A P-vector method was optimized using variational data assimilation technique, with which the vertical structures and seasonal variations of zonal velocities and transports were investigated. The results showed that w...A P-vector method was optimized using variational data assimilation technique, with which the vertical structures and seasonal variations of zonal velocities and transports were investigated. The results showed that westward and eastward flowes occur in the Luzon Strait in the same period in a year. However the net volume transport is westward. In the upper level (0m -500m),the westward flow exits in the middle and south of the Luzon Strait, and the eastward flow exits in the north. There are two centers of westward flow and one center of eastward flow. In the middle of the Luzon Strait, westward and eastward flowes appear alternately in vertical direction. The westward flow strengthens in winter and weakens in summer. The net volume transport is strong in winter (5.53 Sv) but weak in summer (0.29 Sv). Except in summer, the volume transport in the upper level accounts for more than half of the total volume transport (0m bottom). In summer, the net volume transport in the upper level is eastward (1.01 Sv), but westward underneath.展开更多
BACKGROUND The Ilizarov bone transport(IBT)and the Masquelet induced membrane technique(IMT)have specific merits and shortcomings,but numerous studies have shown their efficacy in the management of extensive long-bone...BACKGROUND The Ilizarov bone transport(IBT)and the Masquelet induced membrane technique(IMT)have specific merits and shortcomings,but numerous studies have shown their efficacy in the management of extensive long-bone defects of various etiologies,including congenital deficiencies.Combining their strong benefits seems a promising strategy to enhance bone regeneration and reduce the risk of refractures in the management of post-traumatic and congenital defects and nonunion that failed to respond to other treatments.AIM To combine IBT and IMT for the management of severe tibial defects and pseudarthrosis,and present preliminary results of this technological solution.METHODS Seven adults with post-traumatic tibial defects(subgroup A)and nine children(subgroup B)with congenital pseudarthrosis of the tibia(CPT)were treated with the combination of IMT and IBT after the failure of previous treatments.The mean number of previous surgeries was 2.0±0.2 in subgroup A and 3.3±0.7 in subgroup B.Step 1 included Ilizarov frame placement and spacer introduction into the defect to generate the induced membrane which remained in the interfragmental gap after spacer removal.Step 2 was an osteotomy and bone transport of the fragment through the tunnel in the induced membrane,its compression and docking for consolidation without grafting.The outcomes were retrospectively studied after a mean follow-up of 20.8±2.7 mo in subgroup A and 25.3±2.3 mo in subgroup B.RESULTS The“true defect”after resection was 13.3±1.7%in subgroup A and 31.0±3.0%in subgroup B relative to the contralateral limb.Upon completion of treatment,defects were filled by 75.4±10.6%and 34.6±4.2%,respectively.Total duration of external fixation was 397±9.2 and 270.1±16.3 d,including spacer retention time of 42.4±4.5 and 55.8±6.6 d,in subgroups A and B,respectively.Bone infection was not observed.Postoperative complications were several cases of pin-tract infection and regenerate deformity in both subgroups.Ischemic regeneration was observed in two cases of subgroup B.Complications were corrected during the course of treatment.Bone union was achieved in all patients of subgroup A and in seven patients of subgroup B.One non-united CPT case was further treated with the Ilizarov compression method only and achieved union.After a follow-up period of two to three years,refractures occurred in four cases of united CPT.CONCLUSION The combination of IMT and IBT provides good outcomes in post-traumatic tibial defects after previous treatment failure but external fixation is longer due to spacer retention.Refractures may occur in severe CPT.展开更多
The transport cross-section based on inflow transport approximation can significantly improve the accuracy of light water reactor(LWR)analysis,especially for the treatment of the anisotropic scattering effect.The prev...The transport cross-section based on inflow transport approximation can significantly improve the accuracy of light water reactor(LWR)analysis,especially for the treatment of the anisotropic scattering effect.The previous inflow transport approximation is based on the moderator cross-section and normalized fission source,which is approximated using transport theory.Although the accuracy of reactivity is increased,the P0 flux moment has a large error in the Monte Carlo code.In this study,an improved inflow transport approximation was introduced with homogenization techniques,applying the homogenized cross-section and accurate fission source.The numerical results indicated that the improved inflow transport approximation can increase the P0 flux moment accuracy and maintain the reactivity calculation precision with the previous inflow transport approximation in typical LWR cases.In addition to this investigation,the improved inflow transport approximation is related to the temperature factors.The improved inflow transport approximation is flexible and accurate in the treatment of the anisotropic scattering effect,which can be directly used in the temperature-dependent nuclear data library.展开更多
