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仙人掌图和卡氏积图的连通包数
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作者 贾倩琼 陈春霖 +1 位作者 秦文文 马儇龙 《井冈山大学学报(自然科学版)》 2024年第4期1-6,共6页
测地线的概念起源于几何学、拓扑学及函数分析中的凸集理论,它在选址问题、网络设计及控制理论等方面有重要意义。在图论中定义了凸性后,测地线问题及与之相关的测地数问题成为揭示图的结构性质的一个重要指标及参数。图的连通包数是定... 测地线的概念起源于几何学、拓扑学及函数分析中的凸集理论,它在选址问题、网络设计及控制理论等方面有重要意义。在图论中定义了凸性后,测地线问题及与之相关的测地数问题成为揭示图的结构性质的一个重要指标及参数。图的连通包数是定义在图中测地线上的一个参数。针对计算图的连通包数问题,本研究用组合分析法确定了仙人掌图C_(n)·C_(n)及卡氏积图P_(m)×K_(2)、P_(m)×C_(3)、P_(2)×C_(n)的连通包数,其中m≥2,n≥3,P_(m)是长度为m-1的路,C_(n)是长度为n的圈。 展开更多
关键词 凸集 连通包集 连通包数 仙人掌图 卡氏积
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一些简单有限连通图的连通包数 被引量:2
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作者 马儇龙 金剑行 钟国 《黄冈师范学院学报》 2013年第3期14-18,共5页
通过图的连通包集和连通包数的定义,得到了6类常见连通图(路、圈、树、完全二部图、轮图、蛛网图)的连通包数,并确定了Petersen图的连通包数。
关键词 连通图 包集 包数 连通包集 连通包数
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有关连通图的连通包数的一些结果 被引量:2
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作者 金剑行 邓天炎 马儇龙 《广西师范学院学报(自然科学版)》 2013年第1期4-8,共5页
通过图的连通包集和连通包数的定义,确定了测地数、包数和连通包数三者之间的大小关系,并通过一些特殊图(完全二部图、分裂图)构造了连通包数为3的3类图.
关键词 连通图 包集 包数 连通包集 连通包数
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蛛网图的连通包数(英文) 被引量:2
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作者 郭梦夏 邓天炎 +1 位作者 金剑行 惠志昊 《广西师范学院学报(自然科学版)》 2013年第4期28-31,共4页
证明了蛛网图W(m,n)的连通包数为hc(W(m,n))=m+2n-1.通过对蛛网图进行简化处理,即将蛛网图W(m,n)的叶子顶点去掉,得到图G的连通包数为hc(G)=n2?+m.
关键词 测地线 连通包数 蛛网图
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几类图的连通包数 被引量:1
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作者 王展鹏 贾倩琼 马儇龙 《井冈山大学学报(自然科学版)》 2023年第5期6-10,14,共6页
通过研究几类图的连通包数,确定了友谊图、风车图及联图P_(m)∨K_(n)^(-)与C_(m)∨K_(n)^(-)的连通包数,其中P_(m)是具有m个顶点的路,C_(m)是长度为m的圈,且k_(n)^(-)是完全图K_(n)的补图。
关键词 凸集 连通包集 连通包数
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无尺度网络的数据包传输元胞自动机模型研究 被引量:1
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作者 唐红 廖荣南 胡容 《计算机应用研究》 CSCD 北大核心 2010年第12期4686-4689,共4页
为了更真实地模拟网络行为,提出了一种基于无尺度网络的数据包传输元胞自动机模型,模型中通过增加缓存队列大小和提高中心节点的处理速度来减少丢包数,提高网络性能。仿真结果表明,在元胞交互规则的作用下,数据包发送速率,缓存队列大小... 为了更真实地模拟网络行为,提出了一种基于无尺度网络的数据包传输元胞自动机模型,模型中通过增加缓存队列大小和提高中心节点的处理速度来减少丢包数,提高网络性能。仿真结果表明,在元胞交互规则的作用下,数据包发送速率,缓存队列大小和丢包数在时间序列上都具有自相似特性,自相似程度呈现负相关;它们在时间序列上是长程相关的,在功率谱图中都具有幂律分布特性,在高频段呈现出白噪声特性。 展开更多
关键词 无尺度网络 元胞自动机 包数 自相似性 功率谱 幂律特性
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Spatial and Temporal Characteristics of Agricultural Resource Utilization Efficiency in Gansu Province,China,Based on DEA
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作者 LIU Xiaoyu LIU Xuelu +2 位作者 Samuel ADINGO YU Jieru LI Xiaodan 《Journal of Resources and Ecology》 CSCD 2024年第6期1461-1475,共15页
