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Fundamental Theories and Key Technologies for Smart andOptimal Manufacturing in the Process Industry

Engineering 2017年第2期3卷 154-160页

作者： Feng qian Weimin zhong Wenli Du Key Laboratory of Aflvanced Control and Optimization for Chemical Processes Ministry of Education East China University of Science and TechnologyShanghai 200237 China

Given the significant requirements for transforming and promoting the process industry, we present themajor limitations of current petrochemical enterprises, including limitations in decision-making, produc-tion operation, efficiency and security, information integration, and so forth. To promote a vision of theprocess industry with efficient, green, and smart production, modern information technology should beutilized throughout the entire optimization process for production, management, and marketing. To focuson smart equipment in manufacturing processes, as well as on the adaptive intelligent optimization of themanufacturing process, operating mode, and supply chain management, we put forward several key scien-tific problems in engineering in a demand-driven and application-oriented manner, namely：intelligentsensing and integration of all process information, including production and management information; collaborative decision-making in the supply chain, industry chain, and value chain, driven by knowledge; cooperative control and optimization of plant-wide production processes via human-cyber-physical in-teraction; and Q life-cycle assessments for safety and environmental footprint monitoring, in addition totracing analysis and risk control. In order to solve these limitations and core scientific problems, we furtherpresent fundamental theories and key technologies for smart and optimal manufacturing in the processindustry. Although this paper discusses the process industry in China, the conclusions in this paper can beextended to the larocess industry around the world.

关键词： Process industry Smart and optimal manufacturing Green manufacturing High-end manufacturing Optimality assessment

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Supervised Contrastive Learning with Term Weighting for Improving Chinese Text Classification

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Tsinghua Science and Technology 2023年第1期28卷 59-68页

作者： Jiabao Guo Bo Zhao Hui Liu Yifan Liu qian zhong School of Cyber Science and Engineering Wuhan UniversityWuhan 430000China

With the rapid growth of information retrieval technology,Chinese text classification,which is the basis of information content security,has become a widely discussed *** view of the huge difference compared with English,Chinese text task is more complex in semantic information ***,most existing Chinese text classification approaches typically regard feature representation and feature selection as the key points,but fail to take into account the learning strategy that adapts to the ***,these approaches compress the Chinese word into a representation vector,without considering the distribution of the term among the categories of *** order to improve the effect of Chinese text classification,a unified method,called Supervised Contrastive Learning with Term Weighting(SCL-TW),is proposed in this *** contrastive learning makes full use of a large amount of unlabeled data to improve model *** SCL-TW,we calculate the score of term weighting to optimize the process of data augmentation of Chinese ***,the transformed features are fed into a temporal convolution network to conduct feature *** verifications are conducted on two Chinese benchmark *** results demonstrate that SCL-TW outperforms other advanced Chinese text classification approaches by an amazing margin.

关键词： Chinese text classification Supervised Contrastive Learning(SCL) Term Weighting(TW) Temporal Convolution Network(TCN)

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Determination of groundwater flow regimes based on the spatial non-local distribution of hydraulic gradient:Model and validation

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Journal of Hydrodynamics 2022年第2期34卷 299-307页

作者： Xiu-xuan Wang Jia-zhong qian Lei Ma qian-kun Luo Guan-qun Zhou School of Resources and Environmental Engineering Hefei University of TechnologyHefei230009China

The groundwater flow in natural aquifers can change from the Darcy flow to the non-Darcian flow due to a variety of causes,such as the increase of the Reynolds number in the highly permeable media or the decrease of the hydraulic gradient below a threshold in the low-permeability media,while the representative flow regime cannot be reliably determined using the traditional *** address this challenge,this paper proposes a new term called the equivalent hydraulic gradient(EHG)by generalizing the differential form of the Darcy’s law using a spatial integral of the upstream hydraulic *** nonlocal spatial variation of the hydraulic head difference between upstream and downstream zones is assumed to be the potential cause of the transition of the groundwater flow *** assumption is analogous to the common assumption used for quantifying the anomalous pollutant transport in the geological *** of this idea show that the EHG concept could distinguish three main flow regimes,namely the Super-Darcy flow,the Darcy flow,and the Sub-Darcy flow,although the Super-Darcy flow regime is rarely observed in the laboratory column flow *** of this study therefore shed lights on the interpretation of the fundamental dynamics of the groundwater moving in various heterogeneous aquifers,and may lead to the rebuilding of the hydrodynamics of the surface water,the groundwater,and the soil.

