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Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge
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作者 Xilong Zheng Qiong Wang Di Guan 《Structural Durability & Health Monitoring》 EI 2024年第3期361-376,共16页
The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation ... The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively. 展开更多
关键词 Continuous rigid frame bridge REHABILITATION long-term monitoring field load test safety standard determination
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Standard Framework Construction of Technology and Equipment for Big Data in Crop Phenomics
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作者 Weiliang Wen Shenghao Gu +2 位作者 Ying Zhang Wanneng Yang Xinyu Guo 《Engineering》 SCIE EI CAS CSCD 2024年第11期175-184,共10页
Crop phenomics has rapidly progressed in recent years due to the growing need for crop functional geno-mics,digital breeding,and smart cultivation.Despite this advancement,the lack of standards for the cre-ation and u... Crop phenomics has rapidly progressed in recent years due to the growing need for crop functional geno-mics,digital breeding,and smart cultivation.Despite this advancement,the lack of standards for the cre-ation and usage of crop phenomics technology and equipment has become a bottleneck,limiting the industry’s high-quality development.This paper begins with an overview of the crop phenotyping indus-try and presents an industrial mapping of technology and equipment for big data in crop phenomics.It analyzes the necessity and current state of constructing a standard framework for crop phenotyping.Furthermore,this paper proposes the intended organizational structure and goals of the standard frame-work.It details the essentials of the standard framework in the research and development of hardware and equipment,data acquisition,and the storage and management of crop phenotyping data.Finally,it discusses promoting the construction and evaluation of the standard framework,aiming to provide ideas for developing a high-quality standard framework for crop phenotyping. 展开更多
关键词 Crop phenomics Big data Phenotyping technology and equipment standard framework Industrial mapping
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Study on Designing Standards System Framework of Hainan National Breeding and Multiplication
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作者 陈冠铭 杨静 +2 位作者 林亚琼 汪李平 李劲松 《Agricultural Science & Technology》 CAS 2012年第7期1437-1442,共6页
A preliminary feasibility study was set up for the HNBM standard system. By introducing the set theory and basic methods of the solid geometry and adopting the Verman three-dimensional structure ideology innovatively,... A preliminary feasibility study was set up for the HNBM standard system. By introducing the set theory and basic methods of the solid geometry and adopting the Verman three-dimensional structure ideology innovatively, the standards system of Hainan National Breeding and Multiplication (HNBM) was studied with the four-dimensional structure and integration by combining with the time dimension. The four-dimensional structure standards system will be useful for guiding the construction of the HNBM standards system, carrying on the division of labor and realizing the dynamic development of the standards system. The standards set of HNBM helps to computer programming and information management. 展开更多
关键词 Hainan National Breeding and Multiplication Four-dimensional standards system ASSEMBLING Dynamic system stardards set
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Study on establishment of standardized load spectrum on bogie frames of high-speed trains 被引量:4
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作者 Daoyun Chen Qian Xiao +2 位作者 Minghui Mou Shouguang Sun Qiang Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第4期812-827,共16页
Establishing structural load spectrum under actual operating conditions is a major problem in structural fatigue life analysis. This study introduces the load measuring method for the bogie frame structure. The load-m... Establishing structural load spectrum under actual operating conditions is a major problem in structural fatigue life analysis. This study introduces the load measuring method for the bogie frame structure. The load-measuring frame based on quasi-static can measure different load systems synchronously. The t-test method is employed to evaluate the least test time of deducing the parent distribution. In order to fit the load spectrum distribution accurately, the kernel density estimation method is employed which is based on the sample characteristics. The expansion factor method is used to deduce the maximum load. The formula of standardized load spectrum derives from the deduced maximum load, the linear factor between operating condition length and cumulative frequency and the parent distribution of each load system. The damage consistency criterion is performed by solving the objective function with constraint conditions. The calibrated damage provides a suitable representation of the real damage under actual operating conditions. By processing and analyzing the load spectrum and stress spectrum data of the measured lines, it is verified that the standardized load spectrum established in this paper is superior to the European specification and the Japanese specification in evaluating the fatigue reliability of the structure. 展开更多
关键词 Load SPECTRUM BOGIE frame KERNEL density EXPANSION factor Damage calibration