Large-sized (~2 inch, 50.8 mm) γ-LiAlO2 single crystal has been grown by conventional Czochralski (Cz) method, but the crystal has a milky, dendriform center. The samples taken from transparent and milky parts w...Large-sized (~2 inch, 50.8 mm) γ-LiAlO2 single crystal has been grown by conventional Czochralski (Cz) method, but the crystal has a milky, dendriform center. The samples taken from transparent and milky parts were ground and examined by X-ray diffraction. All diffraction peaks could be indexed in γ-LiAlO2. The crystal quality was characterized by X-ray rocking curve. The full-width at half-maximum (FWHM) values are 116.9 and 132.0 arcsec for transparent and milky parts, respectively. The vapor transport equilibrium (VTE) technique was introduced to modify the crystal quality. After 1000℃/48 h, 1100℃/48 h, 1200℃/48 h VTE processes, the FWHM values dropped to 44.2 and 55.2 arcsec for transparent and milky part, respectively. The optical transmission of transparent part was greatly enhanced from 85% to 90%, and transmission of milky part from 75% to 80% in the range of 190~1900 nm at room temperature. When the VTE temperature was raised to 1300℃, the sample cracked and FWHM values of transparent and milky parts were increased to 55.2 and 80.9 arcsec, respectively. By combining Cz technique with VTE technique, large-sized and high quality γ-LiAlO2 crystal can be obtained.展开更多
Most drug products on the global pharmaceutical market are administered orally.The absorption of oral drug in the intestine is an important factor to determine the drug bioavailability.There are many intestinal transp...Most drug products on the global pharmaceutical market are administered orally.The absorption of oral drug in the intestine is an important factor to determine the drug bioavailability.There are many intestinal transporters expressed on the small intestine and the transporters can be classified into two major families,SLC family and ABC family.They mediate drug absorption,distribution,excretion and drugedrug interaction.Understanding the transport mechanism can improve the effectivity and safety of drug and guide clinical rational use of drugs.The roles of drug transporters can be assessed in vitro and in vivo,using techniques spanning from cellular expression systems to gene knockout animals.The purposes of this article were to introduce the main transporters in the intestinal tract,to explain the transport mechanism and to compare the limitations and applications of techniques used to evaluate interactions of drugs and transporters.展开更多
EDI is an abbreviation for Electronic Data Interchange. It can make different enterprise and organization interchange trade and commercial datas through Computers in according with the standardized specification. Sinc...EDI is an abbreviation for Electronic Data Interchange. It can make different enterprise and organization interchange trade and commercial datas through Computers in according with the standardized specification. Since it can save various of documents,we also call it"paperless" operation. The development of information technique from primary to advanced, which computers had been used as main part,involves three stages: The first stage is that computers bad been used to replace man to process various of business and documents inside the enterprise. The second stage is the network sys-展开更多
With the application of new techniques, materials and technologies in West East Gas Transportation Pipeline (WEGTP) project, the design concept of domestic pipeline industrial construction has been updated, speeding u...With the application of new techniques, materials and technologies in West East Gas Transportation Pipeline (WEGTP) project, the design concept of domestic pipeline industrial construction has been updated, speeding up the development and improvement of the strength as a whole in aspects of smelting industry, pipe fabrication, pipeline construction and equipment manufacture,making China’s pipeline industry catch up with the trend of development of the world advanced level.展开更多
Short-term traffic flow prediction is one of the essential issues in intelligent transportation systems(ITS). A new two-stage traffic flow prediction method named AKNN-AVL method is presented, which combines an advanc...Short-term traffic flow prediction is one of the essential issues in intelligent transportation systems(ITS). A new two-stage traffic flow prediction method named AKNN-AVL method is presented, which combines an advanced k-nearest neighbor(AKNN)method and balanced binary tree(AVL) data structure to improve the prediction accuracy. The AKNN method uses pattern recognition two times in the searching process, which considers the previous sequences of traffic flow to forecast the future traffic state. Clustering method and balanced binary tree technique are introduced to build case database to reduce the searching time. To illustrate the effects of these developments, the accuracies performance of AKNN-AVL method, k-nearest neighbor(KNN) method and the auto-regressive and moving average(ARMA) method are compared. These methods are calibrated and evaluated by the real-time data from a freeway traffic detector near North 3rd Ring Road in Beijing under both normal and incident traffic conditions.The comparisons show that the AKNN-AVL method with the optimal neighbor and pattern size outperforms both KNN method and ARMA method under both normal and incident traffic conditions. In addition, the combinations of clustering method and balanced binary tree technique to the prediction method can increase the searching speed and respond rapidly to case database fluctuations.展开更多
The aim of this paper is to compare block-structured linear programming (LP) models against other practical optimization methods for solving downstream product refinery problems using a solution method different fro...The aim of this paper is to compare block-structured linear programming (LP) models against other practical optimization methods for solving downstream product refinery problems using a solution method different from the existing ones (like mixed integer linear programming (MILP) method). The work X-rays the Nigerian petroleum refining industries and their channel of distribution in the local setting and identifies the critical features of scheduling and allocation of refined crude products; either for distribution within the country or for exportation to the international market. Applying our model to the distribution model, the computational results reveal a better route with lowest transportation cost for the scheduling problem and the best optimal blend with higher revenue for the production problem.展开更多