关键词： Hydraulic head distribution spatially non-local effect flow regime Forchheimer number Reynolds number

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EXPERIMENTAL STUDY OF THE NON-DARCY FLOW AND SOLUTE TRANSPORT IN A CHANNELED SINGLE FRACTURE

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Journal of Hydrodynamics 2011年第6期23卷 745-751页

作者： CHEN Zhou qian Jia-zhong QIN Hua School of Resources and Environmental Engineering Hefei University of Technology Hefei 230009 China

The characterization of fracture rocks is always a key issue in understanding the flow and solute transport in fractured media. This article studies the solute transport in a Channeled Single Fracture （CSF）, a single fracture with contact in certain areas. The flow in a CSF often has preferential pathways and the transport in a CSF often has Break Through Curves （BTCs） with long tails. The Surface Contact Ratio （SCR）, the ratio of the contact area to the total fracture area, is an important indicator for the fracture surface roughness. To study the flow and solute transport in a CSF, a controlled physical model is constructed and a series of flow and tracer test experiments are carried out. Under our experimental conditions, the flow in a CSF is found to follow the Forchheimer equation , where and are the hydraulic gradient and the average pore velocity, respectively and and are two parameters related to the viscous and inertial flow components, respectively. Furthermore, it is found that b decreases with the decrease of SCR. For the solute transport, it is found that the BTCs often deviate from the traditional Fickian behavior, by the early-arrival and the long tailing. More interestingly, the observed BTCs often have a double-peak or a multi-peak, that would be difficult to explain using the existing transport theory such as the Advection-Dispersion Equation （ADE）. In addition, the longitudinal dispersion coefficient is found to be scale-dependent in a CSF and the relationship is of exponential type.

关键词： channeled single fracture surface contact ratio non-Darcian non-Fickian

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EXPERIMENTAL STUDY OF AIRFLOW INDUCED BY PUMPING TESTS IN UNCONFINED AQUIFER WITH LOW-PERMEABILITY CAP

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Journal of Hydrodynamics 2012年第4期24卷 605-608页

作者： HUANG Hui qian Jia-zhong KUANG Xing-xing CHEN Zhou LI Ru-zhong School of Resources and Environmental Engineering Hefei University of Technology Hefei 230009 China Department of Earth Sciences The University of Hong Kong Hong Kong China

The airflow in unsaturated soils is an issue of great importance in various fields such as in agricultural, nuclear, environmental engineering. However, up to now, little attention was paid to the generation of the airflow induced by a pumping test in an unconfined aquifer with a low-permeability cap and its influence on the pumping test. In this paper, pumping tests were carried out experimentally in the aquifer with a low-permeability cap in order to study the influence of the airflow induced by the pumping on the drawdown of the tests. It is shown that：（1） there is an airflow with negative pressure generated by the pumping tests, （2） the Negative air Pressure （NP） is increased with the pumping rate but decreased with the radial distance, and （3） the NP also changes with the initial water table. The results provide a good basis for further theoretical study of the airflow induced by pumping.

关键词： low-permeability cap pumping tests airflow unconfined aquifer drawdown

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Hyperbilirubinemia after extracorporeal circulation surgery:A recent and prospective study

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World Journal of Gastroenterology 2006年第41期12卷 6722-6726页

作者： Yong An Ying-Bin Xiao qian-Jin zhong Department of Cardiovascular Surgery Xin-Qiao Hospital Third Military Medical University Chongqing 400037 China

AIM： To clarify the incidence and nature of postoperative hyperbilirubinemia in patients after modern extracorporeal circulation, to analyze possible perioperative risk factors, and to elucidate the clinical significance of postoperative hyperbilirubinemia associated mortality and morbidity. METHODS： Between March 2005 and May 2006, three hundred and eighty six consecutive patients undergoing extracorporeal circulation surgery due to a variety of cardiac lesions were investigated prospectively. The incidence of postoperative hyperbilirubinemia was defined as a serum total bilirubin concentration of more than 51 μmol/L. Several perioperative parameters were compared by logistic regression between hyperbilirubinemia and non-hyperbilirubinemia patients to determine possible risk factors contributing to postoperative hyperbilirubinemia and mortality. RESULTS： Overall incidence of postoperative hyperbilirubinemia was 25.3% （98/386）. In patients with postoperative hyperbilirubinemia, 56.2% reached peak total bilirubin concentration on the first postoperative day, 33.5% on the second day, and 10.3% on the seventh day. Eighty percent of the increase of total bilirubin resulted from an increase of both conjugated and unconjugated bilirubin. Development of postoperative hyperbilirubinemia was associated with a higher mortality （P 〈 0.01）, longer duration of mechanical ventilation （P 〈 0.05） and longer ICU stay time （P 〈 0.05）. Preoperative total bilirubin concentration, preoperative right atrium pressure, numbers of valves replaced and of blood transfusion requirement were identified as important predictors for postoperative hyperbUirubinemia. CONCLUSION： Early postoperative hyperbilirubinemia after modern extracorporeal circulation is mainly caused by an increase in both conjugated and unconjugated bilirubin, and is associated with a high mortality. Important contributing factors are the preoperative total bilirubin concentration, preoperative severity of right atrial pressu

关键词： Extracorporeal circulation Open-heart surgery Hyperbilirubinemia Liver function

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CURVED OPEN CHANNEL FLOW ON VEGETATION ROUGHENED INNER BANK

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Journal of Hydrodynamics 2012年第1期24卷 124-129页

作者： HUAI Wen-xin LI Cheng-guang ZENG Yu-hong qian zhong-dong YANG zhong-hua State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China

