communication ability of the experimental group were higher than those of the control group, and the differences were statistically significant (P Conclusion: “six-step teaching method” can effectively master the professional knowledge of obstetrics, stimulate the clinical thinking ability of interns, and improve the teaching effect and satisfaction. . 展开更多
关键词 “Six-Step Teaching Method” Obstetrics Intern Nursing Education
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Study on the Effectiveness of the Application of Perineal Wound Model in Teaching Midwife Interns
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作者 Chunrong Yang Lili Zhang +1 位作者 Duomei Ren Meirong Tian 《Journal of Clinical and Nursing Research》 2023年第3期24-27,共4页
Objective:To discuss and analyze the effectiveness of the application of perineal wound model in teaching midwife interns.Methods:The research subjects in this study were 40 midwife interns who enrolled in our hospita... Objective:To discuss and analyze the effectiveness of the application of perineal wound model in teaching midwife interns.Methods:The research subjects in this study were 40 midwife interns who enrolled in our hospital from January 2020 to December 2022,which were divided into a control group(consisted of 20 interns,taught with the conventional method)and a research group(consisted of 20 participants,taught with the perineal wound model)using the random number table method.The outcomes of these two groups were compared.Results:The examination results of the research group were better than control group(P<0.05);the interns of the research group were more satisfied towards the teaching method compared to the control group(P<0.05).Conclusion:Applying the perineal wound model in teaching midwife interns could effectively improve their examination achievements and teaching satisfaction,which brings a significant clinical value. 展开更多
关键词 Midwife intern Perineum wound Examination results Teaching satisfaction
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Professional identity, wellness, and future hope among nurse interns in Egypt 被引量:1
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作者 Rasha Mohammed Hussien Mahmoud Abdul Hameed Shahin Mervat Elshahat Ibrahim 《Frontiers of Nursing》 2021年第3期279-290,共12页
Objective:Since nursing is a performance-based profession,clinical learning environments play an important role in the acquisition of professional abilities and train nursing students to enter the nursing profession a... Objective:Since nursing is a performance-based profession,clinical learning environments play an important role in the acquisition of professional abilities and train nursing students to enter the nursing profession and become a registered nurse.The study aimed to investigate the relations among professional identity,wellness,and future hope in nurse interns.Methods:A cross-sectional,analytic,descriptive,correlational study design was used to test these relations in the study where 210 nurse interns’students were selected using a convenience sampling from Zagazig University hospitals and Suez Canal University hospitals in Egypt.The questionnaires consisted of 4 parts,namely demographic characteristics,Professional Identity Scale for Nursing Students(PISNS),Holistic Health and Wellness Survey,and Hope scale.Results:Less than half of the study sample had chosen nursing specialty by own will(43.8%),while slightly more than half of them had a"very good"graduation level,and had no nursing role model.The lowest mean professional identity score was for independence in career choice while the highest was for social modeling.The repor ted physical wellness mean-score was the least,while social wellness was the highest.Professional identity,wellness,and future hope scores differed significantly based on nurse interns’personal characteristics.There were statistically significant,positive,weak-to-moderate correlations among the scores of professional identity,wellness,and future hope;however,the"choice of nursing study by own will"was a statistically significant independent positive predictor of the scores of professional identity,wellness,and future hope.Conclusions:Nurse interns’professional identity,wellness,and future hope were positively inter-correlated.However,nurse interns’wellness was the lowest,and it should be fostered as it was the main predictor for future hope.The internship programs should be modulated to improve nurse interns’professional identity,par ticularly regarding independence,and should foster their well-being in the clinical environment. 展开更多
关键词 HOPE identity INDEPENDENCE internsHIP nurse interns professional WELLNESS
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Knowledge,attitude and anxiety pertaining to basic life support and medical emergencies among dental interns in Mangalore City,India 被引量:2
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作者 Vinej Somaraj Rekha P Shenoy +3 位作者 Ganesh Shenoy Panchmal Praveen S Jodalli Laxminarayan Sonde Ravichandra Karkal 《World Journal of Emergency Medicine》 CAS 2017年第2期131-135,共5页
