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Development of a cloud condensation nuclei (CCN) counter using a laser and charge-coupled device (CCD

Mikyung PARK, Jinkwan OH, Kihong PARK

《环境科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 313-319 doi: 10.1007/s11783-011-0346-y

摘要： A continuous flow streamwise thermal gradient cloud condensation nuclei (CCN) counter with an aerosol focusing and a laser-charge-coupled device (CCD) camera detector system was developed here. The counting performance of the laser-CCD camera detector system was evaluated by comparing its measured number concentrations with those measured with a condensation particle counter (CPC) using polystyrene latex (PSL) and NaCl particles of varying sizes. The CCD camera parameters (e.g. brightness, gain, gamma, and exposure time) were optimized to detect moving particles in the sensing volume and to provide the best image to count them. The CCN counter worked well in the particle number concentration range of 0.6–8000 #·cm and the minimum detectable size was found to be 0.5 μm. The supersaturation in the CCN counter with varying temperature difference was determined by using size-selected sodium chloride particles based on K?hler equation. The developed CCN counter was applied to investigate CCN activity of atmospheric ultrafine particles at 0.5% supersaturation. Data showed that CCN activity increased with increasing particle size and that the higher CCN activation for ultrafine particles occurred in the afternoon, suggesting the significant existence of hygroscopic or soluble species in photochemically-produced ultrafine particles.

关键词： aerosol     cloud condensation nuclei (CCN) counter     ultrafine particle    

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Key features of new particle formation events at background sites in China and their influence on cloudcondensation nuclei

Xiaojing SHEN,Junying SUN,Xiaoye ZHANG,Yangmei ZHANG,Lu ZHANG,Ruxia FAN

《环境科学与工程前沿（英文）》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0833-2

摘要： New particle formation (NPF) event at multi rural sites in China Identifying the characteristics of NPF event Comparing NPF event between clean and polluted conditions Quantifying contribution to the cloud condensation nuclei Implication of climate and air quality Long-term continuous measurements of particle number size distributions with mobility diameter sizes ranging from 3 to 800 nm were performed to study new particle formation (NPF) events at Shangdianzi (SDZ), Mt. Tai (TS), and Lin’an (LAN) stations representing the background atmospheric conditions in the North China Plain (NCP), Central East China (CEC), and Yangtze River Delta (YRD) regions, respectively. The mean formation rate of 3-nm particles was 6.3, 3.7, and 5.8 cm ·s , and the mean particle growth rate was 3.6, 6.0, and 6.2 nm·h at SDZ, TS, and LAN, respectively. The NPF event characteristics at the three sites indicate that there may be a stronger source of low volatile vapors and higher condensational sink of pre-existing particles in the YRD region. The formation rate of NPF events at these sites, as well as the condensation sink, is approximately 10 times higher than some results reported at rural/urban sites in western countries. However, the growth rates appear to be 1–2 times higher. Approximately 12%–17% of all NPF events with nucleated particles grow to a climate-relevant size (>50 nm). These kinds of NPF events were normally observed with higher growth rate than the other NPF cases. Generally, the cloud condensation nuclei (CCN) number concentration can be enhanced by approximately a factor of 2–6 on these event days. The mean value of the enhancement factor is lowest at LAN (2–3) and highest at SDZ (~4). NPF events have also been found to have greater impact on CCN production in China at the regional scale than in the other background sites worldwide.

关键词： New particle formation     Regional background     Cloud condensation nuclei     Growth rate     Formation rate    

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Global sources, emissions, transport and deposition of dust and sand and their effects on the climate and environment: a review

