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Fujitsu MB87M3550 WiMAX解决方案
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《世界电子元器件》 2008年第1期40-41,共2页
Fujitsu WiMAX SoC参考套件是通过WiMAX论坛认证的产品开发的基础。利用Fujitsu MB87M3550 SoC的功能和灵活性,参考套件为产品开发人员配备了设计环境,从而测试WiMAX设计。
关键词 FUJITSU WIMAX 产品开发 设计环境 人员配备 SOC 套件
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高密度集成电路封装基板微缺陷检测方法研究
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作者 王建荣 马万里 +3 位作者 黄渊 葛飞虎 廖忠智 宣慧 《中国集成电路》 2025年第5期64-69,共6页
由于易受遮蔽、噪声及光照变化等外部因素的干扰,封装基板表面纹理复杂,微缺陷往往与背景噪声难以区分,且受制于成像设备的精度限制,缺陷边缘信息易被模糊化,导致传统检测方法在特征提取与分类阶段难以准确区分前景与背景,降低了检测结... 由于易受遮蔽、噪声及光照变化等外部因素的干扰,封装基板表面纹理复杂,微缺陷往往与背景噪声难以区分,且受制于成像设备的精度限制,缺陷边缘信息易被模糊化,导致传统检测方法在特征提取与分类阶段难以准确区分前景与背景,降低了检测结果的准确性。因此,提出高密度集成电路封装基板微缺陷检测方法。通过均值滤波平滑处理、形态学膨胀操作以及设计纹理算子等方法,对高密度集成电路封装基板图像数据进行系统化处理,抑制噪声并凸显微缺陷。采用图像二值化处理、能量区划分与特征熵计算、离散余弦变换等技术,从处理后的图像中提取清晰的前景与背景界定、缺陷的形状特征以及细节特征。在缺陷检测阶段,采用基于形状的模板匹配方法,应对遮蔽、噪声以及光照变化等外部因素的干扰,针对微小且难以准确检测的缺陷样本,在损失函数中融入Focal Loss策略,实现对高密度集成电路封装基板微缺陷的精准检测。实验结果表明,研究方法能够在高密度集成电路封装基板微缺陷检测中显著提高缺陷定位精度和缺陷检测灵敏度,从而提高了缺陷检测的准确性。 展开更多
关键词 高密度集成电路 封装基板 特征提取 微缺陷 缺陷检测
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尿素热解制氨SCR脱硝技术在电厂的应用 被引量:1
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作者 谷志国 刘艳平 《山西化工》 CAS 2024年第11期207-208,216,共3页
尿素热解制氨选择性催化还原(SCR)脱硝技术是一种在电厂中用于降低氮氧化物(NO_(x))排放的有效方法。本研究旨在探讨该技术在电厂中的应用,并评估其对环境和能源方面的影响。文章介绍尿素热解制氨SCR脱硝技术的基本原理,详细描述了该技... 尿素热解制氨选择性催化还原(SCR)脱硝技术是一种在电厂中用于降低氮氧化物(NO_(x))排放的有效方法。本研究旨在探讨该技术在电厂中的应用,并评估其对环境和能源方面的影响。文章介绍尿素热解制氨SCR脱硝技术的基本原理,详细描述了该技术在电厂中的应用情况,进一步评估该技术对环境和能源方面的影响。结果显示,尿素热解制氨SCR脱硝技术可有效降低NO_(x)排放,减少大气污染。此外,该技术的能源消耗相对较低,对电厂运行成本的影响较小。未来的研究可进一步优化催化剂的设计和制备方法,以提高SCR脱硝技术的稳定性。 展开更多
关键词 尿素热解制氨 SCR脱硝 电厂 应用研究
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静脉识别技术专利情报实证分析 被引量:1
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作者 商琦 周皓怡 《科技管理研究》 CSSCI 北大核心 2018年第20期188-194,共7页
利用Orbit专利信息检索数据库和incoPat分析工具,对全球静脉识别技术专利情报进行检索策略、申请趋势、技术应用区域和创新机构竞争态势分析,尤其对核心专利进行深度挖掘,为国内相关研发提供参考。分析结果表明,静脉识别技术领域的研究... 利用Orbit专利信息检索数据库和incoPat分析工具,对全球静脉识别技术专利情报进行检索策略、申请趋势、技术应用区域和创新机构竞争态势分析,尤其对核心专利进行深度挖掘,为国内相关研发提供参考。分析结果表明,静脉识别技术领域的研究热点集中于手指静脉认证系统改进和静脉图像特征识别领域,日本和韩国在该技术领域的研发实力较强,各自拥有独特的核心专利。中国虽然在该技术领域专利申请量最大,但核心专利较少,核心创新能力有待提高。 展开更多
关键词 静脉识别 实证分析 热点 核心专利
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载钛羟基磷灰石对水中EE2光催化降解规律及途径研究 被引量:1
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作者 鞠传伦 张健伟 +3 位作者 孙卫玲 若村正人 塚田峰春 佐佐正名 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2018年第4期815-827,共13页
以17α-乙炔雌二醇(EE2)为目标污染物,以载钛羟基磷灰石(TiHAP)为催化剂,对比研究TiHAP和TiO_2对EE2的光催化规律、影响因素及机理,分析光催化降解的中间产物及降解途径。实验结果表明,TiHAP薄膜对EE2的降解速率高于TiO_2薄膜;随着Fe^(... 以17α-乙炔雌二醇(EE2)为目标污染物,以载钛羟基磷灰石(TiHAP)为催化剂,对比研究TiHAP和TiO_2对EE2的光催化规律、影响因素及机理,分析光催化降解的中间产物及降解途径。实验结果表明,TiHAP薄膜对EE2的降解速率高于TiO_2薄膜;随着Fe^(3+)浓度增加,TiHAP降解EE2的速率没有明显变化,TiO_2降解EE2的速率则先增加后减小;随着富里酸(FA)浓度的增加,TiHAP降解EE2的速率减小,而TiO_2降解EE2的速率升高。用LC-MSn对TiHAP光催化降解EE2过程中产生的中间产物进行分析,在中性pH条件下共确定9种降解产物,比同样pH值下以TiO_2为催化剂检出的产物种类多,推断其降解的主要途径是苯环羟基化、开环羧基化以及脱羧等一系列反应。 展开更多
关键词 载钛羟基磷灰石 17α-乙炔雌二醇 光催化降解
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联合自编码任务的多机制融合复述生成模型
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作者 刘明童 张玉洁 +3 位作者 张姝 孟遥 徐金安 陈钰枫 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2020年第1期53-60,共8页
基于神经网络编码–解码框架的复述生成模型存在两方面的问题:1)生成的复述句中存在实体词不准确、未登录词和词汇重复生成;2)复述平行语料的有限规模限制了编码器的语义学习能力。针对第一个问题,本文提出在解码过程中融合注意力机制... 基于神经网络编码–解码框架的复述生成模型存在两方面的问题:1)生成的复述句中存在实体词不准确、未登录词和词汇重复生成;2)复述平行语料的有限规模限制了编码器的语义学习能力。针对第一个问题,本文提出在解码过程中融合注意力机制、复制机制和覆盖机制的多机制复述生成模型,利用复制机制从原句复制词语来解决实体词和未登录词生成问题;利用覆盖机制建模学习注意力机制的历史决策信息来规避词汇重复生成。针对第二个问题,基于多任务学习框架,提出在复述生成任务中联合自编码任务,两个任务共享一个编码器,同时利用平行复述语料和原句子数据,共同增强复述生成编码器的语义学习能力。在Quora复述数据集上的实验结果表明,提出的联合自编码的多机制融合复述生成模型有效地解决了复述生成的问题,并提高了复述句的生成质量。 展开更多
