2015 Vol. 30, No. 3-4
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Through investigating the adding time and dosage of pectinase,the effect of pectinase treatment on methyl alcohol and main fusel oil content was studied.The result suggested that pectinase had no significant influence on the change of total sugar and alcohol content in the process of Hawthorn fruit wine fermentation.The total acid content of the Hawthorn fruit wine with pectinase treatment was higher than that without pectinase treatment.The curve of pectin content in the Hawthorn fruit wine fermentation,which was not treated by pectinase before fermentation,declined firstly and then stabilized above 2 g/L.The methanol content was increasing in the wine with pectinase treatment before fermentation,which was 5.7 times higher than the wine without pectinase treatment(control sample),but changing slightly after fermentation.Different pectinase treatment time had no obvious effect on the main fusel oil content.The methanol content increased with increasing dosage of pectinase adding before or after fermentation,and changed slowly when the dosage was more than 0.1 g/L.Besides,effects of pectinase treatment at different timing on main fusel oil content were not obvious.
Using fresh garlic as raw material to ferment black garlic naturally,volatile flavor compounds from black garlic were collected using solid-phase microextraction (SPME) and identified by GC-MS.The components were compared with the volatile components of fresh garlic.The results showed that 14 kinds of volatile flavor compounds content in black garlic were higher.The main compounds extracted from black garlic were 2,2-dimethyl-1,3-dithiane(41.26%,fragrant),diallyl sulfide (22.10%,light fragrant),diallyl disulphide(9.67%,strong irritant),and so on.Compared with fresh garlic,the excitant material content in black garlic such as diallyl disulphide decreased significantly while thiamethoxam alkanes with aromas material increased.At the same time,pyrazine flavoring substances also generated in black garlic which were nonexistent in the fresh garlic,and gave the black garlic special pleasant aroma.
Using steamed bread as the research object,the quality changes of the vacuum packing steamed bread during storage at indoor temperature were studied by investigating the changes of moisture,TPA,proton signal and protein secondary structure of the vacuum packing steamed bread.The results showed that the moisture and TPA index of the vacuum packing steamed bread during storage at indoor temperature changed slightly.Three states of water (bound water,weak bound water and free water) had no obvious changes.The protein secondary structure (α-helix,β-sheet,β-turn and random coil) of steamed bread changed obviously,but only α-helix of its centre had relatively obvious change.
Using Pu'er tea as raw material,filter paper diffusion method was adopted to study the antibacterial activity of petroleum ether,chloroform,ethyl acetate,n-butyl alcohol and residues after extraction from Pu'er tea 95% alcohol extraction in vitro on S.aureus and E.coli.The antibacterial activity stability of ethyl acetate extracts was also studied.The results indicated that the above four Pu'er tea extracts had certain degree of inhibitory effect against S.aureus and E.coli.Among them,ethyl acetate extracts on S.aureus and E.coli inhibitory effect was the best,and bacteriostatic ring diameters of two kinds of subjects were (31.88±0.24) mm and (22.81±0.31) mm, MIC were 0.47 mg/mL and 0.35 mg/mL respectively.The ethyl acetate extracts stability experimental results showed that ethyl acetate extracts was very stable antibacterial activity to temperature and UV irradiation,but the acid and alkaline influenced its antimicrobial activity obviously,antibacterial activity became poor gradually with pH increasing.
An evaluation method for uncertainty in measuring ochratoxin A(OTA) in cereal grains with HPLC was established.Standard uncertainty and expanded uncertainty of the components in the process of the determination were calculated,an evaluation and comparison on the sources of uncertainty and the relative contribution were made. The results showed that the sources of the determination result uncertainty could be attributed to uncertainty of calibration, weighting sample, volume, recovery and testing by instrument. Preparing standard solution of the uncertainty of calibration accounted for the largest proportion of the uncertainty, and the uncertainty of volume accounted for the minimum. The expanded uncertainty was 0.476 μg/kg (coverage factor k=2) when the content of OTA was 3.17 μg/kg in cereal grains.Therefore, testing personnel should prepare standard solution strictly in accordance with the specification, at the same time, hold good critical control points of pretreatment process steps such as extraction, purification, elution and so on, in order to control the uncertainty of the determination results in an acceptable range.
