In recent years,railway construction in China has developed vigorously.With continuous improvements in the highspeed railway network,the focus is gradually shifting from large-scale construction to large-scale operati...In recent years,railway construction in China has developed vigorously.With continuous improvements in the highspeed railway network,the focus is gradually shifting from large-scale construction to large-scale operations.However,several challenges have emerged within the high-speed railway dispatching and command system,including the heavy workload faced by dispatchers,the difficulty of quantifying subjective expertise,and the need for effective training of professionals.Amid the growing application of artificial intelligence technologies in railway systems,this study leverages Large Language Model(LLM)technology.LLMs bring enhanced intelligence,predictive capabilities,robust memory,and adaptability to diverse real-world scenarios.This study proposes a human-computer interactive intelligent scheduling auxiliary training system built on LLM technology.The system offers capabilities including natural dialogue,knowledge reasoning,and human feedback learning.With broad applicability,the system is suitable for vocational education,guided inquiry,knowledge-based Q&A,and other training scenarios.Validation results demonstrate its effectiveness in auxiliary training,providing substantial support for educators,students,and dispatching personnel in colleges and professional settings.展开更多
Background:This study evaluates the ability of mobile AI voice assistants(AI-VAs)to provide accurate medical advice for early knee osteoarthritis(KOA)and compares their performance with conventional web searches and h...Background:This study evaluates the ability of mobile AI voice assistants(AI-VAs)to provide accurate medical advice for early knee osteoarthritis(KOA)and compares their performance with conventional web searches and human clinicians.Methods:From September to October 2024,two AI-VAs(Apple’s Siri and Huawei’s Xiaoyi)were tested on 15 KOA-related questions in Chinese and English.The assessment focused on the accuracy of voice recognition,response capabilities,and medical advice.Siri was further tested in four international regions(USA,UK,Germany,Hong Kong)using localized languages.Results:In Chinese-language tests,Siri and Xiaoyi showed comparable voice recognition(recognition accuracy:95.6%vs.93.3%)and response ability(speech response:88.9%vs.85.7%).However,Siri provided significantly more accurate medical advice(medical advice:95.6%vs.53.3%;Z=2.762,P<0.001).External validation via Global Quality Score further confirmed Siri’s superiority(mean Global Quality Score=4.0 vs.Xiaoai=0.9).Siri outperformed Xiaoyi in English-language tests(53.3%vs.0%).While Siri’s medical advice accuracy(95.6%)surpassed non-specialist clinicians(Z=2.685,P=0.007),it primarily reflects filtered search results(Baidu/Google)rather than clinical synthesis.Claims of equivalence to junior surgeons(98.2%)must be interpreted cautiously,as AI-VAs lack diagnostic reasoning capabilities.This distinction is critical to avoid overstating their role in clinical decision-making.Conclusion:Current AI-VAs offer limited value in providing precise medical advice for KOA,primarily serving as intermediaries for web search results.Their performance varies across languages,regions,and search engines.展开更多
This study analyzed how impressions are formed online depending on the type of social media and the implications that may come from the over-disclosure of information. Using a Qualtrics survey, 97 participants viewed ...This study analyzed how impressions are formed online depending on the type of social media and the implications that may come from the over-disclosure of information. Using a Qualtrics survey, 97 participants viewed the profile of a female teaching assistant on Twitter and Facebook. While there was little difference between the two social media, the use of self-disclosure on Twitter seemed slightly more inappropriate for sharing personal information.展开更多
Background:Work engagement(WE)is critical to quality primary healthcare delivery.However,limited research has explored its levels and determinants among healthcare professionals in low-and middle-income countries.This...Background:Work engagement(WE)is critical to quality primary healthcare delivery.However,limited research has explored its levels and determinants among healthcare professionals in low-and middle-income countries.This study assessed the levels and correlates of work engagement among physician assistants(PAs)in Ghana.Methods:A cross-sectional study was conducted among 439 PAs from October to December 2024.Participants were recruited via emails,social media platforms,and posters featuring study links and scannable questionnaire codes.WE was measured using the validated Utrecht Work Engagement Scale