一种基于粗糙均方残基的模糊双聚类方法

双聚类作为一种无监督的学习方法,其作用是对基因表达数据进行分析.为了获取较大容量的双聚类簇,弥补传统的双聚类方法在基因表达数据一致波动性方面的不足,引入粗糙集的上、下近似集概念,将粗糙集理论运用到模糊双聚类算法中,将粗糙上、下近似集与加权均方残差相结合,得到新的粗糙均方残基,进而提出一种基于粗糙均方残基的模糊双聚类算法.针对基因表达数据集,首先进行缺失值填补;其次,用非负矩阵分解算法对基因数据集进行降维;最后,计算数据矩阵的粗糙均方残基,结合综合评判度量函数与贴近度原则对矩阵的行列进行删除和添加,得到容量更大的双聚类结果.实验结果表明,该模糊双聚类算法是有效的.

甘露消毒丹对感染肠道病毒71型细胞miRNA-155表达的影响

目的观察甘露消毒丹及其残方对肠道病毒71型(EV71)感染后的RD细胞miRNA-155表达的影响。方法运用细胞培养技术,设甘全方组、清残方组、利残方组、利巴韦林组、正常细胞对照组、模型对照组,将药物作用于EV71感染后的RD细胞,24 h后RT-PCR法检测各组细胞miR-155表达。结果 1)模型对照组、甘全方组、清残方组、利巴韦林组miR-155表达均比正常细胞对照组低,利残方组比正常细胞对照组升高(P<0.05或P<0.01);甘全方组、清残方组、利残方组miR-155的表达比模型对照组高(P<0.05或P<0.01),利巴韦林组与模型对照组差异不明显(P>0.05);甘全方组、清残方组、利残方组miR-155表达比利巴韦林组升高(P<0.05或P<0.01),清残方组、利残方组的表达比甘全方组升高(P<0.05或P<0.01),利残方组最高。结论 EV71感染RD细胞后miR-155表达降低,与文献报道趋势不同,提示其表达可能具有细胞特异性;甘全方、清残方、利残方均能上调EV71感染后miR-155的表达从而调控免疫反应;利残方与清残方之间可能存在相互拮抗关系。

Effect of aggregation interval on vehicular traffic flow heteroscedasticity

The effect of the aggregation interval on vehicular traffic flow heteroscedasticity is investigated using real-world traffic flow data collected from the motorway system in the United Kingdom. 30 traffic flow series are generated using 30 aggregation intervals ranging from 1 to 30 min at 1 min increment, and autoregressive integrated moving average （AR/MA） models are constructed and applied in these series, generating 30 residual series. Through applying the portmanteau Q-test and the Lagrange multiplier （LM） test in the residual series from the ARIMA models, the heteroscedasticity in traffic flow series is investigated. Empirical results show that traffic flow is heteroscedastJc across these selected aggregation intervals, and longer aggregation intervals tend to cancel out the noise in the traffic flow data and hence reduce the heteroscedasticity in traffic flow series. The above findings can be utilized in the development of reliable and robust traffic management and control systems.

购房与租房的实证分析

房价与民生息息相关,房价的过快增长,会加重人民负担,增加社会成本,激化社会矛盾。因此房价问题是当前的重要课题。而国家政策意图通过鼓励租房来解决房价过高的问题。因此,探讨这个选择也是必要的房价问题是当前的重要课题。而国家政策意图通过鼓励租房来解决房价过高的问题。因此,探讨这个选择也是必要的。我们综合分析结果以及政府的宏观政策,中国宏观经济形势向青年提出建议:认清现实,青年步入社会的初期适合租房,有一定资金积累后适合买房。

PIEZOSPECTROSCOPIC STUDY OF RESIDUAL STRESSES AROUND INDENTATIONS IN SiC/Al_O_3 NANOCOMPOSITE

A new experimental measurement of residual stresses around Vickers′ indentations on the surface of the SiC/Al 2O 3 nanocomposites is proposed with the aid of a Raman microprobe. Results s how that the shifts of R lines in the fluorescence spectra va ry with the distance from the centre of indentation. The magnitude of load appli ed on the surface of the materials through the indenter influences the shifts of R lines to great extent. The luminescence of R lines of the materials before indenting is used to determine the residual stresses around the indentation in the materials, assuming that the stress tensor is transversely isotropic. Final ly, the term of hydrostatic stress is adopted to explain and compare different residual stresses around indentations with the increase of the indenting load an d the distance from the centre of indentations. <

