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A rate-based method for dynamic analysis and optimal design of reactive extraction: n-Hexyl acetate esterification as an example

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Chinese Journal of Chemical Engineering 2020年第1期28卷 76-83页

作者： Xutao Hu Hao Qin Biao Hu Hongye Cheng Lifang Chen Zhiwen Qi Max Planck Partner Group at the State Key Laboratory of Chemical Engineering School of Chemical Engineering East China University of Science and Technology

The dynamic analysis and optimal design of reactive extraction are challenging due to high nonlinearity of model equations and tough decision of judging criteria. In this work, a dynamic rate-based method is developed on g PROMS platform to get easy access to the solutions of reactive extraction with phase splitting. Based on rigorous criteria, dynamic analysis from initial state to final equilibrium(e.g., evolution of phase composition, mass transfer rate and reaction rate) and optimal design of operating conditions(e.g., extractant dosage and feed molar ratio) are achieved. To illustrate the method, the esterification of n-hexyl acetate is taken as an example. The approach proves to be reliable in the analysis and optimization of the exemplified system, which provides instructive reference for further process design and simulation of reactive extraction.

关键词： Reactive extraction Dynamic rate-based method Optimal design Process simulation n-Hexyl acetate esterification

Innovative piled raft foundations design using artificial neural network

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Frontiers of Structural and Civil Engineering 2020年第1期14卷 138-146页

作者： Meisam RABIEI Asskar Janalizadeh CHOOBBASTI Department of Civil Engineering Babol Noshirvani University of TechnologyBabol ***Iran

Studying the piled raft behavior has been the subject of many types of research in the field of geotechnical engineering.Several studies have been conducted to understand the behavior of these types of foundations,which are often used for uniform loading on the raft and piles with the same length,while generally the transition load from the upper structure to the foundation is non-uniform and the choice of uniform length for piles in the above model will not be optimally economic and practical.The most common method in identifying the behavior of piled rafts is the use of theoretical relationships and software analyses.More precise identification of this type of foundation behavior can be very difficult due to several influential parameters and interaction of set behavior,and it will be done by doing time-consuming computer analyses or costly full-scale physical modeling.In the meantime,the technique of artificial neural networks can be used to achieve this goal with minimum time consumption,in which data from physical and numerical modeling can be used for network learning.One of the advantages of this method is the speed and simplicity of using it.In this paper,a model is presented based on multi-layer perceptron artificial neural network.In this model pile diameter,pile length,and pile spacing is considered as an input parameter that can be used to estimate maximum settlement,maximum differential settlement,and maximum raft moment.By this model,we can create an extensive domain of results for optimum system selection in the desired piled raft foundation.Results of neural network indicate its proper ability in identifying the piled raft behavior.The presented procedure provides an interesting solution and economically enhancing the design of the piled raft foundation system.This innovative design method reduces the time spent on software analyses.

关键词： innovative design piled raft foundation neural network optimization

Optimization and characterization of deoxypodophyllotoxin loaded mPEG-PDLLA micelles by central composite design with response surface methodology

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Chinese Journal of Natural Medicines 2018年第6期16卷 471-480页

作者： YU Ying-Lan LI Ya-Nan ZHANG Yong SUN Ru-Ning TU Jia-Sheng SHEN Yan Department of Pharmaceutics School of PharmacyChina Pharmaceutical UniversityNanjing 210009China Children's Hospital of Nanjing Medical University Nanjing 210008China Department of Professional Institute China Pharmaceutical UniversityNanjing 210009China

The therapeutic application of deoxypodophyllotoxin(DPT) is limited due to its poor water solubility and stability. In the present study, the micelles assembled by the amphiphilic block copolymers(m PEG-PDLLA) were constructed to improve the solubility and safety of DPT for their in vitro and in vivo application. The central composite design was utilized to develop the optimal formulation composed of 1221.41 mg m PEG-PDLLA, the weight ratio of 1 : 4(m PEG-PDLLA : DPT), 30 m L hydration volume and the hydration temperature at 40 oC. The results showed that the micelles exhibited uniformly spherical shape with the diameter of 20 nm. The drug-loading and entrapment efficiency of deoxypodophyllotoxin-polymeric micelles(DPT-PM) were about(20 ± 2.84)% and(98 ± 0.79)%, respectively, indicating that the mathematical models predicted well for the results. Compared to the free DPT, the cytotoxicity showed that blank micelles possessed great safety for Hela cells. In addition, the DPT loaded micelle formulation achieved stronger cytotoxicity at the concentration of 1 × 10^(-7) mol·L^(-1), which showed significant difference from free DPT(P < 0.05). In conclusion, the micelles were highly promising nano-carriers for the anti-tumor therapy with DPT.