Applying regular morphology combined with the technology of ITS sequence analysis, the identification and phylogenetic analysis of the 4 cultivated strains and 5 wild morel isolates mainly collected from Sichuan province and Chongqing municipality were carried out. The study followed the sequence identification program required by data bank of multilocus sequence typing(MLST). The phylogenetic tree was constructed with reliable sequences obtained from BLAST one-by-one comparison. The results suggested that the cultivated morel varieties were identified as Morchella importuna, M.sextelata and M.septimelata. In addition,5 wild isolates were identified as M.elata and M.importuna,respectively.
Colloidal gold immune chromatography strip was prepared by using C-reactive protein monoclonal antibody pairs to label and coat.The color card with obvious gradient color was made by serum calibration,and the coincidence rate,stability and precision of the strip and color card were detected,thus the C-reactive protein semiquantitative detecting was achieved.The results showed that this method had high repeatability,stability and precision.Compared with latex turbidimetry to detect 100 clinical serum parallelly,the two methods both met the coincidence rate of 98%.Semiquantitative C-reactive protein colloidal gold method was initially established,and it was easy in operation,clear in result and needed no special quxiliary device.
To the problems that the traditional primary quality evaluation system focuses on subjective factors with lacking of scientific evidence and quantitative analysis,an evaluation method of tobacco primary quality system based on ANP was proposed. In order to research the influence weight of the key process of tobacco primary processing, the ANP network model and the comparison judgment matrix were constructed, and the quality evaluation of the ranking results was made based on the weighted super matrix. The results showed that the effect of cylinder drying on the primary quality was the most significant. In production, the quality of the tobacco primary was improved obviously through strengthening the parameters optimization and stability control of cylinder drying process.These showed that the evaluation method of tobacco primary quality based on ANP could effectively improve the control accuracy of tobacco primary processing and the control ability of process quality, and provide the theoretical basis for determining the optimum technological conditions and accurate technological parameters for tobacco primary processing.
To optimize the PID control of tobacco primary processing and increase the instantaneous precision of shredded tobacco blending,an intelligent PID control model FNN-PID based on fuzzy neural network was proposed. The intelligent fuzzy quantization was conducted according to the demand of shredded tobacco blending ratio and production dynamic data. By comparing the expert knowledge base, and combining with the analysis of intelligent reasoning machine, the ratio adjustment parameter of shredded tobacco blending was decided to take part in the feedback PID control. The practical application results showed that by using this model to control the relative parameters, the instantaneous accuracy was improved significantly, and the system fluctuation was reduced, and consequently the processing requirements of high grade cigarette could be met.
In order to improve the application characteristics of microwave expanded cut stem blended in cigarette, a research was developed on analyzing the tendency of cigarette critical-to-quality characteristic which mainly include the physical property and sensory quality. The results of instrumental analysis and sensory evaluation turned out that:The draw resistance and hardness increased with the blending ration of microwave expanded cut stem. The weight of microwave expanded cut stem blended cigarette was 37 mg lighter when it had the same draw resistance and hardness.What's more,there was no significant difference in tobacco loss from cigarette end and the sensory quality of microwave expanded cut stem blended cigarette was better than the traditional one. The application of microwave expanded tobacco stem not only improved the sensory quality but also reduced the tobacco shred consumption of single-box, increasing the effects of reducing the tar and harmful components.
In order to research the effect of the filter containing capsule on the smoke composition index,the sweet-orange flavor capsule, filter and test cigarette were produced and the effect on tar,seven kinds of harmful components, cigarettes hazard evaluation index and cigarettes flavor characteristics of the filter containing sweet-orange flavor capsule were studied. The results showed that:the contents of tar and seven kinds of harmful components and cigarettes hazard evaluation index were reduced by the filter containing sweet-orange flavor capsule; the filter containing sweet-orange flavor capsule made a cigarette with two different flavor and taste characteristics and could alter the functional properties of cigarettes; after the capsule was broken,the flue-cured cigarette was made into the foreign-flavor cigarette with fresh-sweet flavor, sweet-orange flavor,and the flavor of smoke was harmonious.
In order to observe the effect of ventilation on cigarette physical and chemical properties, blended type and Virginia type cigarettes were made by online laser punching equipment. The results showed that ventilation rate of the two types of cigarettes was positively related with cigarette weight, and negatively related with cigarette resistance. The higher the ventilation rate was, the more the filter ventilation rate contributed to the total ventilation rate. The two types of cigarettes ventilation rate and filter ventilation rate had negative correlation with the release of nicotine, tar and carbon monoxide. Carbon monoxide was most affected, followed by tar, and nicotine was least affected. Once the cigarette properties were fixed, ventilation rate could be calculated firstly,then through adjusting the laser perforation parameters online, cigarette design demands could be met.