questionnaire.Results:Overall,WE levels were average,with similar trends across the three subdomains.In the bootstrapped multivariate linear regression model,anxiety was negatively associated with WE(β=-0.49,95%confidence interval[CI]:-0.77 to-0.21).Conversely,working in an urban area(β=0.36,95%CI:0.05 to 0.67),holding the rank of PA/Senior PA(β=0.27,95%CI:0.03 to 0.52),reporting good self-rated health(β=0.54,95%CI:0.19 to 0.88),and working at health centers(β=0.86,95%CI:0.22 to 1.50)were positively associated with WElevels.Conclusion:WE levels are average in the study sample,highlighting the need for strategic interventions to improve and sustain the healthcare workforce's motivation and performance.Addressing workplace stressors,enhancing professional development opportunities,and fostering supportive work environments could improve engagement among PAs and healthcare professionals in general.Strengthening WE is essential for ensuring resilient quality primary healthcare systems and achieving the goals of universal health coverage.展开更多
Intelligent personal assistants play a pivotal role in in-vehicle systems,significantly enhancing life efficiency,driving safety,and decision-making support.In this study,the multi-modal design elements of intelligent...Intelligent personal assistants play a pivotal role in in-vehicle systems,significantly enhancing life efficiency,driving safety,and decision-making support.In this study,the multi-modal design elements of intelligent personal assistants within the context of visual,auditory,and somatosensory interactions with drivers were discussed.Their impact on the driver’s psychological state through various modes such as visual imagery,voice interaction,and gesture interaction were explored.The study also introduced innovative designs for in-vehicle intelligent personal assistants,incorporating design principles such as driver-centricity,prioritizing passenger safety,and utilizing timely feedback as a criterion.Additionally,the study employed design methods like driver behavior research and driving situation analysis to enhance the emotional connection between drivers and their vehicles,ultimately improving driver satisfaction and trust.展开更多
This article examines the implementation of a virtual health assistant powered by Retrieval-Augmented Generation (RAG) and GPT-4, aimed at enhancing clinical support through personalized, real-time interactions with p...This article examines the implementation of a virtual health assistant powered by Retrieval-Augmented Generation (RAG) and GPT-4, aimed at enhancing clinical support through personalized, real-time interactions with patients. The system is hypothesized to improve healthcare accessibility, operational efficiency, and patient outcomes by automating routine tasks and delivering accurate health information. The assistant leverages natural language processing and real-time data retrieval models to respond to patient inquiries, schedule appointments, provide medication reminders, assist with symptom triage, and answer insurance-related questions. By integrating RAG-based virtual care, the system reduces the burden on healthcare specialists and helps mitigate healthcare disparities, particularly in rural areas where traditional care is limited. Although the initial scope of testing did not validate all potential benefits, the results demonstrated high patient satisfaction and strong response accuracy, both critical for systems of this nature. These findings underscore the transformative potential of AI-driven virtual health assistants in enhancing patient engagement, streamlining operational workflows, and improving healthcare accessibility, ultimately contributing to better outcomes and more cost-effective care delivery.展开更多
Conceptual design, data model and key techniques of "Geo-engineer 3D assistant", an underground 3D GIS oriented to geology and mine application, were discussed. In particular, the importance of high-order sm...Conceptual design, data model and key techniques of "Geo-engineer 3D assistant", an underground 3D GIS oriented to geology and mine application, were discussed. In particular, the importance of high-order smoothing triangular pieces to surface's fine expression in geological modeling was emphasized. The contour mode is the most favorite mode of the three modes about surface expression: DEM, TIN and contour. Topology in underground 3D modeling with CAGD was compared. From the view of boundary and coboundary, which is soul of IS 19107 (Geographic information spatial schema), 3D underground topology was re-examined.展开更多
