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1.
宋建  王宇峰  梁家睿  李东 《科学技术与工程》2022,22(27):12000-12005
针对注塑生产过程中人工质量检测存在的效率低、成本高等问题,提出了一种基于注塑加工过程数据对产品尺寸是否合格进行预测判定的方法,首先对于清洗后的数据集采用5折交叉验证筛选出LR模型、SVM模型等5个分类模型,然后以ROC曲线和AUC值作为性能评估指标,综合比较和分析了5个分类模型在不同特征选取方法下的分类性能。结果表明:基于树模型特征选取与LR算法组合对本文的数据集表现出优良的分类性能,准确率可达96.42%,具有一定的工程应用价值。  相似文献   

2.
刘萍 《科技信息》2010,(18):I0304-I0304
本文论述了水泥安定性这一指标对混凝土性能的重要影响。利用试验室的试验数据,证实了水泥安定性不合格对工程质量的重大危害,并介绍了在施工过程中判定水泥安定性是否合格的简易方法。  相似文献   

3.
丁爱梅  辛娟娟 《科技信息》2010,(21):J0229-J0229
钢筋混凝土试验是检验结构物质量的依据,是判定结构是否合格得依据。现阶段试验人员建设工程质量管理条例中有关产品质量监督检验及检测机构质量管理体系的条款;公路水运工程试验检测管理办法第四章中涉及检测机构和检测人员的条款;公路水运工程试验检测机构等级认定中现场评审的主要内容;检测标准的分类及使用原则。  相似文献   

4.
钻具产品的性能检测非常重要和严格,较为关键的是其性能的判定.以多属性决策理论为基础,针对钻具产品性能判定复杂且准确率较低的问题,提出了实用的性能判定的方法.实践表明,该性能判定方法可行.利用该方法可以提高钻具及相关产品的使用效率以及企业对产品的总体管理水平.  相似文献   

5.
姜红 《科技资讯》2012,(13):108+110-108,110
煤质化验数据关系到生产产品的品质是否合格,煤质化验工作,尤其是煤质化验结果的准确性就显得尤为重要。本文分析了煤质化验误差来源,进行了煤质化验误差的判定,提出了煤质化验误差控制和数据分析方法。  相似文献   

6.
龙昭航  谢锋  陈芳  王艳娇 《贵州科学》2012,30(6):77-78,84
酸价是判断植物油是否酸败的一个主要质量指标。文章采用目视法判定食用植物油中酸价是否合格,并用国家标准检验方法进行对比验证。该方法简便、快速、准确,同时检测试剂用量少,可实现现场检测,提高检测效率。  相似文献   

7.
在工程建设过程中,桩基检测工程内容繁多,各种检测方法交叉运用,桩基检测方法作为评价桩基是否合格的重要依据,也对桩基补救具有重要意义,本文主要针对桩基检测主要内容和常用方法浅谈自已的观点。  相似文献   

8.
目前对驾驶员进行是否酒驾的接触式、非实时的随机抽检方式已难以满足酒驾检测的实际需求.在加速行驶路段、匀速行驶路段、转弯路段等典型城市道路下,以车辆速度、加速度和油门踏板位置、发动机转速等交通参数为输入,采用支持向量机模型对驾驶员的驾驶行为进行识别并判定其是否处于酒驾状态,并采用粒子群优化算法对模型参数进行优化以提高训练速度.研究结果表明,基于粒子群优化算法的支持向量机模型能快速、准确地判定驾驶员是否处于酒驾状态,可为实现非接触式酒驾检测提供理论支持,为安全驾驶辅助系统采取相应措施提供实现基础.  相似文献   

9.
在电冰箱生产中,需要对冷藏室、冷冻室、压缩机进气口、出气口和环境温度等参数进行检测,以判定电冰箱是否合格.DS18B20直接输出相应温度的数字量,无须变送电路和AD转换器,使用极其方便,已被电冰箱生产厂家广泛采用.文章设计了一个DS18B20温度传感器校验平台;由于Pt100温度测量存在系统误差、随机误差和粗大误差,为...  相似文献   

10.
郭进 《广东科技》2003,(10):44-44
一 概述 在电工电子产品认证中,材料性能是否合格将直接关系到用户使用该产品的安全性,所以对材料性能进行考查的材料试验是非常重要的。灼热丝试验是考查材料防火性能的一个重要试验项目,它是利用模拟技术评定由于灼热元件或过载电阻之类的热源在短时间  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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