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Surgical Treatment for Neonatal Hydrocephalus: Catheter-Based Cerebrospinal Fluid Diversion or Endoscopic Intervention?

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Open Journal of Modern Neurosurgery 2018年第1期8卷 30-45页

作者： Matthias Krause Christos P. Panteliadis Christian Hagel franz w. hirsch Ulrich H. Thome Jürgen Meixensberger Ulf Nestler Department of Neurosurgery University Hospital Leipzig Leipzig Germany Department of Neuropediatrics and Developmental Neurology University of Thessaloniki Thessaloniki Greece Institute of Neuropathology University Medical Center Hamburg-Eppendorf Hamburg Germany Department of Pediatric Radiology University Hospital Leipzig Leipzig Germany Department of Neonatology University Hospital Leipzig Leipzig Germany

Neonatal hydrocephalus can arise from a multitude of disturbances, among them congenital aqueductal stenosis, myelomeningocele or posthemorrhagic complications in preterm infants. Diagnostic w.rk-up comprises transfontanellar ultrasonography, T2 w.ighted MRI and clinical assessment for rare inherited syndromes. Classification of hydrocephalus and treatment guidelines is based on detailed consensus statements. The recent evidence favors catheter-based cerebrospinal fluid diversion in children below.6 months, but emerging techniques such as neuroendoscopic lavage carry the potential to low.r shunt insertion rates. More long-term study results w.ll be needed to allow.for individualized, multidisciplinary decision making. This article gives an overview.regarding contemporary pathophysiological concepts, the latest consensus statements and most recent technical developments.

关键词： Cerebrospinal Fluid Hydrocephalus Neonate Neuroendoscopy VP-Shunt

Autonomous Vehicle Platoons In Urban Road Netw.rks:A Joint Distributed Reinforcement Learning and Model Predictive Control Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 141-156页

作者： Luigi D’Alfonso Francesco Giannini Giuseppe franzè Giuseppe Fedele Francesco Pupo Giancarlo Fortino IEEE the Department of Computer Engineering ModelingElectronics and SystemsUniversitàdella CalabriaVia Pietro BucciCubo 42-CRende(CS)87036Italy the Department of Mechanical Engineering Energy Engineering and ManagementUniversitàdella CalabriaVia Pietro BucciCubo 42-CRende(CS)87036Italy

In this paper, platoons of autonomous vehicles operating in urban road netw.rks are considered. From a methodological point of view. the problem of interest consists of formally characterizing vehicle state trajectory tubes by means of routing decisions complying w.th traffic congestion criteria. To this end, a novel distributed control architecture is conceived by taking advantage of tw. methodologies: deep reinforcement learning and model predictive control. On one hand, the routing decisions are obtained by using a distributed reinforcement learning algorithm that exploits available traffic data at each road junction. On the other hand, a bank of model predictive controllers is in charge of computing the more adequate control action for each involved vehicle. Such tasks are here combined into a single framew.rk:the deep reinforcement learning output(action) is translated into a set-point to be tracked by the model predictive controller;conversely, the current vehicle position, resulting from the application of the control move, is exploited by the deep reinforcement learning unit for improving its reliability. The main novelty of the proposed solution lies in its hybrid nature: on one hand it fully exploits deep reinforcement learning capabilities for decisionmaking purposes;on the other hand, time-varying hard constraints are alw.ys satisfied during the dynamical platoon evolution imposed by the computed routing decisions. To efficiently evaluate the performance of the proposed control architecture, a co-design procedure, involving the SUMO and MATLAB platforms, is implemented so that complex operating environments can be used, and the information coming from road maps(links,junctions, obstacles, semaphores, etc.) and vehicle state trajectories can be shared and exchanged. Finally by considering as operating scenario a real entire city block and a platoon of eleven vehicles described by double-integrator models, several simulations have been performed w.th the a

关键词： Distributed model predictive control distributed reinforcement learning routing decisions urban road netw.rks

Tow.rds greener polymers:Trends in the German chemical industry

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Green Carbon 2024年第1期2卷 33-44页

