2013 Vol. 28, No. 6
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2013, 28(6)
:1-5.
doi: 10.3969/j.issn.2095-476X.2013.06.001
Abstract:
Degradation of carotenoids in discarded tobacco leaves by biological and physical treatments was investigated. Biological treatment was to isolate a strain to effectively degrade β-carotene and this strain was identified a yeast Trichosporon. GC-MS analysis showed that this yeast could completely degrade β-carotene. The physical method was to treat discarded tobacco leaves by ozone. GC-MS analysis showed that the contents of carotenoid and chlorophyll increased during the processing time firstly, then decreased and became stable. Moreover, after ozone treatment, the contents of alcohols, esters and ketones in tobacco were raised, and the content of nicotine, neophytadiene and carbon stearic acid were reduced to mellow tobacco aroma and reduce irritancy.
Degradation of carotenoids in discarded tobacco leaves by biological and physical treatments was investigated. Biological treatment was to isolate a strain to effectively degrade β-carotene and this strain was identified a yeast Trichosporon. GC-MS analysis showed that this yeast could completely degrade β-carotene. The physical method was to treat discarded tobacco leaves by ozone. GC-MS analysis showed that the contents of carotenoid and chlorophyll increased during the processing time firstly, then decreased and became stable. Moreover, after ozone treatment, the contents of alcohols, esters and ketones in tobacco were raised, and the content of nicotine, neophytadiene and carbon stearic acid were reduced to mellow tobacco aroma and reduce irritancy.
2013, 28(6)
:6-8.
doi: 10.3969/j.issn.2095-476X.2013.06.002
Abstract:
In order to investigate the relationship between the sugar content and overall sensory coziness, sugar content and sensory coziness evaluation of 55 tobacco leaves was analyzed and verified. The data of sugar content and sensory coziness were analyzed by simple correlation analysis method and canonical correlation analysis method. The results were as follows: 1) Fructose, glucose, maltose and total sugar significantly or extremely significantly positively correlated with irritancy quality, while extremely significantly negatively correlatin with vigour, not significantly correlating with remaining taste and dryness; sucrose extremely significantly correlation with oral spike, while not significantly correlating with other sensory coziness qualities. 2) The specific influence degree order of correlation with overall sensory coziness was fructose > total sugar > glucose > maltose > sucrose; the specific influence degree order of correlation with sugar content was nasal stimulation > throat spine > vigour > oral spike > throat choking thorn > oral burr > residual > convergence > dryness > coating.
In order to investigate the relationship between the sugar content and overall sensory coziness, sugar content and sensory coziness evaluation of 55 tobacco leaves was analyzed and verified. The data of sugar content and sensory coziness were analyzed by simple correlation analysis method and canonical correlation analysis method. The results were as follows: 1) Fructose, glucose, maltose and total sugar significantly or extremely significantly positively correlated with irritancy quality, while extremely significantly negatively correlatin with vigour, not significantly correlating with remaining taste and dryness; sucrose extremely significantly correlation with oral spike, while not significantly correlating with other sensory coziness qualities. 2) The specific influence degree order of correlation with overall sensory coziness was fructose > total sugar > glucose > maltose > sucrose; the specific influence degree order of correlation with sugar content was nasal stimulation > throat spine > vigour > oral spike > throat choking thorn > oral burr > residual > convergence > dryness > coating.
2013, 28(6)
:9-13.
doi: 10.3969/j.issn.2095-476X.2013.06.003
Abstract:
In order to explore effects of cutting width of tobacco on 7 kinds of Hoffmann components(CO, NNK, NH3, HCN, BaP, crotonaldehyde, phenol) of mainstream smoke, the 7 kinds of Hoffmann components in mainstream smoke of cigarettes with different cutting width of tobacco were detected. The results indicated that: within the studied scope of the cutting width, with the increase of cutting width, CO, HCN and phenol in mainstream smoke decreased, NH3 increased, NNK and BaP first increased and then decreased, while crotonaldehyde and hazard index remained unchanged; reducing the cutting width was good to selectively decreasing NH3, BaP and crotonaldehyde, while improving the cutting width was conducive to the selective reduction of CO, HCN and phenol. To take tobacco quality and tobacco harm reduction into consideration, the best cutting width was 0.95 mm.
