In order to improve the accuracy and reliability of the driving fatigue detection based on a single feature, a new detection algorithm based on multiple features is proposed. Two direct driver＇s facial features refle...In order to improve the accuracy and reliability of the driving fatigue detection based on a single feature, a new detection algorithm based on multiple features is proposed. Two direct driver＇s facial features reflecting fatigue and one indirect vehicle behavior feature indicating fatigue are considered. Meanwhile, T-S fuzzy neural network（TSFNN）is adopted to recognize the driving fatigue of drivers. For the structure identification of the TSFNN, subtractive clustering（SC） is used to confirm the fuzzy rules and their correlative parameters. Moreover, the particle swarm optimization （PSO）algorithm is improved to train the TSFNN. Simulation results and experiments on vehicles show that the proposed algorithm can effectively improve the convergence speed and the recognition accuracy of the TSFNN, as well as enhance the correct rate of driving fatigue detection.展开更多
The present study is an investigation of the properties of poly(vinyl alcohol),which would be a better contact lens mate- rial than conventional HEMA in some ways.A transparent PVA hydrogel was prepared from a PVA sol...The present study is an investigation of the properties of poly(vinyl alcohol),which would be a better contact lens mate- rial than conventional HEMA in some ways.A transparent PVA hydrogel was prepared from a PVA solution in a mixed solvent consisting of water and a water-miscible organic solvent,DMSO,by the freezing-thawing method.The water content,visible light transmittance,mechanical and swelling properties of the hydrogels were evaluated as a function of PVA concentration and number of freeze-thaw cycles.The results show that the properties of PVA hydrogels depend on the polymer concentration,the number of freeze-thaw cycles and the addition of the organic solvent.展开更多
The MgNi26 alloy was prepared by three different methods of gravity casting (GC), mechanical alloying (MA) and rapid solidification (RS). All samples were electrochemically hydrided in a 6 mol/L KOH solution at 80 ...The MgNi26 alloy was prepared by three different methods of gravity casting (GC), mechanical alloying (MA) and rapid solidification (RS). All samples were electrochemically hydrided in a 6 mol/L KOH solution at 80 °C for 240 min. The structures and phase compositions of the alloys were studied using optical microscopy and scanning electron microscopy, energy dispersive spectrometry and X-ray diffraction. A temperature-programmed desorption technique was used to measure the absorbed hydrogen and study the dehydriding process. The content of hydrogen absorbed by the MgNi26-MA (approximately 1.3%, mass fraction) was 30 times higher than that of the MgNi26-GC. The MgNi26-RS sample absorbed only 0.1% of hydrogen. The lowest temperature for hydrogen evolution was exhibited by the MgNi26-MA. Compared with pure commercial MgH2, the decomposition temperature was reduced by more than 200 °C. The favourable phase and structural composition of the MgNi26-MA sample were the reasons for the best hydriding and dehydriding properties.展开更多
This paper has analyzed merits and demerits of both neural network technique and of the information fusion methods based on the D-S (dempster-shafer evidence) Theory as well as their complementarity, proposed the hier...This paper has analyzed merits and demerits of both neural network technique and of the information fusion methods based on the D-S (dempster-shafer evidence) Theory as well as their complementarity, proposed the hierarchical information fusion fault diagnosis strategy by combining the neural network technique and the fused decision diagnosis based on D-S Theory, and established a corresponding functional model. Thus, we can not only solve a series of problems caused by rapid growth in size and complexity of neural network structure with diagnosis parameters increasing, but also can provide effective method for basic probability assignment in D-S Theory. The application of the strategy to diagnosing faults of motor bearings has proved that this method is of fairly high accuracy and reliability in fault diagnosis.展开更多
目的研制一台冷沉淀制备辅助装置,缩短冷沉淀制备的时间,保证冷沉淀中有效成分的活性。方法采用ALIENTEK Mini STM32单片机作为控制模块,采用步进电机作为执行模块,通过Keil编写开发板程序,五位按键控制四挡制备速度及正反转。结果将机...目的研制一台冷沉淀制备辅助装置,缩短冷沉淀制备的时间,保证冷沉淀中有效成分的活性。方法采用ALIENTEK Mini STM32单片机作为控制模块,采用步进电机作为执行模块,通过Keil编写开发板程序,五位按键控制四挡制备速度及正反转。结果将机械力作用于血袋管路,加速融化血浆排出,大大缩短冷沉淀制备时间。结论该装置改变只依靠虹吸原理制备的现状,解决了冷沉淀制备时间长的问题,保证制品的质量,操作简单,推广前景广阔。展开更多
