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On the Adaptability Range, Self-Selection, and Economic Nature of Biological Evolution
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作者 Hong Sheng 《Natural Science》 2024年第10期202-219,共18页
This article employs a combined approach of biology and economics to reveal that biological evolution has an economic nature, evolving towards improved energy efficiency. The orthodox Darwinian theory of evolution des... This article employs a combined approach of biology and economics to reveal that biological evolution has an economic nature, evolving towards improved energy efficiency. The orthodox Darwinian theory of evolution describes evolution as the random variation of organisms and their survival through natural selection. In fact, the natural environment itself is a constantly changing context, and the strategy to adapt to this change is to enhance behavioral capabilities, thereby expanding the range and dimensions of behavior. Therefore, the improvement of behavioral capabilities is an important aspect of evolution. The enhancement of behavioral capabilities expands the range of adaptation to the natural environment and increases the space for behavioral choices. Within this space of behavioral choices, some options are more effective and superior to others;thus, the ability to select is necessary to make the improved behavioral capabilities more beneficial to the organism itself. The birth and development of the brain serve the purpose of selection. By using the brain to make selections, at least the “better” behavior will be chosen between two alternatives. Once the better behavior yields better results, and the organism can associate these results with the corresponding behavior, it will persist in this behavior. The persistent repetition of a behavior over generations will form a habit. Habits passed down through generations constitute a new environment, causing the organism’s genes to activate or deactivate certain functions, ultimately leading to genetic changes that are beneficial to that habit. Since the brain’s selection represents the organism’s self-selection, it differs from random variation;it is also a rational selection, choosing behaviors that either obtain more energy or reduce energy consumption. Thus, this evolution possesses an economic nature. 展开更多
关键词 Evolution ECONOMICS Upgraded Variation Behavioral Capabilities Adaptability range SELF-selection
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Indicator Selection for Quality Measurement in Maternal Neonatal and Child Health Services: Application of Random Forest Classifier
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作者 Sarah Nyanjara Dina Machuve Pirkko Nykanen 《Journal of Computer and Communications》 2023年第7期74-87,共14页
Quality of Maternal, Neonatal and Child (MNCH) care is an important aspect in ensuring healthy outcomes and survival of mothers and children. To maintain quality in health services provided, organizations and other st... Quality of Maternal, Neonatal and Child (MNCH) care is an important aspect in ensuring healthy outcomes and survival of mothers and children. To maintain quality in health services provided, organizations and other stakeholders in maternal and child health recommend regular quality measurement. Quality indicators are the key components in the quality measurement process. However, the literature shows neither an indicator selection process nor a set of quality indicators for quality measurement that is universally accepted. The lack of a universally accepted quality indicator selection process and set of quality indicators results in the establishment of a variety of quality indicator selection processes and several sets of quality indicators whenever the need for quality measurement arises. This adds extra processes that render quality measurement process. This study, therefore, aims to establish a set of quality indicators from a broad set of quality indicators recommended by the World Health Organization (WHO). The study deployed a machine learning technique, specifically a random forest classifier to select important indicators for quality measurement. Twenty-nine indicators were identified as important features and among those, eight indicators namely maternal mortality ratio, still-birth rate, delivery at a health facility, deliveries assisted by skilled attendants, proportional breach delivery, normal delivery rate, born before arrival rate and antenatal care visit coverage were identified to be the most important indicators for quality measurement. 展开更多
