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“I Don’t Dare to Buy Your Nut Cake!”: Uyghur’s Image in China’s Media in the Post-2009 Era
Qichao Wang 건국대학교 아시아·디아스포라 연구소 2017 International Journal of Diaspora&Cultural Critici Vol.7 No.2
The Uyghur people are one of the fifty-five ethnic groups in China and one of the ten Islamic ethnic groups in Xinjiang, China, where they are dramatically visible and live in a concentrated region in Northwest China. The July 2009 Urumqi Riots marked the first Xinjiangrelated large-scale riots in the 21st century, and coverage of these riots provided the first exposure to audiences in China proper about the riots. Yet China’s media subsequent reporting on this riot generated a series of problems related to the identity issue, public opinion of the Uyghur, and a rising sense of fear. The rioters were depicted in the newspaper as “Xinjiang people” (Xinjiang resident, 新疆人), “Uyghur people” (Weiwu’er ren, 维吾尔人or Weizu ren 维族人), and Han-Chinese Xinjiang residents (Hanzu resident in Xinjiang,新疆汉族人). This paper presents several typical case studies in China’s media regarding reports of Uyghur-related news to answer the following research questions: How did China’s media forge and subsequently navigate the identity-orientation concepts? How did they change the semiotic of the Uyghur people” in China’s media reports, such as “Kabab seller” and “Xinjiang nut cake dealer,” which represented the Uyghur people, from a neutral semiotic to a negative connotation. Finally, how was Uyghur-phobia created from an actual scene, generating a perceived threat?
Hybrid DC circuit breaker with reduced fault isolation time and current limiting capability
Qichao Chen,Bingkun Li,Laicheng Yin,Junyuan Zheng,Zhaoyu Duan,Yiqi Liu 전력전자학회 2024 JOURNAL OF POWER ELECTRONICS Vol.24 No.1
DC circuit breakers (DCCBs) are key pieces of equipment to ensure the safe and stable operation of DC grids. However, current DCCB schemes generally have problems such as a slow fault clearing speed and a poor current limiting effect. This paper proposes a current-limited hybrid DC circuit breaker (CLHCB) that limits fault current and has fast fault isolation, which reduces the capacity requirements. The current limiting inductor in the fault current limiter (FCL) provides the current limiting capability. In addition, the energy dissipation circuit (EDC) is in parallel to reduce the energy dissipation in metal oxide arresters (MOAs) and to decrease the fault isolation time (FIT), which can reduce the thermal effects of MOAs and improve their reliability. Simulation results verify the working principle and advantages of the proposed CLHCB. When compared to an ABB HCB under the same simulation parameters, the CLHCB enables fault current limiting and faster fault isolation. Finally, experiments have verified the effectiveness of the proposed CLHCB.
Silica nanoparticles as a high-performance filtrate reducer for foam fluid in porous media
Qichao Lv,Zhaomin Li,Binfei Li,Dashan Shi,Chao Zhang,Binglin Li 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.45 No.-
During the fracturing operations for oils and gases, not only the oil and gas reservoirs, but also the nearbycivil aquifers are often polluted by the invasion of fracturing fluid filtrates. In this study, we investigatedthe potential of silica nanoparticles as a high-performance filtrate reducer for a foam fluid in a porousmedia. First, the three factors affecting filtration reduction using nanoparticles, i.e., surface rheology,foam slipping, and foam stability, were described. Then, the foam filtration through a porous media inthe core was measured using a dynamic fluid-loss device, and the effects of foam quality, pressure drop,and core permeability on the performance of the filtrate reducer were evaluated. The difficulty ofbubbles flowing from a throat to a pore in a porous media was described by resistance gradientcoefficient Cf, which is a combination of surface tension and viscoelastic modulus and increases byadding nanoparticles. Nanoparticles improve the roughness of the SiO2/sodium dodecyl benzenesulfonate foam film surface, thus increasing the slipping resistance Fslip when foams flowon the wall of athroat in a porous media. For the foams in a porous media, the diffusion of bubbles decreased in thepresence of nanoparticles, and the growth rate of gas bubble size also decreased, thus increasing thefoam resistance to gas channeling. The results of core filtration tests indicate that the fluid-loss-controlproperties increased with foam quality ranging from 0 to 85%, and the negative effects of pressure dropand permeability increase to foam filtration were weakened by adding SiO2 nanoparticles. Thus, silicananoparticles can be used as a high-performance filtrate reducer for a foam fluid in a porous media.
