Two-step Holographic Imaging Method based on Single-pixel Compressive Imaging

Jun Li,Yaqing Li,Yuping Wang,Ke Li,Rong Li,Jiaosheng Li,Yangyang Pan 한국광학회 2014 Current Optics and Photonics Vol.18 No.2

We propose an experimental holographic imaging scheme combining compressive sensing (CS) theory with digital holography in phase-shifting conditions. We use the Mach-Zehnder interferometer for hologram formation, and apply the compressive sensing (CS) approach to the holography acquisition process. Through projecting the hologram pattern into a digital micro-mirror device (DMD), finally we will acquire the compressive sensing measurements using a photodiode. After receiving the data of two holograms via conventional communication channel, we reconstruct the original object using certain signal recovery algorithms of CS theory and hologram reconstruction techniques, which demonstrated the feasibility of the proposed method.

An Efficient Model Based on Smoothed ℓ₀ Norm for Sparse Signal Reconstruction

( Yangyang Li ),( Guiling Sun ),( Zhouzhou Li ),( Tianyu Geng ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.4

Compressed sensing (CS) is a new theory. With regard to the sparse signal, an exact reconstruction can be obtained with sufficient CS measurements. Nevertheless, in practical applications, the transform coefficients of many signals usually have weak sparsity and suffer from a variety of noise disturbances. What's worse, most existing classical algorithms are not able to effectively solve this issue. So we proposed an efficient algorithm based on smoothed ℓ₀ norm for sparse signal reconstruction. The direct ℓ₀ norm problem is NP hard, but it is unrealistic to directly solve the ℓ₀ norm problem for the reconstruction of the sparse signal. To select a suitable sequence of smoothed function and solve the ℓ₀ norm optimization problem effectively, we come up with a generalized approximate function model as the objective function to calculate the original signal. The proposed model preserves sharper edges, which is better than any other existing norm based algorithm. As a result, following this model, extensive simulations show that the proposed algorithm is superior to the similar algorithms used for solving the same problem.

Differential Profile of Plasma Circular RNAs in Type 1 Diabetes Mellitus

Yangyang Li,Ying Zhou,Minghui Zhao,Jing Zou,Yuxiao Zhu,Xuewen Yuan,Qianqi Liu,Hanqing Cai,Cong-Qiu Chu,Yu Liu 대한당뇨병학회 2020 Diabetes and Metabolism Journal Vol.44 No.6

Background No currently available biomarkers or treatment regimens fully meet therapeutic needs of type 1 diabetes mellitus (T1DM). Circular RNA (circRNA) is a recently identified class of stable noncoding RNA that have been documented as potential biomarkers for various diseases. Our objective was to identify and analyze plasma circRNAs altered in T1DM. Methods We used microarray to screen differentially expressed plasma circRNAs in patients with new onset T1DM (n=3) and age-/gender-matched healthy controls (n=3). Then, we selected six candidates with highest fold-change and validated them by quantitative real-time polymerase chain reaction in independent human cohort samples (n=12). Bioinformatic tools were adopted to predict putative microRNAs (miRNAs) sponged by these validated circRNAs and their downstream messenger RNAs (mRNAs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to gain further insights into T1DM pathogenesis. Results We identified 68 differentially expressed circRNAs, with 61 and seven being up- and downregulated respectively. Four of the six selected candidates were successfully validated. Curations of their predicted interacting miRNAs revealed critical roles in inflammation and pathogenesis of autoimmune disorders. Functional relations were visualized by a circRNA-miRNA-mRNA network. GO and KEGG analyses identified multiple inflammation-related processes that could be potentially associated with T1DM pathogenesis, including cytokine-cytokine receptor interaction, inflammatory mediator regulation of transient receptor potential channels and leukocyte activation involved in immune response. Conclusion Our study report, for the first time, a profile of differentially expressed plasma circRNAs in new onset T1DM. Further in silico annotations and bioinformatics analyses supported future application of circRNAs as novel biomarkers of T1DM.