Nano SiO2/NR composites were prepared through blending nano SiO2 emulsion with natural rubber latex and then concreting with acetic acid. The emulsion nano SiO2 was prepared with Na2SiO3-9H2O and hydrochloric acid und...Nano SiO2/NR composites were prepared through blending nano SiO2 emulsion with natural rubber latex and then concreting with acetic acid. The emulsion nano SiO2 was prepared with Na2SiO3-9H2O and hydrochloric acid under the reaction of the assistant agents. The was analyzed effect of the application rates of assistant agents such as silane coupling agent, surfactant, nucleating agent and dispersant on the properties and interface structure of the nano SiO2/NR composites with IR, TEM, SEM, DMA was analyzed. An orthogonal test was arranged to select optimum condition. The results show that the best combination for preparing nano SiO2/NR composites is as follows： the rate of the silane coupling agent （TESPT）, the surfactant（dodecyl benzene sulfonate natrium）, nucleating agent（AlCl3） and dispersant（ethylene diamine tetraacetie acid） in the course of preparing nano SiO2 are 15%, 2.0%, 2.5% and 0.4%, respectively. Several replications in the experiment had produced desirable nano SiO2 products and nano SiO2/NR composites with better properties.展开更多
The laparoendoscopic single-site （LESS） technique is the latest technical innovation in laparoscopic surgery to undergo exponential development in urology. This study undertaken to illustrate our initial experience ...The laparoendoscopic single-site （LESS） technique is the latest technical innovation in laparoscopic surgery to undergo exponential development in urology. This study undertaken to illustrate our initial experience LESS radical prostatectomy （RP） and analyze early outcomes. Nineteen patients diagnosed with prostate cancer underwent LESS-RP in our institute. The patients were divided into two groups： conventional LESS and transurethral assistant LESS. Preoperative, perioperative, postoperative, pathologic, and functional outcomes data were assessed. With the help of a transurethral assistant, the mean operation and anastomosis time were decreased markedly. No focal positive margins were encountered. No prostate-specific antigen recurrence was detected 1 month postoperatively. Complete continence recovery （no pad） was observed in 32% of the patients at 1 month after the operation. No intraoperative and postoperative complications were reported, LESS-RP is a feasible and effective surgical procedure for treatment of prostate cancer. Moreover, transurethral assistant LESS could reduce the difficulty of LESS-RP and shorten the operation time.展开更多
Cocatalysts play a vital role in accelerating the reaction kinetics and improving the charge separation of photocatalysts for solar hydrogen production.The promotion of the photocatalytic activity largely relies on th...Cocatalysts play a vital role in accelerating the reaction kinetics and improving the charge separation of photocatalysts for solar hydrogen production.The promotion of the photocatalytic activity largely relies on the loading approach of the cocatalysts.Herein,we introduce a metal-seed assistant photodeposition approach to load the hydrogen evolution cocatalyst of platinum onto the surface of Ta_(3)N_(5) photocatalyst,which exhibits about 3.6 times of higher photocatalytic proton reduction activity with respect to the corresponding impregnation or photodeposition loading.Based on our characterizations,the increscent contact area of the cocatalyst/semiconductor interface with metal-seed assistant photodeposition method is proposed to be responsible for the promoted charge separation as well as enhanced photocatalytic H2 evolution activity.It is interesting to note that this innovative deposition strategy can be easily extended to loading of platinum cocatalyst with other noble or non-noble metal seeds for promoted activities,demonstrating its good generality.Our work may provide an alternative way of depositing cocatalyst for better photocatalytic performances.展开更多
Stealth security has always been considered as an important guarantee for the vitality and combat effectiveness of submarines.In accordance with the stealth requirements of submarines performing stealth voyage tasks,t...Stealth security has always been considered as an important guarantee for the vitality and combat effectiveness of submarines.In accordance with the stealth requirements of submarines performing stealth voyage tasks,this paper proposes a stealth assistant decision system.Firstly,the submarine stealth posture is acquired.A fuzzy neural network inference engine based on improved simplified particle swarm optimization is designed.The auxiliary decision-making scheme for state control and maneuver avoidance of submarine and its equipment is automatically generated.Secondly,the simulation and deduction of the assistant decision-making scheme are realized by the calculation modules of sound source level,propagation loss,and stealth situation.The assistant decision-making scheme and simulation result provide decision support for the commander.Thirdly,the simulation experiment platform of the submarine stealth assistant decision system is constructed.The submarine stealth assistant decision system described in this paper can quickly and efficiently produce assistant decision-making schemes,including submarine and equipment control and maneuver avoidance.The scheme is in line with the combat experience and the results of the pre-model simulation experiments,whereas the simulation deduction evaluates the rationality and effectiveness of the selected scheme.The submarine stealth assistant decision system can adapt to a complex battlefield environment in addition to rapidly and accurately providing assistance in decision-making.展开更多
