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Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints 被引量:1
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作者 Jin-Xi Zhang Kai-Di Xu Qing-Guo Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1557-1565,共9页
The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requ... The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this paper.Herein, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings. 展开更多
关键词 Nonlinear systems output constraints prescribed performance reference tracking time delays
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A Systematic Literature Review on Task Allocation and Performance Management Techniques in Cloud Data Center
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作者 Nidhika Chauhan Navneet Kaur +5 位作者 Kamaljit Singh Saini Sahil Verma Abdulatif Alabdulatif Ruba Abu Khurma Maribel Garcia-Arenas Pedro A.Castillo 《Computer Systems Science & Engineering》 2024年第3期571-608,共38页
As cloud computing usage grows,cloud data centers play an increasingly important role.To maximize resource utilization,ensure service quality,and enhance system performance,it is crucial to allocate tasks and manage p... As cloud computing usage grows,cloud data centers play an increasingly important role.To maximize resource utilization,ensure service quality,and enhance system performance,it is crucial to allocate tasks and manage performance effectively.The purpose of this study is to provide an extensive analysis of task allocation and performance management techniques employed in cloud data centers.The aim is to systematically categorize and organize previous research by identifying the cloud computing methodologies,categories,and gaps.A literature review was conducted,which included the analysis of 463 task allocations and 480 performance management papers.The review revealed three task allocation research topics and seven performance management methods.Task allocation research areas are resource allocation,load-Balancing,and scheduling.Performance management includes monitoring and control,power and energy management,resource utilization optimization,quality of service management,fault management,virtual machine management,and network management.The study proposes new techniques to enhance cloud computing work allocation and performance management.Short-comings in each approach can guide future research.The research’s findings on cloud data center task allocation and performance management can assist academics,practitioners,and cloud service providers in optimizing their systems for dependability,cost-effectiveness,and scalability.Innovative methodologies can steer future research to fill gaps in the literature. 展开更多
关键词 Cloud computing data centre task allocation performance management resource utilization
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The Impact of Health Information Technology on Hospital Performance: A Systematic Integrative Literature Review
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作者 Alisa Westerhof Cokky Hilhorst Willem Jan Bos 《Health》 2024年第4期257-279,共23页
Objective: To review, categorise, and synthesise findings from literature on health information technology (HIT) functionalities, HIT use, and the impact of HIT on hospital performance. Materials and Methods: We condu... Objective: To review, categorise, and synthesise findings from literature on health information technology (HIT) functionalities, HIT use, and the impact of HIT on hospital performance. Materials and Methods: We conducted a systematic integrative literature review based on a compre-hensive database search. To organise, categorise and synthesise the ex-isting literature, we adopted the affordance actualization theory. To align the literature with our research framework, we used four categories: 1) the functionalities of HIT and how these functionalities are measured;2) use and immediate outcomes of HIT functionalities;3) different perfor-mance indicators and how HIT functionalities affect them;and 4) what hospital characteristics influence the outcome of hospital performance. Results: Fifty-two studies were included. We identified four types of HIT. Only ten studies (19.2%) define the use of HIT by explicitly meas-uring the use rate of HIT. We identified five dimensions of hospital per-formance indicators. Every dimension showed mixed results;however, in general, HIT has a positive impact on mortality and patient readmis-sions. We found several hospital characteristics that may affect the rela-tionship between HIT and hospital-level outcomes. Discussion: Further efforts should focus on embedded research on HIT functionalities, use and effects of HIT implementations with more performance indicators and adjusted for hospital characteristics. Conclusion: The proposed framework could help hospitals and researchers make decisions regard-ing the functionalities, use and effects of HIT implementation in hospi-tals. Given our research outcomes, we suggest future research opportuni-ties to improve understanding of how HIT affects hospital performance. . 展开更多
关键词 Health Information Technology HIT Functionalities Hospital performance Indicators
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Etiology and management of urethral calculi:A systematic review of contemporary series