Dilatation characteristics of the coals with outburst proneness under cyclic loading conditions and the relevant applications

Li, Yangyang,Zhang, Shichuan,Zhang, Baoliang Techno-Press 2018 Geomechanics & engineering Vol.14 No.5

By conducting uniaxial loading cycle tests on the coal rock with outburst proneness, the dilatation characteristics at different loading rates were investigated. Under uniaxial loading and unloading, the lateral deformation of coal rock increased obviously before failure, leading to coal dilatation. Moreover, the post-unloading recovery of the lateral deformation was rather small, suggesting the onset of an accelerated failure. As the loading rate increased further, the ratio of the stress at the dilatation critical point to peak-intensity increased gradually, and the pre-peak volumetric deformation decreased with more severe post-peak damage. Based on the laboratory test results, the lateral deformation of the coals at different depths in the #1302 isolated coal pillars, Yangcheng Coal Mine, was monitored using wall rock displacement meter. The field monitoring result indicates that the coal lateral displacement went through various distinct stages: the lateral displacement of the coals at the depth of 2-6 m went through an "initial increase-stabilize-step up-plateau" series. When the coal wall of the working face was 24-18 m away from the measuring point, the coals in this region entered the accelerated failure stage; as the working face continued advancing, the lateral displacement of the coals at the depth over 6 m increased steadily, i.e., the coals in this region were in the stable failure stage.

Research on the Operation Situation and Path of Large-scale Stadiums under the Normalization of the Epidemic -Take Wuhan Sports Center as an Example-

Yangyang Li,Yang Jimei 아시아건강운동학회 2022 Journal of Asian Society for Health & Exercise Vol.4 No.1

PURPOSE : Under the normalization of the epidemic, in the current sports industry, the operation of stadiums with enormous investment is a major problem that needs to be solved urgently. Using literature, case analysis, expert interviews, field research, and other research methods, taking Wuhan Sports Center as an example, research finds that under the normalization of the epidemic. METHODS : 1. Epidemics lead to the uncertainty of the event; 2. The scale of the sports industry is limited and easily affected; 3. More complete policies at the national level; 4. The enthusiasm of people to participate in sports is even higher. Large-scale stadiums have questions bellow. RESULTS : 1. Multifunctional utilization needs to be strengthened; 2. Market-oriented operation needs to be improved; 3. Economic benefits are difficult to balance social benefits; 4. Domestic and foreign reputation needs to be improved. Suggested large-scale stadiums in terms of operation. CONCLUSIONS : 1. Expand the function of the stadium, create intelligent stadiums; 2. Promote the innovation of operating model, generate revenue through market flexibility; 3. Mitigate losses and improve multiple incomes to balance the benefits; 4. Relying on the urban characteristics to create a fashion sports experience center.

Single-switch boost converter with extremely high step-up voltage gain

Hao, Yangyang,Li, Haibin,Li, Kai,Fang, Chengqun,Ding, Xinping The Korean Institute of Power Electronics 2020 JOURNAL OF POWER ELECTRONICS Vol.20 No.6

This paper presents a single-switch high-voltage gain DC-DC converter with a coupled-inductor. The proposed converter overcomes the drawbacks of traditional DC-DC converters such as insufficient boost capability and high stress on the devices. Its advantages include having a small number of switch devices, low voltage stress on the switch, and a high voltage gain. This paper analyzes the operating modes of the proposed converter in detail and derives the voltage/current stresses on the components. The efficiency of the converter and the power dissipation distribution are quantitatively studied. To verify the efficiency and feasibility of the proposed converter, a 200 W prototype was built in the laboratory. Experimental results obtained from the prototype match well with the theoretical analysis. The highest efficiency is equal to 95.82%, which can be obtained at half of the rated output power.