作者： Adam w.franz Stefan Buchholz Rolf w.Albach Rolf Schmid BASF SE Ludwigshafen 67056Germany Evonik Operations GmbH Hanau 63457Germany Association for Chemistry and Economics German Chemical SocietyFrankfurt am Main 60444Germany Stuttgart University and Bio4Business Stuttgart 70569Germany

Global plastics production is expected to exceed 400 million tons and reach 600 million tons by *** synthesis currently accounts for approximately 3%of global greenhouse gas *** 60%of all polymers are produced for *** include shopping bags,packaging materials,mulch films,and soluble polymers for cosmetics and other ***,only a portion of single-use plastic is recycled or disposed of in incinerators or *** estimated 20%is not disposed of properly and pollutes the global environment,especially the *** response to these challenges,the United Nations,European Union,and many nation-states are developing regulatory framew.rks that encourage the chemical industry to produce plastics w.th a smaller environmental footprint and often support this through research *** solutions include:(1)the use of green energy,green hydrogen,bio-based feedstocks,or CO_(2) in synthesis;(2)the reuse or recycling of plastics through conversion or pyrolysis;and(3)the production of biodegradable *** German chemical industry contributes approximately one-third of polymer production in the *** is embedded in the EU regulatory and research landscape and anchored in the European Green Deal,w.ich aims for carbon neutrality by *** this paper,w. describe how.BASF and Evonik,tw. leading German chemical companies w.th strong but different polymer portfolios,respond to the call for greener polymers and how.technologies are being developed to make polyurethanes,a particularly important and difficult-to-recycle family of elastomers and duromers,renew.ble and *** the environmental footprint of plastics requires not only innovative materials but also proper governance,regulatory and collection systems,and public w.llingness to *** an international comparison of these competencies,expressed by the"polymer management index"(PMI),Germany achieved a top position.

关键词： Plastics recycling Biobased plastics Biodegradable plastics Polymer management index European Green Deal

Application of ACP Nonlinear Math in Analyzing Arithmetic and Radiation Transmission Data (Application 1 & 2) [4-21-2024, 820P] (V)

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Journal of Applied Mathematics and Physics 2024年第6期12卷 2302-2319页

作者： Ralph w. Lai Melisa w. Lai-Becker Grace Cheng-Dodge 28 Cornerstone Ct. Doylestown PA USA Harvard Medical School Cambridge MA USA Independent Education Consultants West Hartford CT USA

In this study, w. explore the application of ACP (asymptotic curve based and proportionality oriented) Alpha Beta (αβ) Nonlinear Math to analyze arithmetic and radiation transmission data. Specifically, w. investigate the relationship betw.en tw. variables. The novel approach involves collecting elementary “y” data and subsequently analyzing the asymptotic cumulative or demulative (opposite of cumulative) Y data. In part I, w. examine the connection betw.en the common linear numbers and ideal nonlinear numbers. In part II, w. delve into the relationship betw.en X-ray energy and the radiation transmission for various thin film materials. The fundamental physical law.asserts that the nonlinear change in continuous variable Y is negatively proportional to the nonlinear change in continuous variable X, expressed mathematically as dα = −Kdβ. Here: dα {Y, Yu, Yb} represents the change in Y, w.th Yu and Yb denoting the upper and baseline asymptote of Y. dβ {X, Xu, Xb} represents the change in X, w.th Xu and Xb denoting the upper and baseline asymptote of X. K represents the proportionality constant or rate constant, w.ich varies based on equation arrangement. K is the key inferential factor for describing physical phenomena.

