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An enhanced segmentation method for 3D point cloud of tunnel support system using PointNet++t and coverage-voted strategy algorithms 被引量:1
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作者 Wenju Liu Fuqiang Gao +4 位作者 Shuangyong Dong Xiaoqing Wang Shuwen Cao Wanjie Wang Xiaomin Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1653-1660,共8页
3D laser scanning technology is widely used in underground openings for high-precision,rapid,and nondestructive structural evaluations.Segmenting large 3D point cloud datasets,particularly in coal mine roadways with m... 3D laser scanning technology is widely used in underground openings for high-precision,rapid,and nondestructive structural evaluations.Segmenting large 3D point cloud datasets,particularly in coal mine roadways with multi-scale targets,remains challenging.This paper proposes an enhanced segmentation method integrating improved PointNet++with a coverage-voted strategy.The coverage-voted strategy reduces data while preserving multi-scale target topology.The segmentation is achieved using an enhanced PointNet++algorithm with a normalization preprocessing head,resulting in a 94%accuracy for common supporting components.Ablation experiments show that the preprocessing head and coverage strategies increase segmentation accuracy by 20%and 2%,respectively,and improve Intersection over Union(IoU)for bearing plate segmentation by 58%and 20%.The accuracy of the current pretraining segmentation model may be affected by variations in surface support components,but it can be readily enhanced through re-optimization with additional labeled point cloud data.This proposed method,combined with a previously developed machine learning model that links rock bolt load and the deformation field of its bearing plate,provides a robust technique for simultaneously measuring the load of multiple rock bolts in a single laser scan. 展开更多
关键词 Point cloud segmentation Improved PointNet++ Tunnel laser scanning Rock bolt automatic recognition
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New high-efficiency system for improving oil recovery based on the superwetting phenomenon
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作者 ZHOU Zhaohui ZHANG Xiaojie +5 位作者 ZHANG Qun JIA Ninghong HAN Lu ZHANG Lei ZHANG Lu LYU Weifeng 《Petroleum Exploration and Development》 2025年第5期1301-1313,共13页
Given that a large amount of crude oil remains on the surface of rocks and is difficult to produce after conventional waterflooding,a new superwetting oil displacement system incorporating the synergy between a hydrox... Given that a large amount of crude oil remains on the surface of rocks and is difficult to produce after conventional waterflooding,a new superwetting oil displacement system incorporating the synergy between a hydroxyl anion compound(1OH-1C)and an extended surfactant(S-C_(13)PO_(13)S)was designed.The interfacial tension,contact angle and emulsification performance of the system were measured.The oil displacement effects and improved oil recovery(IOR)mechanisms of 1OH-1C,S-C_(13)PO_(13)S and their compound system were investigated by microscopic visualization oil displacement experiments and core displacement experiments.The results show that 1OH-1C creates a superwetting interface and electrostatic separation pressure on the solid surface,which destroys the strong interactions between crude oil and quartz to peel off the oil film.S-C_(13)PO_(13)S has low interfacial tension,which can promote the flow of remaining oil and emulsify it into oil-in-water emulsions.The compound system of 1OH-1C and S-C_(13)PO_(13)S has both superwettability and low IFT,which can effectively improve oil recovery through a synergistic effect.The oil displacement experiment of low-permeability natural core shows that the compound solution can increase the oil recovery by 16.4 percentage points after waterflooding.This new high-efficiency system is promising for greatly improving oil recovery in low-permeability reservoirs. 展开更多
关键词 superwettability hydroxyl anionic compound extended surfactant SYNERGY oil displacement mechanism chemical flooding improved oil recovery
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Improving MCUCN code to simulate ultracold neutron storage and transportation in superfluid^(4)He
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作者 Xue-Fen Han Fei Shen +6 位作者 Bin Zhou Xiao-Xiao Cai Tian-Cheng Yi Zhi-Liang Hu Song-Lin Wang Tian-Jiao Liang Robert Golub 《Nuclear Science and Techniques》 2026年第3期235-246,共12页
