不同分样方法对碎米检验结果的影响

通过对《粮油检验碎米检验法》(GB/T55503—2009)国家标准中分样方法的探讨,表明采用不同的分样方法对双试验结果绝对差值有较大的影响,为保证双试验结果绝对差值符合标准规定,建议采用分样板和分样器联合分样法分取样品。

粮食分样设备和分样方法的两项改进

目前粮食收储行业中的粮食扦取样品后的分样状况包括所使用的分样仪器和分样方法,存在着样品代表性差、方法杂乱、效率低下、人为因素仍然过重等不少的弊端和困惑,亟待改进和提高.本文介绍了一款粮食接收中使用的新型分样器和一种适合粮仓内采用的新的分样方法,经过实践比对、验证和实际工作的运用,达到了分样科学准确、方法统一、操作规范,高效快捷的良好效果,对提高检验行业更好的实现仪器化操作,实现粮油质量上更科学精准的检验管理意义非常重大。

玉米样品分样和制备对DON测量结果影响的分析

通过实验测定不同分样和制备方法下玉米中DON含量,利用数理统计方法进行比较,尝试确定可行的分样量和分样方法,以达到既具有代表性、又减少工作量、提高效率的最佳方案。同时研究了杂质对测定结果的影响。

Calculation and Analysis of Near Field of Airborne Short Wave Antenna

Aim To calculate and analyze the near field distribution of ariborne short wave antenna. Methods B-spline method was used to get the mathermatital model of a Boeing 707320Baircraft and simulate its short wave antenna . FDTD (finite-difference time-domain) method are ed tO complete the calculation and analysis. Results The near field distributions on aircraft's surface were obtained, the curve and gray figures of the normalized near field value were shown. Conclusion These modeling and calculating methods can provide data foraircraft's EMC analysis and design.

Determination of Trace Copper (Ⅱ) in Water Samples by Kinetic-spectrophotometry

A new kinetic-spectrophotometric method is proposed for the determination of copper (Ⅱ). The method is based on the catalytic effect of copper (Ⅱ) on the oxidation of weak acid brilliant blue dye (RAWL) by hydrogen peroxide. The copper (Ⅱ) can be determined spectrophotometrically by measuring the decrease of absorbance of RAWL at λ = 626 nm using the fix-time method. The optimum reaction conditions are as follows: pH 7.20, buffer solution NaOH-KH2PO4, RAWL (200 mg L-1) 5.00 mL, H2O2 (30%) 0.50 mL, reaction temperature 80℃ and reaction time 20 min. The linear range of this method is between 0 μg L-1 and 12 μg L-1 and the limit of detection is 0.011 μg L-1, the relative standard deviation (RSD) in five replicate determinations for 2 and 8 μg L-1 copper (Ⅱ) are 3.2% and 2.3%, respectively. Twenty ions do not interfere in the determination of copper (Ⅱ). The method has been applied satisfactorily to the determination of copper (Ⅱ) in freshwater samples (tap water and Yellow River water from Lijin, Shandong, China) and seawater samples (from the South China Sea), the recovery rates are 98.0%, 102.5% and 96.0%, respectively.

A level set based segmentation approach for point-sampled surfaces

Segmenting a complex 3D surface model into some visually meaningful sub-parts is one of the fundamental problems in digital geometry processing. In this paper, a novel segmentation approach of point-sampled surfaces is proposed, which is based on the level set evolution scheme. To segment the model so as to align the patch boundaries with high curvature zones, the driven speed function for the zero level set inside narrow band is defined by the extended curvature field, which approaches zero speed as the propagating front approaches high curvature zone. The effectiveness of the proposed approach is demonstrated by our ex- perimental results. Furthermore, two applications of model segmentation are illustrated, such as piecewise parameterization and local editing for point-sampled geometry.

