检索结果-内蒙古大学图书馆

Color liquid crystal grating based color holographic 3D display system with large viewing angle

Light(Science & Applications) 2024年第1期13卷 103-112页

作者： Di Wang Yi-Long Li Fan Chu Nan-Nan Li Zhao-Song Li Sin-Doo Lee Zhong-Quan Nie Chao Liu Qiong-Hua Wang School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China Display Technology Research Center Seoul National UniversityGwanak-ro 1Gwanak-guSeoul 08826Republic of Korea Key Lab of Advanced Transducers and Intelligent Control System Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

Holographic 3D display is highly desirable for numerous applications ranging from medical treatments to military ***,it is challenging to simultaneously achieve large viewing angle and high-fidelity color reconstruction due to the intractable constraints of existing ***,we conceptually propose and experimentally demonstrate a simple and feasible pathway of using a well-designed color liquid crystal grating to overcome the inevitable chromatic aberration and enlarge the holographic viewing angle,thus enabling large-viewing-angle and color holographic 3D *** use of color liquid crystal grating allows performing secondary diffraction modulation on red,green and blue reproduced images simultaneously and extending the viewing angle in the holographic 3D display *** principle,a chromatic aberration-free hologram generation mechanism in combination with the color liquid crystal grating is proposed to pave the way for on such a superior holographic 3D *** proposed system shows a color viewing angle of~50.12°,which is about 7 times that of the traditional system with a single spatial light *** work presents a paradigm for achieving desirable holographic 3D display,and is expected to provide a new way for the wide application of holographic display.

关键词： holographic angle crystal

来源：评论

学校读者我要写书评

暂无评论

The kinetic characteristics of the clamping unit in injection molding machine driven by new pump control system

引用

Advances in Information Sciences and Service Sciences 2012年第21期4卷 468-475页

作者： Zhang, Hongjuan Quan, Long Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan 030024 Shanxi Province China

In the injection molding machine control system, as the toggle clamping unit has the feature of big rigidity and strong overload, it has been widely used. However the equivalent mass of the clamping unit varies in a very wide range and the intensive instantaneous impact force emerges during the mold closing and opening process, which will cause dynamic performance and control accuracy to difficultly meet the system requirements. In light of this, at first the clamping unit driven by new pump control system is designed. The characteristic and mathematic analysis is done by three-dimensional kinetics modeling and simulating. Then the control strategy of dynamic feed forward compensation and integral separation PID with anti-saturation is put forward to achieve the displacement and velocity synchronization control of the clamping cylinder. The research results are verified by co-simulation. The dynamic performance and control accuracy are improved by adopting the new pump control circuit and the control method.

关键词： Injection molding

来源：评论

学校读者我要写书评

暂无评论

controllable helical collapse caused by a nonlinearity-related Gouy phase shift

引用

Physical Review A 2024年第2期110卷 023529页

作者： Dan Wang Xin Zhang Rui-Wei Li Fan Feng Lin Lu Hui Feng Biao Feng Shao-Ding Liu Zhong-Quan Nie Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province College of Electronic Information and Optical Engineering College of Physics College of Electrical and Power Engineering College of Advanced Interdisciplinary Studies

Helical filamentation of optical fields has gained significant attention due to its potential physical properties, complexity, and practicality. However, conventional methods of manipulating filament formation face a major challenge in achieving controllable helical filamentation. We propose a method to manipulate helical collapse based on a nonlinearity-related Gouy phase shift. This method is triggered by the nonlinear interaction between vector vortex beams and anisotropic Kerr media. It is uncovered that, in the absence of the vortex, the radially polarized beam can only form the multifilament at specific locations in a BaF2 crystal. Nevertheless, once the vortex is attached, the beam can rotate based on the multifilament. The direction and angle of the rotation can be controlled by varying the topological charge number of the vortex phase. In addition, spin-orbit coupling and a rotational nonlinear refractive phase shift are generated during the helical collapse process. Finally, the physical mechanism behind this helical collapse is illustrated by a nonlinearity-related Gouy phase shift. This research presents a different approach to controlling optical field collapse and filamentation, with potential applications in various fields, including optical communications, optical manipulation, and optical microprocessing.

关键词： Light-matter interaction Nonlinear optics Self-focusing Third order nonlinear optical processes Femtosecond laser irradiation Kerr effect

来源：评论

学校读者我要写书评

暂无评论

Dynamic modelling and small signal analysis of push-pull bidirectional DC-DC converter

引用

Computer Modelling and New Technologies 2014年第10期18卷 14-18页

作者： Zhang, Hongjuan Quan, Long Gao, Yan Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan China

Bidirectional DC-DC converter can not only act as a contact bridge between two different voltage levels systems, but also can achieve the energy flow in both directions. However, due to the operating characteristics of the active switch and diode in the converter, thereby the inverter becomes a strong nonlinear circuit. In light of this, the push-pull bidirectional DC-DC converter is designed and the method of state space small signal analysis is proposed. First of all, the state-space equations of the converter are established. Then each variable of inverter circuit is averaged in a switching cycle to eliminate the influence of the switching ripple. The respective average variable expressions are decomposed into the DC component and AC small signal component. After the DC component of the signal is eliminated, the expression of the AC small signal component is obtained, to achieve the purpose of separating the small signal. Finally, the expression of small signal component is linearized, thereby the nonlinear system is approximated the DC operating point. This study will provide the theoretical foundation ready for the analysis and design of converter controller.

