某型摆式加速度计自动盖总成装配系统

摆式加速度计广泛应用于航空航天、船舶等领域的惯性导航系统中,其装配作业目前主要依赖于人工操作,产品一致性难以保证。鉴于此,本文针对某型摆式加速度计研制了一套自动装配系统。基于宏微结合的设计策略,搭建基于高精度运动滑台的微动平台,以及基于单轴机器人的宏动平台。确立了以微动平台为精调核心,以宏动平台辅助压装并实现不同功能模块工作位置调整的装配机制,同时设计功能模块上中下三层的立体分层式结构,在保证精度的同时避免作业空间的拥挤。引入六轴协作机器人并集成视觉系统,实现作业空间的全覆盖识别和自动化上下料功能。针对磁钢零件磁性力对装配精度的影响,采用零件内部辅助限位的方式,实现零件装配精度的保持。基于刚体变换,对系统进行误差分析并推导了误差补偿模型。实验结果验证,该装配系统的角度装配精度优于±0.03°,压装力精度优于±0.5 N,扭力精度优于±0.003 N·m,满足装配要求,为该型摆式加速度计的批量化生产提供了有力保障。

Study on Influencing Factors and Control Points of Design Estimate of Landscaping Engineering

In recent years,China’s landscaping projects have developed vigorously,and the growth rate of urban garden green space areas has been maintained at about 5%.Overall,with the development of the national economy and the support of macro policies,people’s demand for close to nature and beautify the environment is gradually increasing,which has brought new growth momentum for the development of the landscaping industry.Simultaneously,from the perspective of future economic development and urban development,the landscaping industry still has a lot of room for development.However,with the rapid development of landscape engineering,the problem of cost control of landscape engineering is becoming more prominent,the phenomenon of budget overestimation is common,and there are many factors affecting the cost of landscape engineering,which brings difficulties and challenges to the analysis of its influencing factors and cost management.How to scientifically analyze the influencing factors and control the cost has become an important link in the landscaping project.To solve the above problems,this paper takes the design stage of landscaping engineering as the background,takes the design estimate of landscaping engineering as the research object,through literature research and data collection,fully excavates the main influencing factors of the design estimate stage of landscaping engineering,analyzes the key points of cost control,and provides reference ideas and directions for the later cost management and control.

Research on Intelligent Cost Estimation of Engineering Foundation Projects Based on CSIs Theory

Against the backdrop of rapid development in China’s construction and infrastructure sectors,discrepancies between project budgets and actual costs have become pronounced,manifesting in project overruns and suspensions,posing significant challenges.To address inaccuracies in investment targets and operational complexities,this study focuses on a beam-bridge construction project in a district of Shijiazhuang city as a case study.Drawing upon historical analogs,the project employs a Work Breakdown Structure(WBS)to decompose the engineering works.Building on theories of Cost Significant(CS)and Whole Life Costing(WLC),the study constructs Cost Significant Items(CSIs)and develops a CNN-BiLSTM-Attention neural network for nonlinear prediction.By identifying significant cost drivers in engineering projects,this paper presents a streamlined cost estimation method that significantly reduces computational burdens,simplifies data collection processes,and optimizes data analysis and forecasting,thereby enhancing prediction accuracy.Finally,validation with real-world cost fluctuation data demonstrates minor errors,meeting predictive requirements across project execution phases.

太阳能集热蓄热墙在延安农居的应用研究

针对延安农居建筑围护结构构造简单,建筑能耗高,室内热环境差及新能源利用率低等现状,因地制宜,结合陕北地区太阳能资源自身的优势及技术的可实施性,提出经济效益高,技术简单,节能环保的太阳能集热蓄热墙技术。文中通过此技术原理和适宜性的分析和实地调研后,得出该墙适宜在延安农居中推广的结论。

A novel design of 3D carbon host for stable lithium metal anode

Rational design of porous conductive hosts with high electrical conductivity,large surface area,and adequate interior space is desirable to suppressing dendritic lithium growth and accommodating large volume change of lithium metal anode during the Li plating/stripping process.However,due to the conductive nature of the conductive hosts,Li is easily deposited directly on the top of the hosts,which hinders it from fully functioning.To circumvent the issue,in this study,we designed a novel porous carbon host with a gradient-pore-size structure based on one-dimensional(1D)carbon with different diameters.With this kind of host,stable cycling with high and stable Coulombic efficiency of~98%is achieved at 0.5 mA cm^(−2) with an areal capacity of 1 mAh cm^(−2) over 320 cycles.In contrast,the normal three-dimensional(3D)carbon nanotube host presents a moss-like Li morphology with wildly fluctuating Coulombic efficiency after 100 cycles.The results reveal that the unique gradient-pore-size structure of the 3D conductive host greatly improves the performance of lithium metal batteries.

