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Partial Doi-Hopf模的辫子Monoidal范畴 被引量:1
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作者 姜秀燕 贾玲 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2010年第2期241-244,共4页
通过引入Monoidal Partial Doi-Hopf数组和模的概念及例子,得到Partial Doi-Hopf模范畴是一个Monoidal范畴.在此基础上根据多种重要模范畴的辫子结构构造了此范畴的辫子,并得到了使Partial Doi-Hopf模范畴成为辫子Monoidal范畴的充要条件.
关键词 partial缠绕模 MONOIDAL范畴 辫子
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Making the category of entwined modules into a braided monoidal category
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作者 刘玲 王栓宏 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期250-252,共3页
The question of how the category of entwined modules can be made into a braided monoidal category is studied. First, the sufficient and necessary conditions making the category into a monoidal category are obtained by... The question of how the category of entwined modules can be made into a braided monoidal category is studied. First, the sufficient and necessary conditions making the category into a monoidal category are obtained by using the fact that if (A, C, ψ) is an entwining structure, then A × C can be made into an entwined module. The conditions are that the algebra and coalgebra in question are both bialgebras with some extra compatibility relations. Then given a monodial category of entwined modules, the braiding is constructed by means of a twisted convolution invertible map Q, and the conditions making the category form into a braided monoidal category are obtained similarly. Finally, the construction is applied to the category of Doi-Hopf modules and (α, β )-Yetter-Drinfeld modules as examples. 展开更多
关键词 doi-hopf module entwined module braided monoidal category
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Laser pulse modulation instabilities in partially stripped plasma 被引量:2
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作者 胡强林 刘世炳 蒋毅坚 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第12期2546-2551,共6页
The laser pulse modulation instabilities in partially stripped plasma were discussed based on the phase and group velocities of the laser pulse and the two processes that modulation instabilities excited. The excitati... The laser pulse modulation instabilities in partially stripped plasma were discussed based on the phase and group velocities of the laser pulse and the two processes that modulation instabilities excited. The excitation condition and growth rate of the modulation instability were obtained. It was found that the positive chirp and competition between normal and abnormal dispersions play important roles in the modulation instability. In the partially stripped plasma, the increased positive chirp enhances the modulation instability, and the dispersion competition reduces it. 展开更多
关键词 partially stripped plasma modulation instability photon acceleration
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Selective partial salivary glands sparing during intensity-modulated radiation therapy for nasopharyngeal carcinoma 被引量:1
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作者 Guangjin Yuan Qianwen Li +4 位作者 Shixian Chen Chengwei Zheng Jiang Tang Jiang Hu Ximing Xu 《Oncology and Translational Medicine》 2017年第2期65-70,共6页
Objective This study evaluated the dosimetric consequences of selective partial salivary gland sparing during intensity-modulated radiotherapy(IMRT) for patients with nasopharyngeal carcinoma(NPC).Methods Ten patients... Objective This study evaluated the dosimetric consequences of selective partial salivary gland sparing during intensity-modulated radiotherapy(IMRT) for patients with nasopharyngeal carcinoma(NPC).Methods Ten patients with NPC were enrolled in the study.Two IMRT plans were produced for each patient:conventional(control) and partial salivary glands-sparing(treatment),with dose constraints to the entire parotid glands or partial salivary glands(including the parotid and submandibular glands,delineated with the adjacent distance of at least 0.5 cm between the glands and PTV,the planning target volume) in planning,respectively.Dosimetric parameters were compared