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车体刚强度结构优化对连发武器射击精度的影响

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中北大学学报（自然科学版） 2024年第2期45卷 170-177页

作者：白文杰韩晓明任广武于君然中北大学机电工程学院山西太原030051 内蒙古第一机械集团有限公司内蒙古包头014030

为减小射击时车体振动对车载连发武器射击精度的影响,建立了某轮式车辆车体有限元模型,对火炮典型射击工况下车体的受力进行了分析,以提高车体结构刚强度为优化目标,在车体后方横向增加变截面梁来改进相应的薄弱结构。车体改进前后的模... 详细信息

为减小射击时车体振动对车载连发武器射击精度的影响,建立了某轮式车辆车体有限元模型,对火炮典型射击工况下车体的受力进行了分析,以提高车体结构刚强度为优化目标,在车体后方横向增加变截面梁来改进相应的薄弱结构。车体改进前后的模态测试与射击试验结果表明,经过车体结构优化可有效改善整车环境下对射击精度影响较大的身管一阶模态频率,5连发射击时的射击精度得到有效提高。

关键词：车体结构优化连发武器模态测试射击精度

Design and experiment of the double-seed hole seeding precision seed metering device for peanuts

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International Journal of Agricultural and Biological Engineering 2022年第3期15卷 107-114页

作者： Xiaoshun Zhao Wenjing Ran Jianjun Hao wenjie bai Xinlei Yang College of Mechanical and Electrical Engineering Hebei Agricultural UniversityBaoding 071001HebeiChina

A secondary seeding precision double-seed peanut hole seeding seed metering device was designed to improve the performance of the peanut planting equipment and provide a solution for problems on the high seed charge that can cause poor cavitation and uniformity *** main structure and operation parameters in terms of groove length,seed charge height,seed-bed belt speed,and rotation speed of the seed metering wheel were determined through theoretical ***-factor and orthogonal tests were carried out through the JPS-12 seed metering device test bench,and the peanut variety Jinonghua-3 was selected as the test *** single hole double-seed rate,qualified rate,the variation coefficient of hole spacing,and hole rate were chosen for evaluating the working *** results of the single-factor test showed that the seed metering performance is mainly affected by the groove length,the speed of the seed-bed belt and the rotation speed of the seed metering wheel,and the influence of the cavitation rate is *** optimal seeding height is determined to be 40 *** results of the orthogonal test showed that the groove length was 27.3 mm,the seed-bed belt speed was 1.51 km/h,and the rotation speed of the seed metering wheel was 14.11 r/***’s more,a regression model based on the orthogonal test results was established,the qualified rate of the number of holes obtained after optimizing the model was 98.84%,the variation coefficient of hole spacing was 9.74%,and the hole rate was 1.40%.Notably,the working performances of the device can meet the requirement of precision seeding.

关键词： peanut precision seed metering device orthogonal test regression method

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成品尿素包装破损污染的原因分析及处理

大氮肥 2024年第2期47卷 136-137,140页

作者：邓光炯白文杰白文宾肖德明李欣杰中国石油宁夏石化公司宁夏银川750026

结合尿素产品储运情况,详细分析影响成品尿素外观质量的因素,通过改进作业模式、维护保养和优化管理等措施,消除影响成品尿素外观质量的因素,提升尿素质量,保证企业品牌的质量效益。

关键词：成品尿素破袋污染外观质量

Study on positive-negative pressure seed metering device for wide-seedling-strip-seeding

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International Journal of Agricultural and Biological Engineering 2022年第6期15卷 124-133页

作者： Xiaoshun Zhao wenjie bai Jincai Li Huali Yu Dawei Zhao Baozhong Yin College of Mechanical and Electrical Engineering Hebei Agricultural UniversityBaoding 071001HebeiChina State Key Laboratory of North China Crop Improvement and Regulation Hebei Agricultural UniversityBaoding 071001HebeiChina College of Plant Protection Hebei Agricultural UniversityBaoding 071001HebeiChina