Underwater contactless wet‑mateable connector using bowl‑shaped coils
Qichao Zhao,Tianlei Wang,Hui Zhi,Xin Wu,Yurui Zhang,Canjun Yang,Yanhu Chen 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.7
Wet-mateable connectors enabling power and communication for underwater equipment are greatly favored for underwater systems. However, conventional underwater wet-mateable connectors with electrical contact conductors have the features of high cost, limited mate/de-mate times, and high risk of ground faults when being applied underwater, which limits their used. In this paper, a contactless underwater wet-mateable connector with bowl-shaped couplers was proposed, and an equivalent circuit for inductive power transmission was modeled and analyzed. Then the mathematical expression of the magnetic induction intensity of the bowl-shaped coil was derived. The parameters including co , zco , and s0 of the coil were analyzed and optimized to attain better performance and lower cost. A prototype was built and tested. Results showed that it can transmit power up to 1125 W with an efficiency of 85%. In addition, it can achieve a data rate up to 6 MB/s under a water pressure of 20 MPa.
Optimal Control with Terminal State Constraints for Multichannel Input Linear Systems
Qichao Sun,Juanjuan Xu,Huanshui Zhang 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.10
This paper is concerned with the linear quadratic (LQ) control problem with multiple input channels and terminal state constraints. The problem can be solved by augmenting all the inputs into one. However, the calculation will be much more involved especially for the case with large scale of inputs. To overcome this complexity, we adopt a leader-follower game theory approach. The optimal controller is obtained in the feedback of the state in terms of Riccati equations. A numerical example is provided to demonstrate the effectiveness of the derived result.
Yiqi Liu,Qichao Chen,Ningning Li,Bing Xie,Jianze Wang,Yanchao Ji 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1
In this study, we first briefly introduce the effect of circulating current control on the modulation signal of a modular multilevel converter (MMC). The maximum modulation index is also theoretically derived. According to the optimal modulation index analysis and the model in the continuous domain, different DC-side output impedance equivalent models of MMC with/without compensating component are derived. The DC-side impedance of MMC inverter station can be regarded as a series xR + yL + zC branch in both cases. The compensating component of the maximum modulation index is also related to the DC equivalent impedance with circulating current control. The frequency characteristic of impedance for MMC, which is observed from its DC side, is analyzed. Finally, this study investigates the prediction of the DC voltage ripple transfer between two-terminal MMC high-voltage direct current systems under unbalanced conditions. The rationality and accuracy of the impedance model are verified through MATLAB/Simulink simulations and experimental results.
Effect Factor Analysis of Spraying Quality for Agricultural Chemicals
Wenfeng Sun,Qichao Li,Yongcun Fan,Yanhua Wan,Teng Wang,Baozhong Cong 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.11
As one of the most important parts of the agricultural work, agricultural chemicals spray is to protect the plants from weeds, pest and bacteria. With development of high efficient agricultural chemicals, the consumption of agricultural chemicals should be controlled within a couple of liter per hectare in theory. But it’s very hard to realize effective use of agricultural chemicals in fact. In this paper, the most effect factors of spray quality such as droplets size, environment temperature, droplets density, nozzle type and spray method were analyzed in agricultural chemicals spray operation. Droplet size effects drift and uniformity of droplet distribution directly. Environment temperature effects drift and uniformity of droplet distribution greatly. Character of nozzle affects spraying quality directly. All research of the paper can offer valuable reference to appropriate application of agricultural chemicals.
Shuo Yuan,Qichao Wu,Lei Zang,Ning Fan,Peng Du,Aobo Wang,Tianyi Wang,Fangda Si,Jian Li,Xiaochuan Kong 대한척추신경외과학회 2022 Neurospine Vol.19 No.3
Objective: Posterior apophyseal ring fracture (PARF) is an uncommon disorder that is usually accompanied by lumbar disc herniation (LDH). The aim of this study to describe the 8-year experience of performing minimally invasive treatment of PARF, giving particular attention to surgical technique and clinical outcome. Methods: We reviewed 1,324 consecutive patients with LDH seen in our department between 2013 and 2020. Forty-eight patients (3.63%) were enrolled who were diagnosed with PARF associated with LDH and underwent transforminal endoscopic lumbar discectomy (TELD). Mean duration of the final postoperative follow-up was 5.1 years. The control group was comprised of 50 patients diagnosed with LDH without PARF at the same facility. Data on clinical outcomes were analyzed. Results: The mean operation time in the PARF group was 105.4 minutes, which was longer than the mean operation time of the control group (83.9 minutes) (p = 0.001). Surgical complications, including dural tears (6.3%) and surgical instrument rupture (4.2%) were more common in the PARF group (p = 0.025). However, there was no significant difference in the proportion of excellent and good results and recurrence rates between the LDH patients with and those without PARF, respectively. Conclusion: TELD is a safe and effective minimally invasive approach for the treatment of PARF. However, minimally invasive techniques may require longer operation time and steeper learning curve for inexperienced surgeons. The separation and removal of bone fragments, a key step in the procedure, requires patience and care to prevent rupture, residual surgical instruments, and leakage of cerebrospinal fluid.