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11.
针对一类具有物种流动时特定区域内的种群增长差分方程模型,采用数值模拟方法给出了Lyapunov指数随参数变化的图形,验证了混沌现象的存在.采取OGY参数微扰法进行混沌控制,使种群稳定到不动点和周期2轨道,消除了种群的混沌现象.仿真结果验证了控制的有效性.  相似文献   
12.
CTSP问题稳态小生境算法的研究及仿真实现   总被引:2,自引:0,他引:2  
提出了一种求解中国旅行商问题(CTSP)的稳态小生境遗传算法SNGA。SNGA算法在稳态遗传算法的基础上采用物种保存小生境替换策略,在改善算法的在线性能、离线性能和计算量的同时,有效的维持了群体的多样性,从而可避免群体出现早熟现象,增强群体在进化后期产生优良模式的能力。在具体实现中,SNGA算法采用链表染色体编码,这样就可以对染色体进行快速的基本遗传算子以及倒位算子的遗传操作,进一步提高算法的实现性能。此外采用C 语言和基于COM的MapObjects组件技术实现了基于上述算法的仿真软件GISCTSP,并对国家基础地理信息系统(NFGIS)1400万中国行政中心数据文件res1_4m进行了仿真分析。  相似文献   
13.
描述中国七叶树Aesculus chinensis 2种新瘿螨和1中国新纪录种,即七叶树谢氏瘿螨,新种Shevtchenkella aesculichina sp.nov.,七叶树大嘴瘿螨,新种Rhyncaphytoptus aesculus sp.nov.和加利福尼亚七叶树谢氏瘿螨Shevtchenkella aes...  相似文献   
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Sponge fauna from the west and south of Svalbard archipelago was studied. A total of 28 species of sponges were identified. Five of them are new records to the study area and one is new to science. New records for Spitsbergen are: Axinella hispida (Koltun 1959), Haliclona rossica (Hentschel 1929), Myxilla (Myxilla) perspinosa (Lundbeck 1905), Sphaerotylus borealis (Swartschewsky 1906) and Suberites carnosus (Johnston 1842). A new species of sponge, Halicnemia wagini sp. nov., collected south-west of Spitsbergen on the continental slope at a depth of 423–425 m, is described. It is similar to Halicnemia patera (Bowerbank 1864) and H. verticillata (Bowerbank 1866) in skeleton architecture, but significantly differs in its spicule complement and external appearance. Primarily, distinct differences concern the morphology of microscleres. In comparison with Halicnemia patera, the new species has an additional category of acanthose microscleres presented by microstrongyles, while microscleres of H. verticillata are only slightly curved and also verticillately spined. The study area, west of Spitsbergen, establishes close relationships with North Atlantic due to warm Atlantic waters of the West Spitsbergen Current. Proximity of the new species to the North Atlantic representatives of Halicnemia genus allowed us to suggest that H. wagini sp. nov., both ecologically and morphologically, has stood apart as a distinct biological species in the conditions of the Arctic.

http://www.zoobank.org/lsid:zoobank.org:pub:2A09537B-63D7-4F07-A2AB-9C707A686333  相似文献   

17.
The South Korean species of the genus Exochus are revised. Ten new species, Exochus acostulatus Lee & Choi, sp. nov., Exochus adentatus Lee & Choi, sp. nov., Exochus areolaris Lee & Choi, sp. nov., Exochus carinalis Lee & Choi, sp. nov., Exochus dentisternum Lee & Choi, sp. nov., Exochus depressus Lee & Choi, sp. nov., Exochus nigritulus Lee & Choi sp. nov., Exochus occipitalis Lee & Choi, sp. nov., Exochus orbitalis Lee & Choi, sp. nov. and Exochus propodealis Lee & Choi, sp. nov., are described. Also, 21 species of this genus are reviewed and newly recorded from South Korea, with diagnoses provided. A key to the South Korean species of Exochus and illustrations of external characters are provided.

http://zoobank.org/urn:lsid:zoobank.org:pub:B28700A7-9CA7-4AE7-9816-9C8F4CD46160  相似文献   

18.
A long-term survey of tritrophic (plant–aphid–parasitoid) associations in the urban ecosystems of Lleida (Catalonia) and Paris (France) resulted in the detection of associations of two bamboo aphids, Takecallis arundinariae (Essig) and Takecallis taiwanus (Takahashi), respectively, with a new aphid parasitoid species. Trioxys remaudierei Starý & Rakhshani sp. nov. is described and illustrated as a unique parasitoid of Takecallis aphids outside the area of their origin. The new species is easily distinguishable from its congeners in having the ventral prongs of the abdomen fused over two-thirds of their length, then bifurcated towards the tip. The only morphologically similar species is Trioxys betulae (Marshall), which exhibits a clearly different prong shape (and has a different host range, Symydobius Mordvilko and Clethrobius Mordvilko). The new species is compared with allied taxa associated with bamboo aphids. The occurrence of Takecallis taiwanus on bamboo is recorded in France for the first time.

www.zoobank.org/urn:lsid:zoobank.org:pub:ED15BA16-E8A9-4CEA-BDA7-FBAB02FEB091  相似文献   

19.
Japanese fauna of the cimicomorphan family Microphysidae is documented. Four species of the genus Loricula Curtis are recognised, including three new species herein described from Japan, Loricula miyamotoi, L. nikko and L. yakushima, representing the first discovery of new taxa in the twenty-first century for the Asian Microphysidae. A single known species, L. pilosella Miyamoto, is rediagnosed. A key is provided to distinguish both sexes of the Japanese Loricula species.

http://zoobank.org/urn:lsid:zoobank.org:pub:C01445E4-FD3E-4953-932C-7835FC8BDD16  相似文献   

20.
The present study summarizes additions to the known fauna of Eucharitidae of Saudi Arabia. Cherianella arabica Gadallah &; Soliman sp. nov. and the male of previously known female Eucharis (Psilogastrellus) albipennis Bou?ek, 1956 are described and illustrated. Three new records are also added to the fauna of Saudi Arabia: Eucharis (Eucharisca) intermedia Ruschka, 1924, Eucharis (Psilogastrellus) acuminata Ruschka, 1924 and Eucharis (Psilogastrellus) punctata Förster, 1859.

http:/zoobank.org/urn:lsid:zoobank.org:pub:F1B1C493-AA83-4696-AF8B-3B3F62C09B41  相似文献   
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