Sutong Bridge is a cable-stayed steel box girder bridge with a main span of 1 088 m. The erection of upper structure adopts geometry control method and requires no change to the unit＇ s size and the structure＇ s non...Sutong Bridge is a cable-stayed steel box girder bridge with a main span of 1 088 m. The erection of upper structure adopts geometry control method and requires no change to the unit＇ s size and the structure＇ s none-stress geometry. Before main span closure, the cantilever of girder reaches 540.8 m, the structure state is noticeably influenced by extemal circumstances, the main span closure face great difficulty. By abstracting the advantage of the pullback method abroad and the domestic temperature-cutting method, a new assistant pullback method have put forward and bring into practice actually. In this paper, the analysis key point of practice conditions, key parameter of practice, main measures of the method and the performance is introduced.展开更多
A slow bromination process of butyl rubber （IIR） suffers from low efficiency and low selectivity （S） of target-product. To obtain suitable approach to intensify the process, effects of assistant solvents and mixin...A slow bromination process of butyl rubber （IIR） suffers from low efficiency and low selectivity （S） of target-product. To obtain suitable approach to intensify the process, effects of assistant solvents and mixing inten-sity on the bromination process were systemically studied in this paper. The reaction process was found constantly accelerated with the increasing dosage and polarity of assistant solvent. Hexane with 30%（by volume） dichloro-methane was found as the suitable solvent component, where the stable conversion of 1,4-isoprene transferring to target product （xA1s） of 80.2%and the corresponding S of 91.2%were obtained in 5 min. The accelerated reaction process was demonstrated being remarkably affected by mixing intensity until the optimal stirring rate of 1100 r＆#183;min-1 in a stirred tank reactor. With better mixing condition, a further intensification of the process was achieved in a ro-tating packed bed （RPB） reactor, where xA1s of 82.6% and S of 91.9% were obtained in 2 min. The usage of the suitable solvent component and RPB has potential application in the industrial bromination process intensification.展开更多
The first mid-term election of the U. S. in the new century took place on November 5, 2002. One third of the senators from the 107th Congress (34 out of 100), all representatives (435), 36 state governors, and numerou...The first mid-term election of the U. S. in the new century took place on November 5, 2002. One third of the senators from the 107th Congress (34 out of 100), all representatives (435), 36 state governors, and numerous local officials and legislators were to be elected or reelected. The resounding victory of the GOP in the congressional elections and the fact that the Democrats only got three more.展开更多
基金the Talent Fund of Beijing Jiaotong University(Grant No.2024XKRC055).
文摘In recent years,railway construction in China has developed vigorously.With continuous improvements in the highspeed railway network,the focus is gradually shifting from large-scale construction to large-scale operations.However,several challenges have emerged within the high-speed railway dispatching and command system,including the heavy workload faced by dispatchers,the difficulty of quantifying subjective expertise,and the need for effective training of professionals.Amid the growing application of artificial intelligence technologies in railway systems,this study leverages Large Language Model(LLM)technology.LLMs bring enhanced intelligence,predictive capabilities,robust memory,and adaptability to diverse real-world scenarios.This study proposes a human-computer interactive intelligent scheduling auxiliary training system built on LLM technology.The system offers capabilities including natural dialogue,knowledge reasoning,and human feedback learning.With broad applicability,the system is suitable for vocational education,guided inquiry,knowledge-based Q&A,and other training scenarios.Validation results demonstrate its effectiveness in auxiliary training,providing substantial support for educators,students,and dispatching personnel in colleges and professional settings.