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The Arithmetic Mean Standard Deviation Distribution: A Geometrical Framework 被引量:1
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作者 R. Caimmi 《Applied Mathematics》 2013年第11期1-10,共10页
The current attempt is aimed to outline the geometrical framework of a well known statistical problem, concerning the explicit expression of the arithmetic mean standard deviation distribution. To this respect, after ... The current attempt is aimed to outline the geometrical framework of a well known statistical problem, concerning the explicit expression of the arithmetic mean standard deviation distribution. To this respect, after a short exposition, three steps are performed as 1) formulation of the arithmetic mean standard deviation, , as a function of the errors, , which, by themselves, are statistically independent;2) formulation of the arithmetic mean standard deviation distribution, , as a function of the errors,;3) formulation of the arithmetic mean standard deviation distribution, , as a function of the arithmetic mean standard deviation, , and the arithmetic mean rms error, . The integration domain can be expressed in canonical form after a change of reference frame in the n-space, which is recognized as an infinitely thin n-cylindrical corona where the symmetry axis coincides with a coordinate axis. Finally, the solution is presented and a number of (well known) related parameters are inferred for sake of completeness. 展开更多
关键词 standard Deviation n-Spaces Direction Cosines QUADRICS
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Standardization Framework of Marine Sustainable Development Evaluation System 被引量:1
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作者 Ye Shenglin,Ma Chun and Ju Meiting 《China Standardization》 2009年第6期16-20,共5页
The core concepts of standardization framework of marine sustainable development evaluation systemare fairness and justice and the aim of sustainable development is to pursue development beneficial bothfor the current... The core concepts of standardization framework of marine sustainable development evaluation systemare fairness and justice and the aim of sustainable development is to pursue development beneficial bothfor the current and future generations.Scientific evaluation of sustainable marine development is importantfor ensuring an accurate level of marine development.Establishing a scientific evaluation system is of greatimportance in the planning of marine development.Standardization of such an evaluation system needs tobe based on comprehensive work and must be founded on both marine science and modern managementprinciples.This paper analyses the current marine standards situation and looks at the assessment systemfor marine sustainable development.It also lists the main reasons for the standardization of a sustainablemarine development evaluation system and analyses five existing marine standardization problems whichare a constraint to this standardization.Finally a framework of marine sustainable development evaluationsystem standardization is established.The conclusion incorporates some advice on how to promote thisstandardization. 展开更多
关键词 standardIZATION marine sustainable development evaluation system
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A Study on Framework of Open Standard and Intellectual Property in E-Business
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作者 Bi Chunli Shu Huaying Xi Jiarong 《China Communications》 SCIE CSCD 2007年第4期89-93,共5页
With the progress and development of information society,electronic business(e-Business) becomes a new model of business.E-Business does lower the cost of trading significantly;furthermore it allows restructuring the ... With the progress and development of information society,electronic business(e-Business) becomes a new model of business.E-Business does lower the cost of trading significantly;furthermore it allows restructuring the supply chain,business processes, and the nature of business.Open standard plays an important role in expanding e-Business,ranging from the Internet protocol(TCP/IP,HTTP...) to nearly all aspects of information technology that related to e-Business.More importantly,openness has emerged as a strategy with many of the most successful e-Business ventures granting business partner and consumers unparallel access to their inner working and personnel.Open standards have given rise to a prodigious international expansion in the number of users and range of applications relevant to daily life.The traditional market failure argument suggests that because innovation is expensive to produce and cheap to copy,so more intellectual property incorporated into the standards,and e-Business is inevitable.This paper defines the new framework of e-Business,which describes the relationship of the public benefit from Open Standard and the private benefit from intellectual property and try to find a balance between the benefits of the patent holders,industry,and end-users in order to realize a winning situation for all parties. 展开更多
关键词 IPR E-BUSINESS OPEN standard
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Dynamic interactive bitwise meta-holography with ultra-high computational and display frame rates 被引量:2
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作者 Yuncheng Liu Ke Xu +4 位作者 Xuhao Fan Xinger Wang Xuan Yu Wei Xiong Hui Gao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期36-46,共11页