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作者 Andrew Morton Arsalan Tariq +2 位作者 Nigel Dunglison Rachel Esler Matthew J.Roberts 《Asian Journal of Urology》 CSCD 2024年第1期10-18,共9页
Objective:To conduct a systematic literature review on urethral calculi in a contemporary cohort describing etiology,investigation,and management patterns.Methods:A systematic search of MEDLINE and Cochrane Central Re... Objective:To conduct a systematic literature review on urethral calculi in a contemporary cohort describing etiology,investigation,and management patterns.Methods:A systematic search of MEDLINE and Cochrane Central Register of Controlled Trials(CENTRAL)databases was performed.Articles,including case reports and case series on urethral calculi published between January 2000 and December 2019,were included.Full-text manuscripts were reviewed for clinical parameters including symptomatology,etiology,medical history,investigations,treatment,and outcomes.Data were collated and analyzed with univariate methods.Results:Seventy-four publications met inclusion criteria,reporting on 95 cases.Voiding symptoms(41.1%),pain(40.0%),and acute urinary retention(32.6%)were common presenting features.Urethral calculi were most often initially investigated using plain X-ray(63.2%),with almost all radio-opaque(98.3%).Urethral calculi were frequently associated with coexistent bladder or upper urinary tract calculi(16.8%)and underlying urethral pathology(53.7%)including diverticulum(33.7%)or stricture(13.7%).Urethral calculi were most commonly managed with external urethrolithotomy(31.6%),retrograde manipulation(22.1%),and endoscopic in situ lithotripsy(17.9%).Conclusion:This unique systematic review of urethral calculi provided a summary of clinical features and treatment trends with a suggested treatment algorithm.Management in contemporary urological practice should be according to calculus size,shape,anatomical location,and presence of urethral pathology. 展开更多
关键词 Urinary calculi URETHRA Urethral calculi management algorithm
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Dynamic performance and parameter optimization of a half-vehicle system coupled with an inerter-based X-structure nonlinear energy sink
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作者 Yong WANG Peili WANG +1 位作者 Haodong MENG Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期85-110,共26页
Inspired by the demand of improving the riding comfort and meeting the lightweight design of the vehicle, an inerter-based X-structure nonlinear energy sink(IXNES) is proposed and applied in the half-vehicle system to... Inspired by the demand of improving the riding comfort and meeting the lightweight design of the vehicle, an inerter-based X-structure nonlinear energy sink(IXNES) is proposed and applied in the half-vehicle system to enhance the dynamic performance. The X-structure is used as a mechanism to realize the nonlinear stiffness characteristic of the NES, which can realize the flexibility, adjustability, high efficiency, and easy operation of nonlinear stiffness, and is convenient to apply in the vehicle suspension, and the inerter is applied to replacing the mass of the NES based on the mass amplification characteristic. The dynamic model of the half-vehicle system coupled with the IX-NES is established with the Lagrange theory, and the harmonic balance method(HBM) and the pseudo-arc-length method(PALM) are used to obtain the dynamic response under road harmonic excitation. The corresponding dynamic performance under road harmonic and random excitation is evaluated by six performance indices, and compared with that of the original half-vehicle system to show the benefits of the IX-NES. Furthermore, the structural parameters of the IX-NES are optimized with the genetic algorithm. The results show that for road harmonic and random excitation, using the IX-NES can greatly reduce the resonance peaks and root mean square(RMS) values of the front and rear suspension deflections and the front and rear dynamic tire loads, while the resonance peaks and RMS values of the vehicle body vertical and pitching accelerations are slightly larger.When the structural parameters of the IX-NES are optimized, the vehicle body vertical and pitching accelerations of the half-vehicle system could reduce by 2.41% and 1.16%,respectively, and the other dynamic performance indices are within the reasonable ranges.Thus, the IX-NES combines the advantages of the inerter, X-structure, and NES, which improves the dynamic performance of the half-vehicle system and provides an effective option for vibration attenuation in the vehicle engineering. 展开更多
关键词 inerter X-structure nonlinear energy sink(NES) half-vehicle system dynamic performance
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Ethics of Human Resources Management in the Cameroonian Health System, Medical Nomadism and the Ineffectiveness of the Fight against High Blood Pressure
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作者 Jean Ndibi Abanda Anicet Onana Akoa +2 位作者 Désiré Tchoffo Ulrich Dama Pierre Yassa Yoniene 《Health》 2024年第1期9-21,共13页