The ultracold neutron(UCN)transport code,MCUCN,designed initially for simulating UCN transportation from a solid deuterium(SD_2)source and neutron electric dipole moment experiments,could not simulate UCN storage and ... The ultracold neutron(UCN)transport code,MCUCN,designed initially for simulating UCN transportation from a solid deuterium(SD_2)source and neutron electric dipole moment experiments,could not simulate UCN storage and transportation in a superfluid^(4)He(SFHe,He-Ⅱ)source accurately.This limitation arose from the absence of an^(4)He upscattering mechanism and the absorption of^(3)He.And the provided source energy distribution in MCUCN is different from that in SFHe source.This study introduced enhancements to MCUCN to address these constraints,explicitly incorporating the^(4)He upscattering effect,the absorption of^(3)He,the loss caused by impurities on converter wall,UCN source energy distribution in SFHe,and the transmission through negative optical potential.Additionally,a Python-based visualization code for intermediate states and results was developed.To validate these enhancements,we systematically compared the simulation results of the Lujan Center Mark3 UCN system by MCUCN and the improved MCUCN code(iMCUCN)with UCNtransport simulations.Additionally,we compared the results of the SUN1 system simulated by MCUCN and iMCUCN with measurement results.The study demonstrates that iMCUCN effectively simulates the storage and transportation of ultracold neutrons in He-Ⅱ. 展开更多
关键词 Ultracold neutron Storage TRANSPORTATION Improved MCUCN code Upscattering effect Absorption by^(3)He
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Transient Voltage Control for AC-DC Hybrid Power System Based on ISAO-CNN-BiGRU
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作者 Xueting Cheng Rui Xu +3 位作者 Liming Bo Cheng Liu Huiping Zheng Zhichong Cao 《Energy Engineering》 2026年第4期214-246,共33页
To address the issue of transient low-voltage instability in AC-DC hybrid power systems following large disturbances,conventional voltage assessment and control strategies typically adopt a sequential“assess-then-act... To address the issue of transient low-voltage instability in AC-DC hybrid power systems following large disturbances,conventional voltage assessment and control strategies typically adopt a sequential“assess-then-act”paradigm,which struggles to simultaneously meet the requirements for both high accuracy and rapid response.This paper proposes a transient voltage assessment and control method based on a hybrid neural network incorporated with an improved snow ablation optimization(ISAO)algorithm.The core innovation of the proposed method lies in constructing an intelligent“physics-informed and neural network-integrated”framework,which achieves the integration of stability assessment and control strategy generation.Firstly,to construct a highly correlated input set,response characteristics reflecting the system’s voltage stable/unstable states are screened.Simultaneously,the transient voltage severity index(TVSI)is introduced as a comprehensive metric to quantify the system’s post-disturbance transient voltage performance.Furthermore,the load bus voltage sensitivity index(LVSI)is defined as the ratio of the voltage change magnitude at a load node(or bus)to the change in the system-level TVSI,thereby pinpointing the response characteristics of critical load nodes.Secondly,both the transient voltage stability assessment result and its corresponding under-voltage load shedding(UVLS)control amount are jointly utilized as the outputs of the response-driven model.Subsequently,the snow ablation optimization(SAO)algorithm is enhanced using a good point set strategy and a Gaussian mutation strategy.This improved algorithm is then employed to optimize the key hyperparameters of the hybrid neural network.Finally,the superiority of the proposed method is validated on a modified CEPRI-36 system and an actual power grid case.Comparisons with various artificial intelligence methods demonstrate its significant advantages in model speed and accuracy.Additionally,when compared to traditional emergency control schemes and UVLS strategies,the proposed method exhibits exceptional rapidness and real-time capability in control decision-making. 展开更多
关键词 Transient voltage stability voltage control AC-DC hybrid power system improved snow ablation optimization hybrid neural network
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From seed to whole plant:An innovative visual marker system to enhance selection efficiency in soybean genome editing
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作者 Tingwei Yan Xueyan Qian +5 位作者 Hong Pan Jiarui Han Qi Wang Chang Liu Dongquan Guo Xiangguo Liu 《Journal of Integrative Agriculture》 2026年第2期820-823,共4页
