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A novel method for PAPR reduction of the OFDM signal using nonlinear scaling and FM Regular Article
Yi-hu Xu, Jung-Yeol Oh, Zhen-hao Sun, Myoung-Seob Lim,xuyh@ybu.edu.cn,mslim@jbnu.ac.kr
Frontiers of Information Technology & Electronic Engineering 2019, Volume 20, Issue 11, Pages 1587-1594 doi: 10.1631/FITEE.1800438
Keywords： 正交频分复用；峰均比；非线性缩放；调频技术
Hydraulic Pressure Extremes Ratio & Extremes Ratio Efficiencies
Qi Maolin
Strategic Study of CAE 2001, Volume 3, Issue 4, Pages 73-75
This article applies basic formula to the calculation of a relationship between the hydraulic pressure extremes ratio of hydraulic system and the extremes ratio efficiencies. This relationship shows that the greater the hydraulic pressure extremes ratio is, the lower the extremes ratio efficiencies are. The article holds that the hydraulic pressure extremes ratio can be designed and chosen.
Keywords： hydraulic pressure extremes ratio extremes ratio efficiencies hydraulic system
Controllability of Boolean control networks with multiple time delays in both states and controls Research Article
Yifeng LI, Lan WANG,liyifeng@cqnu.edu.cn,wanglan202212@126.com
Frontiers of Information Technology & Electronic Engineering 2023, Volume 24, Issue 6, Pages 906-915 doi: 10.1631/FITEE.2200618
Keywords： Boolean control networks Semi-tensor product of matrices Controllability Time delay
Scheme comparison of Qiongzhou strait railway tunnel
Tan Zhongsheng,Wang Mengshu,Luo Shixiang
Strategic Study of CAE 2009, Volume 11, Issue 7, Pages 39-44
The construction of the Qiongzhou strait tunnel will not only meet the requirements of the straits' passenger and cargo traffic,but also the needs of national defense, and the constructed tunnel will play a huge pulling role in Hainan´s economic development.Comparing with the similar projects abroad, the preliminary work of Qiongzhou strait tunnel was very urgent and needed a long time, because of enormous workload of research, complex technology and difficulties. Based on the study of meteorological, hydrological, geological data and other information of Qiongzhou strait tunnel, the bridge and tunnel schemes are simply compared, which indicate that the tunnel scheme is suitable, moreover, the shield tunnel scheme for line Ⅱ is better than others. After compared the shallow tunnel with deep tunnel schemes of line Ⅱ, the shallow tunnel using shield method scheme is proposed. As highway tunnel had many technical problems, and project costs and operating costs are very high, therefore, the railway tunnel plan as the preferred option is feasible, and cars could pass through the tunnel by shuttle trains.
Keywords： Qiongzhou strait railway tunnel programme selection
The analysis of specific energy applied in Bohai Strait tunnel during TBM construction
Gao Pan,Zou Chong
Strategic Study of CAE 2013, Volume 15, Issue 12, Pages 73-79
The proposed Bohai Strait tunnel is a challenging project, and penetration rate of tunnel boring machine (TBM) is one of the keys. This paper made a contrast between the Clem Jones tunnel in Australia and the Bohai Strait tunnel,and introduced the specific energy used in the Clem Jones tunnel. During the construction of the Clem Jones tunnel, researchers made the analysis and forecasted about the TBM's penetration rate using the specific energy, which was identical to the practical construction very well. This paper concluded that the specific energy can be used in the Bohai Strait tunnel as well as the Clem Jones tunnel,which was based on the comparative analysis of the Clem Jones tunnel and Bohai Strait tunnel.
Keywords： TBM specific energy drilling rate index penetration rate
Jaw Crusher With Large Reduction Ratio and the Modification of Crushing Technology
Rao Qilin
Strategic Study of CAE 2001, Volume 3, Issue 4, Pages 82-87
A new type crushing equipment - the outer moving jaw crusher with large reduction ratio and its technical parameters, as well as its performance characteristics are introduced. The structural nature of large reduction ratio makes it possible to substitute the two or three stage crushing in the traditional crushing flowsheet by only one stage. That is, the successful development of the new type crushing equipment will bring about the change of the crushing technology.