李晶治疗消化道肿瘤经验

李晶教授认为,脾胃虚弱为消化道肿瘤病机关键,虚、寒常兼见,瘀毒常兼夹为病,且消化道肿瘤患者长期情志不舒,则肝气郁结,木郁克土,运化失常,则气机升降无度,治宜温补中焦,理气为上,升降同调,祛瘀生肌,佐以解毒,腑气调和,上下协调等,自拟残胃方治疗。脾胃虚弱甚者采用四君子汤加减;气虚郁结者采用四逆散加减;久病伤血入络,脉络瘀阻者采用石见穿之类活血化瘀,白及消肿生肌。便秘者加杏仁、紫苏子、防风、郁李仁、柏子仁等;腹泻者加石榴皮、乌梅、益智仁;祛风除湿可加徐长卿、羌活、防风等。

A Multi-level Approach for Complex Fault Isolation Based on Structured Residuals

In industrial processes,there exist faults that have complex effect on process variables.Complex and simple faults are defined according to their effect dimensions.The conventional approaches based on structured residuals cannot isolate complex faults.This paper presents a multi-level strategy for complex fault isolation.An extraction procedure is employed to reduce the complex faults to simple ones and assign them to several levels.On each level,faults are isolated by their different responses in the structured residuals.Each residual is obtained insensitive to one fault but more sensitive to others.The faults on different levels are verified to have different residual responses and will not be confused.An entire incidence matrix containing residual response characteristics of all faults is obtained,based on which faults can be isolated.The proposed method is applied in the Tennessee Eastman process example,and the effectiveness and advantage are demonstrated.

Partial least squares regression for predicting economic loss of vegetables caused by acid rain

To predict the economic loss of crops caused by acid rain,we used partial least squares(PLS) regression to build a model of single dependent variable -the economic loss calculated with the decrease in yield related to the pH value and levels of Ca2+,NH4+,Na+,K+,Mg2+,SO42-,NO3-,and Cl-in acid rain. We selected vegetables which were sensitive to acid rain as the sample crops,and collected 12 groups of data,of which 8 groups were used for modeling and 4 groups for testing. Using the cross validation method to evaluate the performace of this prediction model indicates that the optimum number of principal components was 3,determined by the minimum of prediction residual error sum of squares,and the prediction error of the regression equation ranges from -2.25% to 4.32%. The model predicted that the economic loss of vegetables from acid rain is negatively corrrelated to pH and the concentrations of NH4+,SO42-,NO3-,and Cl-in the rain,and positively correlated to the concentrations of Ca2+,Na+,K+ and Mg2+. The precision of the model may be improved if the non-linearity of original data is addressed.

Shear creep characteristics and constitutive model of limestone

The characters of limestone in weak interlayer of a high rocky slope in Xuzhou, China, are studied by shear static test and shear creep test. The results show that limestone specimens have attenuation creep properties and constant rate creep properties, almost have no accelerated creep properties. The exponential type empirical formula is selected to fit creep grading curves by polynomial regression analysis method, and the square sums of the fitting results residual are in the order of 10^(-7). Then grade creep curves at every shear loads are set up. Combining creep rate-time curve, the creep properties of limestone are analyzed. As the physical meaning of component model is clearer, the Poytin–Thomson model is set up. Through the least square method, the optimal parameters of Poytin–Thomson model are obtained,and the sums of squared residuals belong to 10^(-3)order of magnitude, which can meet the accuracy requirements of engineering calculation. So the Poytin–Thomson model can reflect the shear creep characteristics of limestone very well.

