This paper introduces the GPS intelligent vehicle navigation system (IVNS). This system can be widely applied to the urban fields, inter province and inter state transport which, as a part of intelligent transport ...This paper introduces the GPS intelligent vehicle navigation system (IVNS). This system can be widely applied to the urban fields, inter province and inter state transport which, as a part of intelligent transport systems(ITS), would contribute toward improving troublesome driving conditions on driver′s benefits. The paper discuss as two key techniques: city geographical information system(GIS), real time correction of the deviation.展开更多
Empirical potential structure refinement is a neutron scattering data analysis algorithm and a software package.It was developed by the disordered materials group in the British spallation neutron source(ISIS)in 1980s...Empirical potential structure refinement is a neutron scattering data analysis algorithm and a software package.It was developed by the disordered materials group in the British spallation neutron source(ISIS)in 1980s,and aims to construct the most-probable atomic structures of disordered materials in the field of chemical physics.It has been extensively used during the past decades,and has generated reliable results.However,it implements a shared-memory architecture with open multi-processing(OpenMP).With the extensive construction of supercomputer clusters and the widespread use of graphics processing unit(GPU)acceleration technology,it is now possible to rebuild the EPSR with these techniques in the effort to improve its calculation speed.In this study,an open source framework NeuDATool is proposed.It is programmed in the object-oriented language C++,can be paralleled across nodes within a computer cluster,and supports GPU acceleration.The performance of NeuDATool has been tested with water and amorphous silica neutron scattering data.The test shows that the software can reconstruct the correct microstructure of the samples,and the calculation speed with GPU acceleration can increase by more than 400 times,compared with CPU serial algorithm at a simulation box that has about 100 thousand atoms.NeuDATool provides another choice to implement simulation in the(neutron)diffraction community,especially for experts who are familiar with C++programming and want to define specific algorithms for their analysis.展开更多
AIM： To introduce and evaluate a new method to re- pair bile duct defect with a degradable stent and au- tologous tissues. METHODS： Eight Ba-Ma mini-pigs were used in this study, Experimental models with common bile...AIM： To introduce and evaluate a new method to re- pair bile duct defect with a degradable stent and au- tologous tissues. METHODS： Eight Ba-Ma mini-pigs were used in this study, Experimental models with common bile duct （CBD） defect （0,5-1,0 cm segment of CBD resected） were established and then CBD was reconstructed by duct to duct anastomosis with a novel degradable stent made of poly [sebacic acid-co-（1,3-propanediol）-co- （1,2-propanediol）]. In addition, a vascularized greater omentum was placed around the stent and both ends of CBD. Cholangiography via gall bladder was per- formed for each pig at postoperative months 1 and 3 to rule out stent translocation and bile duct stricture. Complete blood count was examined pre- and post- operatively to estimate the inflammatory reaction. Liver enzymes and serum bilirubin were examined pre- and post-operatively to evaluate the liver function. Five pigs were sacrificed at month 3 to evaluate the healing of anastomosis. The other three pigs were raised for one year for long-term observation. RESULTS： All the animals underwent surgery success- fully. There was no intraoperative mortality and no bile leakage during the observation period, The white blood cell counts were only slightly increased on day 14 and month 3 postoperatively compared with that before operation, the difference was not statistically significant （P = 0.652）. The plasma level of alanine aminotrans- ferase on day 14 and month 3 postoperatively was also not significantly elevated compared with that before operation （P = 0.810）. Nevertheless, the plasma level of y-glutamyl transferase was increased after opera- tion in both groups （P = 0.004）, especially 2 wk after operation. The level of serum total bilirubin after opera- tion was not significantly elevated compared with that before operation （P = 0.227）, so did the serum direct bilirubin （P = 0.759）. By cholangiography yia gall blad- der, we found that the stent maintained its integrity of shape and was stillin situ at month 1, and it disap- peared completely at month 3. No severe CBD dilation and stricture were observed at both months 1 and 3. No pig died during the 3-too postoperative observation period. No sign of necrosis, bile duct stricture, bile leak- age or abdominal abscess was found at reoperation at month 3 postoperatively. Pigs had neither fragments of stent nor stones formed in the CBD. Collagen deposit was observed in the anastomosis by hematoxylin and eosin （HE） and Masson＇s trichrome stains. No severe cholestasis was observed in liver parenchyma by HE staining. Intestinal obstruction was found in a pig 4 mo after operation, and no bile leakage, bile duct stricture or biliary obstruction were observed in laparotomy. No sign of bile duct stricture or bile leakage was observed in the other two pigs. CONCLUSION： The novel method for repairing bile duct defect yielded a good short-term effect without postoperative bile duct stricture. However, the long- term effect should be further studied.展开更多