A RNG numerical model together with a laboratory measurement with Micro ADV are adopted to investigate the flow through a 180o curved open channel（a 4 m straight inflow section,a 180o curved section,and a 4m straight outflow section）partially covered with rigid vegetations on its inner *** the combined action of the vegetation and the bend flow,the flow structure is *** stream-wise velocities in the vegetation region are much smaller than those in the non-vegetation region due to the retardation caused by the *** the same reason,no clear circulation is found in the vegetated region,while in the non-vegetation region,a slight counter-rotating circulation is found near the outer bank at both 90o and downstream curved cross-sections.A comparison between the numerical prediction and the laboratory measurement shows that the RNG model can well predict the flow structure of the bend flow with ***,the shear stress is analyzed based on the numerical *** much smaller value in the inner vegetated region indicates that the vegetation can effectively protect the river bank from scouring and erosion,in other words,the sediment is more likely to be deposited in the vegetation region.

关键词： RNG numerical model non-submerged rigid vegetation bend flow stream-wise velocities shear stress

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Budget Allocation for Maximizing Viral Advertising in Social Networks

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Journal of Computer Science & Technology 2016年第4期31卷 759-775页

作者： Bo—LeiZhang Zhu-zhong qian Wen-zhong Li Bin Tang Sang-Lu Lu Xiaoming Fu State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210023 China Institute of Computer Science University of G5ttingen G5ttingen 37077 Germany

Viral advertising in social networks has arisen as one of the most promising ways to increase brand awareness and product sales. By distributing a limited budget, we can incentivize a set of users as initial adopters so that the advertising can start from the initial adopters and spread via sociM links to become viral. Despite extensive researches in how to target the most influential users, a key issue is often neglected： how to incentivize the initial adopters. In the problem of influence maximization, the assumption is that each user has a fixed cost for being initial adopters, while in practice, user decisions for accepting the budget to be initial adopters are often probabilistic rather than deterministic. In this paper, we study optimal budget allocation in social networks to maximize the spread of viral advertising. In particular, a concave probability model is introduced to characterize each user＇s utility for being an initial adopter. Under this model, we show that it is NP-hard to find an optimal budget allocation for maximizing the spread of viral advertising. We then present a novel discrete greedy algorithm with near optimal performance, and further propose scaling-up techniques to improve the time-efficiency of our algorithm. Extensive experiments on real-world social graphs are implemented to validate the effectiveness of our algorithm in practice. The results show that our algorithm can outperform other intuitive heuristics significantly in almost all cases.

关键词： social network influence maximization information diffusion submodular optimization

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Asynchronism of the spreading dynamics underlying the bursty pattern

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Chinese Physics B 2020年第5期29卷 586-592页

作者： Tong Wang Ming-Yang Zhou zhong-qian Fu Department of Electronic Science and Technology University of Science and Technology of ChinaHefei 230027China Guangdong Province Key Laboratory of Popular High Performance Computers College of Computer Science and Software EngineeringShenzhen UniversityShenzhen 518060China Department of Physics University of FribourgChemin du Mus´ee 3FribourgCH-1700Switzerland

The potential mechanisms of the spreading phenomena uncover the organizations and functions of various ***,due to the lack of valid data,most of early works are limited to the simulated process on model *** this paper,we track and analyze the propagation paths of real spreading events on two social networks:Twitter and *** empirical analysis reveals that the spreading probability and the spreading velocity present the explosive growth within a short period,where the spreading probability measures the transferring likelihood between two neighboring nodes,and the spreading velocity is the growth rate of the information in the whole ***,we observe the asynchronism between the spreading probability and the spreading *** explain the interesting and abnormal issue,we introduce the time-varying spreading probability into the susceptible-infected(SI)and linear threshold(LT)*** the analytic and experimental results reproduce the spreading phenomenon in real networks,which deepens our understandings of spreading problems.

关键词： social network information diffusion spreading probability asynchronism

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Thermodynamic Properties of Linear Protein Solutions:an Application to Type Ⅰ Antifreeze Protein Solutions

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Chemical Research in Chinese Universities 2012年第6期28卷 1070-1073页

作者： LI Li-fen LIANG Xi-xia LI qian-zhong Department of Physics lnner Mongolia University Hohhot 010021 P. R. China Department of Basic Curriculum North China Institute of Science and Technology Beijing 101601 P. R. China

A statistical thermodynamic theory of linear protein solutions was proposed with the aid of a lattice model and applied to type Ⅰ antifreeze protein（AFPI） *** numerical results for several AFPI solutions show that the Gibbs function of the solution has a minimum at a certain protein concentration,but the protein chemical potential increases with increasing the *** influences of temperature and protein chain length on the AFPI chemical potential were also *** evaluation for the colligative depression of the freezing point confirms that the antifreeze action should be recognized as *** theoretical deduction for the concentration dependence of the thermal hysteresis activity coincides qualitatively with the previous experimental and theoretical results.

关键词： Antifreeze protein solution Gibbs function Chemical potential Thermal hysteresis

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