between the two plans,including the V_(110%),V_(100%),V_(95%)(the volume covered by more than 110%,100%,or 95% of the prescribed dose),Dmin(the minimum dose) of PTV,homogeneity index(HI),conformity index(CI),and the mean dose and percentage of the volume receiving 30 Gy or more(V_(30)) for the parotid glands and submandibular glands.Results Treatment plans had significantly lower mean doses and V_(30) to both the entire parotid glands and partial parotid glands than those in control plans.The mean doses to the partial submandibular glands were also significantly lower in treatment plans than in control plans.The PTV coverage was comparable between the two plans,as indicated by V_(100%),V_(95%),Dmin,CI,and HI.The doses to critical structures,including brainstem and spinal cord,were slightly but not significantly higher in treatment plans than in control plans.Conclusion A selective partial salivary gland-sparing approach reduces the doses to parotid and submandibular glands during IMRT,which may decrease the risk of post-radiation xerostomia while not compromising target dose coverage in patients with NPC. 展开更多
关键词 NASOPHARYNGEAL carcinoma INTENSITY-modulATED RADIOTHERAPY SELECTIVE partial salivarygland sparing
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Improved partial response maximum likelihood method combining modulation code for signal waveform modulation multi-level disc
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作者 王鹤群 裴京 潘龙法 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期213-219,共7页
In this paper, we describe an improved adaptive partial response maximum likelihood (PRML) method combining modulation code tbr signal waveform modulation multi-level disc. This improved adaptive PRML method employs... In this paper, we describe an improved adaptive partial response maximum likelihood (PRML) method combining modulation code tbr signal waveform modulation multi-level disc. This improved adaptive PRML method employs partial response equalizer and adaptive viterbi detector combining modulation code. Compared with the traditional adaptive PRML detector, the improved PRML detector additionally employs illogical sequence detector and corrector. Illogical sequence detector and corrector can aw)id the appearance of illogical sequences effectively, which do not follow the law of modulation code for signal waveform modulation multi-level disc, and obtain the correct sequences. We implement the improved PRML detector using a DSP and an FPGA chip. The experimental results show good performance. The higher efficient and lower complexity can be obtained by using the improved PRML method than by using the previous PRML method. Meanwhile, resource utilization of the improved PRML detector is not changed, but the bit error rate (BER) is reduced by more than 20%. 展开更多
关键词 multi-level disc signal waveform modulation viterbi detector partial response maximum likeli-hood
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群partial缠绕结构 被引量:2
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作者 贾玲 姜秀燕 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2011年第3期253-255,共3页
首先引入了群partial缠绕结构和群partial缠绕模,并给出例子和性质.最后构造了从群partial缠绕模范畴到模范畴的忘却函子.
关键词 partial缠绕结构 partial缠绕模 忘却函子
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偏Doi-Hopf模的Maschke型定理 被引量:1
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作者 姜秀燕 王志忠 +1 位作者 金天坤 李秀丽 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2011年第2期259-262,共4页
通过引入偏Doi-Hopf模积分映射的概念,证明了经典表示理论中的Maschke型定理在偏Doi-Hopf模条件下仍成立,即如果(H,A,C)是带有正规积分映射的偏Doi-Hopf数据,映射f:M→N是偏Doi-Hopf模同态,则只要f作为右A-模映射存在截面映射(收缩映射)... 通过引入偏Doi-Hopf模积分映射的概念,证明了经典表示理论中的Maschke型定理在偏Doi-Hopf模条件下仍成立,即如果(H,A,C)是带有正规积分映射的偏Doi-Hopf数据,映射f:M→N是偏Doi-Hopf模同态,则只要f作为右A-模映射存在截面映射(收缩映射),则f作为偏Doi-Hopf模映射也存在截面映射(收缩映射). 展开更多
关键词 doi-hopf MASCHKE型定理 H-余模代数
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偏Doi-Hopf群结构
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作者 姜秀燕 李颖 +1 位作者 赵国传 孙凤芝 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2011年第6期989-992,共4页
通过引入偏Doi-Hopf群结构和偏Doi-Hopf群模的概念,推广了Doi-Hopf结构,并给出其应用实例和基本的代数性质.综合群余代数和偏缠绕结构的思想构造了从偏Doi-Hopf群模范畴到模范畴的忘却函子,并证明了它有右伴随函子.