关键词 Indicator selection Machine Learning Quality measurement Random Forest Quality Indicators Maternal Care Quality Neonatal Care Quality
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A Portfolio Selection Method Based on Pattern Matching with Dual Information of Direction and Distance
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作者 Xinyi He 《Applied Mathematics》 2024年第5期313-330,共18页
Pattern matching method is one of the classic classifications of existing online portfolio selection strategies. This article aims to study the key aspects of this method—measurement of similarity and selection of si... Pattern matching method is one of the classic classifications of existing online portfolio selection strategies. This article aims to study the key aspects of this method—measurement of similarity and selection of similarity sets, and proposes a Portfolio Selection Method based on Pattern Matching with Dual Information of Direction and Distance (PMDI). By studying different combination methods of indicators such as Euclidean distance, Chebyshev distance, and correlation coefficient, important information such as direction and distance in stock historical price information is extracted, thereby filtering out the similarity set required for pattern matching based investment portfolio selection algorithms. A large number of experiments conducted on two datasets of real stock markets have shown that PMDI outperforms other algorithms in balancing income and risk. Therefore, it is suitable for the financial environment in the real world. 展开更多
关键词 Online Portfolio selection Pattern Matching Similarity measurement
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Objective Model Selection in Physics: Exploring the Finite Information Quantity Approach
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2024年第5期1848-1889,共42页
Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Informati... Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Information Quantity (FIQ) approach offers a novel solution by acknowledging the inherent limitations in information processing capacity of physical systems. This framework facilitates the development of objective criteria for model selection (comparative uncertainty) and paves the way for a more comprehensive understanding of phenomena through exploring diverse explanations. This work presents a detailed comparison of the FIQ approach with ten established model selection methods, highlighting the advantages and limitations of each. We demonstrate the potential of FIQ to enhance the objectivity and robustness of scientific inquiry through three practical examples: selecting appropriate models for measuring fundamental constants, sound velocity, and underwater electrical discharges. Further research is warranted to explore the full applicability of FIQ across various scientific disciplines. 展开更多
关键词 Comparative Uncertainty Finite Information Quantity Formulating a Model measurement Accuracy Limit Objective Model selection
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Improving IAC Algorithm Based on Range Rate Measurement 被引量:1
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作者 张鸿业 王月涌 蔡颖臻 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期276-281,共6页
Aim Interactive multiple model(IMM) algorithm was introduced into two? stage estimation to improve the estimating accuracy for system position and velocity.Methods The state estimation was carried out in mixed coor... Aim Interactive multiple model(IMM) algorithm was introduced into two? stage estimation to improve the estimating accuracy for system position and velocity.Methods The state estimation was carried out in mixed coordinates according to the nonlinear measure equation, a generalized interactive acceleration compensation(IAC) algorithm in mixed coordinate was presented. Results Simulation result shows the estimation accuracy is improved through changing measure equation in polar coordinates. Conclusion The estimation accuracy for position and velocity estimation, has been improved greatly, and the proposed algorithm has the advantage of less calculating time comparing with other multiple model methods. 展开更多