Context/objectives: The fight against Chronic Non-Communicable Diseases (NCDs) is a long-term undertaking, which requires available, motivated and well-managed human resources (HR). The administrative management of sk... Context/objectives: The fight against Chronic Non-Communicable Diseases (NCDs) is a long-term undertaking, which requires available, motivated and well-managed human resources (HR). The administrative management of skills on both qualitative and quantitative levels is one of the essential functions of a health system. To better implement policies of fight against High Blood Pressure (HBP) and other chronic diseases, it is important to establish strategies to retain health personnel. This loyalty requires favorable working conditions and consideration of the contribution-reward couple. Good working conditions are likely to reduce the phenomenon of medical nomadism;conversely, poor HR management can contribute to their exodus towards exotic “green pastures”, thus leading to an additional crisis in the Cameroonian health system. The fight against HBP is a complex, multifaceted and multifactorial reality that requires appropriate management model for all types of resources mainly HR. The main objective of this research is to show the impact of poor management of human resources in Cameroon health system on medical nomadism and the ineffectiveness of the fight against High Blood Pressure. Method: A cross-sectional descriptive survey among five hundred (500) health facilities in the center region of Cameroon has been conducted. A stratified probabilistic technique has been used, and the number of health facilities to be surveyed has been determined using the “sample size estimation table” of Depelteau. The physical questionnaires have been printed and then distributed to data collectors. After data collection, the latter were grouped during processing in Excel sheets. The Chi-square test was used for data with a qualitative value and that of Kolmogorov-Sminorf for data with a quantitative value to assess the normality and reliability of data. The Crochach’s Alpha reliability test allowed us to have a summary of the means and variances and then to search for intragroup correlations between variables. Descriptive analysis was possible with the XLSTAT 2016 software. Results: 43.60% of Health Facilities (HF) managers were unqualified. 82.20% of HF managers have staff in a situation of professional insecurity. They are mainly contractual (49.00), decision-making agents (24.40%), casual agents (08.80). The proportion of unstable personnel is average of 22.00% and very unstable, 12.00%. 展开更多
关键词 ETHICS Human Resources management Cameroonian Health system Medical Nomadism Ineffectiveness High Blood Pressure
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Reinforcement Learning-Based Energy Management for Hybrid Power Systems:State-of-the-Art Survey,Review,and Perspectives
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作者 Xiaolin Tang Jiaxin Chen +4 位作者 Yechen Qin Teng Liu Kai Yang Amir Khajepour Shen Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期1-25,共25页
The new energy vehicle plays a crucial role in green transportation,and the energy management strategy of hybrid power systems is essential for ensuring energy-efficient driving.This paper presents a state-of-the-art ... The new energy vehicle plays a crucial role in green transportation,and the energy management strategy of hybrid power systems is essential for ensuring energy-efficient driving.This paper presents a state-of-the-art survey and review of reinforcement learning-based energy management strategies for hybrid power systems.Additionally,it envisions the outlook for autonomous intelligent hybrid electric vehicles,with reinforcement learning as the foundational technology.First of all,to provide a macro view of historical development,the brief history of deep learning,reinforcement learning,and deep reinforcement learning is presented in the form of a timeline.Then,the comprehensive survey and review are conducted by collecting papers from mainstream academic databases.Enumerating most of the contributions based on three main directions—algorithm innovation,powertrain innovation,and environment innovation—provides an objective review of the research status.Finally,to advance the application of reinforcement learning in autonomous intelligent hybrid electric vehicles,future research plans positioned as“Alpha HEV”are envisioned,integrating Autopilot and energy-saving control. 展开更多
关键词 New energy vehicle Hybrid power system Reinforcement learning Energy management strategy
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Design and Implementation of Library Seating Management System
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作者 Pengxian Liu 《Journal of Computer and Communications》 2024年第8期292-306,共15页