Interactive holography offers unmatched levels of immersion and user engagement in the field of future display.Despite of the substantial progress has been made in dynamic meta-holography,the realization of real-time,... Interactive holography offers unmatched levels of immersion and user engagement in the field of future display.Despite of the substantial progress has been made in dynamic meta-holography,the realization of real-time,highly smooth interactive holography remains a significant challenge due to the computational and display frame rate limitations.In this study,we introduced a dynamic interactive bitwise meta-holography with ultra-high computational and display frame rates.To our knowledge,this is the first reported practical dynamic interactive metasurface holographic system.We spa-tially divided the metasurface device into multiple distinct channels,each projecting a reconstructed sub-pattern.The switching states of these channels were mapped to bitwise operations on a set of bit values,which avoids complex holo-gram computations,enabling an ultra-high computational frame rate.Our approach achieves a computational frame rate of 800 kHz and a display frame rate of 23 kHz on a low-power Raspberry Pi computational platform.According to this methodology,we demonstrated an interactive dynamic holographic Tetris game system that allows interactive gameplay,color display,and on-the-fly hologram creation.Our technology presents an inspiration for advanced dynamic meta-holography,which is promising for a broad range of applications including advanced human-computer interaction,real-time 3D visualization,and next-generation virtual and augmented reality systems. 展开更多
关键词 interactive display meta-holography bitwise operation ultra-high frame rate
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Development of a new cerebral ischemia reperfusion model of Mongolian gerbils and standardized evaluation system 被引量:3
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作者 Ying Wu Caijiao Hu +9 位作者 Zhihui Li Feiyang Li Jianyi Lv Meng Guo Xin Liu Changlong Li Xueyun Huo Zhenwen Chen Lifeng Yang Xiaoyan Du 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第1期48-55,共8页
Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symp... Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symptoms are caused by numerous complex variant types of the circle.Additionally,the lack of an evaluation system for the cer-ebral ischemia/reperfusion(I/R)model of gerbils has shackled the application of this model.Methods:We created a symptom-oriented principle and detailed neurobehavioral scoring criteria.At different time points of reperfusion,we analyzed the alteration in locomotion by rotarod test and grip force score,infarct volume by triphenyltetrazo-lium chloride(TTC)staining,neuron loss using Nissl staining,and histological charac-teristics using hematoxylin-eosin(H&E)straining.Results:With a successful model rate of 56%,32 of the 57 gerbils operated by our method harbored typical features of cerebral I/R injury,and the mortality rate in the male gerbils was significantly higher than that in the female gerbils.The suc-cessfully prepared I/R gerbils demonstrated a significant reduction in motility and grip strength at 1 day after reperfusion;formed obvious infarction;exhibited typi-cal pathological features,such as tissue edema,neuronal atrophy and death,and vacuolated structures;and were partially recovered with the extension of reperfu-sion time.Conclusion:This study developed a new method for the unilateral common carotid artery ligation I/R model of gerbil and established a standardized evaluation system for this model,which could provide a new cerebral I/R model of gerbils with more practical applications. 展开更多
关键词 ISCHEMIA/REPERFUSION Mongolian gerbil standardized model system unilateral carotid occlusion
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The Weighted Mean Standard Deviation Distribution: A Geometrical Framework
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作者 R. Caimmi 《Applied Mathematics》 2015年第3期520-546,共27页
The current attempt is aimed to extend previous results, concerning the explicit expression of the arithmetic mean standard deviation distribution, to the general case of the weighted mean standard deviation distribut... The current attempt is aimed to extend previous results, concerning the explicit expression of the arithmetic mean standard deviation distribution, to the general case of the weighted mean standard deviation distribution. To this respect, the integration domain is expressed in canonical form after a change of reference frame in the n-space, which is recognized as an infinitely thin n-cylindrical corona where the axis coincides with a coordinate axis and the orthogonal section is an infinitely thin, homotetic (n-1)-elliptical corona. The semiaxes are formulated in two different ways, namely in terms of (1) eigenvalues, via the eigenvalue equation, and (2) leading principal minors of the matrix of a quadratic form, via the Jacobi formulae. The distribution and related parameters have the same formal expression with respect to their counterparts in the special case where the weighted mean coincides with the arithmetic mean. The reduction of some results to ordinary geometry is also considered. 展开更多
关键词 standard Deviation n-Spaces Direction Cosines QUADRATIC FORMS MATRIX Theory
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Cascaded ELM-Based Joint Frame Synchronization and Channel Estimation over Rician Fading Channel with Hardware Imperfections 被引量:1