In order to explore effects of cutting width of tobacco on 7 kinds of Hoffmann components(CO, NNK, NH3, HCN, BaP, crotonaldehyde, phenol) of mainstream smoke, the 7 kinds of Hoffmann components in mainstream smoke of cigarettes with different cutting width of tobacco were detected. The results indicated that: within the studied scope of the cutting width, with the increase of cutting width, CO, HCN and phenol in mainstream smoke decreased, NH3 increased, NNK and BaP first increased and then decreased, while crotonaldehyde and hazard index remained unchanged; reducing the cutting width was good to selectively decreasing NH3, BaP and crotonaldehyde, while improving the cutting width was conducive to the selective reduction of CO, HCN and phenol. To take tobacco quality and tobacco harm reduction into consideration, the best cutting width was 0.95 mm.
2013, 28(6)
:14-17.
doi: 10.3969/j.issn.2095-476X.2013.06.004
Abstract:
The appearance quality, chemical component and sensory quality of main cultivars(Zhongyan 100 and Qinyan 96) in Sanmenxia tobacco-growing area were evaluated and compared. The results showed that Sanmenxia flue-cure tobacco leaves had good appearance quality, harmonious chemical components and significant full flavor style characteristic with prominent caramel sweetish aroma and supplemented by empyreumatique and spicy flavor. According to the tobacco quality target of Sanmenxia base unit of China Tobacco Jiangsu Industrial Co. Ltd., Zhongyan 100 better meets the demands than Qinyan 96.
The appearance quality, chemical component and sensory quality of main cultivars(Zhongyan 100 and Qinyan 96) in Sanmenxia tobacco-growing area were evaluated and compared. The results showed that Sanmenxia flue-cure tobacco leaves had good appearance quality, harmonious chemical components and significant full flavor style characteristic with prominent caramel sweetish aroma and supplemented by empyreumatique and spicy flavor. According to the tobacco quality target of Sanmenxia base unit of China Tobacco Jiangsu Industrial Co. Ltd., Zhongyan 100 better meets the demands than Qinyan 96.
2013, 28(6)
:18-21.
doi: 10.3969/j.issn.2095-476X.2013.06.005
Abstract:
The effects of preheat temperature, cyclic hot air temperature setting value and the P value of PID control were investigated in cigarette production based on the comprehensive evaluation which were guided by the Sigma level of cyclic temperature. The optimum conditions obtained by single factor and orthogonal methodology were as follows: preheat temperature and cyclic temperature setting value were its standard value, the P value of PID control was 500. Under these conditions, the temperature control program of WQ3318-SJ1525 was optimized, and the Sigma level of cycle temperature in leaf feeding increased from 2.0 to 3.94.
The effects of preheat temperature, cyclic hot air temperature setting value and the P value of PID control were investigated in cigarette production based on the comprehensive evaluation which were guided by the Sigma level of cyclic temperature. The optimum conditions obtained by single factor and orthogonal methodology were as follows: preheat temperature and cyclic temperature setting value were its standard value, the P value of PID control was 500. Under these conditions, the temperature control program of WQ3318-SJ1525 was optimized, and the Sigma level of cycle temperature in leaf feeding increased from 2.0 to 3.94.
2013, 28(6)
:22-26.
doi: 10.3969/j.issn.2095-476X.2013.06.006
Abstract:
In view of the problems of cold minced meat existing in the short shelf-life such as inconsistent quality and easiness to spoilage, the effects of different concentration of Pu'er tea extracts(PETs) on the shelf-life of minced pork were studied. The results showed that the addition of PETs(0.02%~0.12%) to the samples could not only significantly inhibit the growth of Enterobactteriaceae, Pseudomonas and the total aerobic bacterial, decrease the accumulation of the total volatile nitrogen base and thiobarbituric acid-reactive substances, but also increase the minced pork a* value and keep it's good sensory properties.
