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| 1 | Wireless Communications with Programmable Metasurface:Transceiver Design and Experimental Results显示文摘Metasurfaces have drawn significant attentions due to their superior capability in tailoring electromagnetic waves with a wide frequency range, from microwave to visible light. Recently, programmable metasurfaces have demonstrated the ability of manipulating the amplitude or phase of electromagnetic waves in a programmable manner in real time, which renders them especially appealing in the applications of wireless communications. In this paper, we present the fundamental principle of applying programmable metasurface as transmitter for wireless communications. Then, we establish a prototype system of metasurface-based transmitter to conduct several experiments and measurements over the air, which practically demonstrate the feasibility of using programmable metasurfaces in future communication systems. By exploiting the dynamically controllable property of programmable metasurface, the design, implementation and experimental evaluation of the proposed metasurface-based wireless communication system are presented with the prototype, which realizes single carrier quadrature phase shift keying(QPSK) transmission over the air. In the developed prototype, the phase of the reflected electromagnetic wave of programma-ble metasurface is directly manipulated in real time according to the baseband control signal, which achieves 2.048 Mbps data transfer rate with video streaming transmission over the air. In addition, experimental result is provided to compare the performance of the proposed metasurface-based architecture against the conventional one. With the slight increase of the transmit power by 5 dB, the same bit error rate(BER) performance can be achieved as the conventional system in the absence of channel coding. Such a result is encouraging considering that the metasurface-based system has the advantages of low hardware cost and simple structure, thus leading to a promising new architecture for wireless communications. | Wankai Tang Xiang Li Jun Yan Dai Shi Jin Yong Zeng Qiang Cheng Tie Jun Cui | 2019 | China Communications2019，16，5： | 23 |
| 2 | An Integrated Decision Support System for Macroscopic Coordinative Development | LIU Shaojun HAN Chongzhao and WAN BaiwuInstitute of Systems Engineering, Xi’an Jiaotong UniversityXi’an 710049, P.R.China | 1993 | Systems Science and Systems Engineering1993，3，4： | 3 |
| 3 | A Knowledge-based System for the Analysis of the Ability of Paying back Loans显示文摘This paper describes the development of a knowledgebased system (KBS) for determining whether or not, and under what conditions, a bank Ioan officer should grant a business loan to a company. The prototype system developed focuses on what is bank loans risks management, how to prevent risk by the analysis of the ability of paying back loans. The paper makes the structural analysis involved in the system's decision situation, the structured situation diagram or model, dependency diagram and the document needed by the KBS prototype system thus are developed. Through testing the samples from loan business, the quality for the analysis of the ability of paying back loans can be effectively evaluated by the KBS prototype system. | Zhu Ming(朱明) Yang Baoan(杨保安) | 2001 | Journal of Donghua University(English Edition)2001，18，1： | 1 |
| 4 | Research on Nonlinear Dynamic Simulation and Fatigue Reliability Life Prediction for Synthesis Transmission System of Self-Propelled Gun显示文摘Aiming to the puzzle that the inner load of nonlinear synthesis transmission system is difficult to obtain,a new kind of virtual prototype establishment and simulation method is put forward. The influence on nonlinear vibration with flexible rotor, bearing backlash is analyzed based on a virtual prototype. To validate the virtual prototype of nonlinear gear transmission system, the corresponding test platform is established. The consistency between simulation results and test results proves that the simulation results of the virtual prototype can be used to calculate the fatigue reliability life of key components. A new kind of fatigue reliability life prediction method of gear system considering multi-random parameter distribution is put forward based on the fatiguestatistic theory. Considering the periodicity of gear meshing, linear interpolation method is adopted to obtain the stress-time course of random load spectrum based on the gear's complicated torque provided by virtual prototype.The gear's P-Sa-Sm-N curved cluster can be simulated based on material's P-S-N curve. The simulation process considers the parameter distributions of stress concentration coefficients, dimension coefficients and surface quality treatment coefficients, and settles the puzzle that traditional test methods cannot acquire the gear's fatigue life of all reliability levels. This method can provide the distribution function and the interval of fatigue reliability life of gear's danger region, and has a guide meaning for the gear maintenance periods determination and reliability evaluation. | 于贵波 曹立军 王书海 马乔 | 2018 | Journal of Shanghai Jiaotong university(Science)2018，23，6： | 1 |