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作者 Qing Chaojin Rao Chuangui +2 位作者 Yang Na Tang Shuhai Wang Jiafan 《China Communications》 SCIE CSCD 2024年第6期87-102,共16页
Due to the interdependency of frame synchronization(FS)and channel estimation(CE),joint FS and CE(JFSCE)schemes are proposed to enhance their functionalities and therefore boost the overall performance of wireless com... Due to the interdependency of frame synchronization(FS)and channel estimation(CE),joint FS and CE(JFSCE)schemes are proposed to enhance their functionalities and therefore boost the overall performance of wireless communication systems.Although traditional JFSCE schemes alleviate the influence between FS and CE,they show deficiencies in dealing with hardware imperfection(HI)and deterministic line-of-sight(LOS)path.To tackle this challenge,we proposed a cascaded ELM-based JFSCE to alleviate the influence of HI in the scenario of the Rician fading channel.Specifically,the conventional JFSCE method is first employed to extract the initial features,and thus forms the non-Neural Network(NN)solutions for FS and CE,respectively.Then,the ELMbased networks,named FS-NET and CE-NET,are cascaded to capture the NN solutions of FS and CE.Simulation and analysis results show that,compared with the conventional JFSCE methods,the proposed cascaded ELM-based JFSCE significantly reduces the error probability of FS and the normalized mean square error(NMSE)of CE,even against the impacts of parameter variations. 展开更多
关键词 channel estimation extreme learning machine frame synchronization hardware imperfection nonlinear distortion synchronization metric
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The impact of the Rural Minimum Living Standard Guarantee(Rural Dibao)Program on child nutrition outcomes 被引量:1
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作者 Dian Chen Xiangming Fang +3 位作者 Yu Chen Xiaodong Zheng Zhuo Chen Rodney B.W.Smith 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期444-456,共13页
The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural China.Despite the importance of children’s nutrition in breaking poverty cycle... The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural China.Despite the importance of children’s nutrition in breaking poverty cycles,little is known about the impact of Rural Dibao on child nutrition outcomes.Using China Family Panel Studies(CFPS),this paper examines the effects of Rural Dibao on child nutrition outcomes and investigates potential pathways and heterogeneous effects.We exploit propensity score matching and difference-in-differences techniques to evaluate the effects of the Rural Dibao program on child nutrition outcomes.Our results suggest that Rural Dibao significantly impacts the nutrition outcomes of children up to 15 years of age.Specifically,our results suggest that Rural Dibao improves child height-to-age z-scores by 1.05 standard deviations and lowers the probability of stunting by 11.9 percentage points.Additional analyses suggest that increased protein intake is the main pathway through which Rural Dibao participation contributes to better nutrition outcomes.We also find that the effect of the program is more pronounced among girls,children who are non-left-behind or live with highly educated mothers,and those from low-income families and poor areas.Our findings suggest that Rural Dibao participation helps improve child nutrition outcomes through improving diet quality. 展开更多
关键词 Rural Minimum Living standard Guarantee NUTRITION height-to-age z-scores STUNTING rural China
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Evaluation of the Impact of International Accounting Standards Board (IASB) Framework Concepts on the Public Accounting Profession
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作者 Zivanai Mazhambe 《Journal of Modern Accounting and Auditing》 2014年第3期327-332,共6页
Accounting profession has, in recent times, been regulated mainly by the private accounting standard setters mainly the International Accounting Standards Board (IASB), which has taken a center stage and redefined t... Accounting profession has, in recent times, been regulated mainly by the private accounting standard setters mainly the International Accounting Standards Board (IASB), which has taken a center stage and redefined the accounting information systems beyond the knowledge discernment of the average users and stakeholders. Public accounting profession's overreliance on the ever-changing IASB conceptual frameworks and their subsequent publications International Financial Reporting Standards (IFRS) standards has strongly compromised the ethics and objectivity of the profession, especially the accounting fundamental qualitative characteristics of the fair representation. Public accountants are, by ethics, required to issue an accurate, independent, and objective opinion of the financial state of the reporting entity. A review of various literatures from the IASB and the related bodies including independent auditors was employed during the evaluation process so as to minimize bias and evaluate objectively. The results revealed that currently, the IASB conceptual frameworks and IFRS contain inconsistent and opposing objectives including an inconclusive definition of elements and measurement basis mainly of profit and loss transactions and other comprehensive income, and hence the public accounting profession has been ethically challenged and compromised. Financial reporting is now premised on estimates, judgments, and models as opposed to a definitive measurement in accounting. A recommendation of further study on the IASB fundamental qualitative characteristics of decision usefulness should be pursued objectively. 展开更多
