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181.
182.
The Empirical Bayes Estimation of the Location Parameter in Double-Exponential Family under the LINEX Loss Function 下载免费PDF全文
In this paper, we derive the Bayes estimator of the location
parameter in double-exponential family under the LINEX loss function, and then construct
the corresponding empirical Bayes estimator. It is shown that the empirical Bayes
estimator is asymptotically optimal with convergence rate being ,
, where 1/2相似文献
183.
产品/服务配置规则获取的主要方式是用数据挖掘技术从设计实例数据库中提取.客户化服务方案配置规则为服务功能需求和方案特征间的关联规则.考虑到常用关联规则挖掘算法Apriori具有运算复杂的缺点,提出基于PIETM(Principle of Inclusion—Exclusion and Transaction Mapping)算法的配置规则挖掘方法,考虑置信度和有趣度指标,提取强关联规则.针对配置实例数据库数据量较大时,配置规则挖掘的效率会降低且会产生大量冗余规则的问题,采用二元语义模型表达定性的服务功能需求,将同类客户群的功能需求进行合并,替换多样化的功能需求,减少规则的冗余.最后以一工程机械制造企业服务方案配置规则挖掘为例,验证了所提方法的有效性. 相似文献
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This article is a brief overview of the emerging microfluidic systems called surface‐tension‐confined microfluidic (STCM) devices. STCM devices utilize surface energy that can control the movement of fluid droplets. Unlike conventional poly(dimethylsiloxane)‐based microfluidics which confine the movement of fluids by three‐dimensional (3D) microchannels, STCM systems provide two‐dimensional (2D) platforms for microfluidics. A variety of STCM devices have been prepared by various micro‐/nanofabrication strategies. Advantages of STCM devices over conventional microfluidics are significant reduction of energy consumption during device operation, facile introduction of fluids onto 2D microchannels without the use of a micropump, increased flow rate in a special type of STCM device, among others. Thus, STCM devices can be excellent alternatives for certain areas in microfluidics. In this Minireview, fabrication methods, operating modes, and applications of STCM devices are introduced. 相似文献
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Jian‐You Li Ying Peng Ling‐Zhi Li Pin‐Yi Gao Chang Gao Su‐Xia Xia Shao‐Jiang Song 《Helvetica chimica acta》2013,96(2):313-319
Two new abietane‐type diterpenoids, named triptobenzene R ( 1 ) and triptobenzene S ( 2 ), together with three known abietane‐type diterpenoids, triptophenolide ( 3 ), triptonodiol ( 4 ), and triptonoterpene methyl ether ( 5 ), were isolated from the roots of Tripterygium wilfordii Hook . f. Their structures and relative configurations were established by detailed spectral studies, including 1D‐ and 2D‐NMR (HSQC, HMBC, and NOESY), and HR‐ESI‐TOF‐MS, and by comparison with published data. Their absolute configurations were assigned by the CD technique, applied for the first time to abietane diterpenes from Tripterygium wilfordii. Compound 2 is the first abietane‐type norditerpenoid isolated from the genus Tripterygium. 相似文献
189.
The reaction of halogenated 9H-carbazoles or carbazole with bromoesters in DMF under microwave irradiation readily affords a series of 9H-carbazoles-9-hydroxylic acids. 相似文献
190.
A new azido-coordinated nickel(II) complex [NiL1(N3)] (1) and a new thiocyanato-coordinated nickel(II) complex [NiL2(NCS)] (2), where L1 and L2 are the monoanionic forms of Schiff bases 2-[(2-isopropylaminoethylimino)methyl]-6-methylphenol and 2-[(2-dimethlaminoethylimino)methyl]-6-methylphenol respectively, are prepared and structurally characterized by elemental analysis, IR spectra, and single crystal X-ray crystallography. Complex 1 crystallizes in the triclinic space group P-1 with unit cell dimensions a = 8.812(2) Å, b = 9.433(3) Å, c = 9.488(2) Å, α = 81.933(2)°, β = 69.925(2)°, γ = 84.591(2)°, V = 732.5(3) Å3, Z = 2, R 1 = 0.0291, and wR 2 = 0.0734. Complex 2 crystallizes in the monoclinic space group P21/n with unit cell dimensions a = 7.4497(4) Å, b = 6.1933(3) Å, c = 31.5126(18) Å, β = 92.484(2)°, V = 1452.57(13) Å3, Z = 4, R 1 = 0.0307, and wR 2 = 0.0668. The Ni atom in each of the complexes is coordinated by three donor atoms of the Schiff base ligand and by one N atom of the azide or thiocyanate ligand, forming a square planar geometry. The azide and thiocyanate anions readily coordinate to the complexes as secondary ligands. 相似文献