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Controllable preparation of phosphonium-based polymeric ionic liquids as highly selective nanocatalysts for the chemical conversion of CO₂ with epoxides

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GREEN CHEMISTRY 2017年第9期19卷 2184-2193页

作者： Liu, Ying Cheng, Weiguo Zhang, Yanqiang Sun, Jian Zhang, Suojiang Chinese Acad Sci Inst Proc Engn Beijing Key Lab Ionic Liquids Clean Proc State Key Lab Multiphase Complex Syst Beijing 100190 Peoples R China

Phosphonium-based polymeric ionic liquids (PILs) have been prepared in a controlled way by using a microfluidic technique within an improved membrane microdevice. Using this method, the average diameter sizes of the particles could be tuned from 6.4 to 375 nm through varying the dispersed phase flow rates from 1.0 to 7.0 mL min(-1). The nanoparticles were characterized by FTIR, SEM, HRTEM, EDS, TGA and ICP, and their catalytic properties were estimated in the cycloaddition of CO2 with epoxides. It was found they could deliver good to excellent yields with selectivities of more than 99%. 1-Bromoacrylic acid-decorated nanoparticles (NPILs-BPA) were especially effective. Additionally, the activity displayed obvious size-dependence, increasing for the smaller particles, and the particles were stable when recycled seven times, retaining their catalytic activity and selectivity. Meanwhile, the ability of NPILs-BPA to provide carboxylic acid groups and act as a hydrogen bonding donor to activate the ring-opening of epoxides was tested by in situ FTIR. This work provides a continuous, simple method for the preparation of PILs with controlled nanosizes, and offers the potential for scale-up and throughput in industrial applications.

关键词： Ionic liquids Epoxy Compounds cycloaddition iterative closest point algorithm Carbon Dioxide Industrial applications CARBOXYLIC ACID GROUP hydrogen bonds Inductively coupled plasma polymers Flow rates

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Pose Estimation for Spacecraft Relative Navigation Using Model-Based algorithms

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IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS 2017年第1期53卷 431-447页

作者： Opromolla, Roberto Fasano, Giancarmine Rufino, Giancarlo Grassi, Michele Univ Naples Federico II Dept Ind Engn I-8080125 Naples Italy

This paper presents the performance assessment of innovative model-based algorithms developed for pose estimation of uncooperative targets by processing sparse three-dimensional point clouds. This topic is of interest in the framework of advanced space applications, e.g., on-orbit servicing and active debris removal, which require a chaser spacecraft to execute autonomous relative navigation maneuvers in close-proximity of a space target. Both the problems of pose acquisition and tracking are addressed. The former one is carried out by combining the concepts of principal component analysis and template matching in order to limit both the computational effort and the amount of on-board data storage compared with traditional approaches. The latter is entrusted to a customized implementation of the iterative closest point algorithm, which adopts multiple model-measurement matching strategies as well as a refinement step, in order to respectively increase robustness and accelerate algorithm convergence. Also, safe transition from acquisition to tracking is implemented by means of autonomous detection of failures of the pose acquisition algorithm. The performance of the proposed techniques is investigated by means of numerical simulations in which the operation of an active LIDAR system as well as the target-chaser relative dynamics are realistically reproduced. Results demonstrate algorithms' effectiveness over a wide range of relative pose conditions and dealing with targets of variable size and shape, in spite of considerable sparseness of the measured datasets.

关键词： Databases Feature extraction iterative closest point algorithm Laser radar LIDAR Pose estimation principal component analysis (PCA) spacecraft relative navigation Target tracking template matching Three-dimensional displays uncooperative target

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KPPF: Keypoint-based point-Pair-Feature for scalable automatic global registration of large RGB-D scans 16

KPPF: Keypoint-based Point-Pair-Feature for scalable automat...

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16th IEEE International Conference on Computer Vision (ICCV)

作者： Malleus, L. Fisichella, T. Lingrand, D. Precioso, F. Gros, N. Noutary, Y. Robert, L. Samoun, L. Univ Cote Dazur CNRS I3S Nice France Autodesk Sophia Antipolis France

ISBN: (纸本)9781538610343

One of the most important challenges in the field of 3D data processing is to be able to reconstruct a complete 3D scene with a high accuracy from several captures. Usually this process is achieved through two main phases: a coarse, or rough, alignment step then a fine alignment. In this article we propose an automatic scalable global registration method (i.e. without arbitrary pose of the sensor) under the following constraints: markerless, very large scale data (several, potentially many millions of points per scans), little overlap between scans, for more than two or three dozens of scans, without a priori knowledge on the 6 degrees of freedom. Here we only address the coarse alignment, and consider the fine alignment step tackled by dedicated existing approaches such as iterative closest point (ICP) [3]. We evaluate thoroughly our method on our own dataset of 33 real large scale scans of an indoor building. The data presents some pairs of scans with very little overlap, architectural challenges (a patio and a rotunda open through several levels of the buildings, etc), several millions of points per scan. We will make this dataset public as part of a benchmark available for the community. We have thus evaluated the accuracy of our method, the scalability to the initial amount of points and the robustness to occlusions, little scan overlap and architectural challenges.