关键词 Intemational Accounting standards Board (IASB) public accounting financial reporting conceptualframeworks
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Review of International Accounting Standards Board (IASB) Proposed New Conceptual Framework: Discussion Paper (DP/2013/1)
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作者 Zivanai Mazhambe 《Journal of Modern Accounting and Auditing》 2014年第8期835-845,共11页
The International Accounting Standards Board (IASB) is one of the largest independent accounting standard setters whose publications, International Financial Reporting Standards (IFRSs), have revolutionalized the ... The International Accounting Standards Board (IASB) is one of the largest independent accounting standard setters whose publications, International Financial Reporting Standards (IFRSs), have revolutionalized the accounting profession, investors, finance providers, and the entire accounting information stakeholder community. The conceptual frameworks are the theoretical accounting bases that are constituted by a set of principles that underlie as a bedrock foundation cornerstone for the development and updating of IFRSs. The existing conceptual frameworks were issued by IASB in 2010, after long years of protracted and wide consultation and joint project with the biggest American standard setter Financial Accounting Standards Board (FASB). In year 2013, the IASB embarked on a solo project to update the conceptual framework and issued a discussion paper (DP/2013/1) to its users and stakeholder community for comments. The methodology used in this study of an extensive review of literature (secondary/primary) from the discussion paper, existing conceptual framework, and comment letters from investors, accounting, insurance, and international audit firms has been manipulated. The findings revealed that the existing conceptual framework has opposing objectives especially that of decision usefulness (future-oriented information) and concepts of "prudence and stewardship/accountability", which are deeply embedded within the framework as subsumed, but their prominence has been overshadowed and watered down by not identifying them as objectives. The finding also revealed that almost all public accounting and audit firms are advocating not only for the reinstatement of the "prudence and stewardship/accountability" but also for a clear definition of recognition, de-recognition, and measurement of statement of financial position elements (assets and liabilities) and also elements of the comprehensive income statement (revenues and expenses), which have seriously compromised investors, public accounting profession, learning/teaching of a framework-based understanding, and the entire IFRS user stakeholder community. A recommendation for further studying the abandoned joint IASB/FASB project should be investigated in the best interest of international accounting standards convergence. 展开更多
关键词 International Accounting standards Board (IASB) discussion paper (DP/2013/1) PRUDENCE STEWARDSHIP conceptual framework
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Performance and Safety Improvement of Induction Motors based on Testing and Evaluation Standards
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作者 Nkosinathi S.Khumalo Ntombizotwa P.Memane Udochukwu B.Akuru 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第3期310-318,共9页
The induction motor,which converts electrical energy into mechanical energy,has been recognized as the cornerstone of industrialization.The rotor of an induction motor can be either a squirrel cage rotor or a wound-ty... The induction motor,which converts electrical energy into mechanical energy,has been recognized as the cornerstone of industrialization.The rotor of an induction motor can be either a squirrel cage rotor or a wound-type rotor,both existing as magnetless topologies.Three-phase squirrel cage induction motors are frequently utilized in industrial drives because they are dependable,have high starting torque,are selfstarting and affordable.Single-phase induction motors,on the other hand,are commonly used for small loads such as domestic appliances in form of modest fans,pumps and electric power tools.In South Africa,there have been reports of fires and explosions resulting in live and property loss because of induction motors that have not been thoroughly tested or are incorrectly labelled in terms of ratings,electrical safety and performance.The goal of this study is targeted at preventing end-user injuries and failures caused by non-compliant induction motors,by evaluating locally manufactured/imported induction motors based on tests and evaluation from standards(IEC and SANS).The study is conducted using experimental procedures at the Explosion Prevention Technology and Rotating Machines(EPT and RM)laboratory,South African Bureau of Standards(SABS),South Africa.The main finding from the study shows differences in the nameplate characteristics of various induction motors which could have detrimental effects such as production and operational downtime in their end-use industries,at later stages. 展开更多
关键词 COMPLIANCE Induction motors International Electro-Technical standards(IEC) NAMEPLATE Experimental tests South African National standards(SANS)