关键词： Deoxypodophyllotoxin Central composite design Micelles Cytotoxicity

Analysis of coal pillar stability(ACPS): A new generation of pillar design software

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International Journal of Mining Science and Technology 2019年第1期29卷 87-91页

作者： Christopher Mark Zach Agioutantis Technical Support Mine Safety and Health Administration Department of Mining Engineering University of Kentucky

Thirty years ago, the analysis of longwall pillar stability(ALPS) inaugurated a new era in coal pillar design.ALPS was the first empirical pillar design technique to consider the abutment loads that arise from full extraction, and the first to be calibrated using an extensive database of longwall mining case histories.ALPS was followed by the analysis of retreat mining stability(ARMPS) and the analysis of multiple seam stability(AMSS). These methods incorporated other innovations, including the coal mine roof rating(CMRR), the Mark-Bieniawski pillar strength formula, and the pressure arch loading model. They also built upon ever larger case history databases and employed more sophisticated statistical methods.Today, these empirical methods are used in nearly every underground coal mine in the US. However,the piecemeal manner in which these methods have evolved resulted in some weaknesses. For example,in certain situations, it may not be obvious which program is the best to use. Other times the results from the different programs are not entirely consistent with each other. The programs have also not been updated for several years, and some changes were necessary to keep pace with new developments in mining practice. The analysis of coal pillar stability(ACPS) now integrates all three of the older software packages into a single pillar design framework. ACPS also incorporates the latest research findings in the field of pillar design, including an expanded multiple seam case history data base and a new method to evaluate room and pillar panels containing multiple rows of pillars left in place during pillar recovery.ACPS also includes updated guidance and warnings for users and features upgraded help files and graphics.

关键词： Pillar design Ground control Stability Empirical methods

New developments in control design techniques of logical control networks

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Frontiers of Information Technology & Electronic Engineering 2020年第2期21卷 220-233页

作者： Xiang-shan KONG Shu-ling WANG Hai-tao LI Fuad E.ALSAADI School of Mathematics and Statistics Shandong Normal UniversityJirian 250014China Department of Electrical and Computer Engineering King Abdulaziz UniversityJeddah 21589Saudi Arabia

The control design problem plays a fundamental role in the study of logical control networks(LCNs).This paper presents a detailed survey on new developments in control design techniques of LCNs.First,some preliminary results on the semi-tensor product method and LCNs are reviewed.Then,we move on to some new developments for control design techniques of LCNs,including the reachable set approach,the pinning control technique,the control Lyapunov function approach,the event-triggered control technique,and the sampled-data control technique.Finally,an illustrative example is given to demonstrate the effectiveness of these techniques.

关键词： Logical control network Control design Semi-tensor product of matrices

User-friendly finite element design of main entries, barrier pillars,and bleeder entries

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International Journal of Mining Science and Technology 2018年第1期28卷 3-10页

作者： William G.Pariseau Mark K.Larson Heather E.Lawson Douglas R.Tesarik Department of Mining Engineering University of Utah Spokane Mining Research Division NIOSH

This contribution describes development and application of a user-friendly finite element program,UT3PC, to address three important problems in underground coal mine design:(1) safety of main entries,(2) barrier pillar size needed for entry protection, and(3) safety of bleeder entries during the advance of an adjacent longwall panel.While the finite element method is by far the most popular engineering design tool of the digital age, widespread use by the mining community has been impeded by the relatively high cost of and the need for lengthy specialized training in numerical methods.Implementation of UT3PC overcomes these impediments in three easy steps.First, a material properties file is prepared for the considered site.Next, mesh generation is automatic through an interactive process.A third and last step is simply execution of the program.Examples using data from several western coal mines illustrate the ease of using the application for analysis of main entries, barrier pillars, and bleeder entry safety.