BACKGROUND: This cross-sectional study aimed to assess the knowledge, attitude and anxiety pertaining to basic life support(BLS) and medical emergencies among interns in dental colleges of Mangalore city, Karnataka, I... BACKGROUND: This cross-sectional study aimed to assess the knowledge, attitude and anxiety pertaining to basic life support(BLS) and medical emergencies among interns in dental colleges of Mangalore city, Karnataka, India.METHODS: The study subjects comprised of interns who volunteered from the four dental colleges. The knowledge and attitude of interns were assessed using a 30-item questionnaire prepared based on the Basic Life Support Manual from American Heart Association and the anxiety of interns pertaining to BLS and medical emergencies were assessed using a State-Trait Anxiety Inventory(STAI) Questionnaire. Chi-square test was performed on SPSS 21.0(IBM Statistics, 2012) to determine statistically signifi cant differences(P<0.05) between assessed knowledge and anxiety.RESULTS: Out of 183 interns, 39.89% had below average knowledge. A total of 123(67.21%) reported unavailability of professional training. The majority(180, 98.36%) felt the urgent need of training in basic life support procedures. Assessment of stress showed a total of 27.1% participants to be above highstress level. Comparison of assessed knowledge and stress was found to be insignifi cant(P=0.983).CONCLUSION: There was an evident lack of knowledge pertaining to the management of medical emergencies among the interns. As oral health care providers moving out to the society, a focus should be placed on the training of dental interns with respect to Basic Life Support procedures. 展开更多
关键词 Basic life support Cardiopulmonary resuscitation Dental interns Medical emergencies State-Trait anxiety inventory
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Practical Experience in Home Care of Nursing Interns: A Qualitative Research
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作者 Lin Wang Meijuan Luo +3 位作者 Ruiying Huang Yanying Zhu Zhili Chen Weiju Chen 《Open Journal of Nursing》 2020年第5期526-533,共8页
Purpose: To explore practical experience in home care of nursing interns. Methods: The phenomenological method for qualitative research was to interview 15 nursing interns in a semi-structured way, and then the collec... Purpose: To explore practical experience in home care of nursing interns. Methods: The phenomenological method for qualitative research was to interview 15 nursing interns in a semi-structured way, and then the collected data were analyzed and summarized by using the Colaizzi analysis method. Results: Interviewing results showed that there were five recurring themes, including: 1) personalized care;2) health education;3) humanistic care;4) solid professional foundation and sense of responsibility;5) expanded vision. Conclusion: Through home care practice, nursing interns deepened their cognitions of nursing connotation, stimulated their love for nursing and motivation of continuous learning, and improved their sense of identity to nursing career. In general, the practice of home care had a positive impact on nursing interns. 展开更多
关键词 NURSING interns HOME CARE PRACTICAL EXPERIENCE Qualitative RESEARCH
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Research on the Stress Management Strategies of Hotel Interns:A Case Study of Hotel Z in Foshan
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作者 Wei TANG Bingzhi HUANG 《Asian Agricultural Research》 2022年第1期38-40,59,共4页
In this study,by the combination of quantitative and qualitative research,the number of valid questionnaires was 217.The results show that there was a positive correlation between stress sources and stress response,an... In this study,by the combination of quantitative and qualitative research,the number of valid questionnaires was 217.The results show that there was a positive correlation between stress sources and stress response,and the four stress sources of own ability and quality,interpersonal relationship and communication,role requirements,work environment and atmosphere had a significant predictive effect on work pressure response;different personality characteristics had significant differences in the effect of work stress. 展开更多
关键词 Hotel industry interns Stress management Human resources
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Hospitality and Tourism International Internships and Perceived Employability
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作者 Greg Gannon 《Journal of Tourism and Hospitality Management》 2020年第4期161-174,共14页
This paper investigates the experiences of UK undergraduate students who have undertaken a one year paid internship abroad within the hotel sector by using a phenomenological approach.Semi-structured interviews were c... This paper investigates the experiences of UK undergraduate students who have undertaken a one year paid internship abroad within the hotel sector by using a phenomenological approach.Semi-structured interviews were conducted with 25 final year undergraduate students.The findings shed light on the alignment of key elements of the constructs of positive psychological capital and cosmopolitan human capital,along with strong self-belief in employability as a consequence of the experience.A theoretical model of international experience and positive psych-social development is postulated and contributes to improved practice in internship and employability mentoring and policy decision-making with respect to current internationalisation and employability agendas in the UK’s higher education system. 展开更多
关键词 internships INTERNATIONAL experience EMPLOYABILITY COSMOPOLITAN human CAPITAL positive psychological CAPITAL
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Effectiveness of a Structured Orientation Program for Medical Interns in Increasing the Awareness of Informed Consent
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作者 K Suprasanna R Anand +1 位作者 Sheetal Harakuni S R Ravikiran 《Journal of Forensic Science and Medicine》 2023年第3期264-270,共7页