In order to solve the problem of poor uniformity of wheat strip sowing,this paper designs a positive-negative pressure wheat wide-seedling-strip-seeding precision seed metering device,which adopts the roller structure with the principle of combined positive-negative *** theoretical analysis and relevant data,the structure of the seed metering device and the structure of the positive-negative pressure air chamber were *** internal flow field conditions were simulated by Fluent software under different structural *** design of the seed holes was completed by analyzing the pressure cloud diagram and the flow velocity vector diagram,and the optimal combination of parameters was obtained and the influence law of negative pressure on the flow field was *** effect of rotational speed on the flow field was studied by EDEM-Fluent coupling *** this paper,a three-factor and three-level response surface test was conducted on a JPS-12 test bench with Liangxin-99 wheat as the research *** experiment was conducted with the rotational speed of seed metering device,the negative pressure of seed suction and the seeding height as factors,and the qualified index,the reseeding index and the miss-seeding index as evaluation *** the test,the optimal structure and working parameters of the seed metering device were determined as follows:the diameter of the seed hole was 2 mm,and the number of seed holes per row was 28,negative pressure was−3.5 kPa,rotational speed of seed metering device was 19 r/min,and seeding height was 180 *** test was carried out on the optimized seed metering device:the qualified index was 80.62%,the reseeding index was 9.22%,and the miss-seeding index was 10.16%,which reached the parameter indicator in JB/T 10293-2013 Technical conditions of single seed(precision)seeder and met the agronomic requirements for wheat wide-seedling-strip-seeding.

关键词： wheat precision seed metering device wheat wide-seedling-strip-seeding positive-negative pressure fluent EDEM-Fluent coupling response surface test

接受高压氧综合治疗的老年急性脑梗死患者血清YKL-40、VEGF的动态变化及其与预后的相关性

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河南医学研究 2024年第3期33卷 412-417页

作者：陶兴白永杰王佳楚金亭孟凡超杨旭孙世龙白文杰周伟民郑州市第二人民医院高压氧医学科河南郑州450006 郑州市第二人民医院神经内科河南郑州450006 郑州市第二人民医院疾病控制科河南郑州450006

目的探讨高压氧综合治疗老年急性脑梗死患者人类软骨糖蛋白39(YKL-40)、血管内皮生长因子(VEGF)动态变化及其与预后的相关性。方法选取2019年1月至2022年12月郑州市第二人民医院神经内科收治的老年急性脑梗死患者51例,依据患者的治疗... 详细信息

目的探讨高压氧综合治疗老年急性脑梗死患者人类软骨糖蛋白39(YKL-40)、血管内皮生长因子(VEGF)动态变化及其与预后的相关性。方法选取2019年1月至2022年12月郑州市第二人民医院神经内科收治的老年急性脑梗死患者51例,依据患者的治疗方式分为对照组23例,高压氧治疗组28例,对照组接受溶栓、营养神经、改善脑部循环、抗自由基等治疗;高压氧组则在常规治疗的基础上行高压氧治疗,舱压0.2 MPa,每日1次,10次为1个疗程,治疗2个疗程。分别于入院第1天和治疗后,观察并分析两组患者的美国国立卫生研究院卒中量表,并观察高压氧综合治疗对不同时间(入院第1、4、7、14天)血清YKL-40、VEGF动态变化水平和预后相关性分析。结果对照组、高压氧组血清YKL-40水平随着病程进展呈动态变化,于发病第4天达峰值,第7天出现下降(P<0.05),高压氧组低于对照组(P<0.05),VEGF水平随着病程进展逐渐升高,于发病第7天达峰值(P<0.05),高压氧组高于对照组(P<0.05)。高压氧组好转患者多于未好转者,好转组发病第4、7天血清YKL-40水平低于未好转组(P<0.05),血清VEGF治疗第4、7天高于未好转组(P<0.05)。相关分析示血清YKL-40水平与脑梗死患者近期预后呈负相关(P<0.05),血清VEGF与脑梗死患者近期预后呈正相关(P<0.05)。二元logistic回归分析结果显示:高压氧治疗后VEGF(β=0.033,P=0.045)、YKL-40(β=-0.098,P=0.025)与老年脑梗死患者预后独立相关。结论高压氧治疗可有效改善脑梗死患者神经功能缺失,减轻患者机体炎症反应,YKL-40水平可以作为评价高压氧综合治疗后脑梗死患者病情和判断预后的指标。

关键词：高压氧急性脑梗死人类软骨糖蛋白39 血管内皮生长因子

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药学研究 2024年第4期43卷 313-318,337页

作者：杨钒石清兰柏文婕毛德文封佩佩杨敏陶向君黄乾铭潘佩佩广西中医药大学广西南宁530200 广西中医药大学第一附属医院广西南宁530023

目的观察解毒化瘀退黄方对乙肝相关中国肝癌分期(CNLC)Ⅳ期湿热瘀阻证患者的临床疗效及安全性。方法选取2021年1月至2022年6月于我院肝病科确诊为乙肝相关CNLCⅣ期湿热瘀阻证患者72例,随机分为对照组、观察组,每组36例;对照组采用西医治... 详细信息