Feng Wang, Xueqiu Zhao, Cynthia Gerlein-Safdi, Yue Mu, Dongfang Wang, Qi Lu

《环境科学与工程前沿（英文）》 2017年 第11卷 第1期 doi: 10.1007/s11783-017-0904-z

摘要： Dust and Sand Storms (DSS) originating in deserts in arid and semi-arid regions are events raising global public concern. An important component of atmospheric aerosols, dust aerosols play a key role in climatic and environmental changes at the regional and the global scale. Deserts and semi-deserts are the main source of dust and sand, but regions that undergo vegetation deterioration and desertification due to climate change and human activities also contribute significantly to DSS. Dust aerosols are mainly composed of dust particles with an average diameter of 2 m, which can be transported over thousands of kilometers. Dust aerosols influence the radiation budget of the earth-atmosphere system by scattering solar short-wave radiation and absorbing surface long-wave radiation. They can also change albedo and rainfall patterns because they can act as cloud condensation nuclei (CCN) or ice nuclei (IN). Dust deposition is an important source of both marine nutrients and contaminants. Dust aerosols that enter marine ecosystems after long-distance transport influence phytoplankton biomass in the oceans, and thus global climate by altering the amount of CO absorbed by phytoplankton. In addition, the carbonates carried by dust aerosols are an important source of carbon for the alkaline carbon pool, which can buffer atmospheric acidity and increase the alkalinity of seawater. DSS have both positive and negative impacts on human society: they can exert adverse impacts on human’s living environment, but can also contribute to the mitigation of global warming and the reduction of atmospheric acidity.

关键词： Dust and sand storm     Climate effects     Radiative forcing     Cloud condensation nuclei     Precipitation     Iron fertilizer    

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Effect of counter current gas phase on liquid film

Shujuan LUO, Huaizhi LI, Weiyang FEI, Yundong WANG

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 135-137 doi: 10.1007/s11705-009-0129-1

摘要： Liquid film flow is very important in many industrial applications. However, there are few reports about its characteristics on structured packings. Therefore, in this paper, liquid film phenomena were investigated experimentally to exploit new approaches for intensifying the performance of the structured packings. All experiments were performed at room temperature. Water and air were the working fluids. The effect of counter current gas phase on the liquid film was taken into consideration. A high speed camera, a non-intrusive measurement technique, was used. It is shown that both liquid and gas phases have strong effects on film characteristics. In the present work, liquid film width increased by 57% because of increasing liquid flow rate, while it decreased by 25% resulting from the counter current gas phase.

关键词： counter current     liquid film     two phases     structured packings    

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Thermodynamic performance experiment and cooling number calculation of a counter-flow spray humidifier

WANG Yuzhang, LI Yixing, WENG Shilie, WANG Yonghong

《能源前沿（英文）》 2008年 第2卷 第1期   页码 43-47 doi: 10.1007/s11708-008-0005-6

摘要： An experimental investigation of the thermodynamic performance of a counter-flow spray humidifier was conducted on the basis of theoretical analysis of the heat and mass transfer mechanism inside the humidifier. Critical parameters such as the temperature and relative humidity of air and the temperature of water at the inlet and outlet were measured. The influence of every measured parameter on the thermal performance of the humidifier was obtained under different experimental conditions. The cooling number, whose variation was also obtained, was calculated according to the measured data. The experimental results show that both the temperature and the temperature increment of outlet humid air and the temperature of outlet water increase with an increase of the water-gas ratio, whereas the cooling number decreases. Under all experimental conditions, the outlet humid air reaches or is close to the saturation level. The lower cooling number is favorable for the system, but it has an optimal value for a certain humidifier.

关键词： temperature increment     counter-flow     experimental investigation     temperature     water-gas    

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Finite element modeling of counter-roller spinning for large-sized aluminum alloy cylindrical parts

Dawei ZHANG, Fan LI, Shuaipeng LI, Shengdun ZHAO

《机械工程前沿（英文）》 2019年 第14卷 第3期   页码 351-357 doi: 10.1007/s11465-019-0528-z

摘要： Counter-roller spinning (CRS), where the mandrel is replaced by rollers, is an effective means of manufacturing large-sized, thin-walled, cylindrical parts with more than 2500 mm diameter. CRS is very complex because of multi-axis rotation, multi-local loading along the circumference, and radial-axial compound deformation. Analytical or experimental methods cannot fully understand CRS. Meanwhile, numerical simulation is an adequate approach to investigate CRS with comprehensive understanding and a low cost. Thus, a finite element (FE) model of CRS was developed with the FORGE code via meshing technology, material modeling, determining the friction condition, and so on. The local fine mesh moving with the roller is one of highlights of the model. The developed 3D-FE model was validated through a CRS experiment by using a tubular blank with a 720 mm outer diameter. The developed 3D-FE model of CRS can provide a basis for parameter optimization, process control, die design, and so on. The data on force and energy predicted by the 3D-FE model can offer reasonable suggestions for determining the main mechanical parameters of CRS machines and selecting the motors. With the predicted data, an all-electric servo-drive system/machine with distributed power was designed in this work for CRS with four pairs of rollers to manufacture a large-sized, thin-walled, cylindrical part with 6000 mm diameter.

