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CRYSTALLIZATION OF BLENDS OF AN ASYMMETRIC POLY(OXYETHYLENE)-b-POLY(OXYBUTYLENE) BLOCK COPOLYMER WITH POLY(OXYBUTYLENE)

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Chinese journal of Polymer Science 2004年第5期22卷 477-483页

作者：徐君庭 Guo-dongLiang Shao-minMai a.j.ryan DepartmentofPolymerScience＆Engineering ZhejiangUm＇versity.Hangzhou310027China ChemistryDepartment TheUniversityofSheffieldSheffieldS37HFUK DepartmentofPolymerScience＆Engineering ZhejiangUm＇versity.Hangzhou310027China

An oxyethylene/oxybutylene block copolymer with asymmetric volume fraction (E115B105) was blended with oxybutylene homopolymer (Bh) at different volume fractions of the block Crystallization behavior of the blends was studied and was compared with that of the blends from a symmetric block copolymer (E114B56). It was found that the crystallization temperature of E115B103/B28 blend is lower than that of the blends from symmetric block copolymer. For the blend with = 0.30 breakout crystallization with an Avrami exponent n 3.0 is observed. At = 0.22 the blend exhibits a variable crystallization behavior: confined crystallization with n 1.0 at lower crystallization temperatures but breakout crystallization at high crystallization temperatures. For the blend with = 0.14 and sphere morphology confined crystallization occurs at all crystallization temperatures studied. When compared with the blends from symmetric block copolymer, confined crystallization occurs more easily in the E115B103/B28 blends. The SAXS results agree with the isothermal crystallization kinetics. Deformation of the confined crystalline block is observed in the blend with =0.14 and mixed lamellar and cylinder morphologies in the blend with = 0.22.

关键词： Crystallization Block copolymer Blend Confinement

Direct-to-indirect mapping for optimal low-thrust trajectories

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Astrodynamics 2024年第1期8卷 27-46页

作者： David Ottesen ryan P.Russell Department of Aerospace Engineering and Engineering Mechanics The University of Texas at AustinAustinTexas78712USA

Optimal,many-revolution spacecraft trajectories are challenging to solve.A connection is made for a class of models between optimal direct and indirect *** transfers that minimize thrust-acceleration-squared,primer vector theory maps direct,many-impulsive-maneuver trajectories to the indirect,continuous-thrust-acceleration *** mapping algorithm is independent of how the direct solution is obtained and requires only a solver for a boundary value problem and its partial derivatives.A Lambert solver is used for the two-body problem in this *** mapping is simple because the impulsive maneuvers and co-states share the same linear space around an optimal *** numerical results,the direct coast-impulse solutions are demonstrated to converge to the indirect continuous solutions as the number of impulses and segments *** two-body design space is explored with a set of three many-revolution,many-segment examples changing semimajor axis,eccentricity,and *** first two examples involve a small change to either semimajor axis or eccentricity,and the third example is a transfer to geosynchronous *** a single processor,the optimization runtime is seconds to minutes for revolution counts of 10 to 100,and on the order of one hour for examples with up to 500 *** of these thrust-acceleration-squared solutions are good candidates to start a homotopy to a higher-fidelity minimization problem with practical constraints.

关键词： direct optimization indirect optimization impulsive maneuvers Lambert's problem two-body dynamics primer vectortheory

Parallel intelligent education with ChatGPT

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Frontiers of Information Technology & Electronic Engineering 2024年第1期25卷 12-18页

作者： jiacun WANG Ying TANG ryan HARE Fei-Yue WANG Department of Computer Science and Software Engineering Monmouth UniversityNew Jersey 07764USA Department of Electrical and Computer Engineering Rowan UniversityNew Jersey 08028USA Institute of Automation Chinese Academy of SciencesBeijing 100190China

This paper presents a framework for parallel intelligent education that involves physical and virtual learning for a personalized learning *** especially focus on Chat Generative Pre-trained Transformer(ChatGPT)owing to its considerable potential to supplement regular class *** address the strengths and weaknesses of learning with ***,we discuss the challenges and solutions of the proposed parallel intelligent education with ChatGPT.