文摘Background:This study evaluates the ability of mobile AI voice assistants(AI-VAs)to provide accurate medical advice for early knee osteoarthritis(KOA)and compares their performance with conventional web searches and human clinicians.Methods:From September to October 2024,two AI-VAs(Apple’s Siri and Huawei’s Xiaoyi)were tested on 15 KOA-related questions in Chinese and English.The assessment focused on the accuracy of voice recognition,response capabilities,and medical advice.Siri was further tested in four international regions(USA,UK,Germany,Hong Kong)using localized languages.Results:In Chinese-language tests,Siri and Xiaoyi showed comparable voice recognition(recognition accuracy:95.6%vs.93.3%)and response ability(speech response:88.9%vs.85.7%).However,Siri provided significantly more accurate medical advice(medical advice:95.6%vs.53.3%;Z=2.762,P<0.001).External validation via Global Quality Score further confirmed Siri’s superiority(mean Global Quality Score=4.0 vs.Xiaoai=0.9).Siri outperformed Xiaoyi in English-language tests(53.3%vs.0%).While Siri’s medical advice accuracy(95.6%)surpassed non-specialist clinicians(Z=2.685,P=0.007),it primarily reflects filtered search results(Baidu/Google)rather than clinical synthesis.Claims of equivalence to junior surgeons(98.2%)must be interpreted cautiously,as AI-VAs lack diagnostic reasoning capabilities.This distinction is critical to avoid overstating their role in clinical decision-making.Conclusion:Current AI-VAs offer limited value in providing precise medical advice for KOA,primarily serving as intermediaries for web search results.Their performance varies across languages,regions,and search engines.
文摘This study analyzed how impressions are formed online depending on the type of social media and the implications that may come from the over-disclosure of information. Using a Qualtrics survey, 97 participants viewed the profile of a female teaching assistant on Twitter and Facebook. While there was little difference between the two social media, the use of self-disclosure on Twitter seemed slightly more inappropriate for sharing personal information.
文摘Background:Work engagement(WE)is critical to quality primary healthcare delivery.However,limited research has explored its levels and determinants among healthcare professionals in low-and middle-income countries.This study assessed the levels and correlates of work engagement among physician assistants(PAs)in Ghana.Methods:A cross-sectional study was conducted among 439 PAs from October to December 2024.Participants were recruited via emails,social media platforms,and posters featuring study links and scannable questionnaire codes.WE was measured using the validated Utrecht Work Engagement Scale questionnaire.Results:Overall,WE levels were average,with similar trends across the three subdomains.In the bootstrapped multivariate linear regression model,anxiety was negatively associated with WE(β=-0.49,95%confidence interval[CI]:-0.77 to-0.21).Conversely,working in an urban area(β=0.36,95%CI:0.05 to 0.67),holding the rank of PA/Senior PA(β=0.27,95%CI:0.03 to 0.52),reporting good self-rated health(β=0.54,95%CI:0.19 to 0.88),and working at health centers(β=0.86,95%CI:0.22 to 1.50)were positively associated with WElevels.Conclusion:WE levels are average in the study sample,highlighting the need for strategic interventions to improve and sustain the healthcare workforce's motivation and performance.Addressing workplace stressors,enhancing professional development opportunities,and fostering supportive work environments could improve engagement among PAs and healthcare professionals in general.Strengthening WE is essential for ensuring resilient quality primary healthcare systems and achieving the goals of universal health coverage.
文摘Intelligent personal assistants play a pivotal role in in-vehicle systems,significantly enhancing life efficiency,driving safety,and decision-making support.In this study,the multi-modal design elements of intelligent personal assistants within the context of visual,auditory,and somatosensory interactions with drivers were discussed.Their impact on the driver’s psychological state through various modes such as visual imagery,voice interaction,and gesture interaction were explored.The study also introduced innovative designs for in-vehicle intelligent personal assistants,incorporating design principles such as driver-centricity,prioritizing passenger safety,and utilizing timely feedback as a criterion.Additionally,the study employed design methods like driver behavior research and driving situation analysis to enhance the emotional connection between drivers and their vehicles,ultimately improving driver satisfaction and trust.