关键词： Three-dimensional displays Detectors Clustering algorithms iterative closest point algorithm Feature extraction

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Industrial Cyberphysical Systems

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IEEE INDUSTRIAL ELECTRONICS MAGAZINE 2017年第1期11卷 6-16页

作者： Colombo, Armando W. Karnouskos, Stamatis Kaynak, Okyay Shi, Yang Yin, Shen Schneider Elect Rueil Malmaison France Univ Appl Sci Emden Leer Inst Ind Informat Automat & Robot Emden Germany Bogazici Univ Istanbul Turkey Harbin Inst Technol Harbin Peoples R China Univ Victoria Dept Mech Engn Victoria BC V8W 2Y2 Canada Harbin Inst Technol Sch Astronaut Harbin Peoples R China

Cyberphysical systems (CPSs) are perceived as the pivotal enabler for a new era of real-time Internet-based communication and collaboration among value-chain participants, e.g., devices, systems, organizations, and humans. The CPS utilization in industrial settings is expected to revolutionize the way enterprises conduct their business from a holistic viewpoint, i.e., from shop-floor to business interactions, from suppliers to customers, and from design to support across the whole product and service lifecycle. Industrial CPS (ICPSs) blur the fabric of cyber (including business) and physical worlds and kickstart an era of systemwide collaboration and information-driven interactions among all stakeholders of the value chain. Therefore, ICPSs are expected to empower the transformation of industry and business at large to a digital, adaptive, networked, and knowledge-based industry with significant long-term impact on the economy, society, environment, and citizens.

关键词： iterative closest point algorithm Cyber-physical systems Collaboration Ecosystems Stakeholders Internet Industrial Internets Cyber-physical systems Stakeholders Ecosystem Business

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Fast Registration Methodology for Fastener Assembly of Large-Scale Structure

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IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS 2017年第1期64卷 717-726页

作者： Xu, Jing Chen, Rui Chen, Heping Zhang, Song Chen, Ken Tsinghua Univ State Key Lab Tribol Dept Mech Engn Beijing Key Lab Precis Ultraprecis Mfg Equipment Beijing 100084 Peoples R China Texas State Univ Ingram Sch Engn San Marcos TX 78666 USA Purdue Univ Sch Mech Engn W Lafayette IN 47907 USA

Fastener assembly is a tedious and time-consuming work because operators have to check assembly manuals and find right fastener for each hole. Hence, this paper aims to develop a three-dimensional (3-D) projection system that projects assembly instruction onto the work piece surface directly to guide operators to assemble. However, in order to project the instruction accurately, the corresponding part of the computer-aided design model of the physical scanned area needs to be attained through the rapid and accurate registration. In order to achieve this goal, first, a high-accuracy and rapid 3-D measurement system is developed;second, a fast registration method based on local multiscale geometric feature vector is proposed to accelerate the registration speed and improve the registration reliability. Experimental results demonstrate the measurement accuracy of the developed system, and verify the feasibility of the proposed registration method. Hence, the proposed method can lead to improved assembly efficiency and decreased error probability, making great contributions to large-scale structure assembly.

关键词： Augmented reality (AR) feature extraction iterative closest point algorithm pattern matching

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Precise 2D point Set Registration Using iterative closest algorithm and Correntropy

Precise 2D Point Set Registration Using Iterative Closest Al...

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International Joint Conference on Neural Networks

作者： Guanglin Xu Shaoyi Du Jianru Xue Institute of Artificial Intelligence and Robotics Xi'an Jiaotong University 710049 China

ISBN: (纸本)9781509006212

The iterative closest point (ICP) algorithm is fast and accurate for rigid point set registration, but it works badly when there are many outliers and noises in the point sets. This paper instead proposes a novel method based on the ICP algorithm to deal with this problem. Firstly, correntropy is introduced into the rigid registration problem and then a new energy function based on maximum correntropy criterion is proposed. After that, a new ICP algorithm based on correntropy is proposed, which performs well in dealing with rigid registration with noises and outliers. This new algorithm converges moronically from any given parameters, which is similar to the ICP algorithm. Experimental results demonstrate its accuracy and efficiency compared with the traditional ICP algorithm.

关键词： iterative closest point algorithm algorithm design and analysis Data models Two dimensional displays Robustness Euclidean distance Mathematical model iterative closest point algorithm algorithm design and analysis data models Euclidean distance Mathematical Model Inductively coupled plasma Noise Set of points Registration

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Comparative study of RGB-D sensors based on controlled displacements of a ground-truth model1

Comparative study of RGB-D sensors based on controlled displ...