The 3400-3600 MHz band is one of the most important candidate frequency bands for the rollout of 5 G system. However, the coexistence between 5 G system and fixed-satellite service(FSS) in this frequency band is one o...The 3400-3600 MHz band is one of the most important candidate frequency bands for the rollout of 5 G system. However, the coexistence between 5 G system and fixed-satellite service(FSS) in this frequency band is one of the most challenging problems for both academic researchers and industry engineers. In this paper, the saturation interference from 5 G base stations to the existing FSS above 3600 MHz is analyzed and the coexistence solution is achieved, which can reduce the interference and guarantee the coexistence between 5 G system and FSS. Furthermore, the Monte Carlo simulation, laboratory test and field test are carried out to verify the coexistence solution.Results show that an isolation distance of 1-2 km is required to avoid the saturation interference in terms of the adjacent bands scenario.To further reduce the isolation distance to 50 m, additional isolation of 35 dB will be necessary, which can be fulfilled by installing a filter at the input port of LNB from a real implementation perspective.展开更多
This study focused on developing a risk assessment method for explosion at a coal reclaim tunnel （CRT） facility. The method was developed based on an analytical hierarchy process （AHP）, which is an expert system t...This study focused on developing a risk assessment method for explosion at a coal reclaim tunnel （CRT） facility. The method was developed based on an analytical hierarchy process （AHP）, which is an expert system that quantifies the factors of explosion incidents, based on events and hierarchies. In this paper, the proposed model was modification from original AHP model, specifically modifying the structure from ＂alternative＇s results＂ to ＂total risk-rating＇s results＂. The total risk-rating is obtained by summing up risk-rating of each factor, where the risk-rating is a multiplication product of the risk value by the AHP weighted value. To support decision-making using the expert system, data on the real conditions of the CRT were collected and analyzed. A physical modeling of the CRT with laboratory-scale experiments was carried out to show the impact of a ventilation system in CRT on diluting the methane gas and coal dust, in order to support the quantification of AHP risk value. The criteria to evaluate the risk of explosion was constructed from six components that are： fuel, oxygen, ignition, confinement, dispersion, and monitoring system. Those components had fifty-two factors that serve as sub-components （root causes）. The main causes of explosion in CRT were found to be： mechanical ventilation failure and abnormal ventilation, breakdown of monitoring system, and coal spontaneous-combustion. Assessments of two CRT facilities at Mine A and Mine B were carried out as a case study in order to check the reliability of the developed AHP method. The results showed that the risk rating of Mine A was classified as high and Mine B was classified as medium, which is in a good agreement with the site conditions.展开更多
The practice of four-character Chinese idioms alteration used in the signboards by substituting character （s） with their homophonous words has grown into a general trend. Fifty-one altered idioms are collected. The ...The practice of four-character Chinese idioms alteration used in the signboards by substituting character （s） with their homophonous words has grown into a general trend. Fifty-one altered idioms are collected. The majority of the modifiers are medium-small store owners. Idiom alteration for specific purpose differs from the idiom misinterpretation. Speedy economic growth and material wealth pursuit social context stimulate the idiom alteration behavior which enforces the pragmatism value orientation. By modifying idioms into four-character structures of strong practical effect, the obvious pragamtic value of the businessmen and of Chinese are manifested. A causal analysis method is used.展开更多
