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941.
942.
Geometric programming (GP) is suggested as an analytical toolfor solving replacement problems with infinite time horizon.The GP solution method is described and explained through theformulation and solution of a typical replacement problem. Asimple example is worked out to demonstrate the pint that GPhas potential as an appropriate mathematical tool for the analysisof certain types of replacement problems. 相似文献
943.
944.
After the cultured cells from Hyoscyamus muticus + Nicotiana tabacum somatic hybridswere cocultivated with different virulent strains of Agrobacterium tumefaciens harboringoctopine- type Ti plasmid or nopaline- type Ti plasmid using the transformation procedurein vitro developed in the present investigation, the TiT- DNA genes were introducedinto the host cells. The onc genes and ocs or nos genes located on TiT- DNA were expres-sed in transformed colonies derived from the cocultivated cells. Although the platingefficiencies of recipient cells were reduced by the agrobacterial treatment, the frequenciesof phytohormone autotrophy ranged from 33.9 to 76 .8% in the cells infected with viru-lent strains in hormone- free conditions, and the frequencies of opine synthase activityamounted to 9.7- 47 .5%. Teratomatous shoots were regenerated from the transformed col-onies. During the course of culture the shoots were no longer to lengthen when theygrew up to 1 -3 cm in length, and they could not be rooted. Follo 相似文献
945.
946.
为解决红外图像和可见光图像在夜视环境下成像效果不理想的问题,搭建一种由红外相机与RGB相机组合而成的具有结构简单、实时性高等特点的双目异型成像系统。利用双线程方式实时采集红外与可见光图像,针对非局部均值滤波(Non Local Mean,NLM)提出了一种基于熵的自适应h求解方法,能够较好的消除红外图像的噪声;之后将红外图像与可见光图像的特征点匹配后,引入基于斜率一致性的方法进行图像配准,最后采用改进基础图像融合规则的双尺度融合算法(Twoscale Image Fusion,TIF)以及多种融合算法将红外与可见光图像进行融合,获得目标明显、信息丰富且真实色彩的(Infrared Radiation and RGB,IR RGB)融合图像。TIF算法能够高效快速地将红外图像与可见光图像融合,在保留了可见光图像对周围环境的真实颜色信息特征的同时,又保留了红外图像温度提取的特点。分析数据可知,TIF算法的IR RGB图像的熵值提升了约514;其边缘强度均达到最大39991、 22433、 52880;相比普通的像素级融合规则,该方法的运行速度提升了10倍的量级。该研究在夜视环境下通过红外与可见光的实时成像在目标识别和监测等实际应用中具有非常重要的意义。 相似文献
947.
948.
The Cu(Ⅱ) and Co(Ⅱ) supramolecular coordination polymers, [CuCl2(DPO)- (CH3CN)0.5(CH2Cl2)0.5]n (CuDPO, DPO = rctt-1,3-diphenyl-2,4-bis[2-(5-phenyl)oxazolyl]cyclo- butane) and [CoCl2(DPO)]n (CoDPO), were synthesized and characterized by single-crystal X-ray diffraction method. CuDPO crystallizes in monoclinic, space group P21/n, with a = 11.243(5), b = 16.070(8), c = 19.872(9) A, β = 95.678(10)°, Z = 4, V= 3573(3) A3, C35.50H28.50Cl3CuN2.50O2, Mr = 692.00, Dc = 1.287 g/cm3, p = 0.868 mm^-1, F(000) = 1420, S = 1.089, (△/σ)max = 0.069, the final R = 0.0682 and wR = 0.1749. CoDPO is of monoclinie, space group P21/n, with a = 11.396(4), b = 15.151(5), c = 17.673(6) A, β = 90.528(6)°, Z = 4, V = 3051.4(17) A3, C34H26Cl2CoN2O2, Mr = 624.40, Dc = 1.359 g/cm3, μ = 0.770 mm^-1, F(000) = 1284, S = 0.981, (△/σ)max = 0.001, the final R = 0.0471 and wR = 0.0961. In each case, the metal cation is coordinated by two C1 anions and two N atoms from oxazole ring of the ligands, which leads to the formation of a one-dimensional polymeric structure. It is found that the cyclobutane ring of coordinated DPO adopts a distorted conformation in the crystal, which is attributed to the increased steric effect between adjacent aryl substituents for the coordination of oxazole ring to metal cation. Thermal gravimetric analysis of the two complexes was also observed. 相似文献
949.
The additional symmetries of the constrained CKP (cCKP) and BKP (cBKP) hierarchies are given by their actions on the Lax operators, and their actions on the eigenfunction and adjoint eigenfunction {Φ i , Ψ i } are presented explicitly. Furthermore, we show that acting on the space of the wave operator, *k forms new centerless W cC 1+∞ and W cB 1+∞ -subalgebra of centerless W 1+∞ respectively. In order to define above symmetry flows *k of the cCKP and cBKP hierarchies, two vital operators Y k are introduce... 相似文献
950.
研究了具有HollingII类型功能反应的一捕食者有两个食饵的时滞系统,通过构造Lyapunov泛函得到了与时滞有关的系统全局渐近稳定的充分条件. 相似文献