The library seating management system is an important part of the library’s modern services. The system is based on the Spring and Spring Boot framework, and the system realizes a series of functions such as real-tim... The library seating management system is an important part of the library’s modern services. The system is based on the Spring and Spring Boot framework, and the system realizes a series of functions such as real-time query, reservation, and cancellation of seat resources, providing users with great convenience. With a simple operation, users can know the availability of seats in the library in real time and reserve them according to their needs. At the same time, the system also provides rich management functions, enabling administrators to easily configure and manage seat resources. The addition, deletion, modification and review of users, the generation of seats, the viewing of user usage records, and the addition or deletion of points for users’ usage can also be carried out. This not only improves the management efficiency, but also provides more scientific and accurate data support for the management of the library. The system not only optimizes the user experience, but also promotes the scientific management and efficient utilization of library resources, and provides strong support for the modern services of the library. 展开更多
关键词 LIBRARY Seats management system Design management Efficiency SPRING
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Water and nitrogen footprint assessment of integrated agronomic practice management in a summer maize cropping system
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作者 Ningning Yu Bingshuo Wang +3 位作者 Baizhao Ren Bin Zhao Peng Liu Jiwang Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3610-3621,共12页
The footprints of water and nitrogen(WF and NF)provide a comprehensive overview of the type and quantity of water consumption and reactive nitrogen(Nr)loss in crop production.In this study,a field experiment over two ... The footprints of water and nitrogen(WF and NF)provide a comprehensive overview of the type and quantity of water consumption and reactive nitrogen(Nr)loss in crop production.In this study,a field experiment over two years(2019 and 2020)compared three integrated agronomic practice management(IAPM)systems:An improved management system(T2),a high-yield production system(T3),and an integrated soil-crop management system(ISCM)using a local smallholder farmer’s practice system(T1)as control,to investigate the responses of WF,Nr losses,water use efficiency(WUE),and nitrogen use efficiency(NUE)to IAPM.The results showed that IAPM optimized water distribution and promoted water use by summer maize.The evapotranspiration over the whole maize growth period of IAPM increased,but yield increased more,leading to a significant increase in WUE.The WUE of the T2,T3,and ISCM treatments was significantly greater than in the T1 treatment,in 2019 and 2020respectively,by 19.8-21.5,31.8-40.6,and 34.4-44.6%.The lowest WF was found in the ISCM treatment,which was 31.0%lower than that of the T1 treatment.In addition,the ISCM treatment optimized soil total nitrogen(TN)distribution and significantly increased TN in the cultivated layer.Excessive nitrogen fertilizer was applied in treatment T3,producing the highest maize yield,and resulting in the highest Nr losses.In contrast,the ISCM treatment used a reduced nitrogen fertilizer rate,sacrificing grain yield partly,which reduced Nr losses and eventually led to a significant increase in nitrogen use efficiency and nitrogen recovery.The Nr level in the ISCM treatment was34.8%lower than in the T1 treatment while NUE was significantly higher than in the T1 treatment by 56.8-63.1%in2019 and 2020,respectively.Considering yield,WUE,NUE,WF,and NF together,ISCM should be used as a more sustainable and clean system for sustainable production of summer maize. 展开更多
关键词 integrated agronomic practice management water footprints nitrogen footprints water use efficiency nitrogen use efficiency yield
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Regenerative Braking Energy Recovery System ofMetro Train Based on Dual-Mode PowerManagement
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作者 Feng Zhao Xiaotong Zhu +1 位作者 Xiaoqiang Chen Ying Wang 《Energy Engineering》 EI 2024年第9期2585-2601,共17页
In order to fully utilize the regenerative braking energy of metro trains and stabilize the metro DC traction busbar voltage,a hybrid regenerative braking energy recovery system with a dual-mode power management strat... In order to fully utilize the regenerative braking energy of metro trains and stabilize the metro DC traction busbar voltage,a hybrid regenerative braking energy recovery system with a dual-mode power management strategy is proposed.Firstly,the construction of the hybrid regenerative braking energy recovery system is explained.Then,based on the power demand of low-voltage load in metro stations,a dual-mode power management strategy is proposed to allocate the reference power of each system according to the different working conditions,and the control methods of each system are set.Finally,the correctness and effectiveness of the dual-mode strategy are verified through simulation,and the proposed braking energy utilization scheme is compared with other singleform utilization schemes.The results illustrate that the hybrid system with the dual-mode strategy can effectively recycle the regenerative braking energy of metro train and inhibit the busbar voltage fluctuation;the proposed braking energy utilization scheme has certain advantages on energy recovery and DC bus voltage stabilization compared with other single-form schemes;the proposed power management strategy can correctly allocate the reference power of each system with a lower construction cost. 展开更多
关键词 Metro train regenerative braking energy energy feed-back system energy storage system power management