Identity-based ring signature scheme based on quadratic residues

Identity-based （ID-based） ring signature has drawn great concerns in recent years and many ID-based ring signature schemes have been proposed until now. Unfortunately, all of these ID-based ring signatures are constructed from bilinear pairings, a powerful but computationally expensive primitive. Hence, ID-based ring signature without pairing is of great interest in the field of cryptography. In this paper, the authors firstly propose an ID-based ring signature scheme based on quadratic residues. The proposed scheme is proved to be existentially unforgeable against adaptive chosen message-and-identity attack under the random oracle model, assuming the hardness of factoring. The proposed scheme is more efficient than those which are constructed from bilinear pairings.

Influence of Residual Stress on the Elastic-plastic Response to Indentation

The indentation method is useful in determining the residual stress according to the elastic-plastic properties of materials.So the effect of the residual stress on the elastic-plastic indentation properties of materials was studied by using the finite element method to find better indentation parameters which are strongly induced by the residual stress.The results show that load-depth curve,plastic pile-up,indentation shape,indentation contact stress and indentation residual stress are affected by different residual stress,and these parameters can be used to deduce the residual stress.Also,a special indentation equipment was developed to analyze the elastic-plastic properties of materials with different residual stress,and the experimental results show a good agreement with the FEM results.For practical application,the elastic-plastic indentation properties of materials with unknown residual stress could be obtained by the developed equipment to deduce the residual stress comprehensively.

Determination of Residual Enrofloxacin in Fish Tissues by Terbium Ion-sensitized Fluorophotometry

In order to establish a new method for the determination of enrofloxacin, on the basis of the fluorescence characteristic of terbium-enrofloxacin complex, it was found that in a HAc-NaAc buffer solution with a pH value at 6.0, the terbiumenrofloxacin complex had a characteristic fluorescence peak of Tb3＋ at 545 nm （λex= 328 nm）, which could be used for the determination of enrofloxacin. A simple, rapid and sensitive fluorescence method for the determination of enrofloxacin was thus established, and an optimal reaction condition was selected. Under the optimal reaction condition, there was a good linear relation （r2=0.992 3） between concentration of enrofloxacin in the range of 1.0×10^-1.0×10^-6 g/ml and its fluorescence intensity at 545 nm, with a detection limit of 1.3×10^-9 g/ml; the recovery for enrofloxacin in tablets was 97.7% with a variation coefficient of 1.4%; and for enrofloxacin in fish tissues, the recovery was 79.0%-94.5% with a variation coefficient of 2.0%-7.8%.

Effect of gear teeth finishing method on properties of teeth surface layer and its resistance to pitting wear creation

This work presented the characteristics of two gear teeth finishing methods, due to the properties of gear teeth surface layer obtained at the tooth working depth. These methods are: 1) the teeth carburization, hardening to a hardness of HRC 60-62 and then grinding, 2) the soft gear shaving as the final mechanical treatment and then carburizing and hardening to the hardness of HRC60-62. This work included the test results of the contact fatigue strength carried out on the circulating power system. The Wohler curves were plotted due to the obtained results, as the basis for the practical evaluation of the considered gear finishing methods. The parameters like volume distribution of the voids, content of the retained austenite, compressive residual stress value, but also the results of contact fatigue strength tests, are more favorable for the teeth shaving method than for the teeth grinding method.

Retained placenta: Do we have any option?

Retained placenta is a known cause of post-partum haemorrhage and maternal mortality. A recent systemic review has confirmed that the incidence of retained placenta had increased all over the world, which is more common in developed countries. Failure of retroplacental myometrium contraction is the main cause of retained placenta. Maternal age greater than 35 years, grandmultipara, preterm labor, history of previous retained placenta, and caesarean section were the risk factors for retained placenta. Manual removal of the placenta has been the treatment of choice. Attempts had been made by clinician and researchers to find a safe, effective and reliable method to avoid the need for surgical intervention. The efficacy and safety of prostaglandin, nitroglycerin or acupuncture in the management of retained placenta are yet to be further evaluated. Nonetheless, till date only intraumbilical vein oxytocin has been studied extensively but with varied success. More randomized clinical trials are needed to address this issue. However, if immediate manual placenta removal service is unavailable, a trial of intra-umbilical vein oxytocin 100 IU at a totalvolume of at least 40 m L while preparing for transfer to a tertiary center or theatre may result in spontaneous expulsion of the placenta.