关键词： large-sized cylindrical part     counter-roller spinning     aluminum alloy     finite element method     distributed power    

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The Development Situation, Future and Counter Measures of Remanufacturing Industry in China

Wen-qiang Liu,Jun-yuan Mo,Cheng-kui Gu

《工程管理前沿（英文）》 2016年 第3卷 第2期   页码 123-131 doi: 10.15302/J-FEM-2016021

摘要： Currently, resource supply and demand contradiction, and over-loaded environment capacity have become a bottleneck for sustainable economic development in China. Electro-mechanical products are approaching a peak of obsolescence, and massive abandoned electro-mechanical products are causing severe environmental pollution, huge waste of resources and potential safety hazard. Remanufacturing is repairing or modifying worn mechanical products using high-tech method, which buffers the contradiction between wasting and shortage of resources, and brings industry towards a comprehensive utilization of resource and environmental protection. As a new strategic industry, remanufacturing, which is highly coherent with the development strategy of the circular economy, is still in its infancy in China. This paper analyzes the developmental trends and problems of the remanufacturing industry in China, and proposes promoting measures based on the engineering practices of remanufacturing.

关键词： remanufacturing     industry     measures     development    

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Application of high-speed counter-current chromatography coupled with high performance liquid chromatography

Shengguo DENG, Zeyuan DENG, Yawei FAN, Jing LI, Rong LIU, Dongmei XIONG,

《化学科学与工程前沿（英文）》 2009年 第3卷 第4期   页码 375-382 doi: 10.1007/s11705-009-0247-9

摘要： Quercetin-3--sambubioside Quercetin-3--β-D-xylopyranosyl (1→2)-β-D-glucopyranoside was separated and purified by semi-preparative high-speed counter-current chromatography (HSCCC) with a two-phase-solvent system composed of ethyl acetate-n-butanol–water (4∶1∶5, v/v) from the leaves of (Lotus). A total of 5.0mg of the targeted compound with a purity of 98.6% as determined by high performance liquid chromatography (HPLC) was obtained from 100m g of the crude extract cleaned up by AB-8 macroporous resin in a one-step separation. Quercetin-3--sambubioside was a novel flavonoid glycoside from the leaves of , and its chemical structure was identified by means of ESI-MS, 1D NMR and 2D NMR.

关键词： two-phase-solvent     flavonoid glycoside     high-speed counter-current     macroporous     counter-current chromatography    

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IN2CLOUD: A novel concept for collaborative management of big railway data

Jing LIN, Uday KUMAR

《工程管理前沿（英文）》 2017年 第4卷 第4期   页码 428-436 doi: 10.15302/J-FEM-2017048

摘要： In the EU Horizon 2020 Shift2Rail Multi-Annual Action Plan, the challenge of railway maintenance is generating knowledge from data and/or information. Therefore, we promote a novel concept called “IN2CLOUD,” which comprises three sub-concepts, to address this challenge: 1) A hybrid cloud, 2) an intelligent cloud with hybrid cloud learning, and 3) collaborative management using asset-related data acquired from the intelligent hybrid cloud. The concept is developed under the assumption that organizations want/need to learn from each other (including domain knowledge and experience) but do not want to share their raw data or information. IN2CLOUD will help the movement of railway industry systems from “local” to “global” optimization in a collaborative way. The development of cutting-edge intelligent hybrid cloud-based solutions, including information technology (IT) solutions and related methodologies, will enhance business security, economic sustainability, and decision support in the field of intelligent asset management of railway assets.

关键词： railway     intelligent asset management     collaborative learning     big data     hybrid cloud     Bayesian    

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Toward autonomous mining: design and development of an unmanned electric shovel via point cloud-based

《机械工程前沿（英文）》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0686-2

摘要： With the proposal of intelligent mines, unmanned mining has become a research hotspot in recent years. In the field of autonomous excavation, environmental perception and excavation trajectory planning are two key issues because they have considerable influences on operation performance. In this study, an unmanned electric shovel (UES) is developed, and key robotization processes consisting of environment modeling and optimal excavation trajectory planning are presented. Initially, the point cloud of the material surface is collected and reconstructed by polynomial response surface (PRS) method. Then, by establishing the dynamical model of the UES, a point to point (PTP) excavation trajectory planning method is developed to improve both the mining efficiency and fill factor and to reduce the energy consumption. Based on optimal trajectory command, the UES performs autonomous excavation. The experimental results show that the proposed surface reconstruction method can accurately represent the material surface. On the basis of reconstructed surface, the PTP trajectory planning method rapidly obtains a reasonable mining trajectory with high fill factor and mining efficiency. Compared with the common excavation trajectory planning approaches, the proposed method tends to be more capable in terms of mining time and energy consumption, ensuring high-performance excavation of the UES in practical mining environment.

