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Evaluation of non-azeotropic mixtures containing HFOs as potential refrigerants in refrigeration and high-temperature heat pump systems

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Science China(Technological Sciences) 2010年第7期53卷 1855-1861页

作者： ZHANG ShengJun, WANG huaixin & GUO Tao Department of Thermal Energy and Refrigeration Engineering, Tianjin University, Tianjin 300072, China Department of Thermal Energy and Refrigeration Engineering Tianjin University Tianjin China

With the increasing environmental concern on global warming, hydrofluoro-olefin (HFOs), possessing low GWP, has attracted great attention of many researchers recently. In this study, non-azeotropic mixtures composed of HFOs (HFO-1234yf, HFO-1234ze(z), HFO-1234ze(e) and HFO-1234zf) are developed to substitute for HFC-134a and CFC-114 in air-conditioning and high-temperature heat pump systems, respectively. The cycle performances were evaluated by an improved theoretical cy-cle evaluation methodology. The results showed that all the mixtures proposed herein were favorable refrigerants with excel-lent thermodynamic cycle performances. M1A presented lower discharge temperature and pressure ratio and higher COPc than that of HFC-134a. The volumetric cooling capacity was similar to HFC-134a. It can be served as a good environmentally friendly alternative to replace HFC-134a. M3H delivered similar discharge temperature as CFC-114 did. And the COPh was 3% higher. It exhibits excellent cycle performance in high-temperature heat pump and is a promising refrigerant to substitute for CFC-114. And the gliding temperature differences enable them to exhibit better coefficient of performance by matching the sink/source temperature in practice. Because the toxicity, flammability and other properties are not investigated in detail, ex-tensive toxicity and flammability testing needs to be conducted before they are used in a particular application.

关键词： hydrofluoro-olefin non-azeotropic mixtures refrigerant air-conditioning system high-temperature heat pump

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超声滚压对铝合金表面完整性的影响

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天津职业技术师范大学学报 2024年第2期34卷 1-9页

作者：李隆思靳刚张丹丹王光余林怀鑫马元浩天津职业技术师范大学机械工程学院天津300222

在对铝合金6061进行平面超声滚压加工的基础上,设计了基于进给方向和主轴旋转方向、静压力、滚压次数的试验,分别从硬度、表面粗糙度、表面形貌和残余应力4个方面开展了不同的加工工艺和加工参数对铝合金6061表面性能的影响研究。结果表... 详细信息

在对铝合金6061进行平面超声滚压加工的基础上,设计了基于进给方向和主轴旋转方向、静压力、滚压次数的试验,分别从硬度、表面粗糙度、表面形貌和残余应力4个方面开展了不同的加工工艺和加工参数对铝合金6061表面性能的影响研究。结果表明:进给方向和主轴旋转方向对硬度的影响随着方向的改变呈现增加的趋势,材料表面硬度随着静压力的增加而增加,随着滚压次数的增加先增大后减小;与相同方向和上下方向进给滚压相比,从4个方向进给滚压可以获得较小的表面粗糙度值(0.554μm),不同主轴旋转方向粗糙度低于相同旋转方向,表面粗糙度随静压力和滚压次数的增加均呈现先减小后增大的趋势;与未滚压相比,超声滚压后工件的表面形貌轮廓曲线及表面三维形貌得到明显改善;超声滚压处理使工件表面的残余拉应力转变为残余压应力,并且进给方向不同时工件残余应力(-441.5 MPa)大于相同方向进给时的残余应力(-362.6 MPa);主轴旋转方向不同时工件残余应力(-435.6 MPa)大于相同方向的残余应力(-362.6 MPa);残余应力随着静压力和滚压次数的增加而增加,过量的滚压次数使材料表面产生疲劳失效,导致残余应力降低。

关键词：超声滚压进给方向主轴旋转方向表面完整性

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Vehicle Ego-Localization Based on Streetscape Image Database Under Blind Area of Global Positioning System

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Journal of Shanghai Jiaotong university(Science) 2019年第1期24卷 122-129页

作者： ZHOU Jingmei ZHAO Xiangmo CHENG Xin XU Zhigang ZHAO huaixin School of Electronic and Control Engineering Chang'an University School of Information Engineering Chang'an University

Vehicle positioning is critical for inter-vehicle communication, navigation, vehicle monitoring and tracking. They are regarded as the core technology ensuring safety in everyday-driving. This paper proposes an enhanced vehicle ego-localization method based on streetscape image database. It is most useful in the global positioning system(GPS) blind area. Firstly, a database is built by collecting streetscape images, extracting dominant color feature and detecting speeded up robust feature(SURF) points. Secondly, an image that the vehicle shoots at one point is analyzed to find a matching image in the database by dynamic programming(DP)matching. According to the image similarity, several images with higher probabilities are selected to realize coarse positioning. Finally, different weights are set to the coordinates of the shooting location with the maximum similarity and its 8 neighborhoods according to the number of matching points, and then interpolating calculation is applied to complete accurate positioning. Experimental results show that the accuracy of this study is less than 1.5 m and its running time is about 3.6 s. These are basically in line with the practical need. The described system has an advantage of low cost, high reliability and strong resistance to signal interference, so it has a better practical value as compared with visual odometry(VO) and radio frequency identification(RFID) based approach for vehicle positioning in the case of GPS not working.