| 5 | 3-D Design and Numerical Simulation of Two-Phase Flow in the Laser Rapid Prototyping Coaxial Powder Delivery System显示文摘The metal powder direct and rapid prototyping technology is one of the most developing methods in the laser rapid prototyping technique. The coaxial powder delivery system is the key technique. The purpose of this paper is to introduce a new type of coaxial powder delivery system and simulate the metal powder and shield gas flow in the powder nozzle. 2-D and 3-D model of the new coaxial powder delivery system are established. Then gas-solid two-phase flow model and the k-ε turbulent model are selected to simulate the flow of metal powder in powder nozzle. The Euler-Lagrange method is used in the simulating computation. The results show that the new coaxial powder delivery system has stable performance, uniform powder flux, high cooling efficiency, and long useful life. | 王志坚 仉安娜 尚晓峰 | 2009 | Tsinghua Science and Technology2009，14，S1： | 0 |
| 6 | Mechanical and Experimental Study of Sprinkling Water Cooling System on Roof of Shanghai Expo Theme Pavilion显示文摘Based on the similarity theory,a scale effect model of the spraying water cooling system of Shanghai expo Theme Pavilion's roof was set up.According to the typical weather conditions in Shanghai city,different models were analyzed on solar radiation,and different heat transfer amount was obtained.And the following conclusions could be made:At the sunny day of summer in Shanghai,the temperature of inner roof with sprinkling system descended about 3 ℃,and the air conditioning load of the whole Theme Pavilion descend more than 320 kW. | ZHAO Hui-zhong1,HUANG Chen1,LI Wei-xiang2,SHI Jin-yue2,TAO Si-yuan1,WANG Qian1,WANG Yu-qing1,ZHANG Min3(1.College of Urban Construction and Environment Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China 2.Architectural Design & Research Institute of Tongji University,Shanghai 200092,China 3.College of Food Science Technology,Shanghai Ocean University,Shanghai 201306,China) | 2009 | 湖南大学学报(自然科学版)2009，36，S1： | 0 |
| 7 | OOCAP——A KNOWLEDGE BASED OBJECT-ORIENTED CAPP PROTOTYPE SYSTEM显示文摘The prototype system Object-Oriented Computer Aided Process Planning(OOCAP),which aims at simulating machine process planning for designed componentsby constructing a knowledge based system in an Object-Oriented environment Smalltalkand is implemented in PS/2 80,is presented in this paper.The integration of rules,factsand operations in objects is the key concept in the system.Additionally,the system simu-lares machining processes and shows the whole procedure from selecting materials to get-ring products with animations. | 王茜 | 1992 | Journal of Southeast University(English Edition)1992，8，1： | 0 |
| 8 | Building Urban Land Information Management System in PostgreSQL,for the Case of Ethiopia显示文摘Population growth and rapid urbanization have caused an exponential increase in urban land demand in Ethiopia.The information required for land administration and management has been tremendously increasing as well.Therefore,this paper describes the steps for a building database prototype for urban land information management system for the case of Ethiopia which results to develop an efficient and effective way of spatial and non-spatial urban land data management system.This research project will develop a central database system using a PostgreSQL software to retrieve,update and store the required data using a user-friendly graphical interface.System requirement and specification is devoted to a system design which incorporates the intended system behaviour using a use case diagram,logical design of the system using a class diagram.The design system is validated and tested via sample data which can store,retrieve,and update the required data as per the user requirement.Developing this type of urban land information management system,therefore,facilitates and increases the efficiency of land registration and related activities at the municipality level.Thence,citizens would be satisfied by the service delivery of the municipality.The land and real estate ownerships registration will also become automated.Furthermore,any spatial and non-spatial data related with the system can be stored in the database which will be ready for more analysis as to be able to use by policymakers,urban planners for the purpose of sustainable development of urban area infrastructural developments and land use policy.The research will lay ground for another task to develop CityGML 3D modelling for selected cities thereby contributes to spatial data infrastructure development to Ethiopia. | Abraham Kelilo Tula Firaol Befikadu Geleta | 2019 | 通讯和计算机(中英文版)2019，15，1： | 0 |
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