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多参量在线反馈的大型筒体-端框精确对装方法
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作者 刘海波 李猛 +3 位作者 王新 王永青 马玉勇 李兰柱 《宇航学报》 EI CAS CSCD 北大核心 2015年第12期1459-1463,共5页
针对几何尺寸大、结构刚度小、误差终端累积效应显著等制造特征引起的大型筒体-端框对接装配问题,提出一种基于过程参量在线反馈的精确对装新方法,设计筒体和端框的圆跳动、对装缝隙等多参量同步在线测量方案,研制多传感组合测量装置,... 针对几何尺寸大、结构刚度小、误差终端累积效应显著等制造特征引起的大型筒体-端框对接装配问题,提出一种基于过程参量在线反馈的精确对装新方法,设计筒体和端框的圆跳动、对装缝隙等多参量同步在线测量方案,研制多传感组合测量装置,并将其集成于对装系统,从而优化对装工艺,提高对装效率和精度稳定性。经检测,采用所提出的方法,大尺寸复合材料筒体与铝合金端框对装缝隙误差可有效控制在0.15 mm范围内,满足对装精度要求,验证了所研制的多参量在线测量系统对提高对装精度的有效性。 展开更多
关键词 多参量 在线测量 筒体-端框 精确对装
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分体式转炉托圈的对装组焊方法
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作者 朱小波 《机械工程师》 2015年第3期246-247,共2页
针对大中型分体式转炉托圈现场对装组焊的施工问题进行研究分析,提出了一套安全可靠的对装和组焊方法,通过该方法的实施,提高了产品质量和生产效率。
关键词 转炉 托圈 对装 组焊
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大型工件与水平轴对装的导向工装设计
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作者 申亮 《冶金设备管理与维修》 2022年第1期62-63,共2页
设计了用于大型工件与水平轴对装的导向工装,解决了现场条件受限、大型轴承等工件与水平轴对装如何保证对中安装到位的技术难题。
关键词 对装 设计
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谈间接对接装卸应产生的效益
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作者 张广民 《铁道运输与经济》 北大核心 2001年第6期44-45,共2页
针对火车与汽车、船舶对装对卸货物时 ,间接对装对卸的作业量比直接对装对卸的作业量大 ,但收费标准却一样的不合理问题 ,建议尽快对《铁路货物装卸作业计费办法》进行补充、修订 ,将应收的费用收回来。
关键词 间接对装对卸 收费 铁路 货物 计费办法
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白光LED封装工艺对其性能的影响 被引量:3
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作者 郑毅夫 《现代显示》 2008年第3期60-63,共4页
通过理论分析与实验数据说明了白光LED封装工艺对其性能的影响,特别针对模粒卡位、胶体外形等进行较为详细的分析。
关键词 对装工艺 白光LED 材料
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连南板洞电站压力钢管安装
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作者 张华 《金属结构》 2000年第4期69-72,共4页
本文从施工的角度以连南板洞电站压力钢管安装为例阐述了水电站压力钢管安装过程中对装、焊接、超声波检验的一般原则,特别针对现场地形,对首装节的安装和弯管的修改作了具体的技术介绍。
关键词 对装 焊接 超声波检验 节安 弯管修改 水电站 压力钢管
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超大型弧门制造焊接质量控制 被引量:1
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作者 刘剑 《水力发电》 北大核心 2005年第6期45-47,50,共4页
洪江电站超大型弧形闸门焊缝较多,焊接变形较大、焊接变形控制困难。闸门制作中,利用多种焊接变形控制技术,对闸门制造全过程焊接进行了跟踪和研究。通过采用预留收缩余量和反变形量,钢性加固,合理选择焊接方法,调整焊接顺序等措施保障... 洪江电站超大型弧形闸门焊缝较多,焊接变形较大、焊接变形控制困难。闸门制作中,利用多种焊接变形控制技术,对闸门制造全过程焊接进行了跟踪和研究。通过采用预留收缩余量和反变形量,钢性加固,合理选择焊接方法,调整焊接顺序等措施保障了产品焊接最终质量。该闸门制造焊接质量控制经验可供借鉴。 展开更多
关键词 超大型弧门 焊接 对装 变形 控制 制造
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龙头石电站泄洪洞工作闸门主梁制作技术
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作者 孙文 刘成君 《焊接技术》 北大核心 2008年第5期37-41,共5页
简要介绍了龙头石2#泄洪洞超大型工作弧门变截面主梁制作技术,结合实际生产经验,通过采取电脑放样、排料、数控下料及制定合理的对装工艺和焊接工艺等措施,成功地完成了制作任务,并有效地控制了主梁成型的几何尺寸,满足了设计要求。本... 简要介绍了龙头石2#泄洪洞超大型工作弧门变截面主梁制作技术,结合实际生产经验,通过采取电脑放样、排料、数控下料及制定合理的对装工艺和焊接工艺等措施,成功地完成了制作任务,并有效地控制了主梁成型的几何尺寸,满足了设计要求。本文的阐述和总结为同类结构复杂、焊接量大的焊接件生产积累了丰富的经验,具有实际借鉴意义。 展开更多
关键词 超大型弧门主梁 对装工艺 焊接工艺
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超大型弧门焊接质量控制措施
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作者 刘剑 《焊接技术》 2004年第5期47-49,共3页
洪江电站超大型弧形闸门焊缝多、焊接变形大、焊接变形控制困难。对该闸门制造的关键部件的焊接质量控制和关键工序质量控制方法作了具体阐述。
关键词 超大型弧门 焊接 对装 收缩 变形 控制
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90t特钢钢包结构及制作方法改进
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作者 王盛 《山东冶金》 CAS 2020年第2期71-72,共2页
为满足生产需要,增强钢包承载力及结构强度,莱钢特钢对90 t钢包进行结构设计。对钢包对装工艺、焊接工艺两方面进行了优化,优化后,钢包在外观方面及承载力和强度方面都显著增强,提高了90 t钢包的实用性,延长了钢包的使用寿命,形成了生产... 为满足生产需要,增强钢包承载力及结构强度,莱钢特钢对90 t钢包进行结构设计。对钢包对装工艺、焊接工艺两方面进行了优化,优化后,钢包在外观方面及承载力和强度方面都显著增强,提高了90 t钢包的实用性,延长了钢包的使用寿命,形成了生产90 t钢包的系统的工作流程,提高了制作效率,缩短了制作周期。 展开更多