关键词： Finite element Coal Mine layout design Main entries Barrier pillars Bleeder entries

Coal pillar design when considered a reinforcement problem rather than a suspension problem

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International Journal of Mining Science and Technology 2018年第1期28卷 11-19页

作者： Russell Frith Guy Reed Mine Advice Pty Ltd New South Wales 2282Australia

Current coal pillar design is the epitome of suspension design.A defined weight of unstable overburden material is estimated, and the dimensions of the pillars left behind are based on holding up that material to a prescribed factor of safety.In principle, this is no different to early roadway roof support design.However, for the most part, roadway roof stabilisation has progressed to reinforcement, whereby the roof strata is assisted in supporting itself.This is now the mainstay of efficient and effective underground coal production.Suspension and reinforcement are fundamentally different in roadway roof stabilisation and lead to substantially different requirements in terms of support hardware characteristics and their application.In suspension, the primary focus is the total load-bearing capacity of the installed support and ensuring that it is securely anchored outside of the unstable roof mass.In contrast, reinforcement recognises that roof de-stabilisation is a gradational process with ever-increasing roof displacement magnitude leading to ever-reducing stability.Key roof support characteristics relate to such issues as system stiffness, the location and pattern of support elements and mobilising a defined thickness of the immediate roof to create(or build) a stabilising strata beam.The objective is to ensure that horizontal stress is maintained at a level that prevents mass roof collapse.This paper presents a prototype coal pillar and overburden system representation where reinforcement, rather than suspension, of the overburden is the stabilising mechanism via the action of in situ horizontal stresses.Established roadway roof reinforcement principles can potentially be applied to coal pillar design under this representation.The merit of this is evaluated according to failed pillar cases as found in a series of published databases.Based on the findings, a series of coal pillar system design considerations for bord and pillar type mine workings are provided.This potentially allows a more flexible approach t

关键词： Coal pillar design Overburden stability Rock reinforcement Bord and pillar mining

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design

明日风尚 2014年第19期 49-51页

作者：任亚鹏

深邃的海之桌01Duffy Iondon是一家位于英国伦敦的家具设计事务所,在2002年由布莱顿大学毕业的Christopher Duffy创办。他们的设计理念是结合艺术与功能以及优秀的灵感来展现几何的不凡视觉效果,同时将那些有趣的设计概念转化为优质的... 详细信息

深邃的海之桌01Duffy Iondon是一家位于英国伦敦的家具设计事务所,在2002年由布莱顿大学毕业的Christopher Duffy创办。他们的设计理念是结合艺术与功能以及优秀的灵感来展现几何的不凡视觉效果,同时将那些有趣的设计概念转化为优质的产品。例如在他们之前的作品中,"Shadow Chair"像是一把只有两条腿的靠背椅,但事实上是由造型酷似椅子投影的基座支撑。此外,看起来像是用飘浮的气球托起的"The UP

关键词：布莱顿设计事务所概念转化 Shadow design 颜色信息扎哈建筑石材建筑设计领域哈

Aerodynamic optimization design of general parameters for cycloidal propeller in hover based on surrogate model

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航空动力学报 2019年第8期34卷 1741-1750页

作者： ZENG Jianan ZHU Qinghua WANG Kun ZHU Zhenhua SHEN Suiyuan College of Aeronautics Nanjing University of Aeronautics and Astronautics

A surrogate-model-based aerodynamic optimization design method for cycloidal propeller in hover was proposed,in order to improve its aerodynamic efficiency,and analyze the basic criteria for its aerodynamic optimization design.The reliability and applicability of overset mesh method were verified.An optimization method based on Kriging surrogate model was proposed to optimize the geometric parameters for cycloidal propeller in hover with the use of genetic algorithm.The optimization results showed that the thrust coefficient was increased by 3.56%,the torque coefficient reduced by 12.05%,and the figure of merit(FM)increased by 19.93%.The optimization results verified the feasibility of this design idea.Although the optimization was only carried out at a single rotation speed,the aerodynamic efficiency was also significantly improved over a wide range of rotation speeds.The optimal configuration characteristics for micro and small-sized cycloidal propeller were:solidity of 0.2-0.22,maximum pitch angle of 25°-35°,pitch axis locating at 35%-45% of the blade chord length.

关键词： cycloidal propeller aerodynamic shape optimization key design parameters surrogate-based optimization dynamic overset mesh