• Title/Summary/Keyword: Changchun

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A novel heuristic for handover priority in mobile heterogeneous networks based on a multimodule Takagi-Sugeno-Kang fuzzy system

  • Zhang, Fuqi;Xiao, Pingping;Liu, Yujia
    • ETRI Journal
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    • v.44 no.4
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    • pp.560-572
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    • 2022
  • H2RDC (heuristic handover based on RCC-DTSK-C), a heuristic algorithm based on a highly interpretable deep Takagi-Sugeno-Kang fuzzy classifier, is proposed for suppressing the mobile heterogeneous networks problem of frequent handover and handover ping-pong in the multibase-station scenario. This classifier uses a stack structure between subsystems to form a deep classifier before generating a base station (BS) priority sequence during the handover process, and adaptive handover hysteresis is calculated. Simulation results show that H2RDC allows user equipment to switch to the best antenna at the optimal time. In high-BS density load and mobility scenarios, the proposed algorithm's handover success rate is similar to those of classic algorithms such as best connection (BC), self tuning handover algorithm (STHA), and heuristic for handover based on AHP-TOPSIS-FUZZY (H2ATF). Moreover, the handover rate is 83% lower under H2RDC than under BC, whereas the handover ping-pong rate is 76% lower.

Edge Computing Task Offloading of Internet of Vehicles Based on Improved MADDPG Algorithm

  • Ziyang Jin;Yijun Wang;Jingying Lv
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.2
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    • pp.327-347
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    • 2024
  • Edge computing is frequently employed in the Internet of Vehicles, although the computation and communication capabilities of roadside units with edge servers are limited. As a result, to perform distributed machine learning on resource-limited MEC systems, resources have to be allocated sensibly. This paper presents an Improved MADDPG algorithm to overcome the current IoV concerns of high delay and limited offloading utility. Firstly, we employ the MADDPG algorithm for task offloading. Secondly, the edge server aggregates the updated model and modifies the aggregation model parameters to achieve optimal policy learning. Finally, the new approach is contrasted with current reinforcement learning techniques. The simulation results show that compared with MADDPG and MAA2C algorithms, our algorithm improves offloading utility by 2% and 9%, and reduces delay by 29.6%.

Rare earth oxide luminescence materials via electrospinning: synthesis and characteristics

  • Hou, Zhiyao;Lin, Jun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.200-203
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    • 2009
  • One-dimensional rare earth oxide luminescence nano materials have been prepared by a combination method of sol-gel process and electrospinning. Systematic studie s on optical properties indicate that electrospinning is a facile and novel route for development luminescen ce materials that are useful in fluorescent lamps an d field emission dispalys.

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Molecular Characterization of Enterocytozoon bieneusi in Domestic Rabbits (Oryctolagus cuniculus) in Northeastern China

  • Zhang, Xiao-Xuan;Jiang, Jing;Cai, Ya-Nan;Wang, Chun-Feng;Xu, Peng;Yang, Gui-Lian;Zha, Quan
    • Parasites, Hosts and Diseases
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    • v.54 no.1
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    • pp.81-85
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    • 2016
  • A study of 426 rabbits from 3 cities in Jilin province (Changchun City and Jilin City) and Liaoning province (Shenyang City) was conducted between May and June 2015. The overall prevalence of E. bieneusi in rabbits was 0.94% (4/426), with 0% (0/116), 1.72% (3/174), and 0.74% (1/136) in Jilin, Changchun, and Shenyang City, respectively. Only 3 farms (farm 1 and farm 3 in Changchun City, farm 8 in Shenyang City) were PCR-positive for E. bieneusi. Moreover, rabbits of more than 6 months (1.72%) had the highest E. bieneusi prevalence, followed by rabbits of 4-6 months (1.26%), 2-3 months (0.58%), and less than 1 month (0%). Analysis of ITS gene of E. bieneusi suggested that all 4 E. bieneusi isolates were genotype D, and were classified as group 1a. The present results first demonstrated the existence of zoonotic E. bieneusi in domestic rabbits in China. Effective control measures should be implemented to prevent E. bieneusi infection in domestic rabbits, other animals, and humans.

A Study on Information Consumption Behavior Structure of Rural Residents in Changchun, China (중국 장춘시 농촌주민의 정보소비 행동구조에 관한 연구)

  • Liu, Hui-Shu;Jung, Gi-Young;Kim, Hyung-Ho
    • Journal of the Korea Convergence Society
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    • v.11 no.1
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    • pp.9-16
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    • 2020
  • This study aims to deeply analyze the information consumption behavior structure of rural residents in Changchun, China. and further improve the information consumption level of rural residents. Questionnaire survey and statistical analysis were used in this study. First, Through in-depth interview and open questionnaire collection and compilation of measurement questions. Secondly, residents in 15 rural areas around Changchun were selected for the survey, Finally, SPSS23.0 was used for exploratory factor analysis of recovered data, and Mplus7.4 was used for confirmatory factor analysis. The results show that the structure of information consumption behavior of rural residents in Changchun includes three dimensions of information demand, information literacy and payment ability, which is corresponding to the previous studies on information consumption behavior structure's demand power, purchasing power and information quality. This study has certain empirical validity.

hARIP2 is a Putative Growth-promoting Factor Involved in Human Colon Tumorigenesis

  • Gao, Rui-Feng;Li, Zhan-Dong;Jiang, Jing;Yang, Li-Hua;Zhu, Ke-Tong;Lin, Rui-Xin;Li, Hao;Zhao, Quan;Zhang, Nai-Sheng
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.20
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    • pp.8581-8586
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    • 2014
  • Activin is a multifunctional growth and differentiation factor of the growth factor-beta (TGF-${\beta}$) superfamily, which inhibits the proliferation of colon cancer cells. It induces phosphorylation of intracellular signaling molecules (Smads) by interacting with its type I and type II receptors. Previous studies showed that human activin receptor-interacting protein 2 (hARIP2) can reduce activin signaling by interacting with activin type II receptors; however, the activity of hARIP2 in colon cancer has yet to be detailed. In vitro, overexpression of hARIP2 reduced activin-induced transcriptional activity and enhanced cell proliferation and colony formation in human colon cancer HCT8 cells and SW620 cells. Also, hARIP2 promoted colon cancer cell apoptosis, suggesting that a vital role in the initial stage of colon carcinogenesis. In vivo, immunohistochemistry revealed that hARIP2 was expressed more frequently and much more intensely in malignant colon tissues than in controls. These results indicate that hARIP2 is involved in human colon tumorigenesis and could be a predictive maker for colon carcinoma aggressiveness.

Design and Manufacture of an Off-axis Aluminum Mirror for Visible-light Imaging

  • Zhang, Jizhen;Zhang, Xin;Tan, Shuanglong;Xie, Xiaolin
    • Current Optics and Photonics
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    • v.1 no.4
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    • pp.364-371
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    • 2017
  • Compared to one made of glass, an aluminum mirror features light weight, compact design, low cost, and quick manufacturing. Reflective mirrors and supporting structures can be made from the same material, to improve the athermal performance of the system. With the rapid development of ultraprecise machining technologies, the field of applications for aluminum mirrors has been developed rapidly. However, most of them are rotationally symmetric in shape, and are used for infrared applications. In this paper, the design and manufacture of an off-axis aluminum mirror used for a three-mirror-anastigmat (TMA) optical system at visible wavelengths is presented. An optimized, lightweight design provides a weight reduction of more than 40%, while the surface deformation caused by earth's gravity can meet the required tolerance. The two pieces of an off-axis mirror can be diamond-turned simultaneously in one setup. The centrifugal deformation of the off-axis mirror during single-point diamond turning (SPDT) is simulated through the finite-element method (FEM). The techniques used to overcome centrifugal deformation are thoroughly described in this paper, and the surface error is reduced to about 1% of the original value. After post-polishing, the form error is $1/30{\lambda}$ RMS and the surface roughness is better than 5 nm Ra, which can meet the requirements for visible-light imaging.

Picosecond Mid-Infrared 3.8 ㎛ MgO:PPLN Optical Parametric Oscillator Laser with High Peak Power

  • Chen, Bing-Yan;Wang, Yu-Heng;Yu, Yong-Ji;Jin, Guang-Yong
    • Current Optics and Photonics
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    • v.5 no.2
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    • pp.186-190
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    • 2021
  • In this study, a compact, picosecond, mid-infrared 3.8 ㎛ MgO:PPLN optical parametric oscillator (OPO) laser output with high peak power is realized using a master oscillator power amplifier (MOPA) 1 ㎛ solid-state laser seeded by a picosecond fiber laser as the pump source. The pump source was a 50 MHz and 10 ps fiber seed source. After AOM pulse selection and two-stage solid-state amplification, a 1,064 nm laser output with a repetition frequency of 1-2 MHz, pulse width of 9.5 ps, and a maximum average power of 20 W was achieved. Furthermore, a compact short cavity with a unsynchronized pump is adopted through the design of an OPO cavity structure. When the injection pump power was 15 W and the repetition frequency was 1 MHz, the average output power of idler light was 1.19 W, and the corresponding peak power was 119 kW. The optical conversion efficiency was 7.93%. When the repetition frequency was increased to 2 MHz, the average output power of idler light was 1.63 W, the corresponding peak power was 81.5 kW, and the optical conversion efficiency was 10.87%. At the same time, the output wavelength was measured at 3,806 nm, and the beam quality was MX2 = 3.21 and MY2 = 3.34.

A Wide Dynamic Range NUC Algorithm for IRCS Systems

  • Cai, Li-Hua;He, Feng-Yun;Chang, Song-Tao;Li, Zhou
    • Journal of the Korean Physical Society
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    • v.73 no.12
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    • pp.1821-1826
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    • 2018
  • Uniformity is a key feature of state-of-the-art infrared focal planed array (IRFPA) and infrared imaging system. Unlike traditional infrared telescope facility, a ground-based infrared radiant characteristics measurement system with an IRFPA not only provides a series of high signal-to-noise ratio (SNR) infrared image but also ensures the validity of radiant measurement data. Normally, a long integration time tends to produce a high SNR infrared image for infrared radiant characteristics radiometry system. In view of the variability of and uncertainty in the measured target's energy, the operation of switching the integration time and attenuators usually guarantees the guality of the infrared radiation measurement data obtainted during the infrared radiant characteristics radiometry process. Non-uniformity correction (NUC) coefficients in a given integration time are often applied to a specified integration time. If the integration time is switched, the SNR for the infrared imaging will degenerate rapidly. Considering the effect of the SNR for the infrared image and the infrared radiant characteristics radiometry above, we propose a-wide-dynamic-range NUC algorithm. In addition, this essasy derives and establishes the mathematical modal of the algorithm in detail. Then, we conduct verification experiments by using a ground-based MWIR(Mid-wave Infared) radiant characteristics radiometry system with an Ø400 mm aperture. The experimental results obtained using the proposed algorithm and the traditional algorithm for different integration time are compared. The statistical data shows that the average non-uniformity for the proposed algorithm decreased from 0.77% to 0.21% at 2.5 ms and from 1.33% to 0.26% at 5.5 ms. The testing results demonstrate that the usage of suggested algorithm can improve infrared imaging quality and radiation measurement accuracy.

Analysis of the Influence of Atmospheric Turbulence on the Ground Calibration of a Star Sensor

  • Xian Ren;Lingyun Wang;Guangxi Li;Bo Cui
    • Current Optics and Photonics
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    • v.8 no.1
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    • pp.38-44
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    • 2024
  • Under the influence of atmospheric turbulence, a star's point image will shake back and forth erratically, and after exposure the originally small star point will spread into a huge spot, which will affect the ground calibration of the star sensor. To analyze the impact of atmospheric turbulence on the positioning accuracy of the star's center of mass, this paper simulates the atmospheric turbulence phase screen using a method based on a sparse spectrum. It is added to the static-star-simulation device to study the transmission characteristics of atmospheric turbulence in star-point simulation, and to analyze the changes in star points under different atmospheric refractive-index structural constants. The simulation results show that the structure function of the atmospheric turbulence phase screen simulated by the sparse spectral method has an average error of 6.8% compared to the theoretical value, while the classical Fourier-transform method can have an error of up to 23% at low frequencies. By including a simulation in which the phase screen would cause errors in the center-of-mass position of the star point, 100 consecutive images are selected and the average drift variance is obtained for each turbulence scenario; The stronger the turbulence, the larger the drift variance. This study can provide a basis for subsequent improvement of the ground-calibration accuracy of a star sensitizer, and for analyzing and evaluating the effect of atmospheric turbulence on the beam.