Background:Informed consent has medicolegal implications and is imperative in presentday medical practice.Aims and Objectives:The objectives of this study were to estimate the awareness regarding informed consent in i... Background:Informed consent has medicolegal implications and is imperative in presentday medical practice.Aims and Objectives:The objectives of this study were to estimate the awareness regarding informed consent in interns and to determine the effectiveness of sessions in interns’orientation programs about informed consent.Materials and Methods:Pretest-Posttest study was conducted with a validated questionnaire distributed through Google Forms to interns attending the orientation program at our institute.Responses were recorded on the Likert scale(−2 to+2).Paired t-test was used to compare the mean pretest and posttest scores.The number of interns with a positive score(+1,+2)for every question in pretest and posttest were also compared.Results:One hundred and seventyone out of 232 interns who attended the program submitted both pretest and posttest responses.In the pretest,12 interns scored<50%and 46 interns scored more than 75%.A significant increase in posttest responses was seen in the mean score(P<0.001)and questions related to consent in research,radiological investigations,regarding the need for consent in the additional nonlifesaving procedure.There was an increase in the number of interns having a positive score(+1,+2)for all the questions in posttest as compared to pretest,but a statistically significant increase was seen in questions related to consent in ultrasound and need for consent in the additional nonlifesaving procedure.Conclusion:A wellstructured interns’orientation program is effective in improving awareness regarding consent.Certain gaps in knowledge regarding various aspects of consent need to be emphasized. 展开更多
关键词 Informed consent interns MEDICOLEGAL orientation program
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Assessment of International GNSS Service Global Ionosphere Map products over China region based on measurements from the Crustal Movement Observation Network of China 被引量:1
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作者 Jin Hu HaiBing Ruan +2 位作者 FuQing Huang ShengYang Gu XianKang Dou 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期400-407,共8页
The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of G... The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of GIM products in data-sparse regions is of paramount importance.In this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in 2013-2014.The indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM products.Results revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error variations.These results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions. 展开更多
关键词 International GNSS Service(IGS)Global Ionosphere Maps(GIM) Crustal Movement Observation Network of China(CMONOC) total electron content(TEC) data assessment
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Data-driven modeling on anisotropic mechanical behavior of brain tissue with internal pressure
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作者 Zhiyuan Tang Yu Wang +3 位作者 Khalil I.Elkhodary Zefeng Yu Shan Tang Dan Peng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期55-65,共11页
Brain tissue is one of the softest parts of the human body,composed of white matter and grey matter.The mechanical behavior of the brain tissue plays an essential role in regulating brain morphology and brain function... Brain tissue is one of the softest parts of the human body,composed of white matter and grey matter.The mechanical behavior of the brain tissue plays an essential role in regulating brain morphology and brain function.Besides,traumatic brain injury(TBI)and various brain diseases are also greatly influenced by the brain's mechanical properties.Whether white matter or grey matter,brain tissue contains multiscale structures composed of neurons,glial cells,fibers,blood vessels,etc.,each with different mechanical properties.As such,brain tissue exhibits complex mechanical behavior,usually with strong nonlinearity,heterogeneity,and directional dependence.Building a constitutive law for multiscale brain tissue using traditional function-based approaches can be very challenging.Instead,this paper proposes a data-driven approach to establish the desired mechanical model of brain tissue.We focus on blood vessels with internal pressure embedded in a white or grey matter matrix material to demonstrate our approach.The matrix is described by an isotropic or anisotropic nonlinear elastic model.A representative unit cell(RUC)with blood vessels is built,which is used to generate the stress-strain data under different internal blood pressure and various proportional displacement loading paths.The generated stress-strain data is then used to train a mechanical law using artificial neural networks to predict the macroscopic mechanical response of brain tissue under different internal pressures.Finally,the trained material model is implemented into finite element software to predict the mechanical behavior of a whole brain under intracranial pressure and distributed body forces.Compared with a direct numerical simulation that employs a reference material model,our proposed approach greatly reduces the computational cost and improves modeling efficiency.The predictions made by our trained model demonstrate sufficient accuracy.Specifically,we find that the level of internal blood pressure can greatly influence stress distribution and determine the possible related damage behaviors. 展开更多
关键词 Data driven Constitutive law ANISOTROPY Brain tissue Internal pressure