关键词 复述生成 自编码 多任务学习 多机制融合 注意力机制 复制机制 覆盖机制
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SDN Orchestration for Dynamic End-to-End Control of Data Center Multi-Domain Optical Networking 被引量:3
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作者 LIU Lei 《China Communications》 SCIE CSCD 2015年第8期10-21,共12页
New and emerging use cases, such as the interconnection of geographically distributed data centers(DCs), are drawing attention to the requirement for dynamic end-to-end service provisioning, spanning multiple and hete... New and emerging use cases, such as the interconnection of geographically distributed data centers(DCs), are drawing attention to the requirement for dynamic end-to-end service provisioning, spanning multiple and heterogeneous optical network domains. This heterogeneity is, not only due to the diverse data transmission and switching technologies, but also due to the different options of control plane techniques. In light of this, the problem of heterogeneous control plane interworking needs to be solved, and in particular, the solution must address the specific issues of multi-domain networks, such as limited domain topology visibility, given the scalability and confidentiality constraints. In this article, some of the recent activities regarding the Software-Defined Networking(SDN) orchestration are reviewed to address such a multi-domain control plane interworking problem. Specifically, three different models, including the single SDN controller model, multiple SDN controllers in mesh, and multiple SDN controllers in a hierarchical setting, are presented for the DC interconnection network with multiple SDN/Open Flow domains or multiple Open Flow/Generalized Multi-Protocol Label Switching( GMPLS) heterogeneous domains. I n addition, two concrete implementations of the orchestration architectures are detailed, showing the overall feasibility and procedures of SDN orchestration for the end-to-endservice provisioning in multi-domain data center optical networks. 展开更多
关键词 software-defined networking(SDN) generalized multi-protocol labelswitching (GMPLS) path computationelement (PCE) data center ORCHESTRATION multi-domain optical network
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A New Experimental Rig of Testing Flow Boiling Heat Transfer of Refrigerantand Lubricant Mixture 被引量:5
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作者 魏文建 丁国良 王凯建 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期62-67,共6页
This paper proposed a new experimental rig of testing flow boiling heat transfer of refrigerant and lubricant oil mixture. The quantity of oil in the test section can be controlled and regulated conveniently and accur... This paper proposed a new experimental rig of testing flow boiling heat transfer of refrigerant and lubricant oil mixture. The quantity of oil in the test section can be controlled and regulated conveniently and accurately by connecting separate lubricant oil circuit with test section in parallel. It was built up by retrofitting a multiple air-conditioner and installing three oil-separators in serials at the compressor outlet. And so the lubricant oil in the discharged refrigerant gas of compressor can be removed completely.The refrigerant flow rate through test section can be bypassed by the by-path circuit of indoor unit.This experimental rig has advantages such as on-line and continuous oil injection, short time of obtaining stability, flexible operation, simple control, which lead to high efficiency in the research of flow boiling heat transfer of refrigerant and lubricant oil mixture. 展开更多
关键词 REFRIGERANT flow boiling heat transfer lubricant oil