关键词： Linearization

来源：评论

学校读者我要写书评

暂无评论

Transient Flow Field Characteristic Analysis of Poppet Valve Based on Dynamic Mesh 6DOF Technique

Transient Flow Field Characteristic Analysis of Poppet Valve...

引用

2015 International Conference on Fluid Power and Mechatronics

作者： Guo Xiao-xia Huang Jia-hai Quan Long Wang Sheng-guo Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of Technology

In the fluid engineering, many projects involve movement and deformation of the boundary, but it is difficult to describe them by a simple algebraic expression because the movement of the boundary is determined by the force of hydraulic pressure, torque and other force which work together on the boundary. However, the previous numerical analyses are limited to the steady method or directly giving a speed to the spool which is difficult to actually simulate the movement of the spool. This paper developed a 6DOF model of a threedimensional poppet valve to stimulate the transient flow field in the opening process by means of computational fluid dynamics software—Fluent. The movement of the spool is decided by fluid force which exert on it and its gravity. By comparing numerical simulation results of the valve displacement, pressure of the control chamber and the inlet and outlet flow rate of poppet valve with the experimental results, the numerical results are the same as the experimental results. So the method that the paper proposed is feasible and more truly to simulate the flow state in the opening process of hydraulic valve. And on this basis, the pressure field, velocity field and flow regime are researched when poppet valve reaches steady state, which provides an important theoretical basis for further research on hydraulic valve performance.

关键词： poppet valve numerical calculation Dynamic Mesh Fluent

来源：评论

学校读者我要写书评

暂无评论

Research on the performance of hydraulic excavator with pump and valve combined separate meter in and meter out circuits

Research on the performance of hydraulic excavator with pump...

引用

International Conference on Fluid Power and Mechatronics (FPM)

作者： Lei Ge Zhixin Dong Weinan Huang Long Quan Jing Yang Wenyong Li Taiyuan University of Technology Key Lab of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan China

ISBN: (纸本)9781479987719

Conventional hydraulic actuator is controlled by mechanically connected orifices valve. The controllability of this method is poor and the energy consumption is huge especially under the over-running condition. So a novel system configuration of the hydraulic excavator is presented to improve the problem mentioned above, in which boom cylinder, stick cylinder and swing motor are controlled with separate meter in and meter out technology, bucket cylinder and travel motors are controlled with conventional valves. Firstly, the paper provides a comprehensive review on the development of the separate meter in and meter out technology. Then the principles of load sensing system and SMISMO system applied on the excavator are illustrated though two diagram to show the difference of the two systems. And then a virtual prototype based on the real physical structures is established, which consists of the hydraulic excavator mechanical structure with multi-body dynamics and electro-hydraulic system. The model is verified by the statics and dynamics experiments. Then the dynamic, static performances as well as the energy consumption characteristics of the boom, arm and swing actuators are investigated under the condition of load sensing hydraulic system and the proposed system using the virtual prototype. The control strategy of the actuators is formulated according to their load condition and operation characteristics also based on the detailed analysis. After that, the physical prototype based on the proposed configuration system is established and its performance is tested. The experimental results show that the accuracy of the virtual prototype is validated; the proposed configuration system can significantly decreases the pressure losses through the valve and improve the energy efficiency of the machine; the pressure shocks within hydraulic actuators is decreased as well, thus the stationarity of the whole machine is improved accordingly.

关键词： Valves Actuators Prototypes Energy consumption Cavity resonators Load modeling

来源：评论

学校读者我要写书评

暂无评论

Characteristics of a Piloted Digital Flow Valve Based on Flow Amplifier

Characteristics of a Piloted Digital Flow Valve Based on Flo...

引用

2015 International Conference on Fluid Power and Mechatronics

作者： Taotao Li Jiahai Huang Yanhong Bai Long Quan Shengguo Wang Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi ProvinceTaiyuan University of Technology

Hydraulic switching techniques which have less throttling losses, good repeatability and can be controlled intelligently have been largely developed. The biggest challenge is the hydraulic fluctuation. It is generated in the process of opening and closing the valve. A two-stage digital flow valve operated by Pulse Width Modulation(PWM) signal is studied in this paper. The main stage is cartridge valve based on flow amplifying principle;the pilot stage is high-speed on/off valve. The fluctuation characteristic of the digital flow valve is investigated using theoretical derivation and simulation analysis. The results show that the outlet flow fluctuation is influenced by many parameters such as the frequency and duty ratio of PWM signal, the volume of control chamber, etc. It can be weakened through the proper design of these parameters. Although the fluctuation exists, the mean outlet flow can be proportionally controlled by adjustment of the duty ratio of the control signal.