关键词 钢包 对装工艺 焊接工艺 使用寿命
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向家坝右岸坝后电站蜗壳制作过程控制
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作者 蒋伯林 《四川水利》 2022年第5期104-106,126,共4页
向家坝水电站坝后电站共设置3台机组,每台机组均由34节蜗壳组成,蜗壳的加工制作质量是后续各项工作顺利开展的前提。文章就蜗壳在实际生产过程中的质量分析、瓦片卷制与对装控制、焊接变形控制等几个方面进行了分析,并提出了相关措施,... 向家坝水电站坝后电站共设置3台机组,每台机组均由34节蜗壳组成,蜗壳的加工制作质量是后续各项工作顺利开展的前提。文章就蜗壳在实际生产过程中的质量分析、瓦片卷制与对装控制、焊接变形控制等几个方面进行了分析,并提出了相关措施,经检验验收证明了制作过程控制方案和有关措施是可行有效的,为后期同类产品加工提供了借鉴经验。 展开更多
关键词 蜗壳 瓦片卷制 焊前对装 支架 焊接变形控制
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Characterizing Thermal Augmentation of Convection-Enhanced Drug Delivery with the Fiberoptic Microneedle Device 被引量:2
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作者 R.Lyle Hood Rudy T.Andriani +2 位作者 Tobias E.Ecker John L.Robertson Christopher G.Rylander 《Engineering》 SCIE EI 2015年第3期344-350,共7页
Convection-enhanced delivery (CED) is a promising technique leveraging pressure-driven flow to increase penetration of infused drugs into interstitial spaces. We have developed a fiberoptic microneedle device for in... Convection-enhanced delivery (CED) is a promising technique leveraging pressure-driven flow to increase penetration of infused drugs into interstitial spaces. We have developed a fiberoptic microneedle device for inducing local sub-lethal hyperthermia to further improve CED drug distribution volumes, and this study seeks to quantitatively characterize this approach in agarose tissue phantoms. Infusions of dye were conducted in 0.6% (w/w) agarose tissue phantoms with isothermal conditions at 15 ℃, 20℃, 25 ℃, and 30 ℃. Infusion metrics were quantified using a custom shadowgraphy setup and image- processing algorithm. These data were used to build an empirical predictive temporal model of distribution volume as a function of phantom temperature. A second set of proof- of-concept experiments was conducted to evaluate a novel fiberoptic device capable of generating local photothermal heating during fluid infusion. The isothermal infusions showed a positive correlation between temperature and distribution volume, with the volume at 30℃ showing a 7-fold increase at 100 min over the 15 ℃ isothermal case. Infusions during photothermal heating (1064 nm at 500 mW) showed a similar effect with a 3.5-fold increase at 4 h over the control (0 mW). These results and analyses serve to provide insight into and characterization of heat-mediated enhancement of volumetric dispersal. 展开更多
关键词 near-infrared laser THERMOCHEMOTHERAPY AGAROSE photothermal heating micro-catheter malignant glioma
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The Soret and Dufour Effects in Non-thermal Equilibrium Packed Beds with Forced Convection and Endothermic Reactions* 被引量:1
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作者 李明春 赵中亮 +2 位作者 静宇 刘家涛 吴玉胜 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第8期867-875,共9页