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Gene expression profiles of hepatic cell-type specific marker genes in progression of liver fibrosis 被引量:5
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作者 Yoshiyuki Takahara Mitsuo Takahashi +5 位作者 Hiroki Wagatsuma Fumihiko Yokoya Qing-Wei Zhang Mutsuyo Yamaguchi Hiroyuki Aburatani Norifumi Kawada 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第40期6473-6499,共27页
AIM: To determine the gene expression profile data for the whole liver during development of dimethylni-trosamine (DMN)-induced hepatic fibrosis.METHODS: Marker genes were identified for different types of hepatic cel... AIM: To determine the gene expression profile data for the whole liver during development of dimethylni-trosamine (DMN)-induced hepatic fibrosis.METHODS: Marker genes were identified for different types of hepatic cells, including hepatic stellate cells (HSCs), Kupffer cells (including other inflammatory cells), and hepatocytes, using independent temporal DNA microarray data obtained from isolated hepatic cells. RESULTS: The cell-type analysis of gene expression gave several key results and led to formation of three hypotheses: (1) changes in the expression of HSC-specific marker genes during fibrosis were similar to gene expression data in in vitro cultured HSCs, suggesting a major role of the self-activating characteristics of HSCs in formation of fibrosis; (2) expression of mast cell-specific marker genes reached a peak during liver fibrosis, suggesting a possible role of mast cells in formation of fibrosis; and (3) abnormal expression of hepatocyte-specific marker genes was found across several metabolic pathways during fibrosis, including sulfur-containing amino acid metabolism, fatty acid metabolism, and drug metabolism, suggesting a mechanistic relationship between these abnormalities and symptoms of liver fibrosis. CONCLUSION: Analysis of marker genes for specific hepatic cell types can identify the key aspects of fibro-genesis. Sequential activation of inflammatory cells and the self-supporting properties of HSCs play an important role in development of fibrosis. 展开更多
关键词 Liver fibrosis Gene expression Microarray DIMETHYLNITROSAMINE Marker genes Hepatic stellate cell Kupffer cell HEPATOCYTES Metabolic pathway
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Resource Allocation and Beamforming Algorithm Based on Interference Avoidance Approach for Device-to-Device Communication Underlaying LTE Cellular Network 被引量:2
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作者 Huy-Dung Han Chenxi Zhu +1 位作者 Dorin Viorel Akira Ito 《Communications and Network》 2013年第3期367-373,共7页
In this work, we consider device-to-device (D2D) direct communication underlaying a 3GPP LTE-A network. D2D communication enables new service opportunities, provides high throughput and reliable communication while re... In this work, we consider device-to-device (D2D) direct communication underlaying a 3GPP LTE-A network. D2D communication enables new service opportunities, provides high throughput and reliable communication while reducing the base station load. For better total performance, D2D links and cellular links share the same radio resource and the management of interference becomes a crucial task. We propose a radio resource allocation for D2D links based on interference avoidance approach. For system with multiple transmit antennas, we apply beamforming technique based on signal to leakage criterion to reduce the co-channel interference. The results show that, D2D transmission with the resource allocation and beamforming technique provides significant gain compared to that of the regular cellular network. 展开更多