关键词 doi-hopf群结构 偏Doi—Hopf群模 忘却函子
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Partial缠绕模的辫子monoidal范畴
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作者 贾玲 史美华 《西北师范大学学报(自然科学版)》 CAS 北大核心 2016年第3期6-9,共4页
给出了使partial缠绕模范畴成为辫子monoidal范畴的充要条件.
关键词 partial缠绕模 辫子 MONOIDAL范畴
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Partial H-Hopf群模范畴
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作者 陈笑缘 史美华 《浙江大学学报(理学版)》 CAS CSCD 2012年第6期619-622,共4页
首先引入Partial H-Hopf群数组和Partial H-Hopf群模的定义,然后给出相关例子,最后证明了从PartialH-Hopf群模范畴到模范畴的忘却函子有伴随函子.
关键词 partial HOPF群余代数 partial H-Hopf群模 群余代数 半Hopf群余代数
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偏Doi-Hopf π-模上Rafael定理的应用
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作者 郭双建 王圣祥 《数学进展》 CSCD 北大核心 2016年第5期652-664,共13页
设α∈π(π是一个群),本文讨论了忘却函子F^((α)):M_A^(π-C)→M_A_α的可分性,并得到函子F^((α))可分的充要条件.作为结果的应用,证明了偏Doi-Hopfπ-模的Maschke型定理.
关键词 HOPF Π-余代数 MASCHKE型定理 doi-hopfπ-模
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偏Doi-Hopf π-模范畴和函子(英文)
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作者 王圣祥 董丽红 《南京大学学报(数学半年刊)》 CAS 2013年第1期56-66,共11页
设π-是一个群.本文我们引入了Hopf π-代数上的模的Doi-Hopf π-概念.得到了偏Doi-Hopf π-模范畴上的忘却函子可分的充要条件,其中忘却函子忘却的是π-A作用.作为应用,我们证明了偏Doi-Hopf π-模范畴上的Maschke型定理.
关键词 Hopfπ-代数 doi-hopfπ-模 余积分 MASCHKE型定理
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Partial crossed模
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作者 张颖颖 贾玲 《浙江大学学报(理学版)》 CAS CSCD 2012年第4期374-376,共3页
首先引入了partial crossed模的概念并给出例子,证明了实际上它是一种特殊的partial Doi-Hopf模.
关键词 partial crossed模 partial doi-hopf HOPF代数
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High-voltage super-junction lateral double-diffused metal-oxide semiconductor with a partial lightly doped pillar 被引量:3
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作者 伍伟 张波 +2 位作者 方健 罗小蓉 李肇基 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期633-636,共4页
A novel super-junction lateral double-diffused metal-oxide semiconductor (SJ-LDMOS) with a partial lightly doped P pillar (PD) is proposed. Firstly, the reduction in the partial P pillar charges ensures the charge... A novel super-junction lateral double-diffused metal-oxide semiconductor (SJ-LDMOS) with a partial lightly doped P pillar (PD) is proposed. Firstly, the reduction in the partial P pillar charges ensures the charge balance and suppresses the substrate-assisted depletion effect. Secondly, the new electric field peak produced by the P/P junction modulates the surface electric field distribution. Both of these result in a high breakdown voltage (BV). In addition, due to the same conduction paths, the specific on-resistance (Ron,sp) of the PD SJ-LDMOS is approximately identical to the conventional SJ-LDMOS. Simulation results indicate that the average value of the surface lateral electric field of the PD SJ-LDMOS reaches 20 V/μm at a 15 μm drift length, resulting in a BV of 300 V. 展开更多
关键词 super-junction lateral double-diffused metal-oxide semiconductor partial lightly doped pillar electric field modulation breakdown voltage
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Feasibility of the partial-single arc technique in RapidArc planning for prostate cancer treatment 被引量:1
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作者 Suresh Rana ChihYao Cheng 《Chinese Journal of Cancer》 SCIE CAS CSCD 2013年第10期546-552,共7页