This study takes the agricultural resource utilization efficiency of Gansu Province and its cities(prefectures)during 2008-2017 as the research object,evaluates the efficiency by using data envelopment analysis(DEA),m... This study takes the agricultural resource utilization efficiency of Gansu Province and its cities(prefectures)during 2008-2017 as the research object,evaluates the efficiency by using data envelopment analysis(DEA),mathematical statistics and literature research methods,selects 10 input indicators and 3 output indicators of agricultural production,and then calculates the comprehensive efficiency,technical efficiency and scale efficiency ofagricultural resources utilization in Gansu from 2008 to 2017,the redundancy of the input was analyzed by combining with the redundancy value,and projection analysis was applied to improve the input and allocation of agricultural resources.For the temporal characteristics of agricultural resource utilization efficiency in Gansu,the results show that the utilization efficiency is relatively low and fluctuates over time while gradually stabilizing,the comprehensive efficiency increased from 0.857 to 1,with values that were not 1 in 2008,2009,2010,2011,2012 and 2015,showing a relatively ineffective utilization state,and the utilization efficiency had a hysteresis effecton the implementation of policies.Meanwhile,the spatial distribution characteristics indicate large regional differences in utilization efficiency among the cities and prefectures,all of the cities can be divided into four categoriesaccording to their different comprehensive efficiency levels:the best(1.00),the second best(0.98-1.00),the lower(0.90-0.98)and the lowest(<0.90),and the corresponding characteristic agricultural development regions weredivided based on their actual situations;the redundancy of agricultural input factors still exists,especially in ecological factors such as climatic resources,agricultural fertilizer usage and agriculture practitioners;while the technical efficiency had obvious restrictions on the comprehensive efficiency.In summary,the input-output efficiency ofagricultural resources in Gansu is relatively low overall,the unbalanced regional development of utilization efficiency is obvious,and agricultural development is greatly constrained by ecological and technical factors.Therefore,the key to improving this situation lies in the integration of agricultural support funds to develop agricultural facility construction,adjust the agricultural input and industrial structure,actively promote the application of science andtechnology,vigorously develop regional characteristic agriculture,and create ecological and civilization agriculture. 展开更多
关键词 agricultural resources utilization efficiency data envelopment analysis temporal characteristics spatial distribution characteristics Gansu Province
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如何判别入侵检测系统性能
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作者 牟春华 《华南金融电脑》 2005年第8期51-53,共3页
随着互联网应用规模的不断拓大,网络安全问题也越来越受到人们的重视,网络安全产品的性能指标是每个用户采购安全产品时必须关注的问题,如果不知道这些指标的真实含义和测试标准,就容易被表面的参数所蒙蔽,做出错误的决策.