关键词： Flow valve,High-speed on/off valve,PWM,cartridge valve

来源：评论

学校读者我要写书评

暂无评论

The power supply design software model for mine based on VBA technology

引用

Computer Modelling and New Technologies 2014年第8期18卷 127-130页

作者： Jin, Baoquan Hao, Xiaohui Zhang, Hongjuan Gao, Yan Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Taiyuan China

Coal mine power supply system is increasingly complex, resulting in difficulties for power computing and tuning. A software design program is proposed by using VBA development tools embedded in AutoCAD secondary development, adopt object-oriented program, ActiveX automation technology and visual programming techniques to achieve human-computer interface and database interaction, design one of the mine power supply design software with function mapping, statistical calculations, protection setting, design reports automatically output, data maintenance. The study shows that the software can greatly simplify the power supply design process, improve efficiency, and can effectively improve the coal mine management level.

关键词： Software design

来源：评论

学校读者我要写书评

暂无评论

Research on Lightweight Small Object Detection Method with Fusion Attention Mechanism

Research on Lightweight Small Object Detection Method with F...

引用

2023 China Automation Congress, CAC 2023

作者： Dai, Haowen Liu, Bingyou Wan, Guoyang Qi, Jingjing Wan, Luanfei School of Electrical Engineering Anhui Polytechnic University Wuhu China Anhui Polytechnic University The Key Lab. of Advanced Perception and Intelligent Control of High-End Equipment Ministry of Education Wuhu China Anhui Dar Intelligent Control System Co. Ltd. Wuhu China Wuhu Institute of Technology Wuhu China

ISBN: (纸本)9798350303759

In the task of small object detection, due to the relatively small size of the objects, complex situations such as occlusion and overlap may arise in high-density scenes. These factors can significantly increase the issues of missed detections and false detections in object detection tasks. To address the aforementioned issues, this paper proposes a lightweight small object detection model, YOLOv5s-MGC. Firstly, we introduce an improved Mobilenetv3 network to replace the backbone network of YOLOv5s, aiming to improve the network's capability for effective feature extraction. Secondly, we incorporate the GSConv module into the feature fusion network to reduce model parameters and strengthen the network's ability in fusing feature information. Finally, we have integrated Convolutional Block Attention Module (CBAM) at the forefront of the detection heads, achieving the fusion of fine-grained features. We assessed our approach on the openly accessible dataset 'SHWD' and contrasted the results with the baseline YOLOv5s and various SOTA object detection models. Precisely, our method attains an accuracy of 91.1%, exceeding the baseline module by 1.6%. Furthermore, the module size is reduced to 1.97MB and it achieves a 52.4 FPS. In comparison to other prevailing algorithms, YOLOv5s-MGC enables efficient and accurate small object detection. © 2023 IEEE.

关键词： Object detection

来源：评论

学校读者我要写书评

暂无评论

Grain size control in quasi-two-dimensional perovskite thin film via intermediate phase engineering for efficient bound exciton generation

引用

Science China Materials 2024年第12期67卷 3925-3931页

作者： Guohui Li Wenhui Zhao Kai Lin Kefan Zhao Yujing Wang Aohua Niu Rong Weng Kaibo Zheng Yanxia Cui College of Electronic Information and Optical Engineering Key Laboratory of Interface Science and Engineering in Advanced MaterialsKey Lab of Advanced Transducers and Intelligent Control System of Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China Chemical Physics Division and NanoLund Lund UniversityBox 12422100LundSweden

Quasi-two dimensional(2D)perovskites have emerged as a promising class of materials due to their remarkable photoluminescence efficiency,which stems from their exceptionally high exciton binding *** spatial confinement of excitons within smaller grain sizes could enhance the formation of biexcitons leading to higher radiative recombination ***,the synthesis of high-quality quasi-2D perovskite thin films with controllable grain sizes remains a challenging *** this study,we present a facile method for achieving quasi-2D perovskite thin films with controllable grain sizes ranging from 500 to 900 *** is accomplished by intermediate phase engineering during the film fabrication *** results demonstrate that quasi-2D perovskite films with smaller grain sizes exhibit more efficient bound exciton generation and a reduced stimulated emission threshold down to 15.89µJ cm^(−2).Furthermore,femtosecond transient absorption measurements reveal that the decay time of bound excitons is shorter in quasi-2D perovskites with smaller grain sizes compared to that of those with larger grains at the same pump density,which is 230.5 *** observation suggests a more efficient exciton recombination process in the smaller grain size *** findings would offer a promising approach for the development of efficient bound exciton lasers.

关键词： quasi-2D perovskite intermediate phase engineering bound exciton generation grain size control

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：