It is a very complex and time-consuming process to simulate the nuclear reactor neutron spectrum from the reactor core to the export channel by applying a Monte Carlo program. This paper presents a new method to calcu...It is a very complex and time-consuming process to simulate the nuclear reactor neutron spectrum from the reactor core to the export channel by applying a Monte Carlo program. This paper presents a new method to calculate the neutron spectrum by using the convolution technique which considers the channel transportation as a linear system and the transportation scattering as the response function. It also applies Monte Carlo Neutron and Photon Transport Code (MCNP) to simulate the response function numerically. With the application of convolution technique to calculate the spectrum distribution from the core to the channel, the process is then much more convenient only with the simple numerical integral numeration. This saves computer time and reduces some trouble in re-writing of the MCNP program.展开更多
Forecasting travel demand requires a grasp of individual decision-making behavior.However,transport mode choice(TMC)is determined by personal and contextual factors that vary from person to person.Numerous characteris...Forecasting travel demand requires a grasp of individual decision-making behavior.However,transport mode choice(TMC)is determined by personal and contextual factors that vary from person to person.Numerous characteristics have a substantial impact on travel behavior(TB),which makes it important to take into account while studying transport options.Traditional statistical techniques frequently presume linear correlations,but real-world data rarely follows these presumptions,which may make it harder to grasp the complex interactions.Thorough systematic review was conducted to examine how machine learning(ML)approaches might successfully capture nonlinear correlations that conventional methods may ignore to overcome such challenges.An in-depth analysis of discrete choice models(DCM)and several ML algorithms,datasets,model validation strategies,and tuning techniques employed in previous research is carried out in the present study.Besides,the current review also summarizes DCM and ML models to predict TMC and recognize the determinants of TB in an urban area for different transport modes.The two primary goals of our study are to establish the present conceptual frameworks for the factors influencing the TMC for daily activities and to pinpoint methodological issues and limitations in previous research.With a total of 39 studies,our findings shed important light on the significance of considering factors that influence the TMC.The adjusted kernel algorithms and hyperparameter-optimized ML algorithms outperform the typical ML algorithms.RF(random forest),SVM(support vector machine),ANN(artificial neural network),and interpretable ML algorithms are the most widely used ML algorithms for the prediction of TMC where RF achieved an R2 of 0.95 and SVM achieved an accuracy of 93.18%;however,the adjusted kernel enhanced the accuracy of SVM 99.81%which shows that the interpretable algorithms outperformed the typical algorithms.The sensitivity analysis indicates that the most significant parameters influencing TMC are the age,total trip time,and the number of drivers.展开更多
: The “oxygen burst” phenomenon that appeared during the light-induction period of intact leaves could be monitored using a photoacoustic technique high time resolution. The relationship between oxygen bursts and da...: The “oxygen burst” phenomenon that appeared during the light-induction period of intact leaves could be monitored using a photoacoustic technique high time resolution. The relationship between oxygen bursts and dark-adapted time, far-red light pretreatment, photothermal signal, and chlorophyll a (Chl a) fluorescence kinetics were investigated in the present study. Using extraneous inhibitors or cofactors of electron transport, a modified vacuum-infiltration method was undertaken to locate directly the site at which oxygen bursts of intact leaves occurred. We found that the photothermal signal showed little evidence of oscillation during the light-induction period. The oxygen burst was resolved into two components if dark-adapted time lasted longer than 20 min. Methyl viologen (MV) or far-red light could not eliminate the first component, whereas formate-Na (pH 7.0,20 μmol/L) eliminated the first component but had no effect on the second one. Furthermore, the photochemical quenching, the electron transport rate of Chl a fluorescence, and the first component of the oxygen bursts approached lowest values simultaneously. This evidence indicates that the site at which the first component of oxygen bursts occurred was located between photo-system (PS)I and PSII (i.e. the PQ pool). The formate-Na experiment also showed a linkage between the first component and the S state of oxygen evolution at the donor side of PSII. Furthermore, elimination of the second component by far-red light and absorption of the second component by MV indicated that the site at which the second component of oxygen bursts may be located at the acceptor side of PSII.展开更多