Keywords： cursher large reduction ratio simplification of flowsheet
Analysis of Influencing Factors on Transmission Ratio in Magnetic Metal Belt Transmission
Luo Shanming,Miao Xiexing
Strategic Study of CAE 2002, Volume 4, Issue 3, Pages 73-77
Magnetic metal belt transmission is a new one in which the initial tension no longer solely, but together with the magnetic attraction force produces the friction force. The influencing factors on transmission ratio are analyzed and numerically simulated in this paper, such as effective haulage force, initial tension, magnetic induction intensity, center distance, diameter of the smaller belt pulley and angle of contact. The change laws of transmission ratio along with these influencing factors are studied. The results show that the transmission ratio of magnetic metal belt transmission increases when magnetic induction density, initial tension and center distance increases, and decrease when angle of contact and diameter of the smaller belt pulley increases. It is pointed out that the angle of contact and diameter of the smaller belt pulley can be reduced accordingly because of the effect of magnetic force, and therefore the transmission ratio can increase by 3〜4 times compared with general belt transmission.
Keywords： belt transmission magnetism metal belt transmission ratio
The Analysis on Output-input Ratio of Artificial Supplementary Energy in Agro-eco-engineering
Bian Yousheng,Liu Yingkun,Bian Jing
Strategic Study of CAE 2006, Volume 8, Issue 8, Pages 28-32
The output-input ratio of the artificial Supplementary energy reflects the function and productivity of an agro-eco-engineering as a whole. It is one of the important indicators measuring the effects of an agro-eco-engineer. The output-input ratio for artificial supplementary energy of Henan Xinxian´10 peasant families has been calculated successively for three years.
Multiscale Homogenization Analysis of Alkali–Silica Reaction (ASR) Effect in Concrete Article
Roozbeh Rezakhani, Mohammed Alnaggar, Gianluca Cusatis
Engineering 2019, Volume 5, Issue 6, Pages 1139-1154 doi: 10.1016/j.eng.2019.02.007
The alkali–silica reaction (ASR) is one of the major long-term deterioration mechanisms occurring in concrete structures subjected to high humidity levels, such as bridges and dams. ASR is a chemical reaction between the silica existing inside the aggregate pieces and the alkali ions from the cement paste. This chemical reaction produces ASR gel, which imbibes additional water, leading to gel swelling. Damage and cracking are subsequently generated in concrete, resulting in degradation of its mechanical properties. In this study, ASR damage in concrete is considered within the lattice discrete particle model (LDPM), a mesoscale mechanical model that simulates concrete at the scale of the coarse aggregate pieces. The authors have already modeled successfully ASR within the LDPM framework and they have calibrated and validated the resulting model, entitled ASR-LDPM, against several experimental data sets. In the present work, a recently developed multiscale homogenization framework is employed to simulate the macroscale effects of ASR, while ASR-LDPM is utilized as the mesoscale model. First, the homogenized behavior of the representative volume element (RVE) of concrete simulated by ASR-LDPM is studied under both tension and compression, and the degradation of effective mechanical properties due to ASR over time is investigated. Next, the developed homogenization framework is utilized to reproduce experimental data reported on the free volumetric expansion of concrete prisms. Finally, the strength degradation of prisms in compression and four-point bending beams is evaluated by both the mesoscale model and the proposed multiscale approach in order to analyze the accuracy and computational efficiency of the latter. In all the numerical analyses, different RVE sizes with different inner particle realizations are considered in order to explore their effects on the homogenized response.
Keywords： Multiscale homogenization Representative volume element Alkali–silica reaction Lattice discrete particle model
Study on scheme comparison of bridge and tunnel for Bohai Strait cross-sea channel
Song Kezhi
Strategic Study of CAE 2013, Volume 15, Issue 12, Pages 52-60
Aspects of bridge and tunnel are analyzed and their characteristics are compared,such as aviation and shipping, traffic capacity and driving comfort, road safety and climate adaptability,construction difficulty and project risk, etc. Technically, schemes of bridge and tunnel are both workable. Tunnel scheme is privilege to bridge scheme on aviation, shipping, climate adaptability, ecological environment and so on. While bridge scheme has advantages over tunnel scheme on traffic capacity, construction difficulty and risk, operating costs, driving safety, driving comfort, landscape and so on. Comparative evaluation index system for Bohai Strait cross-sea channel is structured by analytic hierarchy process. And weight coefficients of every index are calculated. Membership grade of every qualitative index is calculated by experts scoring method and membership grade of every quantitative index is calculated by membership grade function. Finally, model of fuzzy comprehensive evaluation is used to calculate comprehensive evaluation value of full bridge scheme, full tunnel scheme and combination scheme of bridge and tunnel. Comprehensive evaluation value of full tunnel scheme is maximum and the full tunnel scheme is the recommended scheme for Bohai Strait cross-sea channel.