In view of the problems of cold minced meat existing in the short shelf-life such as inconsistent quality and easiness to spoilage, the effects of different concentration of Pu'er tea extracts(PETs) on the shelf-life of minced pork were studied. The results showed that the addition of PETs(0.02%~0.12%) to the samples could not only significantly inhibit the growth of Enterobactteriaceae, Pseudomonas and the total aerobic bacterial, decrease the accumulation of the total volatile nitrogen base and thiobarbituric acid-reactive substances, but also increase the minced pork a* value and keep it's good sensory properties.
2013, 28(6)
:27-31.
doi: 10.3969/j.issn.2095-476X.2013.06.007
Abstract:
The research achievements of pig bones treatment with enzymes and collagen polypeptide calcium synthesis, structure characterization and calcium chelating mechanism were reviewed. At present, most studies have focused on the synthesis of polypeptide calcium with enzymatic pig bones; the specific calcium chelating peptide characterization process simply reverse illation the mechanism to explore more complex by the product, but can not really reflect each process change of chelation. It needs further exploration and research.
The research achievements of pig bones treatment with enzymes and collagen polypeptide calcium synthesis, structure characterization and calcium chelating mechanism were reviewed. At present, most studies have focused on the synthesis of polypeptide calcium with enzymatic pig bones; the specific calcium chelating peptide characterization process simply reverse illation the mechanism to explore more complex by the product, but can not really reflect each process change of chelation. It needs further exploration and research.
2013, 28(6)
:32-34,47.
doi: 10.3969/j.issn.2095-476X.2013.06.008
Abstract:
In order to construct a recombinant expression plasmid which induced express purification measles virus(MV) N protein, the recombinant plamised of pET-32 a(+)/N amplified by PCR from MV N protein genes was inserted into expression vector pET-32 a(+), then it was transformed into E. coli BL21(DE3). The condition of time, temperature and concentration of IPTG were optimized. The results of SDSPAGE and Western blot tests showed that MV N protein molecular was 60 kD. The protein's purity was 90% after being purified by Ni-NTA and DEAE.
In order to construct a recombinant expression plasmid which induced express purification measles virus(MV) N protein, the recombinant plamised of pET-32 a(+)/N amplified by PCR from MV N protein genes was inserted into expression vector pET-32 a(+), then it was transformed into E. coli BL21(DE3). The condition of time, temperature and concentration of IPTG were optimized. The results of SDSPAGE and Western blot tests showed that MV N protein molecular was 60 kD. The protein's purity was 90% after being purified by Ni-NTA and DEAE.
2013, 28(6)
:35-38.
doi: 10.3969/j.issn.2095-476X.2013.06.009
Abstract:
As the green solvent, ionic liquids have certain toxicity, and it's incompleted degradation will cause huge damage to the environment. The study of ionic liquids toxicity to the higher plants focused on its impact on seed germination and seedling growth. The biodegradablity of imidazole and pyridine ionic liquids are not ideal; amino ionic liquids with biodegradability, low toxicity and high biocompatibility will become new research direction. Exploring the impact of ionic liquids on plant life cycle, designing readily biodegradable ionic liquids, screening dominant bacteria that have high degrading effect to ionic liquids through genetic engineering and building a comprehensive QSAR models of ionic liquid toxicity and biodegradability, will be the main studies in the future.
As the green solvent, ionic liquids have certain toxicity, and it's incompleted degradation will cause huge damage to the environment. The study of ionic liquids toxicity to the higher plants focused on its impact on seed germination and seedling growth. The biodegradablity of imidazole and pyridine ionic liquids are not ideal; amino ionic liquids with biodegradability, low toxicity and high biocompatibility will become new research direction. Exploring the impact of ionic liquids on plant life cycle, designing readily biodegradable ionic liquids, screening dominant bacteria that have high degrading effect to ionic liquids through genetic engineering and building a comprehensive QSAR models of ionic liquid toxicity and biodegradability, will be the main studies in the future.