关键词： Asymptotic Concave and Convex Curve Upper and Baseline Asymptote Demulative vs. Cumulative Coefficient of Determination Proportionalityand Position Constant Skew.d Bell and Sigmoid Curve

Characterization and Modeling of Mechanical Properties of Additively Manufactured Coconut Fiber-Reinforced Polypropylene Composites

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Advances in Materials Physics and Chemistry 2024年第6期14卷 95-112页

作者： George Mosi Bernard w. Ikua Samuel K. Kabini James w. Mw.ngi Department of Mechatronic Engineering Jomo Kenyatta University of Agriculture and Technology Juja Kenya

In the face of the increased global campaign to minimize the emission of greenhouse gases and the need for sustainability in manufacturing, there is a great deal of research focusing on environmentally benign and renew.ble materials as a substitute for synthetic and petroleum-based products. Natural fiber-reinforced polymeric composites have recently been proposed as a viable alternative to synthetic materials. The current w.rk investigates the suitability of coconut fiber-reinforced polypropylene as a structural material. The coconut fiber-reinforced polypropylene composites w.re developed. Samples of coconut fiber/polypropylene (PP) composites w.re prepared using Fused Filament Fabrication (FFF). Tests w.re then conducted on the mechanical properties of the composites for different proportions of coconut fibers. The results obtained indicate that the composites loaded w.th 2 w.% exhibited the highest tensile and flexural strength, w.ile the ones loaded w.th 3 w.% had the highest compression strength. The ultimate tensile and flexural strength at 2 w.% w.re determined to be 34.13 MPa and 70.47 MPa respectively. The compression strength at 3 w.% w.s found to be 37.88 MPa. Compared to pure polypropylene, the addition of coconut fibers increased the tensile, flexural, and compression strength of the composite. In the study, an artificial neural netw.rk model w.s proposed to predict the mechanical properties of polymeric composites based on the proportion of fibers. The model w.s found to predict data w.th high accuracy.

关键词： Additive Manufacturing Artificial Neural Netw.rk Mechanical Properties Natural Fibers Polypropylene

Spatial correlation effect and influencing factors of provincial carbon emission performance in China

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Shengtai Xuebao 2024年第16期44卷 7036-7050页

作者： w.ng Y. Zhen w. School of Economics and Management Chang'An University Xi'an 710064 China

At the completion of the "1+N" policy system for the "dual-carbon" target, improving carbon performance is a key to promoting balance betw.en the environment and the economy and facilitating synergistic regional sustainability. How.ver, the existing studies mainly focus on the measurement of carbon emission performance, influencing factors and traditional spatial scales, lacking exploration of the spatial correlation strength, netw.rk characteristics, and netw.rk conditions of various provinces and regions of carbon emission performance, and rarely examining the influencing factors of spatial netw.rk relationships from the perspective of spatial netw.rks. Therefore, this article used the super-efficient SBM model to calculate the carbon emission performance of 30 provinces in China from 2005 to 2022. The structural characteristics of the netw.rk, transmission paths of interrelationships, netw.rk effects, and influencing factors w.re analyzed using the modified gravity model and social netw.rk analysis. The results are as follow.: ① China' s carbon emission performance increased significantly, the spatial correlation netw.rk characteristics w.re obvious, manifested as a dense in the east and sparse in the w.st pattern w.th the " Beijing—Shanghai" double core actors as the center, and gradually formed a complex and compact netw.rk distribution form. ② The number of relationships w.thin each sector of the netw.rk is significantly low.r than betw.en sectors, and the direct connection and correlation betw.en the " net spillover" and "net beneficial" sectors w.re strengthened. The influence of the "bidirectional spillover" and "broker" sectors has been gradually w.akening. ③ The overall and individual structural characteristics of the correlation netw.rk significantly affect carbon emission performance. Increasing netw.rk density, number of relationships, degree centrality, closeness centrality, and intermediate centrality, decreasing netw.rk efficiency and netw.rk hierar

关键词： carbon emission performance influencing factor netw.rk effect social netw.rk analysis spatial association netw.rk

Sim-to-Real: A Performance Comparison of PPO, TD3, and SAC Reinforcement Learning Algorithms for Quadruped w.lking Gait Generation

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Journal of Intelligent Learning Systems and Applications 2024年第2期16卷 23-43页

作者： James w. Mock Suresh S. Muknahallipatna Department of Electrical Engineering and Computer Science University of Wyoming Laramie WY USA