Privacy and trust are significant issues in intelligent transportation systems(ITS).Data security is critical in ITS systems since sensitive user data is communicated to another user over the internet through wireless...Privacy and trust are significant issues in intelligent transportation systems(ITS).Data security is critical in ITS systems since sensitive user data is communicated to another user over the internet through wireless devices and routes such as radio channels,optical fiber,and blockchain technology.The Internet of Things(IoT)is a network of connected,interconnected gadgets.Privacy issues occasionally arise due to the amount of data generated.However,they have been primarily addressed by blockchain and smart contract technology.While there are still security issues with smart contracts,primarily due to the complexity of writing the code,there are still many challenges to consider when designing blockchain designs for the IoT environment.This study uses traditional blockchain technology with the“You Only Look Once”(YOLO)object detection method to accurately locate and identify license plates.While YOLO and blockchain technologies used for intelligent vehicle license plate recognition are promising,they have received limited research attention.Real-time object identification and recognition would be possible by combining a cutting-edge object detection technique with a regional convolutional neural network(RCNN)built with the tensor flow core open source libraries.This method works reasonably well for identifying any license plate.The Automatic License Plate Recognition(ALPR)approach delivered outstanding results in various datasets.First,with a recognition rate of 96.2%,our system(UFPR-ALPR)surpassed the previously used technology,consisting of 4500 frames and around 150 films.Second,a deep learning algorithm was trained to recognize images of license plate numbers using the UFPR-ALPR dataset.Third,the license plate’s characters were complicated for standard methods to identify because of the shifting lighting correctly.The proposed model,however,produced beneficial outcomes.展开更多
GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address th...GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address the question, first, 5’ Rapid amplification of cDNA end (RACE) was used to determine GAT1 transcriptional starting sites in neonatal mouse cerebral cortex and intestine, adult mouse brain and adult rat testis. The products of 5’RACE were confirmed by DNA sequencing. We found that the transcript of GAT1 in neonatal mouse cerebral cortex and adult mouse brain starts at the same site (inside of exon 1), while in mouse intestine, GAT1 starts transcription in intron 1, and in rat testis, the transcript of GAT1 has an additional untranslation exon to the 5’ direction.展开更多
The polarization effect introduced by electric field deformation is the most important bottleneck of CdZnTe detector in x-ray imaging. Currently, most of studies focus on electric field deformation caused by trapped c...The polarization effect introduced by electric field deformation is the most important bottleneck of CdZnTe detector in x-ray imaging. Currently, most of studies focus on electric field deformation caused by trapped carriers;the perturbation of electric field due to drifting carriers has been rarely reported. In this study, the effect of transient space-charge perturbation on carrier transport in a CdZnTe semiconductor is evaluated by using the laser-beam-induced current(LBIC) technique.Cusps appear in the current curves of CdZnTe detectors with different carrier transport performances under intense excitation, indicating the deformation of electric field. The current signals under different excitations are compared. The results suggest that with the increase of excitation, the amplitude of cusp increases and the electron transient time gradually decreases. The distortion in electric field is independent of carrier transport performance of detector. Transient space-charge perturbation is responsible for the pulse shape and affects the carrier transport process.展开更多
This paper investigates the transverse 3:1 internal resonance of an axially transporting nonlinear viscoelastic Euler-Bernoulli beam with a two-frequency parametric excitation caused by a speed perturbation.The Kelvin...This paper investigates the transverse 3:1 internal resonance of an axially transporting nonlinear viscoelastic Euler-Bernoulli beam with a two-frequency parametric excitation caused by a speed perturbation.The Kelvin-Voigt model is introduced to describe the viscoelastic characteristics of the axially transporting beam.The governing equation and the associated boundary conditions are obtained by Newton’s second law.The method of multiple scales is utilized to obtain the steady-state responses.The RouthHurwitz criterion is used to determine the stabilities and bifurcations of the steady-state responses.The effects of the material viscoelastic coefficient on the dynamics of the transporting beam are studied in detail by a series of numerical demonstrations.Interesting phenomena of the steady-state responses are revealed in the 3:1 internal resonance and two-frequency parametric excitation.The approximate analytical method is validated via a differential quadrature method.展开更多
In this paper a fuzzy transportation problem under a fuzzy environment is solved using octagonal fuzzy numbers.The transportation problem is significant and has been widely studied in the field of applied mathematics ...In this paper a fuzzy transportation problem under a fuzzy environment is solved using octagonal fuzzy numbers.The transportation problem is significant and has been widely studied in the field of applied mathematics to solve a system of linear equations in many applications in science.Systems of concurrent linear equations play a vital major role in operational research.The main perspective of this research paper is to find out the minimum amount of transportation cost of some supplies through a capacitated network formerly the availability and the demand notes are octagonal fuzzy numbers.Octagonal fuzzy numbers are used and showed a membership function.To illustrate this method,a fuzzy transportation problem is solved by using octagonal fuzzy numbers using the ranking technique.It is shown that it is the best optimal solution and it is demonstrated with a numerical example.展开更多
基金Supported by the Major State Basic Research Program (No. G1999043810) Open Laboratory for Tropical Marine Environmental Dynamics (LED)+2 种基金 South China Sea Institute of Oceanology Chinese Academy of Sciences and the NSFC (No. 40306004).