关键词 range rate measurement interactive acceleration compensation two-stage estimation
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Highly sensitive digital optical sensor with large measurement range based on the dual-microring resonator with waveguide-coupled feedback 被引量:3
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作者 向星烨 王葵如 +3 位作者 苑金辉 晋博源 桑新柱 余重秀 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期284-288,共5页
We propose a novel high-performance digital optical sensor based on the Mach-Zehnder interferential effect and the dual-microring resonators with the waveguide-coupled feedback. The simulation results show that the se... We propose a novel high-performance digital optical sensor based on the Mach-Zehnder interferential effect and the dual-microring resonators with the waveguide-coupled feedback. The simulation results show that the sensitivity of the sensor can be orders of magnitude higher than that of aconventional sensor, and high quality factor is not critical in it. Moreover, by optimizing the length of the feedback waveguide to be equal to the perimeter of the ring, the measurement range of the proposed sensor is twice as much as that of the conventional sensor in the weak coupling case. 展开更多
关键词 optical sensor microring resonator high sensitivity large measurement range
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Game theory model of exit selection in pedestrian evacuation considering visual range and choice firmness 被引量:1
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作者 Wei-Li Wang Fang-Fang Wan Siu-Ming Lo 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第8期355-362,共8页
Exit choice is one of the most important pedestrian behaviors during evacuation.Distance to the exit is a generally recognized factor influencing expected moving time to the exit.Visual range determines how much infor... Exit choice is one of the most important pedestrian behaviors during evacuation.Distance to the exit is a generally recognized factor influencing expected moving time to the exit.Visual range determines how much information a pedestrian can perceive,thus the number of pedestrians within the visual field can be used to estimate waiting time at the exit.Besides,the choice firmness that reflects the degree to which a pedestrian would persist in his/her previous choice of exit is proposed.By integrating game theory into a cellular automata simulation framework,the pedestrian exit choice mechanism is investigated and explicitly modeled in this paper.A systematic analysis of the key factors influencing pedestrian evacuation is conducted,including visual radius and choice firmness of a pedestrian,initial crowd distribution of the room,exit layout as well as exit width.It is found that low choice firmness level can lead to unnatural pedestrian behavior such as wandering,which is adverse to evacuation.The longer the pedestrian's visual radius,the earlier the pedestrian can determine his/her final selection of the exit.Compared with the scenario where the pedestrians are randomly distributed,pedestrians clustered together in a corner of the room lead to high crowd density and imbalanced use of exits.Furthermore,the exit layout and exit width also have a certain influence on pedestrian evacuation process.The results of this paper may be of benefit to the formulation of behavioral rules in other pedestrian simulation models. 展开更多
关键词 game theory exit selection visual range choice firmness
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Feature Selection Based on Distance Measurement 被引量:1
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作者 Mingming Yang Junchuan Yang 《Journal of New Media》 2021年第1期19-27,共9页
Every day we receive a large amount of information through different social media and software,and this data and information can be realized with the advent of data mining methods.In the process of data mining,to solv... Every day we receive a large amount of information through different social media and software,and this data and information can be realized with the advent of data mining methods.In the process of data mining,to solve some high-dimensional problems,feature selection is carried out in limited training samples,and effective features are selected.This paper focuses on two Relief feature selection algorithms:Relief and ReliefF algorithm.The differences between them and their respective applicable scopes are analyzed.Based on Relief algorithm,the high weight feature subset is obtained,and the correlation between features is calculated according to the mutual information distance measure,and the high redundant features are removed to obtain the feature subset with higher quality.Experimental results on six datasets show the effectiveness of our method. 展开更多