To position personnel in mines, the study discussed in this paper built on the tunnel personnel positioning method on the basis of both TOA and location-finger print(LFP) positioning. Given non-line of sight(NLOS) tim...To position personnel in mines, the study discussed in this paper built on the tunnel personnel positioning method on the basis of both TOA and location-finger print(LFP) positioning. Given non-line of sight(NLOS) time delay in signal transmission caused by facilities and equipment shielding in tunnels and TOA measurement errors in both LFP database data and real-time data, this paper puts forth a database data de-noising algorithm based on distance threshold limitation and modified mean filtering(MMF), as well as a real-time data suppression algorithm based on speed threshold limitation and MMF.On this basis, a nearest neighboring data matching algorithm based on historical location and the speed threshold limitation is used to estimate personnel location and realize accurate personnel positioning.The results from both simulation and the experiment suggest that: compared with the basic LFP positioning method and the method that only suppresses real-time data error, the tunnel personnel positioning methods based on TOA and modified LFP positioning permits effectively eliminating error in TOA measurement, making the measured data close to the true positional data, and dropping the positioning error:the maximal positioning error in measurements from experiment drops by 9 and 3 m, respectively, and the positioning accuracy of 3 m is achievable in the condition used in the experiment.展开更多
By means of experiments of C02 miscibility with crude oil, four nonpolar chemicals were evaluated in order to enhance the miscibility of C02 with crude oil. Through pre-slug injection and joint injection of toluene in...By means of experiments of C02 miscibility with crude oil, four nonpolar chemicals were evaluated in order to enhance the miscibility of C02 with crude oil. Through pre-slug injection and joint injection of toluene in CO2, crude oil displacement experiments in the slim-tube were conducted to investigate effects of the toluene- enhanced C02 flooding under simulated subterranean reservoir conditions. Experimental results showed that toluene can enhance extraction of oil into C02 and dissolution of C02 into oil with the increment of 251% and 64% respectively. Addition of toluene can obviously improve the oil recovery in either pre-slug injection or joint injection, and the crude oil recovery increased with the increase of the toluene concentration. The oil recov- ery can increase by 22.5% in pre-slug injection with the high toluene concentration. Pre-slug injection was recom- mended because it can consume less toluene than joint injection. This work could be useful to development and application of the CO） flooding in the oil recoverv as well as CO2 emission reduction.展开更多
Virtual reality technology is a brand new comprehensive information technology emerging during the end of 21 st century. In recent years in particular, it gains rapid development, involving industries like education, ...Virtual reality technology is a brand new comprehensive information technology emerging during the end of 21 st century. In recent years in particular, it gains rapid development, involving industries like education, industry, military, entertainment and medicine. Combined with the characteristics of railway maintenance training, this thesis proposes the application of virtual reality in courseware, distance education, locomotive simulation driving, locomotive overhauling oil and breakdown processing, and illustrates key technology and solution of the exploitation of virtual reality technology.展开更多
文摘This paper introduces the GPS intelligent vehicle navigation system (IVNS). This system can be widely applied to the urban fields, inter province and inter state transport which, as a part of intelligent transport systems(ITS), would contribute toward improving troublesome driving conditions on driver′s benefits. The paper discuss as two key techniques: city geographical information system(GIS), real time correction of the deviation.
基金supported by the National Key Research and Development Program of China(No.2017YFA-0403703)the National Natural Science Foundation of China(No.U1830205,No.21674020).
文摘Empirical potential structure refinement is a neutron scattering data analysis algorithm and a software package.It was developed by the disordered materials group in the British spallation neutron source(ISIS)in 1980s,and aims to construct the most-probable atomic structures of disordered materials in the field of chemical physics.It has been extensively used during the past decades,and has generated reliable results.However,it implements a shared-memory architecture with open multi-processing(OpenMP).With the extensive construction of supercomputer clusters and the widespread use of graphics processing unit(GPU)acceleration technology,it is now possible to rebuild the EPSR with these techniques in the effort to improve its calculation speed.In this study,an open source framework NeuDATool is proposed.It is programmed in the object-oriented language C++,can be paralleled across nodes within a computer cluster,and supports GPU acceleration.The performance of NeuDATool has been tested with water and amorphous silica neutron scattering data.The test shows that the software can reconstruct the correct microstructure of the samples,and the calculation speed with GPU acceleration can increase by more than 400 times,compared with CPU serial algorithm at a simulation box that has about 100 thousand atoms.NeuDATool provides another choice to implement simulation in the(neutron)diffraction community,especially for experts who are familiar with C++programming and want to define specific algorithms for their analysis.
