住宅房地产顾客感知价值评估

不同的顾客对同一住宅房地产的感知价值是不同的,购房决策主要取决于对住宅房地产的顾客感知价值.提出了住宅房地产顾客感知价值评估的质量功能配置逆过程法,在已知住宅房地产工程特性的条件下,确定顾客需求值.利用该方法,给出了评估住宅房地产的顾客感知价值的过程和数学模型,案例研究表明,方法能有效评估住宅房地产的顾客感知价值,帮助购房者选择住宅房地产项目.     

M/M/1/m系统算子的本征值特性(m=7,8)

研究了m=7,8时,M/M/1/m算子本征值特性:相应本征值的代数重为1;m=7,8时,相应的系统算子的非零本征值相互交替;m=8时的最大非零本征值比m=7时更靠近0点.这种特性延续了m=1,2,3,4,5,6时相应的特性.另外给出了m=7,8时,相应的p_0(t)图像.     

基于灰色理论的温州房价预测模型

以温州统计局有关房地产销售数据为分析对象,用销售总面积和销售总额折算成价格指标,采用灰色系统GM(1,1)建立数学模型对房屋价格指标进行分析和预测.基于投资回报周期和预期心理,对2007至2010年的房价作两次平移整理后再进行建模,效果更为理想.利用模型对.2011年上半年房价进行预测与市场行情吻合性程度高.     

Molecular-beacon-based tricomponent probe for SNP analysis in folded nucleic acids

Hybridization probes are often inefficient in the analysis of single‐stranded DNA or RNA that are folded in stable secondary structures. A molecular beacon (MB) probe is a short DNA hairpin with a fluorophore and a quencher attached to opposite sides of the oligonucleotide. The probe is widely used in real‐time analysis of specific DNA and RNA sequences. This study demonstrates how a conventional MB probe can be used for the analysis of nucleic acids that form very stable (T_m>80 °C) hairpin structures. Here we demonstrate that the MB probe is not efficient in direct analysis of secondary structure‐folded analytes, whereas a MB‐based tricomponent probe is suitable for these purposes. The tricomponent probe takes advantage of two oligonucleotide adaptor strands f and m. Each adaptor strand contains a fragment complementary to the analyte and a fragment complementary to a MB probe. In the presence of a specific analyte, the two adaptor strands hybridize to the analyte and the MB probe, thus forming a quadripartite complex. DNA strand f binds to the analyte with high affinity and unwinds its secondary structure. Strand m forms a stable complex only with the fully complementary analyte. The MB probe fluorescently reports the formation of the quadripartite associate. It was demonstrated that the DNA analytes folded in hairpin structures with stems containing 5, 6, 7, 8, 9, 11, or 13 base pairs can be detected in real time with the limit of detection (LOD) lying in the nanomolar range. The stability of the stem region in the DNA analyte did not affect the LOD. Analytes containing single base substitutions in the stem or in the loop positions were discriminated from the fully complementary DNA at room temperature. The tricomponent probe promises to simplify nucleic acid analysis at ambient temperatures in such applications as in vivo RNA monitoring, detection of pathogens, and single nucleotide polymorphism (SNP) genotyping by DNA microarrays.     

The entropic discriminant

The entropic discriminant is a non-negative polynomial associated to a matrix. It arises in contexts ranging from statistics and linear programming to singularity theory and algebraic geometry. It describes the complex branch locus of the polar map of a real hyperplane arrangement, and it vanishes when the equations defining the analytic center of a linear program have a complex double root. We study the geometry of the entropic discriminant, and we express its degree in terms of the characteristic polynomial of the underlying matroid. Singularities of reciprocal linear spaces play a key role. In the corank-one case, the entropic discriminant admits a sum of squares representation derived from the discriminant of a characteristic polynomial of a symmetric matrix.     

复空间形式中具有常数量曲率的全实子流形

本文研究了复空间形式中具有常数量曲率的全实子流形.利用一种自伴算子,得到了这类子流形关于第二基本形式模长平方的积分不等式.     

Photonic time‐stretch digitizer and its extension to real‐time spectroscopy and imaging

Real‐time wideband digitizers are the key building block in many systems including oscilloscopes, signal intelligence, electronic warfare, and medical diagnostics systems. Continually extending the bandwidth of digitizers has hence become a central challenge in electronics. Fortunately, it has been shown that photonic pre‐processing of wideband signals can boost the performance of electronic digitizers. In this article, the underlying principle of the time‐stretch analog‐to‐digital converter (TSADC) that addresses the demands on resolution, bandwidth, and spectral efficiency is reviewed. In the TSADC, amplified dispersive Fourier transform is used to slow down the analog signal in time and hence to compress its bandwidth. Simultaneous signal amplification during the time‐stretch process compensates for parasitic losses leading to high signal‐to‐noise ratio. This powerful concept transforms the analog signal's time scale such that it matches the slower time scale of the digitizer. A summary of time‐stretch technology's extension to high‐throughput single‐shot spectroscopy, a technique that led to the discovery of optical rouge waves, is also presented. Moreover, its application in high‐throughput imaging, which has recently led to identification of rogue cancer cells in blood with record sensitivity, is discussed.