关键词 互联网 网络安全 入侵检测系统 数据流量 包数
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MDCE路由算法的分析与改进 被引量:1
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作者 杨万鑫 汪学明 夏红红 《计算机应用与软件》 北大核心 2021年第1期105-110,共6页
延迟容忍网络中基于位置的地理路由算法使用节点自我采集的GPS信息进行下一跳中继结点的选择,而节点的移动性会导致节点的实际位置在时刻改变,相对位置节点的移动方向信息比地理位置信息具有更好的稳定性。文献[1]提出的MDCE路由算法网... 延迟容忍网络中基于位置的地理路由算法使用节点自我采集的GPS信息进行下一跳中继结点的选择,而节点的移动性会导致节点的实际位置在时刻改变,相对位置节点的移动方向信息比地理位置信息具有更好的稳定性。文献[1]提出的MDCE路由算法网络负载率和丢包率很高,且由于DTN网络的特殊性,难以拥有多个相邻节点。对MDCE路由算法进行分析与改进,降低中继节点数、规避消息副本向来的方向传输。仿真结果表明,改进后的MDCE路由算法的网络负载率和丢包率明显降低,实用性更强。 展开更多
关键词 DTN MDCE 负载率 包数 资源受限
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Customized Optimization for Vehicle Acoustic Statistical Energy Analysis
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作者 Huang Yi Feng Qiuhan +3 位作者 Liu Jingqi Li Xueliang Liu Lin Yang Shaobo 《汽车文摘》 2024年第11期1-10,共10页
Statistical Energy Analysis(SEA) is one of the conventional tools for predicting vehicle high-frequency acoustic responses.This study proposes a new method that can provide customized optimization solutions to meet NV... Statistical Energy Analysis(SEA) is one of the conventional tools for predicting vehicle high-frequency acoustic responses.This study proposes a new method that can provide customized optimization solutions to meet NVH targets based on the specific needs of different project teams during the initial project stages.This approach innovatively integrates dynamic optimization,Radial Basis Function(RBF),and Fuzzy Design Variables Genetic Algorithm(FDVGA) into the optimization process of Statistical Energy Analysis(SEA),and also takes vehicle sheet metal into account in the optimization of sound packages.In the implementation process,a correlation model is established through Python scripts to link material density with acoustic parameters,weight,and cost.By combining Optimus and VaOne software,an optimization design workflow is constructed and the optimization design process is successfully executed.Under various constraints related to acoustic performance,weight and cost,a globally optimal design is achieved.This technology has been effectively applied in the field of Battery Electric Vehicle(BEV). 展开更多
关键词 Statistical Energy Analysis(SEA) Dynamic optimization Radial Basis Function(RBF) Vehicle sheet metal Sound package Battery Electric Vehicle(BEV)
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Preparation and Physicochemical Characterization of Quercetin-HP-β-CD Inclusion Complexes 被引量:3
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作者 杨照罡 古丽斯坦.阿吾提 +6 位作者 曹轶 朱静 伍博深 王坚成 吕万良 张烜 张强 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第2期69-75,共7页
Aim To prepare and characterize the QURC-HP-β-CD inclusion complexes and investigate the thermodynamic parameters of the process. Methods QURC-HP-β-CD inclusion complexes were prepared by the grinding method. The eq... Aim To prepare and characterize the QURC-HP-β-CD inclusion complexes and investigate the thermodynamic parameters of the process. Methods QURC-HP-β-CD inclusion complexes were prepared by the grinding method. The equilibrium inclusion constants and thermodynamic parameters were determinated by phase solubility analysis. Dissolution tests were performed to study the dissolution rate of inclusion complexes. The formation of inclusion complexes was confirmed by differential scanning calorimetry ( DSC), infrared spectroscopy (IR) , powder X-ray diffractometry (PXRD) and scanning electron microscopy (SEM). Results The aqueous solubility of quercetin was greatly increased ( about 37 folds) by inclusion technique, and the initial dissolution rate was markedly improved (10 folds) in the first 5 min. The results of DSC and SEM photographs showed that quercetin crystal disappeared in inclusion complexes, which indicated the formation of new phase. FT-IR spectra showed that the carbonyl quercetin crystal grinding method. absorption band of quercetin was shifted. PXRD showed that the diffraction peak of disappeared. Conclusion QURC-HP-β-CD inclusion complexes are produced by the The solubility of quercetin is improved by the inclusion technique. 展开更多
关键词 QUERCETIN HYDROXYPROPYL-Β-CYCLODEXTRIN inclusion complex inclusion constant Phase behavior
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Numerical simulation and physical analysis for dynamic behaviors of P/M TiAl alloy in hot-packed forging process 被引量:2
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作者 张伟 刘咏 +1 位作者 王丽 刘彬 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期901-906,共6页
The hot forging of large-scale P/M TiAl alloy billet deformation was investigated based on a joint application of Deform-3D-based numerical simulation and physical simulation techniques.The temperature dependence on t... The hot forging of large-scale P/M TiAl alloy billet deformation was investigated based on a joint application of Deform-3D-based numerical simulation and physical simulation techniques.The temperature dependence on the thermal and mechanical properties of the billet was considered and the optimum hot working temperature of packed TiAl alloy was 1150-1200 °C.Based on the simulation,the material flow and thermo mechanical field variables,such as stress,strain,and temperature distribution were obtained and the relationships of load—displacement and load—time were figured out.To verify the validity of the simulation results,the experiments were also carried out in a forging plant,and a pancake with diameter of 150 mm was obtained exhibiting a regular shape. 展开更多