2013, 28(6)
:39-43.
doi: 10.3969/j.issn.2095-476X.2013.06.010
Abstract:
The L-cysteine modified Au/Fe3O4 magnetic composite particles(LC-Au/Fe3O4) were synthesized and their adsorption properties for bovine serum albumin(BSA) were investigated. The obtained samples were characterized by UV-Vis spectrophotometer(UV-vis), X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FT-IR), scanning electron microscope(SEM), transmission electron microscope(TEM) and Zeta potential, respectively. The results showed that Fe3O4 of LC-Au/Fe3O4 has a spinel structure; its diameter was about 200 nm, and the particles showed good stability. The adsorption capacity of LCAu/Fe3O4 composite particles for BSA was 161.5 mg/g.
The L-cysteine modified Au/Fe3O4 magnetic composite particles(LC-Au/Fe3O4) were synthesized and their adsorption properties for bovine serum albumin(BSA) were investigated. The obtained samples were characterized by UV-Vis spectrophotometer(UV-vis), X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FT-IR), scanning electron microscope(SEM), transmission electron microscope(TEM) and Zeta potential, respectively. The results showed that Fe3O4 of LC-Au/Fe3O4 has a spinel structure; its diameter was about 200 nm, and the particles showed good stability. The adsorption capacity of LCAu/Fe3O4 composite particles for BSA was 161.5 mg/g.
2013, 28(6)
:44-47.
doi: 10.3969/j.issn.2095-476X.2013.06.011
Abstract:
The thermal property, mechanical property and rheological properties of poly(propylene carbonate) were studied by differential scanning calorimetry, thermo gravimetric analyzer, electronic tensile machine, melt flow rate instrument and capillary rheometer, respectively. The results showed that PPC had a lower glass transition temperature(Tg) and thermal decomposition temperature(Td), the glass transition temperature and temperatures of weight loss ratio at 5% were 31℃ and 211.3℃ respectively; the mechanical properties of PPC was low, the tensile strength and elongation at break were 7.50 MPa and 536.63% respectively, the melt flow rate increased with the temperature; PPC was pseudoplastic fluid, and the melt apparent viscosity decreased with increasing shear rate and temperature. Thus, the flowability of PPC melt could be improved by increasing temparature and shear rate during its preparation.
The thermal property, mechanical property and rheological properties of poly(propylene carbonate) were studied by differential scanning calorimetry, thermo gravimetric analyzer, electronic tensile machine, melt flow rate instrument and capillary rheometer, respectively. The results showed that PPC had a lower glass transition temperature(Tg) and thermal decomposition temperature(Td), the glass transition temperature and temperatures of weight loss ratio at 5% were 31℃ and 211.3℃ respectively; the mechanical properties of PPC was low, the tensile strength and elongation at break were 7.50 MPa and 536.63% respectively, the melt flow rate increased with the temperature; PPC was pseudoplastic fluid, and the melt apparent viscosity decreased with increasing shear rate and temperature. Thus, the flowability of PPC melt could be improved by increasing temparature and shear rate during its preparation.
2013, 28(6)
:48-52,85.
doi: 10.3969/j.issn.2095-476X.2013.06.012
Abstract:
This review presented the commonly used preparation methods for TiO2 and ZnO thin film of photo-anode of dye-densitized solar cells(DSSCs), such as sol-gel, hydrothermal synthesis, magnetron sputtering and electrochemical deposition, in addition with pulsed laser deposition method, metalorganic chemical vapor deposition, spray pyrolysis method and chemical precipitation process. The forecasts of the future developments of DSSCs will be preparation and optimization of semiconductor thin film, decreasing loss of electron conduction, composite of different semiconductor materials, optimizing energy structure and energy level matching of semiconductor and photosensitive dye, preparation of more compact and orderly nano-array optical anode materials and processes suitable for large-scale production.