文摘This article examines the implementation of a virtual health assistant powered by Retrieval-Augmented Generation (RAG) and GPT-4, aimed at enhancing clinical support through personalized, real-time interactions with patients. The system is hypothesized to improve healthcare accessibility, operational efficiency, and patient outcomes by automating routine tasks and delivering accurate health information. The assistant leverages natural language processing and real-time data retrieval models to respond to patient inquiries, schedule appointments, provide medication reminders, assist with symptom triage, and answer insurance-related questions. By integrating RAG-based virtual care, the system reduces the burden on healthcare specialists and helps mitigate healthcare disparities, particularly in rural areas where traditional care is limited. Although the initial scope of testing did not validate all potential benefits, the results demonstrated high patient satisfaction and strong response accuracy, both critical for systems of this nature. These findings underscore the transformative potential of AI-driven virtual health assistants in enhancing patient engagement, streamlining operational workflows, and improving healthcare accessibility, ultimately contributing to better outcomes and more cost-effective care delivery.
基金Project(A11024)supported by the Key Laboratory Fund of Geo-Informatics of State Bureau of Surveying and MappingProject(7771022)supported by the Basic Research Fund for Chinese Academy of Surveying and MappingProject(2010AA22202)supported by the National High-tech Research and Development Program of China
文摘Conceptual design, data model and key techniques of "Geo-engineer 3D assistant", an underground 3D GIS oriented to geology and mine application, were discussed. In particular, the importance of high-order smoothing triangular pieces to surface's fine expression in geological modeling was emphasized. The contour mode is the most favorite mode of the three modes about surface expression: DEM, TIN and contour. Topology in underground 3D modeling with CAGD was compared. From the view of boundary and coboundary, which is soul of IS 19107 (Geographic information spatial schema), 3D underground topology was re-examined.
基金Funded by the Special Fund of Basic Scientific Research of Rubber Research Institute of CATASKey Laboratory of Ministry of Agriculture for Natural Rubber Processing (No. xjszx-13 and No. xjsbywfzx2009-19, 706057)
文摘Nano SiO2/NR composites were prepared through blending nano SiO2 emulsion with natural rubber latex and then concreting with acetic acid. The emulsion nano SiO2 was prepared with Na2SiO3-9H2O and hydrochloric acid under the reaction of the assistant agents. The was analyzed effect of the application rates of assistant agents such as silane coupling agent, surfactant, nucleating agent and dispersant on the properties and interface structure of the nano SiO2/NR composites with IR, TEM, SEM, DMA was analyzed. An orthogonal test was arranged to select optimum condition. The results show that the best combination for preparing nano SiO2/NR composites is as follows： the rate of the silane coupling agent （TESPT）, the surfactant（dodecyl benzene sulfonate natrium）, nucleating agent（AlCl3） and dispersant（ethylene diamine tetraacetie acid） in the course of preparing nano SiO2 are 15%, 2.0%, 2.5% and 0.4%, respectively. Several replications in the experiment had produced desirable nano SiO2 products and nano SiO2/NR composites with better properties.
文摘The laparoendoscopic single-site （LESS） technique is the latest technical innovation in laparoscopic surgery to undergo exponential development in urology. This study undertaken to illustrate our initial experience LESS radical prostatectomy （RP） and analyze early outcomes. Nineteen patients diagnosed with prostate cancer underwent LESS-RP in our institute. The patients were divided into two groups： conventional LESS and transurethral assistant LESS. Preoperative, perioperative, postoperative, pathologic, and functional outcomes data were assessed. With the help of a transurethral assistant, the mean operation and anastomosis time were decreased markedly. No focal positive margins were encountered. No prostate-specific antigen recurrence was detected 1 month postoperatively. Complete continence recovery （no pad） was observed in 32% of the patients at 1 month after the operation. No intraoperative and postoperative complications were reported, LESS-RP is a feasible and effective surgical procedure for treatment of prostate cancer. Moreover, transurethral assistant LESS could reduce the difficulty of LESS-RP and shorten the operation time.