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Development and Application of Integrated Indicators for Assessing Healthcare Waste Management Systems in Kenyan Hospitals
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作者 Muriithi Jackson Githinji Paul Mwangi Njogu +1 位作者 Zipporah Nganga Mohamed Karama 《Open Journal of Applied Sciences》 2024年第4期1080-1120,共41页
Healthcare waste management (HCWM) is an important aspect of healthcare delivery globally because of its hazardous and infectious components that have potential for adverse health and environmental impacts. The paper ... Healthcare waste management (HCWM) is an important aspect of healthcare delivery globally because of its hazardous and infectious components that have potential for adverse health and environmental impacts. The paper introduces a set of indicators for assessing HCWM systems in hospitals. These indicators are: HCWM policies and standard operating procedures, management and oversight, logistics and budget support, training and occupational health and safety, and treatment, disposal and waste treatment equipment housing. By plotting a mark on a continuum which is defined as good and poor on the extremes and is connected with all other marks in a spoke arrangement, it’s possible to describe a baseline for HCWM in any specific hospital. This baseline can be used to improve awareness of the actors and policy-makers, compare the same hospital at a different point in time, to compare observations by different evaluators and to track improvements. Results suggest that in Kenya, the application of such indicators is useful for evaluating which priorities should be addressed to improve outcomes in HCWM systems. Systematic sampling technique was used to identify and collect data by use of observational checklist, interviews, visual verification and review of documents and a HCWM assessment tool. The objective is to suggest an integrated management tool as a method to identify prevailing problems with a HCWM system. The method can be replicated in other contexts worldwide, with a focus on the developing world. The integrated indicators focus on management of HCW and not its potential impact on human health and environment, an area recognized to be critical for future research. 展开更多
关键词 Developing Countries HCW management Indicators management Tools
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Improvement of the nutritional support management system for patients in intensive care units
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作者 Yuan-Yuan Zhang Chun-Yi Wang +5 位作者 Dong-Xian Guo Hai-Nu Gao Xian-Shan Jin Yan-Li Wu Lu-Han Chen Zhi-Xian Feng 《World Journal of Psychiatry》 SCIE 2024年第1期44-52,共9页
BACKGROUND Nutritional support for patients hospitalized in the intensive care unit(ICU)is an important part of clinical treatment and care,but there are significant implementation difficulties.AIM To introduce a modi... BACKGROUND Nutritional support for patients hospitalized in the intensive care unit(ICU)is an important part of clinical treatment and care,but there are significant implementation difficulties.AIM To introduce a modified nutritional support management system for ICU patients based on closed-loop information management and psychological counseling.METHODS The division of functions,personnel training,system construction,development of an intelligent decision-making software system,quality control,and improvement of the whole process were carried out to systematically manage nutritional support for ICU patients.RESULTS Following the implementation of the whole process management system,the scores of ICU medical staff’s knowledge,attitudes/beliefs,and practices regarding nutritional support were comprehensively enhanced.The proportion of hospital bed-days of total enteral nutrition(EN)in ICU patients increased from 5.58%to 11.46%,and the proportion of EN plus parenteral nutrition increased from 42.71%to 47.07%.The rate of EN initiation within 48 h of ICU admission increased from 37.50%to 48.28%,and the EN compliance rate within 72 h elevated from 20.59%to 31.72%.After the implementation of the project,the Self-rating Anxiety Scale score decreased from 61.07±9.91 points to 52.03±9.02 points,the Self-rating Depression Scale score reduced from 62.47±10.50 points to 56.34±9.83 points,and the ICU stay decreased from 5.76±2.77 d to 5.10±2.12 d.CONCLUSION The nutritional support management system based on closed-loop information management and psychological counseling achieved remarkable results in clinical applications in ICU patients. 展开更多
关键词 Closed-loop information Psychological counseling Intensive care unit patients Nutritional support management system
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Seismic performance evaluation of hybrid coupled shear wall system with shear and flexural fuse-type steel coupling beams
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作者 Zahra Ramezandoust Abbas Tajaddini Panam Zarfam 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期691-712,共22页