Network Security Prediction Method Based on Kalman Filtering Fusion Decision Entropy Theory

Yunfa Li,Mingyi Li,Yangyang Shen 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.12

Network security situation prediction is of great significance for the use of the Internet, and it is the focus of production and life issues. Under the guidance of the model combination forecasting method, In this paper, based on the Kalman filtering model a new method of network security prediction is presented, which is based on the theory of decision entropy. In this method, the Kalman state equation and measurement equation are constructed according to the key attributes of the network security state, and then combined with the decision entropy theory to predict the future state of network security. The experimental results show that the proposed method has high prediction accuracy and is suitable for the state prediction of network security.

Optimal Configuration and Economic Operation of Wind–Solar-Storage Complementary System for Agricultural Irrigation in Mountainous Areas

Li Bin,Zhao Jianing,Zhang Yangyang,Bai Xiaoqing 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.4

The disorderly use of electricity in agriculture is a serious source of the current electricity tension, and as distributed energy is expediently promoted, it is becoming increasingly notable that the source network and load are not well coordinated. Small pumped storage power station is established in this paper using irrigation facilities and mountain height differences. On the basis of satisfying the electricity demand for irrigation, the capacity of pumping units and generating sets is configured prudently with wind farms and photovoltaic power stations. In addition, fluctuation smoothing is factored into consideration, the spectrum analysis method is utilized to calibrate the installed capacity. We develop a wind-solar-pumped storage complementary day-ahead dispatching model with the objective of minimizing the grid connection cost by taking into account the uncertainty of wind power and photovoltaic output and combining the complementary characteristics. The proposed model and method were validated through simulation on four typical days for a microgrid system. The simulation results demonstrate that the system fully utilizes new energy sources and successfully addresses the issue of water and electricity consumption for agricultural irrigation in mountainous regions. This system also offers a valuable concept for achieving low carbon and environmental protection for agricultural electricity consumption.

Quantification of the Energy Flows during Ultrasonic Wire Bonding under Different Process Parameters

Yangyang Long,Friedrich Schneider,Chun Li,Jörg Hermsdorf,Jens Twiefel,Jörg Wallaschek 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.6 No.3

Despite of its wide and long-term application for interconnections in the field of microelectronics packaging, a quantitative understanding on the mechanisms of ultrasonic (US) wire bonding is still lacked. In this work, the energy flows from the electrical input energy to the different mechanisms during the US bonding process are quantified based on real-time observations via which the relative motions at the wire/substrate and the wire/tool interfaces can be detected. The relative motions at the two interfaces are proved to be caused by both the continuous plastic deformation and the US vibration. The normal force and US power interdependently affect the relative motion amplitudes. The deduced energy flows show that the energy from the transducer mainly flows to the vibration induced friction at the two interfaces and the microwelds formation, deformation and breakage. Despite of their significance to the process, the other mechanisms receive only little amount of energy. The impacts of the process parameters including normal force, US power and time on the energy flows are quantitatively investigated. A good coupling of the normal force and the US power guides more energy to the formation of microwelds while a long process time would increase the friction induced energy consumption.

A Stable Iteration Procedure of Newton’s Method in Finite-Element Computation of Nonlinear Magnetic Field Problems With a Vector Hysteresis Model

Li, Wei,Fu, Weinong,Koh, Chang-Seop,Wang, Yangyang IEEE 2017 IEEE transactions on magnetics Vol.53 No.2

<P>A stable iteration algorithm for solving nonlinear magnetic field problems using the finite-element method (FEM), incorporating a vector Jiles-Atherton hysteresis model and Newton's method, is introduced. The Jacobian matrix is calculated according to the information of the differential reluctivity of the hysteresis loops. In order to balance the FEM computation stability and efficiency, two time criteria are adopted. The proposed FEM procedure is applied to analyze a three-phase transformer made of electrical steel sheets. The numerical computation is stable and fast. The numerically computation results are compared with the experimentally measured ones. The computation efficiency and accuracy proves the effectiveness of the proposed algorithm.</P>