关键词 Feature selection mutual information distance measurement RELIEF
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Flexible nest site selection of the endangered Oriental Storks(Ciconia boyciana):Trade-off from adaptive strategies 被引量:3
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作者 Lei Cheng Lizhi Zhou +2 位作者 Chao Yu Zhenhua Wei Chunhua Li 《Avian Research》 SCIE CSCD 2023年第2期242-249,共8页
Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selectio... Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications.In this study,we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks(Ciconia boyciana)in different nest areas.Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas,and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas.The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks.The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain;however,nest height decreased with the abundance of food resources in the Northeast China nest area.Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies.In safer environments,nests were lower and closer to food resources,which allows parent storks to invest more in the nestlings.However,in areas where human activity was intense,nests were higher to ensure the safety of their offspring.Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting.Finally,the establishment of soft barriers around the nesting areas could increase the safety of nests. 展开更多
关键词 Adaptive strategies Breeding range expansion Habitat characteristics Nest site selection Oriental storks
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MLSI-RT: memorize LOS range measurements identified residual test location algorithm and performance analysis
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作者 马兵 邢建平 张军 《Journal of Shanghai University(English Edition)》 CAS 2011年第3期190-193,共4页
The dominant error source of mobile terminal location in wireless sensor networks (WSNs) is the non-line-of-sight (NLOS) propagation error. Among the algorithms proposed to mitigate the influence of NLOS propagati... The dominant error source of mobile terminal location in wireless sensor networks (WSNs) is the non-line-of-sight (NLOS) propagation error. Among the algorithms proposed to mitigate the influence of NLOS propagation error, residual test (RT) is an efficient one, however with high computational complexity (CC). An improved algorithm that memorizes the light of sight (LOS) range measurements (RMs) identified memorize LOS range measurements identified residual test (MLSI-RT) is presented in this paper to address this problem. The MLSI-RT is based on the assumption that when all RMs are from LOS propagations, the normalized residual follows the central Chi-Square distribution while for NLOS cases it is non-central. This study can reduce the CC by more than 90%. 展开更多
关键词 memorize LOS range measurements identified residual test (MLSI-RT) computational complexity (CC) nonline-of-sight (NLOS) residual test (RT) algorithm simplified residual test (SRT)
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Theoretical and experimental assessment of a novel method to establish the complete measurement range of the calorimeter and its limit of detection and quantification
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作者 Vesna Krstic 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第4期466-473,共8页
For determining the accuracy of a calorimeter over the instrument’s entire measuring range,a novel method has been established.For this new approach,(a)benzoic acid(C_(6)H_(5)CO_(2)H) as a certified reference materia... For determining the accuracy of a calorimeter over the instrument’s entire measuring range,a novel method has been established.For this new approach,(a)benzoic acid(C_(6)H_(5)CO_(2)H) as a certified reference material(CRM),(b)SiO_(2) and(c)a mixture of CRM benzoic acid and SiO_(2) have been used.To illustrate the essential difference between 1)the novel analytical method for control of the entire measurement range and 2)the calorimeter calibration,both applications of benzoic acid(BA)have