关键词： vehicle ego-localization global positioning system(GPS) blind area dominant color dynamic programming(DP) matching weighted interpolation

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Electronic modulation and structure engineered MoSe2 with multichannel paths as an advanced anode for sodium-ion half/full batteries

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Science China Materials 2022年第11期65卷 2997-3006页

作者： Chengkui Lv Chunfa Lin Huilong Dong huaixin Wei Jun yang Hongbo Geng School of Chemistry and Life Sciences Suzhou University of Science and TechnologySuzhou 215009China School of Materials Engineering Changshu Institute of TechnologyChangshu 215500China School of Material Science&Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Owing to the abundance and low price of sodium,researches on sodium-ion batteries(SIBs)as a lithiumion battery(LIB)alternative are emerging as a *** is crucial to develop electrode materials suitable for sodium *** recent years,two-dimensional(2 D)layered transition metal disulfide compounds(TMDs)have trigered interest in the realm of energy and environmental *** particular,MoSeis thought to be a suitable material for SIBs due to its wide original layer spacing and high ***,N-doped dual carbon-coated MoSewith multichannel paths(MoSe/multichannel carbon nanofibers(MCFs)@NC)is fabricated via electrospinning,followed by a selenation and carbonization *** existence of a 3 D conductive network,abundant void spaces,and sufficient electron transportation pathways are conducive to rapid and fast charge transfer kinetics under volume expansion *** applied in SIBs,the MoSe/MCFs@NC shows a high capability(319 mA hg^(-1)at 10 A g^(-1)),as well as good cycling stability(303 mA h g^(-1)after 1100 cycles at 10 A g^(-1)).Furthermore,coupled with the Na_(3)V_(2)(PO_(4))_(2)O_(2)F cathode,the full cell also exhibits excellent *** theoretical calculation of the MoSe_(2)/MCFs@NC confirms that the superiority of its SIB performance is owing to the strong interaction between the double-doped carbon and *** scheme provides a wide space for preparing high-performance electrode materials for SIBs.

关键词： dual carbon-coated multichannel paths sodium-ion batteries full batteries theoretical calculation

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集成学习在水产品无机砷含量预测中的应用研究

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职业与健康 2024年第7期40卷 913-916,922页

作者：梁怀新王润东王浩然刘斌郑存芳秦皇岛市疾病预防控制中心理化检验科河北秦皇岛066000 河北港口集团港口医院检验科河北秦皇岛066000 燕山大学电气工程学院河北秦皇岛066044

目的水产品中无机砷元素慢性暴露严重危害人体健康,其检测时间成本较高,为实现无机砷元素含量快速预测,构建一种基于小样本特征量的无机砷元素含量预测集成学习模型。方法抽取2018—2022年秦皇岛地区水产品重金属元素检测数据,采用皮尔... 详细信息

目的水产品中无机砷元素慢性暴露严重危害人体健康,其检测时间成本较高,为实现无机砷元素含量快速预测,构建一种基于小样本特征量的无机砷元素含量预测集成学习模型。方法抽取2018—2022年秦皇岛地区水产品重金属元素检测数据,采用皮尔逊法对铅、镉、汞、无机砷4种元素做相关性分析并检验多重共线性。使用逐步回归向量组合法测试不同特征组合下梯度提升回归树(gradient boosting regressor,GBR)和随机森林模型(random forest,RF)的拟合优度(R^(2))及均方误差(mean squared error,MSE),以筛选最优组合。综合比对5种集成学习算法在模型评估指标、预测误差比率分布、目标危险系数(target hazard quotients,THQ)三方面的预测效果以评估方法可行性。结果4种重金属元素间呈弱相关,不存在多重共线性。RF及GBR算法拟合优度R^(2)分别为89.9%、93.3%。极端学习树模型(extremely randomized tree,ET)在贝、鱼、蟹、虾类水产品中R^(2)分别为100.00%、99.42%、100.00%、99.92%,且箱式图中预测误差的偏差均最小,异常值在可接受范围内,预测前后膳食风险评估THQ结果均为安全水平。结论本研究提出的方法针对小样本量及特征量的无机砷元素快速预测,可为食品安全风险预警提供一种低成本、高效的预测技术方法。

关键词：无机砷回归预测水产品小样本

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A Distributed Compressed Sensing for Images Based on Block Measurements Data Fusion