文摘A P-vector method was optimized using variational data assimilation technique, with which the vertical structures and seasonal variations of zonal velocities and transports were investigated. The results showed that westward and eastward flowes occur in the Luzon Strait in the same period in a year. However the net volume transport is westward. In the upper level (0m -500m),the westward flow exits in the middle and south of the Luzon Strait, and the eastward flow exits in the north. There are two centers of westward flow and one center of eastward flow. In the middle of the Luzon Strait, westward and eastward flowes appear alternately in vertical direction. The westward flow strengthens in winter and weakens in summer. The net volume transport is strong in winter (5.53 Sv) but weak in summer (0.29 Sv). Except in summer, the volume transport in the upper level accounts for more than half of the total volume transport (0m bottom). In summer, the net volume transport in the upper level is eastward (1.01 Sv), but westward underneath.
文摘BACKGROUND The Ilizarov bone transport(IBT)and the Masquelet induced membrane technique(IMT)have specific merits and shortcomings,but numerous studies have shown their efficacy in the management of extensive long-bone defects of various etiologies,including congenital deficiencies.Combining their strong benefits seems a promising strategy to enhance bone regeneration and reduce the risk of refractures in the management of post-traumatic and congenital defects and nonunion that failed to respond to other treatments.AIM To combine IBT and IMT for the management of severe tibial defects and pseudarthrosis,and present preliminary results of this technological solution.METHODS Seven adults with post-traumatic tibial defects(subgroup A)and nine children(subgroup B)with congenital pseudarthrosis of the tibia(CPT)were treated with the combination of IMT and IBT after the failure of previous treatments.The mean number of previous surgeries was 2.0±0.2 in subgroup A and 3.3±0.7 in subgroup B.Step 1 included Ilizarov frame placement and spacer introduction into the defect to generate the induced membrane which remained in the interfragmental gap after spacer removal.Step 2 was an osteotomy and bone transport of the fragment through the tunnel in the induced membrane,its compression and docking for consolidation without grafting.The outcomes were retrospectively studied after a mean follow-up of 20.8±2.7 mo in subgroup A and 25.3±2.3 mo in subgroup B.RESULTS The“true defect”after resection was 13.3±1.7%in subgroup A and 31.0±3.0%in subgroup B relative to the contralateral limb.Upon completion of treatment,defects were filled by 75.4±10.6%and 34.6±4.2%,respectively.Total duration of external fixation was 397±9.2 and 270.1±16.3 d,including spacer retention time of 42.4±4.5 and 55.8±6.6 d,in subgroups A and B,respectively.Bone infection was not observed.Postoperative complications were several cases of pin-tract infection and regenerate deformity in both subgroups.Ischemic regeneration was observed in two cases of subgroup B.Complications were corrected during the course of treatment.Bone union was achieved in all patients of subgroup A and in seven patients of subgroup B.One non-united CPT case was further treated with the Ilizarov compression method only and achieved union.After a follow-up period of two to three years,refractures occurred in four cases of united CPT.CONCLUSION The combination of IMT and IBT provides good outcomes in post-traumatic tibial defects after previous treatment failure but external fixation is longer due to spacer retention.Refractures may occur in severe CPT.
基金supported by the National Key R&D Program of China(No.2017YFC0307800-05).
文摘The transport cross-section based on inflow transport approximation can significantly improve the accuracy of light water reactor(LWR)analysis,especially for the treatment of the anisotropic scattering effect.The previous inflow transport approximation is based on the moderator cross-section and normalized fission source,which is approximated using transport theory.Although the accuracy of reactivity is increased,the P0 flux moment has a large error in the Monte Carlo code.In this study,an improved inflow transport approximation was introduced with homogenization techniques,applying the homogenized cross-section and accurate fission source.The numerical results indicated that the improved inflow transport approximation can increase the P0 flux moment accuracy and maintain the reactivity calculation precision with the previous inflow transport approximation in typical LWR cases.In addition to this investigation,the improved inflow transport approximation is related to the temperature factors.The improved inflow transport approximation is flexible and accurate in the treatment of the anisotropic scattering effect,which can be directly used in the temperature-dependent nuclear data library.