Replaceable flexural and shear fuse-type coupling beams are used in hybrid coupled shear wall(HCSW)systems,enabling concrete buildings to be promptly recovered after severe earthquakes.This study aimed to analytically... Replaceable flexural and shear fuse-type coupling beams are used in hybrid coupled shear wall(HCSW)systems,enabling concrete buildings to be promptly recovered after severe earthquakes.This study aimed to analytically evaluate the seismic behavior of flexural and shear fuse beams situated in short-,medium-and high-rise RC buildings that have HCSWs.Three building groups hypothetically located in a high seismic hazard zone were studied.A series of 2D nonlinear time history analyses was accomplished in OpenSees,using the ground motion records scaled at the design basis earthquake level.It was found that the effectiveness of fuses in HCSWs depends on various factors such as size and scale of the building,allowable rotation value,inter-story drift ratio,residual drift quantity,energy dissipation value of the fuses,etc.The results show that shear fuses better meet the requirements of rotations and drifts.In contrast,flexural fuses dissipate more energy,but their sectional stiffness should increase to meet other requirements.It was concluded that adoption of proper fuses depends on the overall scale of the building and on how associated factors are considered. 展开更多
关键词 hybrid coupled shear wall steel fuse coupling beam shear and flexural fuse nonlinear dynamic analysis seismic performance
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Systematic review of risk factors,prognosis,and management of colorectal signet-ring cell carcinoma
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作者 Frederiek Nuytens Vincent Drubay +2 位作者 Clarisse Eveno Florence Renaud Guillaume Piessen 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期2141-2158,共18页
BACKGROUND Colorectal signet-ring cell carcinoma(CSRCC)is a rare clinical entity which accounts for approximately 1%of all colorectal cancers.Although multiple studies concerning this specific topic have been publishe... BACKGROUND Colorectal signet-ring cell carcinoma(CSRCC)is a rare clinical entity which accounts for approximately 1%of all colorectal cancers.Although multiple studies concerning this specific topic have been published in the past decades,the pathogenesis,associated risk factors,and potential implications on treatment are still poorly understood.Besides the low incidence,historically confusing histological criteria have resulted in confusing data.Nevertheless,the rising incidence of CSRCC along with relatively young age at presentation and associated dismal prognosis,highlight the actual interest to synthesize the known literature regarding CSRCC.AIM To provide an updated overview of risk factors,prognosis,and management of CSRCC.METHODS A literature search in the MEDLINE/PubMed database was conducted with the following search terms used:‘Signet ring cell carcinoma’and‘colorectal’.Studies in English language,published after January 1980,were included.Studies included in the qualitative synthesis were evaluated for content concerning epidemiology,risk factors,and clinical,diagnostic,histological,and molecular features,as well as metastatic pattern and therapeutic management.If possible,presented data was extracted in order to present a more detailed overview of the literature.RESULTS In total,67 articles were included for qualitative analysis,of which 54 were eligible for detailed data extraction.CSRCC has a reported incidence between 0.1%-2.4%and frequently presents with advanced disease stage at the time of diagnosis.CSRCC is associated with an impaired overall survival(5-year OS:0%-46%)and a worse stagecorrected outcome compared to mucinous and not otherwise specified adenocarcinoma.The systematic use of exploratory laparoscopy to determine the presence of peritoneal metastases has been advised.Surgery is the mainstay of treatment,although the rates of curative resection in CSRCC(21%-82%)are lower compared to those in other histological types.In case of peritoneal metastasis,cytoreductive surgery with hyperthermic intraperitoneal chemotherapy should only be proposed in selected patients.CONCLUSION CSRCC is a rare clinical entity most often characterized by young age and advanced disease at presentation.As such,diagnostic modalities and therapeutic approach should be tailored accordingly. 展开更多
关键词 Colorectal cancer Signet-ring cell histology Poorly cohesive cells systematic review Risk factors PROGNOSIS Therapeutic management
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Correlation Study of Operational Data and System Performance of District Cooling System with Ice Storage
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作者 Hui Cao Nan Li Jiajing Lin 《Journal of Power and Energy Engineering》 2024年第3期75-98,共24页