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Journal of Software Engineering and Applications 2012年第12期5卷 134-139页

作者： huaixin Chen Jie Liu Key Lab. of Information Processing Southwest China Institute of Electronics Technology Chengdu P.R. China

Compressed sensing (CS) is a new technique for simultaneous data sampling and compression. In this paper, we propose a novel method called distributed compressed sensing for image using block measurements data fusion. Firstly, original image is divided into small blocks and each block is sampled independently using the same measurement operator, to obtain the smaller encoded sparser coefficients and stored measurements matrix and its vectors.? Secondly, original image is reconstructed using the block measurements fusion and recovery transform. Finally, several numerical experiments demonstrate that our method has a much lower data storage and calculation cost as well as high quality of reconstruction when compared with other existing schemes. We believe it is of great practical potentials in the network communication as well as pattern recognition domain.

关键词： distributed CS for image information fusion pattern recognition network communication

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Hilbert空间中的Bessel序列(英文)

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工程数学学报 2000年第2期17卷 92-98页

作者：曹怀信陕西师范大学数学系西安710062

研究了 Hilbert空间 H中的 Bessel序列 ,应用算子论方法给出了这种序列成为 H中的框架、紧框架、独立框架、Risez基、正规正交基的条件 ;建立了这些序列与 H到 l2中的相应算子之间的对应关系与构造这些序列的统一方法。

关键词： Hilbert空间 Bessel序列 Risez基正规正交基

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Refinement of four major QTL for oil content in Brassica napus by integration of genome resequencing and transcriptomics

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The Crop Journal 2022年第3期10卷 627-637页

作者： Shuxiang Yan huaixin Li Hongbo Chao Jianjie He Yiran Ding Weiguo Zhao Kai Zhang Yiyi Xiong Kang Chen Libin Zhang Maoteng Li Department of Biotechnology College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074HubeiChina Key Laboratory of Molecular Biophysics of the Ministry of Education Wuhan 430074HubeiChina School of Agricultural Sciences Zhengzhou UniversityZhengzhou 450001HenanChina

Rapeseed(Brassica napus)supplies about half of the vegetable oil in *** oil production and searching for genes that control oil content in the crop are research *** our previous studies,four major QTL for oil content located on A08,A09,C03 and C06 in the Ken C-8×N53-2(KN DH)mapping population were *** parental lines were resequenced to identify structural variations and candidate genes affecting oil content in these four major QTL ***-deletion(In Del)markers were developed and used to narrow the *** expressed genes located in the regions were *** and KEGG analysis showed that several genes were associated with lipid *** transcription factors with higher expression in N53-2 than in Ken C-8 were *** results shed light on the genetic control of oil content and may be helpful for the development of highoil-content cultivars.

关键词： Brassica napus Oil content QTL mapping Resequencing Transcriptome

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面向可持续发展的墨西哥教育改革

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拉丁美洲研究 2005年第6期27卷 57-59页

作者：祝怀新杨慧浙江大学西溪校区教育系

墨西哥是拉美地区开展可持续发展教育较为出色的国家,本文从分析墨西哥开展教育改革的背景资料入手,分五个方面概括介绍了墨西哥以可持续发展为核心的教育理念,并进一步总结了墨西哥开展面向可持续发展教育的最为突出的几个策略,以期对... 详细信息

墨西哥是拉美地区开展可持续发展教育较为出色的国家,本文从分析墨西哥开展教育改革的背景资料入手,分五个方面概括介绍了墨西哥以可持续发展为核心的教育理念,并进一步总结了墨西哥开展面向可持续发展教育的最为突出的几个策略,以期对中国可持续发展教育的实施提供有益的借鉴。

关键词：墨西哥可持续发展环境教育

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英国教师教育策略探析——基于对大学与中小学伙伴关系的认识

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全球教育展望 2005年第3期34卷 44-47,59页

作者：杨慧祝怀新浙江大学教育学院博士浙江杭州310028 浙江大学教育系副教授博士浙江杭州310028

促进教师的专业化发展是当前国际教师教育改革的重大趋势,英国职前教师教育的一大特色,就是通过建立大学和中小学校之间的伙伴美系,进行了卓有成效的初始教师专业化发展,从而确保大学教育类学生能够顺利入职。本文从英国伙伴关系实施的... 详细信息

促进教师的专业化发展是当前国际教师教育改革的重大趋势,英国职前教师教育的一大特色,就是通过建立大学和中小学校之间的伙伴美系,进行了卓有成效的初始教师专业化发展,从而确保大学教育类学生能够顺利入职。本文从英国伙伴关系实施的背景、伙伴关系的形成和发展过程、实施现状等几个方面作了介析,并对此进行了反思,以期对我国教师教育改革提供有效的借鉴。

关键词：教师教育改革大学教育中小学校职前教师教师专业化发展伙伴关系英国形成和发展探析实施现状

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