Keywords： bridge and tunnel engineering cross-sea channel Bohai Strait scheme comparison fuzzy comprehensive evaluation
Technological Approaches to Increasing Specific Power of Vehicular Fuel Cell Stacks
Hou Ming, Shao Zhigang, Yi Baolian
Strategic Study of CAE 2019, Volume 21, Issue 3, Pages 84-91 doi: 10.15302/J-SSCAE-2019.03.002
As a type of new energy vehicle, fuel cell vehicle has attracted increasing attention because of its long driving distance, high power performance, fast fuel filling, and compatibility with renewable energies. Fuel cell stack is the core of a fuel cell vehicle, and specific power indicates the technical level of a fuel cell stack. Using a high-specific-power fuel cell stack technology, the number of stack hardware can be reduced, so the cost of stacks can be significantly lowered. The most advanced fuel cell stack can provide high power in a limited vehicular space owing to its high specific power. However, the specific power of stacks in China still lags behind the advanced level in the world. In this paper, the technical approaches to improving the specific power of the fuel cell stack are discussed, from the aspects of highly active catalyst, enhanced composite proton exchange membrane, high disturbance flow field, conductive and corrosion-resistant thin-metal bipolar plates, as well as assembly and consistency of stacks. Based on the accumulation of theories and from practices, the relevance between the activation/ohmic/mass transfer polarization of fuel cells and materials/components/assembly is analyzed, which provides a reference for further improving the performance and specific power of fuel cell stacks.
Keywords： fuel cell vehicle fuel cell stack performance specific power
Finite Layer Analysis of Three-Dimensional Biot Consolidation of Homogeneous Soils
Mei Guoxiong,Zai Jinmin,Zhao Weibing,Yin Jianhua
Strategic Study of CAE 2004, Volume 6, Issue 7, Pages 43-47
This paper presents a finite layer procedure for the consolidation analysis of layered soils using a cross isotropic elastic constitutive model. The program is first verified using two published results. Then using this program, the influences of cross isotropy on the consolidation behavior are analyzed. The results obtained using the cross isotropic elastic model are compared with results using isotropic elastic model. It is found that the cross isotropy has very large influences on the consolidation behavior. Curves of the average degree of consolidation are obtained and presented in the paper, which is useful for engineering practice.
Keywords： finite layer analysis Biot's consolidation three-dimension cross-an isotropic
Chengjun Zeng, Liwu Liu, Yang Du, Miao Yu, Xiaozhou Xin, Tianzhen Liu, Peilei Xu, Yu Yan, Dou Zhang, Wenxu Dai, Xin Lan, Fenghua Zhang, Linlin Wang, Xue Wan, Wenfeng Bian, Yanju Liu, Jinsong Leng
Engineering 2023, Volume 28, Issue 9, Pages 49-57 doi: 10.1016/j.eng.2023.01.005
Once China's Tianwen-1 Mars probe arrived in a Mars orbit after a seven-month flight in the deep cold space environment, it would be urgently necessary to monitor its state and the surrounding environment. To address this issue, we developed a flexible deployable subsystem based on shape memory polymer composites (SMPC-FDS) with a large folding ratio, which incorporates a camera and two temperature
telemetry points for monitoring the local state of the Mars orbiter and the deep space environment. Here, we report on the development, testing, and successful application of the SMPC-FDS. Before reaching its Mars remote-sensing orbit, the SMPC-FDS is designed to be in a folded state with high stiffness; after reaching orbit, it is in a deployed state with a large envelope. The transition from the folded state to the
deployed state is achieved by electrically heating the shape memory polymer composites (SMPCs); during this process, the camera on the SMPC-FDS can capture the local state of the orbiter from multiple angles. Moreover, temperature telemetry points on the SMPC-FDS provide feedback on the environment temperature and the temperature change of the SMPCs during the energization process. By simulating a
Mars on-orbit space environment, the engineering reliability of the SMPC-FDS was comprehensively verified in terms of the material properties, structural dynamic performance, and thermal vacuum deployment feasibility. Since the launch of Tianwen-1 on 23 July 2020, scientific data on the temperature environment around Tianwen-1 has been successfully acquired from the telemetry points on the
SMPC-FDS, and the local state of the orbiter has been photographed in orbit, showing the national flag of China fixed on the orbiter.
