提升食品检测准确率的方法

食品检测是保障食品安全的重要方式,通过食品检测能够及时发现食品存在的质量问题、防控问题食品流入市场。本文对提升食品检测准确率的方法进行了研究,对影响食品检验的检测准确率的因素进行了分析,提出一些提升食品检测准确率的方法。希望以此抛砖引玉,共同提升食品检测准确率。

Rutting influencing factors and prediction model for asphalt pavements based on the factor analysis method

To clarify the importance of various influencing factors on asphalt pavement rutting deformation and determine a screening method of model indicators,the data of the RIOHTrack full-scale track were examined using the factor analysis method(FAM).Taking the standard test pavement structure of RIOHTrack as an example,four rutting influencing factors from different aspects were determined through statistical analysis.Furthermore,the common influencing factors among the rutting influencing factors were studied based on FAM.Results show that the common factor can well characterize accumulative ESALs,center-point deflection,and temperature,besides humidity,which indicates that these three influencing factors can have an important impact on rutting.Moreover,an empirical rutting prediction model was established based on the selected influencing factors,which proved to exhibit high prediction accuracy.These analysis results demonstrate that the FAM is an effective screening method for rutting prediction model indicators,which provides a reference for the selection of independent model indicators in other rutting prediction model research when used in other areas and is of great significance for the prediction and control of rutting distress.

Impacts of Social and Demographic Factors on Residents' Subjective Well-being in Rural China

The objective of social development is to construct a harmonious society.In China,the key to a harmonious society is the happiness of more than 900 million farmers living in the rural areas.This study aimed to measure rural residents' subjective well-being(SWB) through the day reconstruction method,as well as to analyze SWB's influencing factors through a variety of statistical methods.The results showed that the average U index was 12.79%,indicating that respondents were unhappy 12.79% of the time.Twenty-seven percent of the population had a U index greater than 0,with the average value being 47%,indicating that these people were unhappy 47% of the time.The study also found that SWB varied according to the characteristics of the respondents.Logistic regression analysis showed that social and demographic factors,including age,education,county,household size,generation number,per capita income,migration status and social networking,which significantly affected rural residents' SWB.The size of the impact varied with the different factors.

Selection model of trip time for rural population

Referring to the 1 248 survey data of rural population in 14 provinces of China, the influencing factors of trip time choice were analyzed. Based on the basic theory of disaggregate model and its modelling method, nine grades were selected as the alternatives of trip time, the variables affecting time choice and the method getting their values were determined, and a multinomial logit (MNL) model was developed. Another 1 200 trip data of rural population were selected to testify the model's validity. The result shows that the maximum absolute error of each period between calculated value and statistic is 3.6%, so MNL model has high calculation accuracy.

Numerical simulation of the factors influencing dust in drilling tunnels:Its application

Gas-solid two-phase flow theory was used to predict dust distribution and movement at the working face of a mine.The software package FLUENT was used to numerically simulate dust motion and the results were compared to observed data.The simulation agrees with the data taken from an actual working face,which confirms the choice of mathematical model and numerical simulation method. Using the model we predict a set of conditions optimum for reducing dust concentrations at the mine working face.

Analyzing the Factors Affecting the Users＇ Success in Web Based Education： A Data Mining Approach

Corporations focus on web based education to train their employees ever more than before. Unlike traditional learning environments, web based education applications store large amount of data. This growing availability of data stimulated the emergence of a new field called educational data mining. In this study, the classification method is implemented on a data that is obtained from a company which uses web based education to train their employees. The authors＇ aim is to find out the most critical factors that influence the users＇ success. For the classification of the data, two decision tree algorithms, Classification and Regression Tree （CART） and Quick, Unbiased and Efficient Statistical Tree （QUEST） are applied. According to the results, assurance of a certificate at the end of the training is found to be the most critical factor that influences the users＇ success. Position, number of work years and the education level of the user, are also found as important factors.