基金supported by the National Natural Science Foundation of China(21633009,21925206,21902156)the Dalian National Laboratory for Clean Energy(DNL)Cooperation Fund,CAS(no.DNL 201913)+2 种基金the International Partnership Program of Chinese Academy of Sciences(121421KYSB20190025)the DICP foundation of innovative research(DICP I201927)the support from Liao Ning Revitalization Talents Program(XLYC1807241)。
文摘Cocatalysts play a vital role in accelerating the reaction kinetics and improving the charge separation of photocatalysts for solar hydrogen production.The promotion of the photocatalytic activity largely relies on the loading approach of the cocatalysts.Herein,we introduce a metal-seed assistant photodeposition approach to load the hydrogen evolution cocatalyst of platinum onto the surface of Ta_(3)N_(5) photocatalyst,which exhibits about 3.6 times of higher photocatalytic proton reduction activity with respect to the corresponding impregnation or photodeposition loading.Based on our characterizations,the increscent contact area of the cocatalyst/semiconductor interface with metal-seed assistant photodeposition method is proposed to be responsible for the promoted charge separation as well as enhanced photocatalytic H2 evolution activity.It is interesting to note that this innovative deposition strategy can be easily extended to loading of platinum cocatalyst with other noble or non-noble metal seeds for promoted activities,demonstrating its good generality.Our work may provide an alternative way of depositing cocatalyst for better photocatalytic performances.
基金Funding National Natural Science Foundation of China(51709061,51779057).
文摘Stealth security has always been considered as an important guarantee for the vitality and combat effectiveness of submarines.In accordance with the stealth requirements of submarines performing stealth voyage tasks,this paper proposes a stealth assistant decision system.Firstly,the submarine stealth posture is acquired.A fuzzy neural network inference engine based on improved simplified particle swarm optimization is designed.The auxiliary decision-making scheme for state control and maneuver avoidance of submarine and its equipment is automatically generated.Secondly,the simulation and deduction of the assistant decision-making scheme are realized by the calculation modules of sound source level,propagation loss,and stealth situation.The assistant decision-making scheme and simulation result provide decision support for the commander.Thirdly,the simulation experiment platform of the submarine stealth assistant decision system is constructed.The submarine stealth assistant decision system described in this paper can quickly and efficiently produce assistant decision-making schemes,including submarine and equipment control and maneuver avoidance.The scheme is in line with the combat experience and the results of the pre-model simulation experiments,whereas the simulation deduction evaluates the rationality and effectiveness of the selected scheme.The submarine stealth assistant decision system can adapt to a complex battlefield environment in addition to rapidly and accurately providing assistance in decision-making.
基金National Science and Technology Support Program of China(No.2006BAG04B03)
文摘Sutong Bridge is a cable-stayed steel box girder bridge with a main span of 1 088 m. The erection of upper structure adopts geometry control method and requires no change to the unit＇ s size and the structure＇ s none-stress geometry. Before main span closure, the cantilever of girder reaches 540.8 m, the structure state is noticeably influenced by extemal circumstances, the main span closure face great difficulty. By abstracting the advantage of the pullback method abroad and the domestic temperature-cutting method, a new assistant pullback method have put forward and bring into practice actually. In this paper, the analysis key point of practice conditions, key parameter of practice, main measures of the method and the performance is introduced.
基金Supported by the National Natural Science Foundation of China(21176014,20990221,21121064)the Science-Technology Project for Supervisors of Excellent Doctor Degree Thesis of Beijing(20111001001)
文摘A slow bromination process of butyl rubber （IIR） suffers from low efficiency and low selectivity （S） of target-product. To obtain suitable approach to intensify the process, effects of assistant solvents and mixing inten-sity on the bromination process were systemically studied in this paper. The reaction process was found constantly accelerated with the increasing dosage and polarity of assistant solvent. Hexane with 30%（by volume） dichloro-methane was found as the suitable solvent component, where the stable conversion of 1,4-isoprene transferring to target product （xA1s） of 80.2%and the corresponding S of 91.2%were obtained in 5 min. The accelerated reaction process was demonstrated being remarkably affected by mixing intensity until the optimal stirring rate of 1100 r＆#183;min-1 in a stirred tank reactor. With better mixing condition, a further intensification of the process was achieved in a ro-tating packed bed （RPB） reactor, where xA1s of 82.6% and S of 91.9% were obtained in 2 min. The usage of the suitable solvent component and RPB has potential application in the industrial bromination process intensification.
文摘The first mid-term election of the U. S. in the new century took place on November 5, 2002. One third of the senators from the 107th Congress (34 out of 100), all representatives (435), 36 state governors, and numerous local officials and legislators were to be elected or reelected. The resounding victory of the GOP in the congressional elections and the fact that the Democrats only got three more.