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Correction to:Error Calculation of Large-Amplitude Internal Solitary Waves Within the Pycnocline Introduced by the Strong Stratification Approximation
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作者 Cunguo Xu Zhan Wang Masoud Hayatdavoodi 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第1期247-247,共1页
In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correc... In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correction. 展开更多
关键词 STRONG Internal CORRECTION
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Alkali Tolerance of Concrete Internal Curing Agent Based on Sodium Carboxymethyl Starch
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作者 陈梅花 刘荣进 +3 位作者 CHEN Ping JING Daiyan WAN Dandan FU Siyuan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期82-90,共9页
Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using ... Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw materials.The results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali environment.The water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is 3.4.The application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore structure.The compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength. 展开更多
关键词 alkali tolerance sodium carboxymethyl starch internal curing agent compressive strength
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Equivalence between the internal observability and equation
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作者 LIU Wen-jun TU Zhi-yu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期89-97,共9页
This paper is concerned with a third order in time linear Moore-Gibson-Thompson equation which describes the acoustic velocity potential in ultrasound wave program.Influenced by the work of Kaltenbacher,Lasiecka and M... This paper is concerned with a third order in time linear Moore-Gibson-Thompson equation which describes the acoustic velocity potential in ultrasound wave program.Influenced by the work of Kaltenbacher,Lasiecka and Marchand(Control Cybernet.2011,40:971-988),we establish an observability inequality of the conservative problem,and then discuss the equivalence between the exponential stabilization of a dissipative system and the internal observational inequality of the corresponding conservative system. 展开更多
关键词 Moore-Gibson-Thompson equation internal observability exponential stability
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Mechanism of internal thermal runaway propagation in blade batteries
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作者 Xuning Feng Fangshu Zhang +3 位作者 Wensheng Huang Yong Peng Chengshan Xu Minggao Ouyang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期184-194,I0005,共12页
Blade batteries are extensively used in electric vehicles,but unavoidable thermal runaway is an inherent threat to their safe use.This study experimentally investigated the mechanism underlying thermal runaway propaga... Blade batteries are extensively used in electric vehicles,but unavoidable thermal runaway is an inherent threat to their safe use.This study experimentally investigated the mechanism underlying thermal runaway propagation within a blade battery by using a nail to trigger thermal runaway and thermocouples to track its propagation inside a cell.The results showed that the internal thermal runaway could propagate for up to 272 s,which is comparable to that of a traditional battery module.The velocity of the thermal runaway propagation fluctuated between 1 and 8 mm s^(-1),depending on both the electrolyte content and high-temperature gas diffusion.In the early stages of thermal runaway,the electrolyte participated in the reaction,which intensified the thermal runaway and accelerated its propagation.As the battery temperature increased,the electrolyte evaporated,which attenuated the acceleration effect.Gas diffusion affected thermal runaway propagation through both heat transfer and mass transfer.The experimental results indicated that gas diffusion accelerated the velocity of thermal runaway propagation by 36.84%.We used a 1D mathematical model and confirmed that convective heat transfer induced by gas diffusion increased the velocity of thermal runaway propagation by 5.46%-17.06%.Finally,the temperature rate curve was analyzed,and a three-stage mechanism for internal thermal runaway propagation was proposed.In Stage I,convective heat transfer from electrolyte evaporation locally increased the temperature to 100℃.In Stage II,solid heat transfer locally increases the temperature to trigger thermal runaway.In StageⅢ,thermal runaway sharply increases the local temperature.The proposed mechanism sheds light on the internal thermal runaway propagation of blade batteries and offers valuable insights into safety considerations for future design. 展开更多
关键词 Lithium-ion battery Blade battery Thermal runaway Internal thermal runaway propagation
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Multi-Stage Multidisciplinary Design Optimization Method for Enhancing Complete Artillery Internal Ballistic Firing Performance
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作者 Jipeng Xie Guolai Yang +1 位作者 Liqun Wang Lei Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期793-819,共27页