been demonstrated.An experimental result showed that BA was successfully used to check the whole calorimeter measurement range.The results also showed that the same new method was successfully applied to determine the limit of detection and quantification.A new instrument testing process and a new measurement technique have thus been established.In this way,the cost of using CRM to control the accuracy of measuring the entire measuring range of the calorimeter,as shown in this paper,is minimized.The requirements of the ISO/IEC 17025:2017 standard are satisfied.ISO/IEC 17025:2017,together with ISO 9001:2015(quality management systems),ISO 14001:2015(relate to environmental protection)and ISO45001:2018(occupational safety),constitute an integrated quality system by which a testing laboratory may also accredit. 展开更多
关键词 Benzoic acid Certified reference material The limit of detection/quantification measurement range Quality control CALORIMETER Environmental protection
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ANALYSIS AND MEASUREMENT OF LARGE DYNAMIC RANGE RF SWITCH INTER-MODULATION
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作者 Han Zhouan 《Journal of Electronics(China)》 2008年第3期422-427,共6页
Radio Frequency (RF) switch circuit is the basic part of microwave devices and systems. The non-linearity distortion figure is necessary in the field of large dynamic range of signal. This letter analyzes the basic sw... Radio Frequency (RF) switch circuit is the basic part of microwave devices and systems. The non-linearity distortion figure is necessary in the field of large dynamic range of signal. This letter analyzes the basic switch circuit and its inter-modulation, and studies in detail the measurement methods and systems of RF switch intercept point. It has provided cascaded simulation testing methods, which can accurately measure the PF switch, of which the second or third order intercept point value is above 75dB and 60dB, respectively. As the testing results are consistent with the theoretical analyses, it proves that the validity of the method satisfies the requirements of large scaled linearity measurement in engineering. 展开更多
关键词 Large dynamic range Radio Frequency (RF) switch Intercept point measurement
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Dynamic Free-Spectral-Range Measurement for Fiber Resonator Based on Digital-Heterodyne Optical Phase-Locked Loop
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作者 Hongchen Jiao Tao Wang +2 位作者 Heli Gao Lishuang Feng Honghao Ma 《Optics and Photonics Journal》 2021年第8期332-340,共9页
<div style="text-align:justify;"> We propose a novel scheme, based on digital-heterodyne optical phase-locked loop with whole-fiber circuit, to dynamically measure the free-spectral-range of a fiber re... <div style="text-align:justify;"> We propose a novel scheme, based on digital-heterodyne optical phase-locked loop with whole-fiber circuit, to dynamically measure the free-spectral-range of a fiber resonator. The optical phase-locked loop is established with a differential frequency-modulation module consists of a pair of acousto-optic modulators. The resonance-tracking loop is derived with the Pound-Drever-Hall technique for locking the heterodyne frequency of the OPLL on the frequency difference between adjacent resonance modes. A stable locking accuracy of about 7 × 10<sup>?9</sup> and a dynamic locking accuracy of about 5 × 10<sup>?8</sup> are achieved with the FSR of 8.155 MHz, indicating a bias stability of the resonator fiber optic gyro of about 0.1?/h with 10 Hz bandwidth. In addition, the thermal drift coefficient of the FSR is measured as 0.1 Hz/?C. This shows remarkable potential for realizing advanced optical measurement systems, such as the resonant fiber optic gyro, and so on. </div> 展开更多
关键词 Free Spectral range Fiber Resonator Dynamic measurement Digital-Heterodyne Optical Phase-Locked Loop Resonant Fiber Optic Gyro
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Arrangement Selection and Construction Quality Control Measures of Bridge Support
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作者 Tieyuan Sun 《Journal of Architectural Research and Development》 2022年第6期47-52,共6页