Emerging and powerful genome editing tools,particularly CRISPR/Cas9,are facilitating functional genomics research and accelerating crop improvement(Jiang et al.2021;Cao et al.2023;Chen C et al.2023;Liu et al.2023a).Ho... Emerging and powerful genome editing tools,particularly CRISPR/Cas9,are facilitating functional genomics research and accelerating crop improvement(Jiang et al.2021;Cao et al.2023;Chen C et al.2023;Liu et al.2023a).However,the detection and screening of transgenic lines remain major bottlenecks,being time-consuming,labor-intensive,and inefficient during transformation and subsequent mutation identification.A simple and efficient visual marker system plays a critical role in addressing these challenges.Recent studies demonstrated that the GmW1 and RUBY reporter systems were used to obtain visual transgenic soybean(Glycine max) plants(Chen L et al.2023;Chen et al.2024). 展开更多
关键词 accelerating crop improvement jiang mutation identificationa enhance selection efficiency SEED functional genomics research detection screening transgenic lines genome editing toolsparticularly innovative visual marker system
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A Systematic Review of Respiratory Monitoring and Assistance Techniques From a Pulmonary Rehabilitation Robot Perspective
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作者 Enming Shi Bi Zhang +7 位作者 Xiaowei Tan Yangfan Zhou Benyan Huo Liping Huang Long Cheng Honghai Liu Lianqing Liu Xingang Zhao 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期259-280,共22页
Pulmonary rehabilitation(PR)aims to improve lung function in patients with chronic respiratory disease(CRD).In recent years,significant advancements have been made in pulmonary rehabilitation technologies,demonstratin... Pulmonary rehabilitation(PR)aims to improve lung function in patients with chronic respiratory disease(CRD).In recent years,significant advancements have been made in pulmonary rehabilitation technologies,demonstrating their potential for enhancing lung function in patients with respiratory diseases.The purpose of this study is to outline recent developments in the field of pulmonary rehabilitation guided by pulmonary rehabilitation robots,which has not been previously addressed in earlier reviews.To fill this gap,this paper first provides a systematic summary of the monitoring and actuation technologies of pulmonary rehabilitation robot systems and evaluates these technologies from multiple dimensions,including portability,wearability potential,invasiveness,and clinical applications,analyzing the potential for integrating various technologies into pulmonary rehabilitation robot systems.Furthermore,three technical directions are proposed:real-time precise monitoring,suitable structure and actuation strategies,and the intelligence of pulmonary rehabilitation robot systems.On the basis of these directions,this paper presents a comprehensive technical outlook for a soft wearable pulmonary rehabilitation robot system,providing reference and guidance for future research.To our knowledge,this is the first review of pulmonary rehabilitation robot systems and their key technologies.Additionally,the review section on respiratory assistive technologies simultaneously covers key technologies such as mechanical ventilation(MV),exoskeleton robots,and functional electrical stimulation(FES)for the first time.It also summarizes the respiratory assistive technology paradigm from the innovative perspectives of respiratory assistive modalities,targeted body sites,and types of ventilation for the first time.This study offers a broader perspective and a deeper understanding of pulmonary re-habilitation robots,with a technical outlook encompassing multimodal data fusion perception,respiratory event detection and intention recognition,full-phase assistance strategies,modeling,decoupling,and quantification of multipleinput multiple-output(MIMO)systems,as well as model-based interactive control strategies. 展开更多
关键词 pulmonary rehabilitation robotswhich improve lung function chronic respiratory disease crd respiratory monitoring pulmonary rehabilitation pr aims pulmonary rehabilitation outline recent developments enhancing lung function
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An automated dispensing system for improving medication timing in the emergency department 被引量:6
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作者 Michael J.Ward Jeremy S.Boyd +7 位作者 Nicole J.Harger John M.Deledda Carol L.Smith Susan M.Walker Jeffrey D.Hice Kimberly W.Hart Christopher J.Lindsell Stewart W.Wright 《World Journal of Emergency Medicine》 CAS 2012年第2期102-107,共6页