This review presented the commonly used preparation methods for TiO2 and ZnO thin film of photo-anode of dye-densitized solar cells(DSSCs), such as sol-gel, hydrothermal synthesis, magnetron sputtering and electrochemical deposition, in addition with pulsed laser deposition method, metalorganic chemical vapor deposition, spray pyrolysis method and chemical precipitation process. The forecasts of the future developments of DSSCs will be preparation and optimization of semiconductor thin film, decreasing loss of electron conduction, composite of different semiconductor materials, optimizing energy structure and energy level matching of semiconductor and photosensitive dye, preparation of more compact and orderly nano-array optical anode materials and processes suitable for large-scale production.
2013, 28(6)
:53-57.
doi: 10.3969/j.issn.2095-476X.2013.06.013
Abstract:
Aiming at the problems that the tower crane often needs to transform arm length and the corresponding hoisting load varies frequently in the practical situation, a new parameterized calculation system of tower crane counterweight was developed, which was more practical, simple and convenient. The system which was based on the feature and working conditions, could build the tower crane main structure parametric model with Pro/E(the three dimensional design software), design and assemble automatically, according to the different length of the crane arm. It could transfer and invoke the data using VB cooperated with the Pro/E as the developing tool, so as to simplify the model and calculating process, which was proven to be correct and feasible by the examples.
Aiming at the problems that the tower crane often needs to transform arm length and the corresponding hoisting load varies frequently in the practical situation, a new parameterized calculation system of tower crane counterweight was developed, which was more practical, simple and convenient. The system which was based on the feature and working conditions, could build the tower crane main structure parametric model with Pro/E(the three dimensional design software), design and assemble automatically, according to the different length of the crane arm. It could transfer and invoke the data using VB cooperated with the Pro/E as the developing tool, so as to simplify the model and calculating process, which was proven to be correct and feasible by the examples.
2013, 28(6)
:58-62,76.
doi: 10.3969/j.issn.2095-476X.2013.06.014
Abstract:
In order to investigate the static behavior of SHS(square hollow section) X-joints under in-plane bending, geometry model and non-linear finite element analysis were carried out using ABAQUS software. Combining with verifying experiment, the failure mode, deformation process and ultimate capacity of SHS Xjoints were investigated, the effect of joint action between axial force and bending mement on the ultimate bearing capacity was also discussed. The results showed that, under in-plane bending, tension side of chord protruded, compression side sunk, and the welds in tension side of brace failed. Node chord entered a plastic phrase and finally the sample failed due to large plastic deformation. The ultimate capacity increased remarkably as β value increasd. Under the joint action between axial force and bending mement, the ultimate bearing capacity decreased.
In order to investigate the static behavior of SHS(square hollow section) X-joints under in-plane bending, geometry model and non-linear finite element analysis were carried out using ABAQUS software. Combining with verifying experiment, the failure mode, deformation process and ultimate capacity of SHS Xjoints were investigated, the effect of joint action between axial force and bending mement on the ultimate bearing capacity was also discussed. The results showed that, under in-plane bending, tension side of chord protruded, compression side sunk, and the welds in tension side of brace failed. Node chord entered a plastic phrase and finally the sample failed due to large plastic deformation. The ultimate capacity increased remarkably as β value increasd. Under the joint action between axial force and bending mement, the ultimate bearing capacity decreased.
2013, 28(6)
:63-66.
doi: 10.3969/j.issn.2095-476X.2013.06.015
Abstract:
In order to enhance the reliability of spaceborne equipment, structural design was made for the spaceborne cabinet based on the characters of spacecraft products. Adopting splicing enclosure, built-in 9 shielding box, it's built-in one print. Mechanical analysis of shock response spectrum and random vibration at the design phase were carried out. The results showed that the strength of the equipment was sufficient, without crack and fracture, the structural form was validated reasonable and the structural strength was validated reliable through mechanical experiments.