Through the single factor test,the response surface methodology and the absolute difference analysis method, the effect of the factors such as mounting position of the liquid level meter,the high and low level detection position of the liquid level meter,the compensation steam valve opening and closing point were investigated based on the comprehensive evaluation which were guided by the qualification rate of the stem washing temperature. The results showed that:When the mounting position of the liquid level meter was 34 cm,the low level detection position was 28 cm,the high level detection position was 38 cm,the maximal prediction value of the qualification rate of the stem washing temperature was 94.996%.When the temperature was less than 47.5℃, the opening of the compensation steam valve was 100%, which was gradually reduced with the increase of the water temperature; when the water temperature was more than 52.5℃, the opening of the compensation steam valve was closed. Through the program optimization of the liquid level detection,the compensation steam valve opening and closing point,the PID control program of the stem washing machine of YSG-8AF realized the automatic control of adding water and increasing temperature, the qualification rate of the stem washing temperature was increased from 79.85% to 99.92%.
In order to achieve the non-contact measurement of cigarette packing size, a size measuring method based on dual structured light was proposed.The dual structured light which crossed with a certain angle was used to scan the cigarette packing.The CCD camera was used to obtain reflection images of structured light in each rotation angle on cigarette packing.According to the conversion relationship between world coordinate system, structured light coordinate system and image coordinate system, the surface characteristics of the case was calculated from the deformation feature of structured light.Then, the size of the circumscribed cuboid from 3D point cloud was calculated.The experimental results showed that the measuring accuracy and the standard deviation of the method could meet the actual demand for testing,improving the measurement efficiency and accuracy effectively,providing an effective method of automatic measurement for cigarette packing size measurement.
In view of the drawbacks that internal operations of present database are mostly opaque,which likely causes confidential information leakage and resource abuse,a set of database audit system was proposed.The bypass to monitor was adopted in the system,through traffic grab to the specified port number on the server in the same LAN,network packets could be obtained.And then these captured network packets were analyzed,finally the analyzed audit information would backup to the secure database in a timely manner for search and analysis.The system could effectively ensure the security of database by monitoring the external users access to the database operation,recording operation behavior,and timely feeding back to the auditor controlling the database system security status in real time.The test results showed that the system had good character of effectiveness and real-time.
To solve the problem that the AVS video decoding scheme in present digital television monitoring system was rigid which caused difficulty in change and upgrading and so on, the AVS video C++ class player was designed based on FFMpeg codec library and DirectX platform. The design adopted the multi-thread database queue technology to share data, and synchronized to the audio play clock by controlling the video playback speed to ensure the smooth play of audio and video. The test result showed that the video player was supporting most media formats, less dependent and easy to expand,and it had a certain market prospects.
In view of the high cost and poor dynamic traffic conditions of traditional navigation system,the intelligent navigation system based on Android was presented.The system adopted C/S structure,and used the Baidu map Android SDK to develop the client.The server provided services to the client in the form of WebService.The test results showed that the system had a good user experience,convenience in operation,completeness in function,stablity in performance,and could meet a variety of travel navigation requirements of different users.
Aimed at the problem that automatic identification method for the cloud categories was less at present, a new method of cloud classification based on sparse representation of overcomplete dictionary was proposed. The method used different cloud types samples to establish an adaptive overcomplete dictionary, extracted dictionary features and designed sparse classifier to determine the type of cloud.The simulation analysis results showed that the classification accuracy of Ca,Cs&Cd,As&Ac,Ns&Cu,Cb were 100%, 63.5%, 90.3%, 94.1%, 98.2%, respectively.The overall classification accuracy was 89.2%. The classification accuracy was higher than the support vector machine classifier and the traditional sparse representation classifier.
For the current virtual machine migration algorithm is likely to cause physical node load imbalance,high energy consumption,SLA violation rate and other issues,a new cloud computing based online migration algorithm was proposed.An online migration algorithm model and virtual machine loads assessment vector were built,according to the CPU utilization,memory utilization and bandwidth utilization for each physical node to determine migration timing, source physical nodes which needed to migrate and the target physical nodes.The simulation of environmental testing showed that the proposed algorithm in a virtual machine live migration could greatly improve load balancing of the physical nodes,and meanwhile reduce the SLA violation rate and cloud computing data center power consumption to a minimum.