BACKGROUND:Numerous medical conditions require timely medication administration in the emergency department(ED).Automated dispensing systems(ADSs)store premixed common doses at the point-of-care to minimize time to ad... BACKGROUND:Numerous medical conditions require timely medication administration in the emergency department(ED).Automated dispensing systems(ADSs)store premixed common doses at the point-of-care to minimize time to administration,but the use of such automation to improved time to medication administration has not been studied.Since vancomycin is a commonly used empiric antimicrobial,we sought to quantify the effect of using an ADS on time to drug delivery in patients presenting to the ED.The study aimed to determine the efficacy of utilizing an ADS to improve time to administration of vancomycin and determine any negative effects on dosing appropriateness.METHODS:The institional review board approved the retrospective quality improvement study took place in a single,urban academic tertiary care ED with an annual census of 80 000.Study subjects were all patients receiving vancomycin for the management of sepsis between March 1 to September 30,2008 and the same time period in 2009.The primary outcome was the proportion of patients who received vancomycin within one hour of bed placement and the secondary outcome was dosing appropriateness.RESULTS:Sixty-three patients had weight and dosing information available(29 before and 34after intervention)and were included in the study.Before intervention,no patient received vancomycin in less than 60 minutes,while after intervention 14.7%of the patients received it in less than 60minutes(difference in proportions 14.7%,95%CI 0.39%-30.0%,P=0.04).A similar proportion of the patients received correct dosing before and after intervention(44.8%vs.41.2%,difference in proportions 3.7%,95%CI-20.0%-26.7%,P=0.770).CONCLUSION:The use of an ADS may improve the timing of medication administration in patients presenting to the ED without affecting dosing appropriateness. 展开更多
关键词 Automatic dispensing system PHARMACEUTICAL Process improvement Efficiency
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Combined imbibition system with black nanosheet and low-salinity water for improving oil recovery in tight sandstone reservoirs 被引量:1
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作者 Dao-Yi Zhu Yu-Heng Zhao +7 位作者 Hong-Jun Zhang Qi Zhao Chen-Yang Shi Jun-Hui Qin Zheng-Hao Su Gui-Qi Wang Yang Liu Ji-Rui Hou 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1562-1571,共10页
Nanomaterials and low-salinity water(LSW)are two popular enhanced oil recovery(EOR)methods that have been widely studied in recent years.The former is used for in-depth conformance improvement and the latter for micro... Nanomaterials and low-salinity water(LSW)are two popular enhanced oil recovery(EOR)methods that have been widely studied in recent years.The former is used for in-depth conformance improvement and the latter for microscopic oil displacement(by altering the potential and contact angle).However,there are few literature on combining them to achieve synergistic effects,especially for tight sandstone res-ervoirs.Based on the reservoir conditions of the Jimusar Oilfield,this study investigated the oil recovery mechanism of the combined imbibition system,which was composed of black nanosheet(BN)and LSW.Its performances including decreasing interfacial tension,emulsification,and wettability alterations were evaluated.The imbibition differences between the single system of BN and LSW and the combined BN-LsW imbibition system were then compared.Results showed that the combined imbibition system had a better emulsification effect on the crude oil and could also alter the wettability of the core surface.Moreover,the combined system could increase both the imbibition rate and the ultimate oil recovery.The nuclear magnetic T2 spectrum also indicated that the addition of black nanosheets could divert more fluid into small pores and thus improve the microscopic sweep efficiency. 展开更多
关键词 Low-salinity water Black nanosheet Combined imbibition system Wettability alteration Improved oil recovery
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Heuristics for Improving Operational Performance of Permutation Circulati on-type Vehicle Routing System
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作者 Hiroshi KISE Mingzhe LU +1 位作者 Guiyan HU Tan LI 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期197-199,共3页