In order to enhance the reliability of spaceborne equipment, structural design was made for the spaceborne cabinet based on the characters of spacecraft products. Adopting splicing enclosure, built-in 9 shielding box, it's built-in one print. Mechanical analysis of shock response spectrum and random vibration at the design phase were carried out. The results showed that the strength of the equipment was sufficient, without crack and fracture, the structural form was validated reasonable and the structural strength was validated reliable through mechanical experiments.
2013, 28(6)
:67-72.
doi: 10.3969/j.issn.2095-476X.2013.06.016
Abstract:
A new type of 3-RRS parallel robot kinematics analysis method was proposed. Based on the screw theory, a 3-RRS parallel robot kinematics and anti-helix spiral model was established, obtaining the freedom of movement through the model analysis and Kutzbach Grubler calculated results, deriving a parallel position of the robot inverse solution models. Using Newton's iterative method of simulation software Matlab, the first positive solution and then inverse solution and then inverse solution after the first positive solution were calculated to verify the numerical accuracy. The 3-RRS method also applied to other parallel robots, and had application value.
A new type of 3-RRS parallel robot kinematics analysis method was proposed. Based on the screw theory, a 3-RRS parallel robot kinematics and anti-helix spiral model was established, obtaining the freedom of movement through the model analysis and Kutzbach Grubler calculated results, deriving a parallel position of the robot inverse solution models. Using Newton's iterative method of simulation software Matlab, the first positive solution and then inverse solution and then inverse solution after the first positive solution were calculated to verify the numerical accuracy. The 3-RRS method also applied to other parallel robots, and had application value.
Grey relational analysis on strength loss rate in freeze-thaw cycles of polypropylene fiber concrete
2013, 28(6)
:73-76.
doi: 10.3969/j.issn.2095-476X.2013.06.017
Abstract:
Using the grey relational analysis of grey system theory, the correlation of four main parameters of the effect strength loss rate of polypropylene fiber concrete on freeze-thaw cycles: water-cement ratio, volume fraction of fiber, fly ash content, and superplasticizer content was analyzed based on literature, and using the grey prediction model, the GM(1, N) equation of the strength loss rate of polypropylene fiber concrete in freeze-thaw cycles was established. The results showed that influencing factors of the strength loss rate of polypropylene fiber concrete in freeze-thaw cycles were as follows: water-cement ratio > superplasticizer content > fly ash content > volume fraction of fiber. The results of grey forecasting model GM(1, 5) showed good agreement with the experimental results. It was shown that could effectively predict the strength loss rate of polypropylene fiber concrete in freeze-thaw cycles by using the method of grey relational analysis.
Using the grey relational analysis of grey system theory, the correlation of four main parameters of the effect strength loss rate of polypropylene fiber concrete on freeze-thaw cycles: water-cement ratio, volume fraction of fiber, fly ash content, and superplasticizer content was analyzed based on literature, and using the grey prediction model, the GM(1, N) equation of the strength loss rate of polypropylene fiber concrete in freeze-thaw cycles was established. The results showed that influencing factors of the strength loss rate of polypropylene fiber concrete in freeze-thaw cycles were as follows: water-cement ratio > superplasticizer content > fly ash content > volume fraction of fiber. The results of grey forecasting model GM(1, 5) showed good agreement with the experimental results. It was shown that could effectively predict the strength loss rate of polypropylene fiber concrete in freeze-thaw cycles by using the method of grey relational analysis.
2013, 28(6)
:77-80.
doi: 10.3969/j.issn.2095-476X.2013.06.018
Abstract:
Based on the study of the traditional multi-robot path planning, an improved adaptive artificial potential field method was proposed. In this method, the local minimum problem of the traditional artificial potential field could be solved by setting the virtual target point for mobile robot to escape local minimum. At the same time, according to the task and speed of the robot, it used the adaptive priority strategy to realize the adaptive obstacle avoidance of the robot. The results of the simulation proved the effectiveness and feasibility of this method.