The volumetric modulated arc therapy(VMAT)technique,in the form of RapidArc,is widely used to treat prostate cancer.The full-single arc(f-SA)technique in RapidArc planning for prostate cancer treatment provides effici... The volumetric modulated arc therapy(VMAT)technique,in the form of RapidArc,is widely used to treat prostate cancer.The full-single arc(f-SA)technique in RapidArc planning for prostate cancer treatment provides efficient treatment,but it also delivers a higher radiation dose to the rectum.This study aimed to compare the dosimetric results from the new partial-single arc(p-SA)technique with those from the f-SA technique in RapidArc planning for prostate cancer treatment.In this study,10 patients with lowrisk prostate cancer were selected.For each patient,two sets of RapidArc plans(f-SA and p-SA)were created in the Eclipse treatment planning system.The f-SA plan was created using one full arc,and the p-SA plan was created using planning parameters identical to those of the f-SA plan but with anterior and posterior avoidance sectors.Various dosimetric parameters of the f-SA and p-SA plans were evaluated and compared for the same target coverage and identical plan optimization parameters.The f-SA and p-SA plans showed an average difference of±1%for the doses to the planning target volume(PTV),and there were no clear differences in dose homogeneity or plan conformity.In comparison to the f-SA technique,the p-SA technique reduced the doses to the rectum by approximately 6.1%to 21.2%,to the bladder by approximately 10.3%to 29.5%,and to the penile bulb by approximately 2.2%.In contrast,the dose to the femoral heads,the integral dose,and the number of monitor units were higher in the p-SA plans by approximately 34.4%,7.7%,and 9.2%,respectively.In conclusion,it is feasible to use the p-SA technique for RapidArc planning for prostate cancer treatment.For the same PTV coverage and identical plan optimization parameters,the p-SA technique is better in sparing the rectum and bladder without compromising plan conformity or target homogeneity when compared to the f-SA technique. 展开更多
关键词 治疗计划系统 SA技术 前列腺癌 ECLIPSE 辐射剂量 参数规划 优化参数 剂量分布
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The Cohomology Structures of Partial Entwining Structures
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作者 JIA Ling 《Chinese Quarterly Journal of Mathematics》 2019年第1期66-74,共9页
In this paper we mainly reveal the rich cohomology theories for partial entwining structures.
关键词 partial entwining STRUCTURE partial entwined module COHOMOLOGY
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Read channel for signal waveform modulation multi-level disc
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作者 王鹤群 徐海峥 +1 位作者 潘龙法 刘海龙 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期334-338,共5页
A novel read channel for signal waveform modulation multi-level disc is presented in this paper. This read channel employs timing recovery system and partial response maximum likelihood detector. Compared to the previ... A novel read channel for signal waveform modulation multi-level disc is presented in this paper. This read channel employs timing recovery system and partial response maximum likelihood detector. Compared to the previous read channel composed of level detection and run-length detection, the present read channel shows superiority in capacity increase and robust performance. Especially, relying on the partial response maximum likelihood detection, lower bit error rate can be obtained. 展开更多
关键词 multi-level disc signal waveform modulation read channel partial response maximum likelihood