基金Supported by Grants from Science and Technology Department of Zhejiang Province, No. 2009C33027 and No. 2009R50040
文摘AIM： To introduce and evaluate a new method to re- pair bile duct defect with a degradable stent and au- tologous tissues. METHODS： Eight Ba-Ma mini-pigs were used in this study, Experimental models with common bile duct （CBD） defect （0,5-1,0 cm segment of CBD resected） were established and then CBD was reconstructed by duct to duct anastomosis with a novel degradable stent made of poly [sebacic acid-co-（1,3-propanediol）-co- （1,2-propanediol）]. In addition, a vascularized greater omentum was placed around the stent and both ends of CBD. Cholangiography via gall bladder was per- formed for each pig at postoperative months 1 and 3 to rule out stent translocation and bile duct stricture. Complete blood count was examined pre- and post- operatively to estimate the inflammatory reaction. Liver enzymes and serum bilirubin were examined pre- and post-operatively to evaluate the liver function. Five pigs were sacrificed at month 3 to evaluate the healing of anastomosis. The other three pigs were raised for one year for long-term observation. RESULTS： All the animals underwent surgery success- fully. There was no intraoperative mortality and no bile leakage during the observation period, The white blood cell counts were only slightly increased on day 14 and month 3 postoperatively compared with that before operation, the difference was not statistically significant （P = 0.652）. The plasma level of alanine aminotrans- ferase on day 14 and month 3 postoperatively was also not significantly elevated compared with that before operation （P = 0.810）. Nevertheless, the plasma level of y-glutamyl transferase was increased after opera- tion in both groups （P = 0.004）, especially 2 wk after operation. The level of serum total bilirubin after opera- tion was not significantly elevated compared with that before operation （P = 0.227）, so did the serum direct bilirubin （P = 0.759）. By cholangiography yia gall blad- der, we found that the stent maintained its integrity of shape and was stillin situ at month 1, and it disap- peared completely at month 3. No severe CBD dilation and stricture were observed at both months 1 and 3. No pig died during the 3-too postoperative observation period. No sign of necrosis, bile duct stricture, bile leak- age or abdominal abscess was found at reoperation at month 3 postoperatively. Pigs had neither fragments of stent nor stones formed in the CBD. Collagen deposit was observed in the anastomosis by hematoxylin and eosin （HE） and Masson＇s trichrome stains. No severe cholestasis was observed in liver parenchyma by HE staining. Intestinal obstruction was found in a pig 4 mo after operation, and no bile leakage, bile duct stricture or biliary obstruction were observed in laparotomy. No sign of bile duct stricture or bile leakage was observed in the other two pigs. CONCLUSION： The novel method for repairing bile duct defect yielded a good short-term effect without postoperative bile duct stricture. However, the long- term effect should be further studied.
基金partly supported by National Natural Science Foundation of China (NSFC) (Grant No. 61525101, 61631003)
文摘The 3400-3600 MHz band is one of the most important candidate frequency bands for the rollout of 5 G system. However, the coexistence between 5 G system and fixed-satellite service(FSS) in this frequency band is one of the most challenging problems for both academic researchers and industry engineers. In this paper, the saturation interference from 5 G base stations to the existing FSS above 3600 MHz is analyzed and the coexistence solution is achieved, which can reduce the interference and guarantee the coexistence between 5 G system and FSS. Furthermore, the Monte Carlo simulation, laboratory test and field test are carried out to verify the coexistence solution.Results show that an isolation distance of 1-2 km is required to avoid the saturation interference in terms of the adjacent bands scenario.To further reduce the isolation distance to 50 m, additional isolation of 35 dB will be necessary, which can be fulfilled by installing a filter at the input port of LNB from a real implementation perspective.