关键词： autonomous excavation     unmanned electric shovel     point cloud     excavation trajectory planning    

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Toward resilient cloud warehousing via a blockchain-enabled auction approach

《工程管理前沿（英文）》   页码 20-38 doi: 10.1007/s42524-022-0224-2

摘要： Cloud warehousing service (CWS) has emerged as a promising third-party logistics service paradigm driven by the widespread use of e-commerce. The current CWS billing method is typically based on a fixed rate in a coarse-grained manner. This method cannot reflect the true service value under the fluctuating e-commerce logistics demand and is not conducive to CWS resilience management. Accordingly, a floating mechanism can be considered to introduce more flexible billing. A CWS provider lacks sufficient credibility to implement floating mechanisms because it has vested interests in terms of fictitious demand. To address this concern, this report proposes a blockchain-enabled floating billing management system as an overall solution for CWS providers to enhance the security, credibility, and transparency of CWS. A one-sided Vickrey–Clarke–Groves (O-VCG) auction mechanism model is designed as the underlying floating billing mechanism to reflect the real-time market value of fine-grained CWS resources. A blockchain-based floating billing prototype system is built as an experimental environment. Our results show that the O-VCG mechanism can effectively reflect the real-time market value of CWSs and increase the revenue of CWS providers. When the supply of CWS providers remains unchanged, allocation efficiency increases when demand increases. By analyzing the performance of the O-VCG auction and comparing it with that of the fixed-rate billing model, the proposed mechanism has more advantages. Moreover, our work provides novel managerial insights for CWS market stakeholders in terms of practical applications.

关键词： resilient cloud warehousing     blockchain technology     floating billing management system     auction mechanism     third-party logistics    

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用于图像融合基于混合全加器和计数器的高效华莱士树型乘法器 Research Articles

Ayoub SADEGHI, Nabiollah SHIRI, Mahmood RAFIEE, Mahsa TAHGHIGH

《信息与电子工程前沿（英文）》 2022年 第23卷 第6期   页码 950-965 doi: 10.1631/FITEE.2100432

摘要：

提出一种新的基于计数器的华莱士树（CBW）8×8乘法器。乘法器的计数器使用基于传输门技术的新型混合全加器单元。所提全加器、基于传输门的与门和混合半加器生成M:3（4≤M≤7）数字计数器，能够节省至少50%的面积。通过90 nm技术仿真证明所提全加器和数字计数器在不同条件下均优于当前最先进设计。通过使用所提单元，CBW乘法器表现出高驱动、低功耗和高速性能。CBW乘法器在焊盘中的芯片面积为0.0147 mm2。后布局提取证明了实验的准确性。同时提出一种图像融合机制，其中MATLAB和HSPICE之间的直接接口用于在图像处理应用中评估所提CBW乘法器。峰值信噪比和结构相似性指数度量被用作图像质量参数，结果证实所提CBW乘法器可以替代文献中的设计。

关键词： 全加器；传输门；计数器；乘法器；三维布局；图像融合    

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云雷达反演层状云微物理参数及其与飞机观测数据的对比

刘黎平,宗蓉,齐彦斌,刘健

《中国工程科学》 2012年 第14卷 第9期   页码 64-71

摘要：

首先根据滴谱假设分析了层状云降水回波强度、径向速度和速度谱宽与降水微物理参数的关系，检验了云雷达探测数据的可用性；然后在忽略空气上升速度和湍流对雷达观测的速度谱宽影响前提下，利用测云雷达观测的回波强度、粒子下落速度和速度谱宽数据进行了液态水含量和滴谱参数的反演试验，并与飞机观测的滴谱进行了对比分析。结果表明，8 mm雷达观测得到的3个量与雨滴谱分析得到的关系比较接近；层状云粒子尺度、数密度和含水量从云顶到云的回波强中心有明显的变化，粒子尺度的增加是回波强度增加的重要原因。毫米波雷达反演得到的降水微物理参数和飞机观测数据具有可比性。

关键词： 云降水微物理参数     毫米波云雷达和飞机观测     降水粒子下落速度和谱宽    

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Review of the LNG intermediate fluid vaporizer and its heat transfer characteristics