Bridge bearings are a small part of the whole bridge structure,but it can affect the corner of the bridge,and the stability and quality of the bridge deck,so the performance of the bridge bearing can directly determin... Bridge bearings are a small part of the whole bridge structure,but it can affect the corner of the bridge,and the stability and quality of the bridge deck,so the performance of the bridge bearing can directly determine the quality and lifespan of the entire bridge.The bridge bearing connects the upper and lower parts of the whole bridge.In order to improve the quality and structure of the whole bridge,the layout and selection of bridge bearings needs to be done well,the construction process needs to be closely monitored,and the whole process needs to be well-managed.The existing problems should be analyzed in detail and solved in time to ensure the quality of the bridge project. 展开更多
关键词 Bridge bearing Layout selection Construction quality control Measures
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某线震后轨道设计方案研究 被引量:1
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作者 蔡向辉 张岷 +3 位作者 唐文国 刘启宾 褚卫松 张生延 《铁道标准设计》 北大核心 2024年第3期43-48,共6页
2022年1月8日门源发生6.9级地震,造成某线隧道二衬坍塌、桥梁梁体移位、接触网脱落等基础、设备严重损坏,并伴随钢轨折断、扣件脱落、道床倾斜等轨道震害,是我国高速铁路首次遭遇的强震作用下严重受灾事件。结合震后预测余滑变形量水平1... 2022年1月8日门源发生6.9级地震,造成某线隧道二衬坍塌、桥梁梁体移位、接触网脱落等基础、设备严重损坏,并伴随钢轨折断、扣件脱落、道床倾斜等轨道震害,是我国高速铁路首次遭遇的强震作用下严重受灾事件。结合震后预测余滑变形量水平150~300 mm,垂向100 mm条件下,在设防区段提出一种“三孔连体套管承轨台可调式WJ-8型扣件+长枕埋入式单层道床预留切割孔”新型大调整量无砟轨道结构方案。其中,三孔连体套管承轨台可调式WJ-8型扣件在既有WJ-8型扣件基础上通过增设铁承轨台、调距块和三联套管等部件可满足单股钢轨左右位置调整量达152 mm,长枕埋入式单层道床中预留切割孔,便于在基础变形超出扣件调整范围后切割纠偏;通过对余滑变形后线路拟合获得拨距包络图,确定了大调整量无砟轨道铺设范围。 展开更多
关键词 地震 余滑 破坏形态 活动断裂带 扣件 设防范围 轨道选型
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面向空间目标近距离操作的相对位姿测量系统设计
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作者 庄海孝 石伟 +5 位作者 罗毓芳 张强 王瑶 吴茹菲 冯聪 李怀锋 《航天器工程》 CSCD 北大核心 2024年第5期22-28,共7页
面向空间近距离操作的相对位姿测量系统(RPS)是对目标进行距离测量、位姿测量、三维重构及光学成像的有效方式。针对高精度一体化位姿测量需求,文章提出了融合激光雷达测距的单目视觉位姿测量系统,可同时具备目标距离、方位测量及三维... 面向空间近距离操作的相对位姿测量系统(RPS)是对目标进行距离测量、位姿测量、三维重构及光学成像的有效方式。针对高精度一体化位姿测量需求,文章提出了融合激光雷达测距的单目视觉位姿测量系统,可同时具备目标距离、方位测量及三维成像等能力。经过在轨应用验证,结果表明:方位测角精度和位姿测量精度等关键指标均优于预期值,该系统主要功能性能可满足空间操作实际应用需求,可以为未来空间机动平台的目标测量系统研制提供参考。 展开更多
关键词 空间近距离操作 位姿测量 单目视觉
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育种播种机钢索复卷测程装置的结构设计与试验
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作者 叶岩 吴泽全 +4 位作者 蔡晓华 刘立强 侯云涛 李源源 赵丽平 《农机化研究》 北大核心 2024年第8期125-128,133,共5页
目前,小区育种播种机定长获取方式主要通过人工测量,效率低且作业强度大,严重制约了小区育种机械的快速发展。为此,设计了一种钢索复卷测程装置,采用自动收放式测程,通过探测装置检测钢索固定的钢制或橡胶等材质球体获取小区育种播种机... 目前,小区育种播种机定长获取方式主要通过人工测量,效率低且作业强度大,严重制约了小区育种机械的快速发展。为此,设计了一种钢索复卷测程装置,采用自动收放式测程,通过探测装置检测钢索固定的钢制或橡胶等材质球体获取小区育种播种机区间位置数据信号。为了确定不同前进速度下钢索复卷测程装置连续工作的合理参数范围,通过样机试验对装置进行参数优化。试验结果表明:往复导线轮V型角度在10°~20°之间,往复丝杠长度在400~450mm之间,装置运行稳定且无钢索缠绕和收排线集中等问题,带有触点式的行程开关的信号传输和控制运行稳定可靠,达到了育种播种机测程的要求。 展开更多
关键词 育种播种机 钢索复卷 测程装置
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激光雷达超远距离测距技术
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作者 魏龙超 王鹏宇 《宇航计测技术》 CSCD 2024年第3期75-81,共7页
针对超远距离多功能交会对接激光雷达需求,开展基于非相干测距技术的远距离激光测距通信一体化模块研制,在不改变原有雷达主机架构和信号体制下,实现对远距离高动态合作目标的通信测距功能。推导出测距原理,对动态、时钟性能等因素产生... 针对超远距离多功能交会对接激光雷达需求,开展基于非相干测距技术的远距离激光测距通信一体化模块研制,在不改变原有雷达主机架构和信号体制下,实现对远距离高动态合作目标的通信测距功能。推导出测距原理,对动态、时钟性能等因素产生的测距误差进行理论分析,给出速度、时钟性能对测距误差的影响公式。得出在高动态环境下,相对速度与测距周期、双方钟差共同作用产生测距系统误差,且速度越大系统误差越大的结论。设计测距通信一体化演示验证平台,完成测距通信算法的软硬件评估,实测结果与理论推导相符,为后续新体制激光雷达原理样机研制奠定技术基础。 展开更多
关键词 激光测距通信 激光雷达 双向单程测距
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基于LabVIEW的继电保护测试仪自动检测系统设计 被引量:1
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作者 李艳萍 韩春雪 《计算机测量与控制》 2024年第7期44-49,共6页
针对现有的继电保护测试仪检测程序繁琐,自动化程度低,点对点调试效率低下等问题,提出基于LabVIEW的继电保护测试仪自动检测系统;系统硬件以STM32F407ZGT6为主控芯片研制了继电保护测试仪输出转换装置,自动控制测试仪与标准器连成试验回... 针对现有的继电保护测试仪检测程序繁琐,自动化程度低,点对点调试效率低下等问题,提出基于LabVIEW的继电保护测试仪自动检测系统;系统硬件以STM32F407ZGT6为主控芯片研制了继电保护测试仪输出转换装置,自动控制测试仪与标准器连成试验回路,代替人工拆接线行为;系统软件以LabVIEW为开发平台,设计了仪器通信、自动检测、生成报告、强制选择测点等模块,实现了继电保护测试仪的全自动检测;通过对某型继电保护测试仪进行测试,结果表明该系统工作状态稳定,能够实现一键式全自动检测,用户界面友好,可以替代繁琐的人工检测方法,具有一定的工程应用前景。 展开更多
关键词 LABVIEW 继电保护测试仪 自动检测 强制选择测点 输出转换装置
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微波频段小型化频率选择表面设计
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作者 霍佳雨 姚宗杉 +2 位作者 张文尊 刘列 高博 《吉林大学学报(信息科学版)》 CAS 2024年第5期775-780,共6页
为提高频率选择表面的性能,使其可精确控制电磁波在微波频段下的传播特性,实现对电磁波的反射、透射或吸收,设计了一种微波频段小型化频率选择表面。该频率选择表面单元尺寸为0.024λ×0.024λ,小型化性能良好。在1~10 GHz范围内有... 为提高频率选择表面的性能,使其可精确控制电磁波在微波频段下的传播特性,实现对电磁波的反射、透射或吸收,设计了一种微波频段小型化频率选择表面。该频率选择表面单元尺寸为0.024λ×0.024λ,小型化性能良好。在1~10 GHz范围内有3个通带,具有极好的极化稳定性和角度稳定性,可保持工作频率和带宽不变,传输性能良好。该研究结果可作为频率选择表面分析的依据,为其小型化设计提供思路。 展开更多
关键词 频率选择表面 微波频段 小型化 多波段 自由空间测试法
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