To study the influence of the Soret and Dufour effects on the reactive characteristics of a porous packed bed with endothermic reactions and forced convection, a two-dimensional mathematical model considering the cros... To study the influence of the Soret and Dufour effects on the reactive characteristics of a porous packed bed with endothermic reactions and forced convection, a two-dimensional mathematical model considering the cross-diffusion effects was developed in accordance with the thermodynamics of irreversible processes and the local thermal non-equilibrium model. The simulation results were validated by comparing with experimental data. The influence of the Soret and Dufour effects on the heat transfer, mass transfer and endothermic chemical reaction in the non-thermal equilibrium packed bed is discussed. It was found that when the Peclet number reaches 1865, the maximum relative error of the concentration of gas product induced by the Soret effect is 34.7% and that of the solid fractional conversion caused by the Dufour effect is 10.8% at reaction time 160 s and initial temperature 1473 K. The differences induced by the Soret and Dufour effects are demonstrated numerically to increase gradually with the initial temperature of feeding gas and the Peclet number. 展开更多
关键词 heat and mass transfer thermal decomposition cross-diffusion effects porous packed bed
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Development of cooperative system bridges
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作者 张哲 万其柏 《Journal of Chongqing University》 CAS 2008年第3期198-205,共8页
Cooperative system bridges comprise several basic structures that act jointly to improve structural characteristics. We delved into the historical development of cooperative system bridges. Cooperative systems are cla... Cooperative system bridges comprise several basic structures that act jointly to improve structural characteristics. We delved into the historical development of cooperative system bridges. Cooperative systems are classified as different-load cooperative systems and same-load cooperative systems by distinguishing the modes of load distribution. For different-load cooperation,individual basic structures are at different positions in the direction along bridge axis and carry the loads separately. While for same-load cooperation,all basic structures overlap in geometrical locations and support the entire loads conjointly. The choosing of span ratios between basic structures,the design of connections of different-load cooperative systems were discussed as well as optimizations of relative rigidity for same-load cooperative systems which greatly influence structural characteristics. The general situation and several structural measurements of several cooperative bridges were demonstrated. This information can assist engineers in developing their concepts in cooperative systems and can lead to more efficient and economical cooperative bridges. 展开更多
关键词 cooperative system different-load cooperation same-load cooperation connection relative rigidity
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Venous thromboembolism prophylaxis in hospitalized elderly patients: Time to consider a 'MUST' strategy 被引量:6
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作者 Kwok M Ho Edward Litton 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2011年第2期114-120,共7页