To enhance the comprehensive performance of artillery internal ballistics—encompassing power,accuracy,and service life—this study proposed a multi-stage multidisciplinary design optimization(MS-MDO)method.First,the ... To enhance the comprehensive performance of artillery internal ballistics—encompassing power,accuracy,and service life—this study proposed a multi-stage multidisciplinary design optimization(MS-MDO)method.First,the comprehensive artillery internal ballistic dynamics(AIBD)model,based on propellant combustion,rotation band engraving,projectile axial motion,and rifling wear models,was established and validated.This model was systematically decomposed into subsystems from a system engineering perspective.The study then detailed the MS-MDO methodology,which included Stage I(MDO stage)employing an improved collaborative optimization method for consistent design variables,and Stage II(Performance Optimization)focusing on the independent optimization of local design variables and performance metrics.The methodology was applied to the AIBD problem.Results demonstrated that the MS-MDO method in Stage I effectively reduced iteration and evaluation counts,thereby accelerating system-level convergence.Meanwhile,Stage II optimization markedly enhanced overall performance.These comprehensive evaluation results affirmed the effectiveness of the MS-MDO method. 展开更多
关键词 ARTILLERY internal ballistics dynamics multi-stage optimization multi-disciplinary design optimization collaborative optimization
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An internal ballistic model of electromagnetic railgun based on PFN coupled with multi-physical field and experimental validation
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作者 Benfeng Gu Haiyuan Li Baoming Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期254-261,共8页
To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore damage.In this paper,a three-dime... To accelerate the practicality of electromagnetic railguns,it is necessary to use a combination of threedimensional numerical simulation and experiments to study the mechanism of bore damage.In this paper,a three-dimensional numerical model of the augmented railgun with four parallel unconventional rails is introduced to simulate the internal ballistic process and realize the multi-physics field coupling calculation of the rail gun,and a test experiment of a medium-caliber electromagnetic launcher powered by pulse formation network(PFN)is carried out.Various test methods such as spectrometer,fiber grating and high-speed camera are used to test several parameters such as muzzle initial velocity,transient magnetic field strength and stress-strain of rail.Combining the simulation results and experimental data,the damage condition of the contact surface is analyzed. 展开更多
关键词 Internal ballistic modeling Electromagnetic rail gun Multi-physics field coupling Experimental validation PFN
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Utilization of Basalt Saw Mud as a Spherical Porous Functional Aggregate for the Preparation of Ordinary Structure Concrete
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作者 周永祥 关青锋 +2 位作者 LENG Faguang WANG Jing LI Tianjun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期364-375,共12页
To promote the production and application of artificial aggregates,save natural sand resources and protect the ecological environment,we evaluated the feasibility of using spherical porous functional aggregates(SPFAs)... To promote the production and application of artificial aggregates,save natural sand resources and protect the ecological environment,we evaluated the feasibility of using spherical porous functional aggregates(SPFAs) formed by basalt saw mud under autoclave curing in ordinary structural concrete.In our work,two types of prewetted functional aggregates were taken as replacements for natural aggregates with different volume substitution rates(0%,5%,10%,15%,20%,25%,and 30%) in the preparation of ordinary structural concrete with water-to-binder ratios(W/B) of 0.48 and 0.33.The effects of the functional aggregate properties and content,W/B,and curing age on the fluidity,density,mechanical properties and autogenous shrinkage of ordinary concrete were analyzed.The experimental results showed that the density of concrete declined at a rate of not more than 5%,and the 28 d compressive strength could reach 31.0-68.2 MPa.Low W/B,long curing age and high-quality functional aggregates were conducive to enhancing the mechanical properties of SPFAs concrete.Through the rolling effects,SPFAs can optimize the particle gradation of aggregate systems and improve the fluidity of concrete,and the water stored inside SPFAs provides an internal curing effect,which prolongs the cement hydration process and considerably reduces the autogenous shrinkage of concrete.SPFAs exhibits high strength and high density,as well as being more cost-effective and ecological,and is expected to be widely employed in ordinary structural concrete. 展开更多
关键词 lightweight concrete civil concrete building basalt saw mud fly ash internal curing environmentally friendly
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Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing
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作者 Jay Kumar Shah Hao Wang Said El-Hawwat 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期319-329,共11页
Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.The growth of internal cracks in PE pipe seve... Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.The growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance strategies.This study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE pipe.Laboratory experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch configuration.Mode dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack growth.The findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth. 展开更多
关键词 polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling
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