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1.
电力保护装置在出厂前要进行严格的板卡测试,传统板卡测试系统自动化程度较低,功能不够强大,且开发成本高,通用性不好。针对以上不足,设计了一种基于虚拟仪器的板卡测试系统,该系统主要由测试程序和上位机两部分组成,测试程序主要完成对板卡设备的模块化测试,并给出测试结果;上位机通过以太网与测试板卡通信,借助FTP和telnet技术,完成整个测试程序的发送、执行、测试结果的获取等功能。以电力保护装置内的CPU板卡为研究对象,结果表明,该测试系统可对板卡进行高效率自动测试,测试结果可靠,故障信息可追踪,可有效提高电力保护装置调试的通过率,保证企业产品的可靠性。  相似文献   
2.
倪敬达 《纺织学报》2022,43(8):7-11
针对新型高产梳棉机采用顺向给棉方式生产细绒棉产品,梳棉机产量不高、刺辊区落棉率高、除杂效果不够理想、生条和成纱质量指标不佳等问题,通过分析顺向给棉和逆向给棉的优缺点,并在同型号梳棉机上分别采用顺向给棉和逆向给棉2种形式进行梳棉,对比给棉方式对高产梳棉机刺辊梳理效果的影响,验证了给棉方式对高产梳棉机纺精梳纯棉纱和普梳纯棉色纺纱的影响。结果表明:逆向给棉方式可提高梳棉机产量,提高给棉与刺辊之间的分梳能力,降低落棉率,提高落棉含杂率,减轻锡林周围主分梳区的分梳、除杂负担,提高生条和成纱质量,提高梳理器材的使用寿命,尤其对生产以细绒棉为原料的本色纱和色纺纱具有优势。  相似文献   
3.
针对传统技术在识别低压台区拓扑关系时存在用户相位识别精度和接入表箱识别精度低的问题,研究了基于改进数据驱动模型的低压台区拓扑关系自动识别技术。从历史用电数据中采集低压台区用户的电压数据,在标准化处理后得到电压矩阵方程式;在初始化纠错参数的基础上,通过求解用户关系方程得到低压台区配电器与用户间的关系,通过关系校验组建低压台区拓扑关系的识别方程式,结合差值向量的取值范围完成纠错处理;利用改进数据驱动模型求得二次规划模型的矩阵,并构建低压台区拓扑关系识别模型。实验结果表明,该技术可以提高用户相位识别精度和接入表箱识别精度,证明其具有更好的识别性能。  相似文献   
4.
针对国内外锌冶炼行业技术发展现状,以北矿机电科技有限责任公司研制的新一代大极板自动剥锌机组为研究对象,首先介绍了大极板自动剥锌机组基本结构与工作流程,然后对阴极板自动装卸机构进行结构设计和工作过程分析,解决了进口剥锌机需要人工辅助钩板的弊端,实现了阴极板自动装卸彻底无人化操作,大幅提高了剥锌效率和设备的安全性可靠性,具有重要的工程应用指导意义。  相似文献   
5.
周超  赵静  王晓东  卢建峰  曹宇航 《焊管》2022,45(5):48-51
为了解决钢管防腐生产过程中人工贴纸质量不稳定、岗位员工劳动强度大等问题,设计出一种钢管防腐管端自动贴纸装置。该装置由贴纸机头、三坐标线性滑动平台、自动控制系统组成,通过伺服控制系统,执行钢管管端自动贴纸作业。现场使用效果表明,该设备具有钢管管端自动贴纸功能,且结构简单,操作方便,贴纸质量稳定,纸张搭接处平整,可适用于钢管外表面防腐生产线,能够提升贴纸工作效率和工艺精度,完全可取代钢管防腐生产过程中传统人工贴纸方式。  相似文献   
6.
《Journal of dairy science》2022,105(2):1661-1673
The objective of this study was to evaluate how meal patterns of recently weaned and group-housed dairy calves are subject to effects of previous dietary experience and associated with competition for feed. During the preweaning period, Holstein heifer and bull calves were provided diets differing in provision and presentation of forage as follows: (1) pelleted starter only (n = 12), (2) starter and chopped coastal bermudagrass provided in separate buckets (n = 13), (3) starter and chopped coastal bermudagrass mixed together in the same bucket (n = 15), or (4) starter, chopped coastal bermudagrass, and liquid molasses mixed together in 1 bucket (n = 13). At 58 ± 2 (mean ± standard deviation) days of age, following weaning, calves were mingled between treatments and moved into group housing in weekly age-based cohorts (7 ± 2 calves/group; 8 groups total), and all were provided the mixed diet (without molasses). Within group pens, calves were fed individually using the Calan Broadbent feeding system (American Calan Inc.). Calves were monitored for 1 wk following introduction to the group pen. Feed intake was measured daily. Behavioral data, describing feeding times and competition for feed, were recorded continuously for 48 h beginning after a 5-d adaptation to the group pen. Calves previously provided starter only had longer, less frequent meals than calves previously provided forage in any form, and they tended to consume less feed compared with those previously provided starter and hay separately, with calves previously provided mixed diets having intermediate intakes. We observed occurrences of displacements at bins, which were followed by replacements and feed stealing on some occasions, where 34% of calves consumed feed from a bin assigned to another calf on at least 1 occurrence, and 64% of calves were stolen from at least once. Competition at feed bins was not affected by previous dietary treatments, but was associated with meal patterns. Actor displacement rate was negatively associated with meal frequency and duration, but calves that were displaced more often were those that spent more time feeding. These results suggested a possible carryover effect of previous exposure to forage on postweaning meal patterns following a dietary change. Further, we found that competitive behavior varied considerably between individuals, occurring frequently despite feeding calves using individually-assigned feeding bins, and was associated with meal characteristics. These results highlighted the importance of considering both previous dietary experience and social factors when evaluating feeding behavior.  相似文献   
7.