目的观察解毒化瘀退黄方对乙肝相关中国肝癌分期(CNLC)Ⅳ期湿热瘀阻证患者的临床疗效及安全性。方法选取2021年1月至2022年6月于我院肝病科确诊为乙肝相关CNLCⅣ期湿热瘀阻证患者72例,随机分为对照组、观察组,每组36例;对照组采用西医治疗,观察组给予西医治疗+解毒化瘀退黄方口服,疗程均为12周,随访24周。比较两组治疗前及治疗4、12周后肿瘤大小、肿瘤个数、中医证候积分、细胞因子、肿瘤标志物、生化指标、Child-Pugh分级评分、体力及功能状态评分、患者生存率。结果治疗4周后,观察组瘤体大小较对照组增长缓慢,观察组的临床证候积分、白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、甲胎蛋白(AFP)、甲胎蛋白异质体-L3(AFP-L3)、总胆红素(TBIL)、凝血酶原时间(PT)、Child-Pugh分级较对照组降低且ALB较对照组升高,观察组KPS较对照组降低延缓;治疗12周后,观察组瘤体大小及个数较对照组增长缓慢,观察组的临床证候积分、肿瘤坏死因子α(TNF-α)、IL-1β、IL-6、AFP、AFP-L3、异常凝血酶原(DCP)、谷丙转氨酶(ALT)、谷草转氨酶(AST)、TBIL、PT、Child-Pugh分级均较对照组降低且白蛋白(ALB)较对照组升高,观察组KPS较对照组降低延缓,ZPS较对照组升高较慢;观察组较之对照组的临床疗效及生存率较高。结论解毒化瘀退黄方能抑制乙肝相关CNLCⅣ期湿热瘀阻证患者的肿瘤增长,降低中医证候积分、TNF-α、IL-1β、IL-6、AFP、AFP-L3、DCP、ALT、AST、TBIL、PT、Child-Pugh分级评分水平,改善肝功能,延缓体力及功能状态的恶化,明显提高乙肝相关CNLCⅣ期湿热瘀阻证患者的临床疗效及带瘤生存质量。

关键词：解毒化瘀退黄方中国肝癌分期Ⅳ期炎症介质临床疗效

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An improved RRT algorithm for mobile robot path planning

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An improved RRT algorithm for mobile robot path planning

第32届中国过程控制会议(CPCC2021)

作者： wenjie bai Xinchun Jia Teng Lv School of Mathematical Sciences Shanxi University School of Automation and Software Engineering Shanxi University

Aiming at the problems of traditional Rapidly-exploring Random Trees(RRT) in mobile robot path planning,such as low node utilization,redundant turning points,long and unsmooth path,an improved RRT algorithm(Improved RRT,I-RRT) is *** I-RRT first uses a dynamic step size strategy based on probability division and an angle constraint strategy to determine the new ***,an ant colony optimization algorithm(Ant Colony Optimization,ACO) is utilized to optimize the generated path from both length and smoothness ***,an improved piecewise B-spline path smoother is introduced to smooth the path at the *** simulation results show that,compared with the traditional RRT algorithm,the I-RRT algorithm has a higher planning efficiency,can obtain a shorter length of the planned path,the generated path is smoother,and is verified to be feasible and effective.

关键词： Path planning RRT dynamic step size angle constraint piecewise B-spline

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星群协同阵列传输容量

北京航空航天大学学报 2015年第9期41卷 1615-1623页

作者：肖振宇李瑶白文杰白琳北京航空航天大学电子信息工程学院北京100191 北京航空航天大学高等工程学院北京100191

为进一步提升星群协同的系统容量,考虑在卫星星群上配置阵列天线的传输模式.分析了最大化容量时下行链路的信道条件,给出了系统容量最大化的实现方式,探索了系统参数对信道容量的影响,发现信道容量随地面天线间距成周期性变化,其周期与... 详细信息

为进一步提升星群协同的系统容量,考虑在卫星星群上配置阵列天线的传输模式.分析了最大化容量时下行链路的信道条件,给出了系统容量最大化的实现方式,探索了系统参数对信道容量的影响,发现信道容量随地面天线间距成周期性变化,其周期与卫星数目成反比、与地面天线阵列相对于东西方向的夹角的余弦成反比、与相邻卫星之间的角间距成反比.在多卫星多天线环境下,发现信道容量曲线的包络同样随地面天线间距成周期性变化,提出并通过仿真验证了多卫星多天线环境下减小地面天线间距和降低测控精确度要求的地面天线排布方案.

关键词：阵列天线星群协同信道容量多入多出卫星信道模型

Consensus of Multi-Agent Systems with a multi-rate sampling mechanism under deception attacks

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Consensus of Multi-Agent Systems with a multi-rate sampling ...