This paper discusses an optimization of operating a p ermutation circulation-type vehicle routing system (PCVRS, for short), in w hich several stages are located along by a single loop, and a fleet of vehicles travels... This paper discusses an optimization of operating a p ermutation circulation-type vehicle routing system (PCVRS, for short), in w hich several stages are located along by a single loop, and a fleet of vehicles travels on the loop unidirectionally and repeatedly. Traveling on the loop, each vehicle receives an object from the loading stage and then carries it to a cert ain processing stage, or receives an object from a certain processing stage and then carries it to the unloading stage per a turnaround. No passing is allowed f or the vehicles on the loop (from which the system is called permutation, and th is restriction may cause interferences between vehicles). Material handling systems such as PCVRS are actually encountered in flexible man ufacturing systems and in automated storage/retrieval systems. In this paper, we propose a heuristic algorithm for operating the PCVRS, which i ncorporates a new scheduling method for the vehicles with the SPT (shortest proc essing time) numbering of jobs and a round-robin manner of allocating jobs to t he stages, aiming to reduce interferences between the vehicles. We also give num erical results with respect to system performances attained by the heuristic. Description of the system The PCVRS consists of a set of n v vehicles V={V 1,V 2,...,V n v}, a set of n s, processing stages S p={S 1,S 2,...,S n s}, a loading stage S 0 and an unloading stage S n s +1. We denote by S=S p∪{S 0,S n s+l} the set of all the stages. The vehicles travel on a single loop unidirectionany and repeated ly. The system layout is depicted in Fig.1. There is a set of n jobs J={J 1,J 2,...,J n} to be processed b y the vehicles. Each job consists of two tasks: That is, each vehicle receives a n object from S 0 and then carries it to S l with a certain l∈{1,2, ...,n s} (a throw-in job), or receives an object from S l with a certain l∈{1,2,...,n s} and then carries it to S n s+1 (a throw-out job ) per a turnaround. The loop consists of buffer zones BZ(l) and travel zones TZ(l) (see Fig. 1). Each buffer zone BZ(l) is placed in front of stage S l, l=0,1,..., n s, n s+1, in order to avoid a collision between vehicles (i.e., the syste m adopts the so-called zone control strategy). A heuristic algorithm We develop a heuristic algorithm to obtain a good performance for the PCVRS. An operation π={A/B/C} for the PCVRS consists of three decision factors: (A) Numbering jobs Jobs are loaded into S 0 according to an assending order of job numbers. In this paper, we use the following rules to number jobs: SPT: Order jobs in the shortest processing time rule, i.e., P 1≤P 2≤...≤P n for the set of jobs J={J 1,J 2,...,J n}, rather than the FCFS numbering (i.e., number jobs in first-come-first-served order). The SPT rule intends to reduce interferences between two adjacent vehicles at stages. (B) Allocating jobs to stages For the purpose of balancing loads of processing stages, we adopt the following to allocate jobs to the stages: ORDER: Allocate n jobs to n s, processing stages by an in-order manner , i.e., let l(i) be the index of processing stage allocated job J i by ORDER, it holds that l(i)=n s+1-(i-[(i-1)/n s]n s).(1) The ORDER rule intends to process jobs parallel at stages as many as possible. (C) Scheduling vehicles The following method for scheduling vehicles under ORDER rule is already known: Fig.1 The vehicle ro uting system, PCVRS Fig.2 Mean turnaroun d times by heuristics Unchange: Assign n jobs to n v vehicles such that let k(i) be the i ndex of vehicle processing job J i, then k(i)= i-[(i-1)/n v]n v.(2) In csse of n v≥n s, mod (n v,n s)=0 or n v<n s, mod (n s,n v)=0 (mod(x,y) is the remainder of x/y), the number of interferences between vehicles is minimized at stage S 1 under Unchange sche dules, while in the other cases it is not [Lu et al. (2001a)]. Therefore, in t his paper, we develop a new scheduling method of the vehicles, denoted by Ex change, to modify Unchange schedules. Note 展开更多
关键词 Heuristics for improving Operational Performance of Permutation Circulati on-type Vehicle Routing system type
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Improving the efficiency of transport systems using simulation
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作者 Bushuev Sergey Valentinovich Kovalev Igor Alexandrovich +1 位作者 Permikin Vadim Yurievich Anashkina Nataliia Yurievna 《系统仿真学报》 CAS CSCD 北大核心 2020年第2期340-345,共6页
The article describes the possibilities of application of simulation modeling for the analysis of infrastructure and technology of transport services of enterprises. The main technological and possible economic effect... The article describes the possibilities of application of simulation modeling for the analysis of infrastructure and technology of transport services of enterprises. The main technological and possible economic effects for the enterprises arising at performance of modeling of a transport component of their work are resulted. 展开更多
