The function of the air target threat evaluation （TE） is the foundation for weapons allocation and senor resources management within the surface air defense. The multi-attribute evaluation methodology is utilized to...The function of the air target threat evaluation （TE） is the foundation for weapons allocation and senor resources management within the surface air defense. The multi-attribute evaluation methodology is utilized to address the issue of the TE in which the tactic features of the detected target are treated as evaluation attributes. Meanwhile, the intuitionistic fuzzy set （IFS） is employed to deal with information uncertainty in the TE process. Furthermore, on the basis of the entropy weight and inclusion-comparison probability, a hybrid TE method is developed. In order to accommodate the demands of naturalistic decision making, the proposed method allows air defense commanders to express their intuitive opinions besides incorporating into the threat features of the detected target. An illustrative example is provided to indicate the feasibility and advantage of the proposed method.展开更多
The pulse energy in the ultrafast soliton fiber laser oscillators is usually limited by the well-known wave-breaking phenomenon owing to the absence era desirable real saturable absorber （SA） with high power toleran...The pulse energy in the ultrafast soliton fiber laser oscillators is usually limited by the well-known wave-breaking phenomenon owing to the absence era desirable real saturable absorber （SA） with high power tolerance and large modulation depth. Here, we report a type of microfiber-based MoTe2 SA fabricated by the magnetron-sputtering deposition （MSD） method. High-energy wave-breaking free soliton pulses were generated with pulse duration/pulse energy/average output power of 229 fs/2.14 nJ/57 mW in the 1.5 μm regime and 1.3 ps/13.8 nJ/ 212 mW in the 2 μm regime, respectively. To our knowledge, the generated soliton pulses at 1.5μm had the shortest pulse duration and the highest output power among the reported erbium-doped fiber lasers mode locked by transition metal dichalcogenides. Moreover, this was the first demonstration of a MoTe2-based SA in fiber lasers in the 2 ltm regime, and the pulse energy/output power are the highest in the reported thulium-doped fiber lasers mode locked by two-dlmensional materials. Our results suggest that a microfiber-based MoTe2 SA could be used as an excellent photonic device for ultrafast pulse generation, and the MSD technique opens a promising route to produce a high-performance SA with high power tolerance and large modulation depth, which are beneficial for high-energy wave-breaking free pulse generation.展开更多
We reported diverse soliton operations in a thulium/holmium-doped fiber laser by taking advantage of a tapered fiber-based topological insulator（TI） Bi2Te3 saturable absorber（SA）.The SA had a nonsaturable loss of ...We reported diverse soliton operations in a thulium/holmium-doped fiber laser by taking advantage of a tapered fiber-based topological insulator（TI） Bi2Te3 saturable absorber（SA）.The SA had a nonsaturable loss of 53.5% and a modulation depth of 9.8%.Stable fundamentally mode-locked solitons at 1909.5 nm with distinct Kelly sidebands on the output spectrum,a pulse repetition rate of 21.5 MHz,and a measured pulse width of 1.26 ps were observed in the work.By increasing the pump power,both bunched solitons with soliton number up to 15 and harmonically mode-locked solitons with harmonic order up to 10 were obtained.To our knowledge,this is the first report of both bunched solitons and harmonically mode-locked solitons in a fiber laser at 2 μm region incorporated with TIs.展开更多
基金supported by the National Natural Science Foundation of China (70871117 70571086)the Development Foundation of Dalian Naval Academy
文摘The function of the air target threat evaluation （TE） is the foundation for weapons allocation and senor resources management within the surface air defense. The multi-attribute evaluation methodology is utilized to address the issue of the TE in which the tactic features of the detected target are treated as evaluation attributes. Meanwhile, the intuitionistic fuzzy set （IFS） is employed to deal with information uncertainty in the TE process. Furthermore, on the basis of the entropy weight and inclusion-comparison probability, a hybrid TE method is developed. In order to accommodate the demands of naturalistic decision making, the proposed method allows air defense commanders to express their intuitive opinions besides incorporating into the threat features of the detected target. An illustrative example is provided to indicate the feasibility and advantage of the proposed method.
基金National Natural Science Foundation of China(NSFC)(11704260,61405126,61605122,61775146)Shenzhen Science and Technology Project(JCY20150324141711695,JCYJ20160427105041864,JSGG20160429114438287,KQJSCX20160226194031,JCYJ20160422103744090)+1 种基金Beijing University of Posts and Telecommunications(BUPT)(IPOC2015B003)Natural Science Foundation of Guangdong Province(2016A030310049,2016A030310059)
文摘The pulse energy in the ultrafast soliton fiber laser oscillators is usually limited by the well-known wave-breaking phenomenon owing to the absence era desirable real saturable absorber （SA） with high power tolerance and large modulation depth. Here, we report a type of microfiber-based MoTe2 SA fabricated by the magnetron-sputtering deposition （MSD） method. High-energy wave-breaking free soliton pulses were generated with pulse duration/pulse energy/average output power of 229 fs/2.14 nJ/57 mW in the 1.5 μm regime and 1.3 ps/13.8 nJ/ 212 mW in the 2 μm regime, respectively. To our knowledge, the generated soliton pulses at 1.5μm had the shortest pulse duration and the highest output power among the reported erbium-doped fiber lasers mode locked by transition metal dichalcogenides. Moreover, this was the first demonstration of a MoTe2-based SA in fiber lasers in the 2 ltm regime, and the pulse energy/output power are the highest in the reported thulium-doped fiber lasers mode locked by two-dlmensional materials. Our results suggest that a microfiber-based MoTe2 SA could be used as an excellent photonic device for ultrafast pulse generation, and the MSD technique opens a promising route to produce a high-performance SA with high power tolerance and large modulation depth, which are beneficial for high-energy wave-breaking free pulse generation.
基金supported by the State Key Program of National Natural Science of China (Grant Nos.61235008,61405254,61340017,and 61435009)the Fundamental Researches Foundation of National University of Defense Technology (Grant No.GDJC13-04)the Hunan Provincial Natural Science Foundation of China (Grant No.14JJ3001)
文摘We reported diverse soliton operations in a thulium/holmium-doped fiber laser by taking advantage of a tapered fiber-based topological insulator（TI） Bi2Te3 saturable absorber（SA）.The SA had a nonsaturable loss of 53.5% and a modulation depth of 9.8%.Stable fundamentally mode-locked solitons at 1909.5 nm with distinct Kelly sidebands on the output spectrum,a pulse repetition rate of 21.5 MHz,and a measured pulse width of 1.26 ps were observed in the work.By increasing the pump power,both bunched solitons with soliton number up to 15 and harmonically mode-locked solitons with harmonic order up to 10 were obtained.To our knowledge,this is the first report of both bunched solitons and harmonically mode-locked solitons in a fiber laser at 2 μm region incorporated with TIs.