《Journal of dairy science》2022,105(10):8130-8142
Residual feed intake (RFI) is a measurement of the difference between actual and predicted feed intake when adjusted for energy sinks; more efficient cows eat less than predicted (low RFI) and inefficient cows eat more than predicted (high RFI). Data evaluating the relationship between RFI and feeding behaviors (FB) are limited in dairy cattle; therefore, the objective of this study was to determine daily and temporal FB in mid-lactation Holstein cows across a range of RFI values. Mid-lactation Holstein cows (n = 592 multiparous; 304 primiparous) were enrolled in 17 cohorts at 97 ± 26 d in milk (± standard deviation), and all cows within a cohort were fed a common diet using automated feeding bins. Cow RFI was calculated as the difference between predicted and observed dry matter intake (DMI) after accounting for parity, days in milk, milk energy, metabolic body weight and change, and experiment. The associations between RFI and FB at the level of meals and daily totals were evaluated using mixed models with the fixed effect of RFI and the random effects of cow and cohort. Daily temporal FB analyses were conducted using 2-h blocks and analyzed using mixed models with the fixed effects of RFI, time, RFI × time, and cohort, and the random effect of cow (cohort). There was a positive linear association between RFI and DMI in multiparous cows and a positive quadratic relationship in primiparous cows, where the rate of increase in DMI was less at higher RFI. Eating rate, DMI per meal, and size of the largest daily meal were positively associated with RFI. Daily temporal analysis of FB revealed an interaction between RFI and time for eating rate in multiparous and primiparous cows. The eating rate increased with greater RFI at 11 of 12 time points throughout the day, and eating rate differed across RFI between multiple time points. There tended to be an interaction between RFI and time for eating time and bin visits in multiparous cows but not primiparous cows. Overall, there was a time effect for all FB variables, where DMI, eating time and rate, and bin visits were greatest after the initial daily feeding at 1200 h, increased slightly after each milking, and reached a nadir at 0600 h (6 h before feeding). Considering the relationship between RFI and eating rate, additional efforts to determine cost-effective methods of quantifying eating rate in group-housed dairy cows is warranted. Further investigation is also warranted to determine if management strategies to alter FB, especially eating rate, can be effective in increasing feed efficiency in lactating dairy cattle.  相似文献   
8.
为了高效地利用风能和雨能,设计了通过压电传感器组件a将风或雨的能量转换为电能的装置。该装置可为负载和蓄电池供电,它的分辨力高,即使是弱风和小雨产生的微压也能进行电能转换。当压电晶体板d或e受压时,小齿轮顺时针或逆时针旋转;当压电晶体b或c受压时,液压缸伸长或收缩。在液压缸和小齿轮的作用下,压电晶体板a所在平面的法线自动调整到正好与风和雨的方向一致,从而增大了电能转化率。  相似文献   
9.
罗运良  李井双  王旭 《焊管》2022,45(8):31-34,39
针对某海上风电导管架吸力桶管径大、筒壁厚且立式建造导致的焊接工作量较大的问题,采用埋弧自动横焊焊接工艺,通过坡口设计、焊接工艺参数的合理选择,克服了横焊埋弧焊焊接过程中铁水下垂、层间未熔合、焊剂敷洒等操作难点,实现了埋弧横焊在吸力桶环缝的应用。风电导管架吸力桶埋弧自动横焊的焊接工艺试验结果显示,焊缝外观、硬度、力学性能均符合相关标准要求。该工艺的应用表明,吸力桶环缝焊接作业效率得到大幅提升,并且节约了人工成本。  相似文献   
10.
为了研究自动化固定测斜仪在地下连续墙深层水平位移监测的可行性,布设了1 m间距的自动化测孔孔1与0.5 m测量的人工孔CX8,通过对自动化测孔与人工测孔数据的对比分析及现场施工工况匹配分析,发现自动化监测单个传感器数据从孔口到孔底呈现先负、再负正、再全为正的整体规律,测点最大水平累计位移一直在开挖面附近达到最大。人工监测和自动化监测深层水平累计位移曲线均能及时、准确地反映出各种工况条件下引起的基坑水平位移。说明自动化监测能较好地反映深层水平位移的变形情况,进而验证了固定测斜仪在基坑深层水平位移监测中的可行性。  相似文献   
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