关键词 SERVICE improving the efficiency of transport systems using simulation
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Restraining Factors and Improving Paths for the Operation Mechanism of New Rural Cooperative Medical System in China
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作者 QI Bin TANG Xia 《Asian Agricultural Research》 2011年第2期105-108,115,共5页
The new rural cooperative medical system has achieved periodical achievements since its establishment.Nevertheless,there are many factors hampering the development of the new system,such as the high cost,the difficult... The new rural cooperative medical system has achieved periodical achievements since its establishment.Nevertheless,there are many factors hampering the development of the new system,such as the high cost,the difficulties in fund procurement,the lack of management,the narrow coverage of benefit,the ineffective constraint to the designated medical institutions,the high fund balance rate,and the poor medical facilities and services in rural areas.Countermeasures are put forward to solve these problems,including improving the system design,expanding the coverage of the system,expanding the fund sources,reducing the financing costs,strengthening the fund supervision,enhancing the supervision of designated medical institutions,and improving the capacity of health services in rural areas. 展开更多
关键词 New rural cooperative medical system Restraining factors improving paths China
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Qualitative Comparison between the Brazilian Labeling Program for Buildings and the Portuguese Energy Certification System for Buildings:Proposals for Improving Brazilian Regulations
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作者 Jaime Francisco de Sousa Resende Andrea Lucia Teixeira Charbel Teresa Cristina Bessa Nogueira Assunção 《Energy Engineering》 EI 2021年第3期615-629,共15页
Buildings represent a significant share of the world’s energy consumption,and the sector has drawn the attention of governments,which have adopted policies to reduce energy expenditure.The Certifications of Energy Ef... Buildings represent a significant share of the world’s energy consumption,and the sector has drawn the attention of governments,which have adopted policies to reduce energy expenditure.The Certifications of Energy Efficiency in Buildings stand out as one possible solution to achieve this goal,employed in several countries worldwide.The European Union presents advanced energy assessment programs for buildings,being a reference and model for several other regulations in the world.The Energy Certification System for Buildings(SCE)of Portugal is considered a success case,reflected in the significant number of energy certificates issued.The Brazilian Labeling Program for Building(PBE Edifica),first launched in 2009,does not find a broad application today in the Brazilian scenario.This work shows a synthesis of the European Energy Performance of Buildings Directive(EPBD)and the Brazilian and Portuguese regulations’history.A qualitative comparison is made between the SCE and the PBE Edifica to verify a European and a developing country’s regulations with a certain degree of cultural and climatic similarities.Through this comparison,proposals are made for improvements to Brazilian certification,seeking to improve its energy planning and energy policy concerning its building stock.The suggestions for improvement presented may also be appropriate for other developing countries that have started and have not yet successfully implemented their energy certification programs in buildings. 展开更多
关键词 Energy efficiency energy policy building labeling energy certification improvement proposals
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Research on the Effective Ways of Improving the Teaching System of Physical Education Theory in Universities
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作者 Yuebiao Sang Rong Li 《Journal of Sports Science》 2017年第5期285-288,共4页
Through the methods of literature and on-the-spot visit, this paper aims at studying the teaching system of physical education theory and the innovation of teaching methods in colleges and universities, and promoting ... Through the methods of literature and on-the-spot visit, this paper aims at studying the teaching system of physical education theory and the innovation of teaching methods in colleges and universities, and promoting the perfection of the teaching system of physical education (PE) theory in universities. 展开更多
关键词 College PE theoretical teaching method improvement.