文摘Large-sized (~2 inch, 50.8 mm) γ-LiAlO2 single crystal has been grown by conventional Czochralski (Cz) method, but the crystal has a milky, dendriform center. The samples taken from transparent and milky parts were ground and examined by X-ray diffraction. All diffraction peaks could be indexed in γ-LiAlO2. The crystal quality was characterized by X-ray rocking curve. The full-width at half-maximum (FWHM) values are 116.9 and 132.0 arcsec for transparent and milky parts, respectively. The vapor transport equilibrium (VTE) technique was introduced to modify the crystal quality. After 1000℃/48 h, 1100℃/48 h, 1200℃/48 h VTE processes, the FWHM values dropped to 44.2 and 55.2 arcsec for transparent and milky part, respectively. The optical transmission of transparent part was greatly enhanced from 85% to 90%, and transmission of milky part from 75% to 80% in the range of 190~1900 nm at room temperature. When the VTE temperature was raised to 1300℃, the sample cracked and FWHM values of transparent and milky parts were increased to 55.2 and 80.9 arcsec, respectively. By combining Cz technique with VTE technique, large-sized and high quality γ-LiAlO2 crystal can be obtained.
文摘Most drug products on the global pharmaceutical market are administered orally.The absorption of oral drug in the intestine is an important factor to determine the drug bioavailability.There are many intestinal transporters expressed on the small intestine and the transporters can be classified into two major families,SLC family and ABC family.They mediate drug absorption,distribution,excretion and drugedrug interaction.Understanding the transport mechanism can improve the effectivity and safety of drug and guide clinical rational use of drugs.The roles of drug transporters can be assessed in vitro and in vivo,using techniques spanning from cellular expression systems to gene knockout animals.The purposes of this article were to introduce the main transporters in the intestinal tract,to explain the transport mechanism and to compare the limitations and applications of techniques used to evaluate interactions of drugs and transporters.
文摘EDI is an abbreviation for Electronic Data Interchange. It can make different enterprise and organization interchange trade and commercial datas through Computers in according with the standardized specification. Since it can save various of documents,we also call it"paperless" operation. The development of information technique from primary to advanced, which computers had been used as main part,involves three stages: The first stage is that computers bad been used to replace man to process various of business and documents inside the enterprise. The second stage is the network sys-
文摘With the application of new techniques, materials and technologies in West East Gas Transportation Pipeline (WEGTP) project, the design concept of domestic pipeline industrial construction has been updated, speeding up the development and improvement of the strength as a whole in aspects of smelting industry, pipe fabrication, pipeline construction and equipment manufacture,making China’s pipeline industry catch up with the trend of development of the world advanced level.
基金Project(2012CB725403)supported by the National Basic Research Program of ChinaProjects(71210001,51338008)supported by the National Natural Science Foundation of ChinaProject supported by World Capital Cities Smooth Traffic Collaborative Innovation Center and Singapore National Research Foundation Under Its Campus for Research Excellence and Technology Enterprise(CREATE)Programme
文摘Short-term traffic flow prediction is one of the essential issues in intelligent transportation systems(ITS). A new two-stage traffic flow prediction method named AKNN-AVL method is presented, which combines an advanced k-nearest neighbor(AKNN)method and balanced binary tree(AVL) data structure to improve the prediction accuracy. The AKNN method uses pattern recognition two times in the searching process, which considers the previous sequences of traffic flow to forecast the future traffic state. Clustering method and balanced binary tree technique are introduced to build case database to reduce the searching time. To illustrate the effects of these developments, the accuracies performance of AKNN-AVL method, k-nearest neighbor(KNN) method and the auto-regressive and moving average(ARMA) method are compared. These methods are calibrated and evaluated by the real-time data from a freeway traffic detector near North 3rd Ring Road in Beijing under both normal and incident traffic conditions.The comparisons show that the AKNN-AVL method with the optimal neighbor and pattern size outperforms both KNN method and ARMA method under both normal and incident traffic conditions. In addition, the combinations of clustering method and balanced binary tree technique to the prediction method can increase the searching speed and respond rapidly to case database fluctuations.