Effect of welding sequence on residual stress and deformation of 6061-T6 aluminium alloy automobile component

Four different welding sequences of double-pulse MIG welding were conducted for 6061-T6 aluminum alloy automobile bumpers by using nonlinear elastoplasticity finite element method based on ABAQUS software.The post-welding residual stress and deformation were definitely different among the four welding sequences.The results showed that the highest temperature in Solution A was approximately 200℃higher than the melting point of base metal.High residual stress was resulted from this large temperature gradient and mainly concentrated on the welding vicinity between beam and crash box.The welding deformation primarily occurred in both of the contraction of two-ends of the beam and the self-contraction of crash box.Compared with other welding sequences,the residual stress in Solution A was the smallest,whereas the welding deformation was the largest.However,the optimal sequence was Solution B because of the effective reduction of residual stress and good assembly requirements.

A new damping ratio identification method based on pattern search

In order to improve the effectiveness of traditional time domain identification methods in identifying damping ratios, a new damping ratio identification method based on pattern search is proposed by fluctuating the reliable natural frequency obtained through traditional time domain identification methods by about 10% to build the boundary conditions, using all the initial identification results to establish the free decay response of the system, and using the pattern search method to correct the initial identification results with the residual sum of squares between the free decay response and the actually measured free-decay signal as the objective function. The proposed method deals with the actually measured free-decay signal with curve fitting and avoids enlarging the identified error caused by intermediate conversion, so it can effectively improve the identified accuracy of damping ratios. Simulations for a room-sized vibration isolation foundation show that the relative errors of analyzed three damping ratios are down to 1.05%, 1.51% and 3.7% by the proposed method from 8.42%, 5.85% and 8.5% by STD method when the noise level is 10%.

Effects of N/Z on Spin Distribution of Evaporation Residue Cross Section as a Probe of Nuclear Dissipation

The spin distribution of the evaporation residue cross section of nuclei ^194pb, ^200Pb, ^206Pb, and ^200 Os are calculated via a Langevin equation coupled with a statistical decay model. It is shown that with increasing the neutronto-proton ratio （N/Z） of the system, the sensitivity of the significantly. Moreover, for ^200Os this spin distribution is no spin distribution to the nuclear dissipation is decreased longer sensitive to the nuclear dissipation. These results suggest that to obtain a more accurate pre-saddle viscosity coefficient through the measurement of the evaporation residue spin distribution, it is best to yield those compound systems with low N/Z.

Effect of PCBN cutting tools wear on surface integrality in high-speed hard turning

In this paper, the effect of of flank wear polycrystalline cubic boron nitride （PCBN） tools on residual stresses, white layer and roughness of machined workpiece surfaces is studied. Experimental results indicate that with the increase of the tool wear, the surface of the machined workpiece tends to generate tensile residual stresses, and white layer becomes clearly thicker and uneven on the workpiece surface. The effect of the flank wear on the surface roughness is less within some range of flank wear value. The results show that it is possible to produce ideal surface integrality levels by controlling the tool flank wear.

Ways of constructing optimal magic cube of order n when (n,2·3·5·7)=1

An optimal magic cube of order n is a magic cube whose row sums, column sums and oblique sums of 9 n layers are n(n 3+1)/2. The author proved that optimal magic cubes of order n may be constructed as long as n and 2, 3, 5, 7 are relatively prime, and a formula for making optimal magic cubes by using optimal Latin squares and optimal magic squares was given.

SPE-HPLC Method for the Determination of Avermectin Residues in Milk and Beef

Here we propose a method for determination of Avermectin residual content in milk and beef content. After extracting and processing the sample, use high performance liquid chromatography （HPLC） for determination. Mobile phase is： V（Methanol）： V（Water）=90： 10; determination wavelength is 245 nm; flow rate is 0.8 mL/min. Avermectin is completely separated in 17min, linear range is 5 - 0.3 g/L, correlation coefficient is 0.9997, average recovery rates of Avermectin in milk and beef are respectively 91.20 %- 100.32 % and 89.93 %-99.15 %, the relative standard deviations are respectively less than 7% and 4%. This method is simple, sensitive and accurate, so is suitable for determination of Avermectin residues in milk and beef, and it can meet domestic and foreign testing requirements.