关键词： education GPT intelligent

Management of gestational diabetes mellitus via nutritional interventions:The relevance of gastric emptying

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World journal of Diabetes 2024年第7期15卷 1394-1397页

作者： Wei-Kun Huang ryan j jalleh Christopher K Rayner Tong-Zhi Wu Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health The University of AdelaideAdelaide 5000Australia Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health The University of Adelaide and Department of Gastroenterology and HepatologyRoyal Adelaide HospitalAdelaide 5000Australia

Gestational diabetes mellitus(GDM)represents one of the most common medical complications of pregnancy and is important to the well-being of both mothers and offspring in the short and long *** intervention remains the mainstay for the management of *** efficacy of nutritional approaches(*** restriction and small frequent meals)to improving the maternal-neonatal outcomes of GDM was attested to by Chinese population data,discussed in two articles in recent issues of this ***,a specific focus on the relevance of postprandial glycaemic control was *** rather than fasting hyperglycaemia often represents the predominant manifestation of disordered glucose homeostasis in Chinese women with *** is now increasing appreciation that the rate of gastric emptying,which controls the delivery of nutrients for digestion and absorption in the small intestine,is a key determinant of postprandial glycaemia in both health,type 1 and 2 *** remains to be established whether gastric emptying is abnormally rapid in GDM,particularly among Chinese women,thus contributing to a predisposition to postprandial hyperglycaemia,and if so,how this influences the therapeutic response to nutritional *** is essential that we understand the role of gastric emptying in the regulation of postprandial glycaemia during pregnancy and the potential for its modulation by nutritional strategies in order to improve postprandial glycaemic control in GDM.

关键词： Gastric emptying Postprandial glycaemia Diet Nutritional interventions Gestational diabetes mellitus

Machine learning-guided accelerated discovery of structure-property correlations in lean magnesium alloys for biomedical applications

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journal of Magnesium and Alloys 2024年第6期12卷 2267-2283页

作者： Sreenivas Raguraman Maitreyee Sharma Priyadarshini Tram Nguyen ryan McGovern Andrew Kim Adam j.Griebel Paulette Clancy Timothy P.Weihs Department of Materials Science and Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Hopkins Extreme Materials Institute Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Department of Chemical and Biomolecular Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Translational Tissue Engineering Center Johns Hopkins School of Medicine400 N BroadwayBaltimore21231MDU.S.A Department of Biomedical Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Research and Development Fort Wayne Metals Research ProductsLLC9609 Ardmore AveFort Wayne46809INU.S.A Department of Mechanical Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A

Magnesium alloys are emerging as promising alternatives to traditional orthopedic implant materials thanks to their biodegradability,biocompatibility,and impressive mechanical ***,their rapid in-vivo degradation presents challenges,notably in upholding mechanical integrity over *** study investigates the impact of high-temperature thermal processing on the mechanical and degradation attributes of a lean Mg-Zn-Ca-Mn alloy,*** rapid,cost-efficient characterization methods like X-ray diffraction and optical microscopy,we swiftly examine microstructural changes post-thermal *** Pearson correlation coefficient analysis,we unveil the relationship between microstructural properties and critical targets(properties):hardness and corrosion ***,leveraging the least absolute shrinkage and selection operator(LASSO),we pinpoint the dominant microstructural factors among closely correlated *** findings underscore the significant role of grain size refinement in strengthening and the predominance of the ternary Ca_(2)Mg_(6)Zn_(3)phase in corrosion *** suggests that achieving an optimal blend of strength and corrosion resistance is attainable through fine grains and reduced concentration of ternary *** thorough investigation furnishes valuable insights into the intricate interplay of processing,structure,and properties in magnesium alloys,thereby advancing the development of superior biodegradable implant materials.

关键词： Magnesium alloys Machine learning Corrosion Mechanical properties Rapid characterization

Exploiting blockchain for dependable services in zero-trust vehicular networks

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Frontiers of Computer Science 2024年第2期18卷 157-166页

作者： Min HAO Beihai TAN Siming WANG Rong YU ryan Wen LIU Lisu YU School of Automation Guangdong University of TechnologyGuangzhou 510006China School of Integrated Circuits Guangdong University of TechnologyGuangzhou 510006China School of Navigation Wuhan University of TechnologyWuhan 430063China School of Information Engineering Nanchang UniversityNanchang 330031China

The sixth-generation(6G)wireless communication system is envisioned be cable of providing highly dependable services by integrating with native reliable and trustworthy ***-trust vehicular networks is one of the typical scenarios for 6G dependable *** the technical framework of vehicle-and-roadside collaboration,more and more on-board devices and roadside infrastructures will communicate for information *** reliability and security of the vehicle-and-roadside collaboration will directly affect the transportation *** a zero-trust vehicular environment,to prevent malicious vehicles from uploading false or invalid information,we propose a malicious vehicle identity disclosure approach based on the Shamir secret sharing ***,a two-layer consortium blockchain architecture and smart contracts are designed to protect the identity and privacy of benign vehicles as well as the security of their private *** that,in order to improve the efficiency of vehicle identity disclosure,we present an inspection policy based on zero-sum game theory and a roadside unit incentive mechanism jointly using contract theory and subjective logic *** verify the performance of the entire zero-trust solution through extensive simulation *** the premise of protecting the vehicle privacy,our solution is demonstrated to significantly improve the reliability and security of 6G vehicular networks.

