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Journal of Energy Chemistry 2019年第6期28卷 167-168页

作者： Long Kong qiang Zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering Tsinghua University

The next-generation batteries with very high energy/power densities, affordable cost, safe operation are of paramount importance to electric vehicles and grid-scale storage. Lithium (Li) metal anode paired with conversion reaction cathodes (sulfur and oxygen) is regarded as a Holy Grail research because such battery system can employ earth-abundant elements and afford 3?5 times higher energy density than current lithium ion batteries (3500 Wh kg^-1 for lithium-oxygen batteries and 2600 Wh kg^-1 for lithium-sulfur batteries)[1].

关键词： Lithium metal anode Carbon nanofibers Nitrogen doped carbon nanomaterials Dendrite formation Electrochemical energy storage

Non-fullerene small molecule electron acceptors for high-performance organic solar cells

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Journal of Energy Chemistry 2018年第4期27卷 990-1016页

作者： Hao Lin qiang Wang Key Laboratory of Applied Surface and Colloid Chemistry National Ministry of Education Shaanxi Key Laboratory for Advanced Energy Devices Shaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and Engineering Shaanxi Normal University

Fullerenes and their derivatives are important types of electron acceptor materials and play a vital role in organic solar cell devices. However, the fullerene acceptor material has some difficulties to overcome the intrinsic shortcomings, such as weak absorption in the visible range, difficulty in modification and high cost, which limit the performance of the device and the large-scale application of this type of acceptors. In recent years, non-fullerene electron acceptor material has attracted the attention of scientists due to the advantages of adjustable energy level, wide absorption, simple synthesis, low processing cost and good solubility. Researchers can use the rich chemical means to design and synthesize organic small molecules and their oligomers with specific aggregation morphology and excellent optoelectronic prop- erties. Great advances in the field of synthesis, device engineering, and device physics of non-fullerene acceptors have been achieved in the last few years. At present, non-fullerene small molecules based photovoltaic devices achieve the highest efficiency more than 13% and the efficiency gap between fullerenetype and non-fullerene-type photovoltaic devices is gradually narrowing. In this review, we explore recent progress of non-fullerene small molecule electron acceptors that have been developed and led to highefficiency photovoltaic devices and put forward the prospect of development in the future.

关键词： Organic solar cells Non-fullerene Electron acceptors Bulk heterojunction

Co-metric： a metric learning algorithm for data with multiple views

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Frontiers of Computer Science 2013年第3期7卷 359-369页

作者： qiang QIAN Songcan CHEN Department of Computer Science and Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China

We address the problem of metric learning for multi-view data. Many metric learning algorithms have been proposed, most of them focus just on single view circumstances, and only a few deal with multi-view data. In this paper, motivated by the co-training framework, we propose an algorithm-independent framework, named co-metric, to learn Mahalanobis metrics in multi-view settings. In its implementation, an off-the-shelf single-view metric learning algorithm is used to learn metrics in individual views of a few labeled examples. Then the most confidently-labeled examples chosen from the unlabeled set are used to guide the metric learning in the next loop. This procedure is repeated until some stop criteria are met. The framework can accommodate most existing metric learning algorithms whether types-of- side-information or example-labels are used. In addition it can naturally deal with semi-supervised circumstances under more than two views. Our comparative experiments demon- strate its competiveness and effectiveness.

关键词： multi-view learning metric learning algorithm- independent framework

Exact solution for capillary interactions between two particles with fixed liquid volume

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Applied Mathematics and Mechanics(English Edition) 2016年第12期37卷 1597-1606页

作者： Fengxi ZHOU qiang MA School of Civil Engineering Lanzhou University of Technology

The capillary interactions, including the capillary force and capillary suction, between two unequal-sized particles with a fixed liquid volume are investigated. The cap- illary interaction model is used within the Young-Laplace framework. With the profile of the meridian of the liquid bridge, the capillary suction, and the liquid volume as state variables, the governing equations with two-fixed-point boundary axe first derived using a variable substitution technique, in which the gravity effects are neglected. The capillary suction and geometry of the liquid bridge with a fixed volume are solved with a shooting method. In modeling the capillary force, the Gorge method is applied. The effects of var- ious parameters including the distance between two particles, the ratio of particle radii, and the liquid-solid contact angles are discussed.

关键词： liquid bridge Young-Laplace equation fixed liquid volume shootingmethod

Optimal feedback gains of a delayed proportional-derivative(PD) control for balancing an inverted pendulum

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Acta Mechanica Sinica 2017年第3期33卷 635-645页

作者： qiang Wang Zaihua Wang Institute of Science PLA University of Science and Technology State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

In the dynamics analysis and synthesis of a controlled system, it is important to know for what feedback gains can the controlled system decay to the demanded steady state as fast as possible. This article presents a systematic method for finding the optimal feedback gains by taking the stability of an inverted pendulum system with a delayed proportional-derivative controller as an example. First, the condition for the existence and uniqueness of the stable region in the gain plane is obtained by using the D-subdivision method and the method of stability switch. Then the same procedure is used repeatedly to shrink the stable region by decreasing the real part of the rightmost characteristic root. Finally, the optimal feedback gains within the stable region that minimizes the real part of the rightmost root are expressed by an explicit formula. With the optimal feedback gains, the controlled inverted pendulum decays to its trivial equilibrium at the fastest speed when the initial values around the origin are fixed. The main results are checked by numerical simulation.