Based on the study of the traditional multi-robot path planning, an improved adaptive artificial potential field method was proposed. In this method, the local minimum problem of the traditional artificial potential field could be solved by setting the virtual target point for mobile robot to escape local minimum. At the same time, according to the task and speed of the robot, it used the adaptive priority strategy to realize the adaptive obstacle avoidance of the robot. The results of the simulation proved the effectiveness and feasibility of this method.
2013, 28(6)
:81-85.
doi: 10.3969/j.issn.2095-476X.2013.06.019
Abstract:
Aiming at the problem that principal component analysis(PCA) leads to a large amount of calculation in solving high rank-matrix and the modular two-dimensional principle component analysis(2DPCA) is still large in feature calculation and a certain correlation still exists in feature extraction, a method fusing the Modular 2DPCA with PCA was put forward. The method extracted feature from sub-image using M2DPCA, and re-formed a new matrix according to the order of sub-images of each image, then PCA was carried out on the new matrix. The experimental results in ORL human face database showed that the correlation among feature parameters was removed to a certain extent and it also greatly reduced the dimension of features.
Aiming at the problem that principal component analysis(PCA) leads to a large amount of calculation in solving high rank-matrix and the modular two-dimensional principle component analysis(2DPCA) is still large in feature calculation and a certain correlation still exists in feature extraction, a method fusing the Modular 2DPCA with PCA was put forward. The method extracted feature from sub-image using M2DPCA, and re-formed a new matrix according to the order of sub-images of each image, then PCA was carried out on the new matrix. The experimental results in ORL human face database showed that the correlation among feature parameters was removed to a certain extent and it also greatly reduced the dimension of features.
2013, 28(6)
:86-89,101.
doi: 10.3969/j.issn.2095-476X.2013.06.020
Abstract:
In order to meet the flexible access requirements between internal and external enterprise network, the improved Internet connection share scheme based on RRAS and NAT was designed. The simulation of the company network based on VMware virtual machine was carried out, and Internet access share of host and mobile terminal under the Dr. COM broadband authentication environment was successfully realized. Compared with traditional network access scheme, without purchasing dedicated hardware routers, the improved scheme has some advantages, such as the lower cost, the strong scalability of hardware and software, the flexible networking, etc, which was especially suitable for small and medium enterprises. This scheme provided the beneficial reference about studying Internet access for engineering and technical personnel.
In order to meet the flexible access requirements between internal and external enterprise network, the improved Internet connection share scheme based on RRAS and NAT was designed. The simulation of the company network based on VMware virtual machine was carried out, and Internet access share of host and mobile terminal under the Dr. COM broadband authentication environment was successfully realized. Compared with traditional network access scheme, without purchasing dedicated hardware routers, the improved scheme has some advantages, such as the lower cost, the strong scalability of hardware and software, the flexible networking, etc, which was especially suitable for small and medium enterprises. This scheme provided the beneficial reference about studying Internet access for engineering and technical personnel.
2013, 28(6)
:90-94.
doi: 10.3969/j.issn.2095-476X.2013.06.021
Abstract:
In ultra high voltage direct current(UHVDC) transmission system, in order to realize the function of the reactive power control to mitigate the harms of the harmonics produced by the converters to the system and the primary equipments, then to balance the reactive power exchanged between the AC and DC systems. Taking Yunnan-Guangdong ±800 kV UHVDC transmission project as an example, the voltage control, reactive power control and harmonic performance control for the DC filter groups switching was analyzed, and certain strategies to optimize the control logic of the DC filter groups were presented: pole control system for the station control system of the reference voltage was changed to the current voltage, at the same time increase a logic judgement that used to determine each pole whether effective unlocked, in order to eliminate filter group reactive power values and avoid excessive input filter system. This optimization strategy can fully solve the problems of station control in Yunnan-Guangdong project and have good reference value for the following UHVDC transmission project.