关键词 Device-to-Device LTE RESOURCE ALLOCATION BEAMFORMING
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A Dynamic Object Behavior Model and Implementation Based on Computational Reflection 被引量:1
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作者 HE Cheng-wan HE Fei HE Ke-qing 《Wuhan University Journal of Natural Sciences》 CAS 2005年第2期358-362,共5页
A dynamic object behavior model based on computational reflection is proposed.This model consists of function level and meta level,the meta objects in meta level manage the base objects and behaviors in function level... A dynamic object behavior model based on computational reflection is proposed.This model consists of function level and meta level,the meta objects in meta level manage the base objects and behaviors in function level,including dynamic binding and unbinding of base object and behavior.We implement this model with RoleJava Language,which is our self linguistic extension of the Java Language.Meta Objects are generated automatically at compile\|time,this makes the reflecton mechanism transparent to programmers.Finally an example applying this model to a banking system is presented. 展开更多
关键词 dynamic object behavior role computational reflection MOP(meta object protocol)
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基于NB-IoT的物联网应用研究 被引量:5
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作者 林长勇 《信息与电脑》 2017年第17期167-168,171,共3页
随着物联网技术的发展,整个社会正经历着一场数字化变革,万物移动互联(包括人物互联以及物物相连)产生巨量的数据并进一步影响到人类社会生活的各个方面,基于大数据和物联网融合的应用也在生产和生活中逐步得到大规模使用。电信运营商... 随着物联网技术的发展,整个社会正经历着一场数字化变革,万物移动互联(包括人物互联以及物物相连)产生巨量的数据并进一步影响到人类社会生活的各个方面,基于大数据和物联网融合的应用也在生产和生活中逐步得到大规模使用。电信运营商在物联网生态中占据重要的位置,是底层基础设施的提供者,其所主导的NB-IoT技术在低功耗广域网领域具有诸多优势,包括低功耗、覆盖广、低成本、大连接、可靠安全等,可应用在公共事业、智慧建筑、智慧城市、工业自动化等领域。笔者重点介绍基于NB-IoT的物联网应用,并对相关趋势进行分析和研究。 展开更多
关键词 物联网 NB-IoT 低功耗 广域网
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Feasible Method to Assess the Performance of a Lung Cancer CT Screening CAD System in Clinical Practice: Dependence on Nodule Size and Density 被引量:1
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作者 Janaka C. Marasinghe Masaki Ohkubo +4 位作者 Hajime Kobayashi Kohei Murao Toru Matsumoto Shusuke Sone Shinichi Wada 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2014年第2期107-116,共10页
Detection of small pulmonary nodules is the goal of lung cancer screening. Computer-aided detection (CAD) systems are recommended to use in lung cancer computed tomography (CT) screening to increase the accuracy of no... Detection of small pulmonary nodules is the goal of lung cancer screening. Computer-aided detection (CAD) systems are recommended to use in lung cancer computed tomography (CT) screening to increase the accuracy of nodule detection. Size and density of lung nodules are primary factors in determining the risk of malignancy. Therefore, purpose of this study is to apply computer-simulated virtual nodules based on the point spread function (PSF) measured in same scanner (maintaining spatial resolution condition) to assess the CAD system performance dependence on nodule size and density. Virtual nodules with density differences between lung background and nodule density (ΔCT) values (200, 300 and 400 HU) and different sizes (4 to 8 mm) were generated and fused on clinical images. CAD detection was performed and free-response receiver operating characteristic (FROC) curves were obtained. Results show that both density and size of virtual nodules can affect detection efficiency. Detailed results are possible to use for quantitative analysis of a CAD system performance. This study suggests that PSF-based virtual nodules could be effectively used to assess the lung cancer CT screening CAD system performance dependence on nodule size and density. 展开更多