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Defining the We-map Reference Frames and Providing Mathematical Expressions for Transformation Relations
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作者 WANG Xiaolong YAN Haowen +2 位作者 WANG Zhuo MA Wenjun YU Yitao 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第3期76-88,共13页
We-map is an interactive mobile map that can be easily communicated and applied on personal electronic devices,such as personal computers and mobile phones.Therefore,the study of direction systems and coordinate syste... We-map is an interactive mobile map that can be easily communicated and applied on personal electronic devices,such as personal computers and mobile phones.Therefore,the study of direction systems and coordinate systems is critical,and exploring reference frames is essential in direction and coordinate systems.Despite its significance,existing research on We-map lacks specific solutions for the exploration of reference frames is indispensable for the establishment of accurate direction and coordinate systems.In this paper,we endeavor to address this gap by elucidating the significance of We-map reference frames,defining them with mathematical constraints,summarizing their nature and characteristics,deriving their transformation relationships and representing them through mathematical formulars and equations.Our work contributes to the fundamental theory of We-map and provides valuable systems and support for the mathematical foundation of We-map,map production,and platform development.Ultimately,this research serves to advance the development of We-map. 展开更多
关键词 We-map reference frames spatial direction relation coordinate system
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Resilience-incorporated seismic risk assessment of precast concrete frames with“dry”connections
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作者 Wu Chenhao Tang Yuchuan +1 位作者 Cao Xuyang Wu Gang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期403-425,共23页
A resilience-incorporated risk assessment framework is proposed and demonstrated in this study to manifest the advantageous seismic resilience of precast concrete frame(PCF)structures with“dry”connections in terms o... A resilience-incorporated risk assessment framework is proposed and demonstrated in this study to manifest the advantageous seismic resilience of precast concrete frame(PCF)structures with“dry”connections in terms of their low damage and rapid recovery.The framework integrates various uncertainties in the seismic hazard,fragility,capacity,demand,loss functions,and post-earthquake recovery.In this study,the PCF structures are distinguished from ordinary reinforced concrete frame(RCF)structures by characterizing multiple limit states for the PCF based on its unique damage mechanisms.Accordingly,probabilistic story-wise pushover analyses are performed to yield story-wise capacities for the predefined limit states.In the seismic resilience analysis,a step-wise recovery model is proposed to idealize the functionality recovery process,with separate considerations of the repair and non-repair events.The recovery model leverages the economic loss and downtime to delineate the stochastic post-earthquake recovery curves for the resilience loss estimation.As such,contingencies in the probabilistic post-earthquake repairs are incorporated and the empirical judgments on the recovery parameters are largely circumvented.The proposed framework is demonstrated through a comparative study between two“dry”connected PCFs and one RCF designed as alternative structural systems for a prototype building.The results from the risk quantification indicate that the PCFs show reduced loss hazards and lower expected losses relative to the RCF.Particularly,the PCF equipped with energy dissipation devices at the“dry”connections largely reduces the expected economic loss,downtime,and resilience loss by 29%,56%,and 60%,respectively,compared to the RCF. 展开更多
关键词 precast concrete frame non-emulative precast system seismic resilience seismic risk functional recovery
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Standardized ileal digestibility of amino acids in soybean meal fed to non-pregnant and pregnant sows
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作者 Ke Wang Ya Wang +11 位作者 Lei Guo Yong Zhuo Lun Hua Lianqiang Che Shengyu Xu Ruinan Zhang Jian Li Bin Feng Zhengfeng Fang Xuemei Jiang Yan Lin De Wu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期362-373,共12页
Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant sows.Seven solvent-extracte... Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant sows.Seven solvent-extracted SBMs from soybeans produced in the USA,Brazil,and China were selected.In Exp.1,eight different diets were created:a nitrogen(N)-free diet and 7 experimental diets containing SBM from different origins as the only N source.Eight non-pregnant,multiparous sows were arranged in an 8×8 Latin square design(8 periods and 8 diets).In Exp.2,the diet formula was the same as in Exp.1.Eight gestating sows(parity 3)were assigned to 4 different diets in a replicated 4×3 Youden square design(three periods and four diets)in mid-gestation and again in late-gestation stages.Results When fed to non-pregnant and late-gestating sows,the standardized ileal digestibility(SID)of CP and most AAs from different SBM were not significantly different(P>0.05).When fed to mid-gestating sows,the SID values for Arg,His,Lys,Phe,Cys,Gly,Ser,and Tyr in SBM 1 were lower than in SBM 4 and 5(P<0.05),whereas SID for Leu from SBM 5 was higher than in SBM 1 and 4(P<0.05).SID values for Ile,Ala,and Asp from SBM 4 were lower than in SBM 1 and 5(P<0.05).Sows had significantly greater SID values for Lys,Ala,and Asp during mid-gestation when compared with late-gestation stages(P<0.05).Mid-gestating sows had greater SID value for Val and lower SID value for Tyr when compared with non-pregnant and late-gestating sows(P<0.01),whereas non-pregnant sows had significantly greater SID value for Met when compared with gestating sows(P<0.01).Conclusions When fed to mid-gestating sows,the SID values for most AAs varied among SBM samples.The SID values for Lys,Met,Val,Ala,Asp,and Tyr in SBM were affected by sow gestation stages.Our findings provide a cornerstone for accurate SBM use in sow diets. 展开更多