The district cooling system (DCS) with ice storage can reduce the peak electricity demand of the business district buildings it serves, improve system efficiency, and lower operational costs. This study utilizes a mon... The district cooling system (DCS) with ice storage can reduce the peak electricity demand of the business district buildings it serves, improve system efficiency, and lower operational costs. This study utilizes a monitoring and control platform for DCS with ice storage to analyze historical parameter values related to system operation and executed operations. We assess the distribution of cooling loads among various devices within the DCS, identify operational characteristics of the system through correlation analysis and principal component analysis (PCA), and subsequently determine key parameters affecting changes in cooling loads. Accurate forecasting of cooling loads is crucial for determining optimal control strategies. The research process can be summarized briefly as follows: data preprocessing, parameter analysis, parameter selection, and validation of load forecasting performance. The study reveals that while individual devices in the system perform well, there is considerable room for improving overall system efficiency. Six principal components have been identified as input parameters for the cold load forecasting model, with each of these components having eigenvalues greater than 1 and contributing to an accumulated variance of 87.26%, and during the dimensionality reduction process, we obtained a confidence ellipse with a 95% confidence interval. Regarding cooling load forecasting, the Relative Absolute Error (RAE) value of the light gradient boosting machine (lightGBM) algorithm is 3.62%, Relative Root Mean Square Error (RRMSE) is 42.75%, and R-squared value (R<sup>2</sup>) is 92.96%, indicating superior forecasting performance compared to other commonly used cooling load forecasting algorithms. This research provides valuable insights and auxiliary guidance for data analysis and optimizing operations in practical engineering applications. . 展开更多
关键词 DCS Correlation Coefficient PCA Hourly Cooling Load system performance
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An Assessment of Procurement Risks Management Systems in the Public Sector
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作者 Atoapem Frimpong Barimah Joyce-Jael Amoafoa Mensah 《Chinese Business Review》 2024年第2期76-86,共11页
Risk management in public procurement is a critical aspect that needs to be addressed in the public sector.Several studies have been conducted to understand the challenges and factors influencing risk management in pu... Risk management in public procurement is a critical aspect that needs to be addressed in the public sector.Several studies have been conducted to understand the challenges and factors influencing risk management in public procurement.These studies have explored the importance of risk management principles,the role of political influence,and the need for effective risk assessment and anticipation.The research has also highlighted the need for specific risk management mechanisms and tools to be implemented in public procurement processes.Risk management reforms in the public sector are essential but often circumvented due to assorted reasons,such as political influence and the emergence of new risks.The research investigation employs a quantitative research design.A total of 380 questionnaires were recovered from respondents.The study showed that the public sector has a procurement risk management system that is effective,but there may be some areas for improvement in the prequalification process,onboarding process,and support provided to newly onboarded suppliers.Additionally,the public sector used some strategies to mitigate and control contract risks during the procurement process,but there were some areas for improvement in the review and lessons learned process,risk mitigation measures,contract monitoring and performance evaluation mechanisms,and communication and documentation process.Finally,the results suggest that there were constraints placed on the risk management strategies currently utilized by professionals working in the public sector.These constraints include insufficient support and buy-in from senior management and stakeholders,bureaucratic or administrative hurdles,inadequate policies and regulations,insufficient training and skill development opportunities,and insufficient resources.The study highlights the significance of tackling risk management in the realm of public procurement and offers valuable perspectives on avenues for enhancement,obstacles encountered by practitioners,and the necessity of thorough evaluation and revisions.Through the adoption of the suggestions originating from this study,governmental entities can improve their procurement risk management frameworks and guarantee improved adherence to risk management principles. 展开更多
关键词 public sector public procurement SUPPLIERS risk management STRATEGIES
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Comparison of German and American Higher Education Accreditation Systems and Implications for Quality Management of Higher Education in China
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作者 LI Qin-yao 《Journal of Literature and Art Studies》 2024年第6期491-508,共18页
At the present stage,China’s higher education has experienced continuous reform and enhancement,the scale of education has jumped to the forefront,and the quality of education has been continuously improved,which has... At the present stage,China’s higher education has experienced continuous reform and enhancement,the scale of education has jumped to the forefront,and the quality of education has been continuously improved,which has made gratifying achievements.The development of China’s higher education has entered the critical node of improving quality and efficiency,and the importance of quality management as the central link in improving the quality of higher education is self-evident.Accreditation as an effective means of quality assurance,in Germany and the United States has formed a mature and perfect system and procedures.Therefore,analysing and learning from the quality management system of higher education in Germany and the United States has an important reference value for promoting the further development of quality management of higher education in China. 展开更多