关键词： sixth-generation(6G) zero-trust block-chain vehicular networks privacy preservation

Millimetric devices for nerve stimulation:a promising path towards miniaturization

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Neural Regeneration Research 2024年第8期19卷 1702-1706页

作者： ryan M.Dorrian Anna V.Leonard Antonio Lauto Spinal Cord Injury Research Group School of BiomedicineThe University of AdelaideAdelaideSAAustralia School of Science Western Sydney UniversityPenrithNSWAustralia

Nerve stimulation is a rapidly developing field,demonstrating positive outcomes across several *** potential benefits,current nerve stimulation devices are large,complicated,and are powered via implanted pulse *** facto rs necessitate invasive surgical implantation and limit potential *** nerve stimulation devices to millimetric sizes would make these interventions less invasive and facilitate broader therapeutic ***,device miniaturization presents a serious engineering *** review presents significant advancements from several groups that have overcome this challenge and developed millimetricsized nerve stimulation *** are based on antennas,mini-coils,magneto-electric and optoelectronic materials,or receive ultrasound *** highlight key design elements,findings from pilot studies,and present several considerations for future applications of these devices.

关键词： biomedical engineering deep brain stimulation electrical engineering electrical stimulation neuromodulation peripheral nerve stimulation

The Artificial Disc Nucleus and Other Strategies for Replacement of the Nucleus Pulposus:Past,Present and Future Designs for an Emerging Surgical Solution

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Engineered Regeneration

Engineered Regeneration 2024年第2期5卷 269-281页

作者： Greg Sacks Vincent DeStefano Claire Parker ryan Lebens Harry Mushlin Renaissance School of Medicine at Stony Brook University Stony BrookNYUSA

Nucleus Pulposus(NP)Replacement is a developing surgical methodology for the treatment of pathology related to degeneration of intervertebral discs(IVDs).This article provides necessary context regarding the patholo-gies treated with this technology,the biomechanical structure and function of the IVD,and the procedures this technology aims to ***,it provides an overview and discussion of commercial and experimental preformed and in situ curing prosthesis designs reported in the scientific literature and summarizes the results of biomechanical and clinical studies evaluating their *** and updated information on the most recent research into NP replacement with novel hydrogel and tissue engineering(TE)strategies is *** of the NP allows for potential improvement in the treatment of degenerative spinal pathologies through minimally invasive surgical techniques.

关键词： Nucleus Pulposus Intradiscal Prosthesis Hydrogel Artificial Disc Implant Spine Surgery

Machine learning for predicting the outcome of terminal ballistics events

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Defence Technology（防务技术） 2024年第1期31卷 14-26页

作者： Shannon ryan Neeraj Mohan Sushma Arun Kumar AV julian Berk Tahrima Hashem Santu Rana Svetha Venkatesh Applied Artificial Intelligence Institute(A2I2) Deakin University75 Pigdons RdWaurn PondsVIC3216Australia

Machine learning(ML) is well suited for the prediction of high-complexity,high-dimensional problems such as those encountered in terminal *** evaluate the performance of four popular ML-based regression models,extreme gradient boosting(XGBoost),artificial neural network(ANN),support vector regression(SVR),and Gaussian process regression(GP),on two common terminal ballistics’ problems:(a)predicting the V50ballistic limit of monolithic metallic armour impacted by small and medium calibre projectiles and fragments,and(b) predicting the depth to which a projectile will penetrate a target of semi-infinite *** achieve this we utilise two datasets,each consisting of approximately 1000samples,collated from public release *** demonstrate that all four model types provide similarly excellent agreement when interpolating within the training data and diverge when extrapolating outside this *** extrapolation is not advisable for ML-based regression models,for applications such as lethality/survivability analysis,such capability is *** circumvent this,we implement expert knowledge and physics-based models via enforced monotonicity,as a Gaussian prior mean,and through a modified loss *** physics-informed models demonstrate improved performance over both classical physics-based models and the basic ML regression models,providing an ability to accurately fit experimental data when it is available and then revert to the physics-based model when *** resulting models demonstrate high levels of predictive accuracy over a very wide range of projectile types,target materials and thicknesses,and impact conditions significantly more diverse than that achievable from any existing analytical *** with numerical analysis tools such as finite element solvers the ML models run orders of magnitude *** provide some general guidelines throughout for the development,application,and reporting of ML models in terminal ballist

关键词： Machine learning Artificial intelligence Physics-informed machine learning Terminal ballistics Armour