Venous thromboembolism (VTE) is the commonest cause of preventable death in hospitalized patients. Elderly patients have higher risk of VTE because of the high prevalence of predisposing co-morbidities and acute ill... Venous thromboembolism (VTE) is the commonest cause of preventable death in hospitalized patients. Elderly patients have higher risk of VTE because of the high prevalence of predisposing co-morbidities and acute illnesses. Clinical diagnosis of VTE in the elderly patient is particularly difficult and, as such, adequate VTE prophylaxis is of pivotal importance in reducing the mortality and morbidities of VTE. Omission of VTE prophylaxis is, however, very common despite continuous education. A simple way to overcome this problem is to implement universal VTE prophylaxis for all hospitalized elderly patients instead of selective prophylaxis for some patients only according to individual' s risk of VTE. Although pharmacological VTE prophylaxis is effective for most patients, a high prevalence of renal impairment and drug interactions in the hospitalized elderly patients suggests that a multimodality approach may be more appropriate. Mechanical VTE prophylaxis, including calf and thigh compression devices and/or an inferior vena cava filter, are often underutilized in hospitalized elderly patients who are at high-risk of bleeding and VTE. Because pneumatic compression devices and thigh length stockings are virtually risk free, mechanical VTE prophylaxis may allow early or immediate implementation of VTE prophylaxis for all hospitalized elderly patients, regardless of their bleeding and VTE risk. Although the cost-effectiveness of this Multimodality Universal STat ('MUST') VTE prophylaxis approach for hospitalized elderly patients remains uncertain, this strategy appears to offer some advantages over the traditional 'selective and single-modal' VTE prophylaxis approach, which often becomes 'hit or miss' or not implemented promptly in many hospitalized elderly patients. A large clustered randomized controlled trial is, however, needed to assess whether early, multimodality, universal VTE prophylaxis can improve important clinical outcomes of hospitalized elderly patients. 展开更多
关键词 age bundle of care deep vein thrombosis PREVENTION pulmonary embolism
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Effective Thermal Conductivity with Convection and Radiation in Packed Bed 被引量:1
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作者 Yusuke Asakuma Tsuyoshi Yamamoto 《Journal of Energy and Power Engineering》 2013年第4期639-646,共8页
Effective thermal conductivity with convection and radiation is analyzed by the homogenization method. This method can precisely represent the microstructure of a packed bed. In this study, the effects of parameters s... Effective thermal conductivity with convection and radiation is analyzed by the homogenization method. This method can precisely represent the microstructure of a packed bed. In this study, the effects of parameters such as the radiation emissivity, temperature, contact area and particle size of the packed bed on the conductivity have been estimated. For example, heat transfer by radiation does not dominate if the material has voids of less than l mm in size. Moreover, the effects of contact area and pressure on effective thermal conductivity are negligible for thermal radiation. By considering the microscopic behavior of a packed bed, the homogenization method is thus a powerful tool for estimating the bed's effective thermal conductivity. 展开更多
关键词 Effective thermal conductivity homogenization method multiscale analysis MICROSTRUCTURE thermal radiation.