Based on new characters of embedded hybrid real-time transaction concurrency control,a hybrid concurrency control algorithm,namely mixed concurrency control-CCCP(MCC-CCCP),was proposed by adding substitution and compensation.Conflict was divided into the intra-class and inter-class in the algorithm.ET-CCCP protocol solved the intra-class conflict of hard real-time transaction,while CCCP protocol solved the intra-class conflict of soft real-time transaction.The LC-CCCP algorithm was designed to resolve the inter-class conflicts by comparing to select the least number of alternative involved in the concurrency control and taking some compensation measures to reduce the number of conflicts.Simulation experiments showed that the hybrid algorithm decreased the rate of restart and transaction miss, which had certain advantages.
Aimed at the security defect of group key agreement protocol for mobile environment proposed by J.L.Tsai,the protocol was improved by using the digital signature technology.That is,some serial numbers were inserted in the digital signatures so as to identify the signatures and the order of the group keys to be generated,and the serial numbers were used as part of public information to verify the digital signatures.So the freshness of messages sent by the mobile users or the powerful node could be checked.According to the security analysis,it is found that the improved protocol not only had the old security properties,but also could resist against impersonation attack or forgery attack.
The performance difference of trans-critical CO2 throttle valve cycle, trans-critical CO2 internal heat exchanger cycle and trans-critical CO2 expander cycle was investigated by theoretical analysis and numerical simulation. The results showed that:under the same conditions, the cooling capacity of internal heat exchanger cycle was the biggest and throttle valve cycle was the smallest; the power dissipation of internal heat exchanger cycle was the biggest and the expander cycle was smallest; the COP of expander cycle was the biggest and throttle valve cycle was the smallest; the compressor discharge temperature of internal heat exchanger cycle was higher than throttle valve cycle and expander cycle.To sum up,the COP of throttle valve cycle was the smallest. Internal heat exchanger cycle could improve the system cooling capacity, but it also increased the compressor discharge temperature. Expander cycle could reduce system power dissipation effectively, and could more significantly improve system COP, it had the better performance.
According to the related theories of kinematics,gas dynamics and gas thermodynamics,the kinematical equations for vibration of the air spring,and the differential equation of the gas flow rate through the damping hole air spring through the damping hole gas were deduced firstly.Then,the mathematical model of dynamic stiffness and damping was established. The mathematical model showed that the dynamic stiffness and damping of the air spring were related to the parameters of air chamber volume, damping hole diameter, initial spring pressure,equivalent working area and cross-sectional area of main air chamber,at the same time they changed with external vibration frequency.Finally,taking the effect of damping hole diameter on dynamic performance of air spring as the example,the model was confirmed that it was effective and practical.
According to the unified strength theory and Mohr coulomb theory,the function of soil was deduced considering the intermediate principal stress,and the soil collapse probability at the tunnel hole was derivated from Matlab program based on design point method in order to analyze the influence of intermediate principal stress made on reliability of soil.The results showed that:firstly,considering that effect of intermediate principal stress could reduce the soil collapse probability at the tunnel hole and give the potential of material into full play,the project expense could be saved; secondly,when b=0 or t=0 or t=1,the probability value of soil collapse was equal to the value under the circumstance of taking no account of the intermediate principal stress,at the meantime,the value could be the maximum one; thirdly,the soil collapse probability would change over the numerical value of b and t,generally speaking, the probability would decrease and then increase with the rise of the numerical value of t,while the probability would decrease with the rise of the numerical value of b,therefore the value of b and t should be considered carefully,which had important significance for accurate evaluation of tunnel stability.
Aiming at the problems existed in the lead-acid battery,using voltage feedback loop and current feedback loop,the design of small and medium size electrical vehicle portable intelligent charger based on PIC16F873A and UC3846N was introduced to achieve the four-stage charging process.By testing the main board,the parameter characteristics showed that this charger could achieve fast charging with constant current and parameter real time monitoring,and realize the functions of over-heat protection, reverse polarity protection, over-voltage/current protection required above and it was low in weight, small in size and portable.