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Binary-Sequence Frequency Hopping Communication Method Based on Pseudo-Random Linear Frequency Modulation
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作者 TANG Zhiqiang QUAN Houde +1 位作者 SUN Huixian CUI Peizhang 《Journal of Shanghai Jiaotong university(Science)》 EI 2021年第4期534-542,共9页
To improve the signal detection performance of binary-sequence frequency hopping communication when the complementary channel is jammed, a binary-sequence frequency hopping communication system based on pseudo-random ... To improve the signal detection performance of binary-sequence frequency hopping communication when the complementary channel is jammed, a binary-sequence frequency hopping communication system based on pseudo-random liner frequency modulation (LFM) is proposed. The transmitting end uses the chirp signal to carry out the in-band spread spectrum of the binary-sequence frequency hopping signal, and then sends it out through the radio frequency front end. At the receiving end, the received signal is dehopped and processed by fractional Fourier transform. The source information is obtained by sampling decision. Firstly, a binary-sequence frequency hopping system model based on pseudo-random LFM is constructed. Secondly, the bit error rate expression of anti-partial band jamming and follower jamming under the Rice channel is derived. The results show that this method has at least 5 dB performance gain than binary sequence frequency hopping for different parameter settings under partial band jamming and follower jamming, and the anti-jamming performance is significantly better than the conventional frequency hopping communication. 展开更多
关键词 binary-sequence frequency hopping liner frequency modulation(LFM) fractional fourier transform partial band jamming follower jamming
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超紧凑封装高压串联SiC MOSFET脉冲功率模块
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作者 姚陈果 张鹏浩 +4 位作者 余亮 付作鸿 颜薪瞩 雷智程 董守龙 《高电压技术》 北大核心 2025年第11期5683-5695,共13页
传统封装的高寄生电感限制了SiC MOSFET串联开关的开启速度。为此设计了一种面向芯片级高压串联SiC MOSFET模块的π形超紧凑封装,可将16级/20 kV的串联开关寄生电感削减至55.8 nH。首先,研究了超紧凑封装结构参数对回路寄生电感和电场... 传统封装的高寄生电感限制了SiC MOSFET串联开关的开启速度。为此设计了一种面向芯片级高压串联SiC MOSFET模块的π形超紧凑封装,可将16级/20 kV的串联开关寄生电感削减至55.8 nH。首先,研究了超紧凑封装结构参数对回路寄生电感和电场分布的影响。结果表明,板间距的减少能够显著降低寄生电感,然而其缩小受到绝缘可靠性的阻碍。为解决超紧凑封装绝缘问题以实现寄生电感极限削减,分别提出了相应的局放探测和绝缘增强方法。包含一种基于共模电荷测量的局放监测方法,用于脉冲电应力下局部放电起始电压(partial discharge inception voltage,PDIV)的准确测量。随后,通过六方氮化硼填料改性与复合提高了硅胶灌封料的绝缘,PDIV测量结果显示其满足了较小板间距封装的绝缘需求,从而实现了寄生电感的极限削减。此外,为了将超紧凑封装串联模块应用于脉冲发生,提出了一种分单元磁隔离-电容自触发混合驱动方案,在保障驱动隔离耐压能力的同时,提升了多级MOSFET的开启同步性和速度,实现了16级MOS模块在26 ns内的同步开通。相比传统TO-247串联,基于超紧凑封装串联开关的脉冲功率模块的开启速度提升显著。同时,模块运行中也展现出了充足的热管理能力。 展开更多
关键词 SiC MOSFET串联 功率模块封装 局部放电 隔离驱动 脉冲功率
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基于光谱的SF_(6)分解物中SO_(2)浓度检测仪设计
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作者 刘伟 毛逸凡 +1 位作者 霍思佳 杨帅 《应用光学》 北大核心 2025年第3期589-595,共7页
针对电气设备内六氟化硫(SF_(6))分解物中二氧化硫(SO_(2))浓度检测问题,对紫外吸收光谱分析模块设计和数据处理方法进行了研究。采用低功耗脉冲氙灯光源缩短预热时间,设计了多次反射的长光程气体吸收池,有效缩短响应时间;光源和微型光... 针对电气设备内六氟化硫(SF_(6))分解物中二氧化硫(SO_(2))浓度检测问题,对紫外吸收光谱分析模块设计和数据处理方法进行了研究。采用低功耗脉冲氙灯光源缩短预热时间,设计了多次反射的长光程气体吸收池,有效缩短响应时间;光源和微型光谱仪与气室直接耦合,减少用气量,稳定性更好。在280 nm~320 nm谱段进行SO_(2)浓度反演,采用偏最小二乘回归多元校正方法对SO_(2)谱段差分吸光度与SO_(2)浓度建立回归模型,模型误差小于0.5μL/L。设计了检测仪原理样机,试验验证了设计方案的可行性。 展开更多
关键词 紫外吸收光谱法 气体分析模块 二氧化硫浓度 偏最小二乘回归
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