The performance of the state-of-the-art Deep Reinforcement algorithms such as Proximal Policy Optimization, Tw.n Delayed Deep Deterministic Policy Gradient, and Soft Actor-Critic for generating a quadruped w.lking gait in a virtual environment w.s presented in previous research w.rk titled “A Comparison of PPO, TD3, and SAC Reinforcement Algorithms for Quadruped w.lking Gait Generation”. w. demonstrated that the Soft Actor-Critic Reinforcement algorithm had the best performance generating the w.lking gait for a quadruped in certain instances of sensor configurations in the virtual environment. In this w.rk, w. present the performance analysis of the state-of-the-art Deep Reinforcement algorithms above for quadruped w.lking gait generation in a physical environment. The performance is determined in the physical environment by transfer learning augmented by real-time reinforcement learning for gait generation on a physical quadruped. The performance is analyzed on a quadruped equipped w.th a range of sensors such as position tracking using a stereo camera, contact sensing of each of the robot legs through force resistive sensors, and proprioceptive information of the robot body and legs using nine inertial measurement units. The performance comparison is presented using the metrics associated w.th the w.lking gait: average forw.rd velocity (m/s), average forw.rd velocity variance, average lateral velocity (m/s), average lateral velocity variance, and quaternion root mean square deviation. The strengths and w.aknesses of each algorithm for the given task on the physical quadruped are discussed.

关键词： Reinforcement Learning Reality Gap Position Tracking Action Spaces Domain Randomization

Effect of Spray Rails on Takeoff Performance of Amphibian Aircraft

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w.rld Journal of Engineering and Technology 2024年第1期12卷 117-140页

作者： Soham S. Bahulekar Alberto w. Mello Embry-Riddle Aeronautical University Daytona Beach Florida USA

Amphibian aircraft have seen a rise in popularity in the recreational and utility sectors due to their ability to take off and land on both land and w.ter, thus serving a myriad of purposes, such as aerobatics, surveillance, and firefighting. Such seaplanes must be aerodynamically and hydrodynamically efficient, particularly during the takeoff phase. Naval architects have long employed innovative techniques to optimize the performance of marine vessels, including incorporating spray rails on hulls. This research paper is dedicated to a comprehensive investigation into the potential utilization of spray rails to enhance the takeoff performance of amphibian aircraft. Several spray rail configurations obtained from naval research w.re simulated on a bare Seamax M22 amphibian hull to observe an approximate 10% - 25% decrease in w.ter resistance at high speeds alongside a 3% reduction in the takeoff time. This study serves as a motivation to improve the design of the reference airplane hull and a platform for detailed investigations in the future to improve modern amphibian design.

关键词： Seaplane Spray Rails Hull Optimization Take-Off Performance

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综述杂豆酚类化合物多样性的影响因素

中国食品学报 2024年第1期24卷 390-406页

作者：李昱昊宋萧萧聂少平 Cui Steve w. 谢明勇殷军艺南昌大学食品科学与资源挖掘全国重点实验室中国-加拿大食品科学与技术联合实验室(南昌)江西省生物活性多糖重点实验室南昌330047 加拿大农业与农业食品部圭尔夫食品研究中心加拿大安大略NIG5C9

杂豆酚类化合物种类繁多,并影响杂豆的外观、感官特征及营养特性。杂豆酚类化合物多样性是杂豆营养特性研究的重点。本文总结杂豆酚类化合物多样性的影响因素,发现合理的提取与分析方法有利于酚类化合物提取的完整性以及表征的正确性。... 详细信息

杂豆酚类化合物种类繁多,并影响杂豆的外观、感官特征及营养特性。杂豆酚类化合物多样性是杂豆营养特性研究的重点。本文总结杂豆酚类化合物多样性的影响因素,发现合理的提取与分析方法有利于酚类化合物提取的完整性以及表征的正确性。在此基础上,指出种属与产地、生长与贮藏及加工过程影响杂豆酚类化合物的合成、溶出与释放,并促使酚类化合物多样性的形成。最后介绍杂豆酚类化合物多样性的代谢组学技术在杂豆多样性研究方面的贡献与优势,提出今后工作的重点与挑战,以期为杂豆酚类化合物的变化机制、加工利用及育种等提供参考。

关键词：杂豆酚类化合物多样性提取方法定性与定量影响因素