Is the Chinese Renminbi Undervalued？ An Examination of the B-S Effect Using Diverse Datasets

In 2010, the debate over valuation of the Renminbi is again heating up and the Chinese currency has returned to appreciating against the dollar But is the Renminbi undervalued？ Drawing on the Balassa-Samuelson （B-S） effect on purchasing power parity, we conduct theoretical and empirical analyses of this issue. Theoretical analysis proves that a country＇s real exchange rate will appreciate with rising income, but the currencies of low-income countries tend to be undervalued. In order to avoid biased conclusions resulting from a single dataset or sampling method, we draw on three major publicly-available datasets to examine the B-S effect across 144 economies. Our results indicate that the degree of Renminbi misvaluation is highly dependent on the data source. Synthesizing analyses of diverse datasets, we estimate that the Renminbi was only undervalued by less than 8per cent in 2009. We conclude that China＇s external imbalance most probably results from deep-seated structural imbalances rather than Renminbi undervaluation.

Oil–water pre-separation with a novel axial hydrocyclone

A novel hydrocyclone with guide vanes, named as axial hydrocyclone(AHC), is designed to tackle the problem of oil–water separation faced by most mature oilfields. Optimal design of the AHC is carried out by using numerical methods. The effects of guide vanes, cone angle, tapered angle and overflow pipe on the oil–water separation are discussed in this paper. The results show that a double swirling flow is generated in the tapered section where oil–water separation occurs. Both the cylindrical and the tapered section have important influences on AHC performance. On the basis of single factor results, response surface methodology is employed to optimize the AHC design. The experimental results indicate that the novel AHC has an excellent performance for the oil–water separation.

Tracing Changes in the Microbial Community of a Hydrocarbon-Polluted Soil by Culture-Dependent Proteomics

Hydrocarbon contamination may affect the soil microbial community, in terms of both diversity and function. A laboratory experiment was set-up, with a semi-arid control soil and the same soil but artificially contaminated with diesel oil, to follow changes in the dominant species of the microbial community in the hydrocarbon-polluted soil via proteomics. Analysis of the proteins extracted from enriched cultures growing in Luria-Bertani （LB） media showed a change in the microbial community. The majority of the proteins were related to gIycolysis pathways, structural or protein synthesis. The results showed a relative increase in the complexity of the soil microbial community with hydrocarbon contamination, especially after 15 days of incubation. Species such as Ralstonia solanacearum, Synechococcus elongatus and different Clostridium sp. were adapted to contamination, not appearing in the control soil, although Bacillus sp. dominated the growing in LB in any of the treatments. We conclude that the identification of microbial species in soil extracts by culture-dependent proteomics is able to partially explain the changes in the diversity of the soil microbial community in hydrocarbon polluted semi-arid soils, but this information is much more limited than that provided by molecular methods.

Local Data Analysis for Eliminating End Restraint of Triaxial Specimen

A data processing method was proposed for eliminating the end restraint in triaxial tests of soil. A digital image processing method was used to calculate the local deformations and local stresses for any region on the surface of triaxial soil specimens. The principle and implementation of this digital image processing method were introduced as well as the calculation method for local mechanical properties of soil specimens. Comparisons were made between the test results calculated by the data from both the entire specimen and local regions, and it was found that the deformations were more uniform in the middle region compared with the entire specimen. In order to quantify the nonuniform characteristic of deformation, the non-uniformity coefficients of strain were defined and calculated. Traditional and end-lubricated triaxial tests were conducted under the same condition to investigate the effects of using local region data for deformation calculation on eliminating the end restraint of specimens. After the statistical analysis of all test results, it was concluded that for the tested soil specimen with the size of 39.1 mm × 80 ram, the utilization of the middle 35 mm region of traditional specimens in data processing had a better effect on eliminating end restraint compared with end lubrication. Furthermore, the local data analysis in this paper was validated through the comparisons with the test results from other researchers.