关键词： Inverted pendulum Time delay Stability Rightmost characteristic root Optimal feedback gain

Precision Design for Machine Tool Based on Error Prediction

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Chinese Journal of Mechanical Engineering 2013年第1期26卷 151-157页

作者： HUANG qiang ZHANG Genbao College of Automobile Chongqing University of Technology College of Mechanical Engineering Chongqing University

Digitization precision analysis is an important tool to ensure the design precision of machine tool currently. The correlative research about precision modeling and analysis mainly focuses on the geometry precision and motion precision of machine tool, and the forming motion precision of workpiece surface. For the machine tool with complex forming motion, there is not accurate corresponding relationship between the existing criterion on precision design and the machining precision of workpiece. Therefore, a design scheme on machine tool precision based on error prediction is proposed, which is divided into two-stage digitization precision analysis crucially. The first stage aims at the technology system to complete the precision distribution and inspection from the workpiece to various component parts of technology system and achieve the total output precision of machine tool under the specified machining precision; the second stage aims at the machine tool system to complete the precision distribution and inspection from the output precision of machine tool to the machine tool components. This article serves YK3610 gear hobber as the example to describe the error model of two systems and basic application method, and the practical cutting precision of this machine tool achieves to 5-4-4 grade. The proposed method can provide reliable guidance to the precision design of machine tool with complex forming motion.

关键词： complex forming motion machine tool precision design position-pose error error sensibility

On Cost Aware Cloudlet Placement for Mobile Edge Computing

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IEEE/CAA Journal of Automatica Sinica 2019年第4期6卷 926-937页

作者： qiang Fan Nirwan Ansari IEEE Advanced Networking Lab Department of Electrical and Computer EngineeringNew Jersey Institute of TechnologyNewarkUSA

As accessing computing resources from the remote cloud inherently incurs high end-to-end(E2E)delay for mobile users,cloudlets,which are deployed at the edge of a network,can potentially mitigate this *** some research works focus on allocating workloads among cloudlets,the cloudlet placement aiming to minimize the deployment cost(i.e.,consisting of both the cloudlet cost and average E2E delay cost)has not been addressed effectively so *** locations and number of cloudlets have a crucial impact on both the cloudlet cost in the network and average E2E delay of ***,in this paper,we propose the Cost Aware cloudlet PlAcement in moBiLe Edge computing(CAPABLE)strategy,where both the cloudlet cost and average E2E delay are considered in the cloudlet *** solve this problem,a Lagrangian heuristic algorithm is developed to achieve the suboptimal *** cloudlets are placed in the network,we also design a workload allocation scheme to minimize the E2E delay between users and their cloudlets by considering the user *** performance of CAPABLE has been validated by extensive simulations.

关键词： Cloudlet placement mobile cloud computing mobile edge computing

Four-Particle Entangled State Representation and Its Squeezing Transformation

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Communications in Theoretical Physics 2005年第6期43卷 1107-1110页

作者： SONGTong-qiang DepartmentofPhysics NingboUniversityNingbo315211China

The four-particle EPR entangled state is constructed. Thecorresponding quantum mechanical operator with respect to the classical transformation p → e~(λ1)p, X2 → e~(λ2)X2, X3 → e~(λ3) X3, and X4 → ee~(λ4) X4 in the state isinvestigated, and the four-mode realization of the S U(1, 1) Lie algebra as well as thecorresponding squeezing operators are presented.

关键词： four-mode entangled state representation squeezing transformation four-modesqueezing operator

Effects of Ti_(0.5)Al_(0.5)N coatings on the protecting against oxidation for titanium alloys

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Rare Metals 2010年第2期29卷 154-161页

作者： RU qiang HU Shejun Laboratory of Quantum Information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China Department of Mathematics and Physics Wuyi University Jiangmen 529020 China

Ti0.5Al0.5N coatings were deposited on TC11（Ti-6.5Al-3.5Mo-1.5Zr-0.3Si） and silicon substrates using a cathode arc ion-plating *** microstructure, composition, phase structure, and oxidation-resistance of the alloys and nitride coatings were investigated by scanning electron microscopy, X-ray diffraction, transmission electron microscopy, Auger electron spectroscopy, and thermal *** results show that the oxidation resistance of the titanium alloy is relatively limited;the compound structures of Ti mixed with Al oxides are formed during the heating *** phases of the Ti0.5Al0.5N coatings are composed of a TiN solid solution *** oxidation kinetics obeys the parabolic *** the oxidation process, the selective oxidation of Al occurs, thus protecting the underlying coating and substrate.

关键词： titanium alloy TiAlN oxidation resistance ion plating

Nonlinear Einstein-Podolsky-Rosen Entangled States

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Communications in Theoretical Physics 2004年第2X期42卷 271-274页

作者： SONGTong-qiang DepartmentofPhysics NingboUniversityNingbo315211China

Using the properties of the inverses of annihilation and creation operators of f-oscillator we introduce the notion of nonlinear Einstein Podolsky-Rosen entangled state and study its properties.

关键词：非线性EPR纠缠态广义双模魏格纳算子非线性量子态量子器件傅立叶变换