关键词 COMPUTED Tomography (CT) Point SPREAD Function (PSF) Lung Cancer Screening COMPUTER-AIDED Detection (CAD) Virtual NODULE
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基于客户满意度评价的软件项目群团队构建 被引量:1
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作者 李惠 《数字技术与应用》 2020年第11期208-211,共4页
软件企业一直追求合理利用人力资源实现利益最大化,但是受制于软件项目多、人员核心技术能力参差不齐等客观条件而往往很难实现利益最大化。客户满意度评价是企业利益的一种表现形式。通过总结客户满意度评价的影响因素和指标,构建评价... 软件企业一直追求合理利用人力资源实现利益最大化,但是受制于软件项目多、人员核心技术能力参差不齐等客观条件而往往很难实现利益最大化。客户满意度评价是企业利益的一种表现形式。通过总结客户满意度评价的影响因素和指标,构建评价预测模型,并利用运筹优化方法求解最佳软件项目群团队构建方式,可以在有限的人力资源条件下实现最大利益。 展开更多
关键词 客户满意度 软件项目群 预测 运筹优化
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Design and Evaluation of CRDMAC: Circular RTR Directional MAC Protocol for WANETs
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作者 Lu Huang Li Jie +1 位作者 Dong Zhongping Ji Yusheng 《China Communications》 SCIE CSCD 2012年第6期1-13,共13页
Using directional antennas in Wireless Ad hoc Networks (WANETs) offers great potential of reducing the radio interference, and improving the communication throughput. Directional antennas, however, introduces new prob... Using directional antennas in Wireless Ad hoc Networks (WANETs) offers great potential of reducing the radio interference, and improving the communication throughput. Directional antennas, however, introduces new problems in the wireless Media Access Control (MAC), that is, the deafness and new hidden terminal problem, which may cause severe performance degradation. To solve the problems, we propose an effective Circular RTR Directional MAC (CRDMAC) protocol for WANETs by using a sub-transmission channel and Ready to Receive (RTR) packets, which modifies the IEEE 802.11 Distributed Coordinated Function (DCF). The sub-channel avoids collisions to other ongoing transmission, and the RTR packets notify the neighbor nodes that the mutual transmission has been finished. We evaluate the CRDMAC protocol through simulations and the results show that the proposed protocol outperforms existing DMAC (directional MAC) protocol and the CRCM (Circular RTS and CTS MAC) protocol in terms of throughput and packet drop rate. 展开更多
关键词 WANETs MAC protocol directionalantenna DEAFNESS new hidden terminal
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Object detection based on combination of local and spatial information
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作者 Qinkun Xiao Nan Zhang +1 位作者 Fei Li Yue Gao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期715-720,共6页
A method of object detection based on combination of local and spatial information is proposed. Firstly, the categorygiven representative images are chosen through clustering to be templates, and the local and spatial... A method of object detection based on combination of local and spatial information is proposed. Firstly, the categorygiven representative images are chosen through clustering to be templates, and the local and spatial information of template are ex- tracted and generalized as the template feature. At the same time, the codebook dictionary of local contour is also built up. Secondly, based on the codebook dictionary, sliding-window mechanism and the vote algorithm are used to select initial candidate object win- dows. Lastly, the final object windows are got from initial candidate windows based on local and spatial structure feature matching. Experimental results demonstrate that the proposed approach is able to consistently identify and accurately detect the objects with better performance than the existing methods. 展开更多
关键词 object detection codebook dictionary spatial matching local contour matching.
