http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Hongzhou Li (검색결과 4 건)
- 무료
- 기관 내 무료
- 유료
-
Crashworthiness design of bionic-shell thin-walled tube under axial impact
Lingyun Qin,Shuyi Yang,Hongzhou Li,Juchuan Dai,Guosheng Wang,Qihui Ling,Zhewu Chen 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.7
Bionic structures have been widely utilized in the crashworthiness design of thin-walled structures due to their superior energy absorption capabilities. This study constructed a bionic-shell thin-walled tube (BST) with excellent crashworthiness based on the structural bionic principle using the shell shape cross-section as the prototype. First, the theoretical model of the mean crushing force (MCF) for BST under axial compression was developed. An experiment was conducted and the reliability of the finite element model was verified. Then, the effects of structural parameters, such as the number of ribs, wall thickness, and inner tube diameter on the crashworthiness of the BST were investigated using the finite element method. Finally, to obtain the ideal configuration of structural parameters, the BST was optimized using the response surface method (RSM) with specific energy absorption (SEA) and crushing force efficiency (CFE) as the optimization objectives and peak crushing force (PCF) as the constraint condition. The results showed that the BST with six ribs exhibited the best crashworthiness under the same mass. The optimized BST-6 was found to have better energy absorption performance than the double circular tube (DCT) and the bionic-horsetail thin-walled tube (BHT). Compared with the DCT, the SEA and CFE increased by 35.15 % and 32.23 %, respectively.
-
Parameter Sensitivity Analysis of a New Fabricated Rectangular Tunnel Joint Using Numerical Method
Zhen Huang,Chenlong Zhang,Shaokun Ma,Hai Zhang,Zhang Zhou,Hongzhou Li 대한토목학회 2022 KSCE Journal of Civil Engineering Vol.26 No.2
An assembled rectangular tunnel has the advantages of high space utilization rate and strong urban applicability. This solution has been widely used in urban underground traffic construction. During their construction and operation, the joints are the weakest parts of the structure. The mechanical behavior of joints is closely related to the safety of the tunnel; thus, it is important to use a joint with good mechanical behavior. This study presents a new type of joints for shallow buried assembled rectangular tunnels. To evaluate the effect of design parameters (tenon depth and tenon angle) on the behavior of joints, the finite element method was used. At the same time, the mechanical behavior of rectangular tunnel joint was analyzed and compared with that of a traditional straight joint under the same loading conditions, showing better results. The performance-based engineering (PBE) concept was implemented to evaluate the robustness of rectangular tunnel joints. The results show that if the bolt is placed on the tensile side of the structure, it provides a strong restraining effect on the deformation of the joint. When the tenon depth and angle are 0.8 m and 3.6°, respectively, the overall behavior of the rectangular tunnel joint was improved. The new type of assembled rectangular tunnel joint designed in this study has a good application prospect in a shallow stratum and provides new ideas for the design and construction of such tunnels.
-
Hong Zhou,Youping Li,Huifang Liu,Zhongyu Fan,Jie Xia,Shanli Chen,Yuxiang Zheng,Xiaocui Chen 대한환경공학회 2015 Environmental Engineering Research Vol.20 No.3
The PM10, SO₂ and NO₂ mass concentrations were obtained over five years from monitoring stations across Nanchong, a southwest city in China. Changes in urban air quality over time, as well as the factors influencing that change, were evaluated based on air pollutant concentrations, the Air Pollution Index (API), and the Comprehensive Pollution Index (P). The results showed that the total annual mean PM10, SO₂ and NO₂ concentrations over the five years studied were 61.1±1.1, 45.0±3.9 and 34.9±4.9 μg·m-3, respectively. The annual mean concentrations displayed a generally decreasing trend; lower than the annual mean second-level air quality limit. Meanwhile, the annual mean API values were in a small range of 52-53, the air quality levels were gradeⅡ, and P values were 1.06-1.21 less than the slight level (P ≤ 1.31). Total monthly mean PM10, SO₂, NO₂ concentrations, and API and P values were consistently higher in winter and spring than during autumn and summer. The results of a correlation analysis showed that temperature and pressure were the major meteorological factors influencing pollution levels. Pollution sources included industrial coal and straw burning, automobiles exhaust and road dust, fireworks, and dust storms.
-
Analysis and validation of novel inverter and LCC‑S topology‑based WPT system
Hong Zhou,Haitang Liu,Qijun Deng,Li Fang 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.3
Wireless power transfer (WPT) technology has been widely researched and employed due to its advantages when compared with conventional cable-connected power transmission in terms of convenience, flexibility, security, and so on. In common wireless power transfer systems, DC sources, such as batteries and AC–DC modules, are frequently utilized in the front end of the inverters to generate a relatively high frequency circuit driving voltage. The strategy of directly arranging inverters behind AC sources is feasible by replacing a single NMOS with a pair of back-to-back placed switches that can tolerate both forward and reverse voltage. This novel inverter structure is systematically explored from the perspectives of the time domain and the frequency domain, which demonstrates the convenience and feasibility of the proposed structure. Due to the canceling of the front-end rectifier, the complexity of the system hardware is significantly reduced. In addition, when taking the constant current output feature into account, the LCC-S topology is comprehensively investigated and properly applied. Finally, a laboratory platform is constructed and experiments are conducted to verify the effectiveness of the proposed structure. Furthermore, experiment results show that there is only a slight transfer efficiency decrease when compared with the commonly adopted scheme containing an extra diode rectifier at the transmitting side.
ScienceON
DBpia연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
