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Layered multicast congestion control by particle swarm optimization in heterogeneous environment

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The Journal of China Universities of Posts and Telecommunications 2011年第3期18卷 85-91页

作者： MA Hai-yuan MENG Xiang-ru MA zhi-qiang LI Jin-liang The Telecommunication Engineering Institute Air Force Engineering University Xi'an 710077 China

To enhance multicast throughput in heterogeneous environment, a new layered multicast congestion control scheme is proposed. With the goal of maximizing global satisfaction of the whole group, allocating sending rate in each layer is formulated to an optimization problem. Since the problem is noncovexity, the sender uses particle swarm optimization to search a set of optimal layers rates. The new scheme also eliminates ＇lowest-first＇ phenomenon by proposing a feedbacks suppression algorithm named equal-probability sampling （EPS）. Upon EPS all the receivers send feedbacks at equal probability without bias. Simulation results prove that the new scheme can enhance global satisfaction and multicast throughput efficiently, compared with the traditional layered multicast congestion control scheme based on representatives.

关键词： layered multicast congestion control particle swarm optimization feedbacks suppression

New Measurement Method for Spline Shaft Rolling Performance Evaluation using Laser Displacement Sensor

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 124-132页

作者： Hong-Wei Li zhi-qiang liang Jia-Jie Pei Li Jiao Li-Jing Xie Xi-Bin Wang Key Laboratory of Fundamental Science for Advanced Machining Beijing Institute of Technology Beijing North Vehicle Group Corporation

In order to control the quality of spline shaft in rolling process, an efficient measurement method for rolling performance evaluation is essential. Here, a newly developed on-machine non-contact measurement prototype based on laser displacement sensor and rotary encoder is proposed. The prototype is intended for the automated evaluation of the spline shaft rolling performance by measuring the dimensional change of tooth root, which is correlated with the surface residual stress and micro-hardness. Laser displacement sensor and rotary encoder are used to record the polar radius and polar angle of each point on measuring section. Data are displayed in a polar coordinate system and fitted in a gear. Through multipoint curvature method, the roots of spline shaft are recognized automatically. Then, the dimensional change can be calculated by fitting the radius of the tooth root circle before and after rolling. Systematic error covering offset error is also analyzed and calibrated. At last, measurement test results show that the system has advantages of simple structure, high measurement precision(radius error < 0.6 μm), high measurement efficiency(measuring time < 2 s) and automatic control ability, providing a new opportunity for the efficient evaluation of various spline shafts in high-precision mechanical processing.

关键词： Laser measurement Spline shaft Rolling performance Dimensional change

Mechanism of brittle fracture in diamond turning of microlens array on polymethyl methacrylate

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Advances in Manufacturing 2019年第2期7卷 228-237页

作者： Tian-Feng Zhou Ben-Shuai Ruan Jia Zhou Xiao-Bin Dong zhi-qiang liang Xi-Bin Wang Key Laboratory of Fundamental Science for Advanced Machining Beijing Institute of Technology Beijing 100081 People's Republic of China School of Mechanical Engineering Beijing Institute of Technology Beijing 100081 People's Republic of China

Diamond cutting is a popular method to fabricate microlens array (MLA) on polymethyl methacrylate (PMMA);however, it is limited by brittle fracture, which is formed easily on the surface of MLA during the cutting process. In this paper, the formation mechanism of the brittle fracture is studied via a series of experiments including the slow tool servo (STS) cutting experiment of MLA, surface scratching experiment and suddenstop cutting experiment. The effects of undeformed chip thickness, feed rate, and machining track on brittle fracture formation are investigated in detail. In addition, based on the fracture formation mechanism, a bi-directional cutting approach is proposed to eliminate the regional brittle fracture of the microlens during diamond cutting. An experiment was then conducted to verify the method;the results demonstrated that bi-directional cutting could eliminate brittle fracture entirely. Finally, a spherical MLA with the form error (vPV) of 60 nm and the surface roughness (Ra) of 8 nm was successfully fabricated.

关键词： Microlens array (MLA) Polymethyl methacrylate (PMMA) Brittle fracture Bi-directional cutting

Research on dynamic response characteristics of CFRP/Al HC SPs subjected to high-velocity impact

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Defence Technology（防务技术） 2018年第5期14卷 503-512页

作者： Guo-wen Gao En-ling Tang Min-hui Feng Ya-fei Han Yue Li Mei Liu Ying-liang Xu Li Wang Xiao-chu Lin Rui-zhi Wang Yi-guang Cheng liang-liang Zhao zhi-qiang liang Jun-ru Wang Guan-jie Zhao Qing Gao Tian-zhi Zheng School of Equipment Engineering Shenyang Ligong University

CFRP/Al HC SPs(Carbon Fiber Reinforced Plastic/Aluminum Honeycomb Sandwich Panels)composite structures are widely used in the aerospace and many other fields due to their excellent performances. In order to reveal profoundly the dynamic response characteristics of CFRP/Al HC SPs composite structure under high-velocity impact loading, the experiments about aluminum honeycomb core and CFRP/Al HC SPs composite structure impacted by high-velocity projectiles have been performed by using a one-stage light gas gun loading and a high-speed camera systems, respectively. The whole physical process of collision is analyzed by using TEMA software which is provided by high-speed camera's manufacturer,and the pictures and related physical parameters of the projectile passing through the different layers at the key moments are extracted based on the set frame rate of the video. Meanwhile, the ABAQUS/Explicit module was used to conduct numerical simulation under the same conditions as the experiments, and extracting the pictures and related physical parameters during the projectile penetrating through aluminum honeycomb core and the sandwich panels at the different key moments. The results show that the durations of action for the projectile impacting the Al HC core and the CFRP/Al HC SPs at the velocity about 280 m/s were 86 μs and 240 μs in experiments, respectively, and the durations of action were 90.7μs and 236.2 μs at the same experimental conditions in numerical simulation, which were basically consistent comparing the experimental to simulated results. Moreover, more than 70% for the kinetic energy of the projectile consumed by the sandwich panels was attributed to the front panel and the aluminum honeycomb core during the entire impact process, and all these have verified the reliability of the numerical simulation.