Keywords： Flexible deployable structure Shape memory polymer composite Mars exploration Temperature telemetry On-orbit deployment
New Cuk Matrix Converter with High Voltage Transfer Ratio
Zhang Xiaoping,Zhu Jianlin,Tang Huaping,Zhang Binggen,Liu Shasha
Strategic Study of CAE 2008, Volume 10, Issue 4, Pages 78-83
The drawback of classical matrix converter having low voltage transfer ratio is studied and a topology of a new matrix converter called as a Cuk matrix converter is proposed. The basic configuration of this new topology and its fundamental are firstly introduced, the analytic expression concerning functions relation of voltage transfer ratio to duty cycle is deduced, and the basic design method of double-loop control strategy is expounded. Finally the validity and feasibility of the new topology are tested by simulation.The results show that the output voltage and frequency can be modulated optionally by the new converter, of which the voltage transfer ratio can be greater than 1, or lower than 1, and an ideal sine wave can be directly obtained without filtering. Thus the inherent problem of classical matrix converter having low voltage transfer ratio is effectively solved by this study, which is of certain practical importance.
Keywords： Cuk matrix converter circuit topology voltage transfer ratio double-loop control simulation
Zhao Jinsheng,Tan Junling,Gu Zhengfu,Liu Xiaochun
Strategic Study of CAE 2012, Volume 14, Issue 11, Pages 88-93
Aiming at the characteristic of the formation water of Huaqing Chang 6 reservoir and taking the comprehensive foaming ability as evaluation index, 6 foaming agents were optimized. ZY-1 foaming agent was the optimal foaming agent, and the optimal foaming agent concentration and foam stabilizer concentration were 0.5 % and 764 mg/L respectively. On the basis of the foaming agent optimization result, using parallel cores with approximate permeability contrast，CO2 foam flooding experiment was simulated through 2 injection way. The experiment result showed that underground foaming way, CO2 and the foaming agent injected alternately, had higher plugging differential pressure and better displacement efficiency. The optimal injection slug combination was first 0.2 PV (pore volume) foaming agent solution and then 0.4 PV CO2 gas, and the total injected volume was 0.6 PV.
Keywords： heterogeneous reservoirs CO2 foam profile control and flooding injection parameter experimental stud
Title Author Date Type Operation
A novel method for PAPR reduction of the OFDM signal using nonlinear scaling and FM
Yi-hu Xu, Jung-Yeol Oh, Zhen-hao Sun, Myoung-Seob Lim,xuyh@ybu.edu.cn,mslim@jbnu.ac.kr
Journal Article
Controllability of Boolean control networks with multiple time delays in both states and controls
Yifeng LI, Lan WANG,liyifeng@cqnu.edu.cn,wanglan202212@126.com
Journal Article
Scheme comparison of Qiongzhou strait railway tunnel
Tan Zhongsheng,Wang Mengshu,Luo Shixiang
Journal Article
The analysis of specific energy applied in Bohai Strait tunnel during TBM construction
Gao Pan,Zou Chong
Journal Article
Jaw Crusher With Large Reduction Ratio and the Modification of Crushing Technology
Rao Qilin
Journal Article
Analysis of Influencing Factors on Transmission Ratio in Magnetic Metal Belt Transmission
Luo Shanming,Miao Xiexing
Journal Article
The Analysis on Output-input Ratio of Artificial Supplementary Energy in Agro-eco-engineering
Bian Yousheng,Liu Yingkun,Bian Jing
Journal Article
Multiscale Homogenization Analysis of Alkali–Silica Reaction (ASR) Effect in Concrete
Roozbeh Rezakhani, Mohammed Alnaggar, Gianluca Cusatis
Journal Article
Study on scheme comparison of bridge and tunnel for Bohai Strait cross-sea channel
Song Kezhi
Journal Article
Technological Approaches to Increasing Specific Power of Vehicular Fuel Cell Stacks
Hou Ming, Shao Zhigang, Yi Baolian
Journal Article
Finite Layer Analysis of Three-Dimensional Biot Consolidation of Homogeneous Soils
Mei Guoxiong,Zai Jinmin,Zhao Weibing,Yin Jianhua
Journal Article
A Shape-Memory Deployable Subsystem with a Large Folding Ratio in China’s Tianwen-1 Mars Exploration Mission
Chengjun Zeng, Liwu Liu, Yang Du, Miao Yu, Xiaozhou Xin, Tianzhen Liu, Peilei Xu, Yu Yan, Dou Zhang, Wenxu Dai, Xin Lan, Fenghua Zhang, Linlin Wang, Xue Wan, Wenfeng Bian, Yanju Liu, Jinsong Leng
Journal Article
New Cuk Matrix Converter with High Voltage Transfer Ratio
Zhang Xiaoping,Zhu Jianlin,Tang Huaping,Zhang Binggen,Liu Shasha
Journal Article
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