In ultra high voltage direct current(UHVDC) transmission system, in order to realize the function of the reactive power control to mitigate the harms of the harmonics produced by the converters to the system and the primary equipments, then to balance the reactive power exchanged between the AC and DC systems. Taking Yunnan-Guangdong ±800 kV UHVDC transmission project as an example, the voltage control, reactive power control and harmonic performance control for the DC filter groups switching was analyzed, and certain strategies to optimize the control logic of the DC filter groups were presented: pole control system for the station control system of the reference voltage was changed to the current voltage, at the same time increase a logic judgement that used to determine each pole whether effective unlocked, in order to eliminate filter group reactive power values and avoid excessive input filter system. This optimization strategy can fully solve the problems of station control in Yunnan-Guangdong project and have good reference value for the following UHVDC transmission project.
2013, 28(6)
:95-97,108.
doi: 10.3969/j.issn.2095-476X.2013.06.022
Abstract:
The motor speed measuring system based on incremental photoelectric encoder was designed using photoelectric encoder as the component for motor rotating speed. In this system, the output pulse of photoelectric encoder was reshaped by Schmitt triggers, then MCU gathered the signal and calculated the rotating speed value, the motor rotating speed and direction were displayed by the LCD, measurement cycles were set by keyboard and speed measurement algorithm used M/T method. The measurement system had the characteristics of high precision and real-time display, suitable for motor speed-measuring at runtime with smaller vibration.
The motor speed measuring system based on incremental photoelectric encoder was designed using photoelectric encoder as the component for motor rotating speed. In this system, the output pulse of photoelectric encoder was reshaped by Schmitt triggers, then MCU gathered the signal and calculated the rotating speed value, the motor rotating speed and direction were displayed by the LCD, measurement cycles were set by keyboard and speed measurement algorithm used M/T method. The measurement system had the characteristics of high precision and real-time display, suitable for motor speed-measuring at runtime with smaller vibration.
2013, 28(6)
:98-101.
doi: 10.3969/j.issn.2095-476X.2013.06.023
Abstract:
Taking the ATmega64 chip as the core of the circuit, the DC power supply aging monitoring system was designed. The system developed platform using industrial tablet computer as the main control machine, the functional unit of modular structure, driven by the RS845 interface bus and each functional unit to realize acquisition and monitoring of various parameters of the aging products. The practical application showed that the system had the advantages of good control effect, high reliability, flexible control.
Taking the ATmega64 chip as the core of the circuit, the DC power supply aging monitoring system was designed. The system developed platform using industrial tablet computer as the main control machine, the functional unit of modular structure, driven by the RS845 interface bus and each functional unit to realize acquisition and monitoring of various parameters of the aging products. The practical application showed that the system had the advantages of good control effect, high reliability, flexible control.
2013, 28(6)
:102-104.
doi: 10.3969/j.issn.2095-476X.2013.06.024
Abstract:
Aiming at the problem of generalized projective synchronization of discrete time-delayed different structure chaotic systems, based on Lyapunov stability theory, the conclusion was obtained that discrete time-delayed different structure chaotic systems were projective synchronization under the case selection of appropriate control law. Numerical simulation examples of chaotic system verified the effectiveness of the propsed method.
Aiming at the problem of generalized projective synchronization of discrete time-delayed different structure chaotic systems, based on Lyapunov stability theory, the conclusion was obtained that discrete time-delayed different structure chaotic systems were projective synchronization under the case selection of appropriate control law. Numerical simulation examples of chaotic system verified the effectiveness of the propsed method.
2013, 28(6)
:105-108.
doi: 10.3969/j.issn.2095-476X.2013.06.025
Abstract:
According to the propagation characteristics of hand foot and mouth disease, a continuous mathematical model of the spread of the disease was established. Its stability was also analyzed, and the control or continuous condition of the disease were obtained. Based on the obtained data, the numerical simulation was carried out according to the model. It illustrated the correctness of propagation model of the disease.
According to the propagation characteristics of hand foot and mouth disease, a continuous mathematical model of the spread of the disease was established. Its stability was also analyzed, and the control or continuous condition of the disease were obtained. Based on the obtained data, the numerical simulation was carried out according to the model. It illustrated the correctness of propagation model of the disease.
Journal Information
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
Tel：(086)0371-86608635
(086)0371-86608633