关键词： ABAQUS/Explicit Duration of action between projectile and target Energy absorption

Grape Skin Polyphenols （GSPs） Inhibit the Migration of Mouse Mammary Carcinoma 4T1 Cells in Vitro

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Clinical oncology and cancer researeh 2011年第1期8卷 33-37页

作者： Qiu-yu CHEN zhi-qiang liang Tao SUN Xiang-jun SUN College of Agriculture and Biology Shanghai Jiaotong University Shanghai 200240 China College of Food Science and Engineering Shanxi Agricultural University Shanxi 030800China

OBJECTIVE 1） To study the efficacy of GSPs on the migration of highly metastatic mammary carcinoma cells and 2） To investigate inhibition *** Cell migration was assessed using a 24-well transwell assay. Cells with different concentrations of GSPs were suspended （5×105 cell/mL） in RPMI 1640 media in the upper chamber, and RPMI 1640 media with 10% FBS was supplemented in the lower chamber. Then, cells were allowed to migrate for 24 *** GSPs inhibited the migration of 4T1 cells in a dosedependent manner. The migration of 4T1 cells was obviously inhibited by GSPs, even at a very low concentration （5 μg/mL）,and was totally inhibited when the concentration was 20 μg/***, 20 μg/mL of GSPs inhibited cell viability by only 11.4% and induced early apoptosis by only 5.6% compared with a percentage of 4.0% in control cells. GSPs suppressed the activation of PDK1,Akt and Erk1/2 in a dose-dependent *** GSPs significantly inhibit the migration of highly metastatic mammary carcinoma 4T1 cells in vitro. This inhibition is independent of decreased cell viability or apoptosis induction. The inhibition of migration by GSPs is involved in blocking the PI3k/Akt and MAPK pathways.

关键词： grape skin polyphenols (GSPs) mammary carcinoma cells migration inhibition mechanism

Prediction Model of Soil Nutrients Loss Based on Artificial Neural Network

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Journal of Northeast Agricultural University(English Edition) 2001年第1期8卷 37-42页

作者： WANG zhi-liang,FU qiang,liang Chuan (Hydroelectric College,Sichuan University) Hydroelectric College Sichuan University

On the basis of Artificial Neural Network theory, a back propagation neural network with one middle layer is building in this paper, and its algorithms is also given, Using this BP network model, study the case of Malian-River basin. The results by calculating show that the solution based on BP algorithms are consis- tent with those based multiple - variables linear regression model. They also indicate that BP model in this paper is reasonable and BP algorithms are feasible.

关键词： soil Prediction Model of Soil Nutrients Loss Based on Artificial Neural Network

Preoperative surgical planning and simulation of complex cranial base tumors in virtual reality

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Chinese Medical Journal 2008年第12期121卷 1134-1136页

作者： YI zhi-qiang LI liang MO Da-peng ZHANG Jia-yong ZHANG Yang BAO Sheng-de Department of Neurosurgery Peking University First Hospital Beijing 100034 China

The extremely complex anatomic relationships among bone, tumor, blood vessels and cranial nervesremains a big challenge for cranial base tumor surgery. Therefore, a good understanding of the patient specific anatomy and a preoperative planning are helpful and crucial for the neurosurgeons. Three dimensional （3-D） visualization of various imaging techniques have been widely explored to enhance the comprehension of volumetric data for surgical planning.

关键词： cranial base neoplasm three dimensional image virtual reality

Anomalous vertebral artery not passing through the transverse foramen of the atlas

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Chinese Medical Journal 2009年第21期122卷 2675-2677页

作者： YI zhi-qiang LI liang MO Da-peng ZHANG Jia-yong ZHANG Yang BAO Sheng-de Department of Neurosurgery Peking University First Hospital Beijing 100034 China

Ssually the vertebral artery （VA） arises from the first part of the subclavian artery and enters the transverse foramen of the C-6 vertebra （first segment） and then ascends through the transverse foramen from C-6 to the atlas （second segment）. In its third segment, the artery emerges on the superior surface of the atlas and curves horizontally over the lateral and posterior surfaces of the superior articular process of C-1 and then passes medially in front of the posterior atlanto-occipital membrane. In its fourth segment, the artery pierces the dura mater and arachnoid between the occipital bone and atlas then enters the cranial cavity through the foramen magnum. To identify and preserve the VA is vital in the surgery of the craniaocervical and cervical region. However, the variations of the VA complicate the procedures of VA identification. It is valuable to know the course of VA preoperatively. Some anatomical variations of the VA occur due to its abnormal development process.

关键词： vertebral artery cervical atlas computed tomography angiography virtual reality

“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： Yan Zhao qiang Yuan Liting Yang Guisheng liang Yifeng Cheng Limin Wu Chunfu Lin Renchao Che College of Physics Donghua UniversityShanghai 201620People’s Republic of China School of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization