新冠肺炎疫情期间两个舆论场修辞幻象探析

??梅(ZHAO-Hongmei) 동아인문학회 2020 동아인문학 Vol.52 No.-

The paper reviews some reports with significant difference on the epidemic in the official media and the social media, during the serious period of the COVID-19 from distinct perspectives based on their respective positions and communication ways, and believes that the two constructed completely different and complementary rhetorical vision, from which the audiences obtain a relatively complete understanding about the actual epidemic world from media’s words. In the end, the article compares the features of reports between the official and the social, and the Chinese and some foreigners’ media and attributes their differences to the culture.

Testicular Characteristics and the Block to Spermatogenesis in Mature Hinny

Han, Hongmei,Wang, Aihong,Liu, Liming,Zhao, Gaoping,Su, Jie,Wang, Biao,Li, Yunxia,Zhang, Jindun,Wu, Baojiang,Sun, Wei,Hu, Shuxiang,Li, Shuyu,Zhao, Lixia,Li, Xihe Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.6

Most hinnies (female donkey${\times}$male horse) and mules (female horse${\times}$male donkey) are sterile with few reports of equine fertile hybrids. The main cause of this sterility is thought to be a meiotic block to spermatogenesis and oogenesis. This study compared the developmental features of the testes and a histological analyses of spermatogenesis in a male hinny with those of a normal, fertile stallion and Jack donkey. Hinny testes showed a thicker tunica albuginea, fewer blood vessels and more connective tissue in the testis parenchyma than those of the stallion and Jack donkey. Although the mean number of seminiferous tubules was significantly higher in stallion and hinny than Jack donkey (p<0.01), the mean proportion of seminiferous tubules was lower in the hinny (p<0.01) which resulted in a smaller diameter of seminiferous tubules. The mean number of spermatogonia and spermatocytes per unit area were significantly lower in hinny testis (p<0.01) and no spermatids or mature spermatozoa cells were found during immunofluorescent analyses. These results indicated that defects in seminiferous tubule development and structure occur in the testis of hinnies. Furthermore, most spermatogonia and spermatocytes cease development in synapsis during mid-meiosis of spermatocytes, which results in a block to spermatogenesis that prevents the formation of spermatids and matured spermatozoa during meiosis in male hinnies.

Double-Objective Finite Control Set Model-Free Predictive Control with DSVM for PMSM Drives

Zhao, Beishi,Li, Hongmei,Mao, Jingkui The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.1

Discrete space vector modulation (DSVM) is an effective method to improve the steady-state performance of the finite control set predictive control for permanent magnet synchronous motor drive systems. However, it requires complex computations due to the presence of numerous virtual voltage vectors. This paper proposes an improved finite control set model-free predictive control using DSVM to reduce the computational burden. First, model-free deadbeat current control is used to generate the reference voltage vector. Then, based on the principle that the voltage vector closest to the reference voltage vector minimizes the cost function, the optimal voltage vector is obtained in an effective way which avoids evaluation of the cost function. Additionally, in order to implement double-objective control, a two-level decisional cost function is designed to sequentially reduce the stator currents tracking error and the inverter switching frequency. The effectiveness of the proposed control is validated based on experimental tests.

Rapid visual detection of Mycobacterium avium subsp. paratuberculosis by recombinase polymerase amplification combined with a lateral flow dipstick

Guimin Zhao,Hongmei Wang,Peili Hou,Chengqiang He,Hongbin He 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.2

Paratuberculosis (Johne’s disease) is a chronic debilitating disease of domestic and wild ruminants. However, widespread point-of-care testingis infrequent due to the lack of a robust method. The isothermal recombinase polymerase amplification (RPA) technique has applied for rapiddiagnosis. Herein, RPA combined with a lateral flow dipstick (LFD) assay was developed to estimate DNA from Mycobacterium avium subsp. paratuberculosis. First, analytical specificity and sensitivity of the RPA-nfo primer and probe sets were assessed. The assay successfullydetected M. paratuberculosis DNA in 30 min at 39oC with a detection limit of up to eight copies per reaction, which was equivalent to thatof the real-time quantitative polymerase chain reaction (qPCR) assay. The assay was specific, as it did not amplify genomes from five otherMycobacterium spp. or five pathogenic enteric bacteria. Six hundred-twelve clinical samples (320 fecal and 292 serum) were assessed byRPA-LFD, qPCR, and enzyme-linked immunosorbent assay, respectively. The RPA-LFD assay yielded 100% sensitivity, 97.63% specificity,and 98.44% concordance rate with the qPCR results. This is the first report utilizing an RPA-LFD assay to visualize and rapidly detect M. paratuberculosis. Our results show this assay should be a useful method for the diagnosis of paratuberculosis in resource-constrained settings.

Double-Objective Finite Control Set Model-Free Predictive Control with DSVM for PMSM Drives

Beishi Zhao,Hongmei Li,Jingkui Mao 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.1

Discrete space vector modulation (DSVM) is an effective method to improve the steady-state performance of the finite controlset predictive control for permanent magnet synchronous motor drive systems. However, it requires complex computations dueto the presence of numerous virtual voltage vectors. This paper proposes an improved finite control set model-free predictivecontrol using DSVM to reduce the computational burden. First, model-free deadbeat current control is used to generate thereference voltage vector. Then, based on the principle that the voltage vector closest to the reference voltage vector minimizesthe cost function, the optimal voltage vector is obtained in an effective way which avoids evaluation of the cost function. Additionally, in order to implement double-objective control, a two-level decisional cost function is designed to sequentiallyreduce the stator currents tracking error and the inverter switching frequency. The effectiveness of the proposed control isvalidated based on experimental tests.

Fatigue life prediction and reliability analysis of the forage crusher rotor

Haixu Zhao,Zhiping Zhai,Yingsheng Mou,Le Liu,Yuezheng Lan,Hongmei Cui 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.4

To accurately predict fatigue life and reliability of the forage crusher rotor, the stress load spectrum of the rotor is obtained via the two-way fluid-structure coupling method, which calculates the coupled flow field in the forage crusher and rotor structure. The fatigue life of the rotor is predicted, and its reliability is analyzed. Finally, the rotor is optimized by a multiisland genetic algorithm. The results indicate that the fatigue life prediction based on fracture mechanics theory and the Gerber average stress correction method is more suitable for the prediction of the rotor’s fatigue life. After optimization, the fatigue life cycles of the rotor are increased from 1.229×10 8 to 7.67×10 8 and the reliability is increased from 89.4 % to 99.7 %. This meets the reliability requirement of key parts of agricultural and animal husbandry machinery. This study provides a reference for the prediction and optimization of fatigue life and reliability of forage crushers.

The Application of Atmospheric Plasma for Cotton Fabric Desizing

Xuemei Wang,Hongmei Zhao,Fuxing Chen,Xin Ning,Shaojuan Chen,Qunli Guan,Shouxiang Jiang,Dagang Miao 한국섬유공학회 2019 Fibers and polymers Vol.20 No.11

Production process of cotton fabric involves numerous water and chemical consumptions, causing serious energywaste and environmental problem. In this study, a waterless atmospheric plasma treatment (APT) was applied on cottonfabric to desize the starch coated in the weaving process. Plasma parameters, i.e., plasma voltage, plasma duty cycle andoxygen flow rate, are varied in order to systematically evaluate their influence on fabric physical properties such as theimpurity removal, whiteness, capillary effect, tensile strength and breaking elongation of fabric. Optimal plasma parametersfor oxygen APT were determined, with plasma voltage of 320 V, plasma duty cycle of 60 % and oxygen flow rate of 1000 l/h. The APT desizing method attained comparable fabric performances with the traditional amylase desizing method. The resultswere further supported by the scanning electron microscope (SEM) and Fourier transfer infrared spectroscopy (FTIR)investigations.

Discrete Terminal Integral Sliding-Mode Backstepping Speed Control of SMPMSM Drives Based on Ultra-Local Mode

Huang Jiandong,Li Hongmei,Yang Liguo,Zhao Haonan,Zhang Peng 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.4

In this paper, a novel discrete terminal integral sliding-mode backstepping control (DTISM-BSC) is proposed for the surface-mounted permanent magnet synchronous motor (SMPMSM) drive system, which improves the speed tracking performance and robustness of the system. In this control scheme, the discrete ultra-local model (ULM) of the SMPMSM drives, which employs the algebraic parameter identification technology to handle the unknown disturbance and parametric uncertainties, is first set up. Then, the terminal integral sliding-mode surface is proposed for its advantages of finite-time convergence to achieve speed rapid tracking, in which the control performance of backstepping control is improved. Thirdly, the equivalent control law is combined with the designed switching law to construct the speed controller based on the ULM. In this case, the bounded function is adopted to improve chattering problem. Meanwhile, the asymptotic stability and rapid convergence is verified. Finally, the experimental comparisons between the proposed method and the non-singular terminal sliding mode backstepping control (NTSM-BSC) are developed to validate the effectiveness of the proposed DTISM-BSC.

Changes in force associated with the amount of aligner activation and lingual bodily movement of the maxillary central incisor

Xiaowei Li,Chaochao Ren,Zheyao Wang,Pai Zhao,Hongmei Wang,Yuxing Bai 대한치과교정학회 2016 대한치과교정학회지 Vol.46 No.2

Objective: The purposes of this study were to measure the orthodontic forces generated by thermoplastic aligners and investigate the possible influences of different activations for lingual bodily movements on orthodontic forces, and their attenuation. Methods: Thermoplastic material of 1.0-mm in thickness was used to manufacture aligners for 0.2, 0.3, 0.4, 0.5, and 0.6 mm activations for lingual bodily movements of the maxillary central incisor. The orthodontic force in the lingual direction delivered by the thermoplastic aligners was measured using a micro-stress sensor system for the invisible orthodontic technique, and was monitored for 2 weeks. Results: Orthodontic force increased with the amount of activation of the aligner in the initial measurements. The attenuation speed in the 0.6 mm group was faster than that of the other groups (p < 0.05). All aligners demonstrated rapid relaxation in the first 8 hours, which then decreased slowly and plateaued on day 4 or 5. Conclusions: The amount of activation had a substantial influence on the orthodontic force imparted by the aligners. The results suggest that the activation of lingual bodily movement of the maxillary central incisor should not exceed 0.5 mm. The initial 4 or 5 days is important with respect to orthodontic treatment incorporating an aligner.

A Multiscale Analysis Method for Predicting the Transverse Mechanical Properties of Unidirectional Fibre-reinforced Composites

Wenbin Jia,Lei Fang,Zhi Chen,Kai Zhao,Hongmei Huang,Lei Pan 한국섬유공학회 2020 Fibers and polymers Vol.21 No.6

Mechanical property prediction methods for composites are very important as theoretical tools for engineeringstructural design. To more accurately capture the transverse mechanical properties of composites, a multiscale analysismethod is developed in this paper. The multiscale analysis method includes three scales: (1) At the microscale, a microscopiccohesive model based on atomic potential energy is established for the interface; (2) At the mesoscale, a unit cell model isestablished for the fibre, matrix and interface; and (3) At the macroscale, the homogenization method, failure criteria anddamage degradation models are used for predicting the transverse mechanical properties. Subsequently, the transversemechanical properties and the damage evolution process are simulated with the multiscale analysis method. A comparisonbetween the simulations and experiments shows that the maximum error of the predicted transverse modulus and transversestrength is -4.45 % and -12.05 %, respectively. Finally, the effects of the interfacial strength on the macroscopic transversemechanical properties and the damage onset are analysed. The following conclusions are drawn from the simulation results:(1) The interfacial strength has a more significant effect on the transverse strength and ultimate strain than on the transversemodulus; (2) Decreasing the interfacial strength has a greater effect on the transverse modulus, strength and ultimate strainthan increasing the interfacial strength; and (3) The interfacial strength can change the damage onset.