文摘The aim of this paper is to compare block-structured linear programming (LP) models against other practical optimization methods for solving downstream product refinery problems using a solution method different from the existing ones (like mixed integer linear programming (MILP) method). The work X-rays the Nigerian petroleum refining industries and their channel of distribution in the local setting and identifies the critical features of scheduling and allocation of refined crude products; either for distribution within the country or for exportation to the international market. Applying our model to the distribution model, the computational results reveal a better route with lowest transportation cost for the scheduling problem and the best optimal blend with higher revenue for the production problem.
文摘It is a very complex and time-consuming process to simulate the nuclear reactor neutron spectrum from the reactor core to the export channel by applying a Monte Carlo program. This paper presents a new method to calculate the neutron spectrum by using the convolution technique which considers the channel transportation as a linear system and the transportation scattering as the response function. It also applies Monte Carlo Neutron and Photon Transport Code (MCNP) to simulate the response function numerically. With the application of convolution technique to calculate the spectrum distribution from the core to the channel, the process is then much more convenient only with the simple numerical integral numeration. This saves computer time and reduces some trouble in re-writing of the MCNP program.
文摘Forecasting travel demand requires a grasp of individual decision-making behavior.However,transport mode choice(TMC)is determined by personal and contextual factors that vary from person to person.Numerous characteristics have a substantial impact on travel behavior(TB),which makes it important to take into account while studying transport options.Traditional statistical techniques frequently presume linear correlations,but real-world data rarely follows these presumptions,which may make it harder to grasp the complex interactions.Thorough systematic review was conducted to examine how machine learning(ML)approaches might successfully capture nonlinear correlations that conventional methods may ignore to overcome such challenges.An in-depth analysis of discrete choice models(DCM)and several ML algorithms,datasets,model validation strategies,and tuning techniques employed in previous research is carried out in the present study.Besides,the current review also summarizes DCM and ML models to predict TMC and recognize the determinants of TB in an urban area for different transport modes.The two primary goals of our study are to establish the present conceptual frameworks for the factors influencing the TMC for daily activities and to pinpoint methodological issues and limitations in previous research.With a total of 39 studies,our findings shed important light on the significance of considering factors that influence the TMC.The adjusted kernel algorithms and hyperparameter-optimized ML algorithms outperform the typical ML algorithms.RF(random forest),SVM(support vector machine),ANN(artificial neural network),and interpretable ML algorithms are the most widely used ML algorithms for the prediction of TMC where RF achieved an R2 of 0.95 and SVM achieved an accuracy of 93.18%;however,the adjusted kernel enhanced the accuracy of SVM 99.81%which shows that the interpretable algorithms outperformed the typical algorithms.The sensitivity analysis indicates that the most significant parameters influencing TMC are the age,total trip time,and the number of drivers.
文摘: The “oxygen burst” phenomenon that appeared during the light-induction period of intact leaves could be monitored using a photoacoustic technique high time resolution. The relationship between oxygen bursts and dark-adapted time, far-red light pretreatment, photothermal signal, and chlorophyll a (Chl a) fluorescence kinetics were investigated in the present study. Using extraneous inhibitors or cofactors of electron transport, a modified vacuum-infiltration method was undertaken to locate directly the site at which oxygen bursts of intact leaves occurred. We found that the photothermal signal showed little evidence of oscillation during the light-induction period. The oxygen burst was resolved into two components if dark-adapted time lasted longer than 20 min. Methyl viologen (MV) or far-red light could not eliminate the first component, whereas formate-Na (pH 7.0,20 μmol/L) eliminated the first component but had no effect on the second one. Furthermore, the photochemical quenching, the electron transport rate of Chl a fluorescence, and the first component of the oxygen bursts approached lowest values simultaneously. This evidence indicates that the site at which the first component of oxygen bursts occurred was located between photo-system (PS)I and PSII (i.e. the PQ pool). The formate-Na experiment also showed a linkage between the first component and the S state of oxygen evolution at the donor side of PSII. Furthermore, elimination of the second component by far-red light and absorption of the second component by MV indicated that the site at which the second component of oxygen bursts may be located at the acceptor side of PSII.
基金extend their appreciation to the deanship of scientific research at Shaqra University for funding this research work through the Project Number(SU-ANN-202248).