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Correlations of Two-phase Friction of Refrigerant in Horizontal Smooth Tube with 2.5 mm inside Diameter
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作者 魏文建 丁国良 王凯建 《Journal of Donghua University(English Edition)》 EI CAS 2006年第1期78-83,共6页
Two-phase flow pressure drop measurements are made during phase change heat transfer process of R-22 in small horizontal smooth tubes with 2.5 mm inside diameter. Conclusions are drawn that the quality corresponding t... Two-phase flow pressure drop measurements are made during phase change heat transfer process of R-22 in small horizontal smooth tubes with 2.5 mm inside diameter. Conclusions are drawn that the quality corresponding to pressure gradient peak value of small tubes became higher than that of large tubes and that effects of quality on pressure drop become weak as the increase of mass flux. The experiment data are compared with predicted values of the state-of-the-art correlations from the open literature, which indicates that most of the state-of-the-art correlations fail to predict the present experimental data. Chisholm model shows a relatively better predictive ability than the other empirical correlations because it has the lowest mean deviation of 26.7%. But the predicted values of Chisholm model are 50% lower than experimental data when quality becomes higher. In this regard, an new empirical correlation based on Chisholm model is developed and this modified Chisholm correlation can describe 95% of the present data with ±20% mean deviations. 展开更多
关键词 REFRIGERANT flow boiling pressure drop performance small tube
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FPGA结合DAC实现直接中频
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作者 Paul Maddox 《电子产品世界》 2003年第07B期49-49,62,共2页
关键词 DAC技术 FPGA 数/模转换器 中频 CMOS 转换速率 直接 新一代 高速 性能
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如何设计安全、有效的信号继电器
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作者 Noboru Fujii Hirofumi Saso 《电子产品世界》 2003年第09B期31-32,共2页
关键词 设计安全 信号继电器 调制解调器 绝缘性能 结构设计
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A Metamodel-Driven Business Process Modeling Methodology and Its Integrated Environment for Reusing Business Processes
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作者 Rieko Yamamoto Kouji Yamamoto +2 位作者 Kyoko Ohashi Junji Inomata Mikio Aoyama 《Journal of Software Engineering and Applications》 2018年第8期363-382,共20页
Reusing business process models and best practices can improve the productivity, quality and agility in the early development phases of enterprise software systems. To help developers reuse the business process models... Reusing business process models and best practices can improve the productivity, quality and agility in the early development phases of enterprise software systems. To help developers reuse the business process models and best practices, we propose a methodology and an integrated environment for business process modeling driven by the metamodel. Furthermore, we propose a process-template design method to unify the granularity and separate the commonality and variability of business processes so that business process models can be reused across different enterprise software systems. The proposed methodology enables to create reuse-oriented business process templates before the business process modeling. To support the proposed methodology, we developed an integrated environment for creating, reusing and verifying the business process models. As the key techniques, we describe the methodology and its integrated environment, including a metamodel and notations. We applied the methodology and integrated environment to an actual enterprise software development project, and evaluated that the productivity of business process modeling is improved by at least 46%. As the conclusion, this paper contributes to prove the effectiveness of the meta-model driven business process modeling methodology for the reuse of business process models. 展开更多
关键词 ENTERPRISE Software Development BUSINESS PROCESS Modeling BUSINESS PROCESS METAMODEL UML REUSABLE BUSINESS PROCESS Model Integrated Environment
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