Objective： To search for the best procedure on preparation ofacellular bovine pericardium,so to provide scaffolds for constructing tissue-engineering Methods： The bovine pericardiums were treated with 5 methods, whi...Objective： To search for the best procedure on preparation ofacellular bovine pericardium,so to provide scaffolds for constructing tissue-engineering Methods： The bovine pericardiums were treated with 5 methods, which were divided into 6 groupsGroup A： Fresh bovinepericardium; Group B： Trypsin-detergent group;Group C： Freeze-thaw-detergent 24 h group; Group I）： Freeze-thaw-detergent 48 h group; Group Fz Freeze-thaw-nuclease group; Group F： Detergent-nuclease group. Then, by HE staining and scanning electron microscope to observe the effects ofdecellularization and fibrous changes among the 6 groups; by water content testingonechanical testing to observe the changes in physical properties of the matrix; by detecting the DNA content of each group to determine the effect of deeellularization qualitatively; by eytotoxieity test to detect the biocompatibility of bovine pericardium in each group. Results： The 5 methods can all remove the cellular components effectively, compared with the fresh bovine pericardium,the water content of each deeellularized group were increased （P〈0.05）, while the DNA content decreased （P〈0.05）, with statistically significant differences. Of group E, the fibers were a little disorder, with the largest tension and the elastic modulus increased, while the rupture tensile rate decreased. Compared with fresh bovine pericardium,the largest tension of the other decellularization groups were all decreased （P〈0.05）. The fibers of group B, group D were irregularly arranged and also with ruptures, both the elastic modulus and the rupture tensile rate decreased（P〈0.05）. In group C and F, the fibers were dense and their direction was normal, the elastic modulus and the rupture tensile rate were similar to the fresh bovine pericardium （P〉0.05）. Cytotoxicity results showed that the cell toxicity of group B, group C, group D, group E and group F were respectively 0.9, 0.6, 1.0, 1.0 and 0.5, each group were qualified toxicity test, in which group C and group F were with the lowest eytotoxieity. Conclusion： Group C and group F can remove the cell components of bovine pericardium successfully,while maintaining the major structural components and the histological and biological properties of bovine pericardium,and with low cytotoxicity.However, group C is more economical than group F,and easier to operate. So the method on freeze-thaw-detergent 24 h can be the best choice to produce a decellularized bovine pericardium.展开更多
The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great difference...The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great differences,static melt crystallization was applied to separate and purify durene from its isomers.Crystallization experiments were carried out under various operating conditions.The effects of cooling rate,crystallization temperature,sweating temperature and sweating time on the yield and purity of crystal were investigated.Orthogonal experimental design method was adopted to analyze the factors that may affect the yield of durene.Under the optimal crystallization conditions,the purity of durene could reach as high as 99.06%with the yield of 75.3%through one crystallization process.By fitting purification data based on sweating time in isothermal operations,the purification rate coefficient was obtained.展开更多
The study of snow and ice melt （SIM） is important in water-scarce arid regions for the assessment of water supply and quality. These studies involve unique difficulties, especially in the calibration of hydro-models...The study of snow and ice melt （SIM） is important in water-scarce arid regions for the assessment of water supply and quality. These studies involve unique difficulties, especially in the calibration of hydro-models because there is no direct way to continuously measure the SIM at hydrostations. The recursive digital filter （RDF） and the isotopic hydro-geochemical method （IHM） were coupled to separate the SIM from eight observed series of alpine streamflows in northwestern China. Validation of the calibrated methods suggested a good capture of the SIM characteristics with fair accuracy in both space and