Persistence of Imidacloprid and β-Cyfluthrin Residue in Black Pepper （Piper Nigrum L.） under Malaysia Climatic Condition

Persistence behavior of imidacloprid and beta-cyfluthrin in black pepper was studied following application of formulation of Solomon at 0.6 （recommended dose） and 1.2 （double recommended dose） g a.i./ha for one pepper production cycle. The results also showed that the Solomon at 0.6 mL/L concentration significantly suppressed the pest infestation in pepper vines. Pepper vine treated with Solomon produce more berries compared to control and showed no phytotoxicity. Analytical procedure of Solomon active ingredient was validated prior to actual analysis. Satisfactory recoveries ranging between 87.6%-106.7% were obtained for the fortified pepper berries samples. Results showed low level of imidacloprid and beta-cyfluthrin residues in dried pepper berries ranging between 〈 0.01 mg/kg to 1.43 mg/kg and 〈 0.01 mg/kg to 1.612 mg/kg respectively. The half-life value period for imidacloprid were found to be 2.06 and 2.30 days and for beta-cyfluthrin, these values were observed to be 1.57 and 1.49 days respectively at recommended and double recommended dose. Imidacloprid and beta-cyfluthrin residue dissipated below the limit of quantification （LOQ） of 0.01 mg/kg after 7 and 9 days respectively at recommended and double recommended dose. Soil sample collected 15 days after the last spray did not show the present of Imidacloprid and beta-cyfluthrin residue at their detection limit of 0.01 mg/kg.

A new manufacture method of backfill samples in lab——Illustrated with a case study

The differences between the formation processes of lab backfill samples and field backfill were analysed. An improved sampling mold, containing an outer box shell and inner sampling mold, was put forward. The new and traditional test molds were applied to make subsequent-backfill samples of Yong-ping Copper Mine. The observation of mass fraction and theory analysis of settlement and distribution of tailing particles were carried out. The research results show that the magnitude of the strength of the backfill forming in new mold is lower than that of backfill forming in traditional mold, and the biggest gap amounts to 36%.

The Effects of Job Security, Features, Personal Values, and Recognition on Organizational Involvement

As extrinsic rewards become very limited under organizational retrenchments, organizations should rely heavily on other types of rewards, such as intrinsic rewards, to improve the performance of those employees who have been overwhelmed with a perception of job insecurity. This paper examines the impact of such perception, along with many other positive influencers such as enhancement in job features, recognition, and the personal values of those employees on the organizational involvement. The data analyzed were based on a sample of 34 employee respondents from a project based engineering and service company （identified as ABC Company in this paper） operating in the Middle East. The adopted research approach is basically a quantitative approach. The correlation and regression analysis tools have been used to explore this relationship. The results of this study suggest a generally unnoticed and disregarded resource that has the prime effect on improving and enhancing the organizational involvement, which is the recognition those employees receive from the management. This research suggests that recognition, as the top influencer, has a strong impact on organizational involvement/psychological attachment for the employees. The other factors that have proved to have the second degree influence on organizational involvement are enhancement in job features, increase in the job security level, and personal values.

Interpolation in R^2 with Minimum Value of the Uniform Norm of the Laplace Operator

Problems, which are studied in the paper, concern to theoretical aspects of interpolation theory. As is known, interpolation is one of the methods for approximate representation or recovery of functions on the basis of their given values at points of a grid. Interpolating functions can be chosen by many various ways. In the paper the authors are interested in interpolating functions, for which the Laplace operator, applied to them, has a minimal norm. The authors interpolate infinite bounded sequences at the knots of the square grid in Euclidian space. The considered problem is formulated as an extremal one. The main result of the paper is the theorem, in which certain estimates for the uniform norm of the Laplace operator applied to smooth interpolating functions of two real variables are established for the class of all bounded （in the corresponding discrete norm） interpolated sequences. Also connections of the considered interpolation problem with other problems and with embeddings of the Sobolev classes into the space of continuous functions are discussed. In the final part of the main section of the paper, the authors formulate some open problems in this area and sketch possible approaches to the search of solutions. In order to prove the main results, the authors use methods of classical mathematical analysis and the theory of polynomial splines of one variable with equidistant knots.

Improvement of saponification extraction method for fatty acids separation from geological samples

The conventional saponification method could result in lower recoveries and artificial changes of longchain fatty acids. The main reason is the error judgment of the intermediate layer suspended between the aqueous and organic layer during the liquid–liquid extraction process.This study shows that the intermediate layer consists of lots of medium- to long-chain carboxylic salts for their special physical and chemical properties. An improved saponification extraction method is also developed and the results show that the carboxylic salts distributed in the intermediate layer could be obtained completely, which greatly enhances the authenticity and accuracy of fatty acid analysis. Additionally, the possible reasons of formation of the intermediate layer are also discussed.