关键词 Amino acids SOWS Soybean meal standardized ileal digestibility
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Experimental and numerical study regarding H-steel all-bolted connection steel frame with composite wall boards
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作者 Fan Min Guo Hongchao +2 位作者 Li Shen Wang Zhenshan Wang Huaqiang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期427-443,共17页
H-steel all-bolted connection steel frame structures with heat preservation and decoration composite wall boards were investigated and the seismic performances of three scaled specimens were studied.The failure modes,... H-steel all-bolted connection steel frame structures with heat preservation and decoration composite wall boards were investigated and the seismic performances of three scaled specimens were studied.The failure modes,hysteresis curves,bearing capacity,ductility,energy dissipation capacity,stiffness degradation and strain distribution were discussed.The calculation method of structural theoretical internal force was presented.The results showed that the overall structural seismic performance was better,and the structural ductility met the demands of elastic-plastic inter-story drift angle for seismic design.The H-steel weak-axis connection structure obtained better energy dissipation capacity,and its bearing capacity and stiffness were slightly different from the strong-axis connection.The heat preservation and decoration performance of composite wallboard and the all-bolted connection of the steel frame realized prefabrication during the whole construction period.The plastic hinge of the steel beam can be moved outwards because of the L-angles,which effectively avoids stress concentration in joint areas and expands the plastic hinge range.The errors between the theoretical structural capacity calculated by the plastic analysis method and the test results were within 2.44%.In addition,structural failure mechanisms and bearing capacities were verified by the finite element(FE)analysis,and the effects of the main parameters on the structures were investigated.The FE verification results were the same as in the test.The research results provide theoretical support and technical guidance for the application of thermal insulation and decorative composite wall panels in H-shaped steel all-bolted steel frames. 展开更多
关键词 composite wall boards all-bolted steel frame H-steel low-cyclic loading failure modes
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Research on batch multielement rapid quantitative analysis based on the standard curve-assisted calibration-free laserinduced breakdown spectroscopy method
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作者 Weiwei HAN Duixiong SUN +7 位作者 Guoding ZHANG Honglin WANG Kai GUO Yuzhuo ZHANG Haoliang WANG Denghong ZHANG Chenzhong DONG Maogen SU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期156-164,共9页
This study proposes a batch rapid quantitative analysis method for multiple elements by combining the advantages of standard curve(SC)and calibration-free laser-induced breakdown spectroscopy(CF-LIBS)technology to ach... This study proposes a batch rapid quantitative analysis method for multiple elements by combining the advantages of standard curve(SC)and calibration-free laser-induced breakdown spectroscopy(CF-LIBS)technology to achieve synchronous,rapid,and accurate measurement of elements in a large number of samples,namely,SC-assisted CF-LIBS.Al alloy standard samples,divided into calibration and test samples,were applied to validate the proposed method.SC was built based on the characteristic line of Pb and Cr in the calibration sample,and the contents of Pb and Cr in the test sample were calculated with relative errors of 6%and 4%,respectively.SC built using Cr with multiple characteristic lines yielded better calculation results.The relative contents of ten elements in the test sample were calculated using CF-LIBS.Subsequently,the SC-assisted CF-LIBS was executed,with the majority of the calculation relative errors falling within the range of 2%-5%.Finally,the Al and Na contents of the Al alloy were predicted.The results demonstrate that it effectively enables the rapid and accurate quantitative analysis of multiple elements after a single-element SC analysis of the tested samples.Furthermore,this quantitative analysis method was successfully applied to soil and Astragalus samples,realizing an accurate calculation of the contents of multiple elements.Thus,it is important to advance the LIBS quantitative analysis and its related applications. 展开更多
关键词 laser-induced breakdown spectroscopy standard curve quantitative analysis multielement
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