文摘Privacy and trust are significant issues in intelligent transportation systems(ITS).Data security is critical in ITS systems since sensitive user data is communicated to another user over the internet through wireless devices and routes such as radio channels,optical fiber,and blockchain technology.The Internet of Things(IoT)is a network of connected,interconnected gadgets.Privacy issues occasionally arise due to the amount of data generated.However,they have been primarily addressed by blockchain and smart contract technology.While there are still security issues with smart contracts,primarily due to the complexity of writing the code,there are still many challenges to consider when designing blockchain designs for the IoT environment.This study uses traditional blockchain technology with the“You Only Look Once”(YOLO)object detection method to accurately locate and identify license plates.While YOLO and blockchain technologies used for intelligent vehicle license plate recognition are promising,they have received limited research attention.Real-time object identification and recognition would be possible by combining a cutting-edge object detection technique with a regional convolutional neural network(RCNN)built with the tensor flow core open source libraries.This method works reasonably well for identifying any license plate.The Automatic License Plate Recognition(ALPR)approach delivered outstanding results in various datasets.First,with a recognition rate of 96.2%,our system(UFPR-ALPR)surpassed the previously used technology,consisting of 4500 frames and around 150 films.Second,a deep learning algorithm was trained to recognize images of license plate numbers using the UFPR-ALPR dataset.Third,the license plate’s characters were complicated for standard methods to identify because of the shifting lighting correctly.The proposed model,however,produced beneficial outcomes.
基金foundations from Chinese Academy of Sciences and Special Funds for Major State Basic reseaxch of China (G1999053903).
文摘GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address the question, first, 5’ Rapid amplification of cDNA end (RACE) was used to determine GAT1 transcriptional starting sites in neonatal mouse cerebral cortex and intestine, adult mouse brain and adult rat testis. The products of 5’RACE were confirmed by DNA sequencing. We found that the transcript of GAT1 in neonatal mouse cerebral cortex and adult mouse brain starts at the same site (inside of exon 1), while in mouse intestine, GAT1 starts transcription in intron 1, and in rat testis, the transcript of GAT1 has an additional untranslation exon to the 5’ direction.
基金Project supported by the National Natural Science Foundation of China(Grant No.61874089)the Fund of MIIT(Grant No.MJ-2017-F-05)+2 种基金the 111 Project of China(Grant No.B08040)the NPU Foundation for Fundamental Research,Chinathe Research Found of the State Key Laboratory of Solidification Processing(NWPU),China
文摘The polarization effect introduced by electric field deformation is the most important bottleneck of CdZnTe detector in x-ray imaging. Currently, most of studies focus on electric field deformation caused by trapped carriers;the perturbation of electric field due to drifting carriers has been rarely reported. In this study, the effect of transient space-charge perturbation on carrier transport in a CdZnTe semiconductor is evaluated by using the laser-beam-induced current(LBIC) technique.Cusps appear in the current curves of CdZnTe detectors with different carrier transport performances under intense excitation, indicating the deformation of electric field. The current signals under different excitations are compared. The results suggest that with the increase of excitation, the amplitude of cusp increases and the electron transient time gradually decreases. The distortion in electric field is independent of carrier transport performance of detector. Transient space-charge perturbation is responsible for the pulse shape and affects the carrier transport process.
基金Project supported by the National Natural Science Foundation of China (Nos.12002142,1187215951976087)+1 种基金the National Natural Science Foundation of Shanghai of China (No.21ZR1462500)the Natural Science Foundation of Shandong Province of China (No.ZR2021QB137)。
文摘This paper investigates the transverse 3:1 internal resonance of an axially transporting nonlinear viscoelastic Euler-Bernoulli beam with a two-frequency parametric excitation caused by a speed perturbation.The Kelvin-Voigt model is introduced to describe the viscoelastic characteristics of the axially transporting beam.The governing equation and the associated boundary conditions are obtained by Newton’s second law.The method of multiple scales is utilized to obtain the steady-state responses.The RouthHurwitz criterion is used to determine the stabilities and bifurcations of the steady-state responses.The effects of the material viscoelastic coefficient on the dynamics of the transporting beam are studied in detail by a series of numerical demonstrations.Interesting phenomena of the steady-state responses are revealed in the 3:1 internal resonance and two-frequency parametric excitation.The approximate analytical method is validated via a differential quadrature method.
文摘In this paper a fuzzy transportation problem under a fuzzy environment is solved using octagonal fuzzy numbers.The transportation problem is significant and has been widely studied in the field of applied mathematics to solve a system of linear equations in many applications in science.Systems of concurrent linear equations play a vital major role in operational research.The main perspective of this research paper is to find out the minimum amount of transportation cost of some supplies through a capacitated network formerly the availability and the demand notes are octagonal fuzzy numbers.Octagonal fuzzy numbers are used and showed a membership function.To illustrate this method,a fuzzy transportation problem is solved by using octagonal fuzzy numbers using the ranking technique.It is shown that it is the best optimal solution and it is demonstrated with a numerical example.