Fault Feature Extraction of Rotating Machinery Based on Wavelet Transformation and Multi-resolution Analysis

This paper expounded in detail the principle of energy spectrum analysis based on discrete wavelet transformation and multiresolution analysis. In the aspect of feature extraction method study, with investigating the feature of impact factor in vibration signals and considering the non-placidity and non-linear of vibration diagnosis signals, the authors import wavelet analysis and fractal theory as the tools of faulty signal feature description. Experimental results proved the validity of this method. To some extent, this method provides a good approach of resolving the wholesome problem of fault feature symptom description.

Research on Incentive Mechanism of Virtual Community Knowledge Sharing

With the continuous development of Internet technology, the network has become an important part of people＇s lives, the emergence of virtual communities is promoting the deep interaction oflntemet users, but it is found that the virtual community ＂diving party＂ is more and more through investigation and literature research, The quantity and quality of knowledge sharing are declining. Therefore, this paper summarizes the behavior and influencing factors of knowledge sharing in virtual community through literature research and investigation and research. At the same time, through the research of incentive theory, the author has obtained the incentive method and content of knowledge sharing, and established the incentive mechanism. The bright spot is to perfect the theory of knowledge sharing while transforming theory into practice, and to provide suggestions for the development of incentive mechanism of virtual community.

Related factors and regional differences in energy consumption in China

This article used the Cluster analysis of statistical method to separate China＇s 30 provinces and municipalities into three categories according to their energy consumption discrepancies and characteristics from 1985 to 2007. The categories were high, moderate and low energy consumption areas and they had significant differences in energy consumption. Based on this classification, the authors analyzed the influencing factors of energy consumption in the three areas by means of panel data econometric model. The results showed that the influencing factors were obviously different. In order to support national goal of energy conservation and emission reduction, the energy measures and policies should be distinctly taken.

Closure technique for the hybrid girder cable stayed bridge of Edong Bridge

Based on Edong Yangtze River Bridge, which is the second longest hybrid girder cable stayed bridge with 926 m long main span, the influencing factors and crucial techniques of the main span closure method for long span hybrid girder cable stayed bridge are studied. After theoretical analysis, numerical evaluation and practical test, the loading assistant closure method is employed in Edong Yangtze River Bridge. The loading assistant closure method, with better thermal adaptability and less influence on bridge line and the forced status, can meet the requirements of the unstressed state control method. Based on the mentioned advantages, the loading assistant closure method is applicable to long span hybrid girder cable stayed bridges. The conclusion can provide a reference for the further design of the similar brid^es.

Research on Regional Industrial Solid Waste Comprehensive Utilization Ability Influencing Factors based on Panel Data

On the basis of panel data from 29 provinces and cities throughout the country in 2006-2010, a research is made on factors influencing regional industrial solid waste comprehensive utilization ability through a regression analysis method. Research result shows that a positive influence will generate on the comprehensive utilization ability of the industrial solid waste by three factors： regional industrial soldi waste treatment earning level, regional industrial soldi waste treatment investment level and regional industrial pollution treatment subsidy strength. And this thesis will propose suggestions from improving earning ability, enhartcing treatment investment and increasing government subsidy depending on result of empirical analysis.

Accelerating Life Test Scheme and Modeling Method for Machinegun

There is a pressing need for improving the current whole life shooting method in order to reduce ammunition consumption in the firearms lifetime test. The influencing factors, the characterization parameters and the correlation analysis result of lifetime were considered. Accelerating life test and measuring scheme for machinegun were designed systematically by applying such theoretical methods as accelerating test, uniform design and lifetime model. As result, it provides a more scientific and reasonable accelerating life test scheme and proposes methods on modeling lifetime, optimizing model and characterizing lifetime. The conclusion can be used in preparing accelerating life test scheme and lifetime model for machinegun.

Platinum nanowires catalyzed direct amidation of aldehydes and amines

Different from the conventional synthesis methods and substrates, we designed a brand new method for synthesizing amides with platinum nanowires as catalysts and tert-butylhydroperoxide(TBHP) as the oxidant. Influence of factors, such as the catalyst, solvents, and the reaction temperature, were studied to determine the optimal reaction conditions. In addition, we explored the substrate generality and observed excellent yields.