time. Applications of the coupled methods in the upper reaches of the Hei River Basin （HRB） suggested a double peak curve of the SIM fraction to streamflow for the multi-component recharged （MCR） rivers, while a single peak curve was suggested for the rainfall-dominant recharged （RDR） rivers. Given inter-annual statistics of the separation, both types of the alpine rivers have experienced an obvious decrease of SIM since 196os. In the past 10 years, the SIM in the two types of rivers has risen to the levels of the 1970s, but has remained lower than the level of the 1960s. The study provided a considerable evidence to quantify the alpine SIMbased on the separation of observed data series at gauge stations. Application of the coupled method could be helpful in the calibration and validation of SIM-related hydro-models in alpine regions.展开更多
OBJECTIVE: To develop a more precise and accurate method, and identified a procedure to measure whether an acupoint had been correctly located.METHODS: On the face, we used an acupoint location from different acupunct...OBJECTIVE: To develop a more precise and accurate method, and identified a procedure to measure whether an acupoint had been correctly located.METHODS: On the face, we used an acupoint location from different acupuncture experts and obtained the most precise and accurate values of acupoint location based on the consistency information fusion algorithm, through a virtual simulation of the facial orientation coordinate system.RESULTS: Because of inconsistencies in each acupuncture expert's original data, the system error could not be modified using the characteristics ofthe general weight calculation. First, we corrected each expert of acupoint location system error itself,to obtain a rational quantification for each expert of acupuncture and moxibustion acupoint location consistent support degree, to obtain pointwise variable precision fusion results, to put every expert's acupuncture acupoint location fusion error enhanced to pointwise variable precision. Then, we more effectively used the measured characteristics of different acupuncture expert's acupoint location, to improve the measurement information utilization efficiency and acupuncture acupoint location precision and accuracy.CONCLUSION: Based on using the consistency matrix pointwise fusion method on the acupuncture experts' acupoint location values, each expert's acupoint location information could be calculated, and the most precise and accurate values of each expert's acupoint location could be obtained.展开更多
基金The National Key Technologies R & D Program during the 11th Five-Year Plan Period(No.2009BAG13A04)the Ph.D.Programs Foundation of Ministry of Education of China(No.200802861061)the Transportation Science Research Project of Jiangsu Province(No.08X09)
文摘In order to improve the accuracy and reliability of the driving fatigue detection based on a single feature, a new detection algorithm based on multiple features is proposed. Two direct driver＇s facial features reflecting fatigue and one indirect vehicle behavior feature indicating fatigue are considered. Meanwhile, T-S fuzzy neural network（TSFNN）is adopted to recognize the driving fatigue of drivers. For the structure identification of the TSFNN, subtractive clustering（SC） is used to confirm the fuzzy rules and their correlative parameters. Moreover, the particle swarm optimization （PSO）algorithm is improved to train the TSFNN. Simulation results and experiments on vehicles show that the proposed algorithm can effectively improve the convergence speed and the recognition accuracy of the TSFNN, as well as enhance the correct rate of driving fatigue detection.
基金Projects 50575106 supported by the National Natural Science Foundation of ChinaBG2007046 by the High Technology Project of Jiangsu Province
文摘The present study is an investigation of the properties of poly(vinyl alcohol),which would be a better contact lens mate- rial than conventional HEMA in some ways.A transparent PVA hydrogel was prepared from a PVA solution in a mixed solvent consisting of water and a water-miscible organic solvent,DMSO,by the freezing-thawing method.The water content,visible light transmittance,mechanical and swelling properties of the hydrogels were evaluated as a function of PVA concentration and number of freeze-thaw cycles.The results show that the properties of PVA hydrogels depend on the polymer concentration,the number of freeze-thaw cycles and the addition of the organic solvent.