In order to solve the problem in weak current signal detection technology that the interference of background noise,circuit noise and component noise is stronger than signal itself,a weak current low noise amplifier application circuit was designed.The model improved T-type I/V conversion circuit by adopting high precision and small resistance value feed back resistance and high performance operational amplifier AD795,set up preamplifier circuit by high performance discrete elements and designed phrase-locked amplifier circuit based on modulation and demodulation principle.The simulation analysis showed that the circuit had higher noise suppression capability and stability and could meet the weak current measurement requirement of various sensors.
Aiming at synchronization problem of a new six-dimensional Duffing-Lu hyper-chaotic system, a new controller was designed through two different methods of synchronization control and non-synchronization control based on the Lyapunov stability theory. By choosing proper parameter (m) to set A+mI as positive definite matrix, synchronization was realized. Matlab numerical simulations results showed that both the methods could realize synchronization on the condition of the same parameter and same initial value, and the synchronization controller was proved to be simpler and could realize parameter identification.
For Stripping is the main factor of the efficiency of ammonia removal, and the traditional PID control can't get good control on sewage temperature, the sewage temperature fuzzy controller based on PLC was designed.The design adopted the timer interrupt block to implement two-dimensional fuzzy control of discrete domain,and adjusted steam addition amount by changing steam regulation value opening to realized precise control of sewage temperature.The experimental results showed that the practical control precision could reach 1.5℃, the design could effectively improve the efficiency of the deamination of Stripping and cost savings.
In view of electricity being wasted in the classrooms at university,the intelligent power saving and management system in colleges was designed based on LonWorks with the use of DDC controller and Kingview.The system could regulate and control the lighting in the classroom intelligently according to the number of students,illumination parameters,etc.At the same time,it realized the function of educational administration,anti-theft alarm,etc.The test results showed that the system was good in operation,easy to set up and ran stably,and achieved the purpose of saving electricity.
Selecting SO2 conversion ratio of metallurgical off-gases making acid as the research object, in order to solve the problem of over learning or slow network convergence speed existed in using single BP or RBF neural network to predict SO2 conversion ratio,the optimal mean square error weighted fusion algorithm was used to achieve fusion of two kinds of neural network and construct the better SO2 conversion ratio predication model. The simulation results showed that the optimal mean square error weighted fusion model avoided the lack of information of the single model,realized the complementation of information and effectively improved the SO2 conversion ratio predication precision.
The multidisciplinary research techniques in the study of articular cartilage tissue imaging were reviewed.The magnetic resonance imaging (MRI), microscopic MRI (μMRI), polarized light microscopy (PLM), Fourier-transform infrared imaging (FTIRI) and computer tomography (CT) were emphatically introduced.It was pointed out that each technique could probe an aspect of the tissue degradation complex mechanism with its own scientific principles.But in the current study of biomedical problems, the multidisciplinary approach is the best.
The auxiliary functions method was used to solve the generalized Boussinesq equations by transforming them into solving the algebraic equations.By the further application of the Maple software,ten exact travelling wave solutions of nonlinear generalized Boussinesq equation were gotten,which were abundant.Besides,the exact travelling wave solutions of the generalized KdV equations and the nonlinear coupled Schrodinger system will be gotten in this way.
Optimal dividend payments and capital injections of the piecewise-deterministic compound Poisson risk model were discussed.The objective of an insurance business under consideration was to maximize the discounted dividend payments minus the penalized discounted capital injections.By a method to determine numerically the solution to the HJB equation,the corresponding Hamilton-Jacobi-Bellman equation was derived.And the optimal dividend and strategy was the Threshold strategy.This conclusion made the risk model have more realistic and more practical significance.
Combining the global search ability of genetic algorithm and the local refinement ability of simulated annealing algorithm,a new kind of genetic simulated annealing algorithm was designed.The algorithm was used for solving a class of no differentiable NP-hard problem:Absolute value equations Ax-|x|=b.Numerical experiments showed that the algorithm could effectively overcome the shortcomings that the genetic algorithm was easy to premature and simulated annealing algorithm had low efficiency of operation.
Founded in 1986, bimonthly
Administered by:The Education Department Henan Province
Sponsored by:Zhengzhou University of Light Industry
Editor-in-chief:Wei Shizhong
Executive Editor-in-Chief:Zou Lin
Deputy Editor-in-Chief:Qu Shuanghong
Edited & published by:Editorial Department of Journal of Light Industry
CN 41-1437/TS
ISSN 2096-1553
Address:136 Science Avenue, Zhengzhou City, Henan Province, China
Postal Code:450001
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