Correlation between tobacco and alcohol use and Traditional Chinese Medicine constitutions: an analysis based on a sample from general population of China

OBJECTIVE:To investigate the relationship between smoking and drinking and constitution types from Traditional Chinese Medicine(TCM)theory.METHODS:The Constitution in Chinese Medicine Questionnaire(CCMQ)was used.A sample of 8448subjects from nine provinces and municipalities was chosen from the database of the TCM constitution and health status survey.Constituent ratio and correspondence analysis were used to find the relationship between smoking and drinking and TCM constitution.RESULTS:There was an association between smokinganddrinkingandtheGentleness,phlegm-dampness,and dampness-heat type constitutions.People that did not smoke tobacco or drink alcohol tended to have Yang-deficiency,Yin-deficiency,Qi-depression,Qi-deficiency,special diathesis,orblood-stasis type constitutions.CONCLUSION:There was a significant correlation between tobacco and alcohol use and TCM constitutions.To improve patient health,more attention should be paid to tobacco and alcohol control.

Co-guiding the dendrite-free plating of lithium on lithiophilic ZnO and fluoride modified 3D porous copper for stable Li metal anode

Lithium metal battery is considered to be the most promising energy storage technologies due to its ultra-high theoretical capacity and extremely low standard potential.However,the infinite volume change during uneven deposition/dissolution process and the growth of lithium dendrite resulting in severe capacity decay and high safety hazards,which hinders the application in next generation secondary batteries.In this paper,the three dimensional(3D)porous copper is prepared through an electrochemical etching CueZn alloy,and the pore walls are modified with lithiophilic layer of ZnO and fluorine.The as-prepared 3D Cu/ZnO/F can inhibit the growth of Li dendrite and mitigate the huge volume change of Li metal anode during cycling process,resulting in stable solid electrolyte interface(SEI)layer and electrode structure.The Li|3D Cu/ZnO/F cell can be stably cycled over 300 cycles with 98% of coulomb efficiency at 0.5 mA cm^(-2),1 mAh cm^(-2).The synergistic effects of both ZnO and fluorine on inducing the uniform deposition of lithium by providing bonding sites can inhibit the generation of lithium dendrites and thus improve the electrochemical performance of lithium metal batteries.

Case-control study on the associations between lifestyle-behavioral risk factors and phlegm-wetness cbonstitution

OBJECTIVE: To explore the relationships between different lifestyle-behavioral factors and phlegm wetness type of Traditional Chinese Medicine constitution,so as to provide health management strategies for phlegm-wetness constitution.METHODS: A case-control study was conducted with the cases selected from the database of Chinese constitution survey in 9 provinces or municipalities of China. 1380 cases met the diagnostic criteria of phlegm-wetness type were taken as the case group, and 1380 cases were randomly selected from gentleness type as the control group. Using Chi-square test to compare the differences of lifestyle-behavior composition in each group; single factor and multiple logistic regression analysis were used to compare the relationships of life-style-behavioral factors and phlegm-wetness type.RESULTS: There were statistically significant differences between phlegm-wetness type group and gentleness type group in lifestyle behaviors(dietary habits, tobacco and liquor consumptions, exercise habits, sleeping habits). The results of single factor logistic regression analysis demonstrated that the risk of phlegm-wetness constitution decreased significantly in light diet(odds ratio, OR=0.68);The risk factors of phlegm-wetness type were fatty food intake(OR=2.36), sleeping early and getting up late(OR=1.87), tobacco smoking(OR=1.83),barbecued food intake(OR=1.68), alcohol drinking(OR=1.63), salty food intake(OR=1.44), sleeping erratically(OR=1.43), less physical activities(OR=1.42), sweet food intake(OR=1.29), sleeping and getting up late(OR=1.26), and pungent food intake(OR=1.21), respectively. Regardless of the interaction among lifestyle-behavioral factors, the results of the multiple logistic regression analysis revealed that the risk factors of phlegm-wetness type were sleeping early and getting up late(OR=1.94), fatty food intake(OR=1.80), tobacco smoking(OR=1.50),sleeping erratically(OR=1.50), barbecued food intake(OR=1.40), sleeping and getting up late(OR=1.40), less physical activities(OR=1.31), sleeping late and getting up early(OR=1.27),and sweet food intake(OR=1.27), respectively, and the risk ofphlegm-wetness type still decreased significantly inlightfoodintake(OR=0.79).CONCLUSION: Light diet can decrease the risk of being phlegm-wetness constitution, and bad lifestyle behaviors such as sleeping early and getting up late, sleeping erratically, fatty food, barbecued food or sweet food intake, tobacco and liquor consumptions, and less physical activities can increase the risks of becoming phlegm-wetness constitution.