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Strenghthening Understanding Improving Cooperation and Promoting Development──Highlights on the Seminar “Social Security Systems in Asian Countries,a Comparison of Problems and Perspectives”
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《International Understanding》 1994年第2期12-,14,共2页
StrenghtheningUnderstandingImprovingCooperationandPromotingDevelopment──HighlightsontheSeminar“SocialSecurit... StrenghtheningUnderstandingImprovingCooperationandPromotingDevelopment──HighlightsontheSeminar“SocialSecuritySystemsinAsianCo... 展开更多
关键词 SEMINAR COOPERATION ASIAN COUNTRIES Development HIGHLIGHTS improving PERSPECTIVES Problems Promoting
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Improving Performance of Computer Algebra Systems
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作者 Kostas Zotos Irena Atanassova 《Journal of Software Engineering and Applications》 2023年第10期521-529,共9页
Computer Algebra Systems have been extensively used in higher education. The reasons are many e.g., visualize mathematical problems, correlate real-world problems on a conceptual level, are flexible, simple to use, ac... Computer Algebra Systems have been extensively used in higher education. The reasons are many e.g., visualize mathematical problems, correlate real-world problems on a conceptual level, are flexible, simple to use, accessible from anywhere, etc. However, there is still room for improvement. Computer algebra system (CAS) optimization is the set of best practices and techniques to keep the CAS running optimally. Best practices are related to how to carry out a mathematical task or configure your system. In this paper, we are going to examine these techniques. The documentation sheets of CASs are the source of data that we used to compare them and examine their characteristics. The research results reveal that there are many tips that we can follow to accelerate performance. 展开更多
关键词 Mathematical Software Computer Algebra systems CAS improving Performance CAS Performance CAS Optimization MATLAB MAPLE MATHEMATICA
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Parameter matching and optimization of hybrid excavator swing system 被引量:1
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作者 Chao SHEN Jianxin ZHU +2 位作者 Jian CHEN Saibai LI Lixin YI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第2期138-150,共13页
In this study,a novel synergistic swing energy-regenerative hybrid system(SSEHS)for excavators with a large inertia slewing platform is constructed.With the SSEHS,the pressure boosting and output energy synergy of mul... In this study,a novel synergistic swing energy-regenerative hybrid system(SSEHS)for excavators with a large inertia slewing platform is constructed.With the SSEHS,the pressure boosting and output energy synergy of multiple energy sources can be realized,while the swing braking energy can be recovered and used by means of hydraulic energy.Additionally,considering the system constraints and comprehensive optimization conditions of energy efficiency and dynamic characteristics,an improved multi-objective particle swarm optimization(IMOPSO)combined with an adaptive grid is proposed for parameter optimization of the SSEHS.Meanwhile,a parameter rule-based control strategy is designed,which can switch to a reasonable working mode according to the real-time state.Finally,a physical prototype of a 50-t excavator and its AMESim model is established.The semi-simulation and semi-experiment results demonstrate that compared with a conventional swing system,energy consumption under the 90°rotation condition could be reduced by about 51.4%in the SSEHS before parameter optimization,while the energy-saving efficiency is improved by another 13.2%after parameter optimization.This confirms the effectiveness of the SSEHS and the IMOPSO parameter optimization method proposed in this paper.The IMOPSO algorithm is universal and can be used for parameter matching and optimization of hybrid power systems. 展开更多
关键词 Hybrid system Energy regeneration Swing braking energy Parameter optimization Improved multi-objective particle swarm optimization(IMOPSO) Adaptive grid
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Strategies for Improving the Standard System of Tropical Crop Machinery
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作者 By Huang Hui ang wang jinli Agricultural Machinery Re-search Institute of Chinese Academy of Tropical A-gricultural Sciences Test Center of Quality Supervi-sion and Test for Tropical Crop Machinery Depart-ment of Agriculture 《China Standardization》 2004年第6期30-33,共4页
关键词 Strategies for improving the Standard system of Tropical Crop Machinery
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An Improved Repetitive-Control System Using a Complex-Coefficient Filter 被引量:1
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作者 Qicheng Mei Jinhua She +1 位作者 Fei Long Yanjun Shen 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期282-284,共3页
Dear Editor,This letter presents an improved repetitive controller(IRC) that uses a complex-coefficient filter to enhance the tracking performance of a system for periodic signals. Compared with the low-pass filter us... Dear Editor,This letter presents an improved repetitive controller(IRC) that uses a complex-coefficient filter to enhance the tracking performance of a system for periodic signals. Compared with the low-pass filter used in the conventional repetitive controller(CRC), the complex-coefficient filter causes less change in the phase and amplitude of a signal at the frequencies of the periodic signal, especially at the fundamental frequency, when the two filters have the same cutofffrequency. 展开更多