关键词 TIAL hot packed forging numerical simulation physical simulation
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Measuring technical efficiency of Chinese nonferrous metals enterprises on a background of industry consolidation 被引量:5
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作者 危平 唐慧泉 +1 位作者 陈瑶 陈晓红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2797-2806,共10页
Since 2009, Chinese nonferrous metals industry has been carried out industry consolidation with strong support by the central government. This work examined technical efficiency of Chinese nonferrous metals firms and ... Since 2009, Chinese nonferrous metals industry has been carried out industry consolidation with strong support by the central government. This work examined technical efficiency of Chinese nonferrous metals firms and its change during the period of 2007 and 2011. Based on financial data from nonferrous metals listed companies, technical efficiency of nonferrous metal minerals mining firms and nonferrous metal smelting, pressing and processing firms was estimated respectively using the data envelopment analysis (DEA) method. It was found that, in both sectors, number of pure technical and scale inefficient firms dominated over efficient ones. Overall, their technical and scale efficiency tended to be very low after 2009. In particular, efficiency scores of nonferrous metal smelting, pressing and processing firms fluctuated greatly during the research period. And a limited number of large leading firms were able to maintain 100% efficiency score in the industry, while efficiency of most of other leading firms has declined since 2009. 展开更多
关键词 industry consolidation nonferrous metals finns data envelopment analysis (DEA) technical efficiency scale efficiency CONGLOMERATE
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Radar Target Discrimination based on waveletPackets for Reduced data Storage
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作者 唐白玉 沈海戈 +1 位作者 姜文利 柯有安 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期280-286,共7页
In order to storage resource of a radar recognition system, schemes for reducing data storage and for correlation discrimination of radar based on wavelet packets were proposed Experiment results at various signal-t... In order to storage resource of a radar recognition system, schemes for reducing data storage and for correlation discrimination of radar based on wavelet packets were proposed Experiment results at various signal-to-noise ratios were given The given.ability of the reduced data method's validity are supported by experimental results. Using optimal basis can get higher successful recognition rate using rigid wavelet basis. 展开更多
关键词 radar Keywords:radar recognition radar target wavelet packets data compression
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Parallel algorithm of generating closure of RDFS source
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作者 苗壮 张亚非 +1 位作者 陆建江 宋自林 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期435-438,共4页
To decrease the time of generating a closure, a parallel algorithm of generating the closure of a resource description framework schema (RDFS) source is presented. In the algorithm, RDFS triples in the source are cl... To decrease the time of generating a closure, a parallel algorithm of generating the closure of a resource description framework schema (RDFS) source is presented. In the algorithm, RDFS triples in the source are classified according to the forms of triples in the entailment rules and it reduces the scope of searching for specific triples. The dependence among the classes of triples is analyzed. Based on the classification, the initial RDFS source is partitioned into several subsets. The subsets are distributed to each process, and the closure is generated in parallel by applying the RDFS entailment rules. Parallel generating the closure of an RDFS source takes less time and increases efficiency. 展开更多
关键词 parallel CLOSURE resource description framework (RDF) graph RDFS source
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Efficiency Valuation of DMUs with Undesirable Outputs 被引量:1
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作者 边馥萍 杨爱萍 《Transactions of Tianjin University》 EI CAS 2002年第4期295-298,共4页
The researching on the DMUs with undesirable outputs gives the non-radial model FDEA of the relative efficiency evaluation,proves the efficiency theories, and calculates the example.The application of FDEA model shows... The researching on the DMUs with undesirable outputs gives the non-radial model FDEA of the relative efficiency evaluation,proves the efficiency theories, and calculates the example.The application of FDEA model shows its importance in the production to save the resources,improve the desirable outputs, and decrease the undesirable outputs,especially reduce the environmental pollution. 展开更多
关键词 data envelopment analysis undesirable output FDEA model environmental pollution
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Research on Evaluation and Optimization of Regional Land Use Structure Efficiency 被引量:1