关键词 accreditation systems quality management in higher education GERMANY USA
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Towards Automated Assessment of Learning Management Systems in Higher Education Institutions in Zambia
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作者 Memory Mumbi Mayumbo Nyirenda 《Open Journal of Applied Sciences》 2024年第5期1279-1294,共16页
Zambia like any other country in most African regions is still grappling with the dynamics of harnessing technology for the betterment of Higher Education. The onset of the Covid 19 pandemic brought a test for the pre... Zambia like any other country in most African regions is still grappling with the dynamics of harnessing technology for the betterment of Higher Education. The onset of the Covid 19 pandemic brought a test for the preparedness of the Zambian Higher Education Institutions (HEIs) in harnessing technology for pedagogical activities. As countries worldwide switched to electronic learning during the pandemic, the same could not be said for Zambian HEIs. Zambian HEIs struggled to conduct pedagogical activities on learning management platforms. This study investigated the factors affecting the implementation and assessment of learning Management systems in Zambia’s HEIs. With its focus on assessing: 1) system features, 2) compliance with regulatory standards, 3) quality of service and 4) technology acceptance as the four key assessment areas of an LMS, this article proposed a model for assessing learning management systems in Zambian HEIs. To test the proposed model, a software tool was also developed. 展开更多
关键词 Learning management systems Assessment Model Technology Acceptance Education Technology
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AI-Driven Learning Management Systems:Modern Developments, Challenges and Future Trends during theAge of ChatGPT
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作者 Sameer Qazi Muhammad Bilal Kadri +4 位作者 Muhammad Naveed Bilal AKhawaja Sohaib Zia Khan Muhammad Mansoor Alam Mazliham Mohd Su’ud 《Computers, Materials & Continua》 SCIE EI 2024年第8期3289-3314,共26页
COVID-19 pandemic restrictions limited all social activities to curtail the spread of the virus.The foremost and most prime sector among those affected were schools,colleges,and universities.The education system of en... COVID-19 pandemic restrictions limited all social activities to curtail the spread of the virus.The foremost and most prime sector among those affected were schools,colleges,and universities.The education system of entire nations had shifted to online education during this time.Many shortcomings of Learning Management Systems(LMSs)were detected to support education in an online mode that spawned the research in Artificial Intelligence(AI)based tools that are being developed by the research community to improve the effectiveness of LMSs.This paper presents a detailed survey of the different enhancements to LMSs,which are led by key advances in the area of AI to enhance the real-time and non-real-time user experience.The AI-based enhancements proposed to the LMSs start from the Application layer and Presentation layer in the form of flipped classroom models for the efficient learning environment and appropriately designed UI/UX for efficient utilization of LMS utilities and resources,including AI-based chatbots.Session layer enhancements are also required,such as AI-based online proctoring and user authentication using Biometrics.These extend to the Transport layer to support real-time and rate adaptive encrypted video transmission for user security/privacy and satisfactory working of AI-algorithms.It also needs the support of the Networking layer for IP-based geolocation features,the Virtual Private Network(VPN)feature,and the support of Software-Defined Networks(SDN)for optimum Quality of Service(QoS).Finally,in addition to these,non-real-time user experience is enhanced by other AI-based enhancements such as Plagiarism detection algorithms and Data Analytics. 展开更多
关键词 Learning management systems chatbots ChatGPT online education Internet of Things(IoT) artificial intelligence(AI) convolutional neural networks natural language processing
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Design and analysis of an advanced thermal management system for the solar close observations and proximity experiments spacecraft
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作者 Liu Liu Kangli Bao +4 位作者 Jianchao Feng Xiaofei Zhu Haoyu Wang Xiaofeng Zhang Jun Lin 《Astronomical Techniques and Instruments》 CSCD 2024年第1期52-61,共10页
In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relat... In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs. 展开更多
关键词 Solar Close Observations and Proximity Experiments Adaptive thermal control method Thermal field planning method Pumped liquid cooling system Advanced thermal management system
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