关键词 improved repetitive controller irc periodic signals repetitive control system complex coefficient filter tracking performance conventional repetitive controller crc periodic signal enhance tracking performance
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Discussion on the Construction of Management and Control System for Improving Quality Reducing Cost and Increasing Efficiency of Thermal Power Generation Enterprises
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作者 LIU Ruiping 《外文科技期刊数据库(文摘版)经济管理》 2021年第1期016-020,共5页
The management and control system of improving quality, reducing cost and increasing efficiency aims to establish a corresponding incentive target system around the business tasks and development goals of the enterpri... The management and control system of improving quality, reducing cost and increasing efficiency aims to establish a corresponding incentive target system around the business tasks and development goals of the enterprise, guides the company all units and departments to strengthen the internal management, full of all aspects of mining efficiency potential, enhances the endogenous development of the enterprise power, so as to effectively cope with the market crisis, improve enterprise efficiency. With the end of the "golden decade" of thermal power generation enterprise market, the production and operation of thermal power generation enterprises are increasingly difficult. In order to effectively deal with the power market under the declining price environment, tap the internal efficiency potential of enterprises, and realize the loss and gain. Combined with the characteristics and actual situation of the enterprise, on the basis of summarizing previous experience, focusing on the high-quality development of the enterprise, highlighting value creation, making up for shortcomings, promoting reform and increasing benefits, the paper proposes to construct a management and control system to improve quality, reduce cost and increase efficiency. 展开更多
关键词 thermal power generation quality improvement and cost reduction CONTROL CONSTRUCTION
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Efficacy of dynamic interpersonal therapy in improving mentalising in patients with major depressive disorder and the mediating effect of mentalising on changes in depressive symptoms
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作者 Wenhui Jiang Jiayu Yao +4 位作者 Yuan Wang Shanshan Su Ziwei Zheng Yang Yang Jianyin Qiu 《General Psychiatry》 2025年第1期16-25,共10页
Background Dynamic interpersonal therapy(DIT)is a short-term psychodynamic psychotherapy that has been shown to effectively reduce depressive symptoms in patients with major depressive disorder(MDD).In DIT,the depress... Background Dynamic interpersonal therapy(DIT)is a short-term psychodynamic psychotherapy that has been shown to effectively reduce depressive symptoms in patients with major depressive disorder(MDD).In DIT,the depressive symptoms are formulated as responses to impaired mentalisation.DIT aims to alleviate depressive symptoms by improving mentalising.Aims This study aimed to examine the effect of DIT on improving mentalising and the mediating effect of mentalising in changes in depressive symptoms.Methods Outpatients received either DIT combined with antidepressant medication treatment(DIT group)or antidepressant medication treatment alone(ADM group)for 16 weeks.The Hamilton Depression Rating Scale(HAMD),Patient Health Questionnaire(PHQ)and Reflective Functioning Questionnaire(RFQ)were used.The intention-to-treat principle,mixed linear models,multiple imputation,Pearson's correlation analysis and mediation analysis were conducted.The per-protocol principle was used as sensitivity analysis.Results The DIT group had significantly lower HAMD(least-squares(LS)mean difference=-3.756,p<0.001),PHQ(LS mean difference=-4.188,p<0.001),uncertainty about mental states in the RFQ(RFQ-U,LS mean difference=-2.116,p<0.001)and higher certainty about mental states in the RFQ(RFQ-C,LS mean difference=2.214,p=0.028)scores than the ADM group at post-treatment.The change in RFQ-C was marginally significantly correlated with the change in HAMD(r=-0.218,poretao=0.090),The change in RFQ-U was significantly correlated with the change in HAMD(r=-0.269,poroco-0.024)and the change in PHQ(r=-0.43,Peoretceo l<e0.001).When using RFQ-U as the mediating variable and PHQ as the dependent variable,a significant mediating effect was found(p=0.043,95% confidence interval 0.024 to 1.453).Conclusions The DIT group yielded better outcomes compared with the ADM group in reducing depressive symptoms and improving mentalising.Improvements in mentalising were associated with reductions in depressive symptoms.These findings support that mentalising may contribute to the therapeutic effects of DIT in MDD. 展开更多
关键词 alleviate depressive symptoms Mentalising dynamic interpersonal therapy dit improving mentalising improving mentalisingaims reduce depressive symptoms psychodynamic psychotherapy depressive symptoms
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