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作者 张群 《Agricultural Science & Technology》 CAS 2016年第7期1749-1752,共4页
[Objective] The purpose of this study is to judge the rationality of land use structure from new perspectives and method. [Method] The theory of data en- velopment analysis (DEA) has been employed in this article. A... [Objective] The purpose of this study is to judge the rationality of land use structure from new perspectives and method. [Method] The theory of data en- velopment analysis (DEA) has been employed in this article. A case study of evalu- ation of land use structure for Wujin district in 2012 is provided to illustrate the ap- plication of this research model. At the micro perspective, land use efficiency has been analyzed by use of data envelopment analysis model. The optimization and adjustment direction in land use structure has been pointed out from the view point of land use efficiency. [Result] The result has shown that the research method based on information entropy and data envelopment analysis model can effectively overcome the drawback of traditional evaluation techniques. Compared with the tra- ditional methods, the new optimization model based on a structure of the multi-crite- ria factors and objective weighting method can evaluate the rationality of land use structure more comprehensively. 展开更多
关键词 Evaluation for efficiency Land use structure Data Envelopment Analysis
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Enveloping algebras of generalized H-Hom-Lie algebras
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作者 王圣祥 王栓宏 《Journal of Southeast University(English Edition)》 EI CAS 2015年第4期588-590,共3页
Let H be a Hopf algebra and HYD the Yetter- Drinfeld category over H. First, the enveloping algebra of generalized H-Hom-Lie algebra L, i.e., Hom-Lie algebra L H in the category HYD, is constructed. Secondly, it is o... Let H be a Hopf algebra and HYD the Yetter- Drinfeld category over H. First, the enveloping algebra of generalized H-Hom-Lie algebra L, i.e., Hom-Lie algebra L H in the category HYD, is constructed. Secondly, it is obtained that U(L) = T( L)/L where I is the Hom-ideal of T(L) generated by {ll'-l_((-1))·l'l_0-[l,l']|l,l'∈L}, and u: L,T(L)/I is the canonical map. Finally, as the applications of the result, the enveloping algebras of generalized H-Lie algebras, i.e., the Lie algebras in the category MyDn and the Hom-Lie algebras in the category of left H-comodules are presented, respectively. 展开更多
关键词 enveloping algebra generalized H-Hom-Li^algebra Yetter-Drinfeld category
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Injective Envelopes of a Hilbert C~*Module
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作者 许天周 蔡涛 李炳照 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期119-124,共6页
As in homology, the notion of injectivity is introduced in the category whose objects are Hilbert C * module over a C * algebra and whose morphism are bounded module operators. The definition of injective envelope... As in homology, the notion of injectivity is introduced in the category whose objects are Hilbert C * module over a C * algebra and whose morphism are bounded module operators. The definition of injective envelopes of an extension of a Hilbert C * modules over a C * algebra is introduced, and is characterized in terms of the injectivity and essence. It is shown that every Hilbert C * module has a unique (up to H isometrics) injective envelope if it exists. It is also shown that an extension of a Hilbert C * module is an injective envelope if and only if it is an injective and essential extension. Moreover, every Hilbert C * module over a W * algebra has a unique (up to H isometrics) injective envelope and the injective envelope of a Hilbert C * module H is maximal essential extension of H . 展开更多
关键词 C * algebra Hilbert C * module injective envelope
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NUMERICAL SIMULATION OF DIODE-PUMPED DOUBLE-CLAD Tm-Ho DOPED FLUORIDE LASERS
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作者 王家新 庞冬青 +2 位作者 张宇生 AhmadM KingTA 《Transactions of Tianjin University》 EI CAS 1997年第2期3-8,共6页
Numerical simulation is described which estimates the performance of thulium sensitized holmium doped CW fluoride fiber laser at 2.04 μm for both core and cladding pumped. This model takes into account the mechanis... Numerical simulation is described which estimates the performance of thulium sensitized holmium doped CW fluoride fiber laser at 2.04 μm for both core and cladding pumped. This model takes into account the mechanisms of cross relaxation and energy transfer to describe the laser operation. A subroutine program for calculating the absorption rate of cladding pumped scheme is included in the model. The losses of signal and pump light along the fiber have been taken into account. The test of cladding pumped scheme program shows good agreement with the experimental result. The experimental results of core pumping Tm Ho doped fiber laser in fluoride host are compared with the present model, and shows a good agreement with calculations. This model also provides data of the optimum parameters for the configuration of the efficient cladding pumped Tm Ho fluoride laser systems. 展开更多
关键词 numerical simulation cladding pumped Tm Ho co doped fiber laser
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