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An iris recognition method based on multi-orientation features and Non-symmetrical SVM 被引量:1
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作者 古红英 庄越挺 潘云鹤 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第5期428-432,共5页
A new iris feature extraction approach using both spatial and frequency domain is presented. Steerable pyramid is adopted to get the orientation information on iris images. The feature sequence is extracted on each su... A new iris feature extraction approach using both spatial and frequency domain is presented. Steerable pyramid is adopted to get the orientation information on iris images. The feature sequence is extracted on each sub-image and used to train Support Vector Machine (SVM) as iris classifiers. SVM has drawn great interest recently as one of the best classifiers in machine learning, although there is a problem in the use of traditional SVM for iris recognition. It cannot treat False Accept and False Reject differently with different security requirements. Therefore, a new kind of SVM called Non-symmetrical SVM is presented to classify the iris features. Experimental data shows that Non-symmetrical SVM can satisfy various security requirements in iris recognition applications. Feature sequence combined with spatial and frequency domain represents the variation details of the iris patterns properly. The results in this study demonstrate the potential of our new approach, and show that it performs more satis- factorily when compared to former algorithms. 展开更多
关键词 Iris recognition Steerable pyramid Variation fractal dimension Non-symmetrical Support Vector Machine (NSVM)
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Research on La Chapelle's "seamless" full channel sales model
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作者 HE Zongping 《International English Education Research》 2017年第1期1-3,共3页
The essence of the whole channel is customer satisfaction, the pursuit of customer experience, this is the ultimate goal. With the side of the mobile phone shopping boom intensified, with high-tech fusion of fashion r... The essence of the whole channel is customer satisfaction, the pursuit of customer experience, this is the ultimate goal. With the side of the mobile phone shopping boom intensified, with high-tech fusion of fashion retailers also join the flay, demonstrating its ability to satisfy the consumers at any time and place, shopping demand, thus officially announced the full channel retail era. La Chapelle is a clothing enterprise sales in Intemet plus the tide of the times, combined with the characteristics of innovation, a new sales model, namely "seamless" full channel sales model. Through the whole channel: business combination of traditional business model, the whole direct: online and offline synchronization services, new competition: the O2O model provides a three-dimensional three-dimensional services constitute the innovation. This paper mainly introduces La Chapelle's full channel mode analysis to get the full channel mode successfully, and implicit in the crisis enterprise development of this mode, at the same time, several companies to address the challenges of decision-making is also introduced, finally is a summary. 展开更多
关键词 La Chapelle Full channel sales model Innovation O2O model
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Disguisable Symmetric Encryption Schemes for an Anti-forensics Purpose
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作者 Ding Ning Gu Dawu Liu Zhiqiang 《China Communications》 SCIE CSCD 2010年第6期56-63,共8页
In this paper, we propose a new notion of secure disguisable symmetric encryption schemes, which captures the idea that the attacker can decrypt an encrypted fie to different meaningful values when different keys are ... In this paper, we propose a new notion of secure disguisable symmetric encryption schemes, which captures the idea that the attacker can decrypt an encrypted fie to different meaningful values when different keys are put to the decryption algorithm. This notion is aimed for the following anti-forensics purpose: the attacker can cheat the forensics investigator by decrypting an encrypted file to a meaningful file other than that one he encrypted, in the case that he is caught by the forensics investigator and ordered to hand over the key for decryption. We then present a construction of secure disguisable symmetric encryption schemes. 展开更多
关键词 symmetric encryption OBFUSCATION ANTI-FORENSICS
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Realization of Relative Humidity Scale Using NIS Two-Temperature Humidity Generator
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作者 Mohamed Gamal Ahmed Said Mazen +1 位作者 Doaa Abd El-Gelil Nabila Ismail El Sayed 《Journal of Physical Science and Application》 2014年第8期484-487,共4页
A new humidity calibration facility using a 2-T (two-temperature), constant pressure principle for generating gas of known humidity has been developed at NIS for primary realization of relative humidity scale in the... A new humidity calibration facility using a 2-T (two-temperature), constant pressure principle for generating gas of known humidity has been developed at NIS for primary realization of relative humidity scale in the range from 13% to 98% for calibrating and testing hygrometers to improve the uncertainty. This paper reports the construction of the 2-T humidity generator describing its saturator and the test chamber system. Results of the efficiency tests of its saturator showed satisfactory generation performance for a primary realization of relative humidity scale. The expanded uncertainty of the relative humidity with a coverage factor k = 2 was found to be from ± 0.25 % to ± 0.67%. 展开更多
关键词 Calibration relative humidity GENERATOR SATURATOR uncertainty.
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