基金the Czech Science Foundation (project No. P108/12/G043) for the financial support of this research
文摘The MgNi26 alloy was prepared by three different methods of gravity casting (GC), mechanical alloying (MA) and rapid solidification (RS). All samples were electrochemically hydrided in a 6 mol/L KOH solution at 80 °C for 240 min. The structures and phase compositions of the alloys were studied using optical microscopy and scanning electron microscopy, energy dispersive spectrometry and X-ray diffraction. A temperature-programmed desorption technique was used to measure the absorbed hydrogen and study the dehydriding process. The content of hydrogen absorbed by the MgNi26-MA (approximately 1.3%, mass fraction) was 30 times higher than that of the MgNi26-GC. The MgNi26-RS sample absorbed only 0.1% of hydrogen. The lowest temperature for hydrogen evolution was exhibited by the MgNi26-MA. Compared with pure commercial MgH2, the decomposition temperature was reduced by more than 200 °C. The favourable phase and structural composition of the MgNi26-MA sample were the reasons for the best hydriding and dehydriding properties.
文摘This paper has analyzed merits and demerits of both neural network technique and of the information fusion methods based on the D-S (dempster-shafer evidence) Theory as well as their complementarity, proposed the hierarchical information fusion fault diagnosis strategy by combining the neural network technique and the fused decision diagnosis based on D-S Theory, and established a corresponding functional model. Thus, we can not only solve a series of problems caused by rapid growth in size and complexity of neural network structure with diagnosis parameters increasing, but also can provide effective method for basic probability assignment in D-S Theory. The application of the strategy to diagnosing faults of motor bearings has proved that this method is of fairly high accuracy and reliability in fault diagnosis.
文摘目的研制一台冷沉淀制备辅助装置,缩短冷沉淀制备的时间,保证冷沉淀中有效成分的活性。方法采用ALIENTEK Mini STM32单片机作为控制模块,采用步进电机作为执行模块,通过Keil编写开发板程序,五位按键控制四挡制备速度及正反转。结果将机械力作用于血袋管路,加速融化血浆排出,大大缩短冷沉淀制备时间。结论该装置改变只依靠虹吸原理制备的现状,解决了冷沉淀制备时间长的问题,保证制品的质量,操作简单,推广前景广阔。
文摘Objective： To search for the best procedure on preparation ofacellular bovine pericardium,so to provide scaffolds for constructing tissue-engineering Methods： The bovine pericardiums were treated with 5 methods, which were divided into 6 groupsGroup A： Fresh bovinepericardium; Group B： Trypsin-detergent group;Group C： Freeze-thaw-detergent 24 h group; Group I）： Freeze-thaw-detergent 48 h group; Group Fz Freeze-thaw-nuclease group; Group F： Detergent-nuclease group. Then, by HE staining and scanning electron microscope to observe the effects ofdecellularization and fibrous changes among the 6 groups; by water content testingonechanical testing to observe the changes in physical properties of the matrix; by detecting the DNA content of each group to determine the effect of deeellularization qualitatively; by eytotoxieity test to detect the biocompatibility of bovine pericardium in each group. Results： The 5 methods can all remove the cellular components effectively, compared with the fresh bovine pericardium,the water content of each deeellularized group were increased （P〈0.05）, while the DNA content decreased （P〈0.05）, with statistically significant differences. Of group E, the fibers were a little disorder, with the largest tension and the elastic modulus increased, while the rupture tensile rate decreased. Compared with fresh bovine pericardium,the largest tension of the other decellularization groups were all decreased （P〈0.05）. The fibers of group B, group D were irregularly arranged and also with ruptures, both the elastic modulus and the rupture tensile rate decreased（P〈0.05）. In group C and F, the fibers were dense and their direction was normal, the elastic modulus and the rupture tensile rate were similar to the fresh bovine pericardium （P〉0.05）. Cytotoxicity results showed that the cell toxicity of group B, group C, group D, group E and group F were respectively 0.9, 0.6, 1.0, 1.0 and 0.5, each group were qualified toxicity test, in which group C and group F were with the lowest eytotoxieity. Conclusion： Group C and group F can remove the cell components of bovine pericardium successfully,while maintaining the major structural components and the histological and biological properties of bovine pericardium,and with low cytotoxicity.However, group C is more economical than group F,and easier to operate. So the method on freeze-thaw-detergent 24 h can be the best choice to produce a decellularized bovine pericardium.
基金Supported by the National Natural Science Foundation of China(21176172)Top Talents Program of Yunnan Province,China(2011HA010)
文摘The purification and separation of durene from the mixture containing durene isomers were studied.Since the boiling points of tetramethyl benzene isomers are very close but their melting points are of great differences,static melt crystallization was applied to separate and purify durene from its isomers.Crystallization experiments were carried out under various operating conditions.The effects of cooling rate,crystallization temperature,sweating temperature and sweating time on the yield and purity of crystal were investigated.Orthogonal experimental design method was adopted to analyze the factors that may affect the yield of durene.Under the optimal crystallization conditions,the purity of durene could reach as high as 99.06%with the yield of 75.3%through one crystallization process.By fitting purification data based on sweating time in isothermal operations,the purification rate coefficient was obtained.
基金supported by the following grants:National Key Research and Development Program of China (Grant No. 2009CB421306)the NSFC Project (Grant Nos. 41001014, 51209119) NSFC Projects (Grant Nos. 41240002, 91225301)+1 种基金the NSFC Key Project (Grant No. 91125010)the MAIRS Project funded by the NASA LCLUC Program (Grant No. NNX08AH50G)
文摘The study of snow and ice melt （SIM） is important in water-scarce arid regions for the assessment of water supply and quality. These studies involve unique difficulties, especially in the calibration of hydro-models because there is no direct way to continuously measure the SIM at hydrostations. The recursive digital filter （RDF） and the isotopic hydro-geochemical method （IHM） were coupled to separate the SIM from eight observed series of alpine streamflows in northwestern China. Validation of the calibrated methods suggested a good capture of the SIM characteristics with fair accuracy in both space and time. Applications of the coupled methods in the upper reaches of the Hei River Basin （HRB） suggested a double peak curve of the SIM fraction to streamflow for the multi-component recharged （MCR） rivers, while a single peak curve was suggested for the rainfall-dominant recharged （RDR） rivers. Given inter-annual statistics of the separation, both types of the alpine rivers have experienced an obvious decrease of SIM since 196os. In the past 10 years, the SIM in the two types of rivers has risen to the levels of the 1970s, but has remained lower than the level of the 1960s. The study provided a considerable evidence to quantify the alpine SIMbased on the separation of observed data series at gauge stations. Application of the coupled method could be helpful in the calibration and validation of SIM-related hydro-models in alpine regions.
基金Supported by the Key Program of State Administration of Traditional Chinese Medicine of China:the Science of Acupuncture and Moxibustion(No.ZYSNXD-CC-ZDXK-07)
文摘OBJECTIVE: To develop a more precise and accurate method, and identified a procedure to measure whether an acupoint had been correctly located.METHODS: On the face, we used an acupoint location from different acupuncture experts and obtained the most precise and accurate values of acupoint location based on the consistency information fusion algorithm, through a virtual simulation of the facial orientation coordinate system.RESULTS: Because of inconsistencies in each acupuncture expert's original data, the system error could not be modified using the characteristics ofthe general weight calculation. First, we corrected each expert of acupoint location system error itself,to obtain a rational quantification for each expert of acupuncture and moxibustion acupoint location consistent support degree, to obtain pointwise variable precision fusion results, to put every expert's acupuncture acupoint location fusion error enhanced to pointwise variable precision. Then, we more effectively used the measured characteristics of different acupuncture expert's acupoint location, to improve the measurement information utilization efficiency and acupuncture acupoint location precision and accuracy.CONCLUSION: Based on using the consistency matrix pointwise fusion method on the acupuncture experts' acupoint location values, each expert's acupoint location information could be calculated, and the most precise and accurate values of each expert's acupoint location could be obtained.