《能源前沿（英文）》 2022年 第16卷 第3期   页码 429-444 doi: 10.1007/s11708-021-0747-y

摘要： The intermediate fluid vaporizer (IFV), different from other liquefied natural gas (LNG) vaporizers, has many advantages and has shown a great potential for future applications. In this present paper, studies of IFV and its heat transfer characteristics in the LNG vaporization unit E2 are systematically reviewed. The research methods involved include theoretical analysis, experimental investigation, numerical simulation, and process simulation. First, relevant studies on the overall calculation and system design of IFV are summarized, including the structural innovation design, the thermal calculation model, and the selection of different intermediate fluids. Moreover, studies on the fluid flow and heat transfer behaviors of the supercritical LNG inside the tubes and the condensation heat transfer of the intermediate fluid outside the tubes are summarized. In the thermal calculations of the IFV, the selections of the existing heat transfer correlations about the intermediate fluids are inconsistent in different studies, and there lacks the accuracy evaluation of those correlations or comparison with experimental data. Furthermore, corresponding experiments or numerical simulations on the cryogenic condensation heat transfer outside the tubes in the IFV need to be further improved, compared to those in the refrigeration and air-conditioning temperature range. Therefore, suggestions for further studies of IFV are provided as well.

关键词： intermediate fluid vaporizer     design of structure and intermediate fluid     condensation heat transfer    

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基于云模型的信任评估研究

路峰,吴慧中

《中国工程科学》 2008年 第10卷 第10期   页码 84-90

摘要：

讨论了信任关系的随机性和模糊性共存以及相互融合问题。分析云模型描述不确定性概念的方法和实现定性语意与定量数值相互转换的算法，提出了基于云理论的信任评估模型—信任云。该模型提出云特征参数表达的信任传递和合并算法，在精确描述信任期望值的同时，通过熵和超熵刻画了信任的不确定性。相对于传统的信任评估策略，该模型获取的信任值包含更多的语意信息，更适合作为信任决策的依据。

关键词： 信任评估     信任模型     云模型     云发生器    

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标题 作者 时间 类型 操作

Development of a cloud condensation nuclei (CCN) counter using a laser and charge-coupled device (CCD

Mikyung PARK, Jinkwan OH, Kihong PARK

期刊论文

Key features of new particle formation events at background sites in China and their influence on cloudcondensation nuclei

Xiaojing SHEN,Junying SUN,Xiaoye ZHANG,Yangmei ZHANG,Lu ZHANG,Ruxia FAN

期刊论文

Global sources, emissions, transport and deposition of dust and sand and their effects on the climate and environment: a review

Feng Wang, Xueqiu Zhao, Cynthia Gerlein-Safdi, Yue Mu, Dongfang Wang, Qi Lu

期刊论文

Effect of counter current gas phase on liquid film

Shujuan LUO, Huaizhi LI, Weiyang FEI, Yundong WANG

期刊论文

Thermodynamic performance experiment and cooling number calculation of a counter-flow spray humidifier

WANG Yuzhang, LI Yixing, WENG Shilie, WANG Yonghong

期刊论文

Finite element modeling of counter-roller spinning for large-sized aluminum alloy cylindrical parts

Dawei ZHANG, Fan LI, Shuaipeng LI, Shengdun ZHAO

期刊论文

The Development Situation, Future and Counter Measures of Remanufacturing Industry in China

Wen-qiang Liu,Jun-yuan Mo,Cheng-kui Gu

期刊论文

Application of high-speed counter-current chromatography coupled with high performance liquid chromatography

Shengguo DENG, Zeyuan DENG, Yawei FAN, Jing LI, Rong LIU, Dongmei XIONG,

期刊论文

IN2CLOUD: A novel concept for collaborative management of big railway data

Jing LIN, Uday KUMAR

期刊论文

Toward autonomous mining: design and development of an unmanned electric shovel via point cloud-based

期刊论文

Toward resilient cloud warehousing via a blockchain-enabled auction approach

期刊论文

用于图像融合基于混合全加器和计数器的高效华莱士树型乘法器

Ayoub SADEGHI, Nabiollah SHIRI, Mahmood RAFIEE, Mahsa TAHGHIGH

期刊论文

云雷达反演层状云微物理参数及其与飞机观测数据的对比

刘黎平,宗蓉,齐彦斌,刘健

期刊论文

Review of the LNG intermediate fluid vaporizer and its heat transfer characteristics

期刊论文

基于云模型的信任评估研究

路峰,吴慧中

期刊论文