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International Conference on Control, Automation, Robotics and Vision (ICARCV)

作者： Adrien Anxionnat Sandrine Voros Jocelyne Troccaz CNRS Univ. Grenoble Alpes Grenoble France

In the context of developing a pedagogical tool for teaching anatomy, the need for a comparative study between two RGB-D cameras has emerged. This paper addresses the assessment of the accuracy and precision of two RGB-D sensors (Carmine Primesense and Persee Orbbec) through two different experiments. The evaluation not only provides comparative results on the sensors performances but also aims at determining in which conditions they are the most efficient. The first experiment evaluates the variability of the output depth map data. The second experiment focuses on analyzing the influence of the distance in the positioning accuracy of an object submitted to controlled displacements. The results are summarized in a set of error heat maps and a table; they provide clues for using one sensor rather than another by describing their robustness both in a static scene and in a motion capture scenario.

关键词： Sensors Cameras Computational modeling Three-dimensional displays iterative closest point algorithm Standards Education

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Intracranial Pressure Sensor and Valve to Control Hydrocephalus

Intracranial Pressure Sensor and Valve to Control Hydrocepha...

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Annual International Conference of the IEEE Engineering in Medicine and Biology Society

作者： John G. Webster Bermans Iskandar Joshua Medow Christopher Luzzio Xuan Zhang Chenxiao Guan Zhe Yang University of Wisconsin System Madison WI US

Hydrocephalus is a neurological condition that can result from trauma, hemorrhage, cancer, and infection. To control the intracranial pressure (ICP) a shunt is implanted to drain the cerebro-spinal fluid (CSF). We are working to develop an implantable pressure sensor. When the ICP is too high it will open a valve to relieve the ICP. When the ICP is too low, it will close the valve.

关键词： Valves iterative closest point algorithm Prototypes Surgery Driver circuits Actuators Catheters

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Reducing Deformation - Augmented Reality (AR) in Facelift Surgery: A Theoretical and Mathematical Study

Reducing Deformation - Augmented Reality (AR) in Facelift Su...

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International Conference on Computer and Communication Engineering, ICCCE

作者： Shelsa Ng Abeer Alsadoon P.W.C. Prasad An Deva Paul Manoranjanl Amr Elchouemi Siong-Hoe Lau School of Computing and Mathematics Charles Sturt University Sydney Australia Faculty ofMedicine and Health Sciences Macquarie University Australia Waldern University USA Multimedia University Malaysia

Augmented Reality (AR) is increasingly used in the medical field to provide surgeons with pre-surgery visuals during surgery. To date, it has not been successful for facelift surgery which involves manipulation of facial soft tissues. This paper aims to provide an overview of current AR research for this type of procedure. Experiences with AR in related medical fields (i.e. oral and maxillofacial) have highlighted limitation arising from the elastic nature of facial soft tissues, which shift shape during surgery caused by patient and surgeon movement. This paper aims to increase overlay accuracy by reducing the elastic deformation error for AR during facelift surgery. The proposed system consists of a Gaussian Distribution and Tukey Weight (GDaTW) algorithm after the geometricerror algorithm has been applied. The proposed solution has been theoretically and mathematically justified, and a comparison table has been provided. Using AR to provide an accurate display of soft tissues in the mandibular aims to overcome occlusion by the patient's skin.

关键词： Surgery Strain Shape Biological tissues Three-dimensional displays iterative closest point algorithm Mathematical model

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Ar RIE to improve the source/drain contact in GaN HEMT

Ar RIE to improve the source/drain contact in GaN HEMT

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International Conference on Solid-State and Integrated Circuit Technology

作者： K.M. Zhu J.N. Deng X.Y. Cao J. Wan State key lab of ASIC and System School of Information Science and Engineering Fudan University China

In this work, we introduce an effective yet low cost method to improve the Ohmic contact in the AlGaN/GaN HEMT. Even with high temperature annealing, the source/drain contact shows Schottky behavior with a large turn-on voltage (V ON ) which limits the ON current of the transistor, especially under low operation voltage. An extra Ar reactive ion etching (RIE) performed after the O 2 RIE is found to largely improve the source/drain contact. The Schottky contact with high V ON is converted to Ohmic contact with negligible V ON under a moderate Ar RIE power. The relation between the Ar RIE power and V ON is studied systematically revealing an interesting trend. This effect is due to the recess of the AlGaN layer by the Ar RIE, similar to that etched by the Cl-based inductive coupled plasma (ICP). Compared to Cl-based ICP, Ar RIE has lower production cost, better environmental compatibility and is less hazardous to human health.

关键词： Aluminum gallium nitride Wide band gap semiconductors HEMTs Annealing Ohmic contacts Gallium nitride iterative closest point algorithm

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