A Comparison between Neutron Activation Analysis and X-Ray Fluorescence Methods in Analyzing the Granite Samples

This study focused on the performance of where elements analysing techniques were used to detect the elements in granite stones. These techniques are NAA （neutron activation analysis） and XRF （X-ray fluorescence）. They were applied to detect the elements in samples which had been chosen from different areas of Pulua Penang in Malaysia collected by geophysics group which helped to describe and identify the elements found in the granite stone that were used in the study procedures to control the analytical results. The integration of both methods has enabled the researcher to determine 40 elements in the samples. The numbers of elements detected by XRF analysis method are 12 elements （Ar, K, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn）; while, the elements detected by NAA method have three folds of elements with XRF analysis method were 35 elements （Na, AI, Si, K, Ca, Sc,Ti, Mn, Fe, Co, Ga, Ce, As, Br, Rb, Zr, Sb, I, Cs, Ba, La, Nd, Sm, Eu,Tb, Dy, Yb, Lu, Hf, Ta, W, Au, Pa and Np）. Seven common elements were detected in both techniques： K, Sc, Ti, V, Mn, Fe and Co. Si has a higher concentration in NAA technique which is 331.8 ppm. Sc has a lower concentration in XRF technique which is 0.25 ppm. Nd has a lower concentration in NAA technique which is 3.09 - 10-5 ppm. Finally, it is found that the NAA is better to detect the elements than XRF.

Exploration of SDSS stellar database by AutoClass

AutoClass is an unsupervised Bayesian classification approach which seeks a maximum posterior probability classification for determining the optimal classes in large data sets. Using stellar photometric data from the Sloan Digital Sky Survey (SDSS) data release 7 (DR7), we utilize AutoClass to select non-stellar objects from this sample in order to build a pure stellar sample. For this purpose, the differences between PSF (point spread function) magnitudes and model magnitudes in five wavebands are taken as the input of AutoClass. Through clustering analysis of this sample by AutoClass, 617 non-stellar candidates are found. These candidates are identified by NED and SIMBAD databases. Most of the identified sources (13 from SIMBAD and 28 from NED respectively) are extragalactic sources (e.g., galaxies, HII, radio sources, infrared sources), some are peculiar stars (e.g., supernovas), and very few are normal stars. The extragalactic sources and peculiar stars of the identified objects occupy 94.1%. The result indicates that this method is an effective and robust clustering algorithm to find non-stellar objects and peculiar stars from the total stellar sample.

Application of Bayesian approach to hydrological frequency analysis

An existing Bayesian flood frequency analysis method is applied to quantile estimation for Pearson type three (P-III) probability distribution. The method couples prior and sample information under the framework of Bayesian formula, and the Markov Chain Monte Carlo (MCMC) sampling approach is used to estimate posterior distributions of parameters. Different from the original sampling algorithm (i.e. the important sampling) used in the existing approach, we use the adaptive metropolis (AM) sampling technique to generate a large number of parameter sets from Bayesian parameter posterior distributions in this paper. Consequently, the sampling distributions for quantiles or the hydrological design values are constructed. The sampling distributions of quantiles are estimated as the Bayesian method can provide not only various kinds of point estimators for quantiles, e.g. the expectation estimator, but also quantitative evaluation on uncertainties of these point estimators. Therefore, the Bayesian method brings more useful information to hydrological frequency analysis. As an example, the flood extreme sample series at a gauge are used to demonstrate the procedure of application.

Applications of the representative points in statistical simulations

The paper gives a new approach to statistical simulation and resampling by the use of numbertheoretic methods and representative points. Resempling techniques take samples from an approximate population. The bootstrap suggests to use a random sample to form an approximate population. We propose to construct some approximate population distribution by the use of two kinds of representative points, and samples are taken from these approximate distributions. The statistical inference is based on those samples. The statistical inference in this paper involves estimation of mean, variance, skewness, kurtosis, quantile and density of the population distribution. Our results show that the new method can significantly improve the results by the use of Monte Carlo methods.