文摘This study focused on developing a risk assessment method for explosion at a coal reclaim tunnel （CRT） facility. The method was developed based on an analytical hierarchy process （AHP）, which is an expert system that quantifies the factors of explosion incidents, based on events and hierarchies. In this paper, the proposed model was modification from original AHP model, specifically modifying the structure from ＂alternative＇s results＂ to ＂total risk-rating＇s results＂. The total risk-rating is obtained by summing up risk-rating of each factor, where the risk-rating is a multiplication product of the risk value by the AHP weighted value. To support decision-making using the expert system, data on the real conditions of the CRT were collected and analyzed. A physical modeling of the CRT with laboratory-scale experiments was carried out to show the impact of a ventilation system in CRT on diluting the methane gas and coal dust, in order to support the quantification of AHP risk value. The criteria to evaluate the risk of explosion was constructed from six components that are： fuel, oxygen, ignition, confinement, dispersion, and monitoring system. Those components had fifty-two factors that serve as sub-components （root causes）. The main causes of explosion in CRT were found to be： mechanical ventilation failure and abnormal ventilation, breakdown of monitoring system, and coal spontaneous-combustion. Assessments of two CRT facilities at Mine A and Mine B were carried out as a case study in order to check the reliability of the developed AHP method. The results showed that the risk rating of Mine A was classified as high and Mine B was classified as medium, which is in a good agreement with the site conditions.
文摘The practice of four-character Chinese idioms alteration used in the signboards by substituting character （s） with their homophonous words has grown into a general trend. Fifty-one altered idioms are collected. The majority of the modifiers are medium-small store owners. Idiom alteration for specific purpose differs from the idiom misinterpretation. Speedy economic growth and material wealth pursuit social context stimulate the idiom alteration behavior which enforces the pragmatism value orientation. By modifying idioms into four-character structures of strong practical effect, the obvious pragamtic value of the businessmen and of Chinese are manifested. A causal analysis method is used.
基金Project supports from the National Science Foundation of China(No.51134024)the National High Technology Research and development Program of China(No.2012AA062203)are acknowledged
文摘To position personnel in mines, the study discussed in this paper built on the tunnel personnel positioning method on the basis of both TOA and location-finger print(LFP) positioning. Given non-line of sight(NLOS) time delay in signal transmission caused by facilities and equipment shielding in tunnels and TOA measurement errors in both LFP database data and real-time data, this paper puts forth a database data de-noising algorithm based on distance threshold limitation and modified mean filtering(MMF), as well as a real-time data suppression algorithm based on speed threshold limitation and MMF.On this basis, a nearest neighboring data matching algorithm based on historical location and the speed threshold limitation is used to estimate personnel location and realize accurate personnel positioning.The results from both simulation and the experiment suggest that: compared with the basic LFP positioning method and the method that only suppresses real-time data error, the tunnel personnel positioning methods based on TOA and modified LFP positioning permits effectively eliminating error in TOA measurement, making the measured data close to the true positional data, and dropping the positioning error:the maximal positioning error in measurements from experiment drops by 9 and 3 m, respectively, and the positioning accuracy of 3 m is achievable in the condition used in the experiment.
基金Supported by the National Science&Technology Pillar Program(2012BAC24B03)
文摘By means of experiments of C02 miscibility with crude oil, four nonpolar chemicals were evaluated in order to enhance the miscibility of C02 with crude oil. Through pre-slug injection and joint injection of toluene in CO2, crude oil displacement experiments in the slim-tube were conducted to investigate effects of the toluene- enhanced C02 flooding under simulated subterranean reservoir conditions. Experimental results showed that toluene can enhance extraction of oil into C02 and dissolution of C02 into oil with the increment of 251% and 64% respectively. Addition of toluene can obviously improve the oil recovery in either pre-slug injection or joint injection, and the crude oil recovery increased with the increase of the toluene concentration. The oil recov- ery can increase by 22.5% in pre-slug injection with the high toluene concentration. Pre-slug injection was recom- mended because it can consume less toluene than joint injection. This work could be useful to development and application of the CO） flooding in the oil recoverv as well as CO2 emission reduction.
文摘Virtual reality technology is a brand new comprehensive information technology emerging during the end of 21 st century. In recent years in particular, it gains rapid development, involving industries like education, industry, military, entertainment and medicine. Combined with the characteristics of railway maintenance training, this thesis proposes the application of virtual reality in courseware, distance education, locomotive simulation driving, locomotive overhauling oil and breakdown processing, and illustrates key technology and solution of the exploitation of virtual reality technology.
