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 : Nanqing (검색결과 4 건)
- 무료
- 기관 내 무료
- 유료
-
Nonlinear Channel Estimation Based on Multi-level PN Sequences in OFDM Systems
Nanqing Zhou,Hao Liu 보안공학연구지원센터 2008 International Journal of Hybrid Information Techno Vol.1 No.2
Nonlinear distortion of power amplifier is one of the major factor that degrades the performance of OFDM systems .Instead of estimating the nonlinearity at transmitter such as ordinary pre-distortion (PD), this paper estimates the nonlinearity of amplifier at the receiver. The problem is that nonlinear and multipath dispersion mix together at receiver end. And their parameters are generally unknown, so conventional method doesn’t work well. In this paper, an algorithm that estimates both the nonlinear parameters of the power amplifier and the impulse response of the wireless channel is proposed. Multi-level PN sequences are transmitted to construct a Vandermonde matrix, which separates the nonlinearity and linearity into different subspaces. The separation makes it easy to estimate the nonlinearity and linearity independently.
-
On reflexive modules over commutative rings
Yuxian Geng,Nanqing Ding 대한수학회 2015 대한수학회보 Vol.52 No.1
Let $R$ be a commutative ring and $U$ an $R$-module. The aim of this paper is to study the duality between $U$-reflexive (pre)envelopes and $U$-reflexive (pre)covers of $R$-modules.
-
ON REFLEXIVE MODULES OVER COMMUTATIVE RINGS
Geng, Yuxian,Ding, Nanqing Korean Mathematical Society 2015 대한수학회보 Vol.52 No.1
Let R be a commutative ring and U an R-module. The aim of this paper is to study the duality between U-reflexive (pre)envelopes and U-reflexive (pre)covers of R-modules.
-
Liu Qian,Du Bin,Qi Wei,Mai Yuxiang,Zhao Yushun,Chen Nanqing 대한금속·재료학회 2022 ELECTRONIC MATERIALS LETTERS Vol.18 No.5
Development of electric branches caused by partial discharge leads to degradation in the performance of epoxy resin insulation materials, which seriously threatens the safe and stable operation of power equipment. In this study, n-tetradecanol (MA)@polystyrene microsphere (PS)@Fe3O4 core–shell phase change microcapsules were designed and prepared. Doping 0.1 wt% phase change microcapsular material into the epoxy resin cured compound inhibited the development of electric branches. SEM and EDS tests showed that the phase-change microcapsules had monodisperse spherical core–shell structures with an MA encapsulation rate of 24.73% and excellent phase-change thermal storage capacity. Electric field simulations revealed that Fe3O4 nanoparticles in the microcapsule shell enhanced the local field strength of the cured epoxy resin and induced the development of electric branches toward the interior of the microcapsule. Moreover, doping of microcapsules into the epoxy resin significantly slowed the rate of temperature rise and thus inhibited further development of electric branches in epoxy resin cured products. In comparison with the epoxy resin cured without microcapsules, it was found that the longitudinal and transverse lengths of electric branches were reduced by 56.6% and 69.1%, respectively, in the epoxy resin cured with 0.1 wt% MA@PS@Fe3O4 microcapsules, and the electric branch initiation field strength was increased from 0.57 to 0.68 kV/mm. This indicated that MA@PS@Fe3O4 microcapsules significantly improved the electrical branch resistance of epoxy resin cured products, and this provides a new approach for